bpf.h source code [Linux/include/uapi/linux/bpf.h]

1	/ SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note /
2	/ Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com*
3	*
4	* This program is free software; you can redistribute it and/or
5	* modify it under the terms of version 2 of the GNU General Public
6	* License as published by the Free Software Foundation.
7	*/
8	#ifndef _UAPI__LINUX_BPF_H__
9	#define _UAPI__LINUX_BPF_H__
10
11	#include <linux/types.h>
12	#include <linux/bpf_common.h>
13
14	/ Extended instruction set based on top of classic BPF /
15
16	/ instruction classes /
17	#define BPF_JMP32 0x06 /* jmp mode in word width */
18	#define BPF_ALU64 0x07 /* alu mode in double word width */
19
20	/ ld/ldx fields /
21	#define BPF_DW 0x18 /* double word (64-bit) */
22	#define BPF_MEMSX 0x80 /* load with sign extension */
23	#define BPF_ATOMIC 0xc0 /* atomic memory ops - op type in immediate */
24	#define BPF_XADD 0xc0 /* exclusive add - legacy name */
25
26	/ alu/jmp fields /
27	#define BPF_MOV 0xb0 /* mov reg to reg */
28	#define BPF_ARSH 0xc0 /* sign extending arithmetic shift right */
29
30	/ change endianness of a register /
31	#define BPF_END 0xd0 /* flags for endianness conversion: */
32	#define BPF_TO_LE 0x00 /* convert to little-endian */
33	#define BPF_TO_BE 0x08 /* convert to big-endian */
34	#define BPF_FROM_LE BPF_TO_LE
35	#define BPF_FROM_BE BPF_TO_BE
36
37	/ jmp encodings /
38	#define BPF_JNE 0x50 /* jump != */
39	#define BPF_JLT 0xa0 /* LT is unsigned, '<' */
40	#define BPF_JLE 0xb0 /* LE is unsigned, '<=' */
41	#define BPF_JSGT 0x60 /* SGT is signed '>', GT in x86 */
42	#define BPF_JSGE 0x70 /* SGE is signed '>=', GE in x86 */
43	#define BPF_JSLT 0xc0 /* SLT is signed, '<' */
44	#define BPF_JSLE 0xd0 /* SLE is signed, '<=' */
45	#define BPF_JCOND 0xe0 /* conditional pseudo jumps: may_goto, goto_or_nop */
46	#define BPF_CALL 0x80 /* function call */
47	#define BPF_EXIT 0x90 /* function return */
48
49	/ atomic op type fields (stored in immediate) /
50	#define BPF_FETCH 0x01 /* not an opcode on its own, used to build others */
51	#define BPF_XCHG (0xe0 \| BPF_FETCH) /* atomic exchange */
52	#define BPF_CMPXCHG (0xf0 \| BPF_FETCH) /* atomic compare-and-write */
53
54	#define BPF_LOAD_ACQ 0x100 /* load-acquire */
55	#define BPF_STORE_REL 0x110 /* store-release */
56
57	enum bpf_cond_pseudo_jmp {
58	BPF_MAY_GOTO = `0`,
59	};
60
61	/ Register numbers /
62	enum {
63	BPF_REG_0 = `0`,
64	BPF_REG_1,
65	BPF_REG_2,
66	BPF_REG_3,
67	BPF_REG_4,
68	BPF_REG_5,
69	BPF_REG_6,
70	BPF_REG_7,
71	BPF_REG_8,
72	BPF_REG_9,
73	BPF_REG_10,
74	__MAX_BPF_REG,
75	};
76
77	/ BPF has 10 general purpose 64-bit registers and stack frame. /
78	#define MAX_BPF_REG __MAX_BPF_REG
79
80	struct bpf_insn {
81	__u8 code; / opcode /
82	__u8 dst_reg:`4`; / dest register /
83	__u8 src_reg:`4`; / source register /
84	__s16 off; / signed offset /
85	__s32 imm; / signed immediate constant /
86	};
87
88	/ Deprecated: use struct bpf_lpm_trie_key_u8 (when the "data" member is needed for*
89	* byte access) or struct bpf_lpm_trie_key_hdr (when using an alternative type for
90	* the trailing flexible array member) instead.
91	*/
92	struct bpf_lpm_trie_key {
93	__u32 prefixlen; / up to 32 for AF_INET, 128 for AF_INET6 /
94	__u8 data[`0`]; / Arbitrary size /
95	};
96
97	/ Header for bpf_lpm_trie_key structs /
98	struct bpf_lpm_trie_key_hdr {
99	__u32 prefixlen;
100	};
101
102	/ Key of an a BPF_MAP_TYPE_LPM_TRIE entry, with trailing byte array. /
103	struct bpf_lpm_trie_key_u8 {
104	union {
105	struct bpf_lpm_trie_key_hdr hdr;
106	__u32 prefixlen;
107	};
108	__u8 data[]; / Arbitrary size /
109	};
110
111	struct bpf_cgroup_storage_key {
112	__u64 cgroup_inode_id; / cgroup inode id /
113	__u32 attach_type; / program attach type (enum bpf_attach_type) /
114	};
115
116	enum bpf_cgroup_iter_order {
117	BPF_CGROUP_ITER_ORDER_UNSPEC = `0`,
118	BPF_CGROUP_ITER_SELF_ONLY, / process only a single object. /
119	BPF_CGROUP_ITER_DESCENDANTS_PRE, / walk descendants in pre-order. /
120	BPF_CGROUP_ITER_DESCENDANTS_POST, / walk descendants in post-order. /
121	BPF_CGROUP_ITER_ANCESTORS_UP, / walk ancestors upward. /
122	};
123
124	union bpf_iter_link_info {
125	struct {
126	__u32 map_fd;
127	} map;
128	struct {
129	enum bpf_cgroup_iter_order order;
130
131	/ At most one of cgroup_fd and cgroup_id can be non-zero. If*
132	* both are zero, the walk starts from the default cgroup v2
133	* root. For walking v1 hierarchy, one should always explicitly
134	* specify cgroup_fd.
135	*/
136	__u32 cgroup_fd;
137	__u64 cgroup_id;
138	} cgroup;
139	/ Parameters of task iterators. /
140	struct {
141	__u32 tid;
142	__u32 pid;
143	__u32 pid_fd;
144	} task;
145	};
146
147	/ BPF syscall commands, see bpf(2) man-page for more details. /
148	/**
149	* DOC: eBPF Syscall Preamble
150	*
151	* The operation to be performed by the bpf\ () system call is determined
152	* by the cmd argument. Each operation takes an accompanying argument,
153	* provided via attr, which is a pointer to a union of type bpf_attr (see
154	* below). The size argument is the size of the union pointed to by attr.
155	*/
156	/**
157	* DOC: eBPF Syscall Commands
158	*
159	* BPF_MAP_CREATE
160	* Description
161	* Create a map and return a file descriptor that refers to the
162	* map. The close-on-exec file descriptor flag (see fcntl\ (2))
163	* is automatically enabled for the new file descriptor.
164	*
165	* Applying close\ (2) to the file descriptor returned by
166	* BPF_MAP_CREATE will delete the map (but see NOTES).
167	*
168	* Return
169	* A new file descriptor (a nonnegative integer), or -1 if an
170	* error occurred (in which case, errno is set appropriately).
171	*
172	* BPF_MAP_LOOKUP_ELEM
173	* Description
174	* Look up an element with a given key in the map referred to
175	* by the file descriptor map_fd.
176	*
177	* The flags argument may be specified as one of the
178	* following:
179	*
180	* BPF_F_LOCK
181	* Look up the value of a spin-locked map without
182	* returning the lock. This must be specified if the
183	* elements contain a spinlock.
184	*
185	* Return
186	* Returns zero on success. On error, -1 is returned and errno
187	* is set appropriately.
188	*
189	* BPF_MAP_UPDATE_ELEM
190	* Description
191	* Create or update an element (key/value pair) in a specified map.
192	*
193	* The flags argument should be specified as one of the
194	* following:
195	*
196	* BPF_ANY
197	* Create a new element or update an existing element.
198	* BPF_NOEXIST
199	* Create a new element only if it did not exist.
200	* BPF_EXIST
201	* Update an existing element.
202	* BPF_F_LOCK
203	* Update a spin_lock-ed map element.
204	*
205	* Return
206	* Returns zero on success. On error, -1 is returned and errno
207	* is set appropriately.
208	*
209	* May set errno to EINVAL, EPERM, ENOMEM,
210	* E2BIG, EEXIST, or ENOENT.
211	*
212	* E2BIG
213	* The number of elements in the map reached the
214	* max_entries limit specified at map creation time.
215	* EEXIST
216	* If flags specifies BPF_NOEXIST and the element
217	* with key already exists in the map.
218	* ENOENT
219	* If flags specifies BPF_EXIST and the element with
220	* key does not exist in the map.
221	*
222	* BPF_MAP_DELETE_ELEM
223	* Description
224	* Look up and delete an element by key in a specified map.
225	*
226	* Return
227	* Returns zero on success. On error, -1 is returned and errno
228	* is set appropriately.
229	*
230	* BPF_MAP_GET_NEXT_KEY
231	* Description
232	* Look up an element by key in a specified map and return the key
233	* of the next element. Can be used to iterate over all elements
234	* in the map.
235	*
236	* Return
237	* Returns zero on success. On error, -1 is returned and errno
238	* is set appropriately.
239	*
240	* The following cases can be used to iterate over all elements of
241	* the map:
242	*
243	* * If key is not found, the operation returns zero and sets
244	* the next_key pointer to the key of the first element.
245	* * If key is found, the operation returns zero and sets the
246	* next_key pointer to the key of the next element.
247	* * If key is the last element, returns -1 and errno is set
248	* to ENOENT.
249	*
250	* May set errno to ENOMEM, EFAULT, EPERM, or
251	* EINVAL on error.
252	*
253	* BPF_PROG_LOAD
254	* Description
255	* Verify and load an eBPF program, returning a new file
256	* descriptor associated with the program.
257	*
258	* Applying close\ (2) to the file descriptor returned by
259	* BPF_PROG_LOAD will unload the eBPF program (but see NOTES).
260	*
261	* The close-on-exec file descriptor flag (see fcntl\ (2)) is
262	* automatically enabled for the new file descriptor.
263	*
264	* Return
265	* A new file descriptor (a nonnegative integer), or -1 if an
266	* error occurred (in which case, errno is set appropriately).
267	*
268	* BPF_OBJ_PIN
269	* Description
270	* Pin an eBPF program or map referred by the specified bpf_fd
271	* to the provided pathname on the filesystem.
272	*
273	* The pathname argument must not contain a dot (".").
274	*
275	* On success, pathname retains a reference to the eBPF object,
276	* preventing deallocation of the object when the original
277	* bpf_fd is closed. This allow the eBPF object to live beyond
278	* close\ (\ bpf_fd\ ), and hence the lifetime of the parent
279	* process.
280	*
281	* Applying unlink\ (2) or similar calls to the pathname
282	* unpins the object from the filesystem, removing the reference.
283	* If no other file descriptors or filesystem nodes refer to the
284	* same object, it will be deallocated (see NOTES).
285	*
286	* The filesystem type for the parent directory of pathname must
287	* be BPF_FS_MAGIC.
288	*
289	* Return
290	* Returns zero on success. On error, -1 is returned and errno
291	* is set appropriately.
292	*
293	* BPF_OBJ_GET
294	* Description
295	* Open a file descriptor for the eBPF object pinned to the
296	* specified pathname.
297	*
298	* Return
299	* A new file descriptor (a nonnegative integer), or -1 if an
300	* error occurred (in which case, errno is set appropriately).
301	*
302	* BPF_PROG_ATTACH
303	* Description
304	* Attach an eBPF program to a target_fd at the specified
305	* attach_type hook.
306	*
307	* The attach_type specifies the eBPF attachment point to
308	* attach the program to, and must be one of bpf_attach_type
309	* (see below).
310	*
311	* The attach_bpf_fd must be a valid file descriptor for a
312	* loaded eBPF program of a cgroup, flow dissector, LIRC, sockmap
313	* or sock_ops type corresponding to the specified attach_type.
314	*
315	* The target_fd must be a valid file descriptor for a kernel
316	* object which depends on the attach type of attach_bpf_fd:
317	*
318	* BPF_PROG_TYPE_CGROUP_DEVICE,
319	* BPF_PROG_TYPE_CGROUP_SKB,
320	* BPF_PROG_TYPE_CGROUP_SOCK,
321	* BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
322	* BPF_PROG_TYPE_CGROUP_SOCKOPT,
323	* BPF_PROG_TYPE_CGROUP_SYSCTL,
324	* BPF_PROG_TYPE_SOCK_OPS
325	*
326	* Control Group v2 hierarchy with the eBPF controller
327	* enabled. Requires the kernel to be compiled with
328	* CONFIG_CGROUP_BPF.
329	*
330	* BPF_PROG_TYPE_FLOW_DISSECTOR
331	*
332	* Network namespace (eg /proc/self/ns/net).
333	*
334	* BPF_PROG_TYPE_LIRC_MODE2
335	*
336	* LIRC device path (eg /dev/lircN). Requires the kernel
337	* to be compiled with CONFIG_BPF_LIRC_MODE2.
338	*
339	* BPF_PROG_TYPE_SK_SKB,
340	* BPF_PROG_TYPE_SK_MSG
341	*
342	* eBPF map of socket type (eg BPF_MAP_TYPE_SOCKHASH).
343	*
344	* Return
345	* Returns zero on success. On error, -1 is returned and errno
346	* is set appropriately.
347	*
348	* BPF_PROG_DETACH
349	* Description
350	* Detach the eBPF program associated with the target_fd at the
351	* hook specified by attach_type. The program must have been
352	* previously attached using BPF_PROG_ATTACH.
353	*
354	* Return
355	* Returns zero on success. On error, -1 is returned and errno
356	* is set appropriately.
357	*
358	* BPF_PROG_TEST_RUN
359	* Description
360	* Run the eBPF program associated with the prog_fd a repeat
361	* number of times against a provided program context ctx_in and
362	* data data_in, and return the modified program context
363	* ctx_out, data_out (for example, packet data), result of the
364	* execution retval, and duration of the test run.
365	*
366	* The sizes of the buffers provided as input and output
367	* parameters ctx_in, ctx_out, data_in, and data_out must
368	* be provided in the corresponding variables ctx_size_in,
369	* ctx_size_out, data_size_in, and/or data_size_out. If any
370	* of these parameters are not provided (ie set to NULL), the
371	* corresponding size field must be zero.
372	*
373	* Some program types have particular requirements:
374	*
375	* BPF_PROG_TYPE_SK_LOOKUP
376	* data_in and data_out must be NULL.
377	*
378	* BPF_PROG_TYPE_RAW_TRACEPOINT,
379	* BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE
380	*
381	* ctx_out, data_in and data_out must be NULL.
382	* repeat must be zero.
383	*
384	* BPF_PROG_RUN is an alias for BPF_PROG_TEST_RUN.
385	*
386	* Return
387	* Returns zero on success. On error, -1 is returned and errno
388	* is set appropriately.
389	*
390	* ENOSPC
391	* Either data_size_out or ctx_size_out is too small.
392	* ENOTSUPP
393	* This command is not supported by the program type of
394	* the program referred to by prog_fd.
395	*
396	* BPF_PROG_GET_NEXT_ID
397	* Description
398	* Fetch the next eBPF program currently loaded into the kernel.
399	*
400	* Looks for the eBPF program with an id greater than start_id
401	* and updates next_id on success. If no other eBPF programs
402	* remain with ids higher than start_id, returns -1 and sets
403	* errno to ENOENT.
404	*
405	* Return
406	* Returns zero on success. On error, or when no id remains, -1
407	* is returned and errno is set appropriately.
408	*
409	* BPF_MAP_GET_NEXT_ID
410	* Description
411	* Fetch the next eBPF map currently loaded into the kernel.
412	*
413	* Looks for the eBPF map with an id greater than start_id
414	* and updates next_id on success. If no other eBPF maps
415	* remain with ids higher than start_id, returns -1 and sets
416	* errno to ENOENT.
417	*
418	* Return
419	* Returns zero on success. On error, or when no id remains, -1
420	* is returned and errno is set appropriately.
421	*
422	* BPF_PROG_GET_FD_BY_ID
423	* Description
424	* Open a file descriptor for the eBPF program corresponding to
425	* prog_id.
426	*
427	* Return
428	* A new file descriptor (a nonnegative integer), or -1 if an
429	* error occurred (in which case, errno is set appropriately).
430	*
431	* BPF_MAP_GET_FD_BY_ID
432	* Description
433	* Open a file descriptor for the eBPF map corresponding to
434	* map_id.
435	*
436	* Return
437	* A new file descriptor (a nonnegative integer), or -1 if an
438	* error occurred (in which case, errno is set appropriately).
439	*
440	* BPF_OBJ_GET_INFO_BY_FD
441	* Description
442	* Obtain information about the eBPF object corresponding to
443	* bpf_fd.
444	*
445	* Populates up to info_len bytes of info, which will be in
446	* one of the following formats depending on the eBPF object type
447	* of bpf_fd:
448	*
449	* * struct bpf_prog_info
450	* * struct bpf_map_info
451	* * struct bpf_btf_info
452	* * struct bpf_link_info
453	* * struct bpf_token_info
454	*
455	* Return
456	* Returns zero on success. On error, -1 is returned and errno
457	* is set appropriately.
458	*
459	* BPF_PROG_QUERY
460	* Description
461	* Obtain information about eBPF programs associated with the
462	* specified attach_type hook.
463	*
464	* The target_fd must be a valid file descriptor for a kernel
465	* object which depends on the attach type of attach_bpf_fd:
466	*
467	* BPF_PROG_TYPE_CGROUP_DEVICE,
468	* BPF_PROG_TYPE_CGROUP_SKB,
469	* BPF_PROG_TYPE_CGROUP_SOCK,
470	* BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
471	* BPF_PROG_TYPE_CGROUP_SOCKOPT,
472	* BPF_PROG_TYPE_CGROUP_SYSCTL,
473	* BPF_PROG_TYPE_SOCK_OPS
474	*
475	* Control Group v2 hierarchy with the eBPF controller
476	* enabled. Requires the kernel to be compiled with
477	* CONFIG_CGROUP_BPF.
478	*
479	* BPF_PROG_TYPE_FLOW_DISSECTOR
480	*
481	* Network namespace (eg /proc/self/ns/net).
482	*
483	* BPF_PROG_TYPE_LIRC_MODE2
484	*
485	* LIRC device path (eg /dev/lircN). Requires the kernel
486	* to be compiled with CONFIG_BPF_LIRC_MODE2.
487	*
488	* BPF_PROG_QUERY always fetches the number of programs
489	* attached and the attach_flags which were used to attach those
490	* programs. Additionally, if prog_ids is nonzero and the number
491	* of attached programs is less than prog_cnt, populates
492	* prog_ids with the eBPF program ids of the programs attached
493	* at target_fd.
494	*
495	* The following flags may alter the result:
496	*
497	* BPF_F_QUERY_EFFECTIVE
498	* Only return information regarding programs which are
499	* currently effective at the specified target_fd.
500	*
501	* Return
502	* Returns zero on success. On error, -1 is returned and errno
503	* is set appropriately.
504	*
505	* BPF_RAW_TRACEPOINT_OPEN
506	* Description
507	* Attach an eBPF program to a tracepoint name to access kernel
508	* internal arguments of the tracepoint in their raw form.
509	*
510	* The prog_fd must be a valid file descriptor associated with
511	* a loaded eBPF program of type BPF_PROG_TYPE_RAW_TRACEPOINT.
512	*
513	* No ABI guarantees are made about the content of tracepoint
514	* arguments exposed to the corresponding eBPF program.
515	*
516	* Applying close\ (2) to the file descriptor returned by
517	* BPF_RAW_TRACEPOINT_OPEN will delete the map (but see NOTES).
518	*
519	* Return
520	* A new file descriptor (a nonnegative integer), or -1 if an
521	* error occurred (in which case, errno is set appropriately).
522	*
523	* BPF_BTF_LOAD
524	* Description
525	* Verify and load BPF Type Format (BTF) metadata into the kernel,
526	* returning a new file descriptor associated with the metadata.
527	* BTF is described in more detail at
528	* https://www.kernel.org/doc/html/latest/bpf/btf.html.
529	*
530	* The btf parameter must point to valid memory providing
531	* btf_size bytes of BTF binary metadata.
532	*
533	* The returned file descriptor can be passed to other bpf\ ()
534	* subcommands such as BPF_PROG_LOAD or BPF_MAP_CREATE to
535	* associate the BTF with those objects.
536	*
537	* Similar to BPF_PROG_LOAD, BPF_BTF_LOAD has optional
538	* parameters to specify a btf_log_buf, btf_log_size and
539	* btf_log_level which allow the kernel to return freeform log
540	* output regarding the BTF verification process.
541	*
542	* Return
543	* A new file descriptor (a nonnegative integer), or -1 if an
544	* error occurred (in which case, errno is set appropriately).
545	*
546	* BPF_BTF_GET_FD_BY_ID
547	* Description
548	* Open a file descriptor for the BPF Type Format (BTF)
549	* corresponding to btf_id.
550	*
551	* Return
552	* A new file descriptor (a nonnegative integer), or -1 if an
553	* error occurred (in which case, errno is set appropriately).
554	*
555	* BPF_TASK_FD_QUERY
556	* Description
557	* Obtain information about eBPF programs associated with the
558	* target process identified by pid and fd.
559	*
560	* If the pid and fd are associated with a tracepoint, kprobe
561	* or uprobe perf event, then the prog_id and fd_type will
562	* be populated with the eBPF program id and file descriptor type
563	* of type bpf_task_fd_type. If associated with a kprobe or
564	* uprobe, the probe_offset and probe_addr will also be
565	* populated. Optionally, if buf is provided, then up to
566	* buf_len bytes of buf will be populated with the name of
567	* the tracepoint, kprobe or uprobe.
568	*
569	* The resulting prog_id may be introspected in deeper detail
570	* using BPF_PROG_GET_FD_BY_ID and BPF_OBJ_GET_INFO_BY_FD.
571	*
572	* Return
573	* Returns zero on success. On error, -1 is returned and errno
574	* is set appropriately.
575	*
576	* BPF_MAP_LOOKUP_AND_DELETE_ELEM
577	* Description
578	* Look up an element with the given key in the map referred to
579	* by the file descriptor fd, and if found, delete the element.
580	*
581	* For BPF_MAP_TYPE_QUEUE and BPF_MAP_TYPE_STACK map
582	* types, the flags argument needs to be set to 0, but for other
583	* map types, it may be specified as:
584	*
585	* BPF_F_LOCK
586	* Look up and delete the value of a spin-locked map
587	* without returning the lock. This must be specified if
588	* the elements contain a spinlock.
589	*
590	* The BPF_MAP_TYPE_QUEUE and BPF_MAP_TYPE_STACK map types
591	* implement this command as a "pop" operation, deleting the top
592	* element rather than one corresponding to key.
593	* The key and key_len parameters should be zeroed when
594	* issuing this operation for these map types.
595	*
596	* This command is only valid for the following map types:
597	* * BPF_MAP_TYPE_QUEUE
598	* * BPF_MAP_TYPE_STACK
599	* * BPF_MAP_TYPE_HASH
600	* * BPF_MAP_TYPE_PERCPU_HASH
601	* * BPF_MAP_TYPE_LRU_HASH
602	* * BPF_MAP_TYPE_LRU_PERCPU_HASH
603	*
604	* Return
605	* Returns zero on success. On error, -1 is returned and errno
606	* is set appropriately.
607	*
608	* BPF_MAP_FREEZE
609	* Description
610	* Freeze the permissions of the specified map.
611	*
612	* Write permissions may be frozen by passing zero flags.
613	* Upon success, no future syscall invocations may alter the
614	* map state of map_fd. Write operations from eBPF programs
615	* are still possible for a frozen map.
616	*
617	* Not supported for maps of type BPF_MAP_TYPE_STRUCT_OPS.
618	*
619	* Return
620	* Returns zero on success. On error, -1 is returned and errno
621	* is set appropriately.
622	*
623	* BPF_BTF_GET_NEXT_ID
624	* Description
625	* Fetch the next BPF Type Format (BTF) object currently loaded
626	* into the kernel.
627	*
628	* Looks for the BTF object with an id greater than start_id
629	* and updates next_id on success. If no other BTF objects
630	* remain with ids higher than start_id, returns -1 and sets
631	* errno to ENOENT.
632	*
633	* Return
634	* Returns zero on success. On error, or when no id remains, -1
635	* is returned and errno is set appropriately.
636	*
637	* BPF_MAP_LOOKUP_BATCH
638	* Description
639	* Iterate and fetch multiple elements in a map.
640	*
641	* Two opaque values are used to manage batch operations,
642	* in_batch and out_batch. Initially, in_batch must be set
643	* to NULL to begin the batched operation. After each subsequent
644	* BPF_MAP_LOOKUP_BATCH, the caller should pass the resultant
645	* out_batch as the in_batch for the next operation to
646	* continue iteration from the current point. Both in_batch and
647	* out_batch must point to memory large enough to hold a key,
648	* except for maps of type **BPF_MAP_TYPE_{HASH, PERCPU_HASH,
649	* LRU_HASH, LRU_PERCPU_HASH}**, for which batch parameters
650	* must be at least 4 bytes wide regardless of key size.
651	*
652	* The keys and values are output parameters which must point
653	* to memory large enough to hold count items based on the key
654	* and value size of the map map_fd. The keys buffer must be
655	* of key_size * count. The values buffer must be of
656	* value_size * count.
657	*
658	* The elem_flags argument may be specified as one of the
659	* following:
660	*
661	* BPF_F_LOCK
662	* Look up the value of a spin-locked map without
663	* returning the lock. This must be specified if the
664	* elements contain a spinlock.
665	*
666	* On success, count elements from the map are copied into the
667	* user buffer, with the keys copied into keys and the values
668	* copied into the corresponding indices in values.
669	*
670	* If an error is returned and errno is not EFAULT, count
671	* is set to the number of successfully processed elements.
672	*
673	* Return
674	* Returns zero on success. On error, -1 is returned and errno
675	* is set appropriately.
676	*
677	* May set errno to ENOSPC to indicate that keys or
678	* values is too small to dump an entire bucket during
679	* iteration of a hash-based map type.
680	*
681	* BPF_MAP_LOOKUP_AND_DELETE_BATCH
682	* Description
683	* Iterate and delete all elements in a map.
684	*
685	* This operation has the same behavior as
686	* BPF_MAP_LOOKUP_BATCH with two exceptions:
687	*
688	* * Every element that is successfully returned is also deleted
689	* from the map. This is at least count elements. Note that
690	* count is both an input and an output parameter.
691	* * Upon returning with errno set to EFAULT, up to
692	* count elements may be deleted without returning the keys
693	* and values of the deleted elements.
694	*
695	* Return
696	* Returns zero on success. On error, -1 is returned and errno
697	* is set appropriately.
698	*
699	* BPF_MAP_UPDATE_BATCH
700	* Description
701	* Update multiple elements in a map by key.
702	*
703	* The keys and values are input parameters which must point
704	* to memory large enough to hold count items based on the key
705	* and value size of the map map_fd. The keys buffer must be
706	* of key_size * count. The values buffer must be of
707	* value_size * count.
708	*
709	* Each element specified in keys is sequentially updated to the
710	* value in the corresponding index in values. The in_batch
711	* and out_batch parameters are ignored and should be zeroed.
712	*
713	* The elem_flags argument should be specified as one of the
714	* following:
715	*
716	* BPF_ANY
717	* Create new elements or update a existing elements.
718	* BPF_NOEXIST
719	* Create new elements only if they do not exist.
720	* BPF_EXIST
721	* Update existing elements.
722	* BPF_F_LOCK
723	* Update spin_lock-ed map elements. This must be
724	* specified if the map value contains a spinlock.
725	*
726	* On success, count elements from the map are updated.
727	*
728	* If an error is returned and errno is not EFAULT, count
729	* is set to the number of successfully processed elements.
730	*
731	* Return
732	* Returns zero on success. On error, -1 is returned and errno
733	* is set appropriately.
734	*
735	* May set errno to EINVAL, EPERM, ENOMEM, or
736	* E2BIG. E2BIG indicates that the number of elements in
737	* the map reached the max_entries limit specified at map
738	* creation time.
739	*
740	* May set errno to one of the following error codes under
741	* specific circumstances:
742	*
743	* EEXIST
744	* If flags specifies BPF_NOEXIST and the element
745	* with key already exists in the map.
746	* ENOENT
747	* If flags specifies BPF_EXIST and the element with
748	* key does not exist in the map.
749	*
750	* BPF_MAP_DELETE_BATCH
751	* Description
752	* Delete multiple elements in a map by key.
753	*
754	* The keys parameter is an input parameter which must point
755	* to memory large enough to hold count items based on the key
756	* size of the map map_fd, that is, key_size * count.
757	*
758	* Each element specified in keys is sequentially deleted. The
759	* in_batch, out_batch, and values parameters are ignored
760	* and should be zeroed.
761	*
762	* The elem_flags argument may be specified as one of the
763	* following:
764	*
765	* BPF_F_LOCK
766	* Look up the value of a spin-locked map without
767	* returning the lock. This must be specified if the
768	* elements contain a spinlock.
769	*
770	* On success, count elements from the map are updated.
771	*
772	* If an error is returned and errno is not EFAULT, count
773	* is set to the number of successfully processed elements. If
774	* errno is EFAULT, up to count elements may be been
775	* deleted.
776	*
777	* Return
778	* Returns zero on success. On error, -1 is returned and errno
779	* is set appropriately.
780	*
781	* BPF_LINK_CREATE
782	* Description
783	* Attach an eBPF program to a target_fd at the specified
784	* attach_type hook and return a file descriptor handle for
785	* managing the link.
786	*
787	* Return
788	* A new file descriptor (a nonnegative integer), or -1 if an
789	* error occurred (in which case, errno is set appropriately).
790	*
791	* BPF_LINK_UPDATE
792	* Description
793	* Update the eBPF program in the specified link_fd to
794	* new_prog_fd.
795	*
796	* Return
797	* Returns zero on success. On error, -1 is returned and errno
798	* is set appropriately.
799	*
800	* BPF_LINK_GET_FD_BY_ID
801	* Description
802	* Open a file descriptor for the eBPF Link corresponding to
803	* link_id.
804	*
805	* Return
806	* A new file descriptor (a nonnegative integer), or -1 if an
807	* error occurred (in which case, errno is set appropriately).
808	*
809	* BPF_LINK_GET_NEXT_ID
810	* Description
811	* Fetch the next eBPF link currently loaded into the kernel.
812	*
813	* Looks for the eBPF link with an id greater than start_id
814	* and updates next_id on success. If no other eBPF links
815	* remain with ids higher than start_id, returns -1 and sets
816	* errno to ENOENT.
817	*
818	* Return
819	* Returns zero on success. On error, or when no id remains, -1
820	* is returned and errno is set appropriately.
821	*
822	* BPF_ENABLE_STATS
823	* Description
824	* Enable eBPF runtime statistics gathering.
825	*
826	* Runtime statistics gathering for the eBPF runtime is disabled
827	* by default to minimize the corresponding performance overhead.
828	* This command enables statistics globally.
829	*
830	* Multiple programs may independently enable statistics.
831	* After gathering the desired statistics, eBPF runtime statistics
832	* may be disabled again by calling close\ (2) for the file
833	* descriptor returned by this function. Statistics will only be
834	* disabled system-wide when all outstanding file descriptors
835	* returned by prior calls for this subcommand are closed.
836	*
837	* Return
838	* A new file descriptor (a nonnegative integer), or -1 if an
839	* error occurred (in which case, errno is set appropriately).
840	*
841	* BPF_ITER_CREATE
842	* Description
843	* Create an iterator on top of the specified link_fd (as
844	* previously created using BPF_LINK_CREATE) and return a
845	* file descriptor that can be used to trigger the iteration.
846	*
847	* If the resulting file descriptor is pinned to the filesystem
848	* using BPF_OBJ_PIN, then subsequent read\ (2) syscalls
849	* for that path will trigger the iterator to read kernel state
850	* using the eBPF program attached to link_fd.
851	*
852	* Return
853	* A new file descriptor (a nonnegative integer), or -1 if an
854	* error occurred (in which case, errno is set appropriately).
855	*
856	* BPF_LINK_DETACH
857	* Description
858	* Forcefully detach the specified link_fd from its
859	* corresponding attachment point.
860	*
861	* Return
862	* Returns zero on success. On error, -1 is returned and errno
863	* is set appropriately.
864	*
865	* BPF_PROG_BIND_MAP
866	* Description
867	* Bind a map to the lifetime of an eBPF program.
868	*
869	* The map identified by map_fd is bound to the program
870	* identified by prog_fd and only released when prog_fd is
871	* released. This may be used in cases where metadata should be
872	* associated with a program which otherwise does not contain any
873	* references to the map (for example, embedded in the eBPF
874	* program instructions).
875	*
876	* Return
877	* Returns zero on success. On error, -1 is returned and errno
878	* is set appropriately.
879	*
880	* BPF_TOKEN_CREATE
881	* Description
882	* Create BPF token with embedded information about what
883	* BPF-related functionality it allows:
884	* - a set of allowed bpf() syscall commands;
885	* - a set of allowed BPF map types to be created with
886	* BPF_MAP_CREATE command, if BPF_MAP_CREATE itself is allowed;
887	* - a set of allowed BPF program types and BPF program attach
888	* types to be loaded with BPF_PROG_LOAD command, if
889	* BPF_PROG_LOAD itself is allowed.
890	*
891	* BPF token is created (derived) from an instance of BPF FS,
892	* assuming it has necessary delegation mount options specified.
893	* This BPF token can be passed as an extra parameter to various
894	* bpf() syscall commands to grant BPF subsystem functionality to
895	* unprivileged processes.
896	*
897	* When created, BPF token is "associated" with the owning
898	* user namespace of BPF FS instance (super block) that it was
899	* derived from, and subsequent BPF operations performed with
900	* BPF token would be performing capabilities checks (i.e.,
901	* CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN) within
902	* that user namespace. Without BPF token, such capabilities
903	* have to be granted in init user namespace, making bpf()
904	* syscall incompatible with user namespace, for the most part.
905	*
906	* Return
907	* A new file descriptor (a nonnegative integer), or -1 if an
908	* error occurred (in which case, errno is set appropriately).
909	*
910	* BPF_PROG_STREAM_READ_BY_FD
911	* Description
912	* Read data of a program's BPF stream. The program is identified
913	* by prog_fd, and the stream is identified by the stream_id.
914	* The data is copied to a buffer pointed to by stream_buf, and
915	* filled less than or equal to stream_buf_len bytes.
916	*
917	* Return
918	* Number of bytes read from the stream on success, or -1 if an
919	* error occurred (in which case, errno is set appropriately).
920	*
921	* NOTES
922	* eBPF objects (maps and programs) can be shared between processes.
923	*
924	* * After fork\ (2), the child inherits file descriptors
925	* referring to the same eBPF objects.
926	* * File descriptors referring to eBPF objects can be transferred over
927	* unix\ (7) domain sockets.
928	* * File descriptors referring to eBPF objects can be duplicated in the
929	* usual way, using dup\ (2) and similar calls.
930	* * File descriptors referring to eBPF objects can be pinned to the
931	* filesystem using the BPF_OBJ_PIN command of bpf\ (2).
932	*
933	* An eBPF object is deallocated only after all file descriptors referring
934	* to the object have been closed and no references remain pinned to the
935	* filesystem or attached (for example, bound to a program or device).
936	*/
937	enum bpf_cmd {
938	BPF_MAP_CREATE,
939	BPF_MAP_LOOKUP_ELEM,
940	BPF_MAP_UPDATE_ELEM,
941	BPF_MAP_DELETE_ELEM,
942	BPF_MAP_GET_NEXT_KEY,
943	BPF_PROG_LOAD,
944	BPF_OBJ_PIN,
945	BPF_OBJ_GET,
946	BPF_PROG_ATTACH,
947	BPF_PROG_DETACH,
948	BPF_PROG_TEST_RUN,
949	BPF_PROG_RUN = BPF_PROG_TEST_RUN,
950	BPF_PROG_GET_NEXT_ID,
951	BPF_MAP_GET_NEXT_ID,
952	BPF_PROG_GET_FD_BY_ID,
953	BPF_MAP_GET_FD_BY_ID,
954	BPF_OBJ_GET_INFO_BY_FD,
955	BPF_PROG_QUERY,
956	BPF_RAW_TRACEPOINT_OPEN,
957	BPF_BTF_LOAD,
958	BPF_BTF_GET_FD_BY_ID,
959	BPF_TASK_FD_QUERY,
960	BPF_MAP_LOOKUP_AND_DELETE_ELEM,
961	BPF_MAP_FREEZE,
962	BPF_BTF_GET_NEXT_ID,
963	BPF_MAP_LOOKUP_BATCH,
964	BPF_MAP_LOOKUP_AND_DELETE_BATCH,
965	BPF_MAP_UPDATE_BATCH,
966	BPF_MAP_DELETE_BATCH,
967	BPF_LINK_CREATE,
968	BPF_LINK_UPDATE,
969	BPF_LINK_GET_FD_BY_ID,
970	BPF_LINK_GET_NEXT_ID,
971	BPF_ENABLE_STATS,
972	BPF_ITER_CREATE,
973	BPF_LINK_DETACH,
974	BPF_PROG_BIND_MAP,
975	BPF_TOKEN_CREATE,
976	BPF_PROG_STREAM_READ_BY_FD,
977	__MAX_BPF_CMD,
978	};
979
980	enum bpf_map_type {
981	BPF_MAP_TYPE_UNSPEC,
982	BPF_MAP_TYPE_HASH,
983	BPF_MAP_TYPE_ARRAY,
984	BPF_MAP_TYPE_PROG_ARRAY,
985	BPF_MAP_TYPE_PERF_EVENT_ARRAY,
986	BPF_MAP_TYPE_PERCPU_HASH,
987	BPF_MAP_TYPE_PERCPU_ARRAY,
988	BPF_MAP_TYPE_STACK_TRACE,
989	BPF_MAP_TYPE_CGROUP_ARRAY,
990	BPF_MAP_TYPE_LRU_HASH,
991	BPF_MAP_TYPE_LRU_PERCPU_HASH,
992	BPF_MAP_TYPE_LPM_TRIE,
993	BPF_MAP_TYPE_ARRAY_OF_MAPS,
994	BPF_MAP_TYPE_HASH_OF_MAPS,
995	BPF_MAP_TYPE_DEVMAP,
996	BPF_MAP_TYPE_SOCKMAP,
997	BPF_MAP_TYPE_CPUMAP,
998	BPF_MAP_TYPE_XSKMAP,
999	BPF_MAP_TYPE_SOCKHASH,
1000	BPF_MAP_TYPE_CGROUP_STORAGE_DEPRECATED,
1001	/ BPF_MAP_TYPE_CGROUP_STORAGE is available to bpf programs attaching*
1002	* to a cgroup. The newer BPF_MAP_TYPE_CGRP_STORAGE is available to
1003	* both cgroup-attached and other progs and supports all functionality
1004	* provided by BPF_MAP_TYPE_CGROUP_STORAGE. So mark
1005	* BPF_MAP_TYPE_CGROUP_STORAGE deprecated.
1006	*/
1007	BPF_MAP_TYPE_CGROUP_STORAGE = BPF_MAP_TYPE_CGROUP_STORAGE_DEPRECATED,
1008	BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
1009	BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE_DEPRECATED,
1010	/ BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE is available to bpf programs*
1011	* attaching to a cgroup. The new mechanism (BPF_MAP_TYPE_CGRP_STORAGE +
1012	* local percpu kptr) supports all BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE
1013	* functionality and more. So mark * BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE
1014	* deprecated.
1015	*/
1016	BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE = BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE_DEPRECATED,
1017	BPF_MAP_TYPE_QUEUE,
1018	BPF_MAP_TYPE_STACK,
1019	BPF_MAP_TYPE_SK_STORAGE,
1020	BPF_MAP_TYPE_DEVMAP_HASH,
1021	BPF_MAP_TYPE_STRUCT_OPS,
1022	BPF_MAP_TYPE_RINGBUF,
1023	BPF_MAP_TYPE_INODE_STORAGE,
1024	BPF_MAP_TYPE_TASK_STORAGE,
1025	BPF_MAP_TYPE_BLOOM_FILTER,
1026	BPF_MAP_TYPE_USER_RINGBUF,
1027	BPF_MAP_TYPE_CGRP_STORAGE,
1028	BPF_MAP_TYPE_ARENA,
1029	__MAX_BPF_MAP_TYPE
1030	};
1031
1032	/ Note that tracing related programs such as*
1033	* BPF_PROG_TYPE_{KPROBE,TRACEPOINT,PERF_EVENT,RAW_TRACEPOINT}
1034	* are not subject to a stable API since kernel internal data
1035	* structures can change from release to release and may
1036	* therefore break existing tracing BPF programs. Tracing BPF
1037	* programs correspond to /a/ specific kernel which is to be
1038	* analyzed, and not /a/ specific kernel /and/ all future ones.
1039	*/
1040	enum bpf_prog_type {
1041	BPF_PROG_TYPE_UNSPEC,
1042	BPF_PROG_TYPE_SOCKET_FILTER,
1043	BPF_PROG_TYPE_KPROBE,
1044	BPF_PROG_TYPE_SCHED_CLS,
1045	BPF_PROG_TYPE_SCHED_ACT,
1046	BPF_PROG_TYPE_TRACEPOINT,
1047	BPF_PROG_TYPE_XDP,
1048	BPF_PROG_TYPE_PERF_EVENT,
1049	BPF_PROG_TYPE_CGROUP_SKB,
1050	BPF_PROG_TYPE_CGROUP_SOCK,
1051	BPF_PROG_TYPE_LWT_IN,
1052	BPF_PROG_TYPE_LWT_OUT,
1053	BPF_PROG_TYPE_LWT_XMIT,
1054	BPF_PROG_TYPE_SOCK_OPS,
1055	BPF_PROG_TYPE_SK_SKB,
1056	BPF_PROG_TYPE_CGROUP_DEVICE,
1057	BPF_PROG_TYPE_SK_MSG,
1058	BPF_PROG_TYPE_RAW_TRACEPOINT,
1059	BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
1060	BPF_PROG_TYPE_LWT_SEG6LOCAL,
1061	BPF_PROG_TYPE_LIRC_MODE2,
1062	BPF_PROG_TYPE_SK_REUSEPORT,
1063	BPF_PROG_TYPE_FLOW_DISSECTOR,
1064	BPF_PROG_TYPE_CGROUP_SYSCTL,
1065	BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
1066	BPF_PROG_TYPE_CGROUP_SOCKOPT,
1067	BPF_PROG_TYPE_TRACING,
1068	BPF_PROG_TYPE_STRUCT_OPS,
1069	BPF_PROG_TYPE_EXT,
1070	BPF_PROG_TYPE_LSM,
1071	BPF_PROG_TYPE_SK_LOOKUP,
1072	BPF_PROG_TYPE_SYSCALL, / a program that can execute syscalls /
1073	BPF_PROG_TYPE_NETFILTER,
1074	__MAX_BPF_PROG_TYPE
1075	};
1076
1077	enum bpf_attach_type {
1078	BPF_CGROUP_INET_INGRESS,
1079	BPF_CGROUP_INET_EGRESS,
1080	BPF_CGROUP_INET_SOCK_CREATE,
1081	BPF_CGROUP_SOCK_OPS,
1082	BPF_SK_SKB_STREAM_PARSER,
1083	BPF_SK_SKB_STREAM_VERDICT,
1084	BPF_CGROUP_DEVICE,
1085	BPF_SK_MSG_VERDICT,
1086	BPF_CGROUP_INET4_BIND,
1087	BPF_CGROUP_INET6_BIND,
1088	BPF_CGROUP_INET4_CONNECT,
1089	BPF_CGROUP_INET6_CONNECT,
1090	BPF_CGROUP_INET4_POST_BIND,
1091	BPF_CGROUP_INET6_POST_BIND,
1092	BPF_CGROUP_UDP4_SENDMSG,
1093	BPF_CGROUP_UDP6_SENDMSG,
1094	BPF_LIRC_MODE2,
1095	BPF_FLOW_DISSECTOR,
1096	BPF_CGROUP_SYSCTL,
1097	BPF_CGROUP_UDP4_RECVMSG,
1098	BPF_CGROUP_UDP6_RECVMSG,
1099	BPF_CGROUP_GETSOCKOPT,
1100	BPF_CGROUP_SETSOCKOPT,
1101	BPF_TRACE_RAW_TP,
1102	BPF_TRACE_FENTRY,
1103	BPF_TRACE_FEXIT,
1104	BPF_MODIFY_RETURN,
1105	BPF_LSM_MAC,
1106	BPF_TRACE_ITER,
1107	BPF_CGROUP_INET4_GETPEERNAME,
1108	BPF_CGROUP_INET6_GETPEERNAME,
1109	BPF_CGROUP_INET4_GETSOCKNAME,
1110	BPF_CGROUP_INET6_GETSOCKNAME,
1111	BPF_XDP_DEVMAP,
1112	BPF_CGROUP_INET_SOCK_RELEASE,
1113	BPF_XDP_CPUMAP,
1114	BPF_SK_LOOKUP,
1115	BPF_XDP,
1116	BPF_SK_SKB_VERDICT,
1117	BPF_SK_REUSEPORT_SELECT,
1118	BPF_SK_REUSEPORT_SELECT_OR_MIGRATE,
1119	BPF_PERF_EVENT,
1120	BPF_TRACE_KPROBE_MULTI,
1121	BPF_LSM_CGROUP,
1122	BPF_STRUCT_OPS,
1123	BPF_NETFILTER,
1124	BPF_TCX_INGRESS,
1125	BPF_TCX_EGRESS,
1126	BPF_TRACE_UPROBE_MULTI,
1127	BPF_CGROUP_UNIX_CONNECT,
1128	BPF_CGROUP_UNIX_SENDMSG,
1129	BPF_CGROUP_UNIX_RECVMSG,
1130	BPF_CGROUP_UNIX_GETPEERNAME,
1131	BPF_CGROUP_UNIX_GETSOCKNAME,
1132	BPF_NETKIT_PRIMARY,
1133	BPF_NETKIT_PEER,
1134	BPF_TRACE_KPROBE_SESSION,
1135	BPF_TRACE_UPROBE_SESSION,
1136	__MAX_BPF_ATTACH_TYPE
1137	};
1138
1139	#define MAX_BPF_ATTACH_TYPE __MAX_BPF_ATTACH_TYPE
1140
1141	/ Add BPF_LINK_TYPE(type, name) in bpf_types.h to keep bpf_link_type_strs[]*
1142	* in sync with the definitions below.
1143	*/
1144	enum bpf_link_type {
1145	BPF_LINK_TYPE_UNSPEC = `0`,
1146	BPF_LINK_TYPE_RAW_TRACEPOINT = `1`,
1147	BPF_LINK_TYPE_TRACING = `2`,
1148	BPF_LINK_TYPE_CGROUP = `3`,
1149	BPF_LINK_TYPE_ITER = `4`,
1150	BPF_LINK_TYPE_NETNS = `5`,
1151	BPF_LINK_TYPE_XDP = `6`,
1152	BPF_LINK_TYPE_PERF_EVENT = `7`,
1153	BPF_LINK_TYPE_KPROBE_MULTI = `8`,
1154	BPF_LINK_TYPE_STRUCT_OPS = `9`,
1155	BPF_LINK_TYPE_NETFILTER = `10`,
1156	BPF_LINK_TYPE_TCX = `11`,
1157	BPF_LINK_TYPE_UPROBE_MULTI = `12`,
1158	BPF_LINK_TYPE_NETKIT = `13`,
1159	BPF_LINK_TYPE_SOCKMAP = `14`,
1160	__MAX_BPF_LINK_TYPE,
1161	};
1162
1163	#define MAX_BPF_LINK_TYPE __MAX_BPF_LINK_TYPE
1164
1165	enum bpf_perf_event_type {
1166	BPF_PERF_EVENT_UNSPEC = `0`,
1167	BPF_PERF_EVENT_UPROBE = `1`,
1168	BPF_PERF_EVENT_URETPROBE = `2`,
1169	BPF_PERF_EVENT_KPROBE = `3`,
1170	BPF_PERF_EVENT_KRETPROBE = `4`,
1171	BPF_PERF_EVENT_TRACEPOINT = `5`,
1172	BPF_PERF_EVENT_EVENT = `6`,
1173	};
1174
1175	/ cgroup-bpf attach flags used in BPF_PROG_ATTACH command*
1176	*
1177	* NONE(default): No further bpf programs allowed in the subtree.
1178	*
1179	* BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program,
1180	* the program in this cgroup yields to sub-cgroup program.
1181	*
1182	* BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program,
1183	* that cgroup program gets run in addition to the program in this cgroup.
1184	*
1185	* Only one program is allowed to be attached to a cgroup with
1186	* NONE or BPF_F_ALLOW_OVERRIDE flag.
1187	* Attaching another program on top of NONE or BPF_F_ALLOW_OVERRIDE will
1188	* release old program and attach the new one. Attach flags has to match.
1189	*
1190	* Multiple programs are allowed to be attached to a cgroup with
1191	* BPF_F_ALLOW_MULTI flag. They are executed in FIFO order
1192	* (those that were attached first, run first)
1193	* The programs of sub-cgroup are executed first, then programs of
1194	* this cgroup and then programs of parent cgroup.
1195	* When children program makes decision (like picking TCP CA or sock bind)
1196	* parent program has a chance to override it.
1197	*
1198	* With BPF_F_ALLOW_MULTI a new program is added to the end of the list of
1199	* programs for a cgroup. Though it's possible to replace an old program at
1200	* any position by also specifying BPF_F_REPLACE flag and position itself in
1201	* replace_bpf_fd attribute. Old program at this position will be released.
1202	*
1203	* A cgroup with MULTI or OVERRIDE flag allows any attach flags in sub-cgroups.
1204	* A cgroup with NONE doesn't allow any programs in sub-cgroups.
1205	* Ex1:
1206	* cgrp1 (MULTI progs A, B) ->
1207	* cgrp2 (OVERRIDE prog C) ->
1208	* cgrp3 (MULTI prog D) ->
1209	* cgrp4 (OVERRIDE prog E) ->
1210	* cgrp5 (NONE prog F)
1211	* the event in cgrp5 triggers execution of F,D,A,B in that order.
1212	* if prog F is detached, the execution is E,D,A,B
1213	* if prog F and D are detached, the execution is E,A,B
1214	* if prog F, E and D are detached, the execution is C,A,B
1215	*
1216	* All eligible programs are executed regardless of return code from
1217	* earlier programs.
1218	*/
1219	#define BPF_F_ALLOW_OVERRIDE (1U << 0)
1220	#define BPF_F_ALLOW_MULTI (1U << 1)
1221	/ Generic attachment flags. /
1222	#define BPF_F_REPLACE (1U << 2)
1223	#define BPF_F_BEFORE (1U << 3)
1224	#define BPF_F_AFTER (1U << 4)
1225	#define BPF_F_ID (1U << 5)
1226	#define BPF_F_PREORDER (1U << 6)
1227	#define BPF_F_LINK BPF_F_LINK /* 1 << 13 */
1228
1229	/ If BPF_F_STRICT_ALIGNMENT is used in BPF_PROG_LOAD command, the*
1230	* verifier will perform strict alignment checking as if the kernel
1231	* has been built with CONFIG_EFFICIENT_UNALIGNED_ACCESS not set,
1232	* and NET_IP_ALIGN defined to 2.
1233	*/
1234	#define BPF_F_STRICT_ALIGNMENT (1U << 0)
1235
1236	/ If BPF_F_ANY_ALIGNMENT is used in BPF_PROG_LOAD command, the*
1237	* verifier will allow any alignment whatsoever. On platforms
1238	* with strict alignment requirements for loads ands stores (such
1239	* as sparc and mips) the verifier validates that all loads and
1240	* stores provably follow this requirement. This flag turns that
1241	* checking and enforcement off.
1242	*
1243	* It is mostly used for testing when we want to validate the
1244	* context and memory access aspects of the verifier, but because
1245	* of an unaligned access the alignment check would trigger before
1246	* the one we are interested in.
1247	*/
1248	#define BPF_F_ANY_ALIGNMENT (1U << 1)
1249
1250	/ BPF_F_TEST_RND_HI32 is used in BPF_PROG_LOAD command for testing purpose.*
1251	* Verifier does sub-register def/use analysis and identifies instructions whose
1252	* def only matters for low 32-bit, high 32-bit is never referenced later
1253	* through implicit zero extension. Therefore verifier notifies JIT back-ends
1254	* that it is safe to ignore clearing high 32-bit for these instructions. This
1255	* saves some back-ends a lot of code-gen. However such optimization is not
1256	* necessary on some arches, for example x86_64, arm64 etc, whose JIT back-ends
1257	* hence hasn't used verifier's analysis result. But, we really want to have a
1258	* way to be able to verify the correctness of the described optimization on
1259	* x86_64 on which testsuites are frequently exercised.
1260	*
1261	* So, this flag is introduced. Once it is set, verifier will randomize high
1262	* 32-bit for those instructions who has been identified as safe to ignore them.
1263	* Then, if verifier is not doing correct analysis, such randomization will
1264	* regress tests to expose bugs.
1265	*/
1266	#define BPF_F_TEST_RND_HI32 (1U << 2)
1267
1268	/ The verifier internal test flag. Behavior is undefined /
1269	#define BPF_F_TEST_STATE_FREQ (1U << 3)
1270
1271	/ If BPF_F_SLEEPABLE is used in BPF_PROG_LOAD command, the verifier will*
1272	* restrict map and helper usage for such programs. Sleepable BPF programs can
1273	* only be attached to hooks where kernel execution context allows sleeping.
1274	* Such programs are allowed to use helpers that may sleep like
1275	* bpf_copy_from_user().
1276	*/
1277	#define BPF_F_SLEEPABLE (1U << 4)
1278
1279	/ If BPF_F_XDP_HAS_FRAGS is used in BPF_PROG_LOAD command, the loaded program*
1280	* fully support xdp frags.
1281	*/
1282	#define BPF_F_XDP_HAS_FRAGS (1U << 5)
1283
1284	/ If BPF_F_XDP_DEV_BOUND_ONLY is used in BPF_PROG_LOAD command, the loaded*
1285	* program becomes device-bound but can access XDP metadata.
1286	*/
1287	#define BPF_F_XDP_DEV_BOUND_ONLY (1U << 6)
1288
1289	/ The verifier internal test flag. Behavior is undefined /
1290	#define BPF_F_TEST_REG_INVARIANTS (1U << 7)
1291
1292	/ link_create.kprobe_multi.flags used in LINK_CREATE command for*
1293	* BPF_TRACE_KPROBE_MULTI attach type to create return probe.
1294	*/
1295	enum {
1296	BPF_F_KPROBE_MULTI_RETURN = (`1U` << `0`)
1297	};
1298
1299	/ link_create.uprobe_multi.flags used in LINK_CREATE command for*
1300	* BPF_TRACE_UPROBE_MULTI attach type to create return probe.
1301	*/
1302	enum {
1303	BPF_F_UPROBE_MULTI_RETURN = (`1U` << `0`)
1304	};
1305
1306	/ link_create.netfilter.flags used in LINK_CREATE command for*
1307	* BPF_PROG_TYPE_NETFILTER to enable IP packet defragmentation.
1308	*/
1309	#define BPF_F_NETFILTER_IP_DEFRAG (1U << 0)
1310
1311	/ When BPF ldimm64's insn[0].src_reg != 0 then this can have*
1312	* the following extensions:
1313	*
1314	* insn[0].src_reg: BPF_PSEUDO_MAP_[FD\|IDX]
1315	* insn[0].imm: map fd or fd_idx
1316	* insn[1].imm: 0
1317	* insn[0].off: 0
1318	* insn[1].off: 0
1319	* ldimm64 rewrite: address of map
1320	* verifier type: CONST_PTR_TO_MAP
1321	*/
1322	#define BPF_PSEUDO_MAP_FD 1
1323	#define BPF_PSEUDO_MAP_IDX 5
1324
1325	/ insn[0].src_reg: BPF_PSEUDO_MAP_[IDX_]VALUE*
1326	* insn[0].imm: map fd or fd_idx
1327	* insn[1].imm: offset into value
1328	* insn[0].off: 0
1329	* insn[1].off: 0
1330	* ldimm64 rewrite: address of map[0]+offset
1331	* verifier type: PTR_TO_MAP_VALUE
1332	*/
1333	#define BPF_PSEUDO_MAP_VALUE 2
1334	#define BPF_PSEUDO_MAP_IDX_VALUE 6
1335
1336	/ insn[0].src_reg: BPF_PSEUDO_BTF_ID*
1337	* insn[0].imm: kernel btd id of VAR
1338	* insn[1].imm: 0
1339	* insn[0].off: 0
1340	* insn[1].off: 0
1341	* ldimm64 rewrite: address of the kernel variable
1342	* verifier type: PTR_TO_BTF_ID or PTR_TO_MEM, depending on whether the var
1343	* is struct/union.
1344	*/
1345	#define BPF_PSEUDO_BTF_ID 3
1346	/ insn[0].src_reg: BPF_PSEUDO_FUNC*
1347	* insn[0].imm: insn offset to the func
1348	* insn[1].imm: 0
1349	* insn[0].off: 0
1350	* insn[1].off: 0
1351	* ldimm64 rewrite: address of the function
1352	* verifier type: PTR_TO_FUNC.
1353	*/
1354	#define BPF_PSEUDO_FUNC 4
1355
1356	/ when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative*
1357	* offset to another bpf function
1358	*/
1359	#define BPF_PSEUDO_CALL 1
1360	/ when bpf_call->src_reg == BPF_PSEUDO_KFUNC_CALL,*
1361	* bpf_call->imm == btf_id of a BTF_KIND_FUNC in the running kernel
1362	*/
1363	#define BPF_PSEUDO_KFUNC_CALL 2
1364
1365	enum bpf_addr_space_cast {
1366	BPF_ADDR_SPACE_CAST = `1`,
1367	};
1368
1369	/ flags for BPF_MAP_UPDATE_ELEM command /
1370	enum {
1371	BPF_ANY = `0`, / create new element or update existing /
1372	BPF_NOEXIST = `1`, / create new element if it didn't exist /
1373	BPF_EXIST = `2`, / update existing element /
1374	BPF_F_LOCK = `4`, / spin_lock-ed map_lookup/map_update /
1375	};
1376
1377	/ flags for BPF_MAP_CREATE command /
1378	enum {
1379	BPF_F_NO_PREALLOC = (`1U` << `0`),
1380	/ Instead of having one common LRU list in the*
1381	* BPF_MAP_TYPE_LRU_[PERCPU_]HASH map, use a percpu LRU list
1382	* which can scale and perform better.
1383	* Note, the LRU nodes (including free nodes) cannot be moved
1384	* across different LRU lists.
1385	*/
1386	BPF_F_NO_COMMON_LRU = (`1U` << `1`),
1387	/ Specify numa node during map creation /
1388	BPF_F_NUMA_NODE = (`1U` << `2`),
1389
1390	/ Flags for accessing BPF object from syscall side. /
1391	BPF_F_RDONLY = (`1U` << `3`),
1392	BPF_F_WRONLY = (`1U` << `4`),
1393
1394	/ Flag for stack_map, store build_id+offset instead of pointer /
1395	BPF_F_STACK_BUILD_ID = (`1U` << `5`),
1396
1397	/ Zero-initialize hash function seed. This should only be used for testing. /
1398	BPF_F_ZERO_SEED = (`1U` << `6`),
1399
1400	/ Flags for accessing BPF object from program side. /
1401	BPF_F_RDONLY_PROG = (`1U` << `7`),
1402	BPF_F_WRONLY_PROG = (`1U` << `8`),
1403
1404	/ Clone map from listener for newly accepted socket /
1405	BPF_F_CLONE = (`1U` << `9`),
1406
1407	/ Enable memory-mapping BPF map /
1408	BPF_F_MMAPABLE = (`1U` << `10`),
1409
1410	/ Share perf_event among processes /
1411	BPF_F_PRESERVE_ELEMS = (`1U` << `11`),
1412
1413	/ Create a map that is suitable to be an inner map with dynamic max entries /
1414	BPF_F_INNER_MAP = (`1U` << `12`),
1415
1416	/ Create a map that will be registered/unregesitered by the backed bpf_link /
1417	BPF_F_LINK = (`1U` << `13`),
1418
1419	/ Get path from provided FD in BPF_OBJ_PIN/BPF_OBJ_GET commands /
1420	BPF_F_PATH_FD = (`1U` << `14`),
1421
1422	/ Flag for value_type_btf_obj_fd, the fd is available /
1423	BPF_F_VTYPE_BTF_OBJ_FD = (`1U` << `15`),
1424
1425	/ BPF token FD is passed in a corresponding command's token_fd field /
1426	BPF_F_TOKEN_FD = (`1U` << `16`),
1427
1428	/ When user space page faults in bpf_arena send SIGSEGV instead of inserting new page /
1429	BPF_F_SEGV_ON_FAULT = (`1U` << `17`),
1430
1431	/ Do not translate kernel bpf_arena pointers to user pointers /
1432	BPF_F_NO_USER_CONV = (`1U` << `18`),
1433	};
1434
1435	/ Flags for BPF_PROG_QUERY. /
1436
1437	/ Query effective (directly attached + inherited from ancestor cgroups)*
1438	* programs that will be executed for events within a cgroup.
1439	* attach_flags with this flag are always returned 0.
1440	*/
1441	#define BPF_F_QUERY_EFFECTIVE (1U << 0)
1442
1443	/ Flags for BPF_PROG_TEST_RUN /
1444
1445	/ If set, run the test on the cpu specified by bpf_attr.test.cpu /
1446	#define BPF_F_TEST_RUN_ON_CPU (1U << 0)
1447	/ If set, XDP frames will be transmitted after processing /
1448	#define BPF_F_TEST_XDP_LIVE_FRAMES (1U << 1)
1449	/ If set, apply CHECKSUM_COMPLETE to skb and validate the checksum /
1450	#define BPF_F_TEST_SKB_CHECKSUM_COMPLETE (1U << 2)
1451
1452	/ type for BPF_ENABLE_STATS /
1453	enum bpf_stats_type {
1454	/ enabled run_time_ns and run_cnt /
1455	BPF_STATS_RUN_TIME = `0`,
1456	};
1457
1458	enum bpf_stack_build_id_status {
1459	/ user space need an empty entry to identify end of a trace /
1460	BPF_STACK_BUILD_ID_EMPTY = `0`,
1461	/ with valid build_id and offset /
1462	BPF_STACK_BUILD_ID_VALID = `1`,
1463	/ couldn't get build_id, fallback to ip /
1464	BPF_STACK_BUILD_ID_IP = `2`,
1465	};
1466
1467	#define BPF_BUILD_ID_SIZE 20
1468	struct bpf_stack_build_id {
1469	__s32 status;
1470	unsigned char build_id[BPF_BUILD_ID_SIZE];
1471	union {
1472	__u64 offset;
1473	__u64 ip;
1474	};
1475	};
1476
1477	#define BPF_OBJ_NAME_LEN 16U
1478
1479	enum {
1480	BPF_STREAM_STDOUT = `1`,
1481	BPF_STREAM_STDERR = `2`,
1482	};
1483
1484	union bpf_attr {
1485	struct { / anonymous struct used by BPF_MAP_CREATE command /
1486	__u32 map_type; / one of enum bpf_map_type /
1487	__u32 key_size; / size of key in bytes /
1488	__u32 value_size; / size of value in bytes /
1489	__u32 max_entries; / max number of entries in a map /
1490	__u32 map_flags; / BPF_MAP_CREATE related*
1491	* flags defined above.
1492	*/
1493	__u32 inner_map_fd; / fd pointing to the inner map /
1494	__u32 numa_node; / numa node (effective only if*
1495	* BPF_F_NUMA_NODE is set).
1496	*/
1497	char map_name[BPF_OBJ_NAME_LEN];
1498	__u32 map_ifindex; / ifindex of netdev to create on /
1499	__u32 btf_fd; / fd pointing to a BTF type data /
1500	__u32 btf_key_type_id; / BTF type_id of the key /
1501	__u32 btf_value_type_id; / BTF type_id of the value /
1502	__u32 btf_vmlinux_value_type_id;/ BTF type_id of a kernel-*
1503	* struct stored as the
1504	* map value
1505	*/
1506	/ Any per-map-type extra fields*
1507	*
1508	* BPF_MAP_TYPE_BLOOM_FILTER - the lowest 4 bits indicate the
1509	* number of hash functions (if 0, the bloom filter will default
1510	* to using 5 hash functions).
1511	*
1512	* BPF_MAP_TYPE_ARENA - contains the address where user space
1513	* is going to mmap() the arena. It has to be page aligned.
1514	*/
1515	__u64 map_extra;
1516
1517	__s32 value_type_btf_obj_fd; / fd pointing to a BTF*
1518	* type data for
1519	* btf_vmlinux_value_type_id.
1520	*/
1521	/ BPF token FD to use with BPF_MAP_CREATE operation.*
1522	* If provided, map_flags should have BPF_F_TOKEN_FD flag set.
1523	*/
1524	__s32 map_token_fd;
1525
1526	/ Hash of the program that has exclusive access to the map.*
1527	*/
1528	__aligned_u64 excl_prog_hash;
1529	/ Size of the passed excl_prog_hash. /
1530	__u32 excl_prog_hash_size;
1531	};
1532
1533	struct { / anonymous struct used by BPF_MAP__ELEM and BPF_MAP_FREEZE commands /*
1534	__u32 map_fd;
1535	__aligned_u64 key;
1536	union {
1537	__aligned_u64 value;
1538	__aligned_u64 next_key;
1539	};
1540	__u64 flags;
1541	};
1542
1543	struct { / struct used by BPF_MAP__BATCH commands /*
1544	__aligned_u64 in_batch; / start batch,*
1545	* NULL to start from beginning
1546	*/
1547	__aligned_u64 out_batch; / output: next start batch /
1548	__aligned_u64 keys;
1549	__aligned_u64 values;
1550	__u32 count; / input/output:*
1551	* input: # of key/value
1552	* elements
1553	* output: # of filled elements
1554	*/
1555	__u32 map_fd;
1556	__u64 elem_flags;
1557	__u64 flags;
1558	} batch;
1559
1560	struct { / anonymous struct used by BPF_PROG_LOAD command /
1561	__u32 prog_type; / one of enum bpf_prog_type /
1562	__u32 insn_cnt;
1563	__aligned_u64 insns;
1564	__aligned_u64 license;
1565	__u32 log_level; / verbosity level of verifier /
1566	__u32 log_size; / size of user buffer /
1567	__aligned_u64 log_buf; / user supplied buffer /
1568	__u32 kern_version; / not used /
1569	__u32 prog_flags;
1570	char prog_name[BPF_OBJ_NAME_LEN];
1571	__u32 prog_ifindex; / ifindex of netdev to prep for /
1572	/ For some prog types expected attach type must be known at*
1573	* load time to verify attach type specific parts of prog
1574	* (context accesses, allowed helpers, etc).
1575	*/
1576	__u32 expected_attach_type;
1577	__u32 prog_btf_fd; / fd pointing to BTF type data /
1578	__u32 func_info_rec_size; / userspace bpf_func_info size /
1579	__aligned_u64 func_info; / func info /
1580	__u32 func_info_cnt; / number of bpf_func_info records /
1581	__u32 line_info_rec_size; / userspace bpf_line_info size /
1582	__aligned_u64 line_info; / line info /
1583	__u32 line_info_cnt; / number of bpf_line_info records /
1584	__u32 attach_btf_id; / in-kernel BTF type id to attach to /
1585	union {
1586	/ valid prog_fd to attach to bpf prog /
1587	__u32 attach_prog_fd;
1588	/ or valid module BTF object fd or 0 to attach to vmlinux /
1589	__u32 attach_btf_obj_fd;
1590	};
1591	__u32 core_relo_cnt; / number of bpf_core_relo /
1592	__aligned_u64 fd_array; / array of FDs /
1593	__aligned_u64 core_relos;
1594	__u32 core_relo_rec_size; / sizeof(struct bpf_core_relo) /
1595	/ output: actual total log contents size (including termintaing zero).*
1596	* It could be both larger than original log_size (if log was
1597	* truncated), or smaller (if log buffer wasn't filled completely).
1598	*/
1599	__u32 log_true_size;
1600	/ BPF token FD to use with BPF_PROG_LOAD operation.*
1601	* If provided, prog_flags should have BPF_F_TOKEN_FD flag set.
1602	*/
1603	__s32 prog_token_fd;
1604	/ The fd_array_cnt can be used to pass the length of the*
1605	* fd_array array. In this case all the [map] file descriptors
1606	* passed in this array will be bound to the program, even if
1607	* the maps are not referenced directly. The functionality is
1608	* similar to the BPF_PROG_BIND_MAP syscall, but maps can be
1609	* used by the verifier during the program load. If provided,
1610	* then the fd_array[0,...,fd_array_cnt-1] is expected to be
1611	* continuous.
1612	*/
1613	__u32 fd_array_cnt;
1614	/ Pointer to a buffer containing the signature of the BPF*
1615	* program.
1616	*/
1617	__aligned_u64 signature;
1618	/ Size of the signature buffer in bytes. /
1619	__u32 signature_size;
1620	/ ID of the kernel keyring to be used for signature*
1621	* verification.
1622	*/
1623	__s32 keyring_id;
1624	};
1625
1626	struct { / anonymous struct used by BPF_OBJ_* commands /
1627	__aligned_u64 pathname;
1628	__u32 bpf_fd;
1629	__u32 file_flags;
1630	/ Same as dirfd in openat() syscall; see openat(2)*
1631	* manpage for details of path FD and pathname semantics;
1632	* path_fd should accompanied by BPF_F_PATH_FD flag set in
1633	* file_flags field, otherwise it should be set to zero;
1634	* if BPF_F_PATH_FD flag is not set, AT_FDCWD is assumed.
1635	*/
1636	__s32 path_fd;
1637	};
1638
1639	struct { / anonymous struct used by BPF_PROG_ATTACH/DETACH commands /
1640	union {
1641	__u32 target_fd; / target object to attach to or ... /
1642	__u32 target_ifindex; / target ifindex /
1643	};
1644	__u32 attach_bpf_fd;
1645	__u32 attach_type;
1646	__u32 attach_flags;
1647	__u32 replace_bpf_fd;
1648	union {
1649	__u32 relative_fd;
1650	__u32 relative_id;
1651	};
1652	__u64 expected_revision;
1653	};
1654
1655	struct { / anonymous struct used by BPF_PROG_TEST_RUN command /
1656	__u32 prog_fd;
1657	__u32 retval;
1658	__u32 data_size_in; / input: len of data_in /
1659	__u32 data_size_out; / input/output: len of data_out*
1660	* returns ENOSPC if data_out
1661	* is too small.
1662	*/
1663	__aligned_u64 data_in;
1664	__aligned_u64 data_out;
1665	__u32 repeat;
1666	__u32 duration;
1667	__u32 ctx_size_in; / input: len of ctx_in /
1668	__u32 ctx_size_out; / input/output: len of ctx_out*
1669	* returns ENOSPC if ctx_out
1670	* is too small.
1671	*/
1672	__aligned_u64 ctx_in;
1673	__aligned_u64 ctx_out;
1674	__u32 flags;
1675	__u32 cpu;
1676	__u32 batch_size;
1677	} test;
1678
1679	struct { / anonymous struct used by BPF__GET__ID /
1680	union {
1681	__u32 start_id;
1682	__u32 prog_id;
1683	__u32 map_id;
1684	__u32 btf_id;
1685	__u32 link_id;
1686	};
1687	__u32 next_id;
1688	__u32 open_flags;
1689	__s32 fd_by_id_token_fd;
1690	};
1691
1692	struct { / anonymous struct used by BPF_OBJ_GET_INFO_BY_FD /
1693	__u32 bpf_fd;
1694	__u32 info_len;
1695	__aligned_u64 info;
1696	} info;
1697
1698	struct { / anonymous struct used by BPF_PROG_QUERY command /
1699	union {
1700	__u32 target_fd; / target object to query or ... /
1701	__u32 target_ifindex; / target ifindex /
1702	};
1703	__u32 attach_type;
1704	__u32 query_flags;
1705	__u32 attach_flags;
1706	__aligned_u64 prog_ids;
1707	union {
1708	__u32 prog_cnt;
1709	__u32 count;
1710	};
1711	__u32 :`32`;
1712	/ output: per-program attach_flags.*
1713	* not allowed to be set during effective query.
1714	*/
1715	__aligned_u64 prog_attach_flags;
1716	__aligned_u64 link_ids;
1717	__aligned_u64 link_attach_flags;
1718	__u64 revision;
1719	} query;
1720
1721	struct { / anonymous struct used by BPF_RAW_TRACEPOINT_OPEN command /
1722	__u64 name;
1723	__u32 prog_fd;
1724	__u32 :`32`;
1725	__aligned_u64 cookie;
1726	} raw_tracepoint;
1727
1728	struct { / anonymous struct for BPF_BTF_LOAD /
1729	__aligned_u64 btf;
1730	__aligned_u64 btf_log_buf;
1731	__u32 btf_size;
1732	__u32 btf_log_size;
1733	__u32 btf_log_level;
1734	/ output: actual total log contents size (including termintaing zero).*
1735	* It could be both larger than original log_size (if log was
1736	* truncated), or smaller (if log buffer wasn't filled completely).
1737	*/
1738	__u32 btf_log_true_size;
1739	__u32 btf_flags;
1740	/ BPF token FD to use with BPF_BTF_LOAD operation.*
1741	* If provided, btf_flags should have BPF_F_TOKEN_FD flag set.
1742	*/
1743	__s32 btf_token_fd;
1744	};
1745
1746	struct {
1747	__u32 pid; / input: pid /
1748	__u32 fd; / input: fd /
1749	__u32 flags; / input: flags /
1750	__u32 buf_len; / input/output: buf len /
1751	__aligned_u64 buf; / input/output:*
1752	* tp_name for tracepoint
1753	* symbol for kprobe
1754	* filename for uprobe
1755	*/
1756	__u32 prog_id; / output: prod_id /
1757	__u32 fd_type; / output: BPF_FD_TYPE_* /
1758	__u64 probe_offset; / output: probe_offset /
1759	__u64 probe_addr; / output: probe_addr /
1760	} task_fd_query;
1761
1762	struct { / struct used by BPF_LINK_CREATE command /
1763	union {
1764	__u32 prog_fd; / eBPF program to attach /
1765	__u32 map_fd; / struct_ops to attach /
1766	};
1767	union {
1768	__u32 target_fd; / target object to attach to or ... /
1769	__u32 target_ifindex; / target ifindex /
1770	};
1771	__u32 attach_type; / attach type /
1772	__u32 flags; / extra flags /
1773	union {
1774	__u32 target_btf_id; / btf_id of target to attach to /
1775	struct {
1776	__aligned_u64 iter_info; / extra bpf_iter_link_info /
1777	__u32 iter_info_len; / iter_info length /
1778	};
1779	struct {
1780	/ black box user-provided value passed through*
1781	* to BPF program at the execution time and
1782	* accessible through bpf_get_attach_cookie() BPF helper
1783	*/
1784	__u64 bpf_cookie;
1785	} perf_event;
1786	struct {
1787	__u32 flags;
1788	__u32 cnt;
1789	__aligned_u64 syms;
1790	__aligned_u64 addrs;
1791	__aligned_u64 cookies;
1792	} kprobe_multi;
1793	struct {
1794	/ this is overlaid with the target_btf_id above. /
1795	__u32 target_btf_id;
1796	/ black box user-provided value passed through*
1797	* to BPF program at the execution time and
1798	* accessible through bpf_get_attach_cookie() BPF helper
1799	*/
1800	__u64 cookie;
1801	} tracing;
1802	struct {
1803	__u32 pf;
1804	__u32 hooknum;
1805	__s32 priority;
1806	__u32 flags;
1807	} netfilter;
1808	struct {
1809	union {
1810	__u32 relative_fd;
1811	__u32 relative_id;
1812	};
1813	__u64 expected_revision;
1814	} tcx;
1815	struct {
1816	__aligned_u64 path;
1817	__aligned_u64 offsets;
1818	__aligned_u64 ref_ctr_offsets;
1819	__aligned_u64 cookies;
1820	__u32 cnt;
1821	__u32 flags;
1822	__u32 pid;
1823	} uprobe_multi;
1824	struct {
1825	union {
1826	__u32 relative_fd;
1827	__u32 relative_id;
1828	};
1829	__u64 expected_revision;
1830	} netkit;
1831	struct {
1832	union {
1833	__u32 relative_fd;
1834	__u32 relative_id;
1835	};
1836	__u64 expected_revision;
1837	} cgroup;
1838	};
1839	} link_create;
1840
1841	struct { / struct used by BPF_LINK_UPDATE command /
1842	__u32 link_fd; / link fd /
1843	union {
1844	/ new program fd to update link with /
1845	__u32 new_prog_fd;
1846	/ new struct_ops map fd to update link with /
1847	__u32 new_map_fd;
1848	};
1849	__u32 flags; / extra flags /
1850	union {
1851	/ expected link's program fd; is specified only if*
1852	* BPF_F_REPLACE flag is set in flags.
1853	*/
1854	__u32 old_prog_fd;
1855	/ expected link's map fd; is specified only*
1856	* if BPF_F_REPLACE flag is set.
1857	*/
1858	__u32 old_map_fd;
1859	};
1860	} link_update;
1861
1862	struct {
1863	__u32 link_fd;
1864	} link_detach;
1865
1866	struct { / struct used by BPF_ENABLE_STATS command /
1867	__u32 type;
1868	} enable_stats;
1869
1870	struct { / struct used by BPF_ITER_CREATE command /
1871	__u32 link_fd;
1872	__u32 flags;
1873	} iter_create;
1874
1875	struct { / struct used by BPF_PROG_BIND_MAP command /
1876	__u32 prog_fd;
1877	__u32 map_fd;
1878	__u32 flags; / extra flags /
1879	} prog_bind_map;
1880
1881	struct { / struct used by BPF_TOKEN_CREATE command /
1882	__u32 flags;
1883	__u32 bpffs_fd;
1884	} token_create;
1885
1886	struct {
1887	__aligned_u64 stream_buf;
1888	__u32 stream_buf_len;
1889	__u32 stream_id;
1890	__u32 prog_fd;
1891	} prog_stream_read;
1892
1893	} __attribute__((aligned(`8`)));
1894
1895	/ The description below is an attempt at providing documentation to eBPF*
1896	* developers about the multiple available eBPF helper functions. It can be
1897	* parsed and used to produce a manual page. The workflow is the following,
1898	* and requires the rst2man utility:
1899	*
1900	* $ ./scripts/bpf_doc.py \
1901	* --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
1902	* $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
1903	* $ man /tmp/bpf-helpers.7
1904	*
1905	* Note that in order to produce this external documentation, some RST
1906	* formatting is used in the descriptions to get "bold" and "italics" in
1907	* manual pages. Also note that the few trailing white spaces are
1908	* intentional, removing them would break paragraphs for rst2man.
1909	*
1910	* Start of BPF helper function descriptions:
1911	*
1912	* void bpf_map_lookup_elem(struct bpf_map map, const void *key)
1913	* Description
1914	* Perform a lookup in map for an entry associated to key.
1915	* Return
1916	* Map value associated to key, or NULL if no entry was
1917	* found.
1918	*
1919	* long bpf_map_update_elem(struct bpf_map map, const void key, const void *value, u64 flags)
1920	* Description
1921	* Add or update the value of the entry associated to key in
1922	* map with value. flags is one of:
1923	*
1924	* BPF_NOEXIST
1925	* The entry for key must not exist in the map.
1926	* BPF_EXIST
1927	* The entry for key must already exist in the map.
1928	* BPF_ANY
1929	* No condition on the existence of the entry for key.
1930	*
1931	* Flag value BPF_NOEXIST cannot be used for maps of types
1932	* BPF_MAP_TYPE_ARRAY or BPF_MAP_TYPE_PERCPU_ARRAY (all
1933	* elements always exist), the helper would return an error.
1934	* Return
1935	* 0 on success, or a negative error in case of failure.
1936	*
1937	* long bpf_map_delete_elem(struct bpf_map map, const void key)
1938	* Description
1939	* Delete entry with key from map.
1940	* Return
1941	* 0 on success, or a negative error in case of failure.
1942	*
1943	* long bpf_probe_read(void dst, u32 size, const void unsafe_ptr)
1944	* Description
1945	* For tracing programs, safely attempt to read size bytes from
1946	* kernel space address unsafe_ptr and store the data in dst.
1947	*
1948	* Generally, use bpf_probe_read_user\ () or
1949	* bpf_probe_read_kernel\ () instead.
1950	* Return
1951	* 0 on success, or a negative error in case of failure.
1952	*
1953	* u64 bpf_ktime_get_ns(void)
1954	* Description
1955	* Return the time elapsed since system boot, in nanoseconds.
1956	* Does not include time the system was suspended.
1957	* See: clock_gettime\ (CLOCK_MONOTONIC)
1958	* Return
1959	* Current ktime.
1960	*
1961	* long bpf_trace_printk(const char *fmt, u32 fmt_size, ...)
1962	* Description
1963	* This helper is a "printk()-like" facility for debugging. It
1964	* prints a message defined by format fmt (of size fmt_size)
1965	* to file \/sys/kernel/tracing/trace from TraceFS, if
1966	* available. It can take up to three additional u64
1967	* arguments (as an eBPF helpers, the total number of arguments is
1968	* limited to five).
1969	*
1970	* Each time the helper is called, it appends a line to the trace.
1971	* Lines are discarded while \/sys/kernel/tracing/trace is
1972	* open, use \/sys/kernel/tracing/trace_pipe to avoid this.
1973	* The format of the trace is customizable, and the exact output
1974	* one will get depends on the options set in
1975	* \/sys/kernel/tracing/trace_options (see also the
1976	* README file under the same directory). However, it usually
1977	* defaults to something like:
1978	*
1979	* ::
1980	*
1981	* telnet-470 [001] .N.. 419421.045894: 0x00000001: <formatted msg>
1982	*
1983	* In the above:
1984	*
1985	* * ``telnet`` is the name of the current task.
1986	* * ``470`` is the PID of the current task.
1987	* * ``001`` is the CPU number on which the task is
1988	* running.
1989	* * In ``.N..``, each character refers to a set of
1990	* options (whether irqs are enabled, scheduling
1991	* options, whether hard/softirqs are running, level of
1992	* preempt_disabled respectively). N means that
1993	* TIF_NEED_RESCHED and PREEMPT_NEED_RESCHED
1994	* are set.
1995	* * ``419421.045894`` is a timestamp.
1996	* * ``0x00000001`` is a fake value used by BPF for the
1997	* instruction pointer register.
1998	* * ``<formatted msg>`` is the message formatted with
1999	* fmt.
2000	*
2001	* The conversion specifiers supported by fmt are similar, but
2002	* more limited than for printk(). They are %d, %i,
2003	* %u, %x, %ld, %li, %lu, %lx, %lld,
2004	* %lli, %llu, %llx, %p, %s. No modifier (size
2005	* of field, padding with zeroes, etc.) is available, and the
2006	* helper will return -EINVAL (but print nothing) if it
2007	* encounters an unknown specifier.
2008	*
2009	* Also, note that bpf_trace_printk\ () is slow, and should
2010	* only be used for debugging purposes. For this reason, a notice
2011	* block (spanning several lines) is printed to kernel logs and
2012	* states that the helper should not be used "for production use"
2013	* the first time this helper is used (or more precisely, when
2014	* trace_printk\ () buffers are allocated). For passing values
2015	* to user space, perf events should be preferred.
2016	* Return
2017	* The number of bytes written to the buffer, or a negative error
2018	* in case of failure.
2019	*
2020	* u32 bpf_get_prandom_u32(void)
2021	* Description
2022	* Get a pseudo-random number.
2023	*
2024	* From a security point of view, this helper uses its own
2025	* pseudo-random internal state, and cannot be used to infer the
2026	* seed of other random functions in the kernel. However, it is
2027	* essential to note that the generator used by the helper is not
2028	* cryptographically secure.
2029	* Return
2030	* A random 32-bit unsigned value.
2031	*
2032	* u32 bpf_get_smp_processor_id(void)
2033	* Description
2034	* Get the SMP (symmetric multiprocessing) processor id. Note that
2035	* all programs run with migration disabled, which means that the
2036	* SMP processor id is stable during all the execution of the
2037	* program.
2038	* Return
2039	* The SMP id of the processor running the program.
2040	* Attributes
2041	* __bpf_fastcall
2042	*
2043	* long bpf_skb_store_bytes(struct sk_buff skb, u32 offset, const void from, u32 len, u64 flags)
2044	* Description
2045	* Store len bytes from address from into the packet
2046	* associated to skb, at offset. The flags are a combination
2047	* of the following values:
2048	*
2049	* BPF_F_RECOMPUTE_CSUM
2050	* Automatically update skb\ ->csum after storing the
2051	* bytes.
2052	* BPF_F_INVALIDATE_HASH
2053	* Set skb\ ->hash, skb\ ->swhash and skb\
2054	* ->l4hash to 0.
2055	*
2056	* A call to this helper is susceptible to change the underlying
2057	* packet buffer. Therefore, at load time, all checks on pointers
2058	* previously done by the verifier are invalidated and must be
2059	* performed again, if the helper is used in combination with
2060	* direct packet access.
2061	* Return
2062	* 0 on success, or a negative error in case of failure.
2063	*
2064	* long bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size)
2065	* Description
2066	* Recompute the layer 3 (e.g. IP) checksum for the packet
2067	* associated to skb. Computation is incremental, so the helper
2068	* must know the former value of the header field that was
2069	* modified (from), the new value of this field (to), and the
2070	* number of bytes (2 or 4) for this field, stored in size.
2071	* Alternatively, it is possible to store the difference between
2072	* the previous and the new values of the header field in to, by
2073	* setting from and size to 0. For both methods, offset
2074	* indicates the location of the IP checksum within the packet.
2075	*
2076	* This helper works in combination with bpf_csum_diff\ (),
2077	* which does not update the checksum in-place, but offers more
2078	* flexibility and can handle sizes larger than 2 or 4 for the
2079	* checksum to update.
2080	*
2081	* A call to this helper is susceptible to change the underlying
2082	* packet buffer. Therefore, at load time, all checks on pointers
2083	* previously done by the verifier are invalidated and must be
2084	* performed again, if the helper is used in combination with
2085	* direct packet access.
2086	* Return
2087	* 0 on success, or a negative error in case of failure.
2088	*
2089	* long bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags)
2090	* Description
2091	* Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the
2092	* packet associated to skb. Computation is incremental, so the
2093	* helper must know the former value of the header field that was
2094	* modified (from), the new value of this field (to), and the
2095	* number of bytes (2 or 4) for this field, stored on the lowest
2096	* four bits of flags. Alternatively, it is possible to store
2097	* the difference between the previous and the new values of the
2098	* header field in to, by setting from and the four lowest
2099	* bits of flags to 0. For both methods, offset indicates the
2100	* location of the IP checksum within the packet. In addition to
2101	* the size of the field, flags can be added (bitwise OR) actual
2102	* flags. With BPF_F_MARK_MANGLED_0, a null checksum is left
2103	* untouched (unless BPF_F_MARK_ENFORCE is added as well), and
2104	* for updates resulting in a null checksum the value is set to
2105	* CSUM_MANGLED_0 instead. Flag BPF_F_PSEUDO_HDR indicates
2106	* that the modified header field is part of the pseudo-header.
2107	* Flag BPF_F_IPV6 should be set for IPv6 packets.
2108	*
2109	* This helper works in combination with bpf_csum_diff\ (),
2110	* which does not update the checksum in-place, but offers more
2111	* flexibility and can handle sizes larger than 2 or 4 for the
2112	* checksum to update.
2113	*
2114	* A call to this helper is susceptible to change the underlying
2115	* packet buffer. Therefore, at load time, all checks on pointers
2116	* previously done by the verifier are invalidated and must be
2117	* performed again, if the helper is used in combination with
2118	* direct packet access.
2119	* Return
2120	* 0 on success, or a negative error in case of failure.
2121	*
2122	* long bpf_tail_call(void ctx, struct bpf_map prog_array_map, u32 index)
2123	* Description
2124	* This special helper is used to trigger a "tail call", or in
2125	* other words, to jump into another eBPF program. The same stack
2126	* frame is used (but values on stack and in registers for the
2127	* caller are not accessible to the callee). This mechanism allows
2128	* for program chaining, either for raising the maximum number of
2129	* available eBPF instructions, or to execute given programs in
2130	* conditional blocks. For security reasons, there is an upper
2131	* limit to the number of successive tail calls that can be
2132	* performed.
2133	*
2134	* Upon call of this helper, the program attempts to jump into a
2135	* program referenced at index index in prog_array_map, a
2136	* special map of type BPF_MAP_TYPE_PROG_ARRAY, and passes
2137	* ctx, a pointer to the context.
2138	*
2139	* If the call succeeds, the kernel immediately runs the first
2140	* instruction of the new program. This is not a function call,
2141	* and it never returns to the previous program. If the call
2142	* fails, then the helper has no effect, and the caller continues
2143	* to run its subsequent instructions. A call can fail if the
2144	* destination program for the jump does not exist (i.e. index
2145	* is superior to the number of entries in prog_array_map), or
2146	* if the maximum number of tail calls has been reached for this
2147	* chain of programs. This limit is defined in the kernel by the
2148	* macro MAX_TAIL_CALL_CNT (not accessible to user space),
2149	* which is currently set to 33.
2150	* Return
2151	* 0 on success, or a negative error in case of failure.
2152	*
2153	* long bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags)
2154	* Description
2155	* Clone and redirect the packet associated to skb to another
2156	* net device of index ifindex. Both ingress and egress
2157	* interfaces can be used for redirection. The BPF_F_INGRESS
2158	* value in flags is used to make the distinction (ingress path
2159	* is selected if the flag is present, egress path otherwise).
2160	* This is the only flag supported for now.
2161	*
2162	* In comparison with bpf_redirect\ () helper,
2163	* bpf_clone_redirect\ () has the associated cost of
2164	* duplicating the packet buffer, but this can be executed out of
2165	* the eBPF program. Conversely, bpf_redirect\ () is more
2166	* efficient, but it is handled through an action code where the
2167	* redirection happens only after the eBPF program has returned.
2168	*
2169	* A call to this helper is susceptible to change the underlying
2170	* packet buffer. Therefore, at load time, all checks on pointers
2171	* previously done by the verifier are invalidated and must be
2172	* performed again, if the helper is used in combination with
2173	* direct packet access.
2174	* Return
2175	* 0 on success, or a negative error in case of failure. Positive
2176	* error indicates a potential drop or congestion in the target
2177	* device. The particular positive error codes are not defined.
2178	*
2179	* u64 bpf_get_current_pid_tgid(void)
2180	* Description
2181	* Get the current pid and tgid.
2182	* Return
2183	* A 64-bit integer containing the current tgid and pid, and
2184	* created as such:
2185	* current_task\ ->tgid << 32 \\|
2186	* current_task\ ->pid.
2187	*
2188	* u64 bpf_get_current_uid_gid(void)
2189	* Description
2190	* Get the current uid and gid.
2191	* Return
2192	* A 64-bit integer containing the current GID and UID, and
2193	* created as such: current_gid << 32 \\| current_uid.
2194	*
2195	* long bpf_get_current_comm(void *buf, u32 size_of_buf)
2196	* Description
2197	* Copy the comm attribute of the current task into buf of
2198	* size_of_buf. The comm attribute contains the name of
2199	* the executable (excluding the path) for the current task. The
2200	* size_of_buf must be strictly positive. On success, the
2201	* helper makes sure that the buf is NUL-terminated. On failure,
2202	* it is filled with zeroes.
2203	* Return
2204	* 0 on success, or a negative error in case of failure.
2205	*
2206	* u32 bpf_get_cgroup_classid(struct sk_buff *skb)
2207	* Description
2208	* Retrieve the classid for the current task, i.e. for the net_cls
2209	* cgroup to which skb belongs.
2210	*
2211	* This helper can be used on TC egress path, but not on ingress.
2212	*
2213	* The net_cls cgroup provides an interface to tag network packets
2214	* based on a user-provided identifier for all traffic coming from
2215	* the tasks belonging to the related cgroup. See also the related
2216	* kernel documentation, available from the Linux sources in file
2217	* Documentation/admin-guide/cgroup-v1/net_cls.rst.
2218	*
2219	* The Linux kernel has two versions for cgroups: there are
2220	* cgroups v1 and cgroups v2. Both are available to users, who can
2221	* use a mixture of them, but note that the net_cls cgroup is for
2222	* cgroup v1 only. This makes it incompatible with BPF programs
2223	* run on cgroups, which is a cgroup-v2-only feature (a socket can
2224	* only hold data for one version of cgroups at a time).
2225	*
2226	* This helper is only available is the kernel was compiled with
2227	* the CONFIG_CGROUP_NET_CLASSID configuration option set to
2228	* "y" or to "m".
2229	* Return
2230	* The classid, or 0 for the default unconfigured classid.
2231	*
2232	* long bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
2233	* Description
2234	* Push a vlan_tci (VLAN tag control information) of protocol
2235	* vlan_proto to the packet associated to skb, then update
2236	* the checksum. Note that if vlan_proto is different from
2237	* ETH_P_8021Q and ETH_P_8021AD, it is considered to
2238	* be ETH_P_8021Q.
2239	*
2240	* A call to this helper is susceptible to change the underlying
2241	* packet buffer. Therefore, at load time, all checks on pointers
2242	* previously done by the verifier are invalidated and must be
2243	* performed again, if the helper is used in combination with
2244	* direct packet access.
2245	* Return
2246	* 0 on success, or a negative error in case of failure.
2247	*
2248	* long bpf_skb_vlan_pop(struct sk_buff *skb)
2249	* Description
2250	* Pop a VLAN header from the packet associated to skb.
2251	*
2252	* A call to this helper is susceptible to change the underlying
2253	* packet buffer. Therefore, at load time, all checks on pointers
2254	* previously done by the verifier are invalidated and must be
2255	* performed again, if the helper is used in combination with
2256	* direct packet access.
2257	* Return
2258	* 0 on success, or a negative error in case of failure.
2259	*
2260	* long bpf_skb_get_tunnel_key(struct sk_buff skb, struct bpf_tunnel_key key, u32 size, u64 flags)
2261	* Description
2262	* Get tunnel metadata. This helper takes a pointer key to an
2263	* empty struct bpf_tunnel_key of size, that will be
2264	* filled with tunnel metadata for the packet associated to skb.
2265	* The flags can be set to BPF_F_TUNINFO_IPV6, which
2266	* indicates that the tunnel is based on IPv6 protocol instead of
2267	* IPv4.
2268	*
2269	* The struct bpf_tunnel_key is an object that generalizes the
2270	* principal parameters used by various tunneling protocols into a
2271	* single struct. This way, it can be used to easily make a
2272	* decision based on the contents of the encapsulation header,
2273	* "summarized" in this struct. In particular, it holds the IP
2274	* address of the remote end (IPv4 or IPv6, depending on the case)
2275	* in key\ ->remote_ipv4 or key\ ->remote_ipv6. Also,
2276	* this struct exposes the key\ ->tunnel_id, which is
2277	* generally mapped to a VNI (Virtual Network Identifier), making
2278	* it programmable together with the bpf_skb_set_tunnel_key\
2279	* () helper.
2280	*
2281	* Let's imagine that the following code is part of a program
2282	* attached to the TC ingress interface, on one end of a GRE
2283	* tunnel, and is supposed to filter out all messages coming from
2284	* remote ends with IPv4 address other than 10.0.0.1:
2285	*
2286	* ::
2287	*
2288	* int ret;
2289	* struct bpf_tunnel_key key = {};
2290	*
2291	* ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
2292	* if (ret < 0)
2293	* return TC_ACT_SHOT; // drop packet
2294	*
2295	* if (key.remote_ipv4 != 0x0a000001)
2296	* return TC_ACT_SHOT; // drop packet
2297	*
2298	* return TC_ACT_OK; // accept packet
2299	*
2300	* This interface can also be used with all encapsulation devices
2301	* that can operate in "collect metadata" mode: instead of having
2302	* one network device per specific configuration, the "collect
2303	* metadata" mode only requires a single device where the
2304	* configuration can be extracted from this helper.
2305	*
2306	* This can be used together with various tunnels such as VXLan,
2307	* Geneve, GRE or IP in IP (IPIP).
2308	* Return
2309	* 0 on success, or a negative error in case of failure.
2310	*
2311	* long bpf_skb_set_tunnel_key(struct sk_buff skb, struct bpf_tunnel_key key, u32 size, u64 flags)
2312	* Description
2313	* Populate tunnel metadata for packet associated to skb. The
2314	* tunnel metadata is set to the contents of key, of size. The
2315	* flags can be set to a combination of the following values:
2316	*
2317	* BPF_F_TUNINFO_IPV6
2318	* Indicate that the tunnel is based on IPv6 protocol
2319	* instead of IPv4.
2320	* BPF_F_ZERO_CSUM_TX
2321	* For IPv4 packets, add a flag to tunnel metadata
2322	* indicating that checksum computation should be skipped
2323	* and checksum set to zeroes.
2324	* BPF_F_DONT_FRAGMENT
2325	* Add a flag to tunnel metadata indicating that the
2326	* packet should not be fragmented.
2327	* BPF_F_SEQ_NUMBER
2328	* Add a flag to tunnel metadata indicating that a
2329	* sequence number should be added to tunnel header before
2330	* sending the packet. This flag was added for GRE
2331	* encapsulation, but might be used with other protocols
2332	* as well in the future.
2333	* BPF_F_NO_TUNNEL_KEY
2334	* Add a flag to tunnel metadata indicating that no tunnel
2335	* key should be set in the resulting tunnel header.
2336	*
2337	* Here is a typical usage on the transmit path:
2338	*
2339	* ::
2340	*
2341	* struct bpf_tunnel_key key;
2342	* populate key ...
2343	* bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
2344	* bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);
2345	*
2346	* See also the description of the bpf_skb_get_tunnel_key\ ()
2347	* helper for additional information.
2348	* Return
2349	* 0 on success, or a negative error in case of failure.
2350	*
2351	* u64 bpf_perf_event_read(struct bpf_map *map, u64 flags)
2352	* Description
2353	* Read the value of a perf event counter. This helper relies on a
2354	* map of type BPF_MAP_TYPE_PERF_EVENT_ARRAY. The nature of
2355	* the perf event counter is selected when map is updated with
2356	* perf event file descriptors. The map is an array whose size
2357	* is the number of available CPUs, and each cell contains a value
2358	* relative to one CPU. The value to retrieve is indicated by
2359	* flags, that contains the index of the CPU to look up, masked
2360	* with BPF_F_INDEX_MASK. Alternatively, flags can be set to
2361	* BPF_F_CURRENT_CPU to indicate that the value for the
2362	* current CPU should be retrieved.
2363	*
2364	* Note that before Linux 4.13, only hardware perf event can be
2365	* retrieved.
2366	*
2367	* Also, be aware that the newer helper
2368	* bpf_perf_event_read_value\ () is recommended over
2369	* bpf_perf_event_read\ () in general. The latter has some ABI
2370	* quirks where error and counter value are used as a return code
2371	* (which is wrong to do since ranges may overlap). This issue is
2372	* fixed with bpf_perf_event_read_value\ (), which at the same
2373	* time provides more features over the bpf_perf_event_read\
2374	* () interface. Please refer to the description of
2375	* bpf_perf_event_read_value\ () for details.
2376	* Return
2377	* The value of the perf event counter read from the map, or a
2378	* negative error code in case of failure.
2379	*
2380	* long bpf_redirect(u32 ifindex, u64 flags)
2381	* Description
2382	* Redirect the packet to another net device of index ifindex.
2383	* This helper is somewhat similar to bpf_clone_redirect\
2384	* (), except that the packet is not cloned, which provides
2385	* increased performance.
2386	*
2387	* Except for XDP, both ingress and egress interfaces can be used
2388	* for redirection. The BPF_F_INGRESS value in flags is used
2389	* to make the distinction (ingress path is selected if the flag
2390	* is present, egress path otherwise). Currently, XDP only
2391	* supports redirection to the egress interface, and accepts no
2392	* flag at all.
2393	*
2394	* The same effect can also be attained with the more generic
2395	* bpf_redirect_map\ (), which uses a BPF map to store the
2396	* redirect target instead of providing it directly to the helper.
2397	* Return
2398	* For XDP, the helper returns XDP_REDIRECT on success or
2399	* XDP_ABORTED on error. For other program types, the values
2400	* are TC_ACT_REDIRECT on success or TC_ACT_SHOT on
2401	* error.
2402	*
2403	* u32 bpf_get_route_realm(struct sk_buff *skb)
2404	* Description
2405	* Retrieve the realm or the route, that is to say the
2406	* tclassid field of the destination for the skb. The
2407	* identifier retrieved is a user-provided tag, similar to the
2408	* one used with the net_cls cgroup (see description for
2409	* bpf_get_cgroup_classid\ () helper), but here this tag is
2410	* held by a route (a destination entry), not by a task.
2411	*
2412	* Retrieving this identifier works with the clsact TC egress hook
2413	* (see also tc-bpf(8)), or alternatively on conventional
2414	* classful egress qdiscs, but not on TC ingress path. In case of
2415	* clsact TC egress hook, this has the advantage that, internally,
2416	* the destination entry has not been dropped yet in the transmit
2417	* path. Therefore, the destination entry does not need to be
2418	* artificially held via netif_keep_dst\ () for a classful
2419	* qdisc until the skb is freed.
2420	*
2421	* This helper is available only if the kernel was compiled with
2422	* CONFIG_IP_ROUTE_CLASSID configuration option.
2423	* Return
2424	* The realm of the route for the packet associated to skb, or 0
2425	* if none was found.
2426	*
2427	* long bpf_perf_event_output(void ctx, struct bpf_map map, u64 flags, void *data, u64 size)
2428	* Description
2429	* Write raw data blob into a special BPF perf event held by
2430	* map of type BPF_MAP_TYPE_PERF_EVENT_ARRAY. This perf
2431	* event must have the following attributes: PERF_SAMPLE_RAW
2432	* as sample_type, PERF_TYPE_SOFTWARE as type, and
2433	* PERF_COUNT_SW_BPF_OUTPUT as config.
2434	*
2435	* The flags are used to indicate the index in map for which
2436	* the value must be put, masked with BPF_F_INDEX_MASK.
2437	* Alternatively, flags can be set to BPF_F_CURRENT_CPU
2438	* to indicate that the index of the current CPU core should be
2439	* used.
2440	*
2441	* The value to write, of size, is passed through eBPF stack and
2442	* pointed by data.
2443	*
2444	* The context of the program ctx needs also be passed to the
2445	* helper.
2446	*
2447	* On user space, a program willing to read the values needs to
2448	* call perf_event_open\ () on the perf event (either for
2449	* one or for all CPUs) and to store the file descriptor into the
2450	* map. This must be done before the eBPF program can send data
2451	* into it. An example is available in file
2452	* samples/bpf/trace_output_user.c in the Linux kernel source
2453	* tree (the eBPF program counterpart is in
2454	* samples/bpf/trace_output.bpf.c).
2455	*
2456	* bpf_perf_event_output\ () achieves better performance
2457	* than bpf_trace_printk\ () for sharing data with user
2458	* space, and is much better suitable for streaming data from eBPF
2459	* programs.
2460	*
2461	* Note that this helper is not restricted to tracing use cases
2462	* and can be used with programs attached to TC or XDP as well,
2463	* where it allows for passing data to user space listeners. Data
2464	* can be:
2465	*
2466	* * Only custom structs,
2467	* * Only the packet payload, or
2468	* * A combination of both.
2469	* Return
2470	* 0 on success, or a negative error in case of failure.
2471	*
2472	* long bpf_skb_load_bytes(const void skb, u32 offset, void to, u32 len)
2473	* Description
2474	* This helper was provided as an easy way to load data from a
2475	* packet. It can be used to load len bytes from offset from
2476	* the packet associated to skb, into the buffer pointed by
2477	* to.
2478	*
2479	* Since Linux 4.7, usage of this helper has mostly been replaced
2480	* by "direct packet access", enabling packet data to be
2481	* manipulated with skb\ ->data and skb\ ->data_end
2482	* pointing respectively to the first byte of packet data and to
2483	* the byte after the last byte of packet data. However, it
2484	* remains useful if one wishes to read large quantities of data
2485	* at once from a packet into the eBPF stack.
2486	* Return
2487	* 0 on success, or a negative error in case of failure.
2488	*
2489	* long bpf_get_stackid(void ctx, struct bpf_map map, u64 flags)
2490	* Description
2491	* Walk a user or a kernel stack and return its id. To achieve
2492	* this, the helper needs ctx, which is a pointer to the context
2493	* on which the tracing program is executed, and a pointer to a
2494	* map of type BPF_MAP_TYPE_STACK_TRACE.
2495	*
2496	* The last argument, flags, holds the number of stack frames to
2497	* skip (from 0 to 255), masked with
2498	* BPF_F_SKIP_FIELD_MASK. The next bits can be used to set
2499	* a combination of the following flags:
2500	*
2501	* BPF_F_USER_STACK
2502	* Collect a user space stack instead of a kernel stack.
2503	* BPF_F_FAST_STACK_CMP
2504	* Compare stacks by hash only.
2505	* BPF_F_REUSE_STACKID
2506	* If two different stacks hash into the same stackid,
2507	* discard the old one.
2508	*
2509	* The stack id retrieved is a 32 bit long integer handle which
2510	* can be further combined with other data (including other stack
2511	* ids) and used as a key into maps. This can be useful for
2512	* generating a variety of graphs (such as flame graphs or off-cpu
2513	* graphs).
2514	*
2515	* For walking a stack, this helper is an improvement over
2516	* bpf_probe_read\ (), which can be used with unrolled loops
2517	* but is not efficient and consumes a lot of eBPF instructions.
2518	* Instead, bpf_get_stackid\ () can collect up to
2519	* PERF_MAX_STACK_DEPTH both kernel and user frames. Note that
2520	* this limit can be controlled with the sysctl program, and
2521	* that it should be manually increased in order to profile long
2522	* user stacks (such as stacks for Java programs). To do so, use:
2523	*
2524	* ::
2525	*
2526	* # sysctl kernel.perf_event_max_stack=<new value>
2527	* Return
2528	* The positive or null stack id on success, or a negative error
2529	* in case of failure.
2530	*
2531	* s64 bpf_csum_diff(__be32 from, u32 from_size, __be32 to, u32 to_size, __wsum seed)
2532	* Description
2533	* Compute a checksum difference, from the raw buffer pointed by
2534	* from, of length from_size (that must be a multiple of 4),
2535	* towards the raw buffer pointed by to, of size to_size
2536	* (same remark). An optional seed can be added to the value
2537	* (this can be cascaded, the seed may come from a previous call
2538	* to the helper).
2539	*
2540	* This is flexible enough to be used in several ways:
2541	*
2542	* * With from_size == 0, to_size > 0 and seed set to
2543	* checksum, it can be used when pushing new data.
2544	* * With from_size > 0, to_size == 0 and seed set to
2545	* checksum, it can be used when removing data from a packet.
2546	* * With from_size > 0, to_size > 0 and seed set to 0, it
2547	* can be used to compute a diff. Note that from_size and
2548	* to_size do not need to be equal.
2549	*
2550	* This helper can be used in combination with
2551	* bpf_l3_csum_replace\ () and bpf_l4_csum_replace\ (), to
2552	* which one can feed in the difference computed with
2553	* bpf_csum_diff\ ().
2554	* Return
2555	* The checksum result, or a negative error code in case of
2556	* failure.
2557	*
2558	* long bpf_skb_get_tunnel_opt(struct sk_buff skb, void opt, u32 size)
2559	* Description
2560	* Retrieve tunnel options metadata for the packet associated to
2561	* skb, and store the raw tunnel option data to the buffer opt
2562	* of size.
2563	*
2564	* This helper can be used with encapsulation devices that can
2565	* operate in "collect metadata" mode (please refer to the related
2566	* note in the description of bpf_skb_get_tunnel_key\ () for
2567	* more details). A particular example where this can be used is
2568	* in combination with the Geneve encapsulation protocol, where it
2569	* allows for pushing (with bpf_skb_get_tunnel_opt\ () helper)
2570	* and retrieving arbitrary TLVs (Type-Length-Value headers) from
2571	* the eBPF program. This allows for full customization of these
2572	* headers.
2573	* Return
2574	* The size of the option data retrieved.
2575	*
2576	* long bpf_skb_set_tunnel_opt(struct sk_buff skb, void opt, u32 size)
2577	* Description
2578	* Set tunnel options metadata for the packet associated to skb
2579	* to the option data contained in the raw buffer opt of size.
2580	*
2581	* See also the description of the bpf_skb_get_tunnel_opt\ ()
2582	* helper for additional information.
2583	* Return
2584	* 0 on success, or a negative error in case of failure.
2585	*
2586	* long bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags)
2587	* Description
2588	* Change the protocol of the skb to proto. Currently
2589	* supported are transition from IPv4 to IPv6, and from IPv6 to
2590	* IPv4. The helper takes care of the groundwork for the
2591	* transition, including resizing the socket buffer. The eBPF
2592	* program is expected to fill the new headers, if any, via
2593	* skb_store_bytes\ () and to recompute the checksums with
2594	* bpf_l3_csum_replace\ () and bpf_l4_csum_replace\
2595	* (). The main case for this helper is to perform NAT64
2596	* operations out of an eBPF program.
2597	*
2598	* Internally, the GSO type is marked as dodgy so that headers are
2599	* checked and segments are recalculated by the GSO/GRO engine.
2600	* The size for GSO target is adapted as well.
2601	*
2602	* All values for flags are reserved for future usage, and must
2603	* be left at zero.
2604	*
2605	* A call to this helper is susceptible to change the underlying
2606	* packet buffer. Therefore, at load time, all checks on pointers
2607	* previously done by the verifier are invalidated and must be
2608	* performed again, if the helper is used in combination with
2609	* direct packet access.
2610	* Return
2611	* 0 on success, or a negative error in case of failure.
2612	*
2613	* long bpf_skb_change_type(struct sk_buff *skb, u32 type)
2614	* Description
2615	* Change the packet type for the packet associated to skb. This
2616	* comes down to setting skb\ ->pkt_type to type, except
2617	* the eBPF program does not have a write access to skb\
2618	* ->pkt_type beside this helper. Using a helper here allows
2619	* for graceful handling of errors.
2620	*
2621	* The major use case is to change incoming skbs to
2622	* PACKET_HOST in a programmatic way instead of having to
2623	* recirculate via redirect\ (..., BPF_F_INGRESS), for
2624	* example.
2625	*
2626	* Note that type only allows certain values. At this time, they
2627	* are:
2628	*
2629	* PACKET_HOST
2630	* Packet is for us.
2631	* PACKET_BROADCAST
2632	* Send packet to all.
2633	* PACKET_MULTICAST
2634	* Send packet to group.
2635	* PACKET_OTHERHOST
2636	* Send packet to someone else.
2637	* Return
2638	* 0 on success, or a negative error in case of failure.
2639	*
2640	* long bpf_skb_under_cgroup(struct sk_buff skb, struct bpf_map map, u32 index)
2641	* Description
2642	* Check whether skb is a descendant of the cgroup2 held by
2643	* map of type BPF_MAP_TYPE_CGROUP_ARRAY, at index.
2644	* Return
2645	* The return value depends on the result of the test, and can be:
2646	*
2647	* * 0, if the skb failed the cgroup2 descendant test.
2648	* * 1, if the skb succeeded the cgroup2 descendant test.
2649	* * A negative error code, if an error occurred.
2650	*
2651	* u32 bpf_get_hash_recalc(struct sk_buff *skb)
2652	* Description
2653	* Retrieve the hash of the packet, skb\ ->hash. If it is
2654	* not set, in particular if the hash was cleared due to mangling,
2655	* recompute this hash. Later accesses to the hash can be done
2656	* directly with skb\ ->hash.
2657	*
2658	* Calling bpf_set_hash_invalid\ (), changing a packet
2659	* prototype with bpf_skb_change_proto\ (), or calling
2660	* bpf_skb_store_bytes\ () with the
2661	* BPF_F_INVALIDATE_HASH are actions susceptible to clear
2662	* the hash and to trigger a new computation for the next call to
2663	* bpf_get_hash_recalc\ ().
2664	* Return
2665	* The 32-bit hash.
2666	*
2667	* u64 bpf_get_current_task(void)
2668	* Description
2669	* Get the current task.
2670	* Return
2671	* A pointer to the current task struct.
2672	*
2673	* long bpf_probe_write_user(void dst, const void src, u32 len)
2674	* Description
2675	* Attempt in a safe way to write len bytes from the buffer
2676	* src to dst in memory. It only works for threads that are in
2677	* user context, and dst must be a valid user space address.
2678	*
2679	* This helper should not be used to implement any kind of
2680	* security mechanism because of TOC-TOU attacks, but rather to
2681	* debug, divert, and manipulate execution of semi-cooperative
2682	* processes.
2683	*
2684	* Keep in mind that this feature is meant for experiments, and it
2685	* has a risk of crashing the system and running programs.
2686	* Therefore, when an eBPF program using this helper is attached,
2687	* a warning including PID and process name is printed to kernel
2688	* logs.
2689	* Return
2690	* 0 on success, or a negative error in case of failure.
2691	*
2692	* long bpf_current_task_under_cgroup(struct bpf_map *map, u32 index)
2693	* Description
2694	* Check whether the probe is being run is the context of a given
2695	* subset of the cgroup2 hierarchy. The cgroup2 to test is held by
2696	* map of type BPF_MAP_TYPE_CGROUP_ARRAY, at index.
2697	* Return
2698	* The return value depends on the result of the test, and can be:
2699	*
2700	* * 1, if current task belongs to the cgroup2.
2701	* * 0, if current task does not belong to the cgroup2.
2702	* * A negative error code, if an error occurred.
2703	*
2704	* long bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags)
2705	* Description
2706	* Resize (trim or grow) the packet associated to skb to the
2707	* new len. The flags are reserved for future usage, and must
2708	* be left at zero.
2709	*
2710	* The basic idea is that the helper performs the needed work to
2711	* change the size of the packet, then the eBPF program rewrites
2712	* the rest via helpers like bpf_skb_store_bytes\ (),
2713	* bpf_l3_csum_replace\ (), bpf_l3_csum_replace\ ()
2714	* and others. This helper is a slow path utility intended for
2715	* replies with control messages. And because it is targeted for
2716	* slow path, the helper itself can afford to be slow: it
2717	* implicitly linearizes, unclones and drops offloads from the
2718	* skb.
2719	*
2720	* A call to this helper is susceptible to change the underlying
2721	* packet buffer. Therefore, at load time, all checks on pointers
2722	* previously done by the verifier are invalidated and must be
2723	* performed again, if the helper is used in combination with
2724	* direct packet access.
2725	* Return
2726	* 0 on success, or a negative error in case of failure.
2727	*
2728	* long bpf_skb_pull_data(struct sk_buff *skb, u32 len)
2729	* Description
2730	* Pull in non-linear data in case the skb is non-linear and not
2731	* all of len are part of the linear section. Make len bytes
2732	* from skb readable and writable. If a zero value is passed for
2733	* len, then all bytes in the linear part of skb will be made
2734	* readable and writable.
2735	*
2736	* This helper is only needed for reading and writing with direct
2737	* packet access.
2738	*
2739	* For direct packet access, testing that offsets to access
2740	* are within packet boundaries (test on skb\ ->data_end) is
2741	* susceptible to fail if offsets are invalid, or if the requested
2742	* data is in non-linear parts of the skb. On failure the
2743	* program can just bail out, or in the case of a non-linear
2744	* buffer, use a helper to make the data available. The
2745	* bpf_skb_load_bytes\ () helper is a first solution to access
2746	* the data. Another one consists in using bpf_skb_pull_data
2747	* to pull in once the non-linear parts, then retesting and
2748	* eventually access the data.
2749	*
2750	* At the same time, this also makes sure the skb is uncloned,
2751	* which is a necessary condition for direct write. As this needs
2752	* to be an invariant for the write part only, the verifier
2753	* detects writes and adds a prologue that is calling
2754	* bpf_skb_pull_data() to effectively unclone the skb from
2755	* the very beginning in case it is indeed cloned.
2756	*
2757	* A call to this helper is susceptible to change the underlying
2758	* packet buffer. Therefore, at load time, all checks on pointers
2759	* previously done by the verifier are invalidated and must be
2760	* performed again, if the helper is used in combination with
2761	* direct packet access.
2762	* Return
2763	* 0 on success, or a negative error in case of failure.
2764	*
2765	* s64 bpf_csum_update(struct sk_buff *skb, __wsum csum)
2766	* Description
2767	* Add the checksum csum into skb\ ->csum in case the
2768	* driver has supplied a checksum for the entire packet into that
2769	* field. Return an error otherwise. This helper is intended to be
2770	* used in combination with bpf_csum_diff\ (), in particular
2771	* when the checksum needs to be updated after data has been
2772	* written into the packet through direct packet access.
2773	* Return
2774	* The checksum on success, or a negative error code in case of
2775	* failure.
2776	*
2777	* void bpf_set_hash_invalid(struct sk_buff *skb)
2778	* Description
2779	* Invalidate the current skb\ ->hash. It can be used after
2780	* mangling on headers through direct packet access, in order to
2781	* indicate that the hash is outdated and to trigger a
2782	* recalculation the next time the kernel tries to access this
2783	* hash or when the bpf_get_hash_recalc\ () helper is called.
2784	* Return
2785	* void.
2786	*
2787	* long bpf_get_numa_node_id(void)
2788	* Description
2789	* Return the id of the current NUMA node. The primary use case
2790	* for this helper is the selection of sockets for the local NUMA
2791	* node, when the program is attached to sockets using the
2792	* SO_ATTACH_REUSEPORT_EBPF option (see also socket(7)),
2793	* but the helper is also available to other eBPF program types,
2794	* similarly to bpf_get_smp_processor_id\ ().
2795	* Return
2796	* The id of current NUMA node.
2797	*
2798	* long bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags)
2799	* Description
2800	* Grows headroom of packet associated to skb and adjusts the
2801	* offset of the MAC header accordingly, adding len bytes of
2802	* space. It automatically extends and reallocates memory as
2803	* required.
2804	*
2805	* This helper can be used on a layer 3 skb to push a MAC header
2806	* for redirection into a layer 2 device.
2807	*
2808	* All values for flags are reserved for future usage, and must
2809	* be left at zero.
2810	*
2811	* A call to this helper is susceptible to change the underlying
2812	* packet buffer. Therefore, at load time, all checks on pointers
2813	* previously done by the verifier are invalidated and must be
2814	* performed again, if the helper is used in combination with
2815	* direct packet access.
2816	* Return
2817	* 0 on success, or a negative error in case of failure.
2818	*
2819	* long bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta)
2820	* Description
2821	* Adjust (move) xdp_md\ ->data by delta bytes. Note that
2822	* it is possible to use a negative value for delta. This helper
2823	* can be used to prepare the packet for pushing or popping
2824	* headers.
2825	*
2826	* A call to this helper is susceptible to change the underlying
2827	* packet buffer. Therefore, at load time, all checks on pointers
2828	* previously done by the verifier are invalidated and must be
2829	* performed again, if the helper is used in combination with
2830	* direct packet access.
2831	* Return
2832	* 0 on success, or a negative error in case of failure.
2833	*
2834	* long bpf_probe_read_str(void dst, u32 size, const void unsafe_ptr)
2835	* Description
2836	* Copy a NUL terminated string from an unsafe kernel address
2837	* unsafe_ptr to dst. See bpf_probe_read_kernel_str\ () for
2838	* more details.
2839	*
2840	* Generally, use bpf_probe_read_user_str\ () or
2841	* bpf_probe_read_kernel_str\ () instead.
2842	* Return
2843	* On success, the strictly positive length of the string,
2844	* including the trailing NUL character. On error, a negative
2845	* value.
2846	*
2847	* u64 bpf_get_socket_cookie(struct sk_buff *skb)
2848	* Description
2849	* If the struct sk_buff pointed by skb has a known socket,
2850	* retrieve the cookie (generated by the kernel) of this socket.
2851	* If no cookie has been set yet, generate a new cookie. Once
2852	* generated, the socket cookie remains stable for the life of the
2853	* socket. This helper can be useful for monitoring per socket
2854	* networking traffic statistics as it provides a global socket
2855	* identifier that can be assumed unique.
2856	* Return
2857	* A 8-byte long unique number on success, or 0 if the socket
2858	* field is missing inside skb.
2859	*
2860	* u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
2861	* Description
2862	* Equivalent to bpf_get_socket_cookie() helper that accepts
2863	* skb, but gets socket from struct bpf_sock_addr context.
2864	* Return
2865	* A 8-byte long unique number.
2866	*
2867	* u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx)
2868	* Description
2869	* Equivalent to bpf_get_socket_cookie\ () helper that accepts
2870	* skb, but gets socket from struct bpf_sock_ops context.
2871	* Return
2872	* A 8-byte long unique number.
2873	*
2874	* u64 bpf_get_socket_cookie(struct sock *sk)
2875	* Description
2876	* Equivalent to bpf_get_socket_cookie\ () helper that accepts
2877	* sk, but gets socket from a BTF struct sock. This helper
2878	* also works for sleepable programs.
2879	* Return
2880	* A 8-byte long unique number or 0 if sk is NULL.
2881	*
2882	* u32 bpf_get_socket_uid(struct sk_buff *skb)
2883	* Description
2884	* Get the owner UID of the socked associated to skb.
2885	* Return
2886	* The owner UID of the socket associated to skb. If the socket
2887	* is NULL, or if it is not a full socket (i.e. if it is a
2888	* time-wait or a request socket instead), overflowuid value
2889	* is returned (note that overflowuid might also be the actual
2890	* UID value for the socket).
2891	*
2892	* long bpf_set_hash(struct sk_buff *skb, u32 hash)
2893	* Description
2894	* Set the full hash for skb (set the field skb\ ->hash)
2895	* to value hash.
2896	* Return
2897	* 0
2898	*
2899	* long bpf_setsockopt(void bpf_socket, int level, int optname, void optval, int optlen)
2900	* Description
2901	* Emulate a call to setsockopt() on the socket associated to
2902	* bpf_socket, which must be a full socket. The level at
2903	* which the option resides and the name optname of the option
2904	* must be specified, see setsockopt(2) for more information.
2905	* The option value of length optlen is pointed by optval.
2906	*
2907	* bpf_socket should be one of the following:
2908	*
2909	* * struct bpf_sock_ops for BPF_PROG_TYPE_SOCK_OPS.
2910	* * struct bpf_sock_addr for BPF_CGROUP_INET4_CONNECT,
2911	* BPF_CGROUP_INET6_CONNECT and BPF_CGROUP_UNIX_CONNECT.
2912	*
2913	* This helper actually implements a subset of setsockopt().
2914	* It supports the following level\ s:
2915	*
2916	* * SOL_SOCKET, which supports the following optname\ s:
2917	* SO_RCVBUF, SO_SNDBUF, SO_MAX_PACING_RATE,
2918	* SO_PRIORITY, SO_RCVLOWAT, SO_MARK,
2919	* SO_BINDTODEVICE, SO_KEEPALIVE, SO_REUSEADDR,
2920	* SO_REUSEPORT, SO_BINDTOIFINDEX, SO_TXREHASH.
2921	* * IPPROTO_TCP, which supports the following optname\ s:
2922	* TCP_CONGESTION, TCP_BPF_IW,
2923	* TCP_BPF_SNDCWND_CLAMP, TCP_SAVE_SYN,
2924	* TCP_KEEPIDLE, TCP_KEEPINTVL, TCP_KEEPCNT,
2925	* TCP_SYNCNT, TCP_USER_TIMEOUT, TCP_NOTSENT_LOWAT,
2926	* TCP_NODELAY, TCP_MAXSEG, TCP_WINDOW_CLAMP,
2927	* TCP_THIN_LINEAR_TIMEOUTS, TCP_BPF_DELACK_MAX,
2928	* TCP_BPF_RTO_MIN, TCP_BPF_SOCK_OPS_CB_FLAGS.
2929	* * IPPROTO_IP, which supports optname IP_TOS.
2930	* * IPPROTO_IPV6, which supports the following optname\ s:
2931	* IPV6_TCLASS, IPV6_AUTOFLOWLABEL.
2932	* Return
2933	* 0 on success, or a negative error in case of failure.
2934	*
2935	* long bpf_skb_adjust_room(struct sk_buff *skb, s32 len_diff, u32 mode, u64 flags)
2936	* Description
2937	* Grow or shrink the room for data in the packet associated to
2938	* skb by len_diff, and according to the selected mode.
2939	*
2940	* By default, the helper will reset any offloaded checksum
2941	* indicator of the skb to CHECKSUM_NONE. This can be avoided
2942	* by the following flag:
2943	*
2944	* * BPF_F_ADJ_ROOM_NO_CSUM_RESET: Do not reset offloaded
2945	* checksum data of the skb to CHECKSUM_NONE.
2946	*
2947	* There are two supported modes at this time:
2948	*
2949	* * BPF_ADJ_ROOM_MAC: Adjust room at the mac layer
2950	* (room space is added or removed between the layer 2 and
2951	* layer 3 headers).
2952	*
2953	* * BPF_ADJ_ROOM_NET: Adjust room at the network layer
2954	* (room space is added or removed between the layer 3 and
2955	* layer 4 headers).
2956	*
2957	* The following flags are supported at this time:
2958	*
2959	* * BPF_F_ADJ_ROOM_FIXED_GSO: Do not adjust gso_size.
2960	* Adjusting mss in this way is not allowed for datagrams.
2961	*
2962	* * BPF_F_ADJ_ROOM_ENCAP_L3_IPV4,
2963	* BPF_F_ADJ_ROOM_ENCAP_L3_IPV6:
2964	* Any new space is reserved to hold a tunnel header.
2965	* Configure skb offsets and other fields accordingly.
2966	*
2967	* * BPF_F_ADJ_ROOM_ENCAP_L4_GRE,
2968	* BPF_F_ADJ_ROOM_ENCAP_L4_UDP:
2969	* Use with ENCAP_L3 flags to further specify the tunnel type.
2970	*
2971	* * BPF_F_ADJ_ROOM_ENCAP_L2\ (len):
2972	* Use with ENCAP_L3/L4 flags to further specify the tunnel
2973	* type; len is the length of the inner MAC header.
2974	*
2975	* * BPF_F_ADJ_ROOM_ENCAP_L2_ETH:
2976	* Use with BPF_F_ADJ_ROOM_ENCAP_L2 flag to further specify the
2977	* L2 type as Ethernet.
2978	*
2979	* * BPF_F_ADJ_ROOM_DECAP_L3_IPV4,
2980	* BPF_F_ADJ_ROOM_DECAP_L3_IPV6:
2981	* Indicate the new IP header version after decapsulating the outer
2982	* IP header. Used when the inner and outer IP versions are different.
2983	*
2984	* A call to this helper is susceptible to change the underlying
2985	* packet buffer. Therefore, at load time, all checks on pointers
2986	* previously done by the verifier are invalidated and must be
2987	* performed again, if the helper is used in combination with
2988	* direct packet access.
2989	* Return
2990	* 0 on success, or a negative error in case of failure.
2991	*
2992	* long bpf_redirect_map(struct bpf_map *map, u64 key, u64 flags)
2993	* Description
2994	* Redirect the packet to the endpoint referenced by map at
2995	* index key. Depending on its type, this map can contain
2996	* references to net devices (for forwarding packets through other
2997	* ports), or to CPUs (for redirecting XDP frames to another CPU;
2998	* but this is only implemented for native XDP (with driver
2999	* support) as of this writing).
3000	*
3001	* The lower two bits of flags are used as the return code if
3002	* the map lookup fails. This is so that the return value can be
3003	* one of the XDP program return codes up to XDP_TX, as chosen
3004	* by the caller. The higher bits of flags can be set to
3005	* BPF_F_BROADCAST or BPF_F_EXCLUDE_INGRESS as defined below.
3006	*
3007	* With BPF_F_BROADCAST the packet will be broadcasted to all the
3008	* interfaces in the map, with BPF_F_EXCLUDE_INGRESS the ingress
3009	* interface will be excluded when do broadcasting.
3010	*
3011	* See also bpf_redirect\ (), which only supports redirecting
3012	* to an ifindex, but doesn't require a map to do so.
3013	* Return
3014	* XDP_REDIRECT on success, or the value of the two lower bits
3015	* of the flags argument on error.
3016	*
3017	* long bpf_sk_redirect_map(struct sk_buff skb, struct bpf_map map, u32 key, u64 flags)
3018	* Description
3019	* Redirect the packet to the socket referenced by map (of type
3020	* BPF_MAP_TYPE_SOCKMAP) at index key. Both ingress and
3021	* egress interfaces can be used for redirection. The
3022	* BPF_F_INGRESS value in flags is used to make the
3023	* distinction (ingress path is selected if the flag is present,
3024	* egress path otherwise). This is the only flag supported for now.
3025	* Return
3026	* SK_PASS on success, or SK_DROP on error.
3027	*
3028	* long bpf_sock_map_update(struct bpf_sock_ops skops, struct bpf_map map, void *key, u64 flags)
3029	* Description
3030	* Add an entry to, or update a map referencing sockets. The
3031	* skops is used as a new value for the entry associated to
3032	* key. flags is one of:
3033	*
3034	* BPF_NOEXIST
3035	* The entry for key must not exist in the map.
3036	* BPF_EXIST
3037	* The entry for key must already exist in the map.
3038	* BPF_ANY
3039	* No condition on the existence of the entry for key.
3040	*
3041	* If the map has eBPF programs (parser and verdict), those will
3042	* be inherited by the socket being added. If the socket is
3043	* already attached to eBPF programs, this results in an error.
3044	* Return
3045	* 0 on success, or a negative error in case of failure.
3046	*
3047	* long bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta)
3048	* Description
3049	* Adjust the address pointed by xdp_md\ ->data_meta by
3050	* delta (which can be positive or negative). Note that this
3051	* operation modifies the address stored in xdp_md\ ->data,
3052	* so the latter must be loaded only after the helper has been
3053	* called.
3054	*
3055	* The use of xdp_md\ ->data_meta is optional and programs
3056	* are not required to use it. The rationale is that when the
3057	* packet is processed with XDP (e.g. as DoS filter), it is
3058	* possible to push further meta data along with it before passing
3059	* to the stack, and to give the guarantee that an ingress eBPF
3060	* program attached as a TC classifier on the same device can pick
3061	* this up for further post-processing. Since TC works with socket
3062	* buffers, it remains possible to set from XDP the mark or
3063	* priority pointers, or other pointers for the socket buffer.
3064	* Having this scratch space generic and programmable allows for
3065	* more flexibility as the user is free to store whatever meta
3066	* data they need.
3067	*
3068	* A call to this helper is susceptible to change the underlying
3069	* packet buffer. Therefore, at load time, all checks on pointers
3070	* previously done by the verifier are invalidated and must be
3071	* performed again, if the helper is used in combination with
3072	* direct packet access.
3073	* Return
3074	* 0 on success, or a negative error in case of failure.
3075	*
3076	* long bpf_perf_event_read_value(struct bpf_map map, u64 flags, struct bpf_perf_event_value buf, u32 buf_size)
3077	* Description
3078	* Read the value of a perf event counter, and store it into buf
3079	* of size buf_size. This helper relies on a map of type
3080	* BPF_MAP_TYPE_PERF_EVENT_ARRAY. The nature of the perf event
3081	* counter is selected when map is updated with perf event file
3082	* descriptors. The map is an array whose size is the number of
3083	* available CPUs, and each cell contains a value relative to one
3084	* CPU. The value to retrieve is indicated by flags, that
3085	* contains the index of the CPU to look up, masked with
3086	* BPF_F_INDEX_MASK. Alternatively, flags can be set to
3087	* BPF_F_CURRENT_CPU to indicate that the value for the
3088	* current CPU should be retrieved.
3089	*
3090	* This helper behaves in a way close to
3091	* bpf_perf_event_read\ () helper, save that instead of
3092	* just returning the value observed, it fills the buf
3093	* structure. This allows for additional data to be retrieved: in
3094	* particular, the enabled and running times (in buf\
3095	* ->enabled and buf\ ->running, respectively) are
3096	* copied. In general, bpf_perf_event_read_value\ () is
3097	* recommended over bpf_perf_event_read\ (), which has some
3098	* ABI issues and provides fewer functionalities.
3099	*
3100	* These values are interesting, because hardware PMU (Performance
3101	* Monitoring Unit) counters are limited resources. When there are
3102	* more PMU based perf events opened than available counters,
3103	* kernel will multiplex these events so each event gets certain
3104	* percentage (but not all) of the PMU time. In case that
3105	* multiplexing happens, the number of samples or counter value
3106	* will not reflect the case compared to when no multiplexing
3107	* occurs. This makes comparison between different runs difficult.
3108	* Typically, the counter value should be normalized before
3109	* comparing to other experiments. The usual normalization is done
3110	* as follows.
3111	*
3112	* ::
3113	*
3114	* normalized_counter = counter * t_enabled / t_running
3115	*
3116	* Where t_enabled is the time enabled for event and t_running is
3117	* the time running for event since last normalization. The
3118	* enabled and running times are accumulated since the perf event
3119	* open. To achieve scaling factor between two invocations of an
3120	* eBPF program, users can use CPU id as the key (which is
3121	* typical for perf array usage model) to remember the previous
3122	* value and do the calculation inside the eBPF program.
3123	* Return
3124	* 0 on success, or a negative error in case of failure.
3125	*
3126	* long bpf_perf_prog_read_value(struct bpf_perf_event_data ctx, struct bpf_perf_event_value buf, u32 buf_size)
3127	* Description
3128	* For an eBPF program attached to a perf event, retrieve the
3129	* value of the event counter associated to ctx and store it in
3130	* the structure pointed by buf and of size buf_size. Enabled
3131	* and running times are also stored in the structure (see
3132	* description of helper bpf_perf_event_read_value\ () for
3133	* more details).
3134	* Return
3135	* 0 on success, or a negative error in case of failure.
3136	*
3137	* long bpf_getsockopt(void bpf_socket, int level, int optname, void optval, int optlen)
3138	* Description
3139	* Emulate a call to getsockopt() on the socket associated to
3140	* bpf_socket, which must be a full socket. The level at
3141	* which the option resides and the name optname of the option
3142	* must be specified, see getsockopt(2) for more information.
3143	* The retrieved value is stored in the structure pointed by
3144	* opval and of length optlen.
3145	*
3146	* bpf_socket should be one of the following:
3147	*
3148	* * struct bpf_sock_ops for BPF_PROG_TYPE_SOCK_OPS.
3149	* * struct bpf_sock_addr for BPF_CGROUP_INET4_CONNECT,
3150	* BPF_CGROUP_INET6_CONNECT and BPF_CGROUP_UNIX_CONNECT.
3151	*
3152	* This helper actually implements a subset of getsockopt().
3153	* It supports the same set of optname\ s that is supported by
3154	* the bpf_setsockopt\ () helper. The exceptions are
3155	* TCP_BPF_* is bpf_setsockopt\ () only and
3156	* TCP_SAVED_SYN is bpf_getsockopt\ () only.
3157	* Return
3158	* 0 on success, or a negative error in case of failure.
3159	*
3160	* long bpf_override_return(struct pt_regs *regs, u64 rc)
3161	* Description
3162	* Used for error injection, this helper uses kprobes to override
3163	* the return value of the probed function, and to set it to rc.
3164	* The first argument is the context regs on which the kprobe
3165	* works.
3166	*
3167	* This helper works by setting the PC (program counter)
3168	* to an override function which is run in place of the original
3169	* probed function. This means the probed function is not run at
3170	* all. The replacement function just returns with the required
3171	* value.
3172	*
3173	* This helper has security implications, and thus is subject to
3174	* restrictions. It is only available if the kernel was compiled
3175	* with the CONFIG_BPF_KPROBE_OVERRIDE configuration
3176	* option, and in this case it only works on functions tagged with
3177	* ALLOW_ERROR_INJECTION in the kernel code.
3178	* Return
3179	* 0
3180	*
3181	* long bpf_sock_ops_cb_flags_set(struct bpf_sock_ops *bpf_sock, int argval)
3182	* Description
3183	* Attempt to set the value of the bpf_sock_ops_cb_flags field
3184	* for the full TCP socket associated to bpf_sock_ops to
3185	* argval.
3186	*
3187	* The primary use of this field is to determine if there should
3188	* be calls to eBPF programs of type
3189	* BPF_PROG_TYPE_SOCK_OPS at various points in the TCP
3190	* code. A program of the same type can change its value, per
3191	* connection and as necessary, when the connection is
3192	* established. This field is directly accessible for reading, but
3193	* this helper must be used for updates in order to return an
3194	* error if an eBPF program tries to set a callback that is not
3195	* supported in the current kernel.
3196	*
3197	* argval is a flag array which can combine these flags:
3198	*
3199	* * BPF_SOCK_OPS_RTO_CB_FLAG (retransmission time out)
3200	* * BPF_SOCK_OPS_RETRANS_CB_FLAG (retransmission)
3201	* * BPF_SOCK_OPS_STATE_CB_FLAG (TCP state change)
3202	* * BPF_SOCK_OPS_RTT_CB_FLAG (every RTT)
3203	*
3204	* Therefore, this function can be used to clear a callback flag by
3205	* setting the appropriate bit to zero. e.g. to disable the RTO
3206	* callback:
3207	*
3208	* bpf_sock_ops_cb_flags_set(bpf_sock,
3209	* bpf_sock->bpf_sock_ops_cb_flags & ~BPF_SOCK_OPS_RTO_CB_FLAG)
3210	*
3211	* Here are some examples of where one could call such eBPF
3212	* program:
3213	*
3214	* * When RTO fires.
3215	* * When a packet is retransmitted.
3216	* * When the connection terminates.
3217	* * When a packet is sent.
3218	* * When a packet is received.
3219	* Return
3220	* Code -EINVAL if the socket is not a full TCP socket;
3221	* otherwise, a positive number containing the bits that could not
3222	* be set is returned (which comes down to 0 if all bits were set
3223	* as required).
3224	*
3225	* long bpf_msg_redirect_map(struct sk_msg_buff msg, struct bpf_map map, u32 key, u64 flags)
3226	* Description
3227	* This helper is used in programs implementing policies at the
3228	* socket level. If the message msg is allowed to pass (i.e. if
3229	* the verdict eBPF program returns SK_PASS), redirect it to
3230	* the socket referenced by map (of type
3231	* BPF_MAP_TYPE_SOCKMAP) at index key. Both ingress and
3232	* egress interfaces can be used for redirection. The
3233	* BPF_F_INGRESS value in flags is used to make the
3234	* distinction (ingress path is selected if the flag is present,
3235	* egress path otherwise). This is the only flag supported for now.
3236	* Return
3237	* SK_PASS on success, or SK_DROP on error.
3238	*
3239	* long bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes)
3240	* Description
3241	* For socket policies, apply the verdict of the eBPF program to
3242	* the next bytes (number of bytes) of message msg.
3243	*
3244	* For example, this helper can be used in the following cases:
3245	*
3246	* * A single sendmsg\ () or sendfile\ () system call
3247	* contains multiple logical messages that the eBPF program is
3248	* supposed to read and for which it should apply a verdict.
3249	* * An eBPF program only cares to read the first bytes of a
3250	* msg. If the message has a large payload, then setting up
3251	* and calling the eBPF program repeatedly for all bytes, even
3252	* though the verdict is already known, would create unnecessary
3253	* overhead.
3254	*
3255	* When called from within an eBPF program, the helper sets a
3256	* counter internal to the BPF infrastructure, that is used to
3257	* apply the last verdict to the next bytes. If bytes is
3258	* smaller than the current data being processed from a
3259	* sendmsg\ () or sendfile\ () system call, the first
3260	* bytes will be sent and the eBPF program will be re-run with
3261	* the pointer for start of data pointing to byte number bytes
3262	* + 1. If bytes is larger than the current data being
3263	* processed, then the eBPF verdict will be applied to multiple
3264	* sendmsg\ () or sendfile\ () calls until bytes are
3265	* consumed.
3266	*
3267	* Note that if a socket closes with the internal counter holding
3268	* a non-zero value, this is not a problem because data is not
3269	* being buffered for bytes and is sent as it is received.
3270	* Return
3271	* 0
3272	*
3273	* long bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes)
3274	* Description
3275	* For socket policies, prevent the execution of the verdict eBPF
3276	* program for message msg until bytes (byte number) have been
3277	* accumulated.
3278	*
3279	* This can be used when one needs a specific number of bytes
3280	* before a verdict can be assigned, even if the data spans
3281	* multiple sendmsg\ () or sendfile\ () calls. The extreme
3282	* case would be a user calling sendmsg\ () repeatedly with
3283	* 1-byte long message segments. Obviously, this is bad for
3284	* performance, but it is still valid. If the eBPF program needs
3285	* bytes bytes to validate a header, this helper can be used to
3286	* prevent the eBPF program to be called again until bytes have
3287	* been accumulated.
3288	* Return
3289	* 0
3290	*
3291	* long bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags)
3292	* Description
3293	* For socket policies, pull in non-linear data from user space
3294	* for msg and set pointers msg\ ->data and msg\
3295	* ->data_end to start and end bytes offsets into msg,
3296	* respectively.
3297	*
3298	* If a program of type BPF_PROG_TYPE_SK_MSG is run on a
3299	* msg it can only parse data that the (data, data_end)
3300	* pointers have already consumed. For sendmsg\ () hooks this
3301	* is likely the first scatterlist element. But for calls relying
3302	* on the sendpage handler (e.g. sendfile\ ()) this will
3303	* be the range (0, 0) because the data is shared with
3304	* user space and by default the objective is to avoid allowing
3305	* user space to modify data while (or after) eBPF verdict is
3306	* being decided. This helper can be used to pull in data and to
3307	* set the start and end pointer to given values. Data will be
3308	* copied if necessary (i.e. if data was not linear and if start
3309	* and end pointers do not point to the same chunk).
3310	*
3311	* A call to this helper is susceptible to change the underlying
3312	* packet buffer. Therefore, at load time, all checks on pointers
3313	* previously done by the verifier are invalidated and must be
3314	* performed again, if the helper is used in combination with
3315	* direct packet access.
3316	*
3317	* All values for flags are reserved for future usage, and must
3318	* be left at zero.
3319	* Return
3320	* 0 on success, or a negative error in case of failure.
3321	*
3322	* long bpf_bind(struct bpf_sock_addr ctx, struct sockaddr addr, int addr_len)
3323	* Description
3324	* Bind the socket associated to ctx to the address pointed by
3325	* addr, of length addr_len. This allows for making outgoing
3326	* connection from the desired IP address, which can be useful for
3327	* example when all processes inside a cgroup should use one
3328	* single IP address on a host that has multiple IP configured.
3329	*
3330	* This helper works for IPv4 and IPv6, TCP and UDP sockets. The
3331	* domain (addr\ ->sa_family) must be AF_INET (or
3332	* AF_INET6). It's advised to pass zero port (sin_port
3333	* or sin6_port) which triggers IP_BIND_ADDRESS_NO_PORT-like
3334	* behavior and lets the kernel efficiently pick up an unused
3335	* port as long as 4-tuple is unique. Passing non-zero port might
3336	* lead to degraded performance.
3337	* Return
3338	* 0 on success, or a negative error in case of failure.
3339	*
3340	* long bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta)
3341	* Description
3342	* Adjust (move) xdp_md\ ->data_end by delta bytes. It is
3343	* possible to both shrink and grow the packet tail.
3344	* Shrink done via delta being a negative integer.
3345	*
3346	* A call to this helper is susceptible to change the underlying
3347	* packet buffer. Therefore, at load time, all checks on pointers
3348	* previously done by the verifier are invalidated and must be
3349	* performed again, if the helper is used in combination with
3350	* direct packet access.
3351	* Return
3352	* 0 on success, or a negative error in case of failure.
3353	*
3354	* long bpf_skb_get_xfrm_state(struct sk_buff skb, u32 index, struct bpf_xfrm_state xfrm_state, u32 size, u64 flags)
3355	* Description
3356	* Retrieve the XFRM state (IP transform framework, see also
3357	* ip-xfrm(8)) at index in XFRM "security path" for skb.
3358	*
3359	* The retrieved value is stored in the struct bpf_xfrm_state
3360	* pointed by xfrm_state and of length size.
3361	*
3362	* All values for flags are reserved for future usage, and must
3363	* be left at zero.
3364	*
3365	* This helper is available only if the kernel was compiled with
3366	* CONFIG_XFRM configuration option.
3367	* Return
3368	* 0 on success, or a negative error in case of failure.
3369	*
3370	* long bpf_get_stack(void ctx, void buf, u32 size, u64 flags)
3371	* Description
3372	* Return a user or a kernel stack in bpf program provided buffer.
3373	* To achieve this, the helper needs ctx, which is a pointer
3374	* to the context on which the tracing program is executed.
3375	* To store the stacktrace, the bpf program provides buf with
3376	* a nonnegative size.
3377	*
3378	* The last argument, flags, holds the number of stack frames to
3379	* skip (from 0 to 255), masked with
3380	* BPF_F_SKIP_FIELD_MASK. The next bits can be used to set
3381	* the following flags:
3382	*
3383	* BPF_F_USER_STACK
3384	* Collect a user space stack instead of a kernel stack.
3385	* BPF_F_USER_BUILD_ID
3386	* Collect (build_id, file_offset) instead of ips for user
3387	* stack, only valid if BPF_F_USER_STACK is also
3388	* specified.
3389	*
3390	* file_offset is an offset relative to the beginning
3391	* of the executable or shared object file backing the vma
3392	* which the ip falls in. It is not an offset relative
3393	* to that object's base address. Accordingly, it must be
3394	* adjusted by adding (sh_addr - sh_offset), where
3395	* sh_{addr,offset} correspond to the executable section
3396	* containing file_offset in the object, for comparisons
3397	* to symbols' st_value to be valid.
3398	*
3399	* bpf_get_stack\ () can collect up to
3400	* PERF_MAX_STACK_DEPTH both kernel and user frames, subject
3401	* to sufficient large buffer size. Note that
3402	* this limit can be controlled with the sysctl program, and
3403	* that it should be manually increased in order to profile long
3404	* user stacks (such as stacks for Java programs). To do so, use:
3405	*
3406	* ::
3407	*
3408	* # sysctl kernel.perf_event_max_stack=<new value>
3409	* Return
3410	* The non-negative copied buf length equal to or less than
3411	* size on success, or a negative error in case of failure.
3412	*
3413	* long bpf_skb_load_bytes_relative(const void skb, u32 offset, void to, u32 len, u32 start_header)
3414	* Description
3415	* This helper is similar to bpf_skb_load_bytes\ () in that
3416	* it provides an easy way to load len bytes from offset
3417	* from the packet associated to skb, into the buffer pointed
3418	* by to. The difference to bpf_skb_load_bytes\ () is that
3419	* a fifth argument start_header exists in order to select a
3420	* base offset to start from. start_header can be one of:
3421	*
3422	* BPF_HDR_START_MAC
3423	* Base offset to load data from is skb's mac header.
3424	* BPF_HDR_START_NET
3425	* Base offset to load data from is skb's network header.
3426	*
3427	* In general, "direct packet access" is the preferred method to
3428	* access packet data, however, this helper is in particular useful
3429	* in socket filters where skb\ ->data does not always point
3430	* to the start of the mac header and where "direct packet access"
3431	* is not available.
3432	* Return
3433	* 0 on success, or a negative error in case of failure.
3434	*
3435	* long bpf_fib_lookup(void ctx, struct bpf_fib_lookup params, int plen, u32 flags)
3436	* Description
3437	* Do FIB lookup in kernel tables using parameters in params.
3438	* If lookup is successful and result shows packet is to be
3439	* forwarded, the neighbor tables are searched for the nexthop.
3440	* If successful (ie., FIB lookup shows forwarding and nexthop
3441	* is resolved), the nexthop address is returned in ipv4_dst
3442	* or ipv6_dst based on family, smac is set to mac address of
3443	* egress device, dmac is set to nexthop mac address, rt_metric
3444	* is set to metric from route (IPv4/IPv6 only), and ifindex
3445	* is set to the device index of the nexthop from the FIB lookup.
3446	*
3447	* plen argument is the size of the passed in struct.
3448	* flags argument can be a combination of one or more of the
3449	* following values:
3450	*
3451	* BPF_FIB_LOOKUP_DIRECT
3452	* Do a direct table lookup vs full lookup using FIB
3453	* rules.
3454	* BPF_FIB_LOOKUP_TBID
3455	* Used with BPF_FIB_LOOKUP_DIRECT.
3456	* Use the routing table ID present in params->tbid
3457	* for the fib lookup.
3458	* BPF_FIB_LOOKUP_OUTPUT
3459	* Perform lookup from an egress perspective (default is
3460	* ingress).
3461	* BPF_FIB_LOOKUP_SKIP_NEIGH
3462	* Skip the neighbour table lookup. params->dmac
3463	* and params->smac will not be set as output. A common
3464	* use case is to call bpf_redirect_neigh\ () after
3465	* doing bpf_fib_lookup\ ().
3466	* BPF_FIB_LOOKUP_SRC
3467	* Derive and set source IP addr in params->ipv{4,6}_src
3468	* for the nexthop. If the src addr cannot be derived,
3469	* BPF_FIB_LKUP_RET_NO_SRC_ADDR is returned. In this
3470	* case, params->dmac and params->smac are not set either.
3471	* BPF_FIB_LOOKUP_MARK
3472	* Use the mark present in params->mark for the fib lookup.
3473	* This option should not be used with BPF_FIB_LOOKUP_DIRECT,
3474	* as it only has meaning for full lookups.
3475	*
3476	* ctx is either struct xdp_md for XDP programs or
3477	* struct sk_buff tc cls_act programs.
3478	* Return
3479	* * < 0 if any input argument is invalid
3480	* * 0 on success (packet is forwarded, nexthop neighbor exists)
3481	* * > 0 one of BPF_FIB_LKUP_RET_ codes explaining why the
3482	* packet is not forwarded or needs assist from full stack
3483	*
3484	* If lookup fails with BPF_FIB_LKUP_RET_FRAG_NEEDED, then the MTU
3485	* was exceeded and output params->mtu_result contains the MTU.
3486	*
3487	* long bpf_sock_hash_update(struct bpf_sock_ops skops, struct bpf_map map, void *key, u64 flags)
3488	* Description
3489	* Add an entry to, or update a sockhash map referencing sockets.
3490	* The skops is used as a new value for the entry associated to
3491	* key. flags is one of:
3492	*
3493	* BPF_NOEXIST
3494	* The entry for key must not exist in the map.
3495	* BPF_EXIST
3496	* The entry for key must already exist in the map.
3497	* BPF_ANY
3498	* No condition on the existence of the entry for key.
3499	*
3500	* If the map has eBPF programs (parser and verdict), those will
3501	* be inherited by the socket being added. If the socket is
3502	* already attached to eBPF programs, this results in an error.
3503	* Return
3504	* 0 on success, or a negative error in case of failure.
3505	*
3506	* long bpf_msg_redirect_hash(struct sk_msg_buff msg, struct bpf_map map, void *key, u64 flags)
3507	* Description
3508	* This helper is used in programs implementing policies at the
3509	* socket level. If the message msg is allowed to pass (i.e. if
3510	* the verdict eBPF program returns SK_PASS), redirect it to
3511	* the socket referenced by map (of type
3512	* BPF_MAP_TYPE_SOCKHASH) using hash key. Both ingress and
3513	* egress interfaces can be used for redirection. The
3514	* BPF_F_INGRESS value in flags is used to make the
3515	* distinction (ingress path is selected if the flag is present,
3516	* egress path otherwise). This is the only flag supported for now.
3517	* Return
3518	* SK_PASS on success, or SK_DROP on error.
3519	*
3520	* long bpf_sk_redirect_hash(struct sk_buff skb, struct bpf_map map, void *key, u64 flags)
3521	* Description
3522	* This helper is used in programs implementing policies at the
3523	* skb socket level. If the sk_buff skb is allowed to pass (i.e.
3524	* if the verdict eBPF program returns SK_PASS), redirect it
3525	* to the socket referenced by map (of type
3526	* BPF_MAP_TYPE_SOCKHASH) using hash key. Both ingress and
3527	* egress interfaces can be used for redirection. The
3528	* BPF_F_INGRESS value in flags is used to make the
3529	* distinction (ingress path is selected if the flag is present,
3530	* egress otherwise). This is the only flag supported for now.
3531	* Return
3532	* SK_PASS on success, or SK_DROP on error.
3533	*
3534	* long bpf_lwt_push_encap(struct sk_buff skb, u32 type, void hdr, u32 len)
3535	* Description
3536	* Encapsulate the packet associated to skb within a Layer 3
3537	* protocol header. This header is provided in the buffer at
3538	* address hdr, with len its size in bytes. type indicates
3539	* the protocol of the header and can be one of:
3540	*
3541	* BPF_LWT_ENCAP_SEG6
3542	* IPv6 encapsulation with Segment Routing Header
3543	* (struct ipv6_sr_hdr). hdr only contains the SRH,
3544	* the IPv6 header is computed by the kernel.
3545	* BPF_LWT_ENCAP_SEG6_INLINE
3546	* Only works if skb contains an IPv6 packet. Insert a
3547	* Segment Routing Header (struct ipv6_sr_hdr) inside
3548	* the IPv6 header.
3549	* BPF_LWT_ENCAP_IP
3550	* IP encapsulation (GRE/GUE/IPIP/etc). The outer header
3551	* must be IPv4 or IPv6, followed by zero or more
3552	* additional headers, up to LWT_BPF_MAX_HEADROOM
3553	* total bytes in all prepended headers. Please note that
3554	* if skb_is_gso\ (skb) is true, no more than two
3555	* headers can be prepended, and the inner header, if
3556	* present, should be either GRE or UDP/GUE.
3557	*
3558	* BPF_LWT_ENCAP_SEG6\ \* types can be called by BPF programs
3559	* of type BPF_PROG_TYPE_LWT_IN; BPF_LWT_ENCAP_IP type can
3560	* be called by bpf programs of types BPF_PROG_TYPE_LWT_IN and
3561	* BPF_PROG_TYPE_LWT_XMIT.
3562	*
3563	* A call to this helper is susceptible to change the underlying
3564	* packet buffer. Therefore, at load time, all checks on pointers
3565	* previously done by the verifier are invalidated and must be
3566	* performed again, if the helper is used in combination with
3567	* direct packet access.
3568	* Return
3569	* 0 on success, or a negative error in case of failure.
3570	*
3571	* long bpf_lwt_seg6_store_bytes(struct sk_buff skb, u32 offset, const void from, u32 len)
3572	* Description
3573	* Store len bytes from address from into the packet
3574	* associated to skb, at offset. Only the flags, tag and TLVs
3575	* inside the outermost IPv6 Segment Routing Header can be
3576	* modified through this helper.
3577	*
3578	* A call to this helper is susceptible to change the underlying
3579	* packet buffer. Therefore, at load time, all checks on pointers
3580	* previously done by the verifier are invalidated and must be
3581	* performed again, if the helper is used in combination with
3582	* direct packet access.
3583	* Return
3584	* 0 on success, or a negative error in case of failure.
3585	*
3586	* long bpf_lwt_seg6_adjust_srh(struct sk_buff *skb, u32 offset, s32 delta)
3587	* Description
3588	* Adjust the size allocated to TLVs in the outermost IPv6
3589	* Segment Routing Header contained in the packet associated to
3590	* skb, at position offset by delta bytes. Only offsets
3591	* after the segments are accepted. delta can be as well
3592	* positive (growing) as negative (shrinking).
3593	*
3594	* A call to this helper is susceptible to change the underlying
3595	* packet buffer. Therefore, at load time, all checks on pointers
3596	* previously done by the verifier are invalidated and must be
3597	* performed again, if the helper is used in combination with
3598	* direct packet access.
3599	* Return
3600	* 0 on success, or a negative error in case of failure.
3601	*
3602	* long bpf_lwt_seg6_action(struct sk_buff skb, u32 action, void param, u32 param_len)
3603	* Description
3604	* Apply an IPv6 Segment Routing action of type action to the
3605	* packet associated to skb. Each action takes a parameter
3606	* contained at address param, and of length param_len bytes.
3607	* action can be one of:
3608	*
3609	* SEG6_LOCAL_ACTION_END_X
3610	* End.X action: Endpoint with Layer-3 cross-connect.
3611	* Type of param: struct in6_addr.
3612	* SEG6_LOCAL_ACTION_END_T
3613	* End.T action: Endpoint with specific IPv6 table lookup.
3614	* Type of param: int.
3615	* SEG6_LOCAL_ACTION_END_B6
3616	* End.B6 action: Endpoint bound to an SRv6 policy.
3617	* Type of param: struct ipv6_sr_hdr.
3618	* SEG6_LOCAL_ACTION_END_B6_ENCAP
3619	* End.B6.Encap action: Endpoint bound to an SRv6
3620	* encapsulation policy.
3621	* Type of param: struct ipv6_sr_hdr.
3622	*
3623	* A call to this helper is susceptible to change the underlying
3624	* packet buffer. Therefore, at load time, all checks on pointers
3625	* previously done by the verifier are invalidated and must be
3626	* performed again, if the helper is used in combination with
3627	* direct packet access.
3628	* Return
3629	* 0 on success, or a negative error in case of failure.
3630	*
3631	* long bpf_rc_repeat(void *ctx)
3632	* Description
3633	* This helper is used in programs implementing IR decoding, to
3634	* report a successfully decoded repeat key message. This delays
3635	* the generation of a key up event for previously generated
3636	* key down event.
3637	*
3638	* Some IR protocols like NEC have a special IR message for
3639	* repeating last button, for when a button is held down.
3640	*
3641	* The ctx should point to the lirc sample as passed into
3642	* the program.
3643	*
3644	* This helper is only available is the kernel was compiled with
3645	* the CONFIG_BPF_LIRC_MODE2 configuration option set to
3646	* "y".
3647	* Return
3648	* 0
3649	*
3650	* long bpf_rc_keydown(void *ctx, u32 protocol, u64 scancode, u32 toggle)
3651	* Description
3652	* This helper is used in programs implementing IR decoding, to
3653	* report a successfully decoded key press with scancode,
3654	* toggle value in the given protocol. The scancode will be
3655	* translated to a keycode using the rc keymap, and reported as
3656	* an input key down event. After a period a key up event is
3657	* generated. This period can be extended by calling either
3658	* bpf_rc_keydown\ () again with the same values, or calling
3659	* bpf_rc_repeat\ ().
3660	*
3661	* Some protocols include a toggle bit, in case the button was
3662	* released and pressed again between consecutive scancodes.
3663	*
3664	* The ctx should point to the lirc sample as passed into
3665	* the program.
3666	*
3667	* The protocol is the decoded protocol number (see
3668	* enum rc_proto for some predefined values).
3669	*
3670	* This helper is only available is the kernel was compiled with
3671	* the CONFIG_BPF_LIRC_MODE2 configuration option set to
3672	* "y".
3673	* Return
3674	* 0
3675	*
3676	* u64 bpf_skb_cgroup_id(struct sk_buff *skb)
3677	* Description
3678	* Return the cgroup v2 id of the socket associated with the skb.
3679	* This is roughly similar to the bpf_get_cgroup_classid\ ()
3680	* helper for cgroup v1 by providing a tag resp. identifier that
3681	* can be matched on or used for map lookups e.g. to implement
3682	* policy. The cgroup v2 id of a given path in the hierarchy is
3683	* exposed in user space through the f_handle API in order to get
3684	* to the same 64-bit id.
3685	*
3686	* This helper can be used on TC egress path, but not on ingress,
3687	* and is available only if the kernel was compiled with the
3688	* CONFIG_SOCK_CGROUP_DATA configuration option.
3689	* Return
3690	* The id is returned or 0 in case the id could not be retrieved.
3691	*
3692	* u64 bpf_get_current_cgroup_id(void)
3693	* Description
3694	* Get the current cgroup id based on the cgroup within which
3695	* the current task is running.
3696	* Return
3697	* A 64-bit integer containing the current cgroup id based
3698	* on the cgroup within which the current task is running.
3699	*
3700	* void bpf_get_local_storage(void map, u64 flags)
3701	* Description
3702	* Get the pointer to the local storage area.
3703	* The type and the size of the local storage is defined
3704	* by the map argument.
3705	* The flags meaning is specific for each map type,
3706	* and has to be 0 for cgroup local storage.
3707	*
3708	* Depending on the BPF program type, a local storage area
3709	* can be shared between multiple instances of the BPF program,
3710	* running simultaneously.
3711	*
3712	* A user should care about the synchronization by himself.
3713	* For example, by using the BPF_ATOMIC instructions to alter
3714	* the shared data.
3715	* Return
3716	* A pointer to the local storage area.
3717	*
3718	* long bpf_sk_select_reuseport(struct sk_reuseport_md reuse, struct bpf_map map, void *key, u64 flags)
3719	* Description
3720	* Select a SO_REUSEPORT socket from a
3721	* BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map.
3722	* It checks the selected socket is matching the incoming
3723	* request in the socket buffer.
3724	* Return
3725	* 0 on success, or a negative error in case of failure.
3726	*
3727	* u64 bpf_skb_ancestor_cgroup_id(struct sk_buff *skb, int ancestor_level)
3728	* Description
3729	* Return id of cgroup v2 that is ancestor of cgroup associated
3730	* with the skb at the ancestor_level. The root cgroup is at
3731	* ancestor_level zero and each step down the hierarchy
3732	* increments the level. If ancestor_level == level of cgroup
3733	* associated with skb, then return value will be same as that
3734	* of bpf_skb_cgroup_id\ ().
3735	*
3736	* The helper is useful to implement policies based on cgroups
3737	* that are upper in hierarchy than immediate cgroup associated
3738	* with skb.
3739	*
3740	* The format of returned id and helper limitations are same as in
3741	* bpf_skb_cgroup_id\ ().
3742	* Return
3743	* The id is returned or 0 in case the id could not be retrieved.
3744	*
3745	* struct bpf_sock bpf_sk_lookup_tcp(void ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
3746	* Description
3747	* Look for TCP socket matching tuple, optionally in a child
3748	* network namespace netns. The return value must be checked,
3749	* and if non-NULL, released via bpf_sk_release\ ().
3750	*
3751	* The ctx should point to the context of the program, such as
3752	* the skb or socket (depending on the hook in use). This is used
3753	* to determine the base network namespace for the lookup.
3754	*
3755	* tuple_size must be one of:
3756	*
3757	* sizeof\ (tuple\ ->ipv4)
3758	* Look for an IPv4 socket.
3759	* sizeof\ (tuple\ ->ipv6)
3760	* Look for an IPv6 socket.
3761	*
3762	* If the netns is a negative signed 32-bit integer, then the
3763	* socket lookup table in the netns associated with the ctx
3764	* will be used. For the TC hooks, this is the netns of the device
3765	* in the skb. For socket hooks, this is the netns of the socket.
3766	* If netns is any other signed 32-bit value greater than or
3767	* equal to zero then it specifies the ID of the netns relative to
3768	* the netns associated with the ctx. netns values beyond the
3769	* range of 32-bit integers are reserved for future use.
3770	*
3771	* All values for flags are reserved for future usage, and must
3772	* be left at zero.
3773	*
3774	* This helper is available only if the kernel was compiled with
3775	* CONFIG_NET configuration option.
3776	* Return
3777	* Pointer to struct bpf_sock, or NULL in case of failure.
3778	* For sockets with reuseport option, the struct bpf_sock
3779	* result is from reuse\ ->socks\ [] using the hash of the
3780	* tuple.
3781	*
3782	* struct bpf_sock bpf_sk_lookup_udp(void ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
3783	* Description
3784	* Look for UDP socket matching tuple, optionally in a child
3785	* network namespace netns. The return value must be checked,
3786	* and if non-NULL, released via bpf_sk_release\ ().
3787	*
3788	* The ctx should point to the context of the program, such as
3789	* the skb or socket (depending on the hook in use). This is used
3790	* to determine the base network namespace for the lookup.
3791	*
3792	* tuple_size must be one of:
3793	*
3794	* sizeof\ (tuple\ ->ipv4)
3795	* Look for an IPv4 socket.
3796	* sizeof\ (tuple\ ->ipv6)
3797	* Look for an IPv6 socket.
3798	*
3799	* If the netns is a negative signed 32-bit integer, then the
3800	* socket lookup table in the netns associated with the ctx
3801	* will be used. For the TC hooks, this is the netns of the device
3802	* in the skb. For socket hooks, this is the netns of the socket.
3803	* If netns is any other signed 32-bit value greater than or
3804	* equal to zero then it specifies the ID of the netns relative to
3805	* the netns associated with the ctx. netns values beyond the
3806	* range of 32-bit integers are reserved for future use.
3807	*
3808	* All values for flags are reserved for future usage, and must
3809	* be left at zero.
3810	*
3811	* This helper is available only if the kernel was compiled with
3812	* CONFIG_NET configuration option.
3813	* Return
3814	* Pointer to struct bpf_sock, or NULL in case of failure.
3815	* For sockets with reuseport option, the struct bpf_sock
3816	* result is from reuse\ ->socks\ [] using the hash of the
3817	* tuple.
3818	*
3819	* long bpf_sk_release(void *sock)
3820	* Description
3821	* Release the reference held by sock. sock must be a
3822	* non-NULL pointer that was returned from
3823	* bpf_sk_lookup_xxx\ ().
3824	* Return
3825	* 0 on success, or a negative error in case of failure.
3826	*
3827	* long bpf_map_push_elem(struct bpf_map map, const void value, u64 flags)
3828	* Description
3829	* Push an element value in map. flags is one of:
3830	*
3831	* BPF_EXIST
3832	* If the queue/stack is full, the oldest element is
3833	* removed to make room for this.
3834	* Return
3835	* 0 on success, or a negative error in case of failure.
3836	*
3837	* long bpf_map_pop_elem(struct bpf_map map, void value)
3838	* Description
3839	* Pop an element from map.
3840	* Return
3841	* 0 on success, or a negative error in case of failure.
3842	*
3843	* long bpf_map_peek_elem(struct bpf_map map, void value)
3844	* Description
3845	* Get an element from map without removing it.
3846	* Return
3847	* 0 on success, or a negative error in case of failure.
3848	*
3849	* long bpf_msg_push_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
3850	* Description
3851	* For socket policies, insert len bytes into msg at offset
3852	* start.
3853	*
3854	* If a program of type BPF_PROG_TYPE_SK_MSG is run on a
3855	* msg it may want to insert metadata or options into the msg.
3856	* This can later be read and used by any of the lower layer BPF
3857	* hooks.
3858	*
3859	* This helper may fail if under memory pressure (a malloc
3860	* fails) in these cases BPF programs will get an appropriate
3861	* error and BPF programs will need to handle them.
3862	* Return
3863	* 0 on success, or a negative error in case of failure.
3864	*
3865	* long bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 len, u64 flags)
3866	* Description
3867	* Will remove len bytes from a msg starting at byte start.
3868	* This may result in ENOMEM errors under certain situations if
3869	* an allocation and copy are required due to a full ring buffer.
3870	* However, the helper will try to avoid doing the allocation
3871	* if possible. Other errors can occur if input parameters are
3872	* invalid either due to start byte not being valid part of msg
3873	* payload and/or pop value being to large.
3874	* Return
3875	* 0 on success, or a negative error in case of failure.
3876	*
3877	* long bpf_rc_pointer_rel(void *ctx, s32 rel_x, s32 rel_y)
3878	* Description
3879	* This helper is used in programs implementing IR decoding, to
3880	* report a successfully decoded pointer movement.
3881	*
3882	* The ctx should point to the lirc sample as passed into
3883	* the program.
3884	*
3885	* This helper is only available is the kernel was compiled with
3886	* the CONFIG_BPF_LIRC_MODE2 configuration option set to
3887	* "y".
3888	* Return
3889	* 0
3890	*
3891	* long bpf_spin_lock(struct bpf_spin_lock *lock)
3892	* Description
3893	* Acquire a spinlock represented by the pointer lock, which is
3894	* stored as part of a value of a map. Taking the lock allows to
3895	* safely update the rest of the fields in that value. The
3896	* spinlock can (and must) later be released with a call to
3897	* bpf_spin_unlock\ (\ lock\ ).
3898	*
3899	* Spinlocks in BPF programs come with a number of restrictions
3900	* and constraints:
3901	*
3902	* * bpf_spin_lock objects are only allowed inside maps of
3903	* types BPF_MAP_TYPE_HASH and BPF_MAP_TYPE_ARRAY (this
3904	* list could be extended in the future).
3905	* * BTF description of the map is mandatory.
3906	* * The BPF program can take ONE lock at a time, since taking two
3907	* or more could cause dead locks.
3908	* * Only one struct bpf_spin_lock is allowed per map element.
3909	* * When the lock is taken, calls (either BPF to BPF or helpers)
3910	* are not allowed.
3911	* * The BPF_LD_ABS and BPF_LD_IND instructions are not
3912	* allowed inside a spinlock-ed region.
3913	* * The BPF program MUST call bpf_spin_unlock\ () to release
3914	* the lock, on all execution paths, before it returns.
3915	* * The BPF program can access struct bpf_spin_lock only via
3916	* the bpf_spin_lock\ () and bpf_spin_unlock\ ()
3917	* helpers. Loading or storing data into the **struct
3918	* bpf_spin_lock** lock\ ; field of a map is not allowed.
3919	* * To use the bpf_spin_lock\ () helper, the BTF description
3920	* of the map value must be a struct and have **struct
3921	* bpf_spin_lock** anyname\ ; field at the top level.
3922	* Nested lock inside another struct is not allowed.
3923	* * The struct bpf_spin_lock lock field in a map value must
3924	* be aligned on a multiple of 4 bytes in that value.
3925	* * Syscall with command BPF_MAP_LOOKUP_ELEM does not copy
3926	* the bpf_spin_lock field to user space.
3927	* * Syscall with command BPF_MAP_UPDATE_ELEM, or update from
3928	* a BPF program, do not update the bpf_spin_lock field.
3929	* * bpf_spin_lock cannot be on the stack or inside a
3930	* networking packet (it can only be inside of a map values).
3931	* * bpf_spin_lock is available to root only.
3932	* * Tracing programs and socket filter programs cannot use
3933	* bpf_spin_lock\ () due to insufficient preemption checks
3934	* (but this may change in the future).
3935	* * bpf_spin_lock is not allowed in inner maps of map-in-map.
3936	* Return
3937	* 0
3938	*
3939	* long bpf_spin_unlock(struct bpf_spin_lock *lock)
3940	* Description
3941	* Release the lock previously locked by a call to
3942	* bpf_spin_lock\ (\ lock\ ).
3943	* Return
3944	* 0
3945	*
3946	* struct bpf_sock bpf_sk_fullsock(struct bpf_sock sk)
3947	* Description
3948	* This helper gets a struct bpf_sock pointer such
3949	* that all the fields in this bpf_sock can be accessed.
3950	* Return
3951	* A struct bpf_sock pointer on success, or NULL in
3952	* case of failure.
3953	*
3954	* struct bpf_tcp_sock bpf_tcp_sock(struct bpf_sock sk)
3955	* Description
3956	* This helper gets a struct bpf_tcp_sock pointer from a
3957	* struct bpf_sock pointer.
3958	* Return
3959	* A struct bpf_tcp_sock pointer on success, or NULL in
3960	* case of failure.
3961	*
3962	* long bpf_skb_ecn_set_ce(struct sk_buff *skb)
3963	* Description
3964	* Set ECN (Explicit Congestion Notification) field of IP header
3965	* to CE (Congestion Encountered) if current value is ECT
3966	* (ECN Capable Transport). Otherwise, do nothing. Works with IPv6
3967	* and IPv4.
3968	* Return
3969	* 1 if the CE flag is set (either by the current helper call
3970	* or because it was already present), 0 if it is not set.
3971	*
3972	* struct bpf_sock bpf_get_listener_sock(struct bpf_sock sk)
3973	* Description
3974	* Return a struct bpf_sock pointer in TCP_LISTEN state.
3975	* bpf_sk_release\ () is unnecessary and not allowed.
3976	* Return
3977	* A struct bpf_sock pointer on success, or NULL in
3978	* case of failure.
3979	*
3980	* struct bpf_sock bpf_skc_lookup_tcp(void ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
3981	* Description
3982	* Look for TCP socket matching tuple, optionally in a child
3983	* network namespace netns. The return value must be checked,
3984	* and if non-NULL, released via bpf_sk_release\ ().
3985	*
3986	* This function is identical to bpf_sk_lookup_tcp\ (), except
3987	* that it also returns timewait or request sockets. Use
3988	* bpf_sk_fullsock\ () or bpf_tcp_sock\ () to access the
3989	* full structure.
3990	*
3991	* This helper is available only if the kernel was compiled with
3992	* CONFIG_NET configuration option.
3993	* Return
3994	* Pointer to struct bpf_sock, or NULL in case of failure.
3995	* For sockets with reuseport option, the struct bpf_sock
3996	* result is from reuse\ ->socks\ [] using the hash of the
3997	* tuple.
3998	*
3999	* long bpf_tcp_check_syncookie(void sk, void iph, u32 iph_len, struct tcphdr *th, u32 th_len)
4000	* Description
4001	* Check whether iph and th contain a valid SYN cookie ACK for
4002	* the listening socket in sk.
4003	*
4004	* iph points to the start of the IPv4 or IPv6 header, while
4005	* iph_len contains sizeof\ (struct iphdr) or
4006	* sizeof\ (struct ipv6hdr).
4007	*
4008	* th points to the start of the TCP header, while th_len
4009	* contains the length of the TCP header (at least
4010	* sizeof\ (struct tcphdr)).
4011	* Return
4012	* 0 if iph and th are a valid SYN cookie ACK, or a negative
4013	* error otherwise.
4014	*
4015	* long bpf_sysctl_get_name(struct bpf_sysctl ctx, char buf, size_t buf_len, u64 flags)
4016	* Description
4017	* Get name of sysctl in /proc/sys/ and copy it into provided by
4018	* program buffer buf of size buf_len.
4019	*
4020	* The buffer is always NUL terminated, unless it's zero-sized.
4021	*
4022	* If flags is zero, full name (e.g. "net/ipv4/tcp_mem") is
4023	* copied. Use BPF_F_SYSCTL_BASE_NAME flag to copy base name
4024	* only (e.g. "tcp_mem").
4025	* Return
4026	* Number of character copied (not including the trailing NUL).
4027	*
4028	* -E2BIG if the buffer wasn't big enough (buf will contain
4029	* truncated name in this case).
4030	*
4031	* long bpf_sysctl_get_current_value(struct bpf_sysctl ctx, char buf, size_t buf_len)
4032	* Description
4033	* Get current value of sysctl as it is presented in /proc/sys
4034	* (incl. newline, etc), and copy it as a string into provided
4035	* by program buffer buf of size buf_len.
4036	*
4037	* The whole value is copied, no matter what file position user
4038	* space issued e.g. sys_read at.
4039	*
4040	* The buffer is always NUL terminated, unless it's zero-sized.
4041	* Return
4042	* Number of character copied (not including the trailing NUL).
4043	*
4044	* -E2BIG if the buffer wasn't big enough (buf will contain
4045	* truncated name in this case).
4046	*
4047	* -EINVAL if current value was unavailable, e.g. because
4048	* sysctl is uninitialized and read returns -EIO for it.
4049	*
4050	* long bpf_sysctl_get_new_value(struct bpf_sysctl ctx, char buf, size_t buf_len)
4051	* Description
4052	* Get new value being written by user space to sysctl (before
4053	* the actual write happens) and copy it as a string into
4054	* provided by program buffer buf of size buf_len.
4055	*
4056	* User space may write new value at file position > 0.
4057	*
4058	* The buffer is always NUL terminated, unless it's zero-sized.
4059	* Return
4060	* Number of character copied (not including the trailing NUL).
4061	*
4062	* -E2BIG if the buffer wasn't big enough (buf will contain
4063	* truncated name in this case).
4064	*
4065	* -EINVAL if sysctl is being read.
4066	*
4067	* long bpf_sysctl_set_new_value(struct bpf_sysctl ctx, const char buf, size_t buf_len)
4068	* Description
4069	* Override new value being written by user space to sysctl with
4070	* value provided by program in buffer buf of size buf_len.
4071	*
4072	* buf should contain a string in same form as provided by user
4073	* space on sysctl write.
4074	*
4075	* User space may write new value at file position > 0. To override
4076	* the whole sysctl value file position should be set to zero.
4077	* Return
4078	* 0 on success.
4079	*
4080	* -E2BIG if the buf_len is too big.
4081	*
4082	* -EINVAL if sysctl is being read.
4083	*
4084	* long bpf_strtol(const char buf, size_t buf_len, u64 flags, long res)
4085	* Description
4086	* Convert the initial part of the string from buffer buf of
4087	* size buf_len to a long integer according to the given base
4088	* and save the result in res.
4089	*
4090	* The string may begin with an arbitrary amount of white space
4091	* (as determined by isspace\ (3)) followed by a single
4092	* optional '-' sign.
4093	*
4094	* Five least significant bits of flags encode base, other bits
4095	* are currently unused.
4096	*
4097	* Base must be either 8, 10, 16 or 0 to detect it automatically
4098	* similar to user space strtol\ (3).
4099	* Return
4100	* Number of characters consumed on success. Must be positive but
4101	* no more than buf_len.
4102	*
4103	* -EINVAL if no valid digits were found or unsupported base
4104	* was provided.
4105	*
4106	* -ERANGE if resulting value was out of range.
4107	*
4108	* long bpf_strtoul(const char buf, size_t buf_len, u64 flags, unsigned long res)
4109	* Description
4110	* Convert the initial part of the string from buffer buf of
4111	* size buf_len to an unsigned long integer according to the
4112	* given base and save the result in res.
4113	*
4114	* The string may begin with an arbitrary amount of white space
4115	* (as determined by isspace\ (3)).
4116	*
4117	* Five least significant bits of flags encode base, other bits
4118	* are currently unused.
4119	*
4120	* Base must be either 8, 10, 16 or 0 to detect it automatically
4121	* similar to user space strtoul\ (3).
4122	* Return
4123	* Number of characters consumed on success. Must be positive but
4124	* no more than buf_len.
4125	*
4126	* -EINVAL if no valid digits were found or unsupported base
4127	* was provided.
4128	*
4129	* -ERANGE if resulting value was out of range.
4130	*
4131	* void bpf_sk_storage_get(struct bpf_map map, void sk, void value, u64 flags)
4132	* Description
4133	* Get a bpf-local-storage from a sk.
4134	*
4135	* Logically, it could be thought of getting the value from
4136	* a map with sk as the key. From this
4137	* perspective, the usage is not much different from
4138	* bpf_map_lookup_elem\ (map, &\ sk) except this
4139	* helper enforces the key must be a full socket and the map must
4140	* be a BPF_MAP_TYPE_SK_STORAGE also.
4141	*
4142	* Underneath, the value is stored locally at sk instead of
4143	* the map. The map is used as the bpf-local-storage
4144	* "type". The bpf-local-storage "type" (i.e. the map) is
4145	* searched against all bpf-local-storages residing at sk.
4146	*
4147	* sk is a kernel struct sock pointer for LSM program.
4148	* sk is a struct bpf_sock pointer for other program types.
4149	*
4150	* An optional flags (BPF_SK_STORAGE_GET_F_CREATE) can be
4151	* used such that a new bpf-local-storage will be
4152	* created if one does not exist. value can be used
4153	* together with BPF_SK_STORAGE_GET_F_CREATE to specify
4154	* the initial value of a bpf-local-storage. If value is
4155	* NULL, the new bpf-local-storage will be zero initialized.
4156	* Return
4157	* A bpf-local-storage pointer is returned on success.
4158	*
4159	* NULL if not found or there was an error in adding
4160	* a new bpf-local-storage.
4161	*
4162	* long bpf_sk_storage_delete(struct bpf_map map, void sk)
4163	* Description
4164	* Delete a bpf-local-storage from a sk.
4165	* Return
4166	* 0 on success.
4167	*
4168	* -ENOENT if the bpf-local-storage cannot be found.
4169	* -EINVAL if sk is not a fullsock (e.g. a request_sock).
4170	*
4171	* long bpf_send_signal(u32 sig)
4172	* Description
4173	* Send signal sig to the process of the current task.
4174	* The signal may be delivered to any of this process's threads.
4175	* Return
4176	* 0 on success or successfully queued.
4177	*
4178	* -EBUSY if work queue under nmi is full.
4179	*
4180	* -EINVAL if sig is invalid.
4181	*
4182	* -EPERM if no permission to send the sig.
4183	*
4184	* -EAGAIN if bpf program can try again.
4185	*
4186	* s64 bpf_tcp_gen_syncookie(void sk, void iph, u32 iph_len, struct tcphdr *th, u32 th_len)
4187	* Description
4188	* Try to issue a SYN cookie for the packet with corresponding
4189	* IP/TCP headers, iph and th, on the listening socket in sk.
4190	*
4191	* iph points to the start of the IPv4 or IPv6 header, while
4192	* iph_len contains sizeof\ (struct iphdr) or
4193	* sizeof\ (struct ipv6hdr).
4194	*
4195	* th points to the start of the TCP header, while th_len
4196	* contains the length of the TCP header with options (at least
4197	* sizeof\ (struct tcphdr)).
4198	* Return
4199	* On success, lower 32 bits hold the generated SYN cookie in
4200	* followed by 16 bits which hold the MSS value for that cookie,
4201	* and the top 16 bits are unused.
4202	*
4203	* On failure, the returned value is one of the following:
4204	*
4205	* -EINVAL SYN cookie cannot be issued due to error
4206	*
4207	* -ENOENT SYN cookie should not be issued (no SYN flood)
4208	*
4209	* -EOPNOTSUPP kernel configuration does not enable SYN cookies
4210	*
4211	* -EPROTONOSUPPORT IP packet version is not 4 or 6
4212	*
4213	* long bpf_skb_output(void ctx, struct bpf_map map, u64 flags, void *data, u64 size)
4214	* Description
4215	* Write raw data blob into a special BPF perf event held by
4216	* map of type BPF_MAP_TYPE_PERF_EVENT_ARRAY. This perf
4217	* event must have the following attributes: PERF_SAMPLE_RAW
4218	* as sample_type, PERF_TYPE_SOFTWARE as type, and
4219	* PERF_COUNT_SW_BPF_OUTPUT as config.
4220	*
4221	* The flags are used to indicate the index in map for which
4222	* the value must be put, masked with BPF_F_INDEX_MASK.
4223	* Alternatively, flags can be set to BPF_F_CURRENT_CPU
4224	* to indicate that the index of the current CPU core should be
4225	* used.
4226	*
4227	* The value to write, of size, is passed through eBPF stack and
4228	* pointed by data.
4229	*
4230	* ctx is a pointer to in-kernel struct sk_buff.
4231	*
4232	* This helper is similar to bpf_perf_event_output\ () but
4233	* restricted to raw_tracepoint bpf programs.
4234	* Return
4235	* 0 on success, or a negative error in case of failure.
4236	*
4237	* long bpf_probe_read_user(void dst, u32 size, const void unsafe_ptr)
4238	* Description
4239	* Safely attempt to read size bytes from user space address
4240	* unsafe_ptr and store the data in dst.
4241	* Return
4242	* 0 on success, or a negative error in case of failure.
4243	*
4244	* long bpf_probe_read_kernel(void dst, u32 size, const void unsafe_ptr)
4245	* Description
4246	* Safely attempt to read size bytes from kernel space address
4247	* unsafe_ptr and store the data in dst.
4248	* Return
4249	* 0 on success, or a negative error in case of failure.
4250	*
4251	* long bpf_probe_read_user_str(void dst, u32 size, const void unsafe_ptr)
4252	* Description
4253	* Copy a NUL terminated string from an unsafe user address
4254	* unsafe_ptr to dst. The size should include the
4255	* terminating NUL byte. In case the string length is smaller than
4256	* size, the target is not padded with further NUL bytes. If the
4257	* string length is larger than size, just size-1 bytes are
4258	* copied and the last byte is set to NUL.
4259	*
4260	* On success, returns the number of bytes that were written,
4261	* including the terminal NUL. This makes this helper useful in
4262	* tracing programs for reading strings, and more importantly to
4263	* get its length at runtime. See the following snippet:
4264	*
4265	* ::
4266	*
4267	* SEC("kprobe/sys_open")
4268	* void bpf_sys_open(struct pt_regs *ctx)
4269	* {
4270	* char buf[PATHLEN]; // PATHLEN is defined to 256
4271	* int res = bpf_probe_read_user_str(buf, sizeof(buf),
4272	* ctx->di);
4273	*
4274	* // Consume buf, for example push it to
4275	* // userspace via bpf_perf_event_output(); we
4276	* // can use res (the string length) as event
4277	* // size, after checking its boundaries.
4278	* }
4279	*
4280	* In comparison, using bpf_probe_read_user\ () helper here
4281	* instead to read the string would require to estimate the length
4282	* at compile time, and would often result in copying more memory
4283	* than necessary.
4284	*
4285	* Another useful use case is when parsing individual process
4286	* arguments or individual environment variables navigating
4287	* current\ ->mm->arg_start and current\
4288	* ->mm->env_start: using this helper and the return value,
4289	* one can quickly iterate at the right offset of the memory area.
4290	* Return
4291	* On success, the strictly positive length of the output string,
4292	* including the trailing NUL character. On error, a negative
4293	* value.
4294	*
4295	* long bpf_probe_read_kernel_str(void dst, u32 size, const void unsafe_ptr)
4296	* Description
4297	* Copy a NUL terminated string from an unsafe kernel address unsafe_ptr
4298	* to dst. Same semantics as with bpf_probe_read_user_str\ () apply.
4299	* Return
4300	* On success, the strictly positive length of the string, including
4301	* the trailing NUL character. On error, a negative value.
4302	*
4303	* long bpf_tcp_send_ack(void *tp, u32 rcv_nxt)
4304	* Description
4305	* Send out a tcp-ack. tp is the in-kernel struct tcp_sock.
4306	* rcv_nxt is the ack_seq to be sent out.
4307	* Return
4308	* 0 on success, or a negative error in case of failure.
4309	*
4310	* long bpf_send_signal_thread(u32 sig)
4311	* Description
4312	* Send signal sig to the thread corresponding to the current task.
4313	* Return
4314	* 0 on success or successfully queued.
4315	*
4316	* -EBUSY if work queue under nmi is full.
4317	*
4318	* -EINVAL if sig is invalid.
4319	*
4320	* -EPERM if no permission to send the sig.
4321	*
4322	* -EAGAIN if bpf program can try again.
4323	*
4324	* u64 bpf_jiffies64(void)
4325	* Description
4326	* Obtain the 64bit jiffies
4327	* Return
4328	* The 64 bit jiffies
4329	*
4330	* long bpf_read_branch_records(struct bpf_perf_event_data ctx, void buf, u32 size, u64 flags)
4331	* Description
4332	* For an eBPF program attached to a perf event, retrieve the
4333	* branch records (struct perf_branch_entry) associated to ctx
4334	* and store it in the buffer pointed by buf up to size
4335	* size bytes.
4336	* Return
4337	* On success, number of bytes written to buf. On error, a
4338	* negative value.
4339	*
4340	* The flags can be set to BPF_F_GET_BRANCH_RECORDS_SIZE to
4341	* instead return the number of bytes required to store all the
4342	* branch entries. If this flag is set, buf may be NULL.
4343	*
4344	* -EINVAL if arguments invalid or size not a multiple
4345	* of sizeof\ (struct perf_branch_entry\ ).
4346	*
4347	* -ENOENT if architecture does not support branch records.
4348	*
4349	* long bpf_get_ns_current_pid_tgid(u64 dev, u64 ino, struct bpf_pidns_info *nsdata, u32 size)
4350	* Description
4351	* Returns 0 on success, values for pid and tgid as seen from the current
4352	* namespace will be returned in nsdata.
4353	* Return
4354	* 0 on success, or one of the following in case of failure:
4355	*
4356	* -EINVAL if dev and inum supplied don't match dev_t and inode number
4357	* with nsfs of current task, or if dev conversion to dev_t lost high bits.
4358	*
4359	* -ENOENT if pidns does not exists for the current task.
4360	*
4361	* long bpf_xdp_output(void ctx, struct bpf_map map, u64 flags, void *data, u64 size)
4362	* Description
4363	* Write raw data blob into a special BPF perf event held by
4364	* map of type BPF_MAP_TYPE_PERF_EVENT_ARRAY. This perf
4365	* event must have the following attributes: PERF_SAMPLE_RAW
4366	* as sample_type, PERF_TYPE_SOFTWARE as type, and
4367	* PERF_COUNT_SW_BPF_OUTPUT as config.
4368	*
4369	* The flags are used to indicate the index in map for which
4370	* the value must be put, masked with BPF_F_INDEX_MASK.
4371	* Alternatively, flags can be set to BPF_F_CURRENT_CPU
4372	* to indicate that the index of the current CPU core should be
4373	* used.
4374	*
4375	* The value to write, of size, is passed through eBPF stack and
4376	* pointed by data.
4377	*
4378	* ctx is a pointer to in-kernel struct xdp_buff.
4379	*
4380	* This helper is similar to bpf_perf_eventoutput\ () but
4381	* restricted to raw_tracepoint bpf programs.
4382	* Return
4383	* 0 on success, or a negative error in case of failure.
4384	*
4385	* u64 bpf_get_netns_cookie(void *ctx)
4386	* Description
4387	* Retrieve the cookie (generated by the kernel) of the network
4388	* namespace the input ctx is associated with. The network
4389	* namespace cookie remains stable for its lifetime and provides
4390	* a global identifier that can be assumed unique. If ctx is
4391	* NULL, then the helper returns the cookie for the initial
4392	* network namespace. The cookie itself is very similar to that
4393	* of bpf_get_socket_cookie\ () helper, but for network
4394	* namespaces instead of sockets.
4395	* Return
4396	* A 8-byte long opaque number.
4397	*
4398	* u64 bpf_get_current_ancestor_cgroup_id(int ancestor_level)
4399	* Description
4400	* Return id of cgroup v2 that is ancestor of the cgroup associated
4401	* with the current task at the ancestor_level. The root cgroup
4402	* is at ancestor_level zero and each step down the hierarchy
4403	* increments the level. If ancestor_level == level of cgroup
4404	* associated with the current task, then return value will be the
4405	* same as that of bpf_get_current_cgroup_id\ ().
4406	*
4407	* The helper is useful to implement policies based on cgroups
4408	* that are upper in hierarchy than immediate cgroup associated
4409	* with the current task.
4410	*
4411	* The format of returned id and helper limitations are same as in
4412	* bpf_get_current_cgroup_id\ ().
4413	* Return
4414	* The id is returned or 0 in case the id could not be retrieved.
4415	*
4416	* long bpf_sk_assign(struct sk_buff skb, void sk, u64 flags)
4417	* Description
4418	* Helper is overloaded depending on BPF program type. This
4419	* description applies to BPF_PROG_TYPE_SCHED_CLS and
4420	* BPF_PROG_TYPE_SCHED_ACT programs.
4421	*
4422	* Assign the sk to the skb. When combined with appropriate
4423	* routing configuration to receive the packet towards the socket,
4424	* will cause skb to be delivered to the specified socket.
4425	* Subsequent redirection of skb via bpf_redirect\ (),
4426	* bpf_clone_redirect\ () or other methods outside of BPF may
4427	* interfere with successful delivery to the socket.
4428	*
4429	* This operation is only valid from TC ingress path.
4430	*
4431	* The flags argument must be zero.
4432	* Return
4433	* 0 on success, or a negative error in case of failure:
4434	*
4435	* -EINVAL if specified flags are not supported.
4436	*
4437	* -ENOENT if the socket is unavailable for assignment.
4438	*
4439	* -ENETUNREACH if the socket is unreachable (wrong netns).
4440	*
4441	* -EOPNOTSUPP if the operation is not supported, for example
4442	* a call from outside of TC ingress.
4443	*
4444	* long bpf_sk_assign(struct bpf_sk_lookup ctx, struct bpf_sock sk, u64 flags)
4445	* Description
4446	* Helper is overloaded depending on BPF program type. This
4447	* description applies to BPF_PROG_TYPE_SK_LOOKUP programs.
4448	*
4449	* Select the sk as a result of a socket lookup.
4450	*
4451	* For the operation to succeed passed socket must be compatible
4452	* with the packet description provided by the ctx object.
4453	*
4454	* L4 protocol (IPPROTO_TCP or IPPROTO_UDP) must
4455	* be an exact match. While IP family (AF_INET or
4456	* AF_INET6) must be compatible, that is IPv6 sockets
4457	* that are not v6-only can be selected for IPv4 packets.
4458	*
4459	* Only TCP listeners and UDP unconnected sockets can be
4460	* selected. sk can also be NULL to reset any previous
4461	* selection.
4462	*
4463	* flags argument can combination of following values:
4464	*
4465	* * BPF_SK_LOOKUP_F_REPLACE to override the previous
4466	* socket selection, potentially done by a BPF program
4467	* that ran before us.
4468	*
4469	* * BPF_SK_LOOKUP_F_NO_REUSEPORT to skip
4470	* load-balancing within reuseport group for the socket
4471	* being selected.
4472	*
4473	* On success ctx->sk will point to the selected socket.
4474	*
4475	* Return
4476	* 0 on success, or a negative errno in case of failure.
4477	*
4478	* * -EAFNOSUPPORT if socket family (sk->family) is
4479	* not compatible with packet family (ctx->family).
4480	*
4481	* * -EEXIST if socket has been already selected,
4482	* potentially by another program, and
4483	* BPF_SK_LOOKUP_F_REPLACE flag was not specified.
4484	*
4485	* * -EINVAL if unsupported flags were specified.
4486	*
4487	* * -EPROTOTYPE if socket L4 protocol
4488	* (sk->protocol) doesn't match packet protocol
4489	* (ctx->protocol).
4490	*
4491	* * -ESOCKTNOSUPPORT if socket is not in allowed
4492	* state (TCP listening or UDP unconnected).
4493	*
4494	* u64 bpf_ktime_get_boot_ns(void)
4495	* Description
4496	* Return the time elapsed since system boot, in nanoseconds.
4497	* Does include the time the system was suspended.
4498	* See: clock_gettime\ (CLOCK_BOOTTIME)
4499	* Return
4500	* Current ktime.
4501	*
4502	* long bpf_seq_printf(struct seq_file m, const char fmt, u32 fmt_size, const void *data, u32 data_len)
4503	* Description
4504	* bpf_seq_printf\ () uses seq_file seq_printf\ () to print
4505	* out the format string.
4506	* The m represents the seq_file. The fmt and fmt_size are for
4507	* the format string itself. The data and data_len are format string
4508	* arguments. The data are a u64 array and corresponding format string
4509	* values are stored in the array. For strings and pointers where pointees
4510	* are accessed, only the pointer values are stored in the data array.
4511	* The data_len is the size of data in bytes - must be a multiple of 8.
4512	*
4513	* Formats %s, %p{i,I}{4,6} requires to read kernel memory.
4514	* Reading kernel memory may fail due to either invalid address or
4515	* valid address but requiring a major memory fault. If reading kernel memory
4516	* fails, the string for %s will be an empty string, and the ip
4517	* address for %p{i,I}{4,6} will be 0. Not returning error to
4518	* bpf program is consistent with what bpf_trace_printk\ () does for now.
4519	* Return
4520	* 0 on success, or a negative error in case of failure:
4521	*
4522	* -EBUSY if per-CPU memory copy buffer is busy, can try again
4523	* by returning 1 from bpf program.
4524	*
4525	* -EINVAL if arguments are invalid, or if fmt is invalid/unsupported.
4526	*
4527	* -E2BIG if fmt contains too many format specifiers.
4528	*
4529	* -EOVERFLOW if an overflow happened: The same object will be tried again.
4530	*
4531	* long bpf_seq_write(struct seq_file m, const void data, u32 len)
4532	* Description
4533	* bpf_seq_write\ () uses seq_file seq_write\ () to write the data.
4534	* The m represents the seq_file. The data and len represent the
4535	* data to write in bytes.
4536	* Return
4537	* 0 on success, or a negative error in case of failure:
4538	*
4539	* -EOVERFLOW if an overflow happened: The same object will be tried again.
4540	*
4541	* u64 bpf_sk_cgroup_id(void *sk)
4542	* Description
4543	* Return the cgroup v2 id of the socket sk.
4544	*
4545	* sk must be a non-NULL pointer to a socket, e.g. one
4546	* returned from bpf_sk_lookup_xxx\ (),
4547	* bpf_sk_fullsock\ (), etc. The format of returned id is
4548	* same as in bpf_skb_cgroup_id\ ().
4549	*
4550	* This helper is available only if the kernel was compiled with
4551	* the CONFIG_SOCK_CGROUP_DATA configuration option.
4552	* Return
4553	* The id is returned or 0 in case the id could not be retrieved.
4554	*
4555	* u64 bpf_sk_ancestor_cgroup_id(void *sk, int ancestor_level)
4556	* Description
4557	* Return id of cgroup v2 that is ancestor of cgroup associated
4558	* with the sk at the ancestor_level. The root cgroup is at
4559	* ancestor_level zero and each step down the hierarchy
4560	* increments the level. If ancestor_level == level of cgroup
4561	* associated with sk, then return value will be same as that
4562	* of bpf_sk_cgroup_id\ ().
4563	*
4564	* The helper is useful to implement policies based on cgroups
4565	* that are upper in hierarchy than immediate cgroup associated
4566	* with sk.
4567	*
4568	* The format of returned id and helper limitations are same as in
4569	* bpf_sk_cgroup_id\ ().
4570	* Return
4571	* The id is returned or 0 in case the id could not be retrieved.
4572	*
4573	* long bpf_ringbuf_output(void ringbuf, void data, u64 size, u64 flags)
4574	* Description
4575	* Copy size bytes from data into a ring buffer ringbuf.
4576	* If BPF_RB_NO_WAKEUP is specified in flags, no notification
4577	* of new data availability is sent.
4578	* If BPF_RB_FORCE_WAKEUP is specified in flags, notification
4579	* of new data availability is sent unconditionally.
4580	* If 0 is specified in flags, an adaptive notification
4581	* of new data availability is sent.
4582	*
4583	* An adaptive notification is a notification sent whenever the user-space
4584	* process has caught up and consumed all available payloads. In case the user-space
4585	* process is still processing a previous payload, then no notification is needed
4586	* as it will process the newly added payload automatically.
4587	* Return
4588	* 0 on success, or a negative error in case of failure.
4589	*
4590	* void bpf_ringbuf_reserve(void ringbuf, u64 size, u64 flags)
4591	* Description
4592	* Reserve size bytes of payload in a ring buffer ringbuf.
4593	* flags must be 0.
4594	* Return
4595	* Valid pointer with size bytes of memory available; NULL,
4596	* otherwise.
4597	*
4598	* void bpf_ringbuf_submit(void *data, u64 flags)
4599	* Description
4600	* Submit reserved ring buffer sample, pointed to by data.
4601	* If BPF_RB_NO_WAKEUP is specified in flags, no notification
4602	* of new data availability is sent.
4603	* If BPF_RB_FORCE_WAKEUP is specified in flags, notification
4604	* of new data availability is sent unconditionally.
4605	* If 0 is specified in flags, an adaptive notification
4606	* of new data availability is sent.
4607	*
4608	* See 'bpf_ringbuf_output()' for the definition of adaptive notification.
4609	* Return
4610	* Nothing. Always succeeds.
4611	*
4612	* void bpf_ringbuf_discard(void *data, u64 flags)
4613	* Description
4614	* Discard reserved ring buffer sample, pointed to by data.
4615	* If BPF_RB_NO_WAKEUP is specified in flags, no notification
4616	* of new data availability is sent.
4617	* If BPF_RB_FORCE_WAKEUP is specified in flags, notification
4618	* of new data availability is sent unconditionally.
4619	* If 0 is specified in flags, an adaptive notification
4620	* of new data availability is sent.
4621	*
4622	* See 'bpf_ringbuf_output()' for the definition of adaptive notification.
4623	* Return
4624	* Nothing. Always succeeds.
4625	*
4626	* u64 bpf_ringbuf_query(void *ringbuf, u64 flags)
4627	* Description
4628	* Query various characteristics of provided ring buffer. What
4629	* exactly is queries is determined by flags:
4630	*
4631	* * BPF_RB_AVAIL_DATA: Amount of data not yet consumed.
4632	* * BPF_RB_RING_SIZE: The size of ring buffer.
4633	* * BPF_RB_CONS_POS: Consumer position (can wrap around).
4634	* * BPF_RB_PROD_POS: Producer(s) position (can wrap around).
4635	*
4636	* Data returned is just a momentary snapshot of actual values
4637	* and could be inaccurate, so this facility should be used to
4638	* power heuristics and for reporting, not to make 100% correct
4639	* calculation.
4640	* Return
4641	* Requested value, or 0, if flags are not recognized.
4642	*
4643	* long bpf_csum_level(struct sk_buff *skb, u64 level)
4644	* Description
4645	* Change the skbs checksum level by one layer up or down, or
4646	* reset it entirely to none in order to have the stack perform
4647	* checksum validation. The level is applicable to the following
4648	* protocols: TCP, UDP, GRE, SCTP, FCOE. For example, a decap of
4649	* \| ETH \| IP \| UDP \| GUE \| IP \| TCP \| into \| ETH \| IP \| TCP \|
4650	* through bpf_skb_adjust_room\ () helper with passing in
4651	* BPF_F_ADJ_ROOM_NO_CSUM_RESET flag would require one call
4652	* to bpf_csum_level\ () with BPF_CSUM_LEVEL_DEC since
4653	* the UDP header is removed. Similarly, an encap of the latter
4654	* into the former could be accompanied by a helper call to
4655	* bpf_csum_level\ () with BPF_CSUM_LEVEL_INC if the
4656	* skb is still intended to be processed in higher layers of the
4657	* stack instead of just egressing at tc.
4658	*
4659	* There are three supported level settings at this time:
4660	*
4661	* * BPF_CSUM_LEVEL_INC: Increases skb->csum_level for skbs
4662	* with CHECKSUM_UNNECESSARY.
4663	* * BPF_CSUM_LEVEL_DEC: Decreases skb->csum_level for skbs
4664	* with CHECKSUM_UNNECESSARY.
4665	* * BPF_CSUM_LEVEL_RESET: Resets skb->csum_level to 0 and
4666	* sets CHECKSUM_NONE to force checksum validation by the stack.
4667	* * BPF_CSUM_LEVEL_QUERY: No-op, returns the current
4668	* skb->csum_level.
4669	* Return
4670	* 0 on success, or a negative error in case of failure. In the
4671	* case of BPF_CSUM_LEVEL_QUERY, the current skb->csum_level
4672	* is returned or the error code -EACCES in case the skb is not
4673	* subject to CHECKSUM_UNNECESSARY.
4674	*
4675	* struct tcp6_sock bpf_skc_to_tcp6_sock(void sk)
4676	* Description
4677	* Dynamically cast a sk pointer to a tcp6_sock pointer.
4678	* Return
4679	* sk if casting is valid, or NULL otherwise.
4680	*
4681	* struct tcp_sock bpf_skc_to_tcp_sock(void sk)
4682	* Description
4683	* Dynamically cast a sk pointer to a tcp_sock pointer.
4684	* Return
4685	* sk if casting is valid, or NULL otherwise.
4686	*
4687	* struct tcp_timewait_sock bpf_skc_to_tcp_timewait_sock(void sk)
4688	* Description
4689	* Dynamically cast a sk pointer to a tcp_timewait_sock pointer.
4690	* Return
4691	* sk if casting is valid, or NULL otherwise.
4692	*
4693	* struct tcp_request_sock bpf_skc_to_tcp_request_sock(void sk)
4694	* Description
4695	* Dynamically cast a sk pointer to a tcp_request_sock pointer.
4696	* Return
4697	* sk if casting is valid, or NULL otherwise.
4698	*
4699	* struct udp6_sock bpf_skc_to_udp6_sock(void sk)
4700	* Description
4701	* Dynamically cast a sk pointer to a udp6_sock pointer.
4702	* Return
4703	* sk if casting is valid, or NULL otherwise.
4704	*
4705	* long bpf_get_task_stack(struct task_struct task, void buf, u32 size, u64 flags)
4706	* Description
4707	* Return a user or a kernel stack in bpf program provided buffer.
4708	* Note: the user stack will only be populated if the task is
4709	* the current task; all other tasks will return -EOPNOTSUPP.
4710	* To achieve this, the helper needs task, which is a valid
4711	* pointer to struct task_struct. To store the stacktrace, the
4712	* bpf program provides buf with a nonnegative size.
4713	*
4714	* The last argument, flags, holds the number of stack frames to
4715	* skip (from 0 to 255), masked with
4716	* BPF_F_SKIP_FIELD_MASK. The next bits can be used to set
4717	* the following flags:
4718	*
4719	* BPF_F_USER_STACK
4720	* Collect a user space stack instead of a kernel stack.
4721	* The task must be the current task.
4722	* BPF_F_USER_BUILD_ID
4723	* Collect buildid+offset instead of ips for user stack,
4724	* only valid if BPF_F_USER_STACK is also specified.
4725	*
4726	* bpf_get_task_stack\ () can collect up to
4727	* PERF_MAX_STACK_DEPTH both kernel and user frames, subject
4728	* to sufficient large buffer size. Note that
4729	* this limit can be controlled with the sysctl program, and
4730	* that it should be manually increased in order to profile long
4731	* user stacks (such as stacks for Java programs). To do so, use:
4732	*
4733	* ::
4734	*
4735	* # sysctl kernel.perf_event_max_stack=<new value>
4736	* Return
4737	* The non-negative copied buf length equal to or less than
4738	* size on success, or a negative error in case of failure.
4739	*
4740	* long bpf_load_hdr_opt(struct bpf_sock_ops skops, void searchby_res, u32 len, u64 flags)
4741	* Description
4742	* Load header option. Support reading a particular TCP header
4743	* option for bpf program (BPF_PROG_TYPE_SOCK_OPS).
4744	*
4745	* If flags is 0, it will search the option from the
4746	* skops\ ->skb_data. The comment in struct bpf_sock_ops
4747	* has details on what skb_data contains under different
4748	* skops\ ->op.
4749	*
4750	* The first byte of the searchby_res specifies the
4751	* kind that it wants to search.
4752	*
4753	* If the searching kind is an experimental kind
4754	* (i.e. 253 or 254 according to RFC6994). It also
4755	* needs to specify the "magic" which is either
4756	* 2 bytes or 4 bytes. It then also needs to
4757	* specify the size of the magic by using
4758	* the 2nd byte which is "kind-length" of a TCP
4759	* header option and the "kind-length" also
4760	* includes the first 2 bytes "kind" and "kind-length"
4761	* itself as a normal TCP header option also does.
4762	*
4763	* For example, to search experimental kind 254 with
4764	* 2 byte magic 0xeB9F, the searchby_res should be
4765	* [ 254, 4, 0xeB, 0x9F, 0, 0, .... 0 ].
4766	*
4767	* To search for the standard window scale option (3),
4768	* the searchby_res should be [ 3, 0, 0, .... 0 ].
4769	* Note, kind-length must be 0 for regular option.
4770	*
4771	* Searching for No-Op (0) and End-of-Option-List (1) are
4772	* not supported.
4773	*
4774	* len must be at least 2 bytes which is the minimal size
4775	* of a header option.
4776	*
4777	* Supported flags:
4778	*
4779	* * BPF_LOAD_HDR_OPT_TCP_SYN to search from the
4780	* saved_syn packet or the just-received syn packet.
4781	*
4782	* Return
4783	* > 0 when found, the header option is copied to searchby_res.
4784	* The return value is the total length copied. On failure, a
4785	* negative error code is returned:
4786	*
4787	* -EINVAL if a parameter is invalid.
4788	*
4789	* -ENOMSG if the option is not found.
4790	*
4791	* -ENOENT if no syn packet is available when
4792	* BPF_LOAD_HDR_OPT_TCP_SYN is used.
4793	*
4794	* -ENOSPC if there is not enough space. Only len number of
4795	* bytes are copied.
4796	*
4797	* -EFAULT on failure to parse the header options in the
4798	* packet.
4799	*
4800	* -EPERM if the helper cannot be used under the current
4801	* skops\ ->op.
4802	*
4803	* long bpf_store_hdr_opt(struct bpf_sock_ops skops, const void from, u32 len, u64 flags)
4804	* Description
4805	* Store header option. The data will be copied
4806	* from buffer from with length len to the TCP header.
4807	*
4808	* The buffer from should have the whole option that
4809	* includes the kind, kind-length, and the actual
4810	* option data. The len must be at least kind-length
4811	* long. The kind-length does not have to be 4 byte
4812	* aligned. The kernel will take care of the padding
4813	* and setting the 4 bytes aligned value to th->doff.
4814	*
4815	* This helper will check for duplicated option
4816	* by searching the same option in the outgoing skb.
4817	*
4818	* This helper can only be called during
4819	* BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
4820	*
4821	* Return
4822	* 0 on success, or negative error in case of failure:
4823	*
4824	* -EINVAL If param is invalid.
4825	*
4826	* -ENOSPC if there is not enough space in the header.
4827	* Nothing has been written
4828	*
4829	* -EEXIST if the option already exists.
4830	*
4831	* -EFAULT on failure to parse the existing header options.
4832	*
4833	* -EPERM if the helper cannot be used under the current
4834	* skops\ ->op.
4835	*
4836	* long bpf_reserve_hdr_opt(struct bpf_sock_ops *skops, u32 len, u64 flags)
4837	* Description
4838	* Reserve len bytes for the bpf header option. The
4839	* space will be used by bpf_store_hdr_opt\ () later in
4840	* BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
4841	*
4842	* If bpf_reserve_hdr_opt\ () is called multiple times,
4843	* the total number of bytes will be reserved.
4844	*
4845	* This helper can only be called during
4846	* BPF_SOCK_OPS_HDR_OPT_LEN_CB.
4847	*
4848	* Return
4849	* 0 on success, or negative error in case of failure:
4850	*
4851	* -EINVAL if a parameter is invalid.
4852	*
4853	* -ENOSPC if there is not enough space in the header.
4854	*
4855	* -EPERM if the helper cannot be used under the current
4856	* skops\ ->op.
4857	*
4858	* void bpf_inode_storage_get(struct bpf_map map, void inode, void value, u64 flags)
4859	* Description
4860	* Get a bpf_local_storage from an inode.
4861	*
4862	* Logically, it could be thought of as getting the value from
4863	* a map with inode as the key. From this
4864	* perspective, the usage is not much different from
4865	* bpf_map_lookup_elem\ (map, &\ inode) except this
4866	* helper enforces the key must be an inode and the map must also
4867	* be a BPF_MAP_TYPE_INODE_STORAGE.
4868	*
4869	* Underneath, the value is stored locally at inode instead of
4870	* the map. The map is used as the bpf-local-storage
4871	* "type". The bpf-local-storage "type" (i.e. the map) is
4872	* searched against all bpf_local_storage residing at inode.
4873	*
4874	* An optional flags (BPF_LOCAL_STORAGE_GET_F_CREATE) can be
4875	* used such that a new bpf_local_storage will be
4876	* created if one does not exist. value can be used
4877	* together with BPF_LOCAL_STORAGE_GET_F_CREATE to specify
4878	* the initial value of a bpf_local_storage. If value is
4879	* NULL, the new bpf_local_storage will be zero initialized.
4880	* Return
4881	* A bpf_local_storage pointer is returned on success.
4882	*
4883	* NULL if not found or there was an error in adding
4884	* a new bpf_local_storage.
4885	*
4886	* int bpf_inode_storage_delete(struct bpf_map map, void inode)
4887	* Description
4888	* Delete a bpf_local_storage from an inode.
4889	* Return
4890	* 0 on success.
4891	*
4892	* -ENOENT if the bpf_local_storage cannot be found.
4893	*
4894	* long bpf_d_path(const struct path path, char buf, u32 sz)
4895	* Description
4896	* Return full path for given struct path object, which
4897	* needs to be the kernel BTF path object. The path is
4898	* returned in the provided buffer buf of size sz and
4899	* is zero terminated.
4900	*
4901	* Return
4902	* On success, the strictly positive length of the string,
4903	* including the trailing NUL character. On error, a negative
4904	* value.
4905	*
4906	* long bpf_copy_from_user(void dst, u32 size, const void user_ptr)
4907	* Description
4908	* Read size bytes from user space address user_ptr and store
4909	* the data in dst. This is a wrapper of copy_from_user\ ().
4910	* Return
4911	* 0 on success, or a negative error in case of failure.
4912	*
4913	* long bpf_snprintf_btf(char str, u32 str_size, struct btf_ptr ptr, u32 btf_ptr_size, u64 flags)
4914	* Description
4915	* Use BTF to store a string representation of ptr->ptr in str,
4916	* using ptr->type_id. This value should specify the type
4917	* that ptr->ptr points to. LLVM __builtin_btf_type_id(type, 1)
4918	* can be used to look up vmlinux BTF type ids. Traversing the
4919	* data structure using BTF, the type information and values are
4920	* stored in the first str_size - 1 bytes of str. Safe copy of
4921	* the pointer data is carried out to avoid kernel crashes during
4922	* operation. Smaller types can use string space on the stack;
4923	* larger programs can use map data to store the string
4924	* representation.
4925	*
4926	* The string can be subsequently shared with userspace via
4927	* bpf_perf_event_output() or ring buffer interfaces.
4928	* bpf_trace_printk() is to be avoided as it places too small
4929	* a limit on string size to be useful.
4930	*
4931	* flags is a combination of
4932	*
4933	* BTF_F_COMPACT
4934	* no formatting around type information
4935	* BTF_F_NONAME
4936	* no struct/union member names/types
4937	* BTF_F_PTR_RAW
4938	* show raw (unobfuscated) pointer values;
4939	* equivalent to printk specifier %px.
4940	* BTF_F_ZERO
4941	* show zero-valued struct/union members; they
4942	* are not displayed by default
4943	*
4944	* Return
4945	* The number of bytes that were written (or would have been
4946	* written if output had to be truncated due to string size),
4947	* or a negative error in cases of failure.
4948	*
4949	* long bpf_seq_printf_btf(struct seq_file m, struct btf_ptr ptr, u32 ptr_size, u64 flags)
4950	* Description
4951	* Use BTF to write to seq_write a string representation of
4952	* ptr->ptr, using ptr->type_id as per bpf_snprintf_btf().
4953	* flags are identical to those used for bpf_snprintf_btf.
4954	* Return
4955	* 0 on success or a negative error in case of failure.
4956	*
4957	* u64 bpf_skb_cgroup_classid(struct sk_buff *skb)
4958	* Description
4959	* See bpf_get_cgroup_classid\ () for the main description.
4960	* This helper differs from bpf_get_cgroup_classid\ () in that
4961	* the cgroup v1 net_cls class is retrieved only from the skb's
4962	* associated socket instead of the current process.
4963	* Return
4964	* The id is returned or 0 in case the id could not be retrieved.
4965	*
4966	* long bpf_redirect_neigh(u32 ifindex, struct bpf_redir_neigh *params, int plen, u64 flags)
4967	* Description
4968	* Redirect the packet to another net device of index ifindex
4969	* and fill in L2 addresses from neighboring subsystem. This helper
4970	* is somewhat similar to bpf_redirect\ (), except that it
4971	* populates L2 addresses as well, meaning, internally, the helper
4972	* relies on the neighbor lookup for the L2 address of the nexthop.
4973	*
4974	* The helper will perform a FIB lookup based on the skb's
4975	* networking header to get the address of the next hop, unless
4976	* this is supplied by the caller in the params argument. The
4977	* plen argument indicates the len of params and should be set
4978	* to 0 if params is NULL.
4979	*
4980	* The flags argument is reserved and must be 0. The helper is
4981	* currently only supported for tc BPF program types, and enabled
4982	* for IPv4 and IPv6 protocols.
4983	* Return
4984	* The helper returns TC_ACT_REDIRECT on success or
4985	* TC_ACT_SHOT on error.
4986	*
4987	* void bpf_per_cpu_ptr(const void percpu_ptr, u32 cpu)
4988	* Description
4989	* Take a pointer to a percpu ksym, percpu_ptr, and return a
4990	* pointer to the percpu kernel variable on cpu. A ksym is an
4991	* extern variable decorated with '__ksym'. For ksym, there is a
4992	* global var (either static or global) defined of the same name
4993	* in the kernel. The ksym is percpu if the global var is percpu.
4994	* The returned pointer points to the global percpu var on cpu.
4995	*
4996	* bpf_per_cpu_ptr() has the same semantic as per_cpu_ptr() in the
4997	* kernel, except that bpf_per_cpu_ptr() may return NULL. This
4998	* happens if cpu is larger than nr_cpu_ids. The caller of
4999	* bpf_per_cpu_ptr() must check the returned value.
5000	* Return
5001	* A pointer pointing to the kernel percpu variable on cpu, or
5002	* NULL, if cpu is invalid.
5003	*
5004	* void bpf_this_cpu_ptr(const void percpu_ptr)
5005	* Description
5006	* Take a pointer to a percpu ksym, percpu_ptr, and return a
5007	* pointer to the percpu kernel variable on this cpu. See the
5008	* description of 'ksym' in bpf_per_cpu_ptr\ ().
5009	*
5010	* bpf_this_cpu_ptr() has the same semantic as this_cpu_ptr() in
5011	* the kernel. Different from bpf_per_cpu_ptr\ (), it would
5012	* never return NULL.
5013	* Return
5014	* A pointer pointing to the kernel percpu variable on this cpu.
5015	*
5016	* long bpf_redirect_peer(u32 ifindex, u64 flags)
5017	* Description
5018	* Redirect the packet to another net device of index ifindex.
5019	* This helper is somewhat similar to bpf_redirect\ (), except
5020	* that the redirection happens to the ifindex' peer device and
5021	* the netns switch takes place from ingress to ingress without
5022	* going through the CPU's backlog queue.
5023	*
5024	* skb\ ->mark and skb\ ->tstamp are not cleared during
5025	* the netns switch.
5026	*
5027	* The flags argument is reserved and must be 0. The helper is
5028	* currently only supported for tc BPF program types at the
5029	* ingress hook and for veth and netkit target device types. The
5030	* peer device must reside in a different network namespace.
5031	* Return
5032	* The helper returns TC_ACT_REDIRECT on success or
5033	* TC_ACT_SHOT on error.
5034	*
5035	* void bpf_task_storage_get(struct bpf_map map, struct task_struct task, void value, u64 flags)
5036	* Description
5037	* Get a bpf_local_storage from the task.
5038	*
5039	* Logically, it could be thought of as getting the value from
5040	* a map with task as the key. From this
5041	* perspective, the usage is not much different from
5042	* bpf_map_lookup_elem\ (map, &\ task) except this
5043	* helper enforces the key must be a task_struct and the map must also
5044	* be a BPF_MAP_TYPE_TASK_STORAGE.
5045	*
5046	* Underneath, the value is stored locally at task instead of
5047	* the map. The map is used as the bpf-local-storage
5048	* "type". The bpf-local-storage "type" (i.e. the map) is
5049	* searched against all bpf_local_storage residing at task.
5050	*
5051	* An optional flags (BPF_LOCAL_STORAGE_GET_F_CREATE) can be
5052	* used such that a new bpf_local_storage will be
5053	* created if one does not exist. value can be used
5054	* together with BPF_LOCAL_STORAGE_GET_F_CREATE to specify
5055	* the initial value of a bpf_local_storage. If value is
5056	* NULL, the new bpf_local_storage will be zero initialized.
5057	* Return
5058	* A bpf_local_storage pointer is returned on success.
5059	*
5060	* NULL if not found or there was an error in adding
5061	* a new bpf_local_storage.
5062	*
5063	* long bpf_task_storage_delete(struct bpf_map map, struct task_struct task)
5064	* Description
5065	* Delete a bpf_local_storage from a task.
5066	* Return
5067	* 0 on success.
5068	*
5069	* -ENOENT if the bpf_local_storage cannot be found.
5070	*
5071	* struct task_struct *bpf_get_current_task_btf(void)
5072	* Description
5073	* Return a BTF pointer to the "current" task.
5074	* This pointer can also be used in helpers that accept an
5075	* ARG_PTR_TO_BTF_ID of type task_struct.
5076	* Return
5077	* Pointer to the current task.
5078	*
5079	* long bpf_bprm_opts_set(struct linux_binprm *bprm, u64 flags)
5080	* Description
5081	* Set or clear certain options on bprm:
5082	*
5083	* BPF_F_BPRM_SECUREEXEC Set the secureexec bit
5084	* which sets the AT_SECURE auxv for glibc. The bit
5085	* is cleared if the flag is not specified.
5086	* Return
5087	* -EINVAL if invalid flags are passed, zero otherwise.
5088	*
5089	* u64 bpf_ktime_get_coarse_ns(void)
5090	* Description
5091	* Return a coarse-grained version of the time elapsed since
5092	* system boot, in nanoseconds. Does not include time the system
5093	* was suspended.
5094	*
5095	* See: clock_gettime\ (CLOCK_MONOTONIC_COARSE)
5096	* Return
5097	* Current ktime.
5098	*
5099	* long bpf_ima_inode_hash(struct inode inode, void dst, u32 size)
5100	* Description
5101	* Returns the stored IMA hash of the inode (if it's available).
5102	* If the hash is larger than size, then only size
5103	* bytes will be copied to dst
5104	* Return
5105	* The hash_algo is returned on success,
5106	* -EOPNOTSUPP if IMA is disabled or -EINVAL if
5107	* invalid arguments are passed.
5108	*
5109	* struct socket bpf_sock_from_file(struct file file)
5110	* Description
5111	* If the given file represents a socket, returns the associated
5112	* socket.
5113	* Return
5114	* A pointer to a struct socket on success or NULL if the file is
5115	* not a socket.
5116	*
5117	* long bpf_check_mtu(void ctx, u32 ifindex, u32 mtu_len, s32 len_diff, u64 flags)
5118	* Description
5119	* Check packet size against exceeding MTU of net device (based
5120	* on ifindex). This helper will likely be used in combination
5121	* with helpers that adjust/change the packet size.
5122	*
5123	* The argument len_diff can be used for querying with a planned
5124	* size change. This allows to check MTU prior to changing packet
5125	* ctx. Providing a len_diff adjustment that is larger than the
5126	* actual packet size (resulting in negative packet size) will in
5127	* principle not exceed the MTU, which is why it is not considered
5128	* a failure. Other BPF helpers are needed for performing the
5129	* planned size change; therefore the responsibility for catching
5130	* a negative packet size belongs in those helpers.
5131	*
5132	* Specifying ifindex zero means the MTU check is performed
5133	* against the current net device. This is practical if this isn't
5134	* used prior to redirect.
5135	*
5136	* On input mtu_len must be a valid pointer, else verifier will
5137	* reject BPF program. If the value mtu_len is initialized to
5138	* zero then the ctx packet size is use. When value mtu_len is
5139	* provided as input this specify the L3 length that the MTU check
5140	* is done against. Remember XDP and TC length operate at L2, but
5141	* this value is L3 as this correlate to MTU and IP-header tot_len
5142	* values which are L3 (similar behavior as bpf_fib_lookup).
5143	*
5144	* The Linux kernel route table can configure MTUs on a more
5145	* specific per route level, which is not provided by this helper.
5146	* For route level MTU checks use the bpf_fib_lookup\ ()
5147	* helper.
5148	*
5149	* ctx is either struct xdp_md for XDP programs or
5150	* struct sk_buff for tc cls_act programs.
5151	*
5152	* The flags argument can be a combination of one or more of the
5153	* following values:
5154	*
5155	* BPF_MTU_CHK_SEGS
5156	* This flag will only works for ctx struct sk_buff.
5157	* If packet context contains extra packet segment buffers
5158	* (often knows as GSO skb), then MTU check is harder to
5159	* check at this point, because in transmit path it is
5160	* possible for the skb packet to get re-segmented
5161	* (depending on net device features). This could still be
5162	* a MTU violation, so this flag enables performing MTU
5163	* check against segments, with a different violation
5164	* return code to tell it apart. Check cannot use len_diff.
5165	*
5166	* On return mtu_len pointer contains the MTU value of the net
5167	* device. Remember the net device configured MTU is the L3 size,
5168	* which is returned here and XDP and TC length operate at L2.
5169	* Helper take this into account for you, but remember when using
5170	* MTU value in your BPF-code.
5171	*
5172	* Return
5173	* * 0 on success, and populate MTU value in mtu_len pointer.
5174	*
5175	* * < 0 if any input argument is invalid (mtu_len not updated)
5176	*
5177	* MTU violations return positive values, but also populate MTU
5178	* value in mtu_len pointer, as this can be needed for
5179	* implementing PMTU handing:
5180	*
5181	* * BPF_MTU_CHK_RET_FRAG_NEEDED
5182	* * BPF_MTU_CHK_RET_SEGS_TOOBIG
5183	*
5184	* long bpf_for_each_map_elem(struct bpf_map map, void callback_fn, void *callback_ctx, u64 flags)
5185	* Description
5186	* For each element in map, call callback_fn function with
5187	* map, callback_ctx and other map-specific parameters.
5188	* The callback_fn should be a static function and
5189	* the callback_ctx should be a pointer to the stack.
5190	* The flags is used to control certain aspects of the helper.
5191	* Currently, the flags must be 0.
5192	*
5193	* The following are a list of supported map types and their
5194	* respective expected callback signatures:
5195	*
5196	* BPF_MAP_TYPE_HASH, BPF_MAP_TYPE_PERCPU_HASH,
5197	* BPF_MAP_TYPE_LRU_HASH, BPF_MAP_TYPE_LRU_PERCPU_HASH,
5198	* BPF_MAP_TYPE_ARRAY, BPF_MAP_TYPE_PERCPU_ARRAY
5199	*
5200	* long (\callback_fn)(struct bpf_map \map, const void \key, void \value, void \*ctx);
5201	*
5202	* For per_cpu maps, the map_value is the value on the cpu where the
5203	* bpf_prog is running.
5204	*
5205	* If callback_fn return 0, the helper will continue to the next
5206	* element. If return value is 1, the helper will skip the rest of
5207	* elements and return. Other return values are not used now.
5208	*
5209	* Return
5210	* The number of traversed map elements for success, -EINVAL for
5211	* invalid flags.
5212	*
5213	* long bpf_snprintf(char str, u32 str_size, const char fmt, u64 *data, u32 data_len)
5214	* Description
5215	* Outputs a string into the str buffer of size str_size
5216	* based on a format string stored in a read-only map pointed by
5217	* fmt.
5218	*
5219	* Each format specifier in fmt corresponds to one u64 element
5220	* in the data array. For strings and pointers where pointees
5221	* are accessed, only the pointer values are stored in the data
5222	* array. The data_len is the size of data in bytes - must be
5223	* a multiple of 8.
5224	*
5225	* Formats %s and %p{i,I}{4,6} require to read kernel
5226	* memory. Reading kernel memory may fail due to either invalid
5227	* address or valid address but requiring a major memory fault. If
5228	* reading kernel memory fails, the string for %s will be an
5229	* empty string, and the ip address for %p{i,I}{4,6} will be 0.
5230	* Not returning error to bpf program is consistent with what
5231	* bpf_trace_printk\ () does for now.
5232	*
5233	* Return
5234	* The strictly positive length of the formatted string, including
5235	* the trailing zero character. If the return value is greater than
5236	* str_size, str contains a truncated string, guaranteed to
5237	* be zero-terminated except when str_size is 0.
5238	*
5239	* Or -EBUSY if the per-CPU memory copy buffer is busy.
5240	*
5241	* long bpf_sys_bpf(u32 cmd, void *attr, u32 attr_size)
5242	* Description
5243	* Execute bpf syscall with given arguments.
5244	* Return
5245	* A syscall result.
5246	*
5247	* long bpf_btf_find_by_name_kind(char *name, int name_sz, u32 kind, int flags)
5248	* Description
5249	* Find BTF type with given name and kind in vmlinux BTF or in module's BTFs.
5250	* Return
5251	* Returns btf_id and btf_obj_fd in lower and upper 32 bits.
5252	*
5253	* long bpf_sys_close(u32 fd)
5254	* Description
5255	* Execute close syscall for given FD.
5256	* Return
5257	* A syscall result.
5258	*
5259	* long bpf_timer_init(struct bpf_timer timer, struct bpf_map map, u64 flags)
5260	* Description
5261	* Initialize the timer.
5262	* First 4 bits of flags specify clockid.
5263	* Only CLOCK_MONOTONIC, CLOCK_REALTIME, CLOCK_BOOTTIME are allowed.
5264	* All other bits of flags are reserved.
5265	* The verifier will reject the program if timer is not from
5266	* the same map.
5267	* Return
5268	* 0 on success.
5269	* -EBUSY if timer is already initialized.
5270	* -EINVAL if invalid flags are passed.
5271	* -EPERM if timer is in a map that doesn't have any user references.
5272	* The user space should either hold a file descriptor to a map with timers
5273	* or pin such map in bpffs. When map is unpinned or file descriptor is
5274	* closed all timers in the map will be cancelled and freed.
5275	*
5276	* long bpf_timer_set_callback(struct bpf_timer timer, void callback_fn)
5277	* Description
5278	* Configure the timer to call callback_fn static function.
5279	* Return
5280	* 0 on success.
5281	* -EINVAL if timer was not initialized with bpf_timer_init() earlier.
5282	* -EPERM if timer is in a map that doesn't have any user references.
5283	* The user space should either hold a file descriptor to a map with timers
5284	* or pin such map in bpffs. When map is unpinned or file descriptor is
5285	* closed all timers in the map will be cancelled and freed.
5286	*
5287	* long bpf_timer_start(struct bpf_timer *timer, u64 nsecs, u64 flags)
5288	* Description
5289	* Set timer expiration N nanoseconds from the current time. The
5290	* configured callback will be invoked in soft irq context on some cpu
5291	* and will not repeat unless another bpf_timer_start() is made.
5292	* In such case the next invocation can migrate to a different cpu.
5293	* Since struct bpf_timer is a field inside map element the map
5294	* owns the timer. The bpf_timer_set_callback() will increment refcnt
5295	* of BPF program to make sure that callback_fn code stays valid.
5296	* When user space reference to a map reaches zero all timers
5297	* in a map are cancelled and corresponding program's refcnts are
5298	* decremented. This is done to make sure that Ctrl-C of a user
5299	* process doesn't leave any timers running. If map is pinned in
5300	* bpffs the callback_fn can re-arm itself indefinitely.
5301	* bpf_map_update/delete_elem() helpers and user space sys_bpf commands
5302	* cancel and free the timer in the given map element.
5303	* The map can contain timers that invoke callback_fn-s from different
5304	* programs. The same callback_fn can serve different timers from
5305	* different maps if key/value layout matches across maps.
5306	* Every bpf_timer_set_callback() can have different callback_fn.
5307	*
5308	* flags can be one of:
5309	*
5310	* BPF_F_TIMER_ABS
5311	* Start the timer in absolute expire value instead of the
5312	* default relative one.
5313	* BPF_F_TIMER_CPU_PIN
5314	* Timer will be pinned to the CPU of the caller.
5315	*
5316	* Return
5317	* 0 on success.
5318	* -EINVAL if timer was not initialized with bpf_timer_init() earlier
5319	* or invalid flags are passed.
5320	*
5321	* long bpf_timer_cancel(struct bpf_timer *timer)
5322	* Description
5323	* Cancel the timer and wait for callback_fn to finish if it was running.
5324	* Return
5325	* 0 if the timer was not active.
5326	* 1 if the timer was active.
5327	* -EINVAL if timer was not initialized with bpf_timer_init() earlier.
5328	* -EDEADLK if callback_fn tried to call bpf_timer_cancel() on its
5329	* own timer which would have led to a deadlock otherwise.
5330	*
5331	* u64 bpf_get_func_ip(void *ctx)
5332	* Description
5333	* Get address of the traced function (for tracing and kprobe programs).
5334	*
5335	* When called for kprobe program attached as uprobe it returns
5336	* probe address for both entry and return uprobe.
5337	*
5338	* Return
5339	* Address of the traced function for kprobe.
5340	* 0 for kprobes placed within the function (not at the entry).
5341	* Address of the probe for uprobe and return uprobe.
5342	*
5343	* u64 bpf_get_attach_cookie(void *ctx)
5344	* Description
5345	* Get bpf_cookie value provided (optionally) during the program
5346	* attachment. It might be different for each individual
5347	* attachment, even if BPF program itself is the same.
5348	* Expects BPF program context ctx as a first argument.
5349	*
5350	* Supported for the following program types:
5351	* - kprobe/uprobe;
5352	* - tracepoint;
5353	* - perf_event.
5354	* Return
5355	* Value specified by user at BPF link creation/attachment time
5356	* or 0, if it was not specified.
5357	*
5358	* long bpf_task_pt_regs(struct task_struct *task)
5359	* Description
5360	* Get the struct pt_regs associated with task.
5361	* Return
5362	* A pointer to struct pt_regs.
5363	*
5364	* long bpf_get_branch_snapshot(void *entries, u32 size, u64 flags)
5365	* Description
5366	* Get branch trace from hardware engines like Intel LBR. The
5367	* hardware engine is stopped shortly after the helper is
5368	* called. Therefore, the user need to filter branch entries
5369	* based on the actual use case. To capture branch trace
5370	* before the trigger point of the BPF program, the helper
5371	* should be called at the beginning of the BPF program.
5372	*
5373	* The data is stored as struct perf_branch_entry into output
5374	* buffer entries. size is the size of entries in bytes.
5375	* flags is reserved for now and must be zero.
5376	*
5377	* Return
5378	* On success, number of bytes written to buf. On error, a
5379	* negative value.
5380	*
5381	* -EINVAL if flags is not zero.
5382	*
5383	* -ENOENT if architecture does not support branch records.
5384	*
5385	* long bpf_trace_vprintk(const char fmt, u32 fmt_size, const void data, u32 data_len)
5386	* Description
5387	* Behaves like bpf_trace_printk\ () helper, but takes an array of u64
5388	* to format and can handle more format args as a result.
5389	*
5390	* Arguments are to be used as in bpf_seq_printf\ () helper.
5391	* Return
5392	* The number of bytes written to the buffer, or a negative error
5393	* in case of failure.
5394	*
5395	* struct unix_sock bpf_skc_to_unix_sock(void sk)
5396	* Description
5397	* Dynamically cast a sk pointer to a unix_sock pointer.
5398	* Return
5399	* sk if casting is valid, or NULL otherwise.
5400	*
5401	* long bpf_kallsyms_lookup_name(const char name, int name_sz, int flags, u64 res)
5402	* Description
5403	* Get the address of a kernel symbol, returned in res. res is
5404	* set to 0 if the symbol is not found.
5405	* Return
5406	* On success, zero. On error, a negative value.
5407	*
5408	* -EINVAL if flags is not zero.
5409	*
5410	* -EINVAL if string name is not the same size as name_sz.
5411	*
5412	* -ENOENT if symbol is not found.
5413	*
5414	* -EPERM if caller does not have permission to obtain kernel address.
5415	*
5416	* long bpf_find_vma(struct task_struct task, u64 addr, void callback_fn, void *callback_ctx, u64 flags)
5417	* Description
5418	* Find vma of task that contains addr, call callback_fn
5419	* function with task, vma, and callback_ctx.
5420	* The callback_fn should be a static function and
5421	* the callback_ctx should be a pointer to the stack.
5422	* The flags is used to control certain aspects of the helper.
5423	* Currently, the flags must be 0.
5424	*
5425	* The expected callback signature is
5426	*
5427	* long (\callback_fn)(struct task_struct \task, struct vm_area_struct \vma, void \callback_ctx);
5428	*
5429	* Return
5430	* 0 on success.
5431	* -ENOENT if task->mm is NULL, or no vma contains addr.
5432	* -EBUSY if failed to try lock mmap_lock.
5433	* -EINVAL for invalid flags.
5434	*
5435	* long bpf_loop(u32 nr_loops, void callback_fn, void callback_ctx, u64 flags)
5436	* Description
5437	* For nr_loops, call callback_fn function
5438	* with callback_ctx as the context parameter.
5439	* The callback_fn should be a static function and
5440	* the callback_ctx should be a pointer to the stack.
5441	* The flags is used to control certain aspects of the helper.
5442	* Currently, the flags must be 0. Currently, nr_loops is
5443	* limited to 1 << 23 (~8 million) loops.
5444	*
5445	* long (\callback_fn)(u64 index, void \ctx);
5446	*
5447	* where index is the current index in the loop. The index
5448	* is zero-indexed.
5449	*
5450	* If callback_fn returns 0, the helper will continue to the next
5451	* loop. If return value is 1, the helper will skip the rest of
5452	* the loops and return. Other return values are not used now,
5453	* and will be rejected by the verifier.
5454	*
5455	* Return
5456	* The number of loops performed, -EINVAL for invalid flags,
5457	* -E2BIG if nr_loops exceeds the maximum number of loops.
5458	*
5459	* long bpf_strncmp(const char s1, u32 s1_sz, const char s2)
5460	* Description
5461	* Do strncmp() between s1 and s2. s1 doesn't need
5462	* to be null-terminated and s1_sz is the maximum storage
5463	* size of s1. s2 must be a read-only string.
5464	* Return
5465	* An integer less than, equal to, or greater than zero
5466	* if the first s1_sz bytes of s1 is found to be
5467	* less than, to match, or be greater than s2.
5468	*
5469	* long bpf_get_func_arg(void ctx, u32 n, u64 value)
5470	* Description
5471	* Get n-th argument register (zero based) of the traced function (for tracing programs)
5472	* returned in value.
5473	*
5474	* Return
5475	* 0 on success.
5476	* -EINVAL if n >= argument register count of traced function.
5477	*
5478	* long bpf_get_func_ret(void ctx, u64 value)
5479	* Description
5480	* Get return value of the traced function (for tracing programs)
5481	* in value.
5482	*
5483	* Return
5484	* 0 on success.
5485	* -EOPNOTSUPP for tracing programs other than BPF_TRACE_FEXIT or BPF_MODIFY_RETURN.
5486	*
5487	* long bpf_get_func_arg_cnt(void *ctx)
5488	* Description
5489	* Get number of registers of the traced function (for tracing programs) where
5490	* function arguments are stored in these registers.
5491	*
5492	* Return
5493	* The number of argument registers of the traced function.
5494	*
5495	* int bpf_get_retval(void)
5496	* Description
5497	* Get the BPF program's return value that will be returned to the upper layers.
5498	*
5499	* This helper is currently supported by cgroup programs and only by the hooks
5500	* where BPF program's return value is returned to the userspace via errno.
5501	* Return
5502	* The BPF program's return value.
5503	*
5504	* int bpf_set_retval(int retval)
5505	* Description
5506	* Set the BPF program's return value that will be returned to the upper layers.
5507	*
5508	* This helper is currently supported by cgroup programs and only by the hooks
5509	* where BPF program's return value is returned to the userspace via errno.
5510	*
5511	* Note that there is the following corner case where the program exports an error
5512	* via bpf_set_retval but signals success via 'return 1':
5513	*
5514	* bpf_set_retval(-EPERM);
5515	* return 1;
5516	*
5517	* In this case, the BPF program's return value will use helper's -EPERM. This
5518	* still holds true for cgroup/bind{4,6} which supports extra 'return 3' success case.
5519	*
5520	* Return
5521	* 0 on success, or a negative error in case of failure.
5522	*
5523	* u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md)
5524	* Description
5525	* Get the total size of a given xdp buff (linear and paged area)
5526	* Return
5527	* The total size of a given xdp buffer.
5528	*
5529	* long bpf_xdp_load_bytes(struct xdp_buff xdp_md, u32 offset, void buf, u32 len)
5530	* Description
5531	* This helper is provided as an easy way to load data from a
5532	* xdp buffer. It can be used to load len bytes from offset from
5533	* the frame associated to xdp_md, into the buffer pointed by
5534	* buf.
5535	* Return
5536	* 0 on success, or a negative error in case of failure.
5537	*
5538	* long bpf_xdp_store_bytes(struct xdp_buff xdp_md, u32 offset, void buf, u32 len)
5539	* Description
5540	* Store len bytes from buffer buf into the frame
5541	* associated to xdp_md, at offset.
5542	* Return
5543	* 0 on success, or a negative error in case of failure.
5544	*
5545	* long bpf_copy_from_user_task(void dst, u32 size, const void user_ptr, struct task_struct *tsk, u64 flags)
5546	* Description
5547	* Read size bytes from user space address user_ptr in tsk's
5548	* address space, and stores the data in dst. flags is not
5549	* used yet and is provided for future extensibility. This helper
5550	* can only be used by sleepable programs.
5551	* Return
5552	* 0 on success, or a negative error in case of failure. On error
5553	* dst buffer is zeroed out.
5554	*
5555	* long bpf_skb_set_tstamp(struct sk_buff *skb, u64 tstamp, u32 tstamp_type)
5556	* Description
5557	* Change the __sk_buff->tstamp_type to tstamp_type
5558	* and set tstamp to the __sk_buff->tstamp together.
5559	*
5560	* If there is no need to change the __sk_buff->tstamp_type,
5561	* the tstamp value can be directly written to __sk_buff->tstamp
5562	* instead.
5563	*
5564	* BPF_SKB_TSTAMP_DELIVERY_MONO is the only tstamp that
5565	* will be kept during bpf_redirect_*(). A non zero
5566	* tstamp must be used with the BPF_SKB_TSTAMP_DELIVERY_MONO
5567	* tstamp_type.
5568	*
5569	* A BPF_SKB_TSTAMP_UNSPEC tstamp_type can only be used
5570	* with a zero tstamp.
5571	*
5572	* Only IPv4 and IPv6 skb->protocol are supported.
5573	*
5574	* This function is most useful when it needs to set a
5575	* mono delivery time to __sk_buff->tstamp and then
5576	* bpf_redirect_*() to the egress of an iface. For example,
5577	* changing the (rcv) timestamp in __sk_buff->tstamp at
5578	* ingress to a mono delivery time and then bpf_redirect_*()
5579	* to sch_fq@phy-dev.
5580	* Return
5581	* 0 on success.
5582	* -EINVAL for invalid input
5583	* -EOPNOTSUPP for unsupported protocol
5584	*
5585	* long bpf_ima_file_hash(struct file file, void dst, u32 size)
5586	* Description
5587	* Returns a calculated IMA hash of the file.
5588	* If the hash is larger than size, then only size
5589	* bytes will be copied to dst
5590	* Return
5591	* The hash_algo is returned on success,
5592	* -EOPNOTSUPP if the hash calculation failed or -EINVAL if
5593	* invalid arguments are passed.
5594	*
5595	* void bpf_kptr_xchg(void dst, void *ptr)
5596	* Description
5597	* Exchange kptr at pointer dst with ptr, and return the old value.
5598	* dst can be map value or local kptr. ptr can be NULL, otherwise
5599	* it must be a referenced pointer which will be released when this helper
5600	* is called.
5601	* Return
5602	* The old value of kptr (which can be NULL). The returned pointer
5603	* if not NULL, is a reference which must be released using its
5604	* corresponding release function, or moved into a BPF map before
5605	* program exit.
5606	*
5607	* void bpf_map_lookup_percpu_elem(struct bpf_map map, const void *key, u32 cpu)
5608	* Description
5609	* Perform a lookup in percpu map for an entry associated to
5610	* key on cpu.
5611	* Return
5612	* Map value associated to key on cpu, or NULL if no entry
5613	* was found or cpu is invalid.
5614	*
5615	* struct mptcp_sock bpf_skc_to_mptcp_sock(void sk)
5616	* Description
5617	* Dynamically cast a sk pointer to a mptcp_sock pointer.
5618	* Return
5619	* sk if casting is valid, or NULL otherwise.
5620	*
5621	* long bpf_dynptr_from_mem(void data, u32 size, u64 flags, struct bpf_dynptr ptr)
5622	* Description
5623	* Get a dynptr to local memory data.
5624	*
5625	* data must be a ptr to a map value.
5626	* The maximum size supported is DYNPTR_MAX_SIZE.
5627	* flags is currently unused.
5628	* Return
5629	* 0 on success, -E2BIG if the size exceeds DYNPTR_MAX_SIZE,
5630	* -EINVAL if flags is not 0.
5631	*
5632	* long bpf_ringbuf_reserve_dynptr(void ringbuf, u32 size, u64 flags, struct bpf_dynptr ptr)
5633	* Description
5634	* Reserve size bytes of payload in a ring buffer ringbuf
5635	* through the dynptr interface. flags must be 0.
5636	*
5637	* Please note that a corresponding bpf_ringbuf_submit_dynptr or
5638	* bpf_ringbuf_discard_dynptr must be called on ptr, even if the
5639	* reservation fails. This is enforced by the verifier.
5640	* Return
5641	* 0 on success, or a negative error in case of failure.
5642	*
5643	* void bpf_ringbuf_submit_dynptr(struct bpf_dynptr *ptr, u64 flags)
5644	* Description
5645	* Submit reserved ring buffer sample, pointed to by data,
5646	* through the dynptr interface. This is a no-op if the dynptr is
5647	* invalid/null.
5648	*
5649	* For more information on flags, please see
5650	* 'bpf_ringbuf_submit'.
5651	* Return
5652	* Nothing. Always succeeds.
5653	*
5654	* void bpf_ringbuf_discard_dynptr(struct bpf_dynptr *ptr, u64 flags)
5655	* Description
5656	* Discard reserved ring buffer sample through the dynptr
5657	* interface. This is a no-op if the dynptr is invalid/null.
5658	*
5659	* For more information on flags, please see
5660	* 'bpf_ringbuf_discard'.
5661	* Return
5662	* Nothing. Always succeeds.
5663	*
5664	* long bpf_dynptr_read(void dst, u32 len, const struct bpf_dynptr src, u32 offset, u64 flags)
5665	* Description
5666	* Read len bytes from src into dst, starting from offset
5667	* into src.
5668	* flags is currently unused.
5669	* Return
5670	* 0 on success, -E2BIG if offset + len exceeds the length
5671	* of src's data, -EINVAL if src is an invalid dynptr or if
5672	* flags is not 0.
5673	*
5674	* long bpf_dynptr_write(const struct bpf_dynptr dst, u32 offset, void src, u32 len, u64 flags)
5675	* Description
5676	* Write len bytes from src into dst, starting from offset
5677	* into dst.
5678	*
5679	* flags must be 0 except for skb-type dynptrs.
5680	*
5681	* For skb-type dynptrs:
5682	* * All data slices of the dynptr are automatically
5683	* invalidated after bpf_dynptr_write\ (). This is
5684	* because writing may pull the skb and change the
5685	* underlying packet buffer.
5686	*
5687	* * For flags, please see the flags accepted by
5688	* bpf_skb_store_bytes\ ().
5689	* Return
5690	* 0 on success, -E2BIG if offset + len exceeds the length
5691	* of dst's data, -EINVAL if dst is an invalid dynptr or if dst
5692	* is a read-only dynptr or if flags is not correct. For skb-type dynptrs,
5693	* other errors correspond to errors returned by bpf_skb_store_bytes\ ().
5694	*
5695	* void bpf_dynptr_data(const struct bpf_dynptr ptr, u32 offset, u32 len)
5696	* Description
5697	* Get a pointer to the underlying dynptr data.
5698	*
5699	* len must be a statically known value. The returned data slice
5700	* is invalidated whenever the dynptr is invalidated.
5701	*
5702	* skb and xdp type dynptrs may not use bpf_dynptr_data. They should
5703	* instead use bpf_dynptr_slice and bpf_dynptr_slice_rdwr.
5704	* Return
5705	* Pointer to the underlying dynptr data, NULL if the dynptr is
5706	* read-only, if the dynptr is invalid, or if the offset and length
5707	* is out of bounds.
5708	*
5709	* s64 bpf_tcp_raw_gen_syncookie_ipv4(struct iphdr iph, struct tcphdr th, u32 th_len)
5710	* Description
5711	* Try to issue a SYN cookie for the packet with corresponding
5712	* IPv4/TCP headers, iph and th, without depending on a
5713	* listening socket.
5714	*
5715	* iph points to the IPv4 header.
5716	*
5717	* th points to the start of the TCP header, while th_len
5718	* contains the length of the TCP header (at least
5719	* sizeof\ (struct tcphdr)).
5720	* Return
5721	* On success, lower 32 bits hold the generated SYN cookie in
5722	* followed by 16 bits which hold the MSS value for that cookie,
5723	* and the top 16 bits are unused.
5724	*
5725	* On failure, the returned value is one of the following:
5726	*
5727	* -EINVAL if th_len is invalid.
5728	*
5729	* s64 bpf_tcp_raw_gen_syncookie_ipv6(struct ipv6hdr iph, struct tcphdr th, u32 th_len)
5730	* Description
5731	* Try to issue a SYN cookie for the packet with corresponding
5732	* IPv6/TCP headers, iph and th, without depending on a
5733	* listening socket.
5734	*
5735	* iph points to the IPv6 header.
5736	*
5737	* th points to the start of the TCP header, while th_len
5738	* contains the length of the TCP header (at least
5739	* sizeof\ (struct tcphdr)).
5740	* Return
5741	* On success, lower 32 bits hold the generated SYN cookie in
5742	* followed by 16 bits which hold the MSS value for that cookie,
5743	* and the top 16 bits are unused.
5744	*
5745	* On failure, the returned value is one of the following:
5746	*
5747	* -EINVAL if th_len is invalid.
5748	*
5749	* -EPROTONOSUPPORT if CONFIG_IPV6 is not builtin.
5750	*
5751	* long bpf_tcp_raw_check_syncookie_ipv4(struct iphdr iph, struct tcphdr th)
5752	* Description
5753	* Check whether iph and th contain a valid SYN cookie ACK
5754	* without depending on a listening socket.
5755	*
5756	* iph points to the IPv4 header.
5757	*
5758	* th points to the TCP header.
5759	* Return
5760	* 0 if iph and th are a valid SYN cookie ACK.
5761	*
5762	* On failure, the returned value is one of the following:
5763	*
5764	* -EACCES if the SYN cookie is not valid.
5765	*
5766	* long bpf_tcp_raw_check_syncookie_ipv6(struct ipv6hdr iph, struct tcphdr th)
5767	* Description
5768	* Check whether iph and th contain a valid SYN cookie ACK
5769	* without depending on a listening socket.
5770	*
5771	* iph points to the IPv6 header.
5772	*
5773	* th points to the TCP header.
5774	* Return
5775	* 0 if iph and th are a valid SYN cookie ACK.
5776	*
5777	* On failure, the returned value is one of the following:
5778	*
5779	* -EACCES if the SYN cookie is not valid.
5780	*
5781	* -EPROTONOSUPPORT if CONFIG_IPV6 is not builtin.
5782	*
5783	* u64 bpf_ktime_get_tai_ns(void)
5784	* Description
5785	* A nonsettable system-wide clock derived from wall-clock time but
5786	* ignoring leap seconds. This clock does not experience
5787	* discontinuities and backwards jumps caused by NTP inserting leap
5788	* seconds as CLOCK_REALTIME does.
5789	*
5790	* See: clock_gettime\ (CLOCK_TAI)
5791	* Return
5792	* Current ktime.
5793	*
5794	* long bpf_user_ringbuf_drain(struct bpf_map map, void callback_fn, void *ctx, u64 flags)
5795	* Description
5796	* Drain samples from the specified user ring buffer, and invoke
5797	* the provided callback for each such sample:
5798	*
5799	* long (\callback_fn)(const struct bpf_dynptr \dynptr, void \*ctx);
5800	*
5801	* If callback_fn returns 0, the helper will continue to try
5802	* and drain the next sample, up to a maximum of
5803	* BPF_MAX_USER_RINGBUF_SAMPLES samples. If the return value is 1,
5804	* the helper will skip the rest of the samples and return. Other
5805	* return values are not used now, and will be rejected by the
5806	* verifier.
5807	* Return
5808	* The number of drained samples if no error was encountered while
5809	* draining samples, or 0 if no samples were present in the ring
5810	* buffer. If a user-space producer was epoll-waiting on this map,
5811	* and at least one sample was drained, they will receive an event
5812	* notification notifying them of available space in the ring
5813	* buffer. If the BPF_RB_NO_WAKEUP flag is passed to this
5814	* function, no wakeup notification will be sent. If the
5815	* BPF_RB_FORCE_WAKEUP flag is passed, a wakeup notification will
5816	* be sent even if no sample was drained.
5817	*
5818	* On failure, the returned value is one of the following:
5819	*
5820	* -EBUSY if the ring buffer is contended, and another calling
5821	* context was concurrently draining the ring buffer.
5822	*
5823	* -EINVAL if user-space is not properly tracking the ring
5824	* buffer due to the producer position not being aligned to 8
5825	* bytes, a sample not being aligned to 8 bytes, or the producer
5826	* position not matching the advertised length of a sample.
5827	*
5828	* -E2BIG if user-space has tried to publish a sample which is
5829	* larger than the size of the ring buffer, or which cannot fit
5830	* within a struct bpf_dynptr.
5831	*
5832	* void bpf_cgrp_storage_get(struct bpf_map map, struct cgroup cgroup, void value, u64 flags)
5833	* Description
5834	* Get a bpf_local_storage from the cgroup.
5835	*
5836	* Logically, it could be thought of as getting the value from
5837	* a map with cgroup as the key. From this
5838	* perspective, the usage is not much different from
5839	* bpf_map_lookup_elem\ (map, &\ cgroup) except this
5840	* helper enforces the key must be a cgroup struct and the map must also
5841	* be a BPF_MAP_TYPE_CGRP_STORAGE.
5842	*
5843	* In reality, the local-storage value is embedded directly inside of the
5844	* cgroup object itself, rather than being located in the
5845	* BPF_MAP_TYPE_CGRP_STORAGE map. When the local-storage value is
5846	* queried for some map on a cgroup object, the kernel will perform an
5847	* O(n) iteration over all of the live local-storage values for that
5848	* cgroup object until the local-storage value for the map is found.
5849	*
5850	* An optional flags (BPF_LOCAL_STORAGE_GET_F_CREATE) can be
5851	* used such that a new bpf_local_storage will be
5852	* created if one does not exist. value can be used
5853	* together with BPF_LOCAL_STORAGE_GET_F_CREATE to specify
5854	* the initial value of a bpf_local_storage. If value is
5855	* NULL, the new bpf_local_storage will be zero initialized.
5856	* Return
5857	* A bpf_local_storage pointer is returned on success.
5858	*
5859	* NULL if not found or there was an error in adding
5860	* a new bpf_local_storage.
5861	*
5862	* long bpf_cgrp_storage_delete(struct bpf_map map, struct cgroup cgroup)
5863	* Description
5864	* Delete a bpf_local_storage from a cgroup.
5865	* Return
5866	* 0 on success.
5867	*
5868	* -ENOENT if the bpf_local_storage cannot be found.
5869	*/
5870	#define ___BPF_FUNC_MAPPER(FN, ctx...) \
5871	FN(unspec, 0, ##ctx) \
5872	FN(map_lookup_elem, 1, ##ctx) \
5873	FN(map_update_elem, 2, ##ctx) \
5874	FN(map_delete_elem, 3, ##ctx) \
5875	FN(probe_read, 4, ##ctx) \
5876	FN(ktime_get_ns, 5, ##ctx) \
5877	FN(trace_printk, 6, ##ctx) \
5878	FN(get_prandom_u32, 7, ##ctx) \
5879	FN(get_smp_processor_id, 8, ##ctx) \
5880	FN(skb_store_bytes, 9, ##ctx) \
5881	FN(l3_csum_replace, 10, ##ctx) \
5882	FN(l4_csum_replace, 11, ##ctx) \
5883	FN(tail_call, 12, ##ctx) \
5884	FN(clone_redirect, 13, ##ctx) \
5885	FN(get_current_pid_tgid, 14, ##ctx) \
5886	FN(get_current_uid_gid, 15, ##ctx) \
5887	FN(get_current_comm, 16, ##ctx) \
5888	FN(get_cgroup_classid, 17, ##ctx) \
5889	FN(skb_vlan_push, 18, ##ctx) \
5890	FN(skb_vlan_pop, 19, ##ctx) \
5891	FN(skb_get_tunnel_key, 20, ##ctx) \
5892	FN(skb_set_tunnel_key, 21, ##ctx) \
5893	FN(perf_event_read, 22, ##ctx) \
5894	FN(redirect, 23, ##ctx) \
5895	FN(get_route_realm, 24, ##ctx) \
5896	FN(perf_event_output, 25, ##ctx) \
5897	FN(skb_load_bytes, 26, ##ctx) \
5898	FN(get_stackid, 27, ##ctx) \
5899	FN(csum_diff, 28, ##ctx) \
5900	FN(skb_get_tunnel_opt, 29, ##ctx) \
5901	FN(skb_set_tunnel_opt, 30, ##ctx) \
5902	FN(skb_change_proto, 31, ##ctx) \
5903	FN(skb_change_type, 32, ##ctx) \
5904	FN(skb_under_cgroup, 33, ##ctx) \
5905	FN(get_hash_recalc, 34, ##ctx) \
5906	FN(get_current_task, 35, ##ctx) \
5907	FN(probe_write_user, 36, ##ctx) \
5908	FN(current_task_under_cgroup, 37, ##ctx) \
5909	FN(skb_change_tail, 38, ##ctx) \
5910	FN(skb_pull_data, 39, ##ctx) \
5911	FN(csum_update, 40, ##ctx) \
5912	FN(set_hash_invalid, 41, ##ctx) \
5913	FN(get_numa_node_id, 42, ##ctx) \
5914	FN(skb_change_head, 43, ##ctx) \
5915	FN(xdp_adjust_head, 44, ##ctx) \
5916	FN(probe_read_str, 45, ##ctx) \
5917	FN(get_socket_cookie, 46, ##ctx) \
5918	FN(get_socket_uid, 47, ##ctx) \
5919	FN(set_hash, 48, ##ctx) \
5920	FN(setsockopt, 49, ##ctx) \
5921	FN(skb_adjust_room, 50, ##ctx) \
5922	FN(redirect_map, 51, ##ctx) \
5923	FN(sk_redirect_map, 52, ##ctx) \
5924	FN(sock_map_update, 53, ##ctx) \
5925	FN(xdp_adjust_meta, 54, ##ctx) \
5926	FN(perf_event_read_value, 55, ##ctx) \
5927	FN(perf_prog_read_value, 56, ##ctx) \
5928	FN(getsockopt, 57, ##ctx) \
5929	FN(override_return, 58, ##ctx) \
5930	FN(sock_ops_cb_flags_set, 59, ##ctx) \
5931	FN(msg_redirect_map, 60, ##ctx) \
5932	FN(msg_apply_bytes, 61, ##ctx) \
5933	FN(msg_cork_bytes, 62, ##ctx) \
5934	FN(msg_pull_data, 63, ##ctx) \
5935	FN(bind, 64, ##ctx) \
5936	FN(xdp_adjust_tail, 65, ##ctx) \
5937	FN(skb_get_xfrm_state, 66, ##ctx) \
5938	FN(get_stack, 67, ##ctx) \
5939	FN(skb_load_bytes_relative, 68, ##ctx) \
5940	FN(fib_lookup, 69, ##ctx) \
5941	FN(sock_hash_update, 70, ##ctx) \
5942	FN(msg_redirect_hash, 71, ##ctx) \
5943	FN(sk_redirect_hash, 72, ##ctx) \
5944	FN(lwt_push_encap, 73, ##ctx) \
5945	FN(lwt_seg6_store_bytes, 74, ##ctx) \
5946	FN(lwt_seg6_adjust_srh, 75, ##ctx) \
5947	FN(lwt_seg6_action, 76, ##ctx) \
5948	FN(rc_repeat, 77, ##ctx) \
5949	FN(rc_keydown, 78, ##ctx) \
5950	FN(skb_cgroup_id, 79, ##ctx) \
5951	FN(get_current_cgroup_id, 80, ##ctx) \
5952	FN(get_local_storage, 81, ##ctx) \
5953	FN(sk_select_reuseport, 82, ##ctx) \
5954	FN(skb_ancestor_cgroup_id, 83, ##ctx) \
5955	FN(sk_lookup_tcp, 84, ##ctx) \
5956	FN(sk_lookup_udp, 85, ##ctx) \
5957	FN(sk_release, 86, ##ctx) \
5958	FN(map_push_elem, 87, ##ctx) \
5959	FN(map_pop_elem, 88, ##ctx) \
5960	FN(map_peek_elem, 89, ##ctx) \
5961	FN(msg_push_data, 90, ##ctx) \
5962	FN(msg_pop_data, 91, ##ctx) \
5963	FN(rc_pointer_rel, 92, ##ctx) \
5964	FN(spin_lock, 93, ##ctx) \
5965	FN(spin_unlock, 94, ##ctx) \
5966	FN(sk_fullsock, 95, ##ctx) \
5967	FN(tcp_sock, 96, ##ctx) \
5968	FN(skb_ecn_set_ce, 97, ##ctx) \
5969	FN(get_listener_sock, 98, ##ctx) \
5970	FN(skc_lookup_tcp, 99, ##ctx) \
5971	FN(tcp_check_syncookie, 100, ##ctx) \
5972	FN(sysctl_get_name, 101, ##ctx) \
5973	FN(sysctl_get_current_value, 102, ##ctx) \
5974	FN(sysctl_get_new_value, 103, ##ctx) \
5975	FN(sysctl_set_new_value, 104, ##ctx) \
5976	FN(strtol, 105, ##ctx) \
5977	FN(strtoul, 106, ##ctx) \
5978	FN(sk_storage_get, 107, ##ctx) \
5979	FN(sk_storage_delete, 108, ##ctx) \
5980	FN(send_signal, 109, ##ctx) \
5981	FN(tcp_gen_syncookie, 110, ##ctx) \
5982	FN(skb_output, 111, ##ctx) \
5983	FN(probe_read_user, 112, ##ctx) \
5984	FN(probe_read_kernel, 113, ##ctx) \
5985	FN(probe_read_user_str, 114, ##ctx) \
5986	FN(probe_read_kernel_str, 115, ##ctx) \
5987	FN(tcp_send_ack, 116, ##ctx) \
5988	FN(send_signal_thread, 117, ##ctx) \
5989	FN(jiffies64, 118, ##ctx) \
5990	FN(read_branch_records, 119, ##ctx) \
5991	FN(get_ns_current_pid_tgid, 120, ##ctx) \
5992	FN(xdp_output, 121, ##ctx) \
5993	FN(get_netns_cookie, 122, ##ctx) \
5994	FN(get_current_ancestor_cgroup_id, 123, ##ctx) \
5995	FN(sk_assign, 124, ##ctx) \
5996	FN(ktime_get_boot_ns, 125, ##ctx) \
5997	FN(seq_printf, 126, ##ctx) \
5998	FN(seq_write, 127, ##ctx) \
5999	FN(sk_cgroup_id, 128, ##ctx) \
6000	FN(sk_ancestor_cgroup_id, 129, ##ctx) \
6001	FN(ringbuf_output, 130, ##ctx) \
6002	FN(ringbuf_reserve, 131, ##ctx) \
6003	FN(ringbuf_submit, 132, ##ctx) \
6004	FN(ringbuf_discard, 133, ##ctx) \
6005	FN(ringbuf_query, 134, ##ctx) \
6006	FN(csum_level, 135, ##ctx) \
6007	FN(skc_to_tcp6_sock, 136, ##ctx) \
6008	FN(skc_to_tcp_sock, 137, ##ctx) \
6009	FN(skc_to_tcp_timewait_sock, 138, ##ctx) \
6010	FN(skc_to_tcp_request_sock, 139, ##ctx) \
6011	FN(skc_to_udp6_sock, 140, ##ctx) \
6012	FN(get_task_stack, 141, ##ctx) \
6013	FN(load_hdr_opt, 142, ##ctx) \
6014	FN(store_hdr_opt, 143, ##ctx) \
6015	FN(reserve_hdr_opt, 144, ##ctx) \
6016	FN(inode_storage_get, 145, ##ctx) \
6017	FN(inode_storage_delete, 146, ##ctx) \
6018	FN(d_path, 147, ##ctx) \
6019	FN(copy_from_user, 148, ##ctx) \
6020	FN(snprintf_btf, 149, ##ctx) \
6021	FN(seq_printf_btf, 150, ##ctx) \
6022	FN(skb_cgroup_classid, 151, ##ctx) \
6023	FN(redirect_neigh, 152, ##ctx) \
6024	FN(per_cpu_ptr, 153, ##ctx) \
6025	FN(this_cpu_ptr, 154, ##ctx) \
6026	FN(redirect_peer, 155, ##ctx) \
6027	FN(task_storage_get, 156, ##ctx) \
6028	FN(task_storage_delete, 157, ##ctx) \
6029	FN(get_current_task_btf, 158, ##ctx) \
6030	FN(bprm_opts_set, 159, ##ctx) \
6031	FN(ktime_get_coarse_ns, 160, ##ctx) \
6032	FN(ima_inode_hash, 161, ##ctx) \
6033	FN(sock_from_file, 162, ##ctx) \
6034	FN(check_mtu, 163, ##ctx) \
6035	FN(for_each_map_elem, 164, ##ctx) \
6036	FN(snprintf, 165, ##ctx) \
6037	FN(sys_bpf, 166, ##ctx) \
6038	FN(btf_find_by_name_kind, 167, ##ctx) \
6039	FN(sys_close, 168, ##ctx) \
6040	FN(timer_init, 169, ##ctx) \
6041	FN(timer_set_callback, 170, ##ctx) \
6042	FN(timer_start, 171, ##ctx) \
6043	FN(timer_cancel, 172, ##ctx) \
6044	FN(get_func_ip, 173, ##ctx) \
6045	FN(get_attach_cookie, 174, ##ctx) \
6046	FN(task_pt_regs, 175, ##ctx) \
6047	FN(get_branch_snapshot, 176, ##ctx) \
6048	FN(trace_vprintk, 177, ##ctx) \
6049	FN(skc_to_unix_sock, 178, ##ctx) \
6050	FN(kallsyms_lookup_name, 179, ##ctx) \
6051	FN(find_vma, 180, ##ctx) \
6052	FN(loop, 181, ##ctx) \
6053	FN(strncmp, 182, ##ctx) \
6054	FN(get_func_arg, 183, ##ctx) \
6055	FN(get_func_ret, 184, ##ctx) \
6056	FN(get_func_arg_cnt, 185, ##ctx) \
6057	FN(get_retval, 186, ##ctx) \
6058	FN(set_retval, 187, ##ctx) \
6059	FN(xdp_get_buff_len, 188, ##ctx) \
6060	FN(xdp_load_bytes, 189, ##ctx) \
6061	FN(xdp_store_bytes, 190, ##ctx) \
6062	FN(copy_from_user_task, 191, ##ctx) \
6063	FN(skb_set_tstamp, 192, ##ctx) \
6064	FN(ima_file_hash, 193, ##ctx) \
6065	FN(kptr_xchg, 194, ##ctx) \
6066	FN(map_lookup_percpu_elem, 195, ##ctx) \
6067	FN(skc_to_mptcp_sock, 196, ##ctx) \
6068	FN(dynptr_from_mem, 197, ##ctx) \
6069	FN(ringbuf_reserve_dynptr, 198, ##ctx) \
6070	FN(ringbuf_submit_dynptr, 199, ##ctx) \
6071	FN(ringbuf_discard_dynptr, 200, ##ctx) \
6072	FN(dynptr_read, 201, ##ctx) \
6073	FN(dynptr_write, 202, ##ctx) \
6074	FN(dynptr_data, 203, ##ctx) \
6075	FN(tcp_raw_gen_syncookie_ipv4, 204, ##ctx) \
6076	FN(tcp_raw_gen_syncookie_ipv6, 205, ##ctx) \
6077	FN(tcp_raw_check_syncookie_ipv4, 206, ##ctx) \
6078	FN(tcp_raw_check_syncookie_ipv6, 207, ##ctx) \
6079	FN(ktime_get_tai_ns, 208, ##ctx) \
6080	FN(user_ringbuf_drain, 209, ##ctx) \
6081	FN(cgrp_storage_get, 210, ##ctx) \
6082	FN(cgrp_storage_delete, 211, ##ctx) \
6083	/* This helper list is effectively frozen. If you are trying to \
6084	* add a new helper, you should add a kfunc instead which has \
6085	* less stability guarantees. See Documentation/bpf/kfuncs.rst \
6086	*/
6087
6088	/ backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't*
6089	* know or care about integer value that is now passed as second argument
6090	*/
6091	#define __BPF_FUNC_MAPPER_APPLY(name, value, FN) FN(name),
6092	#define __BPF_FUNC_MAPPER(FN) ___BPF_FUNC_MAPPER(__BPF_FUNC_MAPPER_APPLY, FN)
6093
6094	/ integer value in 'imm' field of BPF_CALL instruction selects which helper*
6095	* function eBPF program intends to call
6096	*/
6097	#define __BPF_ENUM_FN(x, y) BPF_FUNC_ ## x = y,
6098	enum bpf_func_id {
6099	___BPF_FUNC_MAPPER(__BPF_ENUM_FN)
6100	__BPF_FUNC_MAX_ID,
6101	};
6102	#undef __BPF_ENUM_FN
6103
6104	/ All flags used by eBPF helper functions, placed here. /
6105
6106	/ BPF_FUNC_skb_store_bytes flags. /
6107	enum {
6108	BPF_F_RECOMPUTE_CSUM = (`1ULL` << `0`),
6109	BPF_F_INVALIDATE_HASH = (`1ULL` << `1`),
6110	};
6111
6112	/ BPF_FUNC_l3_csum_replace and BPF_FUNC_l4_csum_replace flags.*
6113	* First 4 bits are for passing the header field size.
6114	*/
6115	enum {
6116	BPF_F_HDR_FIELD_MASK = `0xfULL`,
6117	};
6118
6119	/ BPF_FUNC_l4_csum_replace flags. /
6120	enum {
6121	BPF_F_PSEUDO_HDR = (`1ULL` << `4`),
6122	BPF_F_MARK_MANGLED_0 = (`1ULL` << `5`),
6123	BPF_F_MARK_ENFORCE = (`1ULL` << `6`),
6124	BPF_F_IPV6 = (`1ULL` << `7`),
6125	};
6126
6127	/ BPF_FUNC_skb_set_tunnel_key and BPF_FUNC_skb_get_tunnel_key flags. /
6128	enum {
6129	BPF_F_TUNINFO_IPV6 = (`1ULL` << `0`),
6130	};
6131
6132	/ flags for both BPF_FUNC_get_stackid and BPF_FUNC_get_stack. /
6133	enum {
6134	BPF_F_SKIP_FIELD_MASK = `0xffULL`,
6135	BPF_F_USER_STACK = (`1ULL` << `8`),
6136	/ flags used by BPF_FUNC_get_stackid only. /
6137	BPF_F_FAST_STACK_CMP = (`1ULL` << `9`),
6138	BPF_F_REUSE_STACKID = (`1ULL` << `10`),
6139	/ flags used by BPF_FUNC_get_stack only. /
6140	BPF_F_USER_BUILD_ID = (`1ULL` << `11`),
6141	};
6142
6143	/ BPF_FUNC_skb_set_tunnel_key flags. /
6144	enum {
6145	BPF_F_ZERO_CSUM_TX = (`1ULL` << `1`),
6146	BPF_F_DONT_FRAGMENT = (`1ULL` << `2`),
6147	BPF_F_SEQ_NUMBER = (`1ULL` << `3`),
6148	BPF_F_NO_TUNNEL_KEY = (`1ULL` << `4`),
6149	};
6150
6151	/ BPF_FUNC_skb_get_tunnel_key flags. /
6152	enum {
6153	BPF_F_TUNINFO_FLAGS = (`1ULL` << `4`),
6154	};
6155
6156	/ BPF_FUNC_perf_event_output, BPF_FUNC_perf_event_read and*
6157	* BPF_FUNC_perf_event_read_value flags.
6158	*/
6159	enum {
6160	BPF_F_INDEX_MASK = `0xffffffffULL`,
6161	BPF_F_CURRENT_CPU = BPF_F_INDEX_MASK,
6162	/ BPF_FUNC_perf_event_output for sk_buff input context. /
6163	BPF_F_CTXLEN_MASK = (`0xfffffULL` << `32`),
6164	};
6165
6166	/ Current network namespace /
6167	enum {
6168	BPF_F_CURRENT_NETNS = (-`1L`),
6169	};
6170
6171	/ BPF_FUNC_csum_level level values. /
6172	enum {
6173	BPF_CSUM_LEVEL_QUERY,
6174	BPF_CSUM_LEVEL_INC,
6175	BPF_CSUM_LEVEL_DEC,
6176	BPF_CSUM_LEVEL_RESET,
6177	};
6178
6179	/ BPF_FUNC_skb_adjust_room flags. /
6180	enum {
6181	BPF_F_ADJ_ROOM_FIXED_GSO = (`1ULL` << `0`),
6182	BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 = (`1ULL` << `1`),
6183	BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 = (`1ULL` << `2`),
6184	BPF_F_ADJ_ROOM_ENCAP_L4_GRE = (`1ULL` << `3`),
6185	BPF_F_ADJ_ROOM_ENCAP_L4_UDP = (`1ULL` << `4`),
6186	BPF_F_ADJ_ROOM_NO_CSUM_RESET = (`1ULL` << `5`),
6187	BPF_F_ADJ_ROOM_ENCAP_L2_ETH = (`1ULL` << `6`),
6188	BPF_F_ADJ_ROOM_DECAP_L3_IPV4 = (`1ULL` << `7`),
6189	BPF_F_ADJ_ROOM_DECAP_L3_IPV6 = (`1ULL` << `8`),
6190	};
6191
6192	enum {
6193	BPF_ADJ_ROOM_ENCAP_L2_MASK = `0xff`,
6194	BPF_ADJ_ROOM_ENCAP_L2_SHIFT = `56`,
6195	};
6196
6197	#define BPF_F_ADJ_ROOM_ENCAP_L2(len) (((__u64)len & \
6198	BPF_ADJ_ROOM_ENCAP_L2_MASK) \
6199	<< BPF_ADJ_ROOM_ENCAP_L2_SHIFT)
6200
6201	/ BPF_FUNC_sysctl_get_name flags. /
6202	enum {
6203	BPF_F_SYSCTL_BASE_NAME = (`1ULL` << `0`),
6204	};
6205
6206	/ BPF_FUNC_<kernel_obj>_storage_get flags /
6207	enum {
6208	BPF_LOCAL_STORAGE_GET_F_CREATE = (`1ULL` << `0`),
6209	/ BPF_SK_STORAGE_GET_F_CREATE is only kept for backward compatibility*
6210	* and BPF_LOCAL_STORAGE_GET_F_CREATE must be used instead.
6211	*/
6212	BPF_SK_STORAGE_GET_F_CREATE = BPF_LOCAL_STORAGE_GET_F_CREATE,
6213	};
6214
6215	/ BPF_FUNC_read_branch_records flags. /
6216	enum {
6217	BPF_F_GET_BRANCH_RECORDS_SIZE = (`1ULL` << `0`),
6218	};
6219
6220	/ BPF_FUNC_bpf_ringbuf_commit, BPF_FUNC_bpf_ringbuf_discard, and*
6221	* BPF_FUNC_bpf_ringbuf_output flags.
6222	*/
6223	enum {
6224	BPF_RB_NO_WAKEUP = (`1ULL` << `0`),
6225	BPF_RB_FORCE_WAKEUP = (`1ULL` << `1`),
6226	};
6227
6228	/ BPF_FUNC_bpf_ringbuf_query flags /
6229	enum {
6230	BPF_RB_AVAIL_DATA = `0`,
6231	BPF_RB_RING_SIZE = `1`,
6232	BPF_RB_CONS_POS = `2`,
6233	BPF_RB_PROD_POS = `3`,
6234	};
6235
6236	/ BPF ring buffer constants /
6237	enum {
6238	BPF_RINGBUF_BUSY_BIT = (`1U` << `31`),
6239	BPF_RINGBUF_DISCARD_BIT = (`1U` << `30`),
6240	BPF_RINGBUF_HDR_SZ = `8`,
6241	};
6242
6243	/ BPF_FUNC_sk_assign flags in bpf_sk_lookup context. /
6244	enum {
6245	BPF_SK_LOOKUP_F_REPLACE = (`1ULL` << `0`),
6246	BPF_SK_LOOKUP_F_NO_REUSEPORT = (`1ULL` << `1`),
6247	};
6248
6249	/ Mode for BPF_FUNC_skb_adjust_room helper. /
6250	enum bpf_adj_room_mode {
6251	BPF_ADJ_ROOM_NET,
6252	BPF_ADJ_ROOM_MAC,
6253	};
6254
6255	/ Mode for BPF_FUNC_skb_load_bytes_relative helper. /
6256	enum bpf_hdr_start_off {
6257	BPF_HDR_START_MAC,
6258	BPF_HDR_START_NET,
6259	};
6260
6261	/ Encapsulation type for BPF_FUNC_lwt_push_encap helper. /
6262	enum bpf_lwt_encap_mode {
6263	BPF_LWT_ENCAP_SEG6,
6264	BPF_LWT_ENCAP_SEG6_INLINE,
6265	BPF_LWT_ENCAP_IP,
6266	};
6267
6268	/ Flags for bpf_bprm_opts_set helper /
6269	enum {
6270	BPF_F_BPRM_SECUREEXEC = (`1ULL` << `0`),
6271	};
6272
6273	/ Flags for bpf_redirect and bpf_redirect_map helpers /
6274	enum {
6275	BPF_F_INGRESS = (`1ULL` << `0`), / used for skb path /
6276	BPF_F_BROADCAST = (`1ULL` << `3`), / used for XDP path /
6277	BPF_F_EXCLUDE_INGRESS = (`1ULL` << `4`), / used for XDP path /
6278	#define BPF_F_REDIRECT_FLAGS (BPF_F_INGRESS \| BPF_F_BROADCAST \| BPF_F_EXCLUDE_INGRESS)
6279	};
6280
6281	#define __bpf_md_ptr(type, name) \
6282	union { \
6283	type name; \
6284	__u64 :64; \
6285	} __attribute__((aligned(8)))
6286
6287	/ The enum used in skb->tstamp_type. It specifies the clock type*
6288	* of the time stored in the skb->tstamp.
6289	*/
6290	enum {
6291	BPF_SKB_TSTAMP_UNSPEC = `0`, / DEPRECATED /
6292	BPF_SKB_TSTAMP_DELIVERY_MONO = `1`, / DEPRECATED /
6293	BPF_SKB_CLOCK_REALTIME = `0`,
6294	BPF_SKB_CLOCK_MONOTONIC = `1`,
6295	BPF_SKB_CLOCK_TAI = `2`,
6296	/ For any future BPF_SKB_CLOCK_* that the bpf prog cannot handle,*
6297	* the bpf prog can try to deduce it by ingress/egress/skb->sk->sk_clockid.
6298	*/
6299	};
6300
6301	/ user accessible mirror of in-kernel sk_buff.*
6302	* new fields can only be added to the end of this structure
6303	*/
6304	struct __sk_buff {
6305	__u32 len;
6306	__u32 pkt_type;
6307	__u32 mark;
6308	__u32 queue_mapping;
6309	__u32 protocol;
6310	__u32 vlan_present;
6311	__u32 vlan_tci;
6312	__u32 vlan_proto;
6313	__u32 priority;
6314	__u32 ingress_ifindex;
6315	__u32 ifindex;
6316	__u32 tc_index;
6317	__u32 cb[`5`];
6318	__u32 hash;
6319	__u32 tc_classid;
6320	__u32 data;
6321	__u32 data_end;
6322	__u32 napi_id;
6323
6324	/ Accessed by BPF_PROG_TYPE_sk_skb types from here to ... /
6325	__u32 family;
6326	__u32 remote_ip4; / Stored in network byte order /
6327	__u32 local_ip4; / Stored in network byte order /
6328	__u32 remote_ip6[`4`]; / Stored in network byte order /
6329	__u32 local_ip6[`4`]; / Stored in network byte order /
6330	__u32 remote_port; / Stored in network byte order /
6331	__u32 local_port; / stored in host byte order /
6332	/ ... here. /
6333
6334	__u32 data_meta;
6335	__bpf_md_ptr(struct bpf_flow_keys *, flow_keys);
6336	__u64 tstamp;
6337	__u32 wire_len;
6338	__u32 gso_segs;
6339	__bpf_md_ptr(struct bpf_sock *, sk);
6340	__u32 gso_size;
6341	__u8 tstamp_type;
6342	__u32 :`24`; / Padding, future use. /
6343	__u64 hwtstamp;
6344	};
6345
6346	struct bpf_tunnel_key {
6347	__u32 tunnel_id;
6348	union {
6349	__u32 remote_ipv4;
6350	__u32 remote_ipv6[`4`];
6351	};
6352	__u8 tunnel_tos;
6353	__u8 tunnel_ttl;
6354	union {
6355	__u16 tunnel_ext; / compat /
6356	__be16 tunnel_flags;
6357	};
6358	__u32 tunnel_label;
6359	union {
6360	__u32 local_ipv4;
6361	__u32 local_ipv6[`4`];
6362	};
6363	};
6364
6365	/ user accessible mirror of in-kernel xfrm_state.*
6366	* new fields can only be added to the end of this structure
6367	*/
6368	struct bpf_xfrm_state {
6369	__u32 reqid;
6370	__u32 spi; / Stored in network byte order /
6371	__u16 family;
6372	__u16 ext; / Padding, future use. /
6373	union {
6374	__u32 remote_ipv4; / Stored in network byte order /
6375	__u32 remote_ipv6[`4`]; / Stored in network byte order /
6376	};
6377	};
6378
6379	/ Generic BPF return codes which all BPF program types may support.*
6380	* The values are binary compatible with their TC_ACT_* counter-part to
6381	* provide backwards compatibility with existing SCHED_CLS and SCHED_ACT
6382	* programs.
6383	*
6384	* XDP is handled seprately, see XDP_*.
6385	*/
6386	enum bpf_ret_code {
6387	BPF_OK = `0`,
6388	/ 1 reserved /
6389	BPF_DROP = `2`,
6390	/ 3-6 reserved /
6391	BPF_REDIRECT = `7`,
6392	/ >127 are reserved for prog type specific return codes.*
6393	*
6394	* BPF_LWT_REROUTE: used by BPF_PROG_TYPE_LWT_IN and
6395	* BPF_PROG_TYPE_LWT_XMIT to indicate that skb had been
6396	* changed and should be routed based on its new L3 header.
6397	* (This is an L3 redirect, as opposed to L2 redirect
6398	* represented by BPF_REDIRECT above).
6399	*/
6400	BPF_LWT_REROUTE = `128`,
6401	/ BPF_FLOW_DISSECTOR_CONTINUE: used by BPF_PROG_TYPE_FLOW_DISSECTOR*
6402	* to indicate that no custom dissection was performed, and
6403	* fallback to standard dissector is requested.
6404	*/
6405	BPF_FLOW_DISSECTOR_CONTINUE = `129`,
6406	};
6407
6408	struct bpf_sock {
6409	__u32 bound_dev_if;
6410	__u32 family;
6411	__u32 type;
6412	__u32 protocol;
6413	__u32 mark;
6414	__u32 priority;
6415	/ IP address also allows 1 and 2 bytes access /
6416	__u32 src_ip4;
6417	__u32 src_ip6[`4`];
6418	__u32 src_port; / host byte order /
6419	__be16 dst_port; / network byte order /
6420	__u16 :`16`; / zero padding /
6421	__u32 dst_ip4;
6422	__u32 dst_ip6[`4`];
6423	__u32 state;
6424	__s32 rx_queue_mapping;
6425	};
6426
6427	struct bpf_tcp_sock {
6428	__u32 snd_cwnd; / Sending congestion window /
6429	__u32 srtt_us; / smoothed round trip time << 3 in usecs /
6430	__u32 rtt_min;
6431	__u32 snd_ssthresh; / Slow start size threshold /
6432	__u32 rcv_nxt; / What we want to receive next /
6433	__u32 snd_nxt; / Next sequence we send /
6434	__u32 snd_una; / First byte we want an ack for /
6435	__u32 mss_cache; / Cached effective mss, not including SACKS /
6436	__u32 ecn_flags; / ECN status bits. /
6437	__u32 rate_delivered; / saved rate sample: packets delivered /
6438	__u32 rate_interval_us; / saved rate sample: time elapsed /
6439	__u32 packets_out; / Packets which are "in flight" /
6440	__u32 retrans_out; / Retransmitted packets out /
6441	__u32 total_retrans; / Total retransmits for entire connection /
6442	__u32 segs_in; / RFC4898 tcpEStatsPerfSegsIn*
6443	* total number of segments in.
6444	*/
6445	__u32 data_segs_in; / RFC4898 tcpEStatsPerfDataSegsIn*
6446	* total number of data segments in.
6447	*/
6448	__u32 segs_out; / RFC4898 tcpEStatsPerfSegsOut*
6449	* The total number of segments sent.
6450	*/
6451	__u32 data_segs_out; / RFC4898 tcpEStatsPerfDataSegsOut*
6452	* total number of data segments sent.
6453	*/
6454	__u32 lost_out; / Lost packets /
6455	__u32 sacked_out; / SACK'd packets /
6456	__u64 bytes_received; / RFC4898 tcpEStatsAppHCThruOctetsReceived*
6457	* sum(delta(rcv_nxt)), or how many bytes
6458	* were acked.
6459	*/
6460	__u64 bytes_acked; / RFC4898 tcpEStatsAppHCThruOctetsAcked*
6461	* sum(delta(snd_una)), or how many bytes
6462	* were acked.
6463	*/
6464	__u32 dsack_dups; / RFC4898 tcpEStatsStackDSACKDups*
6465	* total number of DSACK blocks received
6466	*/
6467	__u32 delivered; / Total data packets delivered incl. rexmits /
6468	__u32 delivered_ce; / Like the above but only ECE marked packets /
6469	__u32 icsk_retransmits; / Number of unrecovered [RTO] timeouts /
6470	};
6471
6472	struct bpf_sock_tuple {
6473	union {
6474	struct {
6475	__be32 saddr;
6476	__be32 daddr;
6477	__be16 sport;
6478	__be16 dport;
6479	} ipv4;
6480	struct {
6481	__be32 saddr[`4`];
6482	__be32 daddr[`4`];
6483	__be16 sport;
6484	__be16 dport;
6485	} ipv6;
6486	};
6487	};
6488
6489	/ (Simplified) user return codes for tcx prog type.*
6490	* A valid tcx program must return one of these defined values. All other
6491	* return codes are reserved for future use. Must remain compatible with
6492	* their TC_ACT_* counter-parts. For compatibility in behavior, unknown
6493	* return codes are mapped to TCX_NEXT.
6494	*/
6495	enum tcx_action_base {
6496	TCX_NEXT = -`1`,
6497	TCX_PASS = `0`,
6498	TCX_DROP = `2`,
6499	TCX_REDIRECT = `7`,
6500	};
6501
6502	struct bpf_xdp_sock {
6503	__u32 queue_id;
6504	};
6505
6506	#define XDP_PACKET_HEADROOM 256
6507
6508	/ User return codes for XDP prog type.*
6509	* A valid XDP program must return one of these defined values. All other
6510	* return codes are reserved for future use. Unknown return codes will
6511	* result in packet drops and a warning via bpf_warn_invalid_xdp_action().
6512	*/
6513	enum xdp_action {
6514	XDP_ABORTED = `0`,
6515	XDP_DROP,
6516	XDP_PASS,
6517	XDP_TX,
6518	XDP_REDIRECT,
6519	};
6520
6521	/ user accessible metadata for XDP packet hook*
6522	* new fields must be added to the end of this structure
6523	*/
6524	struct xdp_md {
6525	__u32 data;
6526	__u32 data_end;
6527	__u32 data_meta;
6528	/ Below access go through struct xdp_rxq_info /
6529	__u32 ingress_ifindex; / rxq->dev->ifindex /
6530	__u32 rx_queue_index; / rxq->queue_index /
6531
6532	__u32 egress_ifindex; / txq->dev->ifindex /
6533	};
6534
6535	/ DEVMAP map-value layout*
6536	*
6537	* The struct data-layout of map-value is a configuration interface.
6538	* New members can only be added to the end of this structure.
6539	*/
6540	struct bpf_devmap_val {
6541	__u32 ifindex; / device index /
6542	union {
6543	int fd; / prog fd on map write /
6544	__u32 id; / prog id on map read /
6545	} bpf_prog;
6546	};
6547
6548	/ CPUMAP map-value layout*
6549	*
6550	* The struct data-layout of map-value is a configuration interface.
6551	* New members can only be added to the end of this structure.
6552	*/
6553	struct bpf_cpumap_val {
6554	__u32 qsize; / queue size to remote target CPU /
6555	union {
6556	int fd; / prog fd on map write /
6557	__u32 id; / prog id on map read /
6558	} bpf_prog;
6559	};
6560
6561	enum sk_action {
6562	SK_DROP = `0`,
6563	SK_PASS,
6564	};
6565
6566	/ user accessible metadata for SK_MSG packet hook, new fields must*
6567	* be added to the end of this structure
6568	*/
6569	struct sk_msg_md {
6570	__bpf_md_ptr(void *, data);
6571	__bpf_md_ptr(void *, data_end);
6572
6573	__u32 family;
6574	__u32 remote_ip4; / Stored in network byte order /
6575	__u32 local_ip4; / Stored in network byte order /
6576	__u32 remote_ip6[`4`]; / Stored in network byte order /
6577	__u32 local_ip6[`4`]; / Stored in network byte order /
6578	__u32 remote_port; / Stored in network byte order /
6579	__u32 local_port; / stored in host byte order /
6580	__u32 size; / Total size of sk_msg /
6581
6582	__bpf_md_ptr(struct bpf_sock , sk); /* current socket /
6583	};
6584
6585	struct sk_reuseport_md {
6586	/*
6587	* Start of directly accessible data. It begins from
6588	* the tcp/udp header.
6589	*/
6590	__bpf_md_ptr(void *, data);
6591	/ End of directly accessible data /
6592	__bpf_md_ptr(void *, data_end);
6593	/*
6594	* Total length of packet (starting from the tcp/udp header).
6595	* Note that the directly accessible bytes (data_end - data)
6596	* could be less than this "len". Those bytes could be
6597	* indirectly read by a helper "bpf_skb_load_bytes()".
6598	*/
6599	__u32 len;
6600	/*
6601	* Eth protocol in the mac header (network byte order). e.g.
6602	* ETH_P_IP(0x0800) and ETH_P_IPV6(0x86DD)
6603	*/
6604	__u32 eth_protocol;
6605	__u32 ip_protocol; / IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP /
6606	__u32 bind_inany; / Is sock bound to an INANY address? /
6607	__u32 hash; / A hash of the packet 4 tuples /
6608	/ When reuse->migrating_sk is NULL, it is selecting a sk for the*
6609	* new incoming connection request (e.g. selecting a listen sk for
6610	* the received SYN in the TCP case). reuse->sk is one of the sk
6611	* in the reuseport group. The bpf prog can use reuse->sk to learn
6612	* the local listening ip/port without looking into the skb.
6613	*
6614	* When reuse->migrating_sk is not NULL, reuse->sk is closed and
6615	* reuse->migrating_sk is the socket that needs to be migrated
6616	* to another listening socket. migrating_sk could be a fullsock
6617	* sk that is fully established or a reqsk that is in-the-middle
6618	* of 3-way handshake.
6619	*/
6620	__bpf_md_ptr(struct bpf_sock *, sk);
6621	__bpf_md_ptr(struct bpf_sock *, migrating_sk);
6622	};
6623
6624	#define BPF_TAG_SIZE 8
6625
6626	struct bpf_prog_info {
6627	__u32 type;
6628	__u32 id;
6629	__u8 tag[BPF_TAG_SIZE];
6630	__u32 jited_prog_len;
6631	__u32 xlated_prog_len;
6632	__aligned_u64 jited_prog_insns;
6633	__aligned_u64 xlated_prog_insns;
6634	__u64 load_time; / ns since boottime /
6635	__u32 created_by_uid;
6636	__u32 nr_map_ids;
6637	__aligned_u64 map_ids;
6638	char name[BPF_OBJ_NAME_LEN];
6639	__u32 ifindex;
6640	__u32 gpl_compatible:`1`;
6641	__u32 :`31`; / alignment pad /
6642	__u64 netns_dev;
6643	__u64 netns_ino;
6644	__u32 nr_jited_ksyms;
6645	__u32 nr_jited_func_lens;
6646	__aligned_u64 jited_ksyms;
6647	__aligned_u64 jited_func_lens;
6648	__u32 btf_id;
6649	__u32 func_info_rec_size;
6650	__aligned_u64 func_info;
6651	__u32 nr_func_info;
6652	__u32 nr_line_info;
6653	__aligned_u64 line_info;
6654	__aligned_u64 jited_line_info;
6655	__u32 nr_jited_line_info;
6656	__u32 line_info_rec_size;
6657	__u32 jited_line_info_rec_size;
6658	__u32 nr_prog_tags;
6659	__aligned_u64 prog_tags;
6660	__u64 run_time_ns;
6661	__u64 run_cnt;
6662	__u64 recursion_misses;
6663	__u32 verified_insns;
6664	__u32 attach_btf_obj_id;
6665	__u32 attach_btf_id;
6666	} __attribute__((aligned(`8`)));
6667
6668	struct bpf_map_info {
6669	__u32 type;
6670	__u32 id;
6671	__u32 key_size;
6672	__u32 value_size;
6673	__u32 max_entries;
6674	__u32 map_flags;
6675	char name[BPF_OBJ_NAME_LEN];
6676	__u32 ifindex;
6677	__u32 btf_vmlinux_value_type_id;
6678	__u64 netns_dev;
6679	__u64 netns_ino;
6680	__u32 btf_id;
6681	__u32 btf_key_type_id;
6682	__u32 btf_value_type_id;
6683	__u32 btf_vmlinux_id;
6684	__u64 map_extra;
6685	__aligned_u64 hash;
6686	__u32 hash_size;
6687	} __attribute__((aligned(`8`)));
6688
6689	struct bpf_btf_info {
6690	__aligned_u64 btf;
6691	__u32 btf_size;
6692	__u32 id;
6693	__aligned_u64 name;
6694	__u32 name_len;
6695	__u32 kernel_btf;
6696	} __attribute__((aligned(`8`)));
6697
6698	struct bpf_link_info {
6699	__u32 type;
6700	__u32 id;
6701	__u32 prog_id;
6702	union {
6703	struct {
6704	__aligned_u64 tp_name; / in/out: tp_name buffer ptr /
6705	__u32 tp_name_len; / in/out: tp_name buffer len /
6706	__u32 :`32`;
6707	__u64 cookie;
6708	} raw_tracepoint;
6709	struct {
6710	__u32 attach_type;
6711	__u32 target_obj_id; / prog_id for PROG_EXT, otherwise btf object id /
6712	__u32 target_btf_id; / BTF type id inside the object /
6713	__u32 :`32`;
6714	__u64 cookie;
6715	} tracing;
6716	struct {
6717	__u64 cgroup_id;
6718	__u32 attach_type;
6719	} cgroup;
6720	struct {
6721	__aligned_u64 target_name; / in/out: target_name buffer ptr /
6722	__u32 target_name_len; / in/out: target_name buffer len /
6723
6724	/ If the iter specific field is 32 bits, it can be put*
6725	* in the first or second union. Otherwise it should be
6726	* put in the second union.
6727	*/
6728	union {
6729	struct {
6730	__u32 map_id;
6731	} map;
6732	};
6733	union {
6734	struct {
6735	__u64 cgroup_id;
6736	__u32 order;
6737	} cgroup;
6738	struct {
6739	__u32 tid;
6740	__u32 pid;
6741	} task;
6742	};
6743	} iter;
6744	struct {
6745	__u32 netns_ino;
6746	__u32 attach_type;
6747	} netns;
6748	struct {
6749	__u32 ifindex;
6750	} xdp;
6751	struct {
6752	__u32 map_id;
6753	} struct_ops;
6754	struct {
6755	__u32 pf;
6756	__u32 hooknum;
6757	__s32 priority;
6758	__u32 flags;
6759	} netfilter;
6760	struct {
6761	__aligned_u64 addrs;
6762	__u32 count; / in/out: kprobe_multi function count /
6763	__u32 flags;
6764	__u64 missed;
6765	__aligned_u64 cookies;
6766	} kprobe_multi;
6767	struct {
6768	__aligned_u64 path;
6769	__aligned_u64 offsets;
6770	__aligned_u64 ref_ctr_offsets;
6771	__aligned_u64 cookies;
6772	__u32 path_size; / in/out: real path size on success, including zero byte /
6773	__u32 count; / in/out: uprobe_multi offsets/ref_ctr_offsets/cookies count /
6774	__u32 flags;
6775	__u32 pid;
6776	} uprobe_multi;
6777	struct {
6778	__u32 type; / enum bpf_perf_event_type /
6779	__u32 :`32`;
6780	union {
6781	struct {
6782	__aligned_u64 file_name; / in/out /
6783	__u32 name_len;
6784	__u32 offset; / offset from file_name /
6785	__u64 cookie;
6786	__u64 ref_ctr_offset;
6787	} uprobe; / BPF_PERF_EVENT_UPROBE, BPF_PERF_EVENT_URETPROBE /
6788	struct {
6789	__aligned_u64 func_name; / in/out /
6790	__u32 name_len;
6791	__u32 offset; / offset from func_name /
6792	__u64 addr;
6793	__u64 missed;
6794	__u64 cookie;
6795	} kprobe; / BPF_PERF_EVENT_KPROBE, BPF_PERF_EVENT_KRETPROBE /
6796	struct {
6797	__aligned_u64 tp_name; / in/out /
6798	__u32 name_len;
6799	__u32 :`32`;
6800	__u64 cookie;
6801	} tracepoint; / BPF_PERF_EVENT_TRACEPOINT /
6802	struct {
6803	__u64 config;
6804	__u32 type;
6805	__u32 :`32`;
6806	__u64 cookie;
6807	} event; / BPF_PERF_EVENT_EVENT /
6808	};
6809	} perf_event;
6810	struct {
6811	__u32 ifindex;
6812	__u32 attach_type;
6813	} tcx;
6814	struct {
6815	__u32 ifindex;
6816	__u32 attach_type;
6817	} netkit;
6818	struct {
6819	__u32 map_id;
6820	__u32 attach_type;
6821	} sockmap;
6822	};
6823	} __attribute__((aligned(`8`)));
6824
6825	struct bpf_token_info {
6826	__u64 allowed_cmds;
6827	__u64 allowed_maps;
6828	__u64 allowed_progs;
6829	__u64 allowed_attachs;
6830	} __attribute__((aligned(`8`)));
6831
6832	/ User bpf_sock_addr struct to access socket fields and sockaddr struct passed*
6833	* by user and intended to be used by socket (e.g. to bind to, depends on
6834	* attach type).
6835	*/
6836	struct bpf_sock_addr {
6837	__u32 user_family; / Allows 4-byte read, but no write. /
6838	__u32 user_ip4; / Allows 1,2,4-byte read and 4-byte write.*
6839	* Stored in network byte order.
6840	*/
6841	__u32 user_ip6[`4`]; / Allows 1,2,4,8-byte read and 4,8-byte write.*
6842	* Stored in network byte order.
6843	*/
6844	__u32 user_port; / Allows 1,2,4-byte read and 4-byte write.*
6845	* Stored in network byte order
6846	*/
6847	__u32 family; / Allows 4-byte read, but no write /
6848	__u32 type; / Allows 4-byte read, but no write /
6849	__u32 protocol; / Allows 4-byte read, but no write /
6850	__u32 msg_src_ip4; / Allows 1,2,4-byte read and 4-byte write.*
6851	* Stored in network byte order.
6852	*/
6853	__u32 msg_src_ip6[`4`]; / Allows 1,2,4,8-byte read and 4,8-byte write.*
6854	* Stored in network byte order.
6855	*/
6856	__bpf_md_ptr(struct bpf_sock *, sk);
6857	};
6858
6859	/ User bpf_sock_ops struct to access socket values and specify request ops*
6860	* and their replies.
6861	* Some of this fields are in network (bigendian) byte order and may need
6862	* to be converted before use (bpf_ntohl() defined in samples/bpf/bpf_endian.h).
6863	* New fields can only be added at the end of this structure
6864	*/
6865	struct bpf_sock_ops {
6866	__u32 op;
6867	union {
6868	__u32 args[`4`]; / Optionally passed to bpf program /
6869	__u32 reply; / Returned by bpf program /
6870	__u32 replylong[`4`]; / Optionally returned by bpf prog /
6871	};
6872	__u32 family;
6873	__u32 remote_ip4; / Stored in network byte order /
6874	__u32 local_ip4; / Stored in network byte order /
6875	__u32 remote_ip6[`4`]; / Stored in network byte order /
6876	__u32 local_ip6[`4`]; / Stored in network byte order /
6877	__u32 remote_port; / Stored in network byte order /
6878	__u32 local_port; / stored in host byte order /
6879	__u32 is_fullsock; / Some TCP fields are only valid if*
6880	* there is a full socket. If not, the
6881	* fields read as zero.
6882	*/
6883	__u32 snd_cwnd;
6884	__u32 srtt_us; / Averaged RTT << 3 in usecs /
6885	__u32 bpf_sock_ops_cb_flags; / flags defined in uapi/linux/tcp.h /
6886	__u32 state;
6887	__u32 rtt_min;
6888	__u32 snd_ssthresh;
6889	__u32 rcv_nxt;
6890	__u32 snd_nxt;
6891	__u32 snd_una;
6892	__u32 mss_cache;
6893	__u32 ecn_flags;
6894	__u32 rate_delivered;
6895	__u32 rate_interval_us;
6896	__u32 packets_out;
6897	__u32 retrans_out;
6898	__u32 total_retrans;
6899	__u32 segs_in;
6900	__u32 data_segs_in;
6901	__u32 segs_out;
6902	__u32 data_segs_out;
6903	__u32 lost_out;
6904	__u32 sacked_out;
6905	__u32 sk_txhash;
6906	__u64 bytes_received;
6907	__u64 bytes_acked;
6908	__bpf_md_ptr(struct bpf_sock *, sk);
6909	/ [skb_data, skb_data_end) covers the whole TCP header.*
6910	*
6911	* BPF_SOCK_OPS_PARSE_HDR_OPT_CB: The packet received
6912	* BPF_SOCK_OPS_HDR_OPT_LEN_CB: Not useful because the
6913	* header has not been written.
6914	* BPF_SOCK_OPS_WRITE_HDR_OPT_CB: The header and options have
6915	* been written so far.
6916	* BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: The SYNACK that concludes
6917	* the 3WHS.
6918	* BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: The ACK that concludes
6919	* the 3WHS.
6920	*
6921	* bpf_load_hdr_opt() can also be used to read a particular option.
6922	*/
6923	__bpf_md_ptr(void *, skb_data);
6924	__bpf_md_ptr(void *, skb_data_end);
6925	__u32 skb_len; / The total length of a packet.*
6926	* It includes the header, options,
6927	* and payload.
6928	*/
6929	__u32 skb_tcp_flags; / tcp_flags of the header. It provides*
6930	* an easy way to check for tcp_flags
6931	* without parsing skb_data.
6932	*
6933	* In particular, the skb_tcp_flags
6934	* will still be available in
6935	* BPF_SOCK_OPS_HDR_OPT_LEN even though
6936	* the outgoing header has not
6937	* been written yet.
6938	*/
6939	__u64 skb_hwtstamp;
6940	};
6941
6942	/ Definitions for bpf_sock_ops_cb_flags /
6943	enum {
6944	BPF_SOCK_OPS_RTO_CB_FLAG = (`1`<<`0`),
6945	BPF_SOCK_OPS_RETRANS_CB_FLAG = (`1`<<`1`),
6946	BPF_SOCK_OPS_STATE_CB_FLAG = (`1`<<`2`),
6947	BPF_SOCK_OPS_RTT_CB_FLAG = (`1`<<`3`),
6948	/ Call bpf for all received TCP headers. The bpf prog will be*
6949	* called under sock_ops->op == BPF_SOCK_OPS_PARSE_HDR_OPT_CB
6950	*
6951	* Please refer to the comment in BPF_SOCK_OPS_PARSE_HDR_OPT_CB
6952	* for the header option related helpers that will be useful
6953	* to the bpf programs.
6954	*
6955	* It could be used at the client/active side (i.e. connect() side)
6956	* when the server told it that the server was in syncookie
6957	* mode and required the active side to resend the bpf-written
6958	* options. The active side can keep writing the bpf-options until
6959	* it received a valid packet from the server side to confirm
6960	* the earlier packet (and options) has been received. The later
6961	* example patch is using it like this at the active side when the
6962	* server is in syncookie mode.
6963	*
6964	* The bpf prog will usually turn this off in the common cases.
6965	*/
6966	BPF_SOCK_OPS_PARSE_ALL_HDR_OPT_CB_FLAG = (`1`<<`4`),
6967	/ Call bpf when kernel has received a header option that*
6968	* the kernel cannot handle. The bpf prog will be called under
6969	* sock_ops->op == BPF_SOCK_OPS_PARSE_HDR_OPT_CB.
6970	*
6971	* Please refer to the comment in BPF_SOCK_OPS_PARSE_HDR_OPT_CB
6972	* for the header option related helpers that will be useful
6973	* to the bpf programs.
6974	*/
6975	BPF_SOCK_OPS_PARSE_UNKNOWN_HDR_OPT_CB_FLAG = (`1`<<`5`),
6976	/ Call bpf when the kernel is writing header options for the*
6977	* outgoing packet. The bpf prog will first be called
6978	* to reserve space in a skb under
6979	* sock_ops->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB. Then
6980	* the bpf prog will be called to write the header option(s)
6981	* under sock_ops->op == BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
6982	*
6983	* Please refer to the comment in BPF_SOCK_OPS_HDR_OPT_LEN_CB
6984	* and BPF_SOCK_OPS_WRITE_HDR_OPT_CB for the header option
6985	* related helpers that will be useful to the bpf programs.
6986	*
6987	* The kernel gets its chance to reserve space and write
6988	* options first before the BPF program does.
6989	*/
6990	BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG = (`1`<<`6`),
6991	/ Mask of all currently supported cb flags /
6992	BPF_SOCK_OPS_ALL_CB_FLAGS = `0x7F`,
6993	};
6994
6995	enum {
6996	SK_BPF_CB_TX_TIMESTAMPING = `1`<<`0`,
6997	SK_BPF_CB_MASK = (SK_BPF_CB_TX_TIMESTAMPING - `1`) \|
6998	SK_BPF_CB_TX_TIMESTAMPING
6999	};
7000
7001	/ List of known BPF sock_ops operators.*
7002	* New entries can only be added at the end
7003	*/
7004	enum {
7005	BPF_SOCK_OPS_VOID,
7006	BPF_SOCK_OPS_TIMEOUT_INIT, / Should return SYN-RTO value to use or*
7007	* -1 if default value should be used
7008	*/
7009	BPF_SOCK_OPS_RWND_INIT, / Should return initial advertized*
7010	* window (in packets) or -1 if default
7011	* value should be used
7012	*/
7013	BPF_SOCK_OPS_TCP_CONNECT_CB, / Calls BPF program right before an*
7014	* active connection is initialized
7015	*/
7016	BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB, / Calls BPF program when an*
7017	* active connection is
7018	* established
7019	*/
7020	BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, / Calls BPF program when a*
7021	* passive connection is
7022	* established
7023	*/
7024	BPF_SOCK_OPS_NEEDS_ECN, / If connection's congestion control*
7025	* needs ECN
7026	*/
7027	BPF_SOCK_OPS_BASE_RTT, / Get base RTT. The correct value is*
7028	* based on the path and may be
7029	* dependent on the congestion control
7030	* algorithm. In general it indicates
7031	* a congestion threshold. RTTs above
7032	* this indicate congestion
7033	*/
7034	BPF_SOCK_OPS_RTO_CB, / Called when an RTO has triggered.*
7035	* Arg1: value of icsk_retransmits
7036	* Arg2: value of icsk_rto
7037	* Arg3: whether RTO has expired
7038	*/
7039	BPF_SOCK_OPS_RETRANS_CB, / Called when skb is retransmitted.*
7040	* Arg1: sequence number of 1st byte
7041	* Arg2: # segments
7042	* Arg3: return value of
7043	* tcp_transmit_skb (0 => success)
7044	*/
7045	BPF_SOCK_OPS_STATE_CB, / Called when TCP changes state.*
7046	* Arg1: old_state
7047	* Arg2: new_state
7048	*/
7049	BPF_SOCK_OPS_TCP_LISTEN_CB, / Called on listen(2), right after*
7050	* socket transition to LISTEN state.
7051	*/
7052	BPF_SOCK_OPS_RTT_CB, / Called on every RTT.*
7053	* Arg1: measured RTT input (mrtt)
7054	* Arg2: updated srtt
7055	*/
7056	BPF_SOCK_OPS_PARSE_HDR_OPT_CB, / Parse the header option.*
7057	* It will be called to handle
7058	* the packets received at
7059	* an already established
7060	* connection.
7061	*
7062	* sock_ops->skb_data:
7063	* Referring to the received skb.
7064	* It covers the TCP header only.
7065	*
7066	* bpf_load_hdr_opt() can also
7067	* be used to search for a
7068	* particular option.
7069	*/
7070	BPF_SOCK_OPS_HDR_OPT_LEN_CB, / Reserve space for writing the*
7071	* header option later in
7072	* BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
7073	* Arg1: bool want_cookie. (in
7074	* writing SYNACK only)
7075	*
7076	* sock_ops->skb_data:
7077	* Not available because no header has
7078	* been written yet.
7079	*
7080	* sock_ops->skb_tcp_flags:
7081	* The tcp_flags of the
7082	* outgoing skb. (e.g. SYN, ACK, FIN).
7083	*
7084	* bpf_reserve_hdr_opt() should
7085	* be used to reserve space.
7086	*/
7087	BPF_SOCK_OPS_WRITE_HDR_OPT_CB, / Write the header options*
7088	* Arg1: bool want_cookie. (in
7089	* writing SYNACK only)
7090	*
7091	* sock_ops->skb_data:
7092	* Referring to the outgoing skb.
7093	* It covers the TCP header
7094	* that has already been written
7095	* by the kernel and the
7096	* earlier bpf-progs.
7097	*
7098	* sock_ops->skb_tcp_flags:
7099	* The tcp_flags of the outgoing
7100	* skb. (e.g. SYN, ACK, FIN).
7101	*
7102	* bpf_store_hdr_opt() should
7103	* be used to write the
7104	* option.
7105	*
7106	* bpf_load_hdr_opt() can also
7107	* be used to search for a
7108	* particular option that
7109	* has already been written
7110	* by the kernel or the
7111	* earlier bpf-progs.
7112	*/
7113	BPF_SOCK_OPS_TSTAMP_SCHED_CB, / Called when skb is passing*
7114	* through dev layer when
7115	* SK_BPF_CB_TX_TIMESTAMPING
7116	* feature is on.
7117	*/
7118	BPF_SOCK_OPS_TSTAMP_SND_SW_CB, / Called when skb is about to send*
7119	* to the nic when SK_BPF_CB_TX_TIMESTAMPING
7120	* feature is on.
7121	*/
7122	BPF_SOCK_OPS_TSTAMP_SND_HW_CB, / Called in hardware phase when*
7123	* SK_BPF_CB_TX_TIMESTAMPING feature
7124	* is on.
7125	*/
7126	BPF_SOCK_OPS_TSTAMP_ACK_CB, / Called when all the skbs in the*
7127	* same sendmsg call are acked
7128	* when SK_BPF_CB_TX_TIMESTAMPING
7129	* feature is on.
7130	*/
7131	BPF_SOCK_OPS_TSTAMP_SENDMSG_CB, / Called when every sendmsg syscall*
7132	* is triggered. It's used to correlate
7133	* sendmsg timestamp with corresponding
7134	* tskey.
7135	*/
7136	};
7137
7138	/ List of TCP states. There is a build check in net/ipv4/tcp.c to detect*
7139	* changes between the TCP and BPF versions. Ideally this should never happen.
7140	* If it does, we need to add code to convert them before calling
7141	* the BPF sock_ops function.
7142	*/
7143	enum {
7144	BPF_TCP_ESTABLISHED = `1`,
7145	BPF_TCP_SYN_SENT,
7146	BPF_TCP_SYN_RECV,
7147	BPF_TCP_FIN_WAIT1,
7148	BPF_TCP_FIN_WAIT2,
7149	BPF_TCP_TIME_WAIT,
7150	BPF_TCP_CLOSE,
7151	BPF_TCP_CLOSE_WAIT,
7152	BPF_TCP_LAST_ACK,
7153	BPF_TCP_LISTEN,
7154	BPF_TCP_CLOSING, / Now a valid state /
7155	BPF_TCP_NEW_SYN_RECV,
7156	BPF_TCP_BOUND_INACTIVE,
7157
7158	BPF_TCP_MAX_STATES / Leave at the end! /
7159	};
7160
7161	enum {
7162	TCP_BPF_IW = `1001`, / Set TCP initial congestion window /
7163	TCP_BPF_SNDCWND_CLAMP = `1002`, / Set sndcwnd_clamp /
7164	TCP_BPF_DELACK_MAX = `1003`, / Max delay ack in usecs /
7165	TCP_BPF_RTO_MIN = `1004`, / Min delay ack in usecs /
7166	/ Copy the SYN pkt to optval*
7167	*
7168	* BPF_PROG_TYPE_SOCK_OPS only. It is similar to the
7169	* bpf_getsockopt(TCP_SAVED_SYN) but it does not limit
7170	* to only getting from the saved_syn. It can either get the
7171	* syn packet from:
7172	*
7173	* 1. the just-received SYN packet (only available when writing the
7174	* SYNACK). It will be useful when it is not necessary to
7175	* save the SYN packet for latter use. It is also the only way
7176	* to get the SYN during syncookie mode because the syn
7177	* packet cannot be saved during syncookie.
7178	*
7179	* OR
7180	*
7181	* 2. the earlier saved syn which was done by
7182	* bpf_setsockopt(TCP_SAVE_SYN).
7183	*
7184	* The bpf_getsockopt(TCP_BPF_SYN*) option will hide where the
7185	* SYN packet is obtained.
7186	*
7187	* If the bpf-prog does not need the IP[46] header, the
7188	* bpf-prog can avoid parsing the IP header by using
7189	* TCP_BPF_SYN. Otherwise, the bpf-prog can get both
7190	* IP[46] and TCP header by using TCP_BPF_SYN_IP.
7191	*
7192	* >0: Total number of bytes copied
7193	* -ENOSPC: Not enough space in optval. Only optlen number of
7194	* bytes is copied.
7195	* -ENOENT: The SYN skb is not available now and the earlier SYN pkt
7196	* is not saved by setsockopt(TCP_SAVE_SYN).
7197	*/
7198	TCP_BPF_SYN = `1005`, / Copy the TCP header /
7199	TCP_BPF_SYN_IP = `1006`, / Copy the IP[46] and TCP header /
7200	TCP_BPF_SYN_MAC = `1007`, / Copy the MAC, IP[46], and TCP header /
7201	TCP_BPF_SOCK_OPS_CB_FLAGS = `1008`, / Get or Set TCP sock ops flags /
7202	SK_BPF_CB_FLAGS = `1009`, / Get or set sock ops flags in socket /
7203	};
7204
7205	enum {
7206	BPF_LOAD_HDR_OPT_TCP_SYN = (`1ULL` << `0`),
7207	};
7208
7209	/ args[0] value during BPF_SOCK_OPS_HDR_OPT_LEN_CB and*
7210	* BPF_SOCK_OPS_WRITE_HDR_OPT_CB.
7211	*/
7212	enum {
7213	BPF_WRITE_HDR_TCP_CURRENT_MSS = `1`, / Kernel is finding the*
7214	* total option spaces
7215	* required for an established
7216	* sk in order to calculate the
7217	* MSS. No skb is actually
7218	* sent.
7219	*/
7220	BPF_WRITE_HDR_TCP_SYNACK_COOKIE = `2`, / Kernel is in syncookie mode*
7221	* when sending a SYN.
7222	*/
7223	};
7224
7225	struct bpf_perf_event_value {
7226	__u64 counter;
7227	__u64 enabled;
7228	__u64 running;
7229	};
7230
7231	enum {
7232	BPF_DEVCG_ACC_MKNOD = (`1ULL` << `0`),
7233	BPF_DEVCG_ACC_READ = (`1ULL` << `1`),
7234	BPF_DEVCG_ACC_WRITE = (`1ULL` << `2`),
7235	};
7236
7237	enum {
7238	BPF_DEVCG_DEV_BLOCK = (`1ULL` << `0`),
7239	BPF_DEVCG_DEV_CHAR = (`1ULL` << `1`),
7240	};
7241
7242	struct bpf_cgroup_dev_ctx {
7243	/ access_type encoded as (BPF_DEVCG_ACC_* << 16) \| BPF_DEVCG_DEV_* /
7244	__u32 access_type;
7245	__u32 major;
7246	__u32 minor;
7247	};
7248
7249	struct bpf_raw_tracepoint_args {
7250	__u64 args[`0`];
7251	};
7252
7253	/ DIRECT: Skip the FIB rules and go to FIB table associated with device*
7254	* OUTPUT: Do lookup from egress perspective; default is ingress
7255	*/
7256	enum {
7257	BPF_FIB_LOOKUP_DIRECT = (`1U` << `0`),
7258	BPF_FIB_LOOKUP_OUTPUT = (`1U` << `1`),
7259	BPF_FIB_LOOKUP_SKIP_NEIGH = (`1U` << `2`),
7260	BPF_FIB_LOOKUP_TBID = (`1U` << `3`),
7261	BPF_FIB_LOOKUP_SRC = (`1U` << `4`),
7262	BPF_FIB_LOOKUP_MARK = (`1U` << `5`),
7263	};
7264
7265	enum {
7266	BPF_FIB_LKUP_RET_SUCCESS, / lookup successful /
7267	BPF_FIB_LKUP_RET_BLACKHOLE, / dest is blackholed; can be dropped /
7268	BPF_FIB_LKUP_RET_UNREACHABLE, / dest is unreachable; can be dropped /
7269	BPF_FIB_LKUP_RET_PROHIBIT, / dest not allowed; can be dropped /
7270	BPF_FIB_LKUP_RET_NOT_FWDED, / packet is not forwarded /
7271	BPF_FIB_LKUP_RET_FWD_DISABLED, / fwding is not enabled on ingress /
7272	BPF_FIB_LKUP_RET_UNSUPP_LWT, / fwd requires encapsulation /
7273	BPF_FIB_LKUP_RET_NO_NEIGH, / no neighbor entry for nh /
7274	BPF_FIB_LKUP_RET_FRAG_NEEDED, / fragmentation required to fwd /
7275	BPF_FIB_LKUP_RET_NO_SRC_ADDR, / failed to derive IP src addr /
7276	};
7277
7278	struct bpf_fib_lookup {
7279	/ input: network family for lookup (AF_INET, AF_INET6)*
7280	* output: network family of egress nexthop
7281	*/
7282	__u8 family;
7283
7284	/ set if lookup is to consider L4 data - e.g., FIB rules /
7285	__u8 l4_protocol;
7286	__be16 sport;
7287	__be16 dport;
7288
7289	union { / used for MTU check /
7290	/ input to lookup /
7291	__u16 tot_len; / L3 length from network hdr (iph->tot_len) /
7292
7293	/ output: MTU value /
7294	__u16 mtu_result;
7295	} __attribute__((packed, aligned(`2`)));
7296	/ input: L3 device index for lookup*
7297	* output: device index from FIB lookup
7298	*/
7299	__u32 ifindex;
7300
7301	union {
7302	/ inputs to lookup /
7303	__u8 tos; / AF_INET /
7304	__be32 flowinfo; / AF_INET6, flow_label + priority /
7305
7306	/ output: metric of fib result (IPv4/IPv6 only) /
7307	__u32 rt_metric;
7308	};
7309
7310	/ input: source address to consider for lookup*
7311	* output: source address result from lookup
7312	*/
7313	union {
7314	__be32 ipv4_src;
7315	__u32 ipv6_src[`4`]; / in6_addr; network order /
7316	};
7317
7318	/ input to bpf_fib_lookup, ipv{4,6}_dst is destination address in*
7319	* network header. output: bpf_fib_lookup sets to gateway address
7320	* if FIB lookup returns gateway route
7321	*/
7322	union {
7323	__be32 ipv4_dst;
7324	__u32 ipv6_dst[`4`]; / in6_addr; network order /
7325	};
7326
7327	union {
7328	struct {
7329	/ output /
7330	__be16 h_vlan_proto;
7331	__be16 h_vlan_TCI;
7332	};
7333	/ input: when accompanied with the*
7334	* 'BPF_FIB_LOOKUP_DIRECT \| BPF_FIB_LOOKUP_TBID` flags, a
7335	* specific routing table to use for the fib lookup.
7336	*/
7337	__u32 tbid;
7338	};
7339
7340	union {
7341	/ input /
7342	struct {
7343	__u32 mark; / policy routing /
7344	/ 2 4-byte holes for input /
7345	};
7346
7347	/ output: source and dest mac /
7348	struct {
7349	__u8 smac[`6`]; / ETH_ALEN /
7350	__u8 dmac[`6`]; / ETH_ALEN /
7351	};
7352	};
7353	};
7354
7355	struct bpf_redir_neigh {
7356	/ network family for lookup (AF_INET, AF_INET6) /
7357	__u32 nh_family;
7358	/ network address of nexthop; skips fib lookup to find gateway /
7359	union {
7360	__be32 ipv4_nh;
7361	__u32 ipv6_nh[`4`]; / in6_addr; network order /
7362	};
7363	};
7364
7365	/ bpf_check_mtu flags/
7366	enum bpf_check_mtu_flags {
7367	BPF_MTU_CHK_SEGS = (`1U` << `0`),
7368	};
7369
7370	enum bpf_check_mtu_ret {
7371	BPF_MTU_CHK_RET_SUCCESS, / check and lookup successful /
7372	BPF_MTU_CHK_RET_FRAG_NEEDED, / fragmentation required to fwd /
7373	BPF_MTU_CHK_RET_SEGS_TOOBIG, / GSO re-segmentation needed to fwd /
7374	};
7375
7376	enum bpf_task_fd_type {
7377	BPF_FD_TYPE_RAW_TRACEPOINT, / tp name /
7378	BPF_FD_TYPE_TRACEPOINT, / tp name /
7379	BPF_FD_TYPE_KPROBE, / (symbol + offset) or addr /
7380	BPF_FD_TYPE_KRETPROBE, / (symbol + offset) or addr /
7381	BPF_FD_TYPE_UPROBE, / filename + offset /
7382	BPF_FD_TYPE_URETPROBE, / filename + offset /
7383	};
7384
7385	enum {
7386	BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG = (`1U` << `0`),
7387	BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL = (`1U` << `1`),
7388	BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP = (`1U` << `2`),
7389	};
7390
7391	struct bpf_flow_keys {
7392	__u16 nhoff;
7393	__u16 thoff;
7394	__u16 addr_proto; / ETH_P_* of valid addrs /
7395	__u8 is_frag;
7396	__u8 is_first_frag;
7397	__u8 is_encap;
7398	__u8 ip_proto;
7399	__be16 n_proto;
7400	__be16 sport;
7401	__be16 dport;
7402	union {
7403	struct {
7404	__be32 ipv4_src;
7405	__be32 ipv4_dst;
7406	};
7407	struct {
7408	__u32 ipv6_src[`4`]; / in6_addr; network order /
7409	__u32 ipv6_dst[`4`]; / in6_addr; network order /
7410	};
7411	};
7412	__u32 flags;
7413	__be32 flow_label;
7414	};
7415
7416	struct bpf_func_info {
7417	__u32 insn_off;
7418	__u32 type_id;
7419	};
7420
7421	#define BPF_LINE_INFO_LINE_NUM(line_col) ((line_col) >> 10)
7422	#define BPF_LINE_INFO_LINE_COL(line_col) ((line_col) & 0x3ff)
7423
7424	struct bpf_line_info {
7425	__u32 insn_off;
7426	__u32 file_name_off;
7427	__u32 line_off;
7428	__u32 line_col;
7429	};
7430
7431	struct bpf_spin_lock {
7432	__u32 val;
7433	};
7434
7435	struct bpf_timer {
7436	__u64 __opaque[`2`];
7437	} __attribute__((aligned(`8`)));
7438
7439	struct bpf_task_work {
7440	__u64 __opaque;
7441	} __attribute__((aligned(`8`)));
7442
7443	struct bpf_wq {
7444	__u64 __opaque[`2`];
7445	} __attribute__((aligned(`8`)));
7446
7447	struct bpf_dynptr {
7448	__u64 __opaque[`2`];
7449	} __attribute__((aligned(`8`)));
7450
7451	struct bpf_list_head {
7452	__u64 __opaque[`2`];
7453	} __attribute__((aligned(`8`)));
7454
7455	struct bpf_list_node {
7456	__u64 __opaque[`3`];
7457	} __attribute__((aligned(`8`)));
7458
7459	struct bpf_rb_root {
7460	__u64 __opaque[`2`];
7461	} __attribute__((aligned(`8`)));
7462
7463	struct bpf_rb_node {
7464	__u64 __opaque[`4`];
7465	} __attribute__((aligned(`8`)));
7466
7467	struct bpf_refcount {
7468	__u32 __opaque[`1`];
7469	} __attribute__((aligned(`4`)));
7470
7471	struct bpf_sysctl {
7472	__u32 write; / Sysctl is being read (= 0) or written (= 1).*
7473	* Allows 1,2,4-byte read, but no write.
7474	*/
7475	__u32 file_pos; / Sysctl file position to read from, write to.*
7476	* Allows 1,2,4-byte read an 4-byte write.
7477	*/
7478	};
7479
7480	struct bpf_sockopt {
7481	__bpf_md_ptr(struct bpf_sock *, sk);
7482	__bpf_md_ptr(void *, optval);
7483	__bpf_md_ptr(void *, optval_end);
7484
7485	__s32 level;
7486	__s32 optname;
7487	__s32 optlen;
7488	__s32 retval;
7489	};
7490
7491	struct bpf_pidns_info {
7492	__u32 pid;
7493	__u32 tgid;
7494	};
7495
7496	/ User accessible data for SK_LOOKUP programs. Add new fields at the end. /
7497	struct bpf_sk_lookup {
7498	union {
7499	__bpf_md_ptr(struct bpf_sock , sk); /* Selected socket /
7500	__u64 cookie; / Non-zero if socket was selected in PROG_TEST_RUN /
7501	};
7502
7503	__u32 family; / Protocol family (AF_INET, AF_INET6) /
7504	__u32 protocol; / IP protocol (IPPROTO_TCP, IPPROTO_UDP) /
7505	__u32 remote_ip4; / Network byte order /
7506	__u32 remote_ip6[`4`]; / Network byte order /
7507	__be16 remote_port; / Network byte order /
7508	__u16 :`16`; / Zero padding /
7509	__u32 local_ip4; / Network byte order /
7510	__u32 local_ip6[`4`]; / Network byte order /
7511	__u32 local_port; / Host byte order /
7512	__u32 ingress_ifindex; / The arriving interface. Determined by inet_iif. /
7513	};
7514
7515	/*
7516	* struct btf_ptr is used for typed pointer representation; the
7517	* type id is used to render the pointer data as the appropriate type
7518	* via the bpf_snprintf_btf() helper described above. A flags field -
7519	* potentially to specify additional details about the BTF pointer
7520	* (rather than its mode of display) - is included for future use.
7521	* Display flags - BTF_F_* - are passed to bpf_snprintf_btf separately.
7522	*/
7523	struct btf_ptr {
7524	void *ptr;
7525	__u32 type_id;
7526	__u32 flags; / BTF ptr flags; unused at present. /
7527	};
7528
7529	/*
7530	* Flags to control bpf_snprintf_btf() behaviour.
7531	* - BTF_F_COMPACT: no formatting around type information
7532	* - BTF_F_NONAME: no struct/union member names/types
7533	* - BTF_F_PTR_RAW: show raw (unobfuscated) pointer values;
7534	* equivalent to %px.
7535	* - BTF_F_ZERO: show zero-valued struct/union members; they
7536	* are not displayed by default
7537	*/
7538	enum {
7539	BTF_F_COMPACT = (`1ULL` << `0`),
7540	BTF_F_NONAME = (`1ULL` << `1`),
7541	BTF_F_PTR_RAW = (`1ULL` << `2`),
7542	BTF_F_ZERO = (`1ULL` << `3`),
7543	};
7544
7545	/ bpf_core_relo_kind encodes which aspect of captured field/type/enum value*
7546	* has to be adjusted by relocations. It is emitted by llvm and passed to
7547	* libbpf and later to the kernel.
7548	*/
7549	enum bpf_core_relo_kind {
7550	BPF_CORE_FIELD_BYTE_OFFSET = `0`, / field byte offset /
7551	BPF_CORE_FIELD_BYTE_SIZE = `1`, / field size in bytes /
7552	BPF_CORE_FIELD_EXISTS = `2`, / field existence in target kernel /
7553	BPF_CORE_FIELD_SIGNED = `3`, / field signedness (0 - unsigned, 1 - signed) /
7554	BPF_CORE_FIELD_LSHIFT_U64 = `4`, / bitfield-specific left bitshift /
7555	BPF_CORE_FIELD_RSHIFT_U64 = `5`, / bitfield-specific right bitshift /
7556	BPF_CORE_TYPE_ID_LOCAL = `6`, / type ID in local BPF object /
7557	BPF_CORE_TYPE_ID_TARGET = `7`, / type ID in target kernel /
7558	BPF_CORE_TYPE_EXISTS = `8`, / type existence in target kernel /
7559	BPF_CORE_TYPE_SIZE = `9`, / type size in bytes /
7560	BPF_CORE_ENUMVAL_EXISTS = `10`, / enum value existence in target kernel /
7561	BPF_CORE_ENUMVAL_VALUE = `11`, / enum value integer value /
7562	BPF_CORE_TYPE_MATCHES = `12`, / type match in target kernel /
7563	};
7564
7565	/*
7566	* "struct bpf_core_relo" is used to pass relocation data form LLVM to libbpf
7567	* and from libbpf to the kernel.
7568	*
7569	* CO-RE relocation captures the following data:
7570	* - insn_off - instruction offset (in bytes) within a BPF program that needs
7571	* its insn->imm field to be relocated with actual field info;
7572	* - type_id - BTF type ID of the "root" (containing) entity of a relocatable
7573	* type or field;
7574	* - access_str_off - offset into corresponding .BTF string section. String
7575	* interpretation depends on specific relocation kind:
7576	* - for field-based relocations, string encodes an accessed field using
7577	* a sequence of field and array indices, separated by colon (:). It's
7578	* conceptually very close to LLVM's getelementptr ([0]) instruction's
7579	* arguments for identifying offset to a field.
7580	* - for type-based relocations, strings is expected to be just "0";
7581	* - for enum value-based relocations, string contains an index of enum
7582	* value within its enum type;
7583	* - kind - one of enum bpf_core_relo_kind;
7584	*
7585	* Example:
7586	* struct sample {
7587	* int a;
7588	* struct {
7589	* int b[10];
7590	* };
7591	* };
7592	*
7593	* struct sample *s = ...;
7594	* int *x = &s->a; // encoded as "0:0" (a is field #0)
7595	* int *y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1,
7596	* // b is field #0 inside anon struct, accessing elem #5)
7597	* int *z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
7598	*
7599	* type_id for all relocs in this example will capture BTF type id of
7600	* `struct sample`.
7601	*
7602	* Such relocation is emitted when using __builtin_preserve_access_index()
7603	* Clang built-in, passing expression that captures field address, e.g.:
7604	*
7605	* bpf_probe_read(&dst, sizeof(dst),
7606	* __builtin_preserve_access_index(&src->a.b.c));
7607	*
7608	* In this case Clang will emit field relocation recording necessary data to
7609	* be able to find offset of embedded `a.b.c` field within `src` struct.
7610	*
7611	* [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction
7612	*/
7613	struct bpf_core_relo {
7614	__u32 insn_off;
7615	__u32 type_id;
7616	__u32 access_str_off;
7617	enum bpf_core_relo_kind kind;
7618	};
7619
7620	/*
7621	* Flags to control bpf_timer_start() behaviour.
7622	* - BPF_F_TIMER_ABS: Timeout passed is absolute time, by default it is
7623	* relative to current time.
7624	* - BPF_F_TIMER_CPU_PIN: Timer will be pinned to the CPU of the caller.
7625	*/
7626	enum {
7627	BPF_F_TIMER_ABS = (`1ULL` << `0`),
7628	BPF_F_TIMER_CPU_PIN = (`1ULL` << `1`),
7629	};
7630
7631	/ BPF numbers iterator state /
7632	struct bpf_iter_num {
7633	/ opaque iterator state; having __u64 here allows to preserve correct*
7634	* alignment requirements in vmlinux.h, generated from BTF
7635	*/
7636	__u64 __opaque[`1`];
7637	} __attribute__((aligned(`8`)));
7638
7639	/*
7640	* Flags to control BPF kfunc behaviour.
7641	* - BPF_F_PAD_ZEROS: Pad destination buffer with zeros. (See the respective
7642	* helper documentation for details.)
7643	*/
7644	enum bpf_kfunc_flags {
7645	BPF_F_PAD_ZEROS = (`1ULL` << `0`),
7646	};
7647
7648	#endif /* _UAPI__LINUX_BPF_H__ */
7649

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