1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * common UDP/RAW code
4 * Linux INET6 implementation
5 *
6 * Authors:
7 * Pedro Roque <roque@di.fc.ul.pt>
8 */
9
10#include <linux/capability.h>
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/interrupt.h>
15#include <linux/socket.h>
16#include <linux/sockios.h>
17#include <linux/in6.h>
18#include <linux/ipv6.h>
19#include <linux/route.h>
20#include <linux/slab.h>
21#include <linux/export.h>
22#include <linux/icmp.h>
23
24#include <net/ipv6.h>
25#include <net/ndisc.h>
26#include <net/addrconf.h>
27#include <net/transp_v6.h>
28#include <net/ip6_route.h>
29#include <net/tcp_states.h>
30#include <net/dsfield.h>
31#include <net/sock_reuseport.h>
32
33#include <linux/errqueue.h>
34#include <linux/uaccess.h>
35
36static bool ipv6_mapped_addr_any(const struct in6_addr *a)
37{
38 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
39}
40
41static void ip6_datagram_flow_key_init(struct flowi6 *fl6,
42 const struct sock *sk)
43{
44 const struct inet_sock *inet = inet_sk(sk);
45 const struct ipv6_pinfo *np = inet6_sk(sk: sk);
46 int oif = sk->sk_bound_dev_if;
47
48 memset(s: fl6, c: 0, n: sizeof(*fl6));
49 fl6->flowi6_proto = sk->sk_protocol;
50 fl6->daddr = sk->sk_v6_daddr;
51 fl6->saddr = np->saddr;
52 fl6->flowi6_mark = sk->sk_mark;
53 fl6->fl6_dport = inet->inet_dport;
54 fl6->fl6_sport = inet->inet_sport;
55 fl6->flowlabel = ip6_make_flowinfo(tclass: np->tclass, flowlabel: np->flow_label);
56 fl6->flowi6_uid = sk_uid(sk);
57
58 if (!oif)
59 oif = np->sticky_pktinfo.ipi6_ifindex;
60
61 if (!oif) {
62 if (ipv6_addr_is_multicast(addr: &fl6->daddr))
63 oif = READ_ONCE(np->mcast_oif);
64 else
65 oif = READ_ONCE(np->ucast_oif);
66 }
67
68 fl6->flowi6_oif = oif;
69 security_sk_classify_flow(sk, flic: flowi6_to_flowi_common(fl6));
70}
71
72int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
73{
74 struct ip6_flowlabel *flowlabel = NULL;
75 struct in6_addr *final_p, final;
76 struct ipv6_txoptions *opt;
77 struct dst_entry *dst;
78 struct inet_sock *inet = inet_sk(sk);
79 struct ipv6_pinfo *np = inet6_sk(sk: sk);
80 struct flowi6 fl6;
81 int err = 0;
82
83 if (inet6_test_bit(SNDFLOW, sk) &&
84 (np->flow_label & IPV6_FLOWLABEL_MASK)) {
85 flowlabel = fl6_sock_lookup(sk, label: np->flow_label);
86 if (IS_ERR(ptr: flowlabel))
87 return -EINVAL;
88 }
89 ip6_datagram_flow_key_init(fl6: &fl6, sk);
90
91 rcu_read_lock();
92 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
93 final_p = fl6_update_dst(fl6: &fl6, opt, orig: &final);
94 rcu_read_unlock();
95
96 dst = ip6_dst_lookup_flow(net: sock_net(sk), sk, fl6: &fl6, final_dst: final_p);
97 if (IS_ERR(ptr: dst)) {
98 err = PTR_ERR(ptr: dst);
99 goto out;
100 }
101
102 if (fix_sk_saddr) {
103 if (ipv6_addr_any(a: &np->saddr))
104 np->saddr = fl6.saddr;
105
106 if (ipv6_addr_any(a: &sk->sk_v6_rcv_saddr)) {
107 sk->sk_v6_rcv_saddr = fl6.saddr;
108 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
109 if (sk->sk_prot->rehash)
110 sk->sk_prot->rehash(sk);
111 }
112 }
113
114 ip6_sk_dst_store_flow(sk, dst, fl6: &fl6);
115
116out:
117 fl6_sock_release(fl: flowlabel);
118 return err;
119}
120
121void ip6_datagram_release_cb(struct sock *sk)
122{
123 struct dst_entry *dst;
124
125 if (ipv6_addr_v4mapped(a: &sk->sk_v6_daddr))
126 return;
127
128 rcu_read_lock();
129 dst = __sk_dst_get(sk);
130 if (!dst || !READ_ONCE(dst->obsolete) ||
131 dst->ops->check(dst, inet6_sk(sk: sk)->dst_cookie)) {
132 rcu_read_unlock();
133 return;
134 }
135 rcu_read_unlock();
136
137 ip6_datagram_dst_update(sk, fix_sk_saddr: false);
138}
139EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
140
141int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
142 int addr_len)
143{
144 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
145 struct inet_sock *inet = inet_sk(sk);
146 struct ipv6_pinfo *np = inet6_sk(sk: sk);
147 struct in6_addr *daddr, old_daddr;
148 __be32 fl6_flowlabel = 0;
149 __be32 old_fl6_flowlabel;
150 __be16 old_dport;
151 int addr_type;
152 int err;
153
154 if (usin->sin6_family == AF_INET) {
155 if (ipv6_only_sock(sk))
156 return -EAFNOSUPPORT;
157 err = __ip4_datagram_connect(sk, uaddr, addr_len);
158 goto ipv4_connected;
159 }
160
161 if (addr_len < SIN6_LEN_RFC2133)
162 return -EINVAL;
163
164 if (usin->sin6_family != AF_INET6)
165 return -EAFNOSUPPORT;
166
167 if (inet6_test_bit(SNDFLOW, sk))
168 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
169
170 if (ipv6_addr_any(a: &usin->sin6_addr)) {
171 /*
172 * connect to self
173 */
174 if (ipv6_addr_v4mapped(a: &sk->sk_v6_rcv_saddr))
175 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
176 v4mapped: &usin->sin6_addr);
177 else
178 usin->sin6_addr = in6addr_loopback;
179 }
180
181 addr_type = ipv6_addr_type(addr: &usin->sin6_addr);
182
183 daddr = &usin->sin6_addr;
184
185 if (addr_type & IPV6_ADDR_MAPPED) {
186 struct sockaddr_in sin;
187
188 if (ipv6_only_sock(sk)) {
189 err = -ENETUNREACH;
190 goto out;
191 }
192 sin.sin_family = AF_INET;
193 sin.sin_addr.s_addr = daddr->s6_addr32[3];
194 sin.sin_port = usin->sin6_port;
195
196 err = __ip4_datagram_connect(sk,
197 uaddr: (struct sockaddr *) &sin,
198 addr_len: sizeof(sin));
199
200ipv4_connected:
201 if (err)
202 goto out;
203
204 ipv6_addr_set_v4mapped(addr: inet->inet_daddr, v4mapped: &sk->sk_v6_daddr);
205
206 if (ipv6_addr_any(a: &np->saddr) ||
207 ipv6_mapped_addr_any(a: &np->saddr))
208 ipv6_addr_set_v4mapped(addr: inet->inet_saddr, v4mapped: &np->saddr);
209
210 if (ipv6_addr_any(a: &sk->sk_v6_rcv_saddr) ||
211 ipv6_mapped_addr_any(a: &sk->sk_v6_rcv_saddr)) {
212 ipv6_addr_set_v4mapped(addr: inet->inet_rcv_saddr,
213 v4mapped: &sk->sk_v6_rcv_saddr);
214 if (sk->sk_prot->rehash)
215 sk->sk_prot->rehash(sk);
216 }
217
218 goto out;
219 }
220
221 if (__ipv6_addr_needs_scope_id(type: addr_type)) {
222 if (addr_len >= sizeof(struct sockaddr_in6) &&
223 usin->sin6_scope_id) {
224 if (!sk_dev_equal_l3scope(sk, dif: usin->sin6_scope_id)) {
225 err = -EINVAL;
226 goto out;
227 }
228 WRITE_ONCE(sk->sk_bound_dev_if, usin->sin6_scope_id);
229 }
230
231 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
232 WRITE_ONCE(sk->sk_bound_dev_if, READ_ONCE(np->mcast_oif));
233
234 /* Connect to link-local address requires an interface */
235 if (!sk->sk_bound_dev_if) {
236 err = -EINVAL;
237 goto out;
238 }
239 }
240
241 /* save the current peer information before updating it */
242 old_daddr = sk->sk_v6_daddr;
243 old_fl6_flowlabel = np->flow_label;
244 old_dport = inet->inet_dport;
245
246 sk->sk_v6_daddr = *daddr;
247 np->flow_label = fl6_flowlabel;
248 inet->inet_dport = usin->sin6_port;
249
250 /*
251 * Check for a route to destination an obtain the
252 * destination cache for it.
253 */
254
255 err = ip6_datagram_dst_update(sk, fix_sk_saddr: true);
256 if (err) {
257 /* Restore the socket peer info, to keep it consistent with
258 * the old socket state
259 */
260 sk->sk_v6_daddr = old_daddr;
261 np->flow_label = old_fl6_flowlabel;
262 inet->inet_dport = old_dport;
263 goto out;
264 }
265
266 reuseport_has_conns_set(sk);
267 sk->sk_state = TCP_ESTABLISHED;
268 sk_set_txhash(sk);
269out:
270 return err;
271}
272EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
273
274int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
275{
276 int res;
277
278 lock_sock(sk);
279 res = __ip6_datagram_connect(sk, uaddr, addr_len);
280 release_sock(sk);
281 return res;
282}
283EXPORT_SYMBOL_GPL(ip6_datagram_connect);
284
285int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
286 int addr_len)
287{
288 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
289 if (sin6->sin6_family != AF_INET6)
290 return -EAFNOSUPPORT;
291 return ip6_datagram_connect(sk, uaddr, addr_len);
292}
293EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
294
295static void ipv6_icmp_error_rfc4884(const struct sk_buff *skb,
296 struct sock_ee_data_rfc4884 *out)
297{
298 switch (icmp6_hdr(skb)->icmp6_type) {
299 case ICMPV6_TIME_EXCEED:
300 case ICMPV6_DEST_UNREACH:
301 ip_icmp_error_rfc4884(skb, out, thlen: sizeof(struct icmp6hdr),
302 off: icmp6_hdr(skb)->icmp6_datagram_len * 8);
303 }
304}
305
306void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
307 __be16 port, u32 info, u8 *payload)
308{
309 struct icmp6hdr *icmph = icmp6_hdr(skb);
310 struct sock_exterr_skb *serr;
311
312 if (!inet6_test_bit(RECVERR6, sk))
313 return;
314
315 skb = skb_clone(skb, GFP_ATOMIC);
316 if (!skb)
317 return;
318
319 skb->protocol = htons(ETH_P_IPV6);
320
321 serr = SKB_EXT_ERR(skb);
322 serr->ee.ee_errno = err;
323 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
324 serr->ee.ee_type = icmph->icmp6_type;
325 serr->ee.ee_code = icmph->icmp6_code;
326 serr->ee.ee_pad = 0;
327 serr->ee.ee_info = info;
328 serr->ee.ee_data = 0;
329 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
330 skb_network_header(skb);
331 serr->port = port;
332
333 __skb_pull(skb, len: payload - skb->data);
334
335 if (inet6_test_bit(RECVERR6_RFC4884, sk))
336 ipv6_icmp_error_rfc4884(skb, out: &serr->ee.ee_rfc4884);
337
338 skb_reset_transport_header(skb);
339
340 if (sock_queue_err_skb(sk, skb))
341 kfree_skb(skb);
342}
343EXPORT_SYMBOL_GPL(ipv6_icmp_error);
344
345void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
346{
347 struct sock_exterr_skb *serr;
348 struct ipv6hdr *iph;
349 struct sk_buff *skb;
350
351 if (!inet6_test_bit(RECVERR6, sk))
352 return;
353
354 skb = alloc_skb(size: sizeof(struct ipv6hdr), GFP_ATOMIC);
355 if (!skb)
356 return;
357
358 skb->protocol = htons(ETH_P_IPV6);
359
360 skb_put(skb, len: sizeof(struct ipv6hdr));
361 skb_reset_network_header(skb);
362 iph = ipv6_hdr(skb);
363 iph->daddr = fl6->daddr;
364 ip6_flow_hdr(hdr: iph, tclass: 0, flowlabel: 0);
365
366 serr = SKB_EXT_ERR(skb);
367 serr->ee.ee_errno = err;
368 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
369 serr->ee.ee_type = 0;
370 serr->ee.ee_code = 0;
371 serr->ee.ee_pad = 0;
372 serr->ee.ee_info = info;
373 serr->ee.ee_data = 0;
374 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
375 serr->port = fl6->fl6_dport;
376
377 __skb_pull(skb, len: skb_tail_pointer(skb) - skb->data);
378 skb_reset_transport_header(skb);
379
380 if (sock_queue_err_skb(sk, skb))
381 kfree_skb(skb);
382}
383
384void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
385{
386 struct ipv6_pinfo *np = inet6_sk(sk: sk);
387 struct ipv6hdr *iph;
388 struct sk_buff *skb;
389 struct ip6_mtuinfo *mtu_info;
390
391 if (!np->rxopt.bits.rxpmtu)
392 return;
393
394 skb = alloc_skb(size: sizeof(struct ipv6hdr), GFP_ATOMIC);
395 if (!skb)
396 return;
397
398 skb_put(skb, len: sizeof(struct ipv6hdr));
399 skb_reset_network_header(skb);
400 iph = ipv6_hdr(skb);
401 iph->daddr = fl6->daddr;
402
403 mtu_info = IP6CBMTU(skb);
404
405 mtu_info->ip6m_mtu = mtu;
406 mtu_info->ip6m_addr.sin6_family = AF_INET6;
407 mtu_info->ip6m_addr.sin6_port = 0;
408 mtu_info->ip6m_addr.sin6_flowinfo = 0;
409 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
410 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
411
412 __skb_pull(skb, len: skb_tail_pointer(skb) - skb->data);
413 skb_reset_transport_header(skb);
414
415 skb = xchg(&np->rxpmtu, skb);
416 kfree_skb(skb);
417}
418
419/* For some errors we have valid addr_offset even with zero payload and
420 * zero port. Also, addr_offset should be supported if port is set.
421 */
422static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
423{
424 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
425 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
426 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
427}
428
429/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
430 *
431 * At one point, excluding local errors was a quick test to identify icmp/icmp6
432 * errors. This is no longer true, but the test remained, so the v6 stack,
433 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
434 */
435static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
436 struct sock_exterr_skb *serr)
437{
438 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
439 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
440 return true;
441
442 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
443 return false;
444
445 if (!IP6CB(skb)->iif)
446 return false;
447
448 return true;
449}
450
451/*
452 * Handle MSG_ERRQUEUE
453 */
454int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
455{
456 struct ipv6_pinfo *np = inet6_sk(sk: sk);
457 struct sock_exterr_skb *serr;
458 struct sk_buff *skb;
459 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
460 struct {
461 struct sock_extended_err ee;
462 struct sockaddr_in6 offender;
463 } errhdr;
464 int err;
465 int copied;
466
467 err = -EAGAIN;
468 skb = sock_dequeue_err_skb(sk);
469 if (!skb)
470 goto out;
471
472 copied = skb->len;
473 if (copied > len) {
474 msg->msg_flags |= MSG_TRUNC;
475 copied = len;
476 }
477 err = skb_copy_datagram_msg(from: skb, offset: 0, msg, size: copied);
478 if (unlikely(err)) {
479 kfree_skb(skb);
480 return err;
481 }
482 sock_recv_timestamp(msg, sk, skb);
483
484 serr = SKB_EXT_ERR(skb);
485
486 if (sin && ipv6_datagram_support_addr(serr)) {
487 const unsigned char *nh = skb_network_header(skb);
488 sin->sin6_family = AF_INET6;
489 sin->sin6_flowinfo = 0;
490 sin->sin6_port = serr->port;
491 if (skb->protocol == htons(ETH_P_IPV6)) {
492 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
493 struct ipv6hdr, daddr);
494 sin->sin6_addr = ip6h->daddr;
495 if (inet6_test_bit(SNDFLOW, sk))
496 sin->sin6_flowinfo = ip6_flowinfo(hdr: ip6h);
497 sin->sin6_scope_id =
498 ipv6_iface_scope_id(addr: &sin->sin6_addr,
499 IP6CB(skb)->iif);
500 } else {
501 ipv6_addr_set_v4mapped(addr: *(__be32 *)(nh + serr->addr_offset),
502 v4mapped: &sin->sin6_addr);
503 sin->sin6_scope_id = 0;
504 }
505 *addr_len = sizeof(*sin);
506 }
507
508 memcpy(to: &errhdr.ee, from: &serr->ee, len: sizeof(struct sock_extended_err));
509 sin = &errhdr.offender;
510 memset(s: sin, c: 0, n: sizeof(*sin));
511
512 if (ip6_datagram_support_cmsg(skb, serr)) {
513 sin->sin6_family = AF_INET6;
514 if (np->rxopt.all)
515 ip6_datagram_recv_common_ctl(sk, msg, skb);
516 if (skb->protocol == htons(ETH_P_IPV6)) {
517 sin->sin6_addr = ipv6_hdr(skb)->saddr;
518 if (np->rxopt.all)
519 ip6_datagram_recv_specific_ctl(sk, msg, skb);
520 sin->sin6_scope_id =
521 ipv6_iface_scope_id(addr: &sin->sin6_addr,
522 IP6CB(skb)->iif);
523 } else {
524 ipv6_addr_set_v4mapped(addr: ip_hdr(skb)->saddr,
525 v4mapped: &sin->sin6_addr);
526 if (inet_cmsg_flags(inet_sk(sk)))
527 ip_cmsg_recv(msg, skb);
528 }
529 }
530
531 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, len: sizeof(errhdr), data: &errhdr);
532
533 /* Now we could try to dump offended packet options */
534
535 msg->msg_flags |= MSG_ERRQUEUE;
536 err = copied;
537
538 consume_skb(skb);
539out:
540 return err;
541}
542EXPORT_SYMBOL_GPL(ipv6_recv_error);
543
544/*
545 * Handle IPV6_RECVPATHMTU
546 */
547int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
548 int *addr_len)
549{
550 struct ipv6_pinfo *np = inet6_sk(sk: sk);
551 struct sk_buff *skb;
552 struct ip6_mtuinfo mtu_info;
553 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
554 int err;
555 int copied;
556
557 err = -EAGAIN;
558 skb = xchg(&np->rxpmtu, NULL);
559 if (!skb)
560 goto out;
561
562 copied = skb->len;
563 if (copied > len) {
564 msg->msg_flags |= MSG_TRUNC;
565 copied = len;
566 }
567 err = skb_copy_datagram_msg(from: skb, offset: 0, msg, size: copied);
568 if (err)
569 goto out_free_skb;
570
571 sock_recv_timestamp(msg, sk, skb);
572
573 memcpy(to: &mtu_info, IP6CBMTU(skb), len: sizeof(mtu_info));
574
575 if (sin) {
576 sin->sin6_family = AF_INET6;
577 sin->sin6_flowinfo = 0;
578 sin->sin6_port = 0;
579 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
580 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
581 *addr_len = sizeof(*sin);
582 }
583
584 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, len: sizeof(mtu_info), data: &mtu_info);
585
586 err = copied;
587
588out_free_skb:
589 kfree_skb(skb);
590out:
591 return err;
592}
593
594
595void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
596 struct sk_buff *skb)
597{
598 struct ipv6_pinfo *np = inet6_sk(sk: sk);
599 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
600
601 if (np->rxopt.bits.rxinfo) {
602 struct in6_pktinfo src_info;
603
604 if (is_ipv6) {
605 src_info.ipi6_ifindex = IP6CB(skb)->iif;
606 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
607 } else {
608 src_info.ipi6_ifindex =
609 PKTINFO_SKB_CB(skb)->ipi_ifindex;
610 ipv6_addr_set_v4mapped(addr: ip_hdr(skb)->daddr,
611 v4mapped: &src_info.ipi6_addr);
612 }
613
614 if (src_info.ipi6_ifindex >= 0)
615 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
616 len: sizeof(src_info), data: &src_info);
617 }
618}
619
620void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
621 struct sk_buff *skb)
622{
623 struct ipv6_pinfo *np = inet6_sk(sk: sk);
624 struct inet6_skb_parm *opt = IP6CB(skb);
625 unsigned char *nh = skb_network_header(skb);
626
627 if (np->rxopt.bits.rxhlim) {
628 int hlim = ipv6_hdr(skb)->hop_limit;
629 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, len: sizeof(hlim), data: &hlim);
630 }
631
632 if (np->rxopt.bits.rxtclass) {
633 int tclass = ipv6_get_dsfield(ipv6h: ipv6_hdr(skb));
634 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, len: sizeof(tclass), data: &tclass);
635 }
636
637 if (np->rxopt.bits.rxflow) {
638 __be32 flowinfo = ip6_flowinfo(hdr: (struct ipv6hdr *)nh);
639 if (flowinfo)
640 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, len: sizeof(flowinfo), data: &flowinfo);
641 }
642
643 /* HbH is allowed only once */
644 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
645 u8 *ptr = nh + sizeof(struct ipv6hdr);
646 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, len: (ptr[1]+1)<<3, data: ptr);
647 }
648
649 if (opt->lastopt &&
650 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
651 /*
652 * Silly enough, but we need to reparse in order to
653 * report extension headers (except for HbH)
654 * in order.
655 *
656 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
657 * (and WILL NOT be) defined because
658 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
659 */
660 unsigned int off = sizeof(struct ipv6hdr);
661 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
662
663 while (off <= opt->lastopt) {
664 unsigned int len;
665 u8 *ptr = nh + off;
666
667 switch (nexthdr) {
668 case IPPROTO_DSTOPTS:
669 nexthdr = ptr[0];
670 len = (ptr[1] + 1) << 3;
671 if (np->rxopt.bits.dstopts)
672 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, data: ptr);
673 break;
674 case IPPROTO_ROUTING:
675 nexthdr = ptr[0];
676 len = (ptr[1] + 1) << 3;
677 if (np->rxopt.bits.srcrt)
678 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, data: ptr);
679 break;
680 case IPPROTO_AH:
681 nexthdr = ptr[0];
682 len = (ptr[1] + 2) << 2;
683 break;
684 default:
685 nexthdr = ptr[0];
686 len = (ptr[1] + 1) << 3;
687 break;
688 }
689
690 off += len;
691 }
692 }
693
694 /* socket options in old style */
695 if (np->rxopt.bits.rxoinfo) {
696 struct in6_pktinfo src_info;
697
698 src_info.ipi6_ifindex = opt->iif;
699 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
700 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, len: sizeof(src_info), data: &src_info);
701 }
702 if (np->rxopt.bits.rxohlim) {
703 int hlim = ipv6_hdr(skb)->hop_limit;
704 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, len: sizeof(hlim), data: &hlim);
705 }
706 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
707 u8 *ptr = nh + sizeof(struct ipv6hdr);
708 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, len: (ptr[1]+1)<<3, data: ptr);
709 }
710 if (np->rxopt.bits.odstopts && opt->dst0) {
711 u8 *ptr = nh + opt->dst0;
712 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, len: (ptr[1]+1)<<3, data: ptr);
713 }
714 if (np->rxopt.bits.osrcrt && opt->srcrt) {
715 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
716 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, len: (rthdr->hdrlen+1) << 3, data: rthdr);
717 }
718 if (np->rxopt.bits.odstopts && opt->dst1) {
719 u8 *ptr = nh + opt->dst1;
720 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, len: (ptr[1]+1)<<3, data: ptr);
721 }
722 if (np->rxopt.bits.rxorigdstaddr) {
723 struct sockaddr_in6 sin6;
724 __be16 _ports[2], *ports;
725
726 ports = skb_header_pointer(skb, offset: skb_transport_offset(skb),
727 len: sizeof(_ports), buffer: &_ports);
728 if (ports) {
729 /* All current transport protocols have the port numbers in the
730 * first four bytes of the transport header and this function is
731 * written with this assumption in mind.
732 */
733 sin6.sin6_family = AF_INET6;
734 sin6.sin6_addr = ipv6_hdr(skb)->daddr;
735 sin6.sin6_port = ports[1];
736 sin6.sin6_flowinfo = 0;
737 sin6.sin6_scope_id =
738 ipv6_iface_scope_id(addr: &ipv6_hdr(skb)->daddr,
739 iface: opt->iif);
740
741 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, len: sizeof(sin6), data: &sin6);
742 }
743 }
744 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
745 int val = opt->frag_max_size;
746
747 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, len: sizeof(val), data: &val);
748 }
749}
750
751void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
752 struct sk_buff *skb)
753{
754 ip6_datagram_recv_common_ctl(sk, msg, skb);
755 ip6_datagram_recv_specific_ctl(sk, msg, skb);
756}
757EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
758
759int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
760 struct msghdr *msg, struct flowi6 *fl6,
761 struct ipcm6_cookie *ipc6)
762{
763 struct in6_pktinfo *src_info;
764 struct cmsghdr *cmsg;
765 struct ipv6_rt_hdr *rthdr;
766 struct ipv6_opt_hdr *hdr;
767 struct ipv6_txoptions *opt = ipc6->opt;
768 int len;
769 int err = 0;
770
771 for_each_cmsghdr(cmsg, msg) {
772 int addr_type;
773
774 if (!CMSG_OK(msg, cmsg)) {
775 err = -EINVAL;
776 goto exit_f;
777 }
778
779 if (cmsg->cmsg_level == SOL_SOCKET) {
780 err = __sock_cmsg_send(sk, cmsg, sockc: &ipc6->sockc);
781 if (err)
782 return err;
783 continue;
784 }
785
786 if (cmsg->cmsg_level != SOL_IPV6)
787 continue;
788
789 switch (cmsg->cmsg_type) {
790 case IPV6_PKTINFO:
791 case IPV6_2292PKTINFO:
792 {
793 struct net_device *dev = NULL;
794 int src_idx;
795
796 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
797 err = -EINVAL;
798 goto exit_f;
799 }
800
801 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
802 src_idx = src_info->ipi6_ifindex;
803
804 if (src_idx) {
805 if (fl6->flowi6_oif &&
806 src_idx != fl6->flowi6_oif &&
807 (READ_ONCE(sk->sk_bound_dev_if) != fl6->flowi6_oif ||
808 !sk_dev_equal_l3scope(sk, dif: src_idx)))
809 return -EINVAL;
810 fl6->flowi6_oif = src_idx;
811 }
812
813 addr_type = __ipv6_addr_type(addr: &src_info->ipi6_addr);
814
815 rcu_read_lock();
816 if (fl6->flowi6_oif) {
817 dev = dev_get_by_index_rcu(net, ifindex: fl6->flowi6_oif);
818 if (!dev) {
819 rcu_read_unlock();
820 return -ENODEV;
821 }
822 } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
823 rcu_read_unlock();
824 return -EINVAL;
825 }
826
827 if (addr_type != IPV6_ADDR_ANY) {
828 int strict = __ipv6_addr_src_scope(type: addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
829 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) &&
830 !ipv6_chk_addr_and_flags(net, addr: &src_info->ipi6_addr,
831 dev, skip_dev_check: !strict, strict: 0,
832 IFA_F_TENTATIVE) &&
833 !ipv6_chk_acast_addr_src(net, dev,
834 addr: &src_info->ipi6_addr))
835 err = -EINVAL;
836 else
837 fl6->saddr = src_info->ipi6_addr;
838 }
839
840 rcu_read_unlock();
841
842 if (err)
843 goto exit_f;
844
845 break;
846 }
847
848 case IPV6_FLOWINFO:
849 if (cmsg->cmsg_len < CMSG_LEN(4)) {
850 err = -EINVAL;
851 goto exit_f;
852 }
853
854 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
855 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
856 err = -EINVAL;
857 goto exit_f;
858 }
859 }
860 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
861 break;
862
863 case IPV6_2292HOPOPTS:
864 case IPV6_HOPOPTS:
865 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
866 err = -EINVAL;
867 goto exit_f;
868 }
869
870 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
871 len = ((hdr->hdrlen + 1) << 3);
872 if (cmsg->cmsg_len < CMSG_LEN(len)) {
873 err = -EINVAL;
874 goto exit_f;
875 }
876 if (!ns_capable(ns: net->user_ns, CAP_NET_RAW)) {
877 err = -EPERM;
878 goto exit_f;
879 }
880 opt->opt_nflen += len;
881 opt->hopopt = hdr;
882 break;
883
884 case IPV6_2292DSTOPTS:
885 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
886 err = -EINVAL;
887 goto exit_f;
888 }
889
890 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
891 len = ((hdr->hdrlen + 1) << 3);
892 if (cmsg->cmsg_len < CMSG_LEN(len)) {
893 err = -EINVAL;
894 goto exit_f;
895 }
896 if (!ns_capable(ns: net->user_ns, CAP_NET_RAW)) {
897 err = -EPERM;
898 goto exit_f;
899 }
900 if (opt->dst1opt) {
901 err = -EINVAL;
902 goto exit_f;
903 }
904 opt->opt_flen += len;
905 opt->dst1opt = hdr;
906 break;
907
908 case IPV6_DSTOPTS:
909 case IPV6_RTHDRDSTOPTS:
910 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
911 err = -EINVAL;
912 goto exit_f;
913 }
914
915 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
916 len = ((hdr->hdrlen + 1) << 3);
917 if (cmsg->cmsg_len < CMSG_LEN(len)) {
918 err = -EINVAL;
919 goto exit_f;
920 }
921 if (!ns_capable(ns: net->user_ns, CAP_NET_RAW)) {
922 err = -EPERM;
923 goto exit_f;
924 }
925 if (cmsg->cmsg_type == IPV6_DSTOPTS) {
926 opt->opt_flen += len;
927 opt->dst1opt = hdr;
928 } else {
929 opt->opt_nflen += len;
930 opt->dst0opt = hdr;
931 }
932 break;
933
934 case IPV6_2292RTHDR:
935 case IPV6_RTHDR:
936 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
937 err = -EINVAL;
938 goto exit_f;
939 }
940
941 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
942
943 switch (rthdr->type) {
944#if IS_ENABLED(CONFIG_IPV6_MIP6)
945 case IPV6_SRCRT_TYPE_2:
946 if (rthdr->hdrlen != 2 ||
947 rthdr->segments_left != 1) {
948 err = -EINVAL;
949 goto exit_f;
950 }
951 break;
952#endif
953 default:
954 err = -EINVAL;
955 goto exit_f;
956 }
957
958 len = ((rthdr->hdrlen + 1) << 3);
959
960 if (cmsg->cmsg_len < CMSG_LEN(len)) {
961 err = -EINVAL;
962 goto exit_f;
963 }
964
965 /* segments left must also match */
966 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
967 err = -EINVAL;
968 goto exit_f;
969 }
970
971 opt->opt_nflen += len;
972 opt->srcrt = rthdr;
973
974 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
975 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
976
977 opt->opt_nflen += dsthdrlen;
978 opt->dst0opt = opt->dst1opt;
979 opt->dst1opt = NULL;
980 opt->opt_flen -= dsthdrlen;
981 }
982
983 break;
984
985 case IPV6_2292HOPLIMIT:
986 case IPV6_HOPLIMIT:
987 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
988 err = -EINVAL;
989 goto exit_f;
990 }
991
992 ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
993 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
994 err = -EINVAL;
995 goto exit_f;
996 }
997
998 break;
999
1000 case IPV6_TCLASS:
1001 {
1002 int tc;
1003
1004 err = -EINVAL;
1005 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1006 goto exit_f;
1007
1008 tc = *(int *)CMSG_DATA(cmsg);
1009 if (tc < -1 || tc > 0xff)
1010 goto exit_f;
1011
1012 err = 0;
1013 ipc6->tclass = tc;
1014
1015 break;
1016 }
1017
1018 case IPV6_DONTFRAG:
1019 {
1020 int df;
1021
1022 err = -EINVAL;
1023 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
1024 goto exit_f;
1025
1026 df = *(int *)CMSG_DATA(cmsg);
1027 if (df < 0 || df > 1)
1028 goto exit_f;
1029
1030 err = 0;
1031 ipc6->dontfrag = df;
1032
1033 break;
1034 }
1035 default:
1036 net_dbg_ratelimited("invalid cmsg type: %d\n",
1037 cmsg->cmsg_type);
1038 err = -EINVAL;
1039 goto exit_f;
1040 }
1041 }
1042
1043exit_f:
1044 return err;
1045}
1046EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1047
1048void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1049 __u16 srcp, __u16 destp, int rqueue, int bucket)
1050{
1051 const struct in6_addr *dest, *src;
1052
1053 dest = &sp->sk_v6_daddr;
1054 src = &sp->sk_v6_rcv_saddr;
1055 seq_printf(m: seq,
1056 fmt: "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1057 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
1058 bucket,
1059 src->s6_addr32[0], src->s6_addr32[1],
1060 src->s6_addr32[2], src->s6_addr32[3], srcp,
1061 dest->s6_addr32[0], dest->s6_addr32[1],
1062 dest->s6_addr32[2], dest->s6_addr32[3], destp,
1063 sp->sk_state,
1064 sk_wmem_alloc_get(sk: sp),
1065 rqueue,
1066 0, 0L, 0,
1067 from_kuid_munged(to: seq_user_ns(seq), kuid: sk_uid(sk: sp)),
1068 0,
1069 sock_i_ino(sk: sp),
1070 refcount_read(r: &sp->sk_refcnt), sp,
1071 sk_drops_read(sk: sp));
1072}
1073