1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the protocol dispatcher.
8 *
9 * Version: @(#)protocol.h 1.0.2 05/07/93
10 *
11 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *
13 * Changes:
14 * Alan Cox : Added a name field and a frag handler
15 * field for later.
16 * Alan Cox : Cleaned up, and sorted types.
17 * Pedro Roque : inet6 protocols
18 */
19
20#ifndef _PROTOCOL_H
21#define _PROTOCOL_H
22
23#include <linux/in6.h>
24#include <linux/skbuff.h>
25#if IS_ENABLED(CONFIG_IPV6)
26#include <linux/ipv6.h>
27#endif
28#include <linux/netdevice.h>
29
30/* This is one larger than the largest protocol value that can be
31 * found in an ipv4 or ipv6 header. Since in both cases the protocol
32 * value is presented in a __u8, this is defined to be 256.
33 */
34#define MAX_INET_PROTOS 256
35
36/* This is used to register protocols. */
37struct net_protocol {
38 int (*handler)(struct sk_buff *skb);
39
40 /* This returns an error if we weren't able to handle the error. */
41 int (*err_handler)(struct sk_buff *skb, u32 info);
42
43 unsigned int no_policy:1,
44 /* does the protocol do more stringent
45 * icmp tag validation than simple
46 * socket lookup?
47 */
48 icmp_strict_tag_validation:1;
49 u32 secret;
50};
51
52#if IS_ENABLED(CONFIG_IPV6)
53struct inet6_protocol {
54 int (*handler)(struct sk_buff *skb);
55
56 /* This returns an error if we weren't able to handle the error. */
57 int (*err_handler)(struct sk_buff *skb,
58 struct inet6_skb_parm *opt,
59 u8 type, u8 code, int offset,
60 __be32 info);
61
62 unsigned int flags; /* INET6_PROTO_xxx */
63 u32 secret;
64};
65
66#define INET6_PROTO_NOPOLICY 0x1
67#define INET6_PROTO_FINAL 0x2
68#endif
69
70struct net_offload {
71 struct offload_callbacks callbacks;
72 unsigned int flags; /* Flags used by IPv6 for now */
73 u32 secret;
74};
75/* This should be set for any extension header which is compatible with GSO. */
76#define INET6_PROTO_GSO_EXTHDR 0x1
77
78/* This is used to register socket interfaces for IP protocols. */
79struct inet_protosw {
80 struct list_head list;
81
82 /* These two fields form the lookup key. */
83 unsigned short type; /* This is the 2nd argument to socket(2). */
84 unsigned short protocol; /* This is the L4 protocol number. */
85
86 struct proto *prot;
87 const struct proto_ops *ops;
88
89 unsigned char flags; /* See INET_PROTOSW_* below. */
90};
91#define INET_PROTOSW_REUSE 0x01 /* Are ports automatically reusable? */
92#define INET_PROTOSW_PERMANENT 0x02 /* Permanent protocols are unremovable. */
93#define INET_PROTOSW_ICSK 0x04 /* Is this an inet_connection_sock? */
94
95extern struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS];
96extern const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS];
97extern const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS];
98
99#if IS_ENABLED(CONFIG_IPV6)
100extern struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS];
101#endif
102
103int inet_add_protocol(const struct net_protocol *prot, unsigned char num);
104int inet_del_protocol(const struct net_protocol *prot, unsigned char num);
105int inet_add_offload(const struct net_offload *prot, unsigned char num);
106int inet_del_offload(const struct net_offload *prot, unsigned char num);
107void inet_register_protosw(struct inet_protosw *p);
108void inet_unregister_protosw(struct inet_protosw *p);
109
110#if IS_ENABLED(CONFIG_IPV6)
111int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num);
112int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num);
113int inet6_register_protosw(struct inet_protosw *p);
114void inet6_unregister_protosw(struct inet_protosw *p);
115#endif
116int inet6_add_offload(const struct net_offload *prot, unsigned char num);
117int inet6_del_offload(const struct net_offload *prot, unsigned char num);
118
119#endif /* _PROTOCOL_H */
120