1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the protocol dispatcher.
7 *
8 * Version: @(#)protocol.h 1.0.2 05/07/93
9 *
10 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 *
17 * Changes:
18 * Alan Cox : Added a name field and a frag handler
19 * field for later.
20 * Alan Cox : Cleaned up, and sorted types.
21 * Pedro Roque : inet6 protocols
22 */
23
24#ifndef _PROTOCOL_H
25#define _PROTOCOL_H
26
27#include <linux/in6.h>
28#include <linux/skbuff.h>
29#if IS_ENABLED(CONFIG_IPV6)
30#include <linux/ipv6.h>
31#endif
32#include <linux/netdevice.h>
33
34/* This is one larger than the largest protocol value that can be
35 * found in an ipv4 or ipv6 header. Since in both cases the protocol
36 * value is presented in a __u8, this is defined to be 256.
37 */
38#define MAX_INET_PROTOS 256
39
40/* This is used to register protocols. */
41struct net_protocol {
42 int (*early_demux)(struct sk_buff *skb);
43 int (*early_demux_handler)(struct sk_buff *skb);
44 int (*handler)(struct sk_buff *skb);
45
46 /* This returns an error if we weren't able to handle the error. */
47 int (*err_handler)(struct sk_buff *skb, u32 info);
48
49 unsigned int no_policy:1,
50 netns_ok:1,
51 /* does the protocol do more stringent
52 * icmp tag validation than simple
53 * socket lookup?
54 */
55 icmp_strict_tag_validation:1;
56};
57
58#if IS_ENABLED(CONFIG_IPV6)
59struct inet6_protocol {
60 void (*early_demux)(struct sk_buff *skb);
61 void (*early_demux_handler)(struct sk_buff *skb);
62 int (*handler)(struct sk_buff *skb);
63
64 /* This returns an error if we weren't able to handle the error. */
65 int (*err_handler)(struct sk_buff *skb,
66 struct inet6_skb_parm *opt,
67 u8 type, u8 code, int offset,
68 __be32 info);
69
70 unsigned int flags; /* INET6_PROTO_xxx */
71};
72
73#define INET6_PROTO_NOPOLICY 0x1
74#define INET6_PROTO_FINAL 0x2
75#endif
76
77struct net_offload {
78 struct offload_callbacks callbacks;
79 unsigned int flags; /* Flags used by IPv6 for now */
80};
81/* This should be set for any extension header which is compatible with GSO. */
82#define INET6_PROTO_GSO_EXTHDR 0x1
83
84/* This is used to register socket interfaces for IP protocols. */
85struct inet_protosw {
86 struct list_head list;
87
88 /* These two fields form the lookup key. */
89 unsigned short type; /* This is the 2nd argument to socket(2). */
90 unsigned short protocol; /* This is the L4 protocol number. */
91
92 struct proto *prot;
93 const struct proto_ops *ops;
94
95 unsigned char flags; /* See INET_PROTOSW_* below. */
96};
97#define INET_PROTOSW_REUSE 0x01 /* Are ports automatically reusable? */
98#define INET_PROTOSW_PERMANENT 0x02 /* Permanent protocols are unremovable. */
99#define INET_PROTOSW_ICSK 0x04 /* Is this an inet_connection_sock? */
100
101extern struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS];
102extern const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS];
103extern const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS];
104
105#if IS_ENABLED(CONFIG_IPV6)
106extern struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS];
107#endif
108
109int inet_add_protocol(const struct net_protocol *prot, unsigned char num);
110int inet_del_protocol(const struct net_protocol *prot, unsigned char num);
111int inet_add_offload(const struct net_offload *prot, unsigned char num);
112int inet_del_offload(const struct net_offload *prot, unsigned char num);
113void inet_register_protosw(struct inet_protosw *p);
114void inet_unregister_protosw(struct inet_protosw *p);
115
116#if IS_ENABLED(CONFIG_IPV6)
117int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num);
118int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num);
119int inet6_register_protosw(struct inet_protosw *p);
120void inet6_unregister_protosw(struct inet_protosw *p);
121#endif
122int inet6_add_offload(const struct net_offload *prot, unsigned char num);
123int inet6_del_offload(const struct net_offload *prot, unsigned char num);
124
125#endif /* _PROTOCOL_H */
126