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	void			(*early_demux)(struct sk_buff *skb);
43	int			(*handler)(struct sk_buff *skb);
44	void			(*err_handler)(struct sk_buff *skb, u32 info);
45	unsigned int		no_policy:1,
46				netns_ok:1,
47				/* does the protocol do more stringent
48				 * icmp tag validation than simple
49				 * socket lookup?
50				 */
51				icmp_strict_tag_validation:1;
52};
53
54#if IS_ENABLED(CONFIG_IPV6)
55struct inet6_protocol {
56	void	(*early_demux)(struct sk_buff *skb);
57
58	int	(*handler)(struct sk_buff *skb);
59
60	void	(*err_handler)(struct sk_buff *skb,
61			       struct inet6_skb_parm *opt,
62			       u8 type, u8 code, int offset,
63			       __be32 info);
64	unsigned int	flags;	/* INET6_PROTO_xxx */
65};
66
67#define INET6_PROTO_NOPOLICY	0x1
68#define INET6_PROTO_FINAL	0x2
69#endif
70
71struct net_offload {
72	struct offload_callbacks callbacks;
73	unsigned int		 flags;	/* Flags used by IPv6 for now */
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 const 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 const 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
110int  udp_add_offload(struct udp_offload *prot);
111void udp_del_offload(struct udp_offload *prot);
112
113#if IS_ENABLED(CONFIG_IPV6)
114int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num);
115int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num);
116int inet6_register_protosw(struct inet_protosw *p);
117void inet6_unregister_protosw(struct inet_protosw *p);
118#endif
119int inet6_add_offload(const struct net_offload *prot, unsigned char num);
120int inet6_del_offload(const struct net_offload *prot, unsigned char num);
121
122#endif	/* _PROTOCOL_H */
123