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 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
29 #include <linux/ipv6.h>
30 #endif
31 
32 #define MAX_INET_PROTOS	256		/* Must be a power of 2		*/
33 
34 
35 /* This is used to register protocols. */
36 struct net_protocol {
37 	int			(*handler)(struct sk_buff *skb);
38 	void			(*err_handler)(struct sk_buff *skb, u32 info);
39 	int			(*gso_send_check)(struct sk_buff *skb);
40 	struct sk_buff	       *(*gso_segment)(struct sk_buff *skb,
41 					       u32 features);
42 	struct sk_buff	      **(*gro_receive)(struct sk_buff **head,
43 					       struct sk_buff *skb);
44 	int			(*gro_complete)(struct sk_buff *skb);
45 	unsigned int		no_policy:1,
46 				netns_ok:1;
47 };
48 
49 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
50 struct inet6_protocol {
51 	int	(*handler)(struct sk_buff *skb);
52 
53 	void	(*err_handler)(struct sk_buff *skb,
54 			       struct inet6_skb_parm *opt,
55 			       u8 type, u8 code, int offset,
56 			       __be32 info);
57 
58 	int	(*gso_send_check)(struct sk_buff *skb);
59 	struct sk_buff *(*gso_segment)(struct sk_buff *skb,
60 				       u32 features);
61 	struct sk_buff **(*gro_receive)(struct sk_buff **head,
62 					struct sk_buff *skb);
63 	int	(*gro_complete)(struct sk_buff *skb);
64 
65 	unsigned int	flags;	/* INET6_PROTO_xxx */
66 };
67 
68 #define INET6_PROTO_NOPOLICY	0x1
69 #define INET6_PROTO_FINAL	0x2
70 /* This should be set for any extension header which is compatible with GSO. */
71 #define INET6_PROTO_GSO_EXTHDR	0x4
72 #endif
73 
74 /* This is used to register socket interfaces for IP protocols.  */
75 struct inet_protosw {
76 	struct list_head list;
77 
78         /* These two fields form the lookup key.  */
79 	unsigned short	 type;	   /* This is the 2nd argument to socket(2). */
80 	unsigned short	 protocol; /* This is the L4 protocol number.  */
81 
82 	struct proto	 *prot;
83 	const struct proto_ops *ops;
84 
85 	char             no_check;   /* checksum on rcv/xmit/none? */
86 	unsigned char	 flags;      /* See INET_PROTOSW_* below.  */
87 };
88 #define INET_PROTOSW_REUSE 0x01	     /* Are ports automatically reusable? */
89 #define INET_PROTOSW_PERMANENT 0x02  /* Permanent protocols are unremovable. */
90 #define INET_PROTOSW_ICSK      0x04  /* Is this an inet_connection_sock? */
91 
92 extern const struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS];
93 
94 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
95 extern const struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS];
96 #endif
97 
98 extern int	inet_add_protocol(const struct net_protocol *prot, unsigned char num);
99 extern int	inet_del_protocol(const struct net_protocol *prot, unsigned char num);
100 extern void	inet_register_protosw(struct inet_protosw *p);
101 extern void	inet_unregister_protosw(struct inet_protosw *p);
102 
103 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
104 extern int	inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num);
105 extern int	inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num);
106 extern int	inet6_register_protosw(struct inet_protosw *p);
107 extern void	inet6_unregister_protosw(struct inet_protosw *p);
108 #endif
109 
110 #endif	/* _PROTOCOL_H */
111