LXR linux/include/net/protocol.h

   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        void                    (*err_handler)(struct sk_buff *skb, u32 info);
  46        unsigned int            no_policy:1,
  47                                netns_ok:1,
  48                                /* does the protocol do more stringent
  49                                 * icmp tag validation than simple
  50                                 * socket lookup?
  51                                 */
  52                                icmp_strict_tag_validation:1;
  53};
  54
  55#if IS_ENABLED(CONFIG_IPV6)
  56struct inet6_protocol {
  57        void    (*early_demux)(struct sk_buff *skb);
  58        void    (*early_demux_handler)(struct sk_buff *skb);
  59        int     (*handler)(struct sk_buff *skb);
  60
  61        void    (*err_handler)(struct sk_buff *skb,
  62                               struct inet6_skb_parm *opt,
  63                               u8 type, u8 code, int offset,
  64                               __be32 info);
  65        unsigned int    flags;  /* INET6_PROTO_xxx */
  66};
  67
  68#define INET6_PROTO_NOPOLICY    0x1
  69#define INET6_PROTO_FINAL       0x2
  70#endif
  71
  72struct net_offload {
  73        struct offload_callbacks callbacks;
  74        unsigned int             flags; /* Flags used by IPv6 for now */
  75};
  76/* This should be set for any extension header which is compatible with GSO. */
  77#define INET6_PROTO_GSO_EXTHDR  0x1
  78
  79/* This is used to register socket interfaces for IP protocols.  */
  80struct inet_protosw {
  81        struct list_head list;
  82
  83        /* These two fields form the lookup key.  */
  84        unsigned short   type;     /* This is the 2nd argument to socket(2). */
  85        unsigned short   protocol; /* This is the L4 protocol number.  */
  86
  87        struct proto     *prot;
  88        const struct proto_ops *ops;
  89  
  90        unsigned char    flags;      /* See INET_PROTOSW_* below.  */
  91};
  92#define INET_PROTOSW_REUSE 0x01      /* Are ports automatically reusable? */
  93#define INET_PROTOSW_PERMANENT 0x02  /* Permanent protocols are unremovable. */
  94#define INET_PROTOSW_ICSK      0x04  /* Is this an inet_connection_sock? */
  95
  96extern struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS];
  97extern const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS];
  98extern const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS];
  99
 100#if IS_ENABLED(CONFIG_IPV6)
 101extern struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS];
 102#endif
 103
 104int inet_add_protocol(const struct net_protocol *prot, unsigned char num);
 105int inet_del_protocol(const struct net_protocol *prot, unsigned char num);
 106int inet_add_offload(const struct net_offload *prot, unsigned char num);
 107int inet_del_offload(const struct net_offload *prot, unsigned char num);
 108void inet_register_protosw(struct inet_protosw *p);
 109void inet_unregister_protosw(struct inet_protosw *p);
 110
 111#if IS_ENABLED(CONFIG_IPV6)
 112int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num);
 113int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num);
 114int inet6_register_protosw(struct inet_protosw *p);
 115void inet6_unregister_protosw(struct inet_protosw *p);
 116#endif
 117int inet6_add_offload(const struct net_offload *prot, unsigned char num);
 118int inet6_del_offload(const struct net_offload *prot, unsigned char num);
 119
 120#endif  /* _PROTOCOL_H */
 121