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 #if IS_ENABLED(CONFIG_IPV6)
  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                                                netdev_features_t 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 IS_ENABLED(CONFIG_IPV6)
  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                                        netdev_features_t 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 IS_ENABLED(CONFIG_IPV6)
  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 IS_ENABLED(CONFIG_IPV6)
 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 */