1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the protocol dispatcher. 8 * 9 * Version: @(#)protocol.h 1.0.2 05/07/93 10 * 11 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * 13 * Changes: 14 * Alan Cox : Added a name field and a frag handler 15 * field for later. 16 * Alan Cox : Cleaned up, and sorted types. 17 * Pedro Roque : inet6 protocols 18 */ 19 20 #ifndef _PROTOCOL_H 21 #define _PROTOCOL_H 22 23 #include <linux/in6.h> 24 #include <linux/skbuff.h> 25 #if IS_ENABLED(CONFIG_IPV6) 26 #include <linux/ipv6.h> 27 #endif 28 #include <linux/netdevice.h> 29 30 /* This is one larger than the largest protocol value that can be 31 * found in an ipv4 or ipv6 header. Since in both cases the protocol 32 * value is presented in a __u8, this is defined to be 256. 33 */ 34 #define MAX_INET_PROTOS 256 35 36 /* This is used to register protocols. */ 37 struct net_protocol { 38 int (*handler)(struct sk_buff *skb); 39 40 /* This returns an error if we weren't able to handle the error. */ 41 int (*err_handler)(struct sk_buff *skb, u32 info); 42 43 unsigned int no_policy:1, 44 netns_ok:1, 45 /* does the protocol do more stringent 46 * icmp tag validation than simple 47 * socket lookup? 48 */ 49 icmp_strict_tag_validation:1; 50 }; 51 52 #if IS_ENABLED(CONFIG_IPV6) 53 struct inet6_protocol { 54 int (*handler)(struct sk_buff *skb); 55 56 /* This returns an error if we weren't able to handle the error. */ 57 int (*err_handler)(struct sk_buff *skb, 58 struct inet6_skb_parm *opt, 59 u8 type, u8 code, int offset, 60 __be32 info); 61 62 unsigned int flags; /* INET6_PROTO_xxx */ 63 }; 64 65 #define INET6_PROTO_NOPOLICY 0x1 66 #define INET6_PROTO_FINAL 0x2 67 #endif 68 69 struct net_offload { 70 struct offload_callbacks callbacks; 71 unsigned int flags; /* Flags used by IPv6 for now */ 72 }; 73 /* This should be set for any extension header which is compatible with GSO. */ 74 #define INET6_PROTO_GSO_EXTHDR 0x1 75 76 /* This is used to register socket interfaces for IP protocols. */ 77 struct inet_protosw { 78 struct list_head list; 79 80 /* These two fields form the lookup key. */ 81 unsigned short type; /* This is the 2nd argument to socket(2). */ 82 unsigned short protocol; /* This is the L4 protocol number. */ 83 84 struct proto *prot; 85 const struct proto_ops *ops; 86 87 unsigned char flags; /* See INET_PROTOSW_* below. */ 88 }; 89 #define INET_PROTOSW_REUSE 0x01 /* Are ports automatically reusable? */ 90 #define INET_PROTOSW_PERMANENT 0x02 /* Permanent protocols are unremovable. */ 91 #define INET_PROTOSW_ICSK 0x04 /* Is this an inet_connection_sock? */ 92 93 extern struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS]; 94 extern const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS]; 95 extern const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS]; 96 97 #if IS_ENABLED(CONFIG_IPV6) 98 extern struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS]; 99 #endif 100 101 int inet_add_protocol(const struct net_protocol *prot, unsigned char num); 102 int inet_del_protocol(const struct net_protocol *prot, unsigned char num); 103 int inet_add_offload(const struct net_offload *prot, unsigned char num); 104 int inet_del_offload(const struct net_offload *prot, unsigned char num); 105 void inet_register_protosw(struct inet_protosw *p); 106 void inet_unregister_protosw(struct inet_protosw *p); 107 108 #if IS_ENABLED(CONFIG_IPV6) 109 int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num); 110 int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num); 111 int inet6_register_protosw(struct inet_protosw *p); 112 void inet6_unregister_protosw(struct inet_protosw *p); 113 #endif 114 int inet6_add_offload(const struct net_offload *prot, unsigned char num); 115 int inet6_del_offload(const struct net_offload *prot, unsigned char num); 116 117 #endif /* _PROTOCOL_H */ 118