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 (*early_demux)(struct sk_buff *skb); 39 int (*early_demux_handler)(struct sk_buff *skb); 40 int (*handler)(struct sk_buff *skb); 41 42 /* This returns an error if we weren't able to handle the error. */ 43 int (*err_handler)(struct sk_buff *skb, u32 info); 44 45 unsigned int no_policy:1, 46 /* does the protocol do more stringent 47 * icmp tag validation than simple 48 * socket lookup? 49 */ 50 icmp_strict_tag_validation:1; 51 }; 52 53 #if IS_ENABLED(CONFIG_IPV6) 54 struct inet6_protocol { 55 void (*early_demux)(struct sk_buff *skb); 56 void (*early_demux_handler)(struct sk_buff *skb); 57 int (*handler)(struct sk_buff *skb); 58 59 /* This returns an error if we weren't able to handle the error. */ 60 int (*err_handler)(struct sk_buff *skb, 61 struct inet6_skb_parm *opt, 62 u8 type, u8 code, int offset, 63 __be32 info); 64 65 unsigned int flags; /* INET6_PROTO_xxx */ 66 }; 67 68 #define INET6_PROTO_NOPOLICY 0x1 69 #define INET6_PROTO_FINAL 0x2 70 #endif 71 72 struct 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. */ 80 struct 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 96 extern struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS]; 97 extern const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS]; 98 extern const struct net_offload __rcu *inet6_offloads[MAX_INET_PROTOS]; 99 100 #if IS_ENABLED(CONFIG_IPV6) 101 extern struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS]; 102 #endif 103 104 int inet_add_protocol(const struct net_protocol *prot, unsigned char num); 105 int inet_del_protocol(const struct net_protocol *prot, unsigned char num); 106 int inet_add_offload(const struct net_offload *prot, unsigned char num); 107 int inet_del_offload(const struct net_offload *prot, unsigned char num); 108 void inet_register_protosw(struct inet_protosw *p); 109 void inet_unregister_protosw(struct inet_protosw *p); 110 111 #if IS_ENABLED(CONFIG_IPV6) 112 int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char num); 113 int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char num); 114 int inet6_register_protosw(struct inet_protosw *p); 115 void inet6_unregister_protosw(struct inet_protosw *p); 116 #endif 117 int inet6_add_offload(const struct net_offload *prot, unsigned char num); 118 int inet6_del_offload(const struct net_offload *prot, unsigned char num); 119 120 #endif /* _PROTOCOL_H */ 121