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 IP router. 7 * 8 * Version: @(#)route.h 1.0.4 05/27/93 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Fixes: 13 * Alan Cox : Reformatted. Added ip_rt_local() 14 * Alan Cox : Support for TCP parameters. 15 * Alexey Kuznetsov: Major changes for new routing code. 16 * Mike McLagan : Routing by source 17 * Robert Olsson : Added rt_cache statistics 18 * 19 * This program is free software; you can redistribute it and/or 20 * modify it under the terms of the GNU General Public License 21 * as published by the Free Software Foundation; either version 22 * 2 of the License, or (at your option) any later version. 23 */ 24 #ifndef _ROUTE_H 25 #define _ROUTE_H 26 27 #include <net/dst.h> 28 #include <net/inetpeer.h> 29 #include <net/flow.h> 30 #include <net/inet_sock.h> 31 #include <linux/in_route.h> 32 #include <linux/rtnetlink.h> 33 #include <linux/route.h> 34 #include <linux/ip.h> 35 #include <linux/cache.h> 36 #include <linux/security.h> 37 38 #ifndef __KERNEL__ 39 #warning This file is not supposed to be used outside of kernel. 40 #endif 41 42 #define RTO_ONLINK 0x01 43 44 #define RTO_CONN 0 45 /* RTO_CONN is not used (being alias for 0), but preserved not to break 46 * some modules referring to it. */ 47 48 #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE)) 49 50 struct fib_nh; 51 struct inet_peer; 52 struct rtable 53 { 54 union 55 { 56 struct dst_entry dst; 57 } u; 58 59 /* Cache lookup keys */ 60 struct flowi fl; 61 62 struct in_device *idev; 63 64 int rt_genid; 65 unsigned rt_flags; 66 __u16 rt_type; 67 68 __be32 rt_dst; /* Path destination */ 69 __be32 rt_src; /* Path source */ 70 int rt_iif; 71 72 /* Info on neighbour */ 73 __be32 rt_gateway; 74 75 /* Miscellaneous cached information */ 76 __be32 rt_spec_dst; /* RFC1122 specific destination */ 77 struct inet_peer *peer; /* long-living peer info */ 78 }; 79 80 struct ip_rt_acct 81 { 82 __u32 o_bytes; 83 __u32 o_packets; 84 __u32 i_bytes; 85 __u32 i_packets; 86 }; 87 88 struct rt_cache_stat 89 { 90 unsigned int in_hit; 91 unsigned int in_slow_tot; 92 unsigned int in_slow_mc; 93 unsigned int in_no_route; 94 unsigned int in_brd; 95 unsigned int in_martian_dst; 96 unsigned int in_martian_src; 97 unsigned int out_hit; 98 unsigned int out_slow_tot; 99 unsigned int out_slow_mc; 100 unsigned int gc_total; 101 unsigned int gc_ignored; 102 unsigned int gc_goal_miss; 103 unsigned int gc_dst_overflow; 104 unsigned int in_hlist_search; 105 unsigned int out_hlist_search; 106 }; 107 108 extern struct ip_rt_acct *ip_rt_acct; 109 110 struct in_device; 111 extern int ip_rt_init(void); 112 extern void ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw, 113 __be32 src, struct net_device *dev); 114 extern void rt_cache_flush(struct net *net, int how); 115 extern int __ip_route_output_key(struct net *, struct rtable **, const struct flowi *flp); 116 extern int ip_route_output_key(struct net *, struct rtable **, struct flowi *flp); 117 extern int ip_route_output_flow(struct net *, struct rtable **rp, struct flowi *flp, struct sock *sk, int flags); 118 extern int ip_route_input(struct sk_buff*, __be32 dst, __be32 src, u8 tos, struct net_device *devin); 119 extern unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu, struct net_device *dev); 120 extern void ip_rt_send_redirect(struct sk_buff *skb); 121 122 extern unsigned inet_addr_type(struct net *net, __be32 addr); 123 extern unsigned inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr); 124 extern void ip_rt_multicast_event(struct in_device *); 125 extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg); 126 extern void ip_rt_get_source(u8 *src, struct rtable *rt); 127 extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb); 128 129 struct in_ifaddr; 130 extern void fib_add_ifaddr(struct in_ifaddr *); 131 132 static inline void ip_rt_put(struct rtable * rt) 133 { 134 if (rt) 135 dst_release(&rt->u.dst); 136 } 137 138 #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3) 139 140 extern const __u8 ip_tos2prio[16]; 141 142 static inline char rt_tos2priority(u8 tos) 143 { 144 return ip_tos2prio[IPTOS_TOS(tos)>>1]; 145 } 146 147 static inline int ip_route_connect(struct rtable **rp, __be32 dst, 148 __be32 src, u32 tos, int oif, u8 protocol, 149 __be16 sport, __be16 dport, struct sock *sk, 150 int flags) 151 { 152 struct flowi fl = { .oif = oif, 153 .mark = sk->sk_mark, 154 .nl_u = { .ip4_u = { .daddr = dst, 155 .saddr = src, 156 .tos = tos } }, 157 .proto = protocol, 158 .uli_u = { .ports = 159 { .sport = sport, 160 .dport = dport } } }; 161 162 int err; 163 struct net *net = sock_net(sk); 164 165 if (inet_sk(sk)->transparent) 166 fl.flags |= FLOWI_FLAG_ANYSRC; 167 168 if (!dst || !src) { 169 err = __ip_route_output_key(net, rp, &fl); 170 if (err) 171 return err; 172 fl.fl4_dst = (*rp)->rt_dst; 173 fl.fl4_src = (*rp)->rt_src; 174 ip_rt_put(*rp); 175 *rp = NULL; 176 } 177 security_sk_classify_flow(sk, &fl); 178 return ip_route_output_flow(net, rp, &fl, sk, flags); 179 } 180 181 static inline int ip_route_newports(struct rtable **rp, u8 protocol, 182 __be16 sport, __be16 dport, struct sock *sk) 183 { 184 if (sport != (*rp)->fl.fl_ip_sport || 185 dport != (*rp)->fl.fl_ip_dport) { 186 struct flowi fl; 187 188 memcpy(&fl, &(*rp)->fl, sizeof(fl)); 189 fl.fl_ip_sport = sport; 190 fl.fl_ip_dport = dport; 191 fl.proto = protocol; 192 ip_rt_put(*rp); 193 *rp = NULL; 194 security_sk_classify_flow(sk, &fl); 195 return ip_route_output_flow(sock_net(sk), rp, &fl, sk, 0); 196 } 197 return 0; 198 } 199 200 extern void rt_bind_peer(struct rtable *rt, int create); 201 202 static inline struct inet_peer *rt_get_peer(struct rtable *rt) 203 { 204 if (rt->peer) 205 return rt->peer; 206 207 rt_bind_peer(rt, 0); 208 return rt->peer; 209 } 210 211 static inline int inet_iif(const struct sk_buff *skb) 212 { 213 return skb_rtable(skb)->rt_iif; 214 } 215 216 #endif /* _ROUTE_H */ 217