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 union { 54 struct dst_entry dst; 55 } u; 56 57 /* Cache lookup keys */ 58 struct flowi fl; 59 60 struct in_device *idev; 61 62 int rt_genid; 63 unsigned rt_flags; 64 __u16 rt_type; 65 66 __be32 rt_dst; /* Path destination */ 67 __be32 rt_src; /* Path source */ 68 int rt_iif; 69 70 /* Info on neighbour */ 71 __be32 rt_gateway; 72 73 /* Miscellaneous cached information */ 74 __be32 rt_spec_dst; /* RFC1122 specific destination */ 75 struct inet_peer *peer; /* long-living peer info */ 76 }; 77 78 struct ip_rt_acct { 79 __u32 o_bytes; 80 __u32 o_packets; 81 __u32 i_bytes; 82 __u32 i_packets; 83 }; 84 85 struct rt_cache_stat { 86 unsigned int in_hit; 87 unsigned int in_slow_tot; 88 unsigned int in_slow_mc; 89 unsigned int in_no_route; 90 unsigned int in_brd; 91 unsigned int in_martian_dst; 92 unsigned int in_martian_src; 93 unsigned int out_hit; 94 unsigned int out_slow_tot; 95 unsigned int out_slow_mc; 96 unsigned int gc_total; 97 unsigned int gc_ignored; 98 unsigned int gc_goal_miss; 99 unsigned int gc_dst_overflow; 100 unsigned int in_hlist_search; 101 unsigned int out_hlist_search; 102 }; 103 104 extern struct ip_rt_acct __percpu *ip_rt_acct; 105 106 struct in_device; 107 extern int ip_rt_init(void); 108 extern void ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw, 109 __be32 src, struct net_device *dev); 110 extern void rt_cache_flush(struct net *net, int how); 111 extern void rt_cache_flush_batch(void); 112 extern int __ip_route_output_key(struct net *, struct rtable **, const struct flowi *flp); 113 extern int ip_route_output_key(struct net *, struct rtable **, struct flowi *flp); 114 extern int ip_route_output_flow(struct net *, struct rtable **rp, struct flowi *flp, struct sock *sk, int flags); 115 116 extern int ip_route_input_common(struct sk_buff *skb, __be32 dst, __be32 src, 117 u8 tos, struct net_device *devin, bool noref); 118 119 static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, 120 u8 tos, struct net_device *devin) 121 { 122 return ip_route_input_common(skb, dst, src, tos, devin, false); 123 } 124 125 static inline int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src, 126 u8 tos, struct net_device *devin) 127 { 128 return ip_route_input_common(skb, dst, src, tos, devin, true); 129 } 130 131 extern unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu, struct net_device *dev); 132 extern void ip_rt_send_redirect(struct sk_buff *skb); 133 134 extern unsigned inet_addr_type(struct net *net, __be32 addr); 135 extern unsigned inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr); 136 extern void ip_rt_multicast_event(struct in_device *); 137 extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg); 138 extern void ip_rt_get_source(u8 *src, struct rtable *rt); 139 extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb); 140 141 struct in_ifaddr; 142 extern void fib_add_ifaddr(struct in_ifaddr *); 143 144 static inline void ip_rt_put(struct rtable * rt) 145 { 146 if (rt) 147 dst_release(&rt->u.dst); 148 } 149 150 #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3) 151 152 extern const __u8 ip_tos2prio[16]; 153 154 static inline char rt_tos2priority(u8 tos) 155 { 156 return ip_tos2prio[IPTOS_TOS(tos)>>1]; 157 } 158 159 static inline int ip_route_connect(struct rtable **rp, __be32 dst, 160 __be32 src, u32 tos, int oif, u8 protocol, 161 __be16 sport, __be16 dport, struct sock *sk, 162 int flags) 163 { 164 struct flowi fl = { .oif = oif, 165 .mark = sk->sk_mark, 166 .nl_u = { .ip4_u = { .daddr = dst, 167 .saddr = src, 168 .tos = tos } }, 169 .proto = protocol, 170 .uli_u = { .ports = 171 { .sport = sport, 172 .dport = dport } } }; 173 174 int err; 175 struct net *net = sock_net(sk); 176 177 if (inet_sk(sk)->transparent) 178 fl.flags |= FLOWI_FLAG_ANYSRC; 179 180 if (!dst || !src) { 181 err = __ip_route_output_key(net, rp, &fl); 182 if (err) 183 return err; 184 fl.fl4_dst = (*rp)->rt_dst; 185 fl.fl4_src = (*rp)->rt_src; 186 ip_rt_put(*rp); 187 *rp = NULL; 188 } 189 security_sk_classify_flow(sk, &fl); 190 return ip_route_output_flow(net, rp, &fl, sk, flags); 191 } 192 193 static inline int ip_route_newports(struct rtable **rp, u8 protocol, 194 __be16 sport, __be16 dport, struct sock *sk) 195 { 196 if (sport != (*rp)->fl.fl_ip_sport || 197 dport != (*rp)->fl.fl_ip_dport) { 198 struct flowi fl; 199 200 memcpy(&fl, &(*rp)->fl, sizeof(fl)); 201 fl.fl_ip_sport = sport; 202 fl.fl_ip_dport = dport; 203 fl.proto = protocol; 204 ip_rt_put(*rp); 205 *rp = NULL; 206 security_sk_classify_flow(sk, &fl); 207 return ip_route_output_flow(sock_net(sk), rp, &fl, sk, 0); 208 } 209 return 0; 210 } 211 212 extern void rt_bind_peer(struct rtable *rt, int create); 213 214 static inline struct inet_peer *rt_get_peer(struct rtable *rt) 215 { 216 if (rt->peer) 217 return rt->peer; 218 219 rt_bind_peer(rt, 0); 220 return rt->peer; 221 } 222 223 static inline int inet_iif(const struct sk_buff *skb) 224 { 225 return skb_rtable(skb)->rt_iif; 226 } 227 228 #endif /* _ROUTE_H */ 229