route.h 8.5 KB

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  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. #include <net/dst.h>
  27. #include <net/inetpeer.h>
  28. #include <net/flow.h>
  29. #include <net/inet_sock.h>
  30. #include <linux/in_route.h>
  31. #include <linux/rtnetlink.h>
  32. #include <linux/route.h>
  33. #include <linux/ip.h>
  34. #include <linux/cache.h>
  35. #include <linux/security.h>
  36. #ifndef __KERNEL__
  37. #warning This file is not supposed to be used outside of kernel.
  38. #endif
  39. #define RTO_ONLINK 0x01
  40. #define RTO_CONN 0
  41. /* RTO_CONN is not used (being alias for 0), but preserved not to break
  42. * some modules referring to it. */
  43. #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
  44. struct fib_nh;
  45. struct inet_peer;
  46. struct fib_info;
  47. struct rtable {
  48. struct dst_entry dst;
  49. /* Lookup key. */
  50. __be32 rt_key_dst;
  51. __be32 rt_key_src;
  52. int rt_genid;
  53. unsigned rt_flags;
  54. __u16 rt_type;
  55. __u8 rt_tos;
  56. __be32 rt_dst; /* Path destination */
  57. __be32 rt_src; /* Path source */
  58. int rt_route_iif;
  59. int rt_iif;
  60. int rt_oif;
  61. __u32 rt_mark;
  62. /* Info on neighbour */
  63. __be32 rt_gateway;
  64. /* Miscellaneous cached information */
  65. __be32 rt_spec_dst; /* RFC1122 specific destination */
  66. u32 rt_peer_genid;
  67. struct inet_peer *peer; /* long-living peer info */
  68. struct fib_info *fi; /* for client ref to shared metrics */
  69. };
  70. static inline bool rt_is_input_route(struct rtable *rt)
  71. {
  72. return rt->rt_route_iif != 0;
  73. }
  74. static inline bool rt_is_output_route(struct rtable *rt)
  75. {
  76. return rt->rt_route_iif == 0;
  77. }
  78. struct ip_rt_acct {
  79. __u32 o_bytes;
  80. __u32 o_packets;
  81. __u32 i_bytes;
  82. __u32 i_packets;
  83. };
  84. struct rt_cache_stat {
  85. unsigned int in_hit;
  86. unsigned int in_slow_tot;
  87. unsigned int in_slow_mc;
  88. unsigned int in_no_route;
  89. unsigned int in_brd;
  90. unsigned int in_martian_dst;
  91. unsigned int in_martian_src;
  92. unsigned int out_hit;
  93. unsigned int out_slow_tot;
  94. unsigned int out_slow_mc;
  95. unsigned int gc_total;
  96. unsigned int gc_ignored;
  97. unsigned int gc_goal_miss;
  98. unsigned int gc_dst_overflow;
  99. unsigned int in_hlist_search;
  100. unsigned int out_hlist_search;
  101. };
  102. extern struct ip_rt_acct __percpu *ip_rt_acct;
  103. struct in_device;
  104. extern int ip_rt_init(void);
  105. extern void ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
  106. __be32 src, struct net_device *dev);
  107. extern void rt_cache_flush(struct net *net, int how);
  108. extern void rt_cache_flush_batch(struct net *net);
  109. extern struct rtable *__ip_route_output_key(struct net *, const struct flowi4 *flp);
  110. extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
  111. struct sock *sk);
  112. extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);
  113. static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp)
  114. {
  115. return ip_route_output_flow(net, flp, NULL);
  116. }
  117. static inline struct rtable *ip_route_output(struct net *net, __be32 daddr,
  118. __be32 saddr, u8 tos, int oif)
  119. {
  120. struct flowi4 fl4 = {
  121. .flowi4_oif = oif,
  122. .daddr = daddr,
  123. .saddr = saddr,
  124. .flowi4_tos = tos,
  125. };
  126. return ip_route_output_key(net, &fl4);
  127. }
  128. static inline struct rtable *ip_route_output_ports(struct net *net, struct sock *sk,
  129. __be32 daddr, __be32 saddr,
  130. __be16 dport, __be16 sport,
  131. __u8 proto, __u8 tos, int oif)
  132. {
  133. struct flowi4 fl4 = {
  134. .flowi4_oif = oif,
  135. .flowi4_flags = sk ? inet_sk_flowi_flags(sk) : 0,
  136. .flowi4_mark = sk ? sk->sk_mark : 0,
  137. .daddr = daddr,
  138. .saddr = saddr,
  139. .flowi4_tos = tos,
  140. .flowi4_proto = proto,
  141. .fl4_dport = dport,
  142. .fl4_sport = sport,
  143. };
  144. if (sk)
  145. security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
  146. return ip_route_output_flow(net, &fl4, sk);
  147. }
  148. static inline struct rtable *ip_route_output_gre(struct net *net,
  149. __be32 daddr, __be32 saddr,
  150. __be32 gre_key, __u8 tos, int oif)
  151. {
  152. struct flowi4 fl4 = {
  153. .flowi4_oif = oif,
  154. .daddr = daddr,
  155. .saddr = saddr,
  156. .flowi4_tos = tos,
  157. .flowi4_proto = IPPROTO_GRE,
  158. .fl4_gre_key = gre_key,
  159. };
  160. return ip_route_output_key(net, &fl4);
  161. }
  162. extern int ip_route_input_common(struct sk_buff *skb, __be32 dst, __be32 src,
  163. u8 tos, struct net_device *devin, bool noref);
  164. static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src,
  165. u8 tos, struct net_device *devin)
  166. {
  167. return ip_route_input_common(skb, dst, src, tos, devin, false);
  168. }
  169. static inline int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src,
  170. u8 tos, struct net_device *devin)
  171. {
  172. return ip_route_input_common(skb, dst, src, tos, devin, true);
  173. }
  174. extern unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu, struct net_device *dev);
  175. extern void ip_rt_send_redirect(struct sk_buff *skb);
  176. extern unsigned inet_addr_type(struct net *net, __be32 addr);
  177. extern unsigned inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr);
  178. extern void ip_rt_multicast_event(struct in_device *);
  179. extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg);
  180. extern void ip_rt_get_source(u8 *src, struct rtable *rt);
  181. extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb);
  182. struct in_ifaddr;
  183. extern void fib_add_ifaddr(struct in_ifaddr *);
  184. extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *);
  185. static inline void ip_rt_put(struct rtable * rt)
  186. {
  187. if (rt)
  188. dst_release(&rt->dst);
  189. }
  190. #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3)
  191. extern const __u8 ip_tos2prio[16];
  192. static inline char rt_tos2priority(u8 tos)
  193. {
  194. return ip_tos2prio[IPTOS_TOS(tos)>>1];
  195. }
  196. static inline struct rtable *ip_route_connect(__be32 dst, __be32 src, u32 tos,
  197. int oif, u8 protocol,
  198. __be16 sport, __be16 dport,
  199. struct sock *sk, bool can_sleep)
  200. {
  201. struct flowi4 fl4 = {
  202. .flowi4_oif = oif,
  203. .flowi4_mark = sk->sk_mark,
  204. .daddr = dst,
  205. .saddr = src,
  206. .flowi4_tos = tos,
  207. .flowi4_proto = protocol,
  208. .fl4_sport = sport,
  209. .fl4_dport = dport,
  210. };
  211. struct net *net = sock_net(sk);
  212. struct rtable *rt;
  213. if (inet_sk(sk)->transparent)
  214. fl4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
  215. if (protocol == IPPROTO_TCP)
  216. fl4.flowi4_flags |= FLOWI_FLAG_PRECOW_METRICS;
  217. if (can_sleep)
  218. fl4.flowi4_flags |= FLOWI_FLAG_CAN_SLEEP;
  219. if (!dst || !src) {
  220. rt = __ip_route_output_key(net, &fl4);
  221. if (IS_ERR(rt))
  222. return rt;
  223. fl4.daddr = rt->rt_dst;
  224. fl4.saddr = rt->rt_src;
  225. ip_rt_put(rt);
  226. }
  227. security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
  228. return ip_route_output_flow(net, &fl4, sk);
  229. }
  230. static inline struct rtable *ip_route_newports(struct rtable *rt,
  231. u8 protocol, __be16 orig_sport,
  232. __be16 orig_dport, __be16 sport,
  233. __be16 dport, struct sock *sk)
  234. {
  235. if (sport != orig_sport || dport != orig_dport) {
  236. struct flowi4 fl4 = {
  237. .flowi4_oif = rt->rt_oif,
  238. .flowi4_mark = rt->rt_mark,
  239. .daddr = rt->rt_dst,
  240. .saddr = rt->rt_src,
  241. .flowi4_tos = rt->rt_tos,
  242. .flowi4_proto = protocol,
  243. .fl4_sport = sport,
  244. .fl4_dport = dport
  245. };
  246. if (inet_sk(sk)->transparent)
  247. fl4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
  248. if (protocol == IPPROTO_TCP)
  249. fl4.flowi4_flags |= FLOWI_FLAG_PRECOW_METRICS;
  250. ip_rt_put(rt);
  251. security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
  252. return ip_route_output_flow(sock_net(sk), &fl4, sk);
  253. }
  254. return rt;
  255. }
  256. extern void rt_bind_peer(struct rtable *rt, int create);
  257. static inline struct inet_peer *rt_get_peer(struct rtable *rt)
  258. {
  259. if (rt->peer)
  260. return rt->peer;
  261. rt_bind_peer(rt, 0);
  262. return rt->peer;
  263. }
  264. static inline int inet_iif(const struct sk_buff *skb)
  265. {
  266. return skb_rtable(skb)->rt_iif;
  267. }
  268. extern int sysctl_ip_default_ttl;
  269. static inline int ip4_dst_hoplimit(const struct dst_entry *dst)
  270. {
  271. int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
  272. if (hoplimit == 0)
  273. hoplimit = sysctl_ip_default_ttl;
  274. return hoplimit;
  275. }
  276. #endif /* _ROUTE_H */