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.
6 * Definitions for the IP router.
8 * Version: @(#)route.h 1.0.4 05/27/93
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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
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.
28 #include <net/inetpeer.h>
30 #include <net/inet_sock.h>
31 #include <linux/in_route.h>
32 #include <linux/rtnetlink.h>
33 #include <linux/route.h>
35 #include <linux/cache.h>
36 #include <linux/security.h>
38 #define RTO_ONLINK 0x01
41 /* RTO_CONN is not used (being alias for 0), but preserved not to break
42 * some modules referring to it. */
44 #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
61 __be32 rt_dst; /* Path destination */
62 __be32 rt_src; /* Path source */
68 /* Info on neighbour */
71 /* Miscellaneous cached information */
72 __be32 rt_spec_dst; /* RFC1122 specific destination */
74 struct inet_peer *peer; /* long-living peer info */
75 struct fib_info *fi; /* for client ref to shared metrics */
78 static inline bool rt_is_input_route(struct rtable *rt)
80 return rt->rt_route_iif != 0;
83 static inline bool rt_is_output_route(struct rtable *rt)
85 return rt->rt_route_iif == 0;
95 struct rt_cache_stat {
97 unsigned int in_slow_tot;
98 unsigned int in_slow_mc;
99 unsigned int in_no_route;
101 unsigned int in_martian_dst;
102 unsigned int in_martian_src;
103 unsigned int out_hit;
104 unsigned int out_slow_tot;
105 unsigned int out_slow_mc;
106 unsigned int gc_total;
107 unsigned int gc_ignored;
108 unsigned int gc_goal_miss;
109 unsigned int gc_dst_overflow;
110 unsigned int in_hlist_search;
111 unsigned int out_hlist_search;
114 extern struct ip_rt_acct __percpu *ip_rt_acct;
117 extern int ip_rt_init(void);
118 extern void ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
119 __be32 src, struct net_device *dev);
120 extern void rt_cache_flush(struct net *net, int how);
121 extern void rt_cache_flush_batch(struct net *net);
122 extern struct rtable *__ip_route_output_key(struct net *, const struct flowi4 *flp);
123 extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
125 extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);
127 static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp)
129 return ip_route_output_flow(net, flp, NULL);
132 static inline struct rtable *ip_route_output(struct net *net, __be32 daddr,
133 __be32 saddr, u8 tos, int oif)
135 struct flowi4 fl4 = {
141 return ip_route_output_key(net, &fl4);
144 static inline struct rtable *ip_route_output_ports(struct net *net, struct sock *sk,
145 __be32 daddr, __be32 saddr,
146 __be16 dport, __be16 sport,
147 __u8 proto, __u8 tos, int oif)
151 flowi4_init_output(&fl4, oif, sk ? sk->sk_mark : 0, tos,
152 RT_SCOPE_UNIVERSE, proto,
153 sk ? inet_sk_flowi_flags(sk) : 0,
154 daddr, saddr, dport, sport);
156 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
157 return ip_route_output_flow(net, &fl4, sk);
160 static inline struct rtable *ip_route_output_gre(struct net *net,
161 __be32 daddr, __be32 saddr,
162 __be32 gre_key, __u8 tos, int oif)
164 struct flowi4 fl4 = {
169 .flowi4_proto = IPPROTO_GRE,
170 .fl4_gre_key = gre_key,
172 return ip_route_output_key(net, &fl4);
175 extern int ip_route_input_common(struct sk_buff *skb, __be32 dst, __be32 src,
176 u8 tos, struct net_device *devin, bool noref);
178 static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src,
179 u8 tos, struct net_device *devin)
181 return ip_route_input_common(skb, dst, src, tos, devin, false);
184 static inline int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src,
185 u8 tos, struct net_device *devin)
187 return ip_route_input_common(skb, dst, src, tos, devin, true);
190 extern unsigned short ip_rt_frag_needed(struct net *net, const struct iphdr *iph,
191 unsigned short new_mtu, struct net_device *dev);
192 extern void ip_rt_send_redirect(struct sk_buff *skb);
194 extern unsigned inet_addr_type(struct net *net, __be32 addr);
195 extern unsigned inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr);
196 extern void ip_rt_multicast_event(struct in_device *);
197 extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg);
198 extern void ip_rt_get_source(u8 *src, struct rtable *rt);
199 extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb);
202 extern void fib_add_ifaddr(struct in_ifaddr *);
203 extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *);
205 static inline void ip_rt_put(struct rtable * rt)
208 dst_release(&rt->dst);
211 #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3)
213 extern const __u8 ip_tos2prio[16];
215 static inline char rt_tos2priority(u8 tos)
217 return ip_tos2prio[IPTOS_TOS(tos)>>1];
220 static inline struct rtable *ip_route_connect(__be32 dst, __be32 src, u32 tos,
221 int oif, u8 protocol,
222 __be16 sport, __be16 dport,
223 struct sock *sk, bool can_sleep)
225 struct net *net = sock_net(sk);
231 if (inet_sk(sk)->transparent)
232 flow_flags |= FLOWI_FLAG_ANYSRC;
233 if (protocol == IPPROTO_TCP)
234 flow_flags |= FLOWI_FLAG_PRECOW_METRICS;
236 flow_flags |= FLOWI_FLAG_CAN_SLEEP;
238 flowi4_init_output(&fl4, oif, sk->sk_mark, tos, RT_SCOPE_UNIVERSE,
239 protocol, flow_flags, dst, src, dport, sport);
242 rt = __ip_route_output_key(net, &fl4);
245 fl4.daddr = rt->rt_dst;
246 fl4.saddr = rt->rt_src;
249 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
250 return ip_route_output_flow(net, &fl4, sk);
253 static inline struct rtable *ip_route_newports(struct rtable *rt,
254 u8 protocol, __be16 orig_sport,
255 __be16 orig_dport, __be16 sport,
256 __be16 dport, struct sock *sk)
258 if (sport != orig_sport || dport != orig_dport) {
263 if (inet_sk(sk)->transparent)
264 flow_flags |= FLOWI_FLAG_ANYSRC;
265 if (protocol == IPPROTO_TCP)
266 flow_flags |= FLOWI_FLAG_PRECOW_METRICS;
267 flowi4_init_output(&fl4, rt->rt_oif, rt->rt_mark, rt->rt_tos,
268 RT_SCOPE_UNIVERSE, protocol, flow_flags,
269 rt->rt_dst, rt->rt_src, dport, sport);
271 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
272 return ip_route_output_flow(sock_net(sk), &fl4, sk);
277 extern void rt_bind_peer(struct rtable *rt, int create);
279 static inline struct inet_peer *rt_get_peer(struct rtable *rt)
288 static inline int inet_iif(const struct sk_buff *skb)
290 return skb_rtable(skb)->rt_iif;
293 extern int sysctl_ip_default_ttl;
295 static inline int ip4_dst_hoplimit(const struct dst_entry *dst)
297 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
300 hoplimit = sysctl_ip_default_ttl;
304 #endif /* _ROUTE_H */