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>
39 #warning This file is not supposed to be used outside of kernel.
42 #define RTO_ONLINK 0x01
45 /* RTO_CONN is not used (being alias for 0), but preserved not to break
46 * some modules referring to it. */
48 #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
56 /* Cache lookup keys */
63 __be32 rt_dst; /* Path destination */
64 __be32 rt_src; /* Path source */
67 /* Info on neighbour */
70 /* Miscellaneous cached information */
71 __be32 rt_spec_dst; /* RFC1122 specific destination */
73 struct inet_peer *peer; /* long-living peer info */
74 struct fib_info *fi; /* for client ref to shared metrics */
77 static inline bool rt_is_input_route(struct rtable *rt)
79 return rt->fl.iif != 0;
82 static inline bool rt_is_output_route(struct rtable *rt)
84 return rt->fl.iif == 0;
94 struct rt_cache_stat {
96 unsigned int in_slow_tot;
97 unsigned int in_slow_mc;
98 unsigned int in_no_route;
100 unsigned int in_martian_dst;
101 unsigned int in_martian_src;
102 unsigned int out_hit;
103 unsigned int out_slow_tot;
104 unsigned int out_slow_mc;
105 unsigned int gc_total;
106 unsigned int gc_ignored;
107 unsigned int gc_goal_miss;
108 unsigned int gc_dst_overflow;
109 unsigned int in_hlist_search;
110 unsigned int out_hlist_search;
113 extern struct ip_rt_acct __percpu *ip_rt_acct;
116 extern int ip_rt_init(void);
117 extern void ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
118 __be32 src, struct net_device *dev);
119 extern void rt_cache_flush(struct net *net, int how);
120 extern void rt_cache_flush_batch(struct net *net);
121 extern int __ip_route_output_key(struct net *, struct rtable **, const struct flowi *flp);
122 extern int ip_route_output_key(struct net *, struct rtable **, struct flowi *flp);
123 extern int ip_route_output_flow(struct net *, struct rtable **rp, struct flowi *flp, struct sock *sk);
124 extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);
126 extern int ip_route_input_common(struct sk_buff *skb, __be32 dst, __be32 src,
127 u8 tos, struct net_device *devin, bool noref);
129 static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src,
130 u8 tos, struct net_device *devin)
132 return ip_route_input_common(skb, dst, src, tos, devin, false);
135 static inline int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src,
136 u8 tos, struct net_device *devin)
138 return ip_route_input_common(skb, dst, src, tos, devin, true);
141 extern unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, unsigned short new_mtu, struct net_device *dev);
142 extern void ip_rt_send_redirect(struct sk_buff *skb);
144 extern unsigned inet_addr_type(struct net *net, __be32 addr);
145 extern unsigned inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr);
146 extern void ip_rt_multicast_event(struct in_device *);
147 extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg);
148 extern void ip_rt_get_source(u8 *src, struct rtable *rt);
149 extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb);
152 extern void fib_add_ifaddr(struct in_ifaddr *);
154 static inline void ip_rt_put(struct rtable * rt)
157 dst_release(&rt->dst);
160 #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3)
162 extern const __u8 ip_tos2prio[16];
164 static inline char rt_tos2priority(u8 tos)
166 return ip_tos2prio[IPTOS_TOS(tos)>>1];
169 static inline int ip_route_connect(struct rtable **rp, __be32 dst,
170 __be32 src, u32 tos, int oif, u8 protocol,
171 __be16 sport, __be16 dport, struct sock *sk,
174 struct flowi fl = { .oif = oif,
180 .fl_ip_sport = sport,
181 .fl_ip_dport = dport };
183 struct net *net = sock_net(sk);
185 if (inet_sk(sk)->transparent)
186 fl.flags |= FLOWI_FLAG_ANYSRC;
187 if (protocol == IPPROTO_TCP)
188 fl.flags |= FLOWI_FLAG_PRECOW_METRICS;
190 fl.flags |= FLOWI_FLAG_CAN_SLEEP;
193 err = __ip_route_output_key(net, rp, &fl);
196 fl.fl4_dst = (*rp)->rt_dst;
197 fl.fl4_src = (*rp)->rt_src;
201 security_sk_classify_flow(sk, &fl);
202 return ip_route_output_flow(net, rp, &fl, sk);
205 static inline int ip_route_newports(struct rtable **rp, u8 protocol,
206 __be16 orig_sport, __be16 orig_dport,
207 __be16 sport, __be16 dport, struct sock *sk)
209 if (sport != orig_sport || dport != orig_dport) {
210 struct flowi fl = { .oif = (*rp)->fl.oif,
211 .mark = (*rp)->fl.mark,
212 .fl4_dst = (*rp)->fl.fl4_dst,
213 .fl4_src = (*rp)->fl.fl4_src,
214 .fl4_tos = (*rp)->fl.fl4_tos,
215 .proto = (*rp)->fl.proto,
216 .fl_ip_sport = sport,
217 .fl_ip_dport = dport };
219 if (inet_sk(sk)->transparent)
220 fl.flags |= FLOWI_FLAG_ANYSRC;
221 if (protocol == IPPROTO_TCP)
222 fl.flags |= FLOWI_FLAG_PRECOW_METRICS;
225 security_sk_classify_flow(sk, &fl);
226 return ip_route_output_flow(sock_net(sk), rp, &fl, sk);
231 extern void rt_bind_peer(struct rtable *rt, int create);
233 static inline struct inet_peer *rt_get_peer(struct rtable *rt)
242 static inline int inet_iif(const struct sk_buff *skb)
244 return skb_rtable(skb)->rt_iif;
247 extern int sysctl_ip_default_ttl;
249 static inline int ip4_dst_hoplimit(const struct dst_entry *dst)
251 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
254 hoplimit = sysctl_ip_default_ttl;
258 #endif /* _ROUTE_H */