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
40 #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
57 __be32 rt_dst
; /* Path destination */
58 __be32 rt_src
; /* Path source */
64 /* Info on neighbour */
67 /* Miscellaneous cached information */
68 __be32 rt_spec_dst
; /* RFC1122 specific destination */
70 struct inet_peer
*peer
; /* long-living peer info */
71 struct fib_info
*fi
; /* for client ref to shared metrics */
74 static inline bool rt_is_input_route(struct rtable
*rt
)
76 return rt
->rt_route_iif
!= 0;
79 static inline bool rt_is_output_route(struct rtable
*rt
)
81 return rt
->rt_route_iif
== 0;
91 struct rt_cache_stat
{
93 unsigned int in_slow_tot
;
94 unsigned int in_slow_mc
;
95 unsigned int in_no_route
;
97 unsigned int in_martian_dst
;
98 unsigned int in_martian_src
;
100 unsigned int out_slow_tot
;
101 unsigned int out_slow_mc
;
102 unsigned int gc_total
;
103 unsigned int gc_ignored
;
104 unsigned int gc_goal_miss
;
105 unsigned int gc_dst_overflow
;
106 unsigned int in_hlist_search
;
107 unsigned int out_hlist_search
;
110 extern struct ip_rt_acct __percpu
*ip_rt_acct
;
113 extern int ip_rt_init(void);
114 extern void ip_rt_redirect(__be32 old_gw
, __be32 dst
, __be32 new_gw
,
115 __be32 src
, struct net_device
*dev
);
116 extern void rt_cache_flush(struct net
*net
, int how
);
117 extern void rt_cache_flush_batch(struct net
*net
);
118 extern struct rtable
*__ip_route_output_key(struct net
*, const struct flowi4
*flp
);
119 extern struct rtable
*ip_route_output_flow(struct net
*, struct flowi4
*flp
,
121 extern struct dst_entry
*ipv4_blackhole_route(struct net
*net
, struct dst_entry
*dst_orig
);
123 static inline struct rtable
*ip_route_output_key(struct net
*net
, struct flowi4
*flp
)
125 return ip_route_output_flow(net
, flp
, NULL
);
128 static inline struct rtable
*ip_route_output(struct net
*net
, __be32 daddr
,
129 __be32 saddr
, u8 tos
, int oif
)
131 struct flowi4 fl4
= {
137 return ip_route_output_key(net
, &fl4
);
140 static inline struct rtable
*ip_route_output_ports(struct net
*net
, struct sock
*sk
,
141 __be32 daddr
, __be32 saddr
,
142 __be16 dport
, __be16 sport
,
143 __u8 proto
, __u8 tos
, int oif
)
147 flowi4_init_output(&fl4
, oif
, sk
? sk
->sk_mark
: 0, tos
,
148 RT_SCOPE_UNIVERSE
, proto
,
149 sk
? inet_sk_flowi_flags(sk
) : 0,
150 daddr
, saddr
, dport
, sport
);
152 security_sk_classify_flow(sk
, flowi4_to_flowi(&fl4
));
153 return ip_route_output_flow(net
, &fl4
, sk
);
156 static inline struct rtable
*ip_route_output_gre(struct net
*net
,
157 __be32 daddr
, __be32 saddr
,
158 __be32 gre_key
, __u8 tos
, int oif
)
160 struct flowi4 fl4
= {
165 .flowi4_proto
= IPPROTO_GRE
,
166 .fl4_gre_key
= gre_key
,
168 return ip_route_output_key(net
, &fl4
);
171 extern int ip_route_input_common(struct sk_buff
*skb
, __be32 dst
, __be32 src
,
172 u8 tos
, struct net_device
*devin
, bool noref
);
174 static inline int ip_route_input(struct sk_buff
*skb
, __be32 dst
, __be32 src
,
175 u8 tos
, struct net_device
*devin
)
177 return ip_route_input_common(skb
, dst
, src
, tos
, devin
, false);
180 static inline int ip_route_input_noref(struct sk_buff
*skb
, __be32 dst
, __be32 src
,
181 u8 tos
, struct net_device
*devin
)
183 return ip_route_input_common(skb
, dst
, src
, tos
, devin
, true);
186 extern unsigned short ip_rt_frag_needed(struct net
*net
, const struct iphdr
*iph
,
187 unsigned short new_mtu
, struct net_device
*dev
);
188 extern void ip_rt_send_redirect(struct sk_buff
*skb
);
190 extern unsigned inet_addr_type(struct net
*net
, __be32 addr
);
191 extern unsigned inet_dev_addr_type(struct net
*net
, const struct net_device
*dev
, __be32 addr
);
192 extern void ip_rt_multicast_event(struct in_device
*);
193 extern int ip_rt_ioctl(struct net
*, unsigned int cmd
, void __user
*arg
);
194 extern void ip_rt_get_source(u8
*src
, struct rtable
*rt
);
195 extern int ip_rt_dump(struct sk_buff
*skb
, struct netlink_callback
*cb
);
198 extern void fib_add_ifaddr(struct in_ifaddr
*);
199 extern void fib_del_ifaddr(struct in_ifaddr
*, struct in_ifaddr
*);
201 static inline void ip_rt_put(struct rtable
* rt
)
204 dst_release(&rt
->dst
);
207 #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3)
209 extern const __u8 ip_tos2prio
[16];
211 static inline char rt_tos2priority(u8 tos
)
213 return ip_tos2prio
[IPTOS_TOS(tos
)>>1];
216 /* ip_route_connect() and ip_route_newports() work in tandem whilst
217 * binding a socket for a new outgoing connection.
219 * In order to use IPSEC properly, we must, in the end, have a
220 * route that was looked up using all available keys including source
221 * and destination ports.
223 * However, if a source port needs to be allocated (the user specified
224 * a wildcard source port) we need to obtain addressing information
225 * in order to perform that allocation.
227 * So ip_route_connect() looks up a route using wildcarded source and
228 * destination ports in the key, simply so that we can get a pair of
229 * addresses to use for port allocation.
231 * Later, once the ports are allocated, ip_route_newports() will make
232 * another route lookup if needed to make sure we catch any IPSEC
233 * rules keyed on the port information.
235 * The callers allocate the flow key on their stack, and must pass in
236 * the same flowi4 object to both the ip_route_connect() and the
237 * ip_route_newports() calls.
240 static inline void ip_route_connect_init(struct flowi4
*fl4
, __be32 dst
, __be32 src
,
241 u32 tos
, int oif
, u8 protocol
,
242 __be16 sport
, __be16 dport
,
243 struct sock
*sk
, bool can_sleep
)
247 if (inet_sk(sk
)->transparent
)
248 flow_flags
|= FLOWI_FLAG_ANYSRC
;
249 if (protocol
== IPPROTO_TCP
)
250 flow_flags
|= FLOWI_FLAG_PRECOW_METRICS
;
252 flow_flags
|= FLOWI_FLAG_CAN_SLEEP
;
254 flowi4_init_output(fl4
, oif
, sk
->sk_mark
, tos
, RT_SCOPE_UNIVERSE
,
255 protocol
, flow_flags
, dst
, src
, dport
, sport
);
258 static inline struct rtable
*ip_route_connect(struct flowi4
*fl4
,
259 __be32 dst
, __be32 src
, u32 tos
,
260 int oif
, u8 protocol
,
261 __be16 sport
, __be16 dport
,
262 struct sock
*sk
, bool can_sleep
)
264 struct net
*net
= sock_net(sk
);
267 ip_route_connect_init(fl4
, dst
, src
, tos
, oif
, protocol
,
268 sport
, dport
, sk
, can_sleep
);
271 rt
= __ip_route_output_key(net
, fl4
);
274 fl4
->daddr
= rt
->rt_dst
;
275 fl4
->saddr
= rt
->rt_src
;
278 security_sk_classify_flow(sk
, flowi4_to_flowi(fl4
));
279 return ip_route_output_flow(net
, fl4
, sk
);
282 static inline struct rtable
*ip_route_newports(struct flowi4
*fl4
, struct rtable
*rt
,
283 __be16 orig_sport
, __be16 orig_dport
,
284 __be16 sport
, __be16 dport
,
287 if (sport
!= orig_sport
|| dport
!= orig_dport
) {
288 fl4
->fl4_dport
= dport
;
289 fl4
->fl4_sport
= sport
;
291 security_sk_classify_flow(sk
, flowi4_to_flowi(fl4
));
292 return ip_route_output_flow(sock_net(sk
), fl4
, sk
);
297 extern void rt_bind_peer(struct rtable
*rt
, int create
);
299 static inline struct inet_peer
*rt_get_peer(struct rtable
*rt
)
308 static inline int inet_iif(const struct sk_buff
*skb
)
310 return skb_rtable(skb
)->rt_iif
;
313 extern int sysctl_ip_default_ttl
;
315 static inline int ip4_dst_hoplimit(const struct dst_entry
*dst
)
317 int hoplimit
= dst_metric_raw(dst
, RTAX_HOPLIMIT
);
320 hoplimit
= sysctl_ip_default_ttl
;
324 #endif /* _ROUTE_H */