Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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/rcupdate.h>
34#include <linux/route.h>
35#include <linux/ip.h>
36#include <linux/cache.h>
37#include <linux/security.h>
38
39#define RTO_ONLINK 0x01
40
41#define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE))
42
43struct fib_nh;
44struct fib_info;
45struct rtable {
46 struct dst_entry dst;
47
48 int rt_genid;
49 unsigned int rt_flags;
50 __u16 rt_type;
51 __u16 rt_is_input;
52
53 int rt_iif;
54
55 /* Info on neighbour */
56 __be32 rt_gateway;
57
58 /* Miscellaneous cached information */
59 u32 rt_pmtu;
60
61 struct list_head rt_uncached;
62};
63
64static inline bool rt_is_input_route(const struct rtable *rt)
65{
66 return rt->rt_is_input != 0;
67}
68
69static inline bool rt_is_output_route(const struct rtable *rt)
70{
71 return rt->rt_is_input == 0;
72}
73
74static inline __be32 rt_nexthop(const struct rtable *rt, __be32 daddr)
75{
76 if (rt->rt_gateway)
77 return rt->rt_gateway;
78 return daddr;
79}
80
81struct ip_rt_acct {
82 __u32 o_bytes;
83 __u32 o_packets;
84 __u32 i_bytes;
85 __u32 i_packets;
86};
87
88struct rt_cache_stat {
89 unsigned int in_hit;
90 unsigned int in_slow_tot;
91 unsigned int in_slow_mc;
92 unsigned int in_no_route;
93 unsigned int in_brd;
94 unsigned int in_martian_dst;
95 unsigned int in_martian_src;
96 unsigned int out_hit;
97 unsigned int out_slow_tot;
98 unsigned int out_slow_mc;
99 unsigned int gc_total;
100 unsigned int gc_ignored;
101 unsigned int gc_goal_miss;
102 unsigned int gc_dst_overflow;
103 unsigned int in_hlist_search;
104 unsigned int out_hlist_search;
105};
106
107extern struct ip_rt_acct __percpu *ip_rt_acct;
108
109struct in_device;
110extern int ip_rt_init(void);
111extern void rt_cache_flush(struct net *net);
112extern void rt_flush_dev(struct net_device *dev);
113extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
114extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
115 struct sock *sk);
116extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);
117
118static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp)
119{
120 return ip_route_output_flow(net, flp, NULL);
121}
122
123static inline struct rtable *ip_route_output(struct net *net, __be32 daddr,
124 __be32 saddr, u8 tos, int oif)
125{
126 struct flowi4 fl4 = {
127 .flowi4_oif = oif,
128 .flowi4_tos = tos,
129 .daddr = daddr,
130 .saddr = saddr,
131 };
132 return ip_route_output_key(net, &fl4);
133}
134
135static inline struct rtable *ip_route_output_ports(struct net *net, struct flowi4 *fl4,
136 struct sock *sk,
137 __be32 daddr, __be32 saddr,
138 __be16 dport, __be16 sport,
139 __u8 proto, __u8 tos, int oif)
140{
141 flowi4_init_output(fl4, oif, sk ? sk->sk_mark : 0, tos,
142 RT_SCOPE_UNIVERSE, proto,
143 sk ? inet_sk_flowi_flags(sk) : 0,
144 daddr, saddr, dport, sport);
145 if (sk)
146 security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
147 return ip_route_output_flow(net, fl4, sk);
148}
149
150static inline struct rtable *ip_route_output_gre(struct net *net, struct flowi4 *fl4,
151 __be32 daddr, __be32 saddr,
152 __be32 gre_key, __u8 tos, int oif)
153{
154 memset(fl4, 0, sizeof(*fl4));
155 fl4->flowi4_oif = oif;
156 fl4->daddr = daddr;
157 fl4->saddr = saddr;
158 fl4->flowi4_tos = tos;
159 fl4->flowi4_proto = IPPROTO_GRE;
160 fl4->fl4_gre_key = gre_key;
161 return ip_route_output_key(net, fl4);
162}
163
164extern int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src,
165 u8 tos, struct net_device *devin);
166
167static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src,
168 u8 tos, struct net_device *devin)
169{
170 int err;
171
172 rcu_read_lock();
173 err = ip_route_input_noref(skb, dst, src, tos, devin);
174 if (!err)
175 skb_dst_force(skb);
176 rcu_read_unlock();
177
178 return err;
179}
180
181extern void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
182 int oif, u32 mark, u8 protocol, int flow_flags);
183extern void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu);
184extern void ipv4_redirect(struct sk_buff *skb, struct net *net,
185 int oif, u32 mark, u8 protocol, int flow_flags);
186extern void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk);
187extern void ip_rt_send_redirect(struct sk_buff *skb);
188
189extern unsigned int inet_addr_type(struct net *net, __be32 addr);
190extern unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, __be32 addr);
191extern void ip_rt_multicast_event(struct in_device *);
192extern int ip_rt_ioctl(struct net *, unsigned int cmd, void __user *arg);
193extern void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt);
194extern int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb);
195
196struct in_ifaddr;
197extern void fib_add_ifaddr(struct in_ifaddr *);
198extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *);
199
200static inline void ip_rt_put(struct rtable * rt)
201{
202 if (rt)
203 dst_release(&rt->dst);
204}
205
206#define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3)
207
208extern const __u8 ip_tos2prio[16];
209
210static inline char rt_tos2priority(u8 tos)
211{
212 return ip_tos2prio[IPTOS_TOS(tos)>>1];
213}
214
215/* ip_route_connect() and ip_route_newports() work in tandem whilst
216 * binding a socket for a new outgoing connection.
217 *
218 * In order to use IPSEC properly, we must, in the end, have a
219 * route that was looked up using all available keys including source
220 * and destination ports.
221 *
222 * However, if a source port needs to be allocated (the user specified
223 * a wildcard source port) we need to obtain addressing information
224 * in order to perform that allocation.
225 *
226 * So ip_route_connect() looks up a route using wildcarded source and
227 * destination ports in the key, simply so that we can get a pair of
228 * addresses to use for port allocation.
229 *
230 * Later, once the ports are allocated, ip_route_newports() will make
231 * another route lookup if needed to make sure we catch any IPSEC
232 * rules keyed on the port information.
233 *
234 * The callers allocate the flow key on their stack, and must pass in
235 * the same flowi4 object to both the ip_route_connect() and the
236 * ip_route_newports() calls.
237 */
238
239static inline void ip_route_connect_init(struct flowi4 *fl4, __be32 dst, __be32 src,
240 u32 tos, int oif, u8 protocol,
241 __be16 sport, __be16 dport,
242 struct sock *sk, bool can_sleep)
243{
244 __u8 flow_flags = 0;
245
246 if (inet_sk(sk)->transparent)
247 flow_flags |= FLOWI_FLAG_ANYSRC;
248 if (can_sleep)
249 flow_flags |= FLOWI_FLAG_CAN_SLEEP;
250
251 flowi4_init_output(fl4, oif, sk->sk_mark, tos, RT_SCOPE_UNIVERSE,
252 protocol, flow_flags, dst, src, dport, sport);
253}
254
255static inline struct rtable *ip_route_connect(struct flowi4 *fl4,
256 __be32 dst, __be32 src, u32 tos,
257 int oif, u8 protocol,
258 __be16 sport, __be16 dport,
259 struct sock *sk, bool can_sleep)
260{
261 struct net *net = sock_net(sk);
262 struct rtable *rt;
263
264 ip_route_connect_init(fl4, dst, src, tos, oif, protocol,
265 sport, dport, sk, can_sleep);
266
267 if (!dst || !src) {
268 rt = __ip_route_output_key(net, fl4);
269 if (IS_ERR(rt))
270 return rt;
271 ip_rt_put(rt);
272 flowi4_update_output(fl4, oif, tos, fl4->daddr, fl4->saddr);
273 }
274 security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
275 return ip_route_output_flow(net, fl4, sk);
276}
277
278static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable *rt,
279 __be16 orig_sport, __be16 orig_dport,
280 __be16 sport, __be16 dport,
281 struct sock *sk)
282{
283 if (sport != orig_sport || dport != orig_dport) {
284 fl4->fl4_dport = dport;
285 fl4->fl4_sport = sport;
286 ip_rt_put(rt);
287 flowi4_update_output(fl4, sk->sk_bound_dev_if,
288 RT_CONN_FLAGS(sk), fl4->daddr,
289 fl4->saddr);
290 security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
291 return ip_route_output_flow(sock_net(sk), fl4, sk);
292 }
293 return rt;
294}
295
296static inline int inet_iif(const struct sk_buff *skb)
297{
298 int iif = skb_rtable(skb)->rt_iif;
299
300 if (iif)
301 return iif;
302 return skb->skb_iif;
303}
304
305extern int sysctl_ip_default_ttl;
306
307static inline int ip4_dst_hoplimit(const struct dst_entry *dst)
308{
309 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
310
311 if (hoplimit == 0)
312 hoplimit = sysctl_ip_default_ttl;
313 return hoplimit;
314}
315
316#endif /* _ROUTE_H */