Commit | Line | Data |
---|---|---|
2874c5fd | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
1da177e4 LT |
2 | /* |
3 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
4 | * operating system. INET is implemented using the BSD Socket | |
5 | * interface as the means of communication with the user level. | |
6 | * | |
7 | * Definitions for the IP router. | |
8 | * | |
9 | * Version: @(#)route.h 1.0.4 05/27/93 | |
10 | * | |
02c30a84 | 11 | * Authors: Ross Biro |
1da177e4 LT |
12 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
13 | * Fixes: | |
14 | * Alan Cox : Reformatted. Added ip_rt_local() | |
15 | * Alan Cox : Support for TCP parameters. | |
16 | * Alexey Kuznetsov: Major changes for new routing code. | |
17 | * Mike McLagan : Routing by source | |
18 | * Robert Olsson : Added rt_cache statistics | |
1da177e4 LT |
19 | */ |
20 | #ifndef _ROUTE_H | |
21 | #define _ROUTE_H | |
22 | ||
1da177e4 LT |
23 | #include <net/dst.h> |
24 | #include <net/inetpeer.h> | |
25 | #include <net/flow.h> | |
79876874 | 26 | #include <net/inet_sock.h> |
79a13159 | 27 | #include <net/ip_fib.h> |
5c9f7c1d DA |
28 | #include <net/arp.h> |
29 | #include <net/ndisc.h> | |
1da177e4 LT |
30 | #include <linux/in_route.h> |
31 | #include <linux/rtnetlink.h> | |
c6cffba4 | 32 | #include <linux/rcupdate.h> |
1da177e4 LT |
33 | #include <linux/route.h> |
34 | #include <linux/ip.h> | |
35 | #include <linux/cache.h> | |
beb8d13b | 36 | #include <linux/security.h> |
1da177e4 | 37 | |
1da177e4 LT |
38 | #define RTO_ONLINK 0x01 |
39 | ||
1da177e4 | 40 | #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE)) |
aa661581 | 41 | #define RT_CONN_FLAGS_TOS(sk,tos) (RT_TOS(tos) | sock_flag(sk, SOCK_LOCALROUTE)) |
1da177e4 | 42 | |
67e1e2f4 GN |
43 | static inline __u8 ip_sock_rt_scope(const struct sock *sk) |
44 | { | |
45 | if (sock_flag(sk, SOCK_LOCALROUTE)) | |
46 | return RT_SCOPE_LINK; | |
47 | ||
48 | return RT_SCOPE_UNIVERSE; | |
49 | } | |
50 | ||
51 | static inline __u8 ip_sock_rt_tos(const struct sock *sk) | |
52 | { | |
53 | return RT_TOS(inet_sk(sk)->tos); | |
54 | } | |
55 | ||
b6459415 | 56 | struct ip_tunnel_info; |
1da177e4 | 57 | struct fib_nh; |
62fa8a84 | 58 | struct fib_info; |
5055c371 | 59 | struct uncached_list; |
fd2c3ef7 | 60 | struct rtable { |
d8d1f30b | 61 | struct dst_entry dst; |
1da177e4 | 62 | |
29e75252 | 63 | int rt_genid; |
95c96174 | 64 | unsigned int rt_flags; |
1da177e4 | 65 | __u16 rt_type; |
155e8336 | 66 | __u8 rt_is_input; |
77d5bc7e | 67 | __u8 rt_uses_gateway; |
1da177e4 | 68 | |
1da177e4 LT |
69 | int rt_iif; |
70 | ||
77d5bc7e | 71 | u8 rt_gw_family; |
1da177e4 | 72 | /* Info on neighbour */ |
0f5f7d7b DA |
73 | union { |
74 | __be32 rt_gw4; | |
75 | struct in6_addr rt_gw6; | |
76 | }; | |
1da177e4 | 77 | |
1da177e4 | 78 | /* Miscellaneous cached information */ |
d52e5a7e SD |
79 | u32 rt_mtu_locked:1, |
80 | rt_pmtu:31; | |
1da177e4 LT |
81 | }; |
82 | ||
b8400f37 | 83 | static inline bool rt_is_input_route(const struct rtable *rt) |
c7537967 | 84 | { |
9917e1e8 | 85 | return rt->rt_is_input != 0; |
c7537967 DM |
86 | } |
87 | ||
b8400f37 | 88 | static inline bool rt_is_output_route(const struct rtable *rt) |
c7537967 | 89 | { |
9917e1e8 | 90 | return rt->rt_is_input == 0; |
c7537967 DM |
91 | } |
92 | ||
f8126f1d DM |
93 | static inline __be32 rt_nexthop(const struct rtable *rt, __be32 daddr) |
94 | { | |
1550c171 DA |
95 | if (rt->rt_gw_family == AF_INET) |
96 | return rt->rt_gw4; | |
f8126f1d DM |
97 | return daddr; |
98 | } | |
99 | ||
fd2c3ef7 | 100 | struct ip_rt_acct { |
1da177e4 LT |
101 | __u32 o_bytes; |
102 | __u32 o_packets; | |
103 | __u32 i_bytes; | |
104 | __u32 i_packets; | |
105 | }; | |
106 | ||
fd2c3ef7 | 107 | struct rt_cache_stat { |
1da177e4 LT |
108 | unsigned int in_slow_tot; |
109 | unsigned int in_slow_mc; | |
110 | unsigned int in_no_route; | |
111 | unsigned int in_brd; | |
112 | unsigned int in_martian_dst; | |
113 | unsigned int in_martian_src; | |
1da177e4 LT |
114 | unsigned int out_slow_tot; |
115 | unsigned int out_slow_mc; | |
1da177e4 LT |
116 | }; |
117 | ||
7d720c3e | 118 | extern struct ip_rt_acct __percpu *ip_rt_acct; |
1da177e4 LT |
119 | |
120 | struct in_device; | |
2702c4bb JP |
121 | |
122 | int ip_rt_init(void); | |
123 | void rt_cache_flush(struct net *net); | |
124 | void rt_flush_dev(struct net_device *dev); | |
3abd1ade DA |
125 | struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *flp, |
126 | const struct sk_buff *skb); | |
127 | struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4 *flp, | |
128 | struct fib_result *res, | |
129 | const struct sk_buff *skb); | |
79a13159 PN |
130 | |
131 | static inline struct rtable *__ip_route_output_key(struct net *net, | |
132 | struct flowi4 *flp) | |
133 | { | |
3abd1ade | 134 | return ip_route_output_key_hash(net, flp, NULL); |
79a13159 PN |
135 | } |
136 | ||
2702c4bb | 137 | struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp, |
6f9c9615 | 138 | const struct sock *sk); |
571912c6 MV |
139 | struct rtable *ip_route_output_tunnel(struct sk_buff *skb, |
140 | struct net_device *dev, | |
141 | struct net *net, __be32 *saddr, | |
142 | const struct ip_tunnel_info *info, | |
143 | u8 protocol, bool use_cache); | |
144 | ||
2702c4bb JP |
145 | struct dst_entry *ipv4_blackhole_route(struct net *net, |
146 | struct dst_entry *dst_orig); | |
407eadd9 | 147 | |
9d6ec938 | 148 | static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp) |
5bfa787f DM |
149 | { |
150 | return ip_route_output_flow(net, flp, NULL); | |
151 | } | |
152 | ||
78fbfd8a DM |
153 | static inline struct rtable *ip_route_output(struct net *net, __be32 daddr, |
154 | __be32 saddr, u8 tos, int oif) | |
155 | { | |
9d6ec938 DM |
156 | struct flowi4 fl4 = { |
157 | .flowi4_oif = oif, | |
c5d21c4b | 158 | .flowi4_tos = tos, |
9d6ec938 DM |
159 | .daddr = daddr, |
160 | .saddr = saddr, | |
78fbfd8a | 161 | }; |
9d6ec938 | 162 | return ip_route_output_key(net, &fl4); |
78fbfd8a DM |
163 | } |
164 | ||
31e4543d | 165 | static inline struct rtable *ip_route_output_ports(struct net *net, struct flowi4 *fl4, |
8d6eba33 | 166 | const struct sock *sk, |
78fbfd8a DM |
167 | __be32 daddr, __be32 saddr, |
168 | __be16 dport, __be16 sport, | |
169 | __u8 proto, __u8 tos, int oif) | |
170 | { | |
3c5b4d69 | 171 | flowi4_init_output(fl4, oif, sk ? READ_ONCE(sk->sk_mark) : 0, tos, |
94b92b88 DM |
172 | RT_SCOPE_UNIVERSE, proto, |
173 | sk ? inet_sk_flowi_flags(sk) : 0, | |
e2d118a1 | 174 | daddr, saddr, dport, sport, sock_net_uid(net, sk)); |
78fbfd8a | 175 | if (sk) |
3df98d79 | 176 | security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4)); |
31e4543d | 177 | return ip_route_output_flow(net, fl4, sk); |
78fbfd8a DM |
178 | } |
179 | ||
cbb1e85f | 180 | static inline struct rtable *ip_route_output_gre(struct net *net, struct flowi4 *fl4, |
78fbfd8a DM |
181 | __be32 daddr, __be32 saddr, |
182 | __be32 gre_key, __u8 tos, int oif) | |
183 | { | |
cbb1e85f DM |
184 | memset(fl4, 0, sizeof(*fl4)); |
185 | fl4->flowi4_oif = oif; | |
186 | fl4->daddr = daddr; | |
187 | fl4->saddr = saddr; | |
188 | fl4->flowi4_tos = tos; | |
189 | fl4->flowi4_proto = IPPROTO_GRE; | |
190 | fl4->fl4_gre_key = gre_key; | |
191 | return ip_route_output_key(net, fl4); | |
78fbfd8a | 192 | } |
bc044e8d PA |
193 | int ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
194 | u8 tos, struct net_device *dev, | |
195 | struct in_device *in_dev, u32 *itag); | |
2702c4bb JP |
196 | int ip_route_input_noref(struct sk_buff *skb, __be32 dst, __be32 src, |
197 | u8 tos, struct net_device *devin); | |
02b24941 PA |
198 | int ip_route_use_hint(struct sk_buff *skb, __be32 dst, __be32 src, |
199 | u8 tos, struct net_device *devin, | |
200 | const struct sk_buff *hint); | |
201 | ||
c6cffba4 DM |
202 | static inline int ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, |
203 | u8 tos, struct net_device *devin) | |
204 | { | |
205 | int err; | |
206 | ||
207 | rcu_read_lock(); | |
208 | err = ip_route_input_noref(skb, dst, src, tos, devin); | |
64327fc8 | 209 | if (!err) { |
222d7dbd | 210 | skb_dst_force(skb); |
64327fc8 SB |
211 | if (!skb_dst(skb)) |
212 | err = -EINVAL; | |
213 | } | |
c6cffba4 DM |
214 | rcu_read_unlock(); |
215 | ||
216 | return err; | |
217 | } | |
407eadd9 | 218 | |
2702c4bb | 219 | void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, int oif, |
d888f396 | 220 | u8 protocol); |
2702c4bb | 221 | void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu); |
1042caa7 | 222 | void ipv4_redirect(struct sk_buff *skb, struct net *net, int oif, u8 protocol); |
2702c4bb JP |
223 | void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk); |
224 | void ip_rt_send_redirect(struct sk_buff *skb); | |
225 | ||
226 | unsigned int inet_addr_type(struct net *net, __be32 addr); | |
9b8ff518 | 227 | unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id); |
2702c4bb JP |
228 | unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, |
229 | __be32 addr); | |
30bbaa19 DA |
230 | unsigned int inet_addr_type_dev_table(struct net *net, |
231 | const struct net_device *dev, | |
232 | __be32 addr); | |
2702c4bb | 233 | void ip_rt_multicast_event(struct in_device *); |
ca25c300 | 234 | int ip_rt_ioctl(struct net *, unsigned int cmd, struct rtentry *rt); |
2702c4bb | 235 | void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt); |
9ab179d8 | 236 | struct rtable *rt_dst_alloc(struct net_device *dev, |
b5c8b3fe | 237 | unsigned int flags, u16 type, bool noxfrm); |
5b18f128 | 238 | struct rtable *rt_dst_clone(struct net_device *dev, struct rtable *rt); |
1da177e4 | 239 | |
0ff60a45 | 240 | struct in_ifaddr; |
2702c4bb JP |
241 | void fib_add_ifaddr(struct in_ifaddr *); |
242 | void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *); | |
af4d768a | 243 | void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric); |
0ff60a45 | 244 | |
510c321b XL |
245 | void rt_add_uncached_list(struct rtable *rt); |
246 | void rt_del_uncached_list(struct rtable *rt); | |
247 | ||
ee28906f SB |
248 | int fib_dump_info_fnhe(struct sk_buff *skb, struct netlink_callback *cb, |
249 | u32 table_id, struct fib_info *fi, | |
e93fb3e9 | 250 | int *fa_index, int fa_start, unsigned int flags); |
ee28906f | 251 | |
6da025fa | 252 | static inline void ip_rt_put(struct rtable *rt) |
1da177e4 | 253 | { |
6da025fa ED |
254 | /* dst_release() accepts a NULL parameter. |
255 | * We rely on dst being first structure in struct rtable | |
256 | */ | |
257 | BUILD_BUG_ON(offsetof(struct rtable, dst) != 0); | |
258 | dst_release(&rt->dst); | |
1da177e4 LT |
259 | } |
260 | ||
261 | #define IPTOS_RT_MASK (IPTOS_TOS_MASK & ~3) | |
262 | ||
4839c52b | 263 | extern const __u8 ip_tos2prio[16]; |
1da177e4 LT |
264 | |
265 | static inline char rt_tos2priority(u8 tos) | |
266 | { | |
267 | return ip_tos2prio[IPTOS_TOS(tos)>>1]; | |
268 | } | |
269 | ||
2d7192d6 DM |
270 | /* ip_route_connect() and ip_route_newports() work in tandem whilst |
271 | * binding a socket for a new outgoing connection. | |
272 | * | |
273 | * In order to use IPSEC properly, we must, in the end, have a | |
274 | * route that was looked up using all available keys including source | |
275 | * and destination ports. | |
276 | * | |
277 | * However, if a source port needs to be allocated (the user specified | |
278 | * a wildcard source port) we need to obtain addressing information | |
279 | * in order to perform that allocation. | |
280 | * | |
281 | * So ip_route_connect() looks up a route using wildcarded source and | |
282 | * destination ports in the key, simply so that we can get a pair of | |
283 | * addresses to use for port allocation. | |
284 | * | |
285 | * Later, once the ports are allocated, ip_route_newports() will make | |
286 | * another route lookup if needed to make sure we catch any IPSEC | |
287 | * rules keyed on the port information. | |
288 | * | |
289 | * The callers allocate the flow key on their stack, and must pass in | |
290 | * the same flowi4 object to both the ip_route_connect() and the | |
291 | * ip_route_newports() calls. | |
292 | */ | |
293 | ||
67e1e2f4 GN |
294 | static inline void ip_route_connect_init(struct flowi4 *fl4, __be32 dst, |
295 | __be32 src, int oif, u8 protocol, | |
2d7192d6 | 296 | __be16 sport, __be16 dport, |
67e1e2f4 | 297 | const struct sock *sk) |
1da177e4 | 298 | { |
2d7192d6 | 299 | __u8 flow_flags = 0; |
79876874 | 300 | |
4bd0623f | 301 | if (inet_test_bit(TRANSPARENT, sk)) |
94b92b88 | 302 | flow_flags |= FLOWI_FLAG_ANYSRC; |
94b92b88 | 303 | |
3c5b4d69 | 304 | flowi4_init_output(fl4, oif, READ_ONCE(sk->sk_mark), ip_sock_rt_tos(sk), |
67e1e2f4 GN |
305 | ip_sock_rt_scope(sk), protocol, flow_flags, dst, |
306 | src, dport, sport, sk->sk_uid); | |
2d7192d6 DM |
307 | } |
308 | ||
67e1e2f4 GN |
309 | static inline struct rtable *ip_route_connect(struct flowi4 *fl4, __be32 dst, |
310 | __be32 src, int oif, u8 protocol, | |
2d7192d6 | 311 | __be16 sport, __be16 dport, |
8d6eba33 | 312 | const struct sock *sk) |
2d7192d6 DM |
313 | { |
314 | struct net *net = sock_net(sk); | |
315 | struct rtable *rt; | |
316 | ||
67e1e2f4 | 317 | ip_route_connect_init(fl4, dst, src, oif, protocol, sport, dport, sk); |
79876874 | 318 | |
1da177e4 | 319 | if (!dst || !src) { |
2d7192d6 | 320 | rt = __ip_route_output_key(net, fl4); |
b23dd4fe DM |
321 | if (IS_ERR(rt)) |
322 | return rt; | |
b23dd4fe | 323 | ip_rt_put(rt); |
3f06760c | 324 | flowi4_update_output(fl4, oif, fl4->daddr, fl4->saddr); |
1da177e4 | 325 | } |
3df98d79 | 326 | security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4)); |
2d7192d6 | 327 | return ip_route_output_flow(net, fl4, sk); |
1da177e4 LT |
328 | } |
329 | ||
2d7192d6 DM |
330 | static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable *rt, |
331 | __be16 orig_sport, __be16 orig_dport, | |
332 | __be16 sport, __be16 dport, | |
8d6eba33 | 333 | const struct sock *sk) |
1da177e4 | 334 | { |
dca8b089 | 335 | if (sport != orig_sport || dport != orig_dport) { |
2d7192d6 DM |
336 | fl4->fl4_dport = dport; |
337 | fl4->fl4_sport = sport; | |
b23dd4fe | 338 | ip_rt_put(rt); |
3f06760c | 339 | flowi4_update_output(fl4, sk->sk_bound_dev_if, fl4->daddr, |
e6b45241 | 340 | fl4->saddr); |
3df98d79 | 341 | security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4)); |
2d7192d6 | 342 | return ip_route_output_flow(sock_net(sk), fl4, sk); |
1da177e4 | 343 | } |
b23dd4fe | 344 | return rt; |
1da177e4 LT |
345 | } |
346 | ||
1668e010 KK |
347 | static inline int inet_iif(const struct sk_buff *skb) |
348 | { | |
0340d0b9 TH |
349 | struct rtable *rt = skb_rtable(skb); |
350 | ||
351 | if (rt && rt->rt_iif) | |
352 | return rt->rt_iif; | |
13378cad | 353 | |
13378cad | 354 | return skb->skb_iif; |
1668e010 KK |
355 | } |
356 | ||
323e126f DM |
357 | static inline int ip4_dst_hoplimit(const struct dst_entry *dst) |
358 | { | |
359 | int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); | |
fa50d974 | 360 | struct net *net = dev_net(dst->dev); |
323e126f DM |
361 | |
362 | if (hoplimit == 0) | |
8281b7ec | 363 | hoplimit = READ_ONCE(net->ipv4.sysctl_ip_default_ttl); |
323e126f DM |
364 | return hoplimit; |
365 | } | |
366 | ||
5c9f7c1d DA |
367 | static inline struct neighbour *ip_neigh_gw4(struct net_device *dev, |
368 | __be32 daddr) | |
369 | { | |
370 | struct neighbour *neigh; | |
371 | ||
3c42b201 | 372 | neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)daddr); |
5c9f7c1d DA |
373 | if (unlikely(!neigh)) |
374 | neigh = __neigh_create(&arp_tbl, &daddr, dev, false); | |
375 | ||
376 | return neigh; | |
377 | } | |
378 | ||
379 | static inline struct neighbour *ip_neigh_for_gw(struct rtable *rt, | |
380 | struct sk_buff *skb, | |
381 | bool *is_v6gw) | |
382 | { | |
383 | struct net_device *dev = rt->dst.dev; | |
384 | struct neighbour *neigh; | |
385 | ||
386 | if (likely(rt->rt_gw_family == AF_INET)) { | |
387 | neigh = ip_neigh_gw4(dev, rt->rt_gw4); | |
388 | } else if (rt->rt_gw_family == AF_INET6) { | |
389 | neigh = ip_neigh_gw6(dev, &rt->rt_gw6); | |
390 | *is_v6gw = true; | |
391 | } else { | |
392 | neigh = ip_neigh_gw4(dev, ip_hdr(skb)->daddr); | |
393 | } | |
394 | return neigh; | |
395 | } | |
396 | ||
1da177e4 | 397 | #endif /* _ROUTE_H */ |