Commit | Line | Data |
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1da177e4 LT |
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 | * IPv4 Forwarding Information Base: semantics. | |
7 | * | |
1da177e4 LT |
8 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public License | |
12 | * as published by the Free Software Foundation; either version | |
13 | * 2 of the License, or (at your option) any later version. | |
14 | */ | |
15 | ||
1da177e4 | 16 | #include <asm/uaccess.h> |
1da177e4 LT |
17 | #include <linux/bitops.h> |
18 | #include <linux/types.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/jiffies.h> | |
21 | #include <linux/mm.h> | |
22 | #include <linux/string.h> | |
23 | #include <linux/socket.h> | |
24 | #include <linux/sockios.h> | |
25 | #include <linux/errno.h> | |
26 | #include <linux/in.h> | |
27 | #include <linux/inet.h> | |
14c85021 | 28 | #include <linux/inetdevice.h> |
1da177e4 LT |
29 | #include <linux/netdevice.h> |
30 | #include <linux/if_arp.h> | |
31 | #include <linux/proc_fs.h> | |
32 | #include <linux/skbuff.h> | |
1da177e4 | 33 | #include <linux/init.h> |
5a0e3ad6 | 34 | #include <linux/slab.h> |
1da177e4 | 35 | |
14c85021 | 36 | #include <net/arp.h> |
1da177e4 LT |
37 | #include <net/ip.h> |
38 | #include <net/protocol.h> | |
39 | #include <net/route.h> | |
40 | #include <net/tcp.h> | |
41 | #include <net/sock.h> | |
42 | #include <net/ip_fib.h> | |
f21c7bc5 | 43 | #include <net/netlink.h> |
4e902c57 | 44 | #include <net/nexthop.h> |
1da177e4 LT |
45 | |
46 | #include "fib_lookup.h" | |
47 | ||
832b4c5e | 48 | static DEFINE_SPINLOCK(fib_info_lock); |
1da177e4 LT |
49 | static struct hlist_head *fib_info_hash; |
50 | static struct hlist_head *fib_info_laddrhash; | |
123b9731 | 51 | static unsigned int fib_info_hash_size; |
1da177e4 LT |
52 | static unsigned int fib_info_cnt; |
53 | ||
54 | #define DEVINDEX_HASHBITS 8 | |
55 | #define DEVINDEX_HASHSIZE (1U << DEVINDEX_HASHBITS) | |
56 | static struct hlist_head fib_info_devhash[DEVINDEX_HASHSIZE]; | |
57 | ||
58 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
59 | ||
60 | static DEFINE_SPINLOCK(fib_multipath_lock); | |
61 | ||
6a31d2a9 ED |
62 | #define for_nexthops(fi) { \ |
63 | int nhsel; const struct fib_nh *nh; \ | |
64 | for (nhsel = 0, nh = (fi)->fib_nh; \ | |
65 | nhsel < (fi)->fib_nhs; \ | |
66 | nh++, nhsel++) | |
67 | ||
68 | #define change_nexthops(fi) { \ | |
69 | int nhsel; struct fib_nh *nexthop_nh; \ | |
70 | for (nhsel = 0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ | |
71 | nhsel < (fi)->fib_nhs; \ | |
72 | nexthop_nh++, nhsel++) | |
1da177e4 LT |
73 | |
74 | #else /* CONFIG_IP_ROUTE_MULTIPATH */ | |
75 | ||
76 | /* Hope, that gcc will optimize it to get rid of dummy loop */ | |
77 | ||
6a31d2a9 ED |
78 | #define for_nexthops(fi) { \ |
79 | int nhsel; const struct fib_nh *nh = (fi)->fib_nh; \ | |
80 | for (nhsel = 0; nhsel < 1; nhsel++) | |
1da177e4 | 81 | |
6a31d2a9 ED |
82 | #define change_nexthops(fi) { \ |
83 | int nhsel; \ | |
84 | struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ | |
85 | for (nhsel = 0; nhsel < 1; nhsel++) | |
1da177e4 LT |
86 | |
87 | #endif /* CONFIG_IP_ROUTE_MULTIPATH */ | |
88 | ||
89 | #define endfor_nexthops(fi) } | |
90 | ||
91 | ||
3be0686b | 92 | const struct fib_prop fib_props[RTN_MAX + 1] = { |
6a31d2a9 | 93 | [RTN_UNSPEC] = { |
1da177e4 LT |
94 | .error = 0, |
95 | .scope = RT_SCOPE_NOWHERE, | |
6a31d2a9 ED |
96 | }, |
97 | [RTN_UNICAST] = { | |
1da177e4 LT |
98 | .error = 0, |
99 | .scope = RT_SCOPE_UNIVERSE, | |
6a31d2a9 ED |
100 | }, |
101 | [RTN_LOCAL] = { | |
1da177e4 LT |
102 | .error = 0, |
103 | .scope = RT_SCOPE_HOST, | |
6a31d2a9 ED |
104 | }, |
105 | [RTN_BROADCAST] = { | |
1da177e4 LT |
106 | .error = 0, |
107 | .scope = RT_SCOPE_LINK, | |
6a31d2a9 ED |
108 | }, |
109 | [RTN_ANYCAST] = { | |
1da177e4 LT |
110 | .error = 0, |
111 | .scope = RT_SCOPE_LINK, | |
6a31d2a9 ED |
112 | }, |
113 | [RTN_MULTICAST] = { | |
1da177e4 LT |
114 | .error = 0, |
115 | .scope = RT_SCOPE_UNIVERSE, | |
6a31d2a9 ED |
116 | }, |
117 | [RTN_BLACKHOLE] = { | |
1da177e4 LT |
118 | .error = -EINVAL, |
119 | .scope = RT_SCOPE_UNIVERSE, | |
6a31d2a9 ED |
120 | }, |
121 | [RTN_UNREACHABLE] = { | |
1da177e4 LT |
122 | .error = -EHOSTUNREACH, |
123 | .scope = RT_SCOPE_UNIVERSE, | |
6a31d2a9 ED |
124 | }, |
125 | [RTN_PROHIBIT] = { | |
1da177e4 LT |
126 | .error = -EACCES, |
127 | .scope = RT_SCOPE_UNIVERSE, | |
6a31d2a9 ED |
128 | }, |
129 | [RTN_THROW] = { | |
1da177e4 LT |
130 | .error = -EAGAIN, |
131 | .scope = RT_SCOPE_UNIVERSE, | |
6a31d2a9 ED |
132 | }, |
133 | [RTN_NAT] = { | |
1da177e4 LT |
134 | .error = -EINVAL, |
135 | .scope = RT_SCOPE_NOWHERE, | |
6a31d2a9 ED |
136 | }, |
137 | [RTN_XRESOLVE] = { | |
1da177e4 LT |
138 | .error = -EINVAL, |
139 | .scope = RT_SCOPE_NOWHERE, | |
6a31d2a9 | 140 | }, |
1da177e4 LT |
141 | }; |
142 | ||
4895c771 DM |
143 | static void free_nh_exceptions(struct fib_nh *nh) |
144 | { | |
145 | struct fnhe_hash_bucket *hash = nh->nh_exceptions; | |
146 | int i; | |
147 | ||
148 | for (i = 0; i < FNHE_HASH_SIZE; i++) { | |
149 | struct fib_nh_exception *fnhe; | |
150 | ||
151 | fnhe = rcu_dereference(hash[i].chain); | |
152 | while (fnhe) { | |
153 | struct fib_nh_exception *next; | |
154 | ||
155 | next = rcu_dereference(fnhe->fnhe_next); | |
156 | kfree(fnhe); | |
157 | ||
158 | fnhe = next; | |
159 | } | |
160 | } | |
161 | kfree(hash); | |
162 | } | |
163 | ||
1da177e4 | 164 | /* Release a nexthop info record */ |
19c1ea14 YZ |
165 | static void free_fib_info_rcu(struct rcu_head *head) |
166 | { | |
167 | struct fib_info *fi = container_of(head, struct fib_info, rcu); | |
168 | ||
e49cc0da YZ |
169 | change_nexthops(fi) { |
170 | if (nexthop_nh->nh_dev) | |
171 | dev_put(nexthop_nh->nh_dev); | |
4895c771 DM |
172 | if (nexthop_nh->nh_exceptions) |
173 | free_nh_exceptions(nexthop_nh); | |
e49cc0da YZ |
174 | } endfor_nexthops(fi); |
175 | ||
176 | release_net(fi->fib_net); | |
19c1ea14 YZ |
177 | if (fi->fib_metrics != (u32 *) dst_default_metrics) |
178 | kfree(fi->fib_metrics); | |
179 | kfree(fi); | |
180 | } | |
1da177e4 LT |
181 | |
182 | void free_fib_info(struct fib_info *fi) | |
183 | { | |
184 | if (fi->fib_dead == 0) { | |
058bd4d2 | 185 | pr_warn("Freeing alive fib_info %p\n", fi); |
1da177e4 LT |
186 | return; |
187 | } | |
1da177e4 | 188 | fib_info_cnt--; |
7a9bc9b8 DM |
189 | #ifdef CONFIG_IP_ROUTE_CLASSID |
190 | change_nexthops(fi) { | |
191 | if (nexthop_nh->nh_tclassid) | |
f4530fa5 | 192 | fi->fib_net->ipv4.fib_num_tclassid_users--; |
7a9bc9b8 DM |
193 | } endfor_nexthops(fi); |
194 | #endif | |
19c1ea14 | 195 | call_rcu(&fi->rcu, free_fib_info_rcu); |
1da177e4 LT |
196 | } |
197 | ||
198 | void fib_release_info(struct fib_info *fi) | |
199 | { | |
832b4c5e | 200 | spin_lock_bh(&fib_info_lock); |
1da177e4 LT |
201 | if (fi && --fi->fib_treeref == 0) { |
202 | hlist_del(&fi->fib_hash); | |
203 | if (fi->fib_prefsrc) | |
204 | hlist_del(&fi->fib_lhash); | |
205 | change_nexthops(fi) { | |
71fceff0 | 206 | if (!nexthop_nh->nh_dev) |
1da177e4 | 207 | continue; |
71fceff0 | 208 | hlist_del(&nexthop_nh->nh_hash); |
1da177e4 LT |
209 | } endfor_nexthops(fi) |
210 | fi->fib_dead = 1; | |
211 | fib_info_put(fi); | |
212 | } | |
832b4c5e | 213 | spin_unlock_bh(&fib_info_lock); |
1da177e4 LT |
214 | } |
215 | ||
6a31d2a9 | 216 | static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi) |
1da177e4 LT |
217 | { |
218 | const struct fib_nh *onh = ofi->fib_nh; | |
219 | ||
220 | for_nexthops(fi) { | |
221 | if (nh->nh_oif != onh->nh_oif || | |
222 | nh->nh_gw != onh->nh_gw || | |
223 | nh->nh_scope != onh->nh_scope || | |
224 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
225 | nh->nh_weight != onh->nh_weight || | |
226 | #endif | |
c7066f70 | 227 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
228 | nh->nh_tclassid != onh->nh_tclassid || |
229 | #endif | |
6a31d2a9 | 230 | ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD)) |
1da177e4 LT |
231 | return -1; |
232 | onh++; | |
233 | } endfor_nexthops(fi); | |
234 | return 0; | |
235 | } | |
236 | ||
88ebc72f DM |
237 | static inline unsigned int fib_devindex_hashfn(unsigned int val) |
238 | { | |
239 | unsigned int mask = DEVINDEX_HASHSIZE - 1; | |
240 | ||
241 | return (val ^ | |
242 | (val >> DEVINDEX_HASHBITS) ^ | |
243 | (val >> (DEVINDEX_HASHBITS * 2))) & mask; | |
244 | } | |
245 | ||
1da177e4 LT |
246 | static inline unsigned int fib_info_hashfn(const struct fib_info *fi) |
247 | { | |
123b9731 | 248 | unsigned int mask = (fib_info_hash_size - 1); |
1da177e4 LT |
249 | unsigned int val = fi->fib_nhs; |
250 | ||
37e826c5 | 251 | val ^= (fi->fib_protocol << 8) | fi->fib_scope; |
81f7bf6c | 252 | val ^= (__force u32)fi->fib_prefsrc; |
1da177e4 | 253 | val ^= fi->fib_priority; |
88ebc72f DM |
254 | for_nexthops(fi) { |
255 | val ^= fib_devindex_hashfn(nh->nh_oif); | |
256 | } endfor_nexthops(fi) | |
1da177e4 LT |
257 | |
258 | return (val ^ (val >> 7) ^ (val >> 12)) & mask; | |
259 | } | |
260 | ||
261 | static struct fib_info *fib_find_info(const struct fib_info *nfi) | |
262 | { | |
263 | struct hlist_head *head; | |
264 | struct hlist_node *node; | |
265 | struct fib_info *fi; | |
266 | unsigned int hash; | |
267 | ||
268 | hash = fib_info_hashfn(nfi); | |
269 | head = &fib_info_hash[hash]; | |
270 | ||
271 | hlist_for_each_entry(fi, node, head, fib_hash) { | |
09ad9bc7 | 272 | if (!net_eq(fi->fib_net, nfi->fib_net)) |
4814bdbd | 273 | continue; |
1da177e4 LT |
274 | if (fi->fib_nhs != nfi->fib_nhs) |
275 | continue; | |
276 | if (nfi->fib_protocol == fi->fib_protocol && | |
37e826c5 | 277 | nfi->fib_scope == fi->fib_scope && |
1da177e4 LT |
278 | nfi->fib_prefsrc == fi->fib_prefsrc && |
279 | nfi->fib_priority == fi->fib_priority && | |
280 | memcmp(nfi->fib_metrics, fi->fib_metrics, | |
fcd13f42 | 281 | sizeof(u32) * RTAX_MAX) == 0 && |
6a31d2a9 | 282 | ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 && |
1da177e4 LT |
283 | (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0)) |
284 | return fi; | |
285 | } | |
286 | ||
287 | return NULL; | |
288 | } | |
289 | ||
1da177e4 | 290 | /* Check, that the gateway is already configured. |
6a31d2a9 | 291 | * Used only by redirect accept routine. |
1da177e4 | 292 | */ |
d878e72e | 293 | int ip_fib_check_default(__be32 gw, struct net_device *dev) |
1da177e4 LT |
294 | { |
295 | struct hlist_head *head; | |
296 | struct hlist_node *node; | |
297 | struct fib_nh *nh; | |
298 | unsigned int hash; | |
299 | ||
832b4c5e | 300 | spin_lock(&fib_info_lock); |
1da177e4 LT |
301 | |
302 | hash = fib_devindex_hashfn(dev->ifindex); | |
303 | head = &fib_info_devhash[hash]; | |
304 | hlist_for_each_entry(nh, node, head, nh_hash) { | |
305 | if (nh->nh_dev == dev && | |
306 | nh->nh_gw == gw && | |
6a31d2a9 | 307 | !(nh->nh_flags & RTNH_F_DEAD)) { |
832b4c5e | 308 | spin_unlock(&fib_info_lock); |
1da177e4 LT |
309 | return 0; |
310 | } | |
311 | } | |
312 | ||
832b4c5e | 313 | spin_unlock(&fib_info_lock); |
1da177e4 LT |
314 | |
315 | return -1; | |
316 | } | |
317 | ||
339bf98f TG |
318 | static inline size_t fib_nlmsg_size(struct fib_info *fi) |
319 | { | |
320 | size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg)) | |
321 | + nla_total_size(4) /* RTA_TABLE */ | |
322 | + nla_total_size(4) /* RTA_DST */ | |
323 | + nla_total_size(4) /* RTA_PRIORITY */ | |
324 | + nla_total_size(4); /* RTA_PREFSRC */ | |
325 | ||
326 | /* space for nested metrics */ | |
327 | payload += nla_total_size((RTAX_MAX * nla_total_size(4))); | |
328 | ||
329 | if (fi->fib_nhs) { | |
330 | /* Also handles the special case fib_nhs == 1 */ | |
331 | ||
332 | /* each nexthop is packed in an attribute */ | |
333 | size_t nhsize = nla_total_size(sizeof(struct rtnexthop)); | |
334 | ||
335 | /* may contain flow and gateway attribute */ | |
336 | nhsize += 2 * nla_total_size(4); | |
337 | ||
338 | /* all nexthops are packed in a nested attribute */ | |
339 | payload += nla_total_size(fi->fib_nhs * nhsize); | |
340 | } | |
341 | ||
342 | return payload; | |
343 | } | |
344 | ||
81f7bf6c | 345 | void rtmsg_fib(int event, __be32 key, struct fib_alias *fa, |
b8f55831 MK |
346 | int dst_len, u32 tb_id, struct nl_info *info, |
347 | unsigned int nlm_flags) | |
1da177e4 LT |
348 | { |
349 | struct sk_buff *skb; | |
4e902c57 | 350 | u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; |
f21c7bc5 | 351 | int err = -ENOBUFS; |
1da177e4 | 352 | |
339bf98f | 353 | skb = nlmsg_new(fib_nlmsg_size(fa->fa_info), GFP_KERNEL); |
f21c7bc5 TG |
354 | if (skb == NULL) |
355 | goto errout; | |
1da177e4 | 356 | |
4e902c57 | 357 | err = fib_dump_info(skb, info->pid, seq, event, tb_id, |
37e826c5 | 358 | fa->fa_type, key, dst_len, |
b8f55831 | 359 | fa->fa_tos, fa->fa_info, nlm_flags); |
26932566 PM |
360 | if (err < 0) { |
361 | /* -EMSGSIZE implies BUG in fib_nlmsg_size() */ | |
362 | WARN_ON(err == -EMSGSIZE); | |
363 | kfree_skb(skb); | |
364 | goto errout; | |
365 | } | |
1ce85fe4 PNA |
366 | rtnl_notify(skb, info->nl_net, info->pid, RTNLGRP_IPV4_ROUTE, |
367 | info->nlh, GFP_KERNEL); | |
368 | return; | |
f21c7bc5 TG |
369 | errout: |
370 | if (err < 0) | |
4d1169c1 | 371 | rtnl_set_sk_err(info->nl_net, RTNLGRP_IPV4_ROUTE, err); |
1da177e4 LT |
372 | } |
373 | ||
374 | /* Return the first fib alias matching TOS with | |
375 | * priority less than or equal to PRIO. | |
376 | */ | |
377 | struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio) | |
378 | { | |
379 | if (fah) { | |
380 | struct fib_alias *fa; | |
381 | list_for_each_entry(fa, fah, fa_list) { | |
382 | if (fa->fa_tos > tos) | |
383 | continue; | |
384 | if (fa->fa_info->fib_priority >= prio || | |
385 | fa->fa_tos < tos) | |
386 | return fa; | |
387 | } | |
388 | } | |
389 | return NULL; | |
390 | } | |
391 | ||
392 | int fib_detect_death(struct fib_info *fi, int order, | |
c17860a0 | 393 | struct fib_info **last_resort, int *last_idx, int dflt) |
1da177e4 LT |
394 | { |
395 | struct neighbour *n; | |
396 | int state = NUD_NONE; | |
397 | ||
398 | n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev); | |
399 | if (n) { | |
400 | state = n->nud_state; | |
401 | neigh_release(n); | |
402 | } | |
d9319100 | 403 | if (state == NUD_REACHABLE) |
1da177e4 | 404 | return 0; |
6a31d2a9 | 405 | if ((state & NUD_VALID) && order != dflt) |
1da177e4 | 406 | return 0; |
6a31d2a9 ED |
407 | if ((state & NUD_VALID) || |
408 | (*last_idx < 0 && order > dflt)) { | |
1da177e4 LT |
409 | *last_resort = fi; |
410 | *last_idx = order; | |
411 | } | |
412 | return 1; | |
413 | } | |
414 | ||
415 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
416 | ||
4e902c57 | 417 | static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining) |
1da177e4 LT |
418 | { |
419 | int nhs = 0; | |
1da177e4 | 420 | |
4e902c57 | 421 | while (rtnh_ok(rtnh, remaining)) { |
1da177e4 | 422 | nhs++; |
4e902c57 TG |
423 | rtnh = rtnh_next(rtnh, &remaining); |
424 | } | |
425 | ||
426 | /* leftover implies invalid nexthop configuration, discard it */ | |
427 | return remaining > 0 ? 0 : nhs; | |
1da177e4 LT |
428 | } |
429 | ||
4e902c57 TG |
430 | static int fib_get_nhs(struct fib_info *fi, struct rtnexthop *rtnh, |
431 | int remaining, struct fib_config *cfg) | |
1da177e4 | 432 | { |
1da177e4 | 433 | change_nexthops(fi) { |
4e902c57 TG |
434 | int attrlen; |
435 | ||
436 | if (!rtnh_ok(rtnh, remaining)) | |
1da177e4 | 437 | return -EINVAL; |
4e902c57 | 438 | |
71fceff0 DM |
439 | nexthop_nh->nh_flags = |
440 | (cfg->fc_flags & ~0xFF) | rtnh->rtnh_flags; | |
441 | nexthop_nh->nh_oif = rtnh->rtnh_ifindex; | |
442 | nexthop_nh->nh_weight = rtnh->rtnh_hops + 1; | |
4e902c57 TG |
443 | |
444 | attrlen = rtnh_attrlen(rtnh); | |
445 | if (attrlen > 0) { | |
446 | struct nlattr *nla, *attrs = rtnh_attrs(rtnh); | |
447 | ||
448 | nla = nla_find(attrs, attrlen, RTA_GATEWAY); | |
71fceff0 | 449 | nexthop_nh->nh_gw = nla ? nla_get_be32(nla) : 0; |
c7066f70 | 450 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 | 451 | nla = nla_find(attrs, attrlen, RTA_FLOW); |
71fceff0 | 452 | nexthop_nh->nh_tclassid = nla ? nla_get_u32(nla) : 0; |
7a9bc9b8 | 453 | if (nexthop_nh->nh_tclassid) |
f4530fa5 | 454 | fi->fib_net->ipv4.fib_num_tclassid_users++; |
1da177e4 LT |
455 | #endif |
456 | } | |
4e902c57 TG |
457 | |
458 | rtnh = rtnh_next(rtnh, &remaining); | |
1da177e4 | 459 | } endfor_nexthops(fi); |
4e902c57 | 460 | |
1da177e4 LT |
461 | return 0; |
462 | } | |
463 | ||
464 | #endif | |
465 | ||
4e902c57 | 466 | int fib_nh_match(struct fib_config *cfg, struct fib_info *fi) |
1da177e4 LT |
467 | { |
468 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
4e902c57 TG |
469 | struct rtnexthop *rtnh; |
470 | int remaining; | |
1da177e4 LT |
471 | #endif |
472 | ||
4e902c57 | 473 | if (cfg->fc_priority && cfg->fc_priority != fi->fib_priority) |
1da177e4 LT |
474 | return 1; |
475 | ||
4e902c57 TG |
476 | if (cfg->fc_oif || cfg->fc_gw) { |
477 | if ((!cfg->fc_oif || cfg->fc_oif == fi->fib_nh->nh_oif) && | |
478 | (!cfg->fc_gw || cfg->fc_gw == fi->fib_nh->nh_gw)) | |
1da177e4 LT |
479 | return 0; |
480 | return 1; | |
481 | } | |
482 | ||
483 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
4e902c57 | 484 | if (cfg->fc_mp == NULL) |
1da177e4 | 485 | return 0; |
4e902c57 TG |
486 | |
487 | rtnh = cfg->fc_mp; | |
488 | remaining = cfg->fc_mp_len; | |
e905a9ed | 489 | |
1da177e4 | 490 | for_nexthops(fi) { |
4e902c57 | 491 | int attrlen; |
1da177e4 | 492 | |
4e902c57 | 493 | if (!rtnh_ok(rtnh, remaining)) |
1da177e4 | 494 | return -EINVAL; |
4e902c57 TG |
495 | |
496 | if (rtnh->rtnh_ifindex && rtnh->rtnh_ifindex != nh->nh_oif) | |
1da177e4 | 497 | return 1; |
4e902c57 TG |
498 | |
499 | attrlen = rtnh_attrlen(rtnh); | |
500 | if (attrlen < 0) { | |
501 | struct nlattr *nla, *attrs = rtnh_attrs(rtnh); | |
502 | ||
503 | nla = nla_find(attrs, attrlen, RTA_GATEWAY); | |
17fb2c64 | 504 | if (nla && nla_get_be32(nla) != nh->nh_gw) |
1da177e4 | 505 | return 1; |
c7066f70 | 506 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 TG |
507 | nla = nla_find(attrs, attrlen, RTA_FLOW); |
508 | if (nla && nla_get_u32(nla) != nh->nh_tclassid) | |
1da177e4 LT |
509 | return 1; |
510 | #endif | |
511 | } | |
4e902c57 TG |
512 | |
513 | rtnh = rtnh_next(rtnh, &remaining); | |
1da177e4 LT |
514 | } endfor_nexthops(fi); |
515 | #endif | |
516 | return 0; | |
517 | } | |
518 | ||
519 | ||
520 | /* | |
6a31d2a9 ED |
521 | * Picture |
522 | * ------- | |
523 | * | |
524 | * Semantics of nexthop is very messy by historical reasons. | |
525 | * We have to take into account, that: | |
526 | * a) gateway can be actually local interface address, | |
527 | * so that gatewayed route is direct. | |
528 | * b) gateway must be on-link address, possibly | |
529 | * described not by an ifaddr, but also by a direct route. | |
530 | * c) If both gateway and interface are specified, they should not | |
531 | * contradict. | |
532 | * d) If we use tunnel routes, gateway could be not on-link. | |
533 | * | |
534 | * Attempt to reconcile all of these (alas, self-contradictory) conditions | |
535 | * results in pretty ugly and hairy code with obscure logic. | |
536 | * | |
537 | * I chose to generalized it instead, so that the size | |
538 | * of code does not increase practically, but it becomes | |
539 | * much more general. | |
540 | * Every prefix is assigned a "scope" value: "host" is local address, | |
541 | * "link" is direct route, | |
542 | * [ ... "site" ... "interior" ... ] | |
543 | * and "universe" is true gateway route with global meaning. | |
544 | * | |
545 | * Every prefix refers to a set of "nexthop"s (gw, oif), | |
546 | * where gw must have narrower scope. This recursion stops | |
547 | * when gw has LOCAL scope or if "nexthop" is declared ONLINK, | |
548 | * which means that gw is forced to be on link. | |
549 | * | |
550 | * Code is still hairy, but now it is apparently logically | |
551 | * consistent and very flexible. F.e. as by-product it allows | |
552 | * to co-exists in peace independent exterior and interior | |
553 | * routing processes. | |
554 | * | |
555 | * Normally it looks as following. | |
556 | * | |
557 | * {universe prefix} -> (gw, oif) [scope link] | |
558 | * | | |
559 | * |-> {link prefix} -> (gw, oif) [scope local] | |
560 | * | | |
561 | * |-> {local prefix} (terminal node) | |
1da177e4 | 562 | */ |
4e902c57 TG |
563 | static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, |
564 | struct fib_nh *nh) | |
1da177e4 LT |
565 | { |
566 | int err; | |
86167a37 | 567 | struct net *net; |
6a31d2a9 | 568 | struct net_device *dev; |
1da177e4 | 569 | |
86167a37 | 570 | net = cfg->fc_nlinfo.nl_net; |
1da177e4 LT |
571 | if (nh->nh_gw) { |
572 | struct fib_result res; | |
573 | ||
6a31d2a9 | 574 | if (nh->nh_flags & RTNH_F_ONLINK) { |
1da177e4 | 575 | |
4e902c57 | 576 | if (cfg->fc_scope >= RT_SCOPE_LINK) |
1da177e4 | 577 | return -EINVAL; |
86167a37 | 578 | if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST) |
1da177e4 | 579 | return -EINVAL; |
6a31d2a9 ED |
580 | dev = __dev_get_by_index(net, nh->nh_oif); |
581 | if (!dev) | |
1da177e4 | 582 | return -ENODEV; |
6a31d2a9 | 583 | if (!(dev->flags & IFF_UP)) |
1da177e4 LT |
584 | return -ENETDOWN; |
585 | nh->nh_dev = dev; | |
586 | dev_hold(dev); | |
587 | nh->nh_scope = RT_SCOPE_LINK; | |
588 | return 0; | |
589 | } | |
ebc0ffae | 590 | rcu_read_lock(); |
1da177e4 | 591 | { |
9ade2286 DM |
592 | struct flowi4 fl4 = { |
593 | .daddr = nh->nh_gw, | |
594 | .flowi4_scope = cfg->fc_scope + 1, | |
595 | .flowi4_oif = nh->nh_oif, | |
4e902c57 | 596 | }; |
1da177e4 LT |
597 | |
598 | /* It is not necessary, but requires a bit of thinking */ | |
9ade2286 DM |
599 | if (fl4.flowi4_scope < RT_SCOPE_LINK) |
600 | fl4.flowi4_scope = RT_SCOPE_LINK; | |
601 | err = fib_lookup(net, &fl4, &res); | |
ebc0ffae ED |
602 | if (err) { |
603 | rcu_read_unlock(); | |
1da177e4 | 604 | return err; |
ebc0ffae | 605 | } |
1da177e4 LT |
606 | } |
607 | err = -EINVAL; | |
608 | if (res.type != RTN_UNICAST && res.type != RTN_LOCAL) | |
609 | goto out; | |
610 | nh->nh_scope = res.scope; | |
611 | nh->nh_oif = FIB_RES_OIF(res); | |
6a31d2a9 ED |
612 | nh->nh_dev = dev = FIB_RES_DEV(res); |
613 | if (!dev) | |
1da177e4 | 614 | goto out; |
6a31d2a9 | 615 | dev_hold(dev); |
8723e1b4 | 616 | err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN; |
1da177e4 LT |
617 | } else { |
618 | struct in_device *in_dev; | |
619 | ||
6a31d2a9 | 620 | if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK)) |
1da177e4 LT |
621 | return -EINVAL; |
622 | ||
8723e1b4 ED |
623 | rcu_read_lock(); |
624 | err = -ENODEV; | |
86167a37 | 625 | in_dev = inetdev_by_index(net, nh->nh_oif); |
1da177e4 | 626 | if (in_dev == NULL) |
8723e1b4 ED |
627 | goto out; |
628 | err = -ENETDOWN; | |
629 | if (!(in_dev->dev->flags & IFF_UP)) | |
630 | goto out; | |
1da177e4 LT |
631 | nh->nh_dev = in_dev->dev; |
632 | dev_hold(nh->nh_dev); | |
633 | nh->nh_scope = RT_SCOPE_HOST; | |
8723e1b4 | 634 | err = 0; |
1da177e4 | 635 | } |
8723e1b4 ED |
636 | out: |
637 | rcu_read_unlock(); | |
638 | return err; | |
1da177e4 LT |
639 | } |
640 | ||
81f7bf6c | 641 | static inline unsigned int fib_laddr_hashfn(__be32 val) |
1da177e4 | 642 | { |
123b9731 | 643 | unsigned int mask = (fib_info_hash_size - 1); |
1da177e4 | 644 | |
6a31d2a9 ED |
645 | return ((__force u32)val ^ |
646 | ((__force u32)val >> 7) ^ | |
647 | ((__force u32)val >> 14)) & mask; | |
1da177e4 LT |
648 | } |
649 | ||
123b9731 | 650 | static struct hlist_head *fib_info_hash_alloc(int bytes) |
1da177e4 LT |
651 | { |
652 | if (bytes <= PAGE_SIZE) | |
88f83491 | 653 | return kzalloc(bytes, GFP_KERNEL); |
1da177e4 LT |
654 | else |
655 | return (struct hlist_head *) | |
6a31d2a9 ED |
656 | __get_free_pages(GFP_KERNEL | __GFP_ZERO, |
657 | get_order(bytes)); | |
1da177e4 LT |
658 | } |
659 | ||
123b9731 | 660 | static void fib_info_hash_free(struct hlist_head *hash, int bytes) |
1da177e4 LT |
661 | { |
662 | if (!hash) | |
663 | return; | |
664 | ||
665 | if (bytes <= PAGE_SIZE) | |
666 | kfree(hash); | |
667 | else | |
668 | free_pages((unsigned long) hash, get_order(bytes)); | |
669 | } | |
670 | ||
123b9731 DM |
671 | static void fib_info_hash_move(struct hlist_head *new_info_hash, |
672 | struct hlist_head *new_laddrhash, | |
673 | unsigned int new_size) | |
1da177e4 | 674 | { |
b7656e7f | 675 | struct hlist_head *old_info_hash, *old_laddrhash; |
123b9731 | 676 | unsigned int old_size = fib_info_hash_size; |
b7656e7f | 677 | unsigned int i, bytes; |
1da177e4 | 678 | |
832b4c5e | 679 | spin_lock_bh(&fib_info_lock); |
b7656e7f DM |
680 | old_info_hash = fib_info_hash; |
681 | old_laddrhash = fib_info_laddrhash; | |
123b9731 | 682 | fib_info_hash_size = new_size; |
1da177e4 LT |
683 | |
684 | for (i = 0; i < old_size; i++) { | |
685 | struct hlist_head *head = &fib_info_hash[i]; | |
686 | struct hlist_node *node, *n; | |
687 | struct fib_info *fi; | |
688 | ||
689 | hlist_for_each_entry_safe(fi, node, n, head, fib_hash) { | |
690 | struct hlist_head *dest; | |
691 | unsigned int new_hash; | |
692 | ||
693 | hlist_del(&fi->fib_hash); | |
694 | ||
695 | new_hash = fib_info_hashfn(fi); | |
696 | dest = &new_info_hash[new_hash]; | |
697 | hlist_add_head(&fi->fib_hash, dest); | |
698 | } | |
699 | } | |
700 | fib_info_hash = new_info_hash; | |
701 | ||
702 | for (i = 0; i < old_size; i++) { | |
703 | struct hlist_head *lhead = &fib_info_laddrhash[i]; | |
704 | struct hlist_node *node, *n; | |
705 | struct fib_info *fi; | |
706 | ||
707 | hlist_for_each_entry_safe(fi, node, n, lhead, fib_lhash) { | |
708 | struct hlist_head *ldest; | |
709 | unsigned int new_hash; | |
710 | ||
711 | hlist_del(&fi->fib_lhash); | |
712 | ||
713 | new_hash = fib_laddr_hashfn(fi->fib_prefsrc); | |
714 | ldest = &new_laddrhash[new_hash]; | |
715 | hlist_add_head(&fi->fib_lhash, ldest); | |
716 | } | |
717 | } | |
718 | fib_info_laddrhash = new_laddrhash; | |
719 | ||
832b4c5e | 720 | spin_unlock_bh(&fib_info_lock); |
b7656e7f DM |
721 | |
722 | bytes = old_size * sizeof(struct hlist_head *); | |
123b9731 DM |
723 | fib_info_hash_free(old_info_hash, bytes); |
724 | fib_info_hash_free(old_laddrhash, bytes); | |
1da177e4 LT |
725 | } |
726 | ||
436c3b66 DM |
727 | __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh) |
728 | { | |
729 | nh->nh_saddr = inet_select_addr(nh->nh_dev, | |
730 | nh->nh_gw, | |
37e826c5 | 731 | nh->nh_parent->fib_scope); |
436c3b66 DM |
732 | nh->nh_saddr_genid = atomic_read(&net->ipv4.dev_addr_genid); |
733 | ||
734 | return nh->nh_saddr; | |
735 | } | |
736 | ||
4e902c57 | 737 | struct fib_info *fib_create_info(struct fib_config *cfg) |
1da177e4 LT |
738 | { |
739 | int err; | |
740 | struct fib_info *fi = NULL; | |
741 | struct fib_info *ofi; | |
1da177e4 | 742 | int nhs = 1; |
7462bd74 | 743 | struct net *net = cfg->fc_nlinfo.nl_net; |
1da177e4 | 744 | |
4c8237cd DM |
745 | if (cfg->fc_type > RTN_MAX) |
746 | goto err_inval; | |
747 | ||
1da177e4 | 748 | /* Fast check to catch the most weird cases */ |
4e902c57 | 749 | if (fib_props[cfg->fc_type].scope > cfg->fc_scope) |
1da177e4 LT |
750 | goto err_inval; |
751 | ||
752 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
4e902c57 TG |
753 | if (cfg->fc_mp) { |
754 | nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len); | |
1da177e4 LT |
755 | if (nhs == 0) |
756 | goto err_inval; | |
757 | } | |
758 | #endif | |
1da177e4 LT |
759 | |
760 | err = -ENOBUFS; | |
123b9731 DM |
761 | if (fib_info_cnt >= fib_info_hash_size) { |
762 | unsigned int new_size = fib_info_hash_size << 1; | |
1da177e4 LT |
763 | struct hlist_head *new_info_hash; |
764 | struct hlist_head *new_laddrhash; | |
765 | unsigned int bytes; | |
766 | ||
767 | if (!new_size) | |
768 | new_size = 1; | |
769 | bytes = new_size * sizeof(struct hlist_head *); | |
123b9731 DM |
770 | new_info_hash = fib_info_hash_alloc(bytes); |
771 | new_laddrhash = fib_info_hash_alloc(bytes); | |
1da177e4 | 772 | if (!new_info_hash || !new_laddrhash) { |
123b9731 DM |
773 | fib_info_hash_free(new_info_hash, bytes); |
774 | fib_info_hash_free(new_laddrhash, bytes); | |
88f83491 | 775 | } else |
123b9731 | 776 | fib_info_hash_move(new_info_hash, new_laddrhash, new_size); |
1da177e4 | 777 | |
123b9731 | 778 | if (!fib_info_hash_size) |
1da177e4 LT |
779 | goto failure; |
780 | } | |
781 | ||
0da974f4 | 782 | fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct fib_nh), GFP_KERNEL); |
1da177e4 LT |
783 | if (fi == NULL) |
784 | goto failure; | |
725d1e1b DM |
785 | if (cfg->fc_mx) { |
786 | fi->fib_metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL); | |
787 | if (!fi->fib_metrics) | |
788 | goto failure; | |
789 | } else | |
790 | fi->fib_metrics = (u32 *) dst_default_metrics; | |
1da177e4 | 791 | fib_info_cnt++; |
1da177e4 | 792 | |
57d7a600 | 793 | fi->fib_net = hold_net(net); |
4e902c57 | 794 | fi->fib_protocol = cfg->fc_protocol; |
37e826c5 | 795 | fi->fib_scope = cfg->fc_scope; |
4e902c57 TG |
796 | fi->fib_flags = cfg->fc_flags; |
797 | fi->fib_priority = cfg->fc_priority; | |
798 | fi->fib_prefsrc = cfg->fc_prefsrc; | |
1da177e4 LT |
799 | |
800 | fi->fib_nhs = nhs; | |
801 | change_nexthops(fi) { | |
71fceff0 | 802 | nexthop_nh->nh_parent = fi; |
1da177e4 LT |
803 | } endfor_nexthops(fi) |
804 | ||
4e902c57 TG |
805 | if (cfg->fc_mx) { |
806 | struct nlattr *nla; | |
807 | int remaining; | |
808 | ||
809 | nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { | |
8f4c1f9b | 810 | int type = nla_type(nla); |
4e902c57 TG |
811 | |
812 | if (type) { | |
6fac2625 DM |
813 | u32 val; |
814 | ||
4e902c57 | 815 | if (type > RTAX_MAX) |
1da177e4 | 816 | goto err_inval; |
6fac2625 DM |
817 | val = nla_get_u32(nla); |
818 | if (type == RTAX_ADVMSS && val > 65535 - 40) | |
819 | val = 65535 - 40; | |
710ab6c0 DM |
820 | if (type == RTAX_MTU && val > 65535 - 15) |
821 | val = 65535 - 15; | |
6fac2625 | 822 | fi->fib_metrics[type - 1] = val; |
1da177e4 | 823 | } |
1da177e4 LT |
824 | } |
825 | } | |
1da177e4 | 826 | |
4e902c57 | 827 | if (cfg->fc_mp) { |
1da177e4 | 828 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
4e902c57 TG |
829 | err = fib_get_nhs(fi, cfg->fc_mp, cfg->fc_mp_len, cfg); |
830 | if (err != 0) | |
1da177e4 | 831 | goto failure; |
4e902c57 | 832 | if (cfg->fc_oif && fi->fib_nh->nh_oif != cfg->fc_oif) |
1da177e4 | 833 | goto err_inval; |
4e902c57 | 834 | if (cfg->fc_gw && fi->fib_nh->nh_gw != cfg->fc_gw) |
1da177e4 | 835 | goto err_inval; |
c7066f70 | 836 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 | 837 | if (cfg->fc_flow && fi->fib_nh->nh_tclassid != cfg->fc_flow) |
1da177e4 LT |
838 | goto err_inval; |
839 | #endif | |
840 | #else | |
841 | goto err_inval; | |
842 | #endif | |
843 | } else { | |
844 | struct fib_nh *nh = fi->fib_nh; | |
4e902c57 TG |
845 | |
846 | nh->nh_oif = cfg->fc_oif; | |
847 | nh->nh_gw = cfg->fc_gw; | |
848 | nh->nh_flags = cfg->fc_flags; | |
c7066f70 | 849 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 | 850 | nh->nh_tclassid = cfg->fc_flow; |
7a9bc9b8 | 851 | if (nh->nh_tclassid) |
f4530fa5 | 852 | fi->fib_net->ipv4.fib_num_tclassid_users++; |
1da177e4 | 853 | #endif |
1da177e4 LT |
854 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
855 | nh->nh_weight = 1; | |
856 | #endif | |
857 | } | |
858 | ||
4e902c57 TG |
859 | if (fib_props[cfg->fc_type].error) { |
860 | if (cfg->fc_gw || cfg->fc_oif || cfg->fc_mp) | |
1da177e4 LT |
861 | goto err_inval; |
862 | goto link_it; | |
4c8237cd DM |
863 | } else { |
864 | switch (cfg->fc_type) { | |
865 | case RTN_UNICAST: | |
866 | case RTN_LOCAL: | |
867 | case RTN_BROADCAST: | |
868 | case RTN_ANYCAST: | |
869 | case RTN_MULTICAST: | |
870 | break; | |
871 | default: | |
872 | goto err_inval; | |
873 | } | |
1da177e4 LT |
874 | } |
875 | ||
4e902c57 | 876 | if (cfg->fc_scope > RT_SCOPE_HOST) |
1da177e4 LT |
877 | goto err_inval; |
878 | ||
4e902c57 | 879 | if (cfg->fc_scope == RT_SCOPE_HOST) { |
1da177e4 LT |
880 | struct fib_nh *nh = fi->fib_nh; |
881 | ||
882 | /* Local address is added. */ | |
883 | if (nhs != 1 || nh->nh_gw) | |
884 | goto err_inval; | |
885 | nh->nh_scope = RT_SCOPE_NOWHERE; | |
7462bd74 | 886 | nh->nh_dev = dev_get_by_index(net, fi->fib_nh->nh_oif); |
1da177e4 LT |
887 | err = -ENODEV; |
888 | if (nh->nh_dev == NULL) | |
889 | goto failure; | |
890 | } else { | |
891 | change_nexthops(fi) { | |
6a31d2a9 ED |
892 | err = fib_check_nh(cfg, fi, nexthop_nh); |
893 | if (err != 0) | |
1da177e4 LT |
894 | goto failure; |
895 | } endfor_nexthops(fi) | |
896 | } | |
897 | ||
898 | if (fi->fib_prefsrc) { | |
4e902c57 TG |
899 | if (cfg->fc_type != RTN_LOCAL || !cfg->fc_dst || |
900 | fi->fib_prefsrc != cfg->fc_dst) | |
7462bd74 | 901 | if (inet_addr_type(net, fi->fib_prefsrc) != RTN_LOCAL) |
1da177e4 LT |
902 | goto err_inval; |
903 | } | |
904 | ||
1fc050a1 | 905 | change_nexthops(fi) { |
436c3b66 | 906 | fib_info_update_nh_saddr(net, nexthop_nh); |
1fc050a1 DM |
907 | } endfor_nexthops(fi) |
908 | ||
1da177e4 | 909 | link_it: |
6a31d2a9 ED |
910 | ofi = fib_find_info(fi); |
911 | if (ofi) { | |
1da177e4 LT |
912 | fi->fib_dead = 1; |
913 | free_fib_info(fi); | |
914 | ofi->fib_treeref++; | |
915 | return ofi; | |
916 | } | |
917 | ||
918 | fi->fib_treeref++; | |
919 | atomic_inc(&fi->fib_clntref); | |
832b4c5e | 920 | spin_lock_bh(&fib_info_lock); |
1da177e4 LT |
921 | hlist_add_head(&fi->fib_hash, |
922 | &fib_info_hash[fib_info_hashfn(fi)]); | |
923 | if (fi->fib_prefsrc) { | |
924 | struct hlist_head *head; | |
925 | ||
926 | head = &fib_info_laddrhash[fib_laddr_hashfn(fi->fib_prefsrc)]; | |
927 | hlist_add_head(&fi->fib_lhash, head); | |
928 | } | |
929 | change_nexthops(fi) { | |
930 | struct hlist_head *head; | |
931 | unsigned int hash; | |
932 | ||
71fceff0 | 933 | if (!nexthop_nh->nh_dev) |
1da177e4 | 934 | continue; |
71fceff0 | 935 | hash = fib_devindex_hashfn(nexthop_nh->nh_dev->ifindex); |
1da177e4 | 936 | head = &fib_info_devhash[hash]; |
71fceff0 | 937 | hlist_add_head(&nexthop_nh->nh_hash, head); |
1da177e4 | 938 | } endfor_nexthops(fi) |
832b4c5e | 939 | spin_unlock_bh(&fib_info_lock); |
1da177e4 LT |
940 | return fi; |
941 | ||
942 | err_inval: | |
943 | err = -EINVAL; | |
944 | ||
945 | failure: | |
e905a9ed | 946 | if (fi) { |
1da177e4 LT |
947 | fi->fib_dead = 1; |
948 | free_fib_info(fi); | |
949 | } | |
4e902c57 TG |
950 | |
951 | return ERR_PTR(err); | |
1da177e4 LT |
952 | } |
953 | ||
be403ea1 | 954 | int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event, |
37e826c5 | 955 | u32 tb_id, u8 type, __be32 dst, int dst_len, u8 tos, |
be403ea1 | 956 | struct fib_info *fi, unsigned int flags) |
1da177e4 | 957 | { |
be403ea1 | 958 | struct nlmsghdr *nlh; |
1da177e4 | 959 | struct rtmsg *rtm; |
1da177e4 | 960 | |
be403ea1 TG |
961 | nlh = nlmsg_put(skb, pid, seq, event, sizeof(*rtm), flags); |
962 | if (nlh == NULL) | |
26932566 | 963 | return -EMSGSIZE; |
be403ea1 TG |
964 | |
965 | rtm = nlmsg_data(nlh); | |
1da177e4 LT |
966 | rtm->rtm_family = AF_INET; |
967 | rtm->rtm_dst_len = dst_len; | |
968 | rtm->rtm_src_len = 0; | |
969 | rtm->rtm_tos = tos; | |
709772e6 KPO |
970 | if (tb_id < 256) |
971 | rtm->rtm_table = tb_id; | |
972 | else | |
973 | rtm->rtm_table = RT_TABLE_COMPAT; | |
f3756b79 DM |
974 | if (nla_put_u32(skb, RTA_TABLE, tb_id)) |
975 | goto nla_put_failure; | |
1da177e4 LT |
976 | rtm->rtm_type = type; |
977 | rtm->rtm_flags = fi->fib_flags; | |
37e826c5 | 978 | rtm->rtm_scope = fi->fib_scope; |
1da177e4 | 979 | rtm->rtm_protocol = fi->fib_protocol; |
be403ea1 | 980 | |
f3756b79 DM |
981 | if (rtm->rtm_dst_len && |
982 | nla_put_be32(skb, RTA_DST, dst)) | |
983 | goto nla_put_failure; | |
984 | if (fi->fib_priority && | |
985 | nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority)) | |
986 | goto nla_put_failure; | |
1da177e4 | 987 | if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0) |
be403ea1 TG |
988 | goto nla_put_failure; |
989 | ||
f3756b79 DM |
990 | if (fi->fib_prefsrc && |
991 | nla_put_be32(skb, RTA_PREFSRC, fi->fib_prefsrc)) | |
992 | goto nla_put_failure; | |
1da177e4 | 993 | if (fi->fib_nhs == 1) { |
f3756b79 DM |
994 | if (fi->fib_nh->nh_gw && |
995 | nla_put_be32(skb, RTA_GATEWAY, fi->fib_nh->nh_gw)) | |
996 | goto nla_put_failure; | |
997 | if (fi->fib_nh->nh_oif && | |
998 | nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif)) | |
999 | goto nla_put_failure; | |
c7066f70 | 1000 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
1001 | if (fi->fib_nh[0].nh_tclassid && |
1002 | nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid)) | |
1003 | goto nla_put_failure; | |
8265abc0 | 1004 | #endif |
1da177e4 LT |
1005 | } |
1006 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
1007 | if (fi->fib_nhs > 1) { | |
be403ea1 TG |
1008 | struct rtnexthop *rtnh; |
1009 | struct nlattr *mp; | |
1010 | ||
1011 | mp = nla_nest_start(skb, RTA_MULTIPATH); | |
1012 | if (mp == NULL) | |
1013 | goto nla_put_failure; | |
1da177e4 LT |
1014 | |
1015 | for_nexthops(fi) { | |
be403ea1 TG |
1016 | rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); |
1017 | if (rtnh == NULL) | |
1018 | goto nla_put_failure; | |
1019 | ||
1020 | rtnh->rtnh_flags = nh->nh_flags & 0xFF; | |
1021 | rtnh->rtnh_hops = nh->nh_weight - 1; | |
1022 | rtnh->rtnh_ifindex = nh->nh_oif; | |
1023 | ||
f3756b79 DM |
1024 | if (nh->nh_gw && |
1025 | nla_put_be32(skb, RTA_GATEWAY, nh->nh_gw)) | |
1026 | goto nla_put_failure; | |
c7066f70 | 1027 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
1028 | if (nh->nh_tclassid && |
1029 | nla_put_u32(skb, RTA_FLOW, nh->nh_tclassid)) | |
1030 | goto nla_put_failure; | |
8265abc0 | 1031 | #endif |
be403ea1 TG |
1032 | /* length of rtnetlink header + attributes */ |
1033 | rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *) rtnh; | |
1da177e4 | 1034 | } endfor_nexthops(fi); |
be403ea1 TG |
1035 | |
1036 | nla_nest_end(skb, mp); | |
1da177e4 LT |
1037 | } |
1038 | #endif | |
be403ea1 | 1039 | return nlmsg_end(skb, nlh); |
1da177e4 | 1040 | |
be403ea1 | 1041 | nla_put_failure: |
26932566 PM |
1042 | nlmsg_cancel(skb, nlh); |
1043 | return -EMSGSIZE; | |
1da177e4 LT |
1044 | } |
1045 | ||
1da177e4 | 1046 | /* |
6a31d2a9 ED |
1047 | * Update FIB if: |
1048 | * - local address disappeared -> we must delete all the entries | |
1049 | * referring to it. | |
1050 | * - device went down -> we must shutdown all nexthops going via it. | |
1da177e4 | 1051 | */ |
4814bdbd | 1052 | int fib_sync_down_addr(struct net *net, __be32 local) |
1da177e4 LT |
1053 | { |
1054 | int ret = 0; | |
85326fa5 DL |
1055 | unsigned int hash = fib_laddr_hashfn(local); |
1056 | struct hlist_head *head = &fib_info_laddrhash[hash]; | |
1057 | struct hlist_node *node; | |
1058 | struct fib_info *fi; | |
1da177e4 | 1059 | |
85326fa5 DL |
1060 | if (fib_info_laddrhash == NULL || local == 0) |
1061 | return 0; | |
1da177e4 | 1062 | |
85326fa5 | 1063 | hlist_for_each_entry(fi, node, head, fib_lhash) { |
09ad9bc7 | 1064 | if (!net_eq(fi->fib_net, net)) |
4814bdbd | 1065 | continue; |
85326fa5 DL |
1066 | if (fi->fib_prefsrc == local) { |
1067 | fi->fib_flags |= RTNH_F_DEAD; | |
1068 | ret++; | |
1da177e4 LT |
1069 | } |
1070 | } | |
85326fa5 DL |
1071 | return ret; |
1072 | } | |
1073 | ||
1074 | int fib_sync_down_dev(struct net_device *dev, int force) | |
1075 | { | |
1076 | int ret = 0; | |
1077 | int scope = RT_SCOPE_NOWHERE; | |
1078 | struct fib_info *prev_fi = NULL; | |
1079 | unsigned int hash = fib_devindex_hashfn(dev->ifindex); | |
1080 | struct hlist_head *head = &fib_info_devhash[hash]; | |
1081 | struct hlist_node *node; | |
1082 | struct fib_nh *nh; | |
1da177e4 | 1083 | |
85326fa5 DL |
1084 | if (force) |
1085 | scope = -1; | |
1da177e4 | 1086 | |
85326fa5 DL |
1087 | hlist_for_each_entry(nh, node, head, nh_hash) { |
1088 | struct fib_info *fi = nh->nh_parent; | |
1089 | int dead; | |
1da177e4 | 1090 | |
85326fa5 DL |
1091 | BUG_ON(!fi->fib_nhs); |
1092 | if (nh->nh_dev != dev || fi == prev_fi) | |
1093 | continue; | |
1094 | prev_fi = fi; | |
1095 | dead = 0; | |
1096 | change_nexthops(fi) { | |
6a31d2a9 | 1097 | if (nexthop_nh->nh_flags & RTNH_F_DEAD) |
85326fa5 | 1098 | dead++; |
71fceff0 DM |
1099 | else if (nexthop_nh->nh_dev == dev && |
1100 | nexthop_nh->nh_scope != scope) { | |
1101 | nexthop_nh->nh_flags |= RTNH_F_DEAD; | |
1da177e4 | 1102 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
85326fa5 | 1103 | spin_lock_bh(&fib_multipath_lock); |
71fceff0 DM |
1104 | fi->fib_power -= nexthop_nh->nh_power; |
1105 | nexthop_nh->nh_power = 0; | |
85326fa5 | 1106 | spin_unlock_bh(&fib_multipath_lock); |
1da177e4 | 1107 | #endif |
85326fa5 DL |
1108 | dead++; |
1109 | } | |
1da177e4 | 1110 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
71fceff0 | 1111 | if (force > 1 && nexthop_nh->nh_dev == dev) { |
85326fa5 DL |
1112 | dead = fi->fib_nhs; |
1113 | break; | |
1da177e4 | 1114 | } |
85326fa5 DL |
1115 | #endif |
1116 | } endfor_nexthops(fi) | |
1117 | if (dead == fi->fib_nhs) { | |
1118 | fi->fib_flags |= RTNH_F_DEAD; | |
1119 | ret++; | |
1da177e4 LT |
1120 | } |
1121 | } | |
1122 | ||
1123 | return ret; | |
1124 | } | |
1125 | ||
0c838ff1 DM |
1126 | /* Must be invoked inside of an RCU protected region. */ |
1127 | void fib_select_default(struct fib_result *res) | |
1128 | { | |
1129 | struct fib_info *fi = NULL, *last_resort = NULL; | |
1130 | struct list_head *fa_head = res->fa_head; | |
1131 | struct fib_table *tb = res->table; | |
1132 | int order = -1, last_idx = -1; | |
1133 | struct fib_alias *fa; | |
1134 | ||
1135 | list_for_each_entry_rcu(fa, fa_head, fa_list) { | |
1136 | struct fib_info *next_fi = fa->fa_info; | |
1137 | ||
37e826c5 | 1138 | if (next_fi->fib_scope != res->scope || |
0c838ff1 DM |
1139 | fa->fa_type != RTN_UNICAST) |
1140 | continue; | |
1141 | ||
1142 | if (next_fi->fib_priority > res->fi->fib_priority) | |
1143 | break; | |
1144 | if (!next_fi->fib_nh[0].nh_gw || | |
1145 | next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK) | |
1146 | continue; | |
1147 | ||
1148 | fib_alias_accessed(fa); | |
1149 | ||
1150 | if (fi == NULL) { | |
1151 | if (next_fi != res->fi) | |
1152 | break; | |
1153 | } else if (!fib_detect_death(fi, order, &last_resort, | |
1154 | &last_idx, tb->tb_default)) { | |
1155 | fib_result_assign(res, fi); | |
1156 | tb->tb_default = order; | |
1157 | goto out; | |
1158 | } | |
1159 | fi = next_fi; | |
1160 | order++; | |
1161 | } | |
1162 | ||
1163 | if (order <= 0 || fi == NULL) { | |
1164 | tb->tb_default = -1; | |
1165 | goto out; | |
1166 | } | |
1167 | ||
1168 | if (!fib_detect_death(fi, order, &last_resort, &last_idx, | |
1169 | tb->tb_default)) { | |
1170 | fib_result_assign(res, fi); | |
1171 | tb->tb_default = order; | |
1172 | goto out; | |
1173 | } | |
1174 | ||
1175 | if (last_idx >= 0) | |
1176 | fib_result_assign(res, last_resort); | |
1177 | tb->tb_default = last_idx; | |
1178 | out: | |
31d40937 | 1179 | return; |
0c838ff1 DM |
1180 | } |
1181 | ||
1da177e4 LT |
1182 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
1183 | ||
1184 | /* | |
6a31d2a9 ED |
1185 | * Dead device goes up. We wake up dead nexthops. |
1186 | * It takes sense only on multipath routes. | |
1da177e4 | 1187 | */ |
1da177e4 LT |
1188 | int fib_sync_up(struct net_device *dev) |
1189 | { | |
1190 | struct fib_info *prev_fi; | |
1191 | unsigned int hash; | |
1192 | struct hlist_head *head; | |
1193 | struct hlist_node *node; | |
1194 | struct fib_nh *nh; | |
1195 | int ret; | |
1196 | ||
6a31d2a9 | 1197 | if (!(dev->flags & IFF_UP)) |
1da177e4 LT |
1198 | return 0; |
1199 | ||
1200 | prev_fi = NULL; | |
1201 | hash = fib_devindex_hashfn(dev->ifindex); | |
1202 | head = &fib_info_devhash[hash]; | |
1203 | ret = 0; | |
1204 | ||
1205 | hlist_for_each_entry(nh, node, head, nh_hash) { | |
1206 | struct fib_info *fi = nh->nh_parent; | |
1207 | int alive; | |
1208 | ||
1209 | BUG_ON(!fi->fib_nhs); | |
1210 | if (nh->nh_dev != dev || fi == prev_fi) | |
1211 | continue; | |
1212 | ||
1213 | prev_fi = fi; | |
1214 | alive = 0; | |
1215 | change_nexthops(fi) { | |
6a31d2a9 | 1216 | if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { |
1da177e4 LT |
1217 | alive++; |
1218 | continue; | |
1219 | } | |
71fceff0 | 1220 | if (nexthop_nh->nh_dev == NULL || |
6a31d2a9 | 1221 | !(nexthop_nh->nh_dev->flags & IFF_UP)) |
1da177e4 | 1222 | continue; |
71fceff0 DM |
1223 | if (nexthop_nh->nh_dev != dev || |
1224 | !__in_dev_get_rtnl(dev)) | |
1da177e4 LT |
1225 | continue; |
1226 | alive++; | |
1227 | spin_lock_bh(&fib_multipath_lock); | |
71fceff0 DM |
1228 | nexthop_nh->nh_power = 0; |
1229 | nexthop_nh->nh_flags &= ~RTNH_F_DEAD; | |
1da177e4 LT |
1230 | spin_unlock_bh(&fib_multipath_lock); |
1231 | } endfor_nexthops(fi) | |
1232 | ||
1233 | if (alive > 0) { | |
1234 | fi->fib_flags &= ~RTNH_F_DEAD; | |
1235 | ret++; | |
1236 | } | |
1237 | } | |
1238 | ||
1239 | return ret; | |
1240 | } | |
1241 | ||
1242 | /* | |
6a31d2a9 ED |
1243 | * The algorithm is suboptimal, but it provides really |
1244 | * fair weighted route distribution. | |
1da177e4 | 1245 | */ |
1b7fe593 | 1246 | void fib_select_multipath(struct fib_result *res) |
1da177e4 LT |
1247 | { |
1248 | struct fib_info *fi = res->fi; | |
1249 | int w; | |
1250 | ||
1251 | spin_lock_bh(&fib_multipath_lock); | |
1252 | if (fi->fib_power <= 0) { | |
1253 | int power = 0; | |
1254 | change_nexthops(fi) { | |
6a31d2a9 | 1255 | if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { |
71fceff0 DM |
1256 | power += nexthop_nh->nh_weight; |
1257 | nexthop_nh->nh_power = nexthop_nh->nh_weight; | |
1da177e4 LT |
1258 | } |
1259 | } endfor_nexthops(fi); | |
1260 | fi->fib_power = power; | |
1261 | if (power <= 0) { | |
1262 | spin_unlock_bh(&fib_multipath_lock); | |
1263 | /* Race condition: route has just become dead. */ | |
1264 | res->nh_sel = 0; | |
1265 | return; | |
1266 | } | |
1267 | } | |
1268 | ||
1269 | ||
1270 | /* w should be random number [0..fi->fib_power-1], | |
6a31d2a9 | 1271 | * it is pretty bad approximation. |
1da177e4 LT |
1272 | */ |
1273 | ||
1274 | w = jiffies % fi->fib_power; | |
1275 | ||
1276 | change_nexthops(fi) { | |
6a31d2a9 | 1277 | if (!(nexthop_nh->nh_flags & RTNH_F_DEAD) && |
71fceff0 | 1278 | nexthop_nh->nh_power) { |
6a31d2a9 ED |
1279 | w -= nexthop_nh->nh_power; |
1280 | if (w <= 0) { | |
71fceff0 | 1281 | nexthop_nh->nh_power--; |
1da177e4 LT |
1282 | fi->fib_power--; |
1283 | res->nh_sel = nhsel; | |
1284 | spin_unlock_bh(&fib_multipath_lock); | |
1285 | return; | |
1286 | } | |
1287 | } | |
1288 | } endfor_nexthops(fi); | |
1289 | ||
1290 | /* Race condition: route has just become dead. */ | |
1291 | res->nh_sel = 0; | |
1292 | spin_unlock_bh(&fib_multipath_lock); | |
1293 | } | |
1294 | #endif |