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 | ||
c5038a83 DM |
143 | static void rt_fibinfo_free(struct rtable __rcu **rtp) |
144 | { | |
145 | struct rtable *rt = rcu_dereference_protected(*rtp, 1); | |
146 | ||
147 | if (!rt) | |
148 | return; | |
149 | ||
150 | /* Not even needed : RCU_INIT_POINTER(*rtp, NULL); | |
151 | * because we waited an RCU grace period before calling | |
152 | * free_fib_info_rcu() | |
153 | */ | |
154 | ||
155 | dst_free(&rt->dst); | |
156 | } | |
157 | ||
4895c771 DM |
158 | static void free_nh_exceptions(struct fib_nh *nh) |
159 | { | |
160 | struct fnhe_hash_bucket *hash = nh->nh_exceptions; | |
161 | int i; | |
162 | ||
163 | for (i = 0; i < FNHE_HASH_SIZE; i++) { | |
164 | struct fib_nh_exception *fnhe; | |
165 | ||
5abf7f7e | 166 | fnhe = rcu_dereference_protected(hash[i].chain, 1); |
4895c771 DM |
167 | while (fnhe) { |
168 | struct fib_nh_exception *next; | |
169 | ||
5abf7f7e | 170 | next = rcu_dereference_protected(fnhe->fnhe_next, 1); |
c5038a83 | 171 | |
2ffae99d TT |
172 | rt_fibinfo_free(&fnhe->fnhe_rth_input); |
173 | rt_fibinfo_free(&fnhe->fnhe_rth_output); | |
c5038a83 | 174 | |
4895c771 DM |
175 | kfree(fnhe); |
176 | ||
177 | fnhe = next; | |
178 | } | |
179 | } | |
180 | kfree(hash); | |
181 | } | |
182 | ||
c5038a83 | 183 | static void rt_fibinfo_free_cpus(struct rtable __rcu * __percpu *rtp) |
d26b3a7c ED |
184 | { |
185 | int cpu; | |
186 | ||
187 | if (!rtp) | |
188 | return; | |
189 | ||
190 | for_each_possible_cpu(cpu) { | |
191 | struct rtable *rt; | |
192 | ||
193 | rt = rcu_dereference_protected(*per_cpu_ptr(rtp, cpu), 1); | |
194 | if (rt) | |
195 | dst_free(&rt->dst); | |
196 | } | |
197 | free_percpu(rtp); | |
198 | } | |
199 | ||
1da177e4 | 200 | /* Release a nexthop info record */ |
19c1ea14 YZ |
201 | static void free_fib_info_rcu(struct rcu_head *head) |
202 | { | |
203 | struct fib_info *fi = container_of(head, struct fib_info, rcu); | |
204 | ||
e49cc0da YZ |
205 | change_nexthops(fi) { |
206 | if (nexthop_nh->nh_dev) | |
207 | dev_put(nexthop_nh->nh_dev); | |
4895c771 DM |
208 | if (nexthop_nh->nh_exceptions) |
209 | free_nh_exceptions(nexthop_nh); | |
c5038a83 DM |
210 | rt_fibinfo_free_cpus(nexthop_nh->nh_pcpu_rth_output); |
211 | rt_fibinfo_free(&nexthop_nh->nh_rth_input); | |
e49cc0da YZ |
212 | } endfor_nexthops(fi); |
213 | ||
214 | release_net(fi->fib_net); | |
19c1ea14 YZ |
215 | if (fi->fib_metrics != (u32 *) dst_default_metrics) |
216 | kfree(fi->fib_metrics); | |
217 | kfree(fi); | |
218 | } | |
1da177e4 LT |
219 | |
220 | void free_fib_info(struct fib_info *fi) | |
221 | { | |
222 | if (fi->fib_dead == 0) { | |
058bd4d2 | 223 | pr_warn("Freeing alive fib_info %p\n", fi); |
1da177e4 LT |
224 | return; |
225 | } | |
1da177e4 | 226 | fib_info_cnt--; |
7a9bc9b8 DM |
227 | #ifdef CONFIG_IP_ROUTE_CLASSID |
228 | change_nexthops(fi) { | |
229 | if (nexthop_nh->nh_tclassid) | |
f4530fa5 | 230 | fi->fib_net->ipv4.fib_num_tclassid_users--; |
7a9bc9b8 DM |
231 | } endfor_nexthops(fi); |
232 | #endif | |
19c1ea14 | 233 | call_rcu(&fi->rcu, free_fib_info_rcu); |
1da177e4 LT |
234 | } |
235 | ||
236 | void fib_release_info(struct fib_info *fi) | |
237 | { | |
832b4c5e | 238 | spin_lock_bh(&fib_info_lock); |
1da177e4 LT |
239 | if (fi && --fi->fib_treeref == 0) { |
240 | hlist_del(&fi->fib_hash); | |
241 | if (fi->fib_prefsrc) | |
242 | hlist_del(&fi->fib_lhash); | |
243 | change_nexthops(fi) { | |
71fceff0 | 244 | if (!nexthop_nh->nh_dev) |
1da177e4 | 245 | continue; |
71fceff0 | 246 | hlist_del(&nexthop_nh->nh_hash); |
1da177e4 LT |
247 | } endfor_nexthops(fi) |
248 | fi->fib_dead = 1; | |
249 | fib_info_put(fi); | |
250 | } | |
832b4c5e | 251 | spin_unlock_bh(&fib_info_lock); |
1da177e4 LT |
252 | } |
253 | ||
6a31d2a9 | 254 | static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi) |
1da177e4 LT |
255 | { |
256 | const struct fib_nh *onh = ofi->fib_nh; | |
257 | ||
258 | for_nexthops(fi) { | |
259 | if (nh->nh_oif != onh->nh_oif || | |
260 | nh->nh_gw != onh->nh_gw || | |
261 | nh->nh_scope != onh->nh_scope || | |
262 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
263 | nh->nh_weight != onh->nh_weight || | |
264 | #endif | |
c7066f70 | 265 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
266 | nh->nh_tclassid != onh->nh_tclassid || |
267 | #endif | |
6a31d2a9 | 268 | ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD)) |
1da177e4 LT |
269 | return -1; |
270 | onh++; | |
271 | } endfor_nexthops(fi); | |
272 | return 0; | |
273 | } | |
274 | ||
88ebc72f DM |
275 | static inline unsigned int fib_devindex_hashfn(unsigned int val) |
276 | { | |
277 | unsigned int mask = DEVINDEX_HASHSIZE - 1; | |
278 | ||
279 | return (val ^ | |
280 | (val >> DEVINDEX_HASHBITS) ^ | |
281 | (val >> (DEVINDEX_HASHBITS * 2))) & mask; | |
282 | } | |
283 | ||
1da177e4 LT |
284 | static inline unsigned int fib_info_hashfn(const struct fib_info *fi) |
285 | { | |
123b9731 | 286 | unsigned int mask = (fib_info_hash_size - 1); |
1da177e4 LT |
287 | unsigned int val = fi->fib_nhs; |
288 | ||
37e826c5 | 289 | val ^= (fi->fib_protocol << 8) | fi->fib_scope; |
81f7bf6c | 290 | val ^= (__force u32)fi->fib_prefsrc; |
1da177e4 | 291 | val ^= fi->fib_priority; |
88ebc72f DM |
292 | for_nexthops(fi) { |
293 | val ^= fib_devindex_hashfn(nh->nh_oif); | |
294 | } endfor_nexthops(fi) | |
1da177e4 LT |
295 | |
296 | return (val ^ (val >> 7) ^ (val >> 12)) & mask; | |
297 | } | |
298 | ||
299 | static struct fib_info *fib_find_info(const struct fib_info *nfi) | |
300 | { | |
301 | struct hlist_head *head; | |
1da177e4 LT |
302 | struct fib_info *fi; |
303 | unsigned int hash; | |
304 | ||
305 | hash = fib_info_hashfn(nfi); | |
306 | head = &fib_info_hash[hash]; | |
307 | ||
b67bfe0d | 308 | hlist_for_each_entry(fi, head, fib_hash) { |
09ad9bc7 | 309 | if (!net_eq(fi->fib_net, nfi->fib_net)) |
4814bdbd | 310 | continue; |
1da177e4 LT |
311 | if (fi->fib_nhs != nfi->fib_nhs) |
312 | continue; | |
313 | if (nfi->fib_protocol == fi->fib_protocol && | |
37e826c5 | 314 | nfi->fib_scope == fi->fib_scope && |
1da177e4 LT |
315 | nfi->fib_prefsrc == fi->fib_prefsrc && |
316 | nfi->fib_priority == fi->fib_priority && | |
f4ef85bb | 317 | nfi->fib_type == fi->fib_type && |
1da177e4 | 318 | memcmp(nfi->fib_metrics, fi->fib_metrics, |
fcd13f42 | 319 | sizeof(u32) * RTAX_MAX) == 0 && |
6a31d2a9 | 320 | ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 && |
1da177e4 LT |
321 | (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0)) |
322 | return fi; | |
323 | } | |
324 | ||
325 | return NULL; | |
326 | } | |
327 | ||
1da177e4 | 328 | /* Check, that the gateway is already configured. |
6a31d2a9 | 329 | * Used only by redirect accept routine. |
1da177e4 | 330 | */ |
d878e72e | 331 | int ip_fib_check_default(__be32 gw, struct net_device *dev) |
1da177e4 LT |
332 | { |
333 | struct hlist_head *head; | |
1da177e4 LT |
334 | struct fib_nh *nh; |
335 | unsigned int hash; | |
336 | ||
832b4c5e | 337 | spin_lock(&fib_info_lock); |
1da177e4 LT |
338 | |
339 | hash = fib_devindex_hashfn(dev->ifindex); | |
340 | head = &fib_info_devhash[hash]; | |
b67bfe0d | 341 | hlist_for_each_entry(nh, head, nh_hash) { |
1da177e4 LT |
342 | if (nh->nh_dev == dev && |
343 | nh->nh_gw == gw && | |
6a31d2a9 | 344 | !(nh->nh_flags & RTNH_F_DEAD)) { |
832b4c5e | 345 | spin_unlock(&fib_info_lock); |
1da177e4 LT |
346 | return 0; |
347 | } | |
348 | } | |
349 | ||
832b4c5e | 350 | spin_unlock(&fib_info_lock); |
1da177e4 LT |
351 | |
352 | return -1; | |
353 | } | |
354 | ||
339bf98f TG |
355 | static inline size_t fib_nlmsg_size(struct fib_info *fi) |
356 | { | |
357 | size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg)) | |
358 | + nla_total_size(4) /* RTA_TABLE */ | |
359 | + nla_total_size(4) /* RTA_DST */ | |
360 | + nla_total_size(4) /* RTA_PRIORITY */ | |
361 | + nla_total_size(4); /* RTA_PREFSRC */ | |
362 | ||
363 | /* space for nested metrics */ | |
364 | payload += nla_total_size((RTAX_MAX * nla_total_size(4))); | |
365 | ||
366 | if (fi->fib_nhs) { | |
367 | /* Also handles the special case fib_nhs == 1 */ | |
368 | ||
369 | /* each nexthop is packed in an attribute */ | |
370 | size_t nhsize = nla_total_size(sizeof(struct rtnexthop)); | |
371 | ||
372 | /* may contain flow and gateway attribute */ | |
373 | nhsize += 2 * nla_total_size(4); | |
374 | ||
375 | /* all nexthops are packed in a nested attribute */ | |
376 | payload += nla_total_size(fi->fib_nhs * nhsize); | |
377 | } | |
378 | ||
379 | return payload; | |
380 | } | |
381 | ||
81f7bf6c | 382 | void rtmsg_fib(int event, __be32 key, struct fib_alias *fa, |
9877b253 | 383 | int dst_len, u32 tb_id, const struct nl_info *info, |
b8f55831 | 384 | unsigned int nlm_flags) |
1da177e4 LT |
385 | { |
386 | struct sk_buff *skb; | |
4e902c57 | 387 | u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; |
f21c7bc5 | 388 | int err = -ENOBUFS; |
1da177e4 | 389 | |
339bf98f | 390 | skb = nlmsg_new(fib_nlmsg_size(fa->fa_info), GFP_KERNEL); |
f21c7bc5 TG |
391 | if (skb == NULL) |
392 | goto errout; | |
1da177e4 | 393 | |
15e47304 | 394 | err = fib_dump_info(skb, info->portid, seq, event, tb_id, |
37e826c5 | 395 | fa->fa_type, key, dst_len, |
b8f55831 | 396 | fa->fa_tos, fa->fa_info, nlm_flags); |
26932566 PM |
397 | if (err < 0) { |
398 | /* -EMSGSIZE implies BUG in fib_nlmsg_size() */ | |
399 | WARN_ON(err == -EMSGSIZE); | |
400 | kfree_skb(skb); | |
401 | goto errout; | |
402 | } | |
15e47304 | 403 | rtnl_notify(skb, info->nl_net, info->portid, RTNLGRP_IPV4_ROUTE, |
1ce85fe4 PNA |
404 | info->nlh, GFP_KERNEL); |
405 | return; | |
f21c7bc5 TG |
406 | errout: |
407 | if (err < 0) | |
4d1169c1 | 408 | rtnl_set_sk_err(info->nl_net, RTNLGRP_IPV4_ROUTE, err); |
1da177e4 LT |
409 | } |
410 | ||
411 | /* Return the first fib alias matching TOS with | |
412 | * priority less than or equal to PRIO. | |
413 | */ | |
414 | struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio) | |
415 | { | |
416 | if (fah) { | |
417 | struct fib_alias *fa; | |
418 | list_for_each_entry(fa, fah, fa_list) { | |
419 | if (fa->fa_tos > tos) | |
420 | continue; | |
421 | if (fa->fa_info->fib_priority >= prio || | |
422 | fa->fa_tos < tos) | |
423 | return fa; | |
424 | } | |
425 | } | |
426 | return NULL; | |
427 | } | |
428 | ||
c9cb6b6e SH |
429 | static int fib_detect_death(struct fib_info *fi, int order, |
430 | struct fib_info **last_resort, int *last_idx, | |
431 | int dflt) | |
1da177e4 LT |
432 | { |
433 | struct neighbour *n; | |
434 | int state = NUD_NONE; | |
435 | ||
436 | n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev); | |
437 | if (n) { | |
438 | state = n->nud_state; | |
439 | neigh_release(n); | |
440 | } | |
d9319100 | 441 | if (state == NUD_REACHABLE) |
1da177e4 | 442 | return 0; |
6a31d2a9 | 443 | if ((state & NUD_VALID) && order != dflt) |
1da177e4 | 444 | return 0; |
6a31d2a9 ED |
445 | if ((state & NUD_VALID) || |
446 | (*last_idx < 0 && order > dflt)) { | |
1da177e4 LT |
447 | *last_resort = fi; |
448 | *last_idx = order; | |
449 | } | |
450 | return 1; | |
451 | } | |
452 | ||
453 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
454 | ||
4e902c57 | 455 | static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining) |
1da177e4 LT |
456 | { |
457 | int nhs = 0; | |
1da177e4 | 458 | |
4e902c57 | 459 | while (rtnh_ok(rtnh, remaining)) { |
1da177e4 | 460 | nhs++; |
4e902c57 TG |
461 | rtnh = rtnh_next(rtnh, &remaining); |
462 | } | |
463 | ||
464 | /* leftover implies invalid nexthop configuration, discard it */ | |
465 | return remaining > 0 ? 0 : nhs; | |
1da177e4 LT |
466 | } |
467 | ||
4e902c57 TG |
468 | static int fib_get_nhs(struct fib_info *fi, struct rtnexthop *rtnh, |
469 | int remaining, struct fib_config *cfg) | |
1da177e4 | 470 | { |
1da177e4 | 471 | change_nexthops(fi) { |
4e902c57 TG |
472 | int attrlen; |
473 | ||
474 | if (!rtnh_ok(rtnh, remaining)) | |
1da177e4 | 475 | return -EINVAL; |
4e902c57 | 476 | |
71fceff0 DM |
477 | nexthop_nh->nh_flags = |
478 | (cfg->fc_flags & ~0xFF) | rtnh->rtnh_flags; | |
479 | nexthop_nh->nh_oif = rtnh->rtnh_ifindex; | |
480 | nexthop_nh->nh_weight = rtnh->rtnh_hops + 1; | |
4e902c57 TG |
481 | |
482 | attrlen = rtnh_attrlen(rtnh); | |
483 | if (attrlen > 0) { | |
484 | struct nlattr *nla, *attrs = rtnh_attrs(rtnh); | |
485 | ||
486 | nla = nla_find(attrs, attrlen, RTA_GATEWAY); | |
71fceff0 | 487 | nexthop_nh->nh_gw = nla ? nla_get_be32(nla) : 0; |
c7066f70 | 488 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 | 489 | nla = nla_find(attrs, attrlen, RTA_FLOW); |
71fceff0 | 490 | nexthop_nh->nh_tclassid = nla ? nla_get_u32(nla) : 0; |
7a9bc9b8 | 491 | if (nexthop_nh->nh_tclassid) |
f4530fa5 | 492 | fi->fib_net->ipv4.fib_num_tclassid_users++; |
1da177e4 LT |
493 | #endif |
494 | } | |
4e902c57 TG |
495 | |
496 | rtnh = rtnh_next(rtnh, &remaining); | |
1da177e4 | 497 | } endfor_nexthops(fi); |
4e902c57 | 498 | |
1da177e4 LT |
499 | return 0; |
500 | } | |
501 | ||
502 | #endif | |
503 | ||
4e902c57 | 504 | int fib_nh_match(struct fib_config *cfg, struct fib_info *fi) |
1da177e4 LT |
505 | { |
506 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
4e902c57 TG |
507 | struct rtnexthop *rtnh; |
508 | int remaining; | |
1da177e4 LT |
509 | #endif |
510 | ||
4e902c57 | 511 | if (cfg->fc_priority && cfg->fc_priority != fi->fib_priority) |
1da177e4 LT |
512 | return 1; |
513 | ||
4e902c57 TG |
514 | if (cfg->fc_oif || cfg->fc_gw) { |
515 | if ((!cfg->fc_oif || cfg->fc_oif == fi->fib_nh->nh_oif) && | |
516 | (!cfg->fc_gw || cfg->fc_gw == fi->fib_nh->nh_gw)) | |
1da177e4 LT |
517 | return 0; |
518 | return 1; | |
519 | } | |
520 | ||
521 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
4e902c57 | 522 | if (cfg->fc_mp == NULL) |
1da177e4 | 523 | return 0; |
4e902c57 TG |
524 | |
525 | rtnh = cfg->fc_mp; | |
526 | remaining = cfg->fc_mp_len; | |
e905a9ed | 527 | |
1da177e4 | 528 | for_nexthops(fi) { |
4e902c57 | 529 | int attrlen; |
1da177e4 | 530 | |
4e902c57 | 531 | if (!rtnh_ok(rtnh, remaining)) |
1da177e4 | 532 | return -EINVAL; |
4e902c57 TG |
533 | |
534 | if (rtnh->rtnh_ifindex && rtnh->rtnh_ifindex != nh->nh_oif) | |
1da177e4 | 535 | return 1; |
4e902c57 TG |
536 | |
537 | attrlen = rtnh_attrlen(rtnh); | |
538 | if (attrlen < 0) { | |
539 | struct nlattr *nla, *attrs = rtnh_attrs(rtnh); | |
540 | ||
541 | nla = nla_find(attrs, attrlen, RTA_GATEWAY); | |
17fb2c64 | 542 | if (nla && nla_get_be32(nla) != nh->nh_gw) |
1da177e4 | 543 | return 1; |
c7066f70 | 544 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 TG |
545 | nla = nla_find(attrs, attrlen, RTA_FLOW); |
546 | if (nla && nla_get_u32(nla) != nh->nh_tclassid) | |
1da177e4 LT |
547 | return 1; |
548 | #endif | |
549 | } | |
4e902c57 TG |
550 | |
551 | rtnh = rtnh_next(rtnh, &remaining); | |
1da177e4 LT |
552 | } endfor_nexthops(fi); |
553 | #endif | |
554 | return 0; | |
555 | } | |
556 | ||
557 | ||
558 | /* | |
6a31d2a9 ED |
559 | * Picture |
560 | * ------- | |
561 | * | |
562 | * Semantics of nexthop is very messy by historical reasons. | |
563 | * We have to take into account, that: | |
564 | * a) gateway can be actually local interface address, | |
565 | * so that gatewayed route is direct. | |
566 | * b) gateway must be on-link address, possibly | |
567 | * described not by an ifaddr, but also by a direct route. | |
568 | * c) If both gateway and interface are specified, they should not | |
569 | * contradict. | |
570 | * d) If we use tunnel routes, gateway could be not on-link. | |
571 | * | |
572 | * Attempt to reconcile all of these (alas, self-contradictory) conditions | |
573 | * results in pretty ugly and hairy code with obscure logic. | |
574 | * | |
575 | * I chose to generalized it instead, so that the size | |
576 | * of code does not increase practically, but it becomes | |
577 | * much more general. | |
578 | * Every prefix is assigned a "scope" value: "host" is local address, | |
579 | * "link" is direct route, | |
580 | * [ ... "site" ... "interior" ... ] | |
581 | * and "universe" is true gateway route with global meaning. | |
582 | * | |
583 | * Every prefix refers to a set of "nexthop"s (gw, oif), | |
584 | * where gw must have narrower scope. This recursion stops | |
585 | * when gw has LOCAL scope or if "nexthop" is declared ONLINK, | |
586 | * which means that gw is forced to be on link. | |
587 | * | |
588 | * Code is still hairy, but now it is apparently logically | |
589 | * consistent and very flexible. F.e. as by-product it allows | |
590 | * to co-exists in peace independent exterior and interior | |
591 | * routing processes. | |
592 | * | |
593 | * Normally it looks as following. | |
594 | * | |
595 | * {universe prefix} -> (gw, oif) [scope link] | |
596 | * | | |
597 | * |-> {link prefix} -> (gw, oif) [scope local] | |
598 | * | | |
599 | * |-> {local prefix} (terminal node) | |
1da177e4 | 600 | */ |
4e902c57 TG |
601 | static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, |
602 | struct fib_nh *nh) | |
1da177e4 LT |
603 | { |
604 | int err; | |
86167a37 | 605 | struct net *net; |
6a31d2a9 | 606 | struct net_device *dev; |
1da177e4 | 607 | |
86167a37 | 608 | net = cfg->fc_nlinfo.nl_net; |
1da177e4 LT |
609 | if (nh->nh_gw) { |
610 | struct fib_result res; | |
611 | ||
6a31d2a9 | 612 | if (nh->nh_flags & RTNH_F_ONLINK) { |
1da177e4 | 613 | |
4e902c57 | 614 | if (cfg->fc_scope >= RT_SCOPE_LINK) |
1da177e4 | 615 | return -EINVAL; |
86167a37 | 616 | if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST) |
1da177e4 | 617 | return -EINVAL; |
6a31d2a9 ED |
618 | dev = __dev_get_by_index(net, nh->nh_oif); |
619 | if (!dev) | |
1da177e4 | 620 | return -ENODEV; |
6a31d2a9 | 621 | if (!(dev->flags & IFF_UP)) |
1da177e4 LT |
622 | return -ENETDOWN; |
623 | nh->nh_dev = dev; | |
624 | dev_hold(dev); | |
625 | nh->nh_scope = RT_SCOPE_LINK; | |
626 | return 0; | |
627 | } | |
ebc0ffae | 628 | rcu_read_lock(); |
1da177e4 | 629 | { |
9ade2286 DM |
630 | struct flowi4 fl4 = { |
631 | .daddr = nh->nh_gw, | |
632 | .flowi4_scope = cfg->fc_scope + 1, | |
633 | .flowi4_oif = nh->nh_oif, | |
6a662719 | 634 | .flowi4_iif = LOOPBACK_IFINDEX, |
4e902c57 | 635 | }; |
1da177e4 LT |
636 | |
637 | /* It is not necessary, but requires a bit of thinking */ | |
9ade2286 DM |
638 | if (fl4.flowi4_scope < RT_SCOPE_LINK) |
639 | fl4.flowi4_scope = RT_SCOPE_LINK; | |
640 | err = fib_lookup(net, &fl4, &res); | |
ebc0ffae ED |
641 | if (err) { |
642 | rcu_read_unlock(); | |
1da177e4 | 643 | return err; |
ebc0ffae | 644 | } |
1da177e4 LT |
645 | } |
646 | err = -EINVAL; | |
647 | if (res.type != RTN_UNICAST && res.type != RTN_LOCAL) | |
648 | goto out; | |
649 | nh->nh_scope = res.scope; | |
650 | nh->nh_oif = FIB_RES_OIF(res); | |
6a31d2a9 ED |
651 | nh->nh_dev = dev = FIB_RES_DEV(res); |
652 | if (!dev) | |
1da177e4 | 653 | goto out; |
6a31d2a9 | 654 | dev_hold(dev); |
8723e1b4 | 655 | err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN; |
1da177e4 LT |
656 | } else { |
657 | struct in_device *in_dev; | |
658 | ||
6a31d2a9 | 659 | if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK)) |
1da177e4 LT |
660 | return -EINVAL; |
661 | ||
8723e1b4 ED |
662 | rcu_read_lock(); |
663 | err = -ENODEV; | |
86167a37 | 664 | in_dev = inetdev_by_index(net, nh->nh_oif); |
1da177e4 | 665 | if (in_dev == NULL) |
8723e1b4 ED |
666 | goto out; |
667 | err = -ENETDOWN; | |
668 | if (!(in_dev->dev->flags & IFF_UP)) | |
669 | goto out; | |
1da177e4 LT |
670 | nh->nh_dev = in_dev->dev; |
671 | dev_hold(nh->nh_dev); | |
672 | nh->nh_scope = RT_SCOPE_HOST; | |
8723e1b4 | 673 | err = 0; |
1da177e4 | 674 | } |
8723e1b4 ED |
675 | out: |
676 | rcu_read_unlock(); | |
677 | return err; | |
1da177e4 LT |
678 | } |
679 | ||
81f7bf6c | 680 | static inline unsigned int fib_laddr_hashfn(__be32 val) |
1da177e4 | 681 | { |
123b9731 | 682 | unsigned int mask = (fib_info_hash_size - 1); |
1da177e4 | 683 | |
6a31d2a9 ED |
684 | return ((__force u32)val ^ |
685 | ((__force u32)val >> 7) ^ | |
686 | ((__force u32)val >> 14)) & mask; | |
1da177e4 LT |
687 | } |
688 | ||
123b9731 | 689 | static struct hlist_head *fib_info_hash_alloc(int bytes) |
1da177e4 LT |
690 | { |
691 | if (bytes <= PAGE_SIZE) | |
88f83491 | 692 | return kzalloc(bytes, GFP_KERNEL); |
1da177e4 LT |
693 | else |
694 | return (struct hlist_head *) | |
6a31d2a9 ED |
695 | __get_free_pages(GFP_KERNEL | __GFP_ZERO, |
696 | get_order(bytes)); | |
1da177e4 LT |
697 | } |
698 | ||
123b9731 | 699 | static void fib_info_hash_free(struct hlist_head *hash, int bytes) |
1da177e4 LT |
700 | { |
701 | if (!hash) | |
702 | return; | |
703 | ||
704 | if (bytes <= PAGE_SIZE) | |
705 | kfree(hash); | |
706 | else | |
707 | free_pages((unsigned long) hash, get_order(bytes)); | |
708 | } | |
709 | ||
123b9731 DM |
710 | static void fib_info_hash_move(struct hlist_head *new_info_hash, |
711 | struct hlist_head *new_laddrhash, | |
712 | unsigned int new_size) | |
1da177e4 | 713 | { |
b7656e7f | 714 | struct hlist_head *old_info_hash, *old_laddrhash; |
123b9731 | 715 | unsigned int old_size = fib_info_hash_size; |
b7656e7f | 716 | unsigned int i, bytes; |
1da177e4 | 717 | |
832b4c5e | 718 | spin_lock_bh(&fib_info_lock); |
b7656e7f DM |
719 | old_info_hash = fib_info_hash; |
720 | old_laddrhash = fib_info_laddrhash; | |
123b9731 | 721 | fib_info_hash_size = new_size; |
1da177e4 LT |
722 | |
723 | for (i = 0; i < old_size; i++) { | |
724 | struct hlist_head *head = &fib_info_hash[i]; | |
b67bfe0d | 725 | struct hlist_node *n; |
1da177e4 LT |
726 | struct fib_info *fi; |
727 | ||
b67bfe0d | 728 | hlist_for_each_entry_safe(fi, n, head, fib_hash) { |
1da177e4 LT |
729 | struct hlist_head *dest; |
730 | unsigned int new_hash; | |
731 | ||
732 | hlist_del(&fi->fib_hash); | |
733 | ||
734 | new_hash = fib_info_hashfn(fi); | |
735 | dest = &new_info_hash[new_hash]; | |
736 | hlist_add_head(&fi->fib_hash, dest); | |
737 | } | |
738 | } | |
739 | fib_info_hash = new_info_hash; | |
740 | ||
741 | for (i = 0; i < old_size; i++) { | |
742 | struct hlist_head *lhead = &fib_info_laddrhash[i]; | |
b67bfe0d | 743 | struct hlist_node *n; |
1da177e4 LT |
744 | struct fib_info *fi; |
745 | ||
b67bfe0d | 746 | hlist_for_each_entry_safe(fi, n, lhead, fib_lhash) { |
1da177e4 LT |
747 | struct hlist_head *ldest; |
748 | unsigned int new_hash; | |
749 | ||
750 | hlist_del(&fi->fib_lhash); | |
751 | ||
752 | new_hash = fib_laddr_hashfn(fi->fib_prefsrc); | |
753 | ldest = &new_laddrhash[new_hash]; | |
754 | hlist_add_head(&fi->fib_lhash, ldest); | |
755 | } | |
756 | } | |
757 | fib_info_laddrhash = new_laddrhash; | |
758 | ||
832b4c5e | 759 | spin_unlock_bh(&fib_info_lock); |
b7656e7f DM |
760 | |
761 | bytes = old_size * sizeof(struct hlist_head *); | |
123b9731 DM |
762 | fib_info_hash_free(old_info_hash, bytes); |
763 | fib_info_hash_free(old_laddrhash, bytes); | |
1da177e4 LT |
764 | } |
765 | ||
436c3b66 DM |
766 | __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh) |
767 | { | |
768 | nh->nh_saddr = inet_select_addr(nh->nh_dev, | |
769 | nh->nh_gw, | |
37e826c5 | 770 | nh->nh_parent->fib_scope); |
436c3b66 DM |
771 | nh->nh_saddr_genid = atomic_read(&net->ipv4.dev_addr_genid); |
772 | ||
773 | return nh->nh_saddr; | |
774 | } | |
775 | ||
4e902c57 | 776 | struct fib_info *fib_create_info(struct fib_config *cfg) |
1da177e4 LT |
777 | { |
778 | int err; | |
779 | struct fib_info *fi = NULL; | |
780 | struct fib_info *ofi; | |
1da177e4 | 781 | int nhs = 1; |
7462bd74 | 782 | struct net *net = cfg->fc_nlinfo.nl_net; |
1da177e4 | 783 | |
4c8237cd DM |
784 | if (cfg->fc_type > RTN_MAX) |
785 | goto err_inval; | |
786 | ||
1da177e4 | 787 | /* Fast check to catch the most weird cases */ |
4e902c57 | 788 | if (fib_props[cfg->fc_type].scope > cfg->fc_scope) |
1da177e4 LT |
789 | goto err_inval; |
790 | ||
791 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
4e902c57 TG |
792 | if (cfg->fc_mp) { |
793 | nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len); | |
1da177e4 LT |
794 | if (nhs == 0) |
795 | goto err_inval; | |
796 | } | |
797 | #endif | |
1da177e4 LT |
798 | |
799 | err = -ENOBUFS; | |
123b9731 DM |
800 | if (fib_info_cnt >= fib_info_hash_size) { |
801 | unsigned int new_size = fib_info_hash_size << 1; | |
1da177e4 LT |
802 | struct hlist_head *new_info_hash; |
803 | struct hlist_head *new_laddrhash; | |
804 | unsigned int bytes; | |
805 | ||
806 | if (!new_size) | |
d94ce9b2 | 807 | new_size = 16; |
1da177e4 | 808 | bytes = new_size * sizeof(struct hlist_head *); |
123b9731 DM |
809 | new_info_hash = fib_info_hash_alloc(bytes); |
810 | new_laddrhash = fib_info_hash_alloc(bytes); | |
1da177e4 | 811 | if (!new_info_hash || !new_laddrhash) { |
123b9731 DM |
812 | fib_info_hash_free(new_info_hash, bytes); |
813 | fib_info_hash_free(new_laddrhash, bytes); | |
88f83491 | 814 | } else |
123b9731 | 815 | fib_info_hash_move(new_info_hash, new_laddrhash, new_size); |
1da177e4 | 816 | |
123b9731 | 817 | if (!fib_info_hash_size) |
1da177e4 LT |
818 | goto failure; |
819 | } | |
820 | ||
0da974f4 | 821 | fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct fib_nh), GFP_KERNEL); |
1da177e4 LT |
822 | if (fi == NULL) |
823 | goto failure; | |
aeefa1ec | 824 | fib_info_cnt++; |
725d1e1b DM |
825 | if (cfg->fc_mx) { |
826 | fi->fib_metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL); | |
827 | if (!fi->fib_metrics) | |
828 | goto failure; | |
829 | } else | |
830 | fi->fib_metrics = (u32 *) dst_default_metrics; | |
1da177e4 | 831 | |
57d7a600 | 832 | fi->fib_net = hold_net(net); |
4e902c57 | 833 | fi->fib_protocol = cfg->fc_protocol; |
37e826c5 | 834 | fi->fib_scope = cfg->fc_scope; |
4e902c57 TG |
835 | fi->fib_flags = cfg->fc_flags; |
836 | fi->fib_priority = cfg->fc_priority; | |
837 | fi->fib_prefsrc = cfg->fc_prefsrc; | |
f4ef85bb | 838 | fi->fib_type = cfg->fc_type; |
1da177e4 LT |
839 | |
840 | fi->fib_nhs = nhs; | |
841 | change_nexthops(fi) { | |
71fceff0 | 842 | nexthop_nh->nh_parent = fi; |
d26b3a7c | 843 | nexthop_nh->nh_pcpu_rth_output = alloc_percpu(struct rtable __rcu *); |
f8a17175 JA |
844 | if (!nexthop_nh->nh_pcpu_rth_output) |
845 | goto failure; | |
1da177e4 LT |
846 | } endfor_nexthops(fi) |
847 | ||
4e902c57 TG |
848 | if (cfg->fc_mx) { |
849 | struct nlattr *nla; | |
850 | int remaining; | |
851 | ||
852 | nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { | |
8f4c1f9b | 853 | int type = nla_type(nla); |
4e902c57 TG |
854 | |
855 | if (type) { | |
6fac2625 DM |
856 | u32 val; |
857 | ||
4e902c57 | 858 | if (type > RTAX_MAX) |
1da177e4 | 859 | goto err_inval; |
6fac2625 DM |
860 | val = nla_get_u32(nla); |
861 | if (type == RTAX_ADVMSS && val > 65535 - 40) | |
862 | val = 65535 - 40; | |
710ab6c0 DM |
863 | if (type == RTAX_MTU && val > 65535 - 15) |
864 | val = 65535 - 15; | |
6fac2625 | 865 | fi->fib_metrics[type - 1] = val; |
1da177e4 | 866 | } |
1da177e4 LT |
867 | } |
868 | } | |
1da177e4 | 869 | |
4e902c57 | 870 | if (cfg->fc_mp) { |
1da177e4 | 871 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
4e902c57 TG |
872 | err = fib_get_nhs(fi, cfg->fc_mp, cfg->fc_mp_len, cfg); |
873 | if (err != 0) | |
1da177e4 | 874 | goto failure; |
4e902c57 | 875 | if (cfg->fc_oif && fi->fib_nh->nh_oif != cfg->fc_oif) |
1da177e4 | 876 | goto err_inval; |
4e902c57 | 877 | if (cfg->fc_gw && fi->fib_nh->nh_gw != cfg->fc_gw) |
1da177e4 | 878 | goto err_inval; |
c7066f70 | 879 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 | 880 | if (cfg->fc_flow && fi->fib_nh->nh_tclassid != cfg->fc_flow) |
1da177e4 LT |
881 | goto err_inval; |
882 | #endif | |
883 | #else | |
884 | goto err_inval; | |
885 | #endif | |
886 | } else { | |
887 | struct fib_nh *nh = fi->fib_nh; | |
4e902c57 TG |
888 | |
889 | nh->nh_oif = cfg->fc_oif; | |
890 | nh->nh_gw = cfg->fc_gw; | |
891 | nh->nh_flags = cfg->fc_flags; | |
c7066f70 | 892 | #ifdef CONFIG_IP_ROUTE_CLASSID |
4e902c57 | 893 | nh->nh_tclassid = cfg->fc_flow; |
7a9bc9b8 | 894 | if (nh->nh_tclassid) |
f4530fa5 | 895 | fi->fib_net->ipv4.fib_num_tclassid_users++; |
1da177e4 | 896 | #endif |
1da177e4 LT |
897 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
898 | nh->nh_weight = 1; | |
899 | #endif | |
900 | } | |
901 | ||
4e902c57 TG |
902 | if (fib_props[cfg->fc_type].error) { |
903 | if (cfg->fc_gw || cfg->fc_oif || cfg->fc_mp) | |
1da177e4 LT |
904 | goto err_inval; |
905 | goto link_it; | |
4c8237cd DM |
906 | } else { |
907 | switch (cfg->fc_type) { | |
908 | case RTN_UNICAST: | |
909 | case RTN_LOCAL: | |
910 | case RTN_BROADCAST: | |
911 | case RTN_ANYCAST: | |
912 | case RTN_MULTICAST: | |
913 | break; | |
914 | default: | |
915 | goto err_inval; | |
916 | } | |
1da177e4 LT |
917 | } |
918 | ||
4e902c57 | 919 | if (cfg->fc_scope > RT_SCOPE_HOST) |
1da177e4 LT |
920 | goto err_inval; |
921 | ||
4e902c57 | 922 | if (cfg->fc_scope == RT_SCOPE_HOST) { |
1da177e4 LT |
923 | struct fib_nh *nh = fi->fib_nh; |
924 | ||
925 | /* Local address is added. */ | |
926 | if (nhs != 1 || nh->nh_gw) | |
927 | goto err_inval; | |
928 | nh->nh_scope = RT_SCOPE_NOWHERE; | |
7462bd74 | 929 | nh->nh_dev = dev_get_by_index(net, fi->fib_nh->nh_oif); |
1da177e4 LT |
930 | err = -ENODEV; |
931 | if (nh->nh_dev == NULL) | |
932 | goto failure; | |
933 | } else { | |
934 | change_nexthops(fi) { | |
6a31d2a9 ED |
935 | err = fib_check_nh(cfg, fi, nexthop_nh); |
936 | if (err != 0) | |
1da177e4 LT |
937 | goto failure; |
938 | } endfor_nexthops(fi) | |
939 | } | |
940 | ||
941 | if (fi->fib_prefsrc) { | |
4e902c57 TG |
942 | if (cfg->fc_type != RTN_LOCAL || !cfg->fc_dst || |
943 | fi->fib_prefsrc != cfg->fc_dst) | |
7462bd74 | 944 | if (inet_addr_type(net, fi->fib_prefsrc) != RTN_LOCAL) |
1da177e4 LT |
945 | goto err_inval; |
946 | } | |
947 | ||
1fc050a1 | 948 | change_nexthops(fi) { |
436c3b66 | 949 | fib_info_update_nh_saddr(net, nexthop_nh); |
1fc050a1 DM |
950 | } endfor_nexthops(fi) |
951 | ||
1da177e4 | 952 | link_it: |
6a31d2a9 ED |
953 | ofi = fib_find_info(fi); |
954 | if (ofi) { | |
1da177e4 LT |
955 | fi->fib_dead = 1; |
956 | free_fib_info(fi); | |
957 | ofi->fib_treeref++; | |
958 | return ofi; | |
959 | } | |
960 | ||
961 | fi->fib_treeref++; | |
962 | atomic_inc(&fi->fib_clntref); | |
832b4c5e | 963 | spin_lock_bh(&fib_info_lock); |
1da177e4 LT |
964 | hlist_add_head(&fi->fib_hash, |
965 | &fib_info_hash[fib_info_hashfn(fi)]); | |
966 | if (fi->fib_prefsrc) { | |
967 | struct hlist_head *head; | |
968 | ||
969 | head = &fib_info_laddrhash[fib_laddr_hashfn(fi->fib_prefsrc)]; | |
970 | hlist_add_head(&fi->fib_lhash, head); | |
971 | } | |
972 | change_nexthops(fi) { | |
973 | struct hlist_head *head; | |
974 | unsigned int hash; | |
975 | ||
71fceff0 | 976 | if (!nexthop_nh->nh_dev) |
1da177e4 | 977 | continue; |
71fceff0 | 978 | hash = fib_devindex_hashfn(nexthop_nh->nh_dev->ifindex); |
1da177e4 | 979 | head = &fib_info_devhash[hash]; |
71fceff0 | 980 | hlist_add_head(&nexthop_nh->nh_hash, head); |
1da177e4 | 981 | } endfor_nexthops(fi) |
832b4c5e | 982 | spin_unlock_bh(&fib_info_lock); |
1da177e4 LT |
983 | return fi; |
984 | ||
985 | err_inval: | |
986 | err = -EINVAL; | |
987 | ||
988 | failure: | |
e905a9ed | 989 | if (fi) { |
1da177e4 LT |
990 | fi->fib_dead = 1; |
991 | free_fib_info(fi); | |
992 | } | |
4e902c57 TG |
993 | |
994 | return ERR_PTR(err); | |
1da177e4 LT |
995 | } |
996 | ||
15e47304 | 997 | int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event, |
37e826c5 | 998 | u32 tb_id, u8 type, __be32 dst, int dst_len, u8 tos, |
be403ea1 | 999 | struct fib_info *fi, unsigned int flags) |
1da177e4 | 1000 | { |
be403ea1 | 1001 | struct nlmsghdr *nlh; |
1da177e4 | 1002 | struct rtmsg *rtm; |
1da177e4 | 1003 | |
15e47304 | 1004 | nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); |
be403ea1 | 1005 | if (nlh == NULL) |
26932566 | 1006 | return -EMSGSIZE; |
be403ea1 TG |
1007 | |
1008 | rtm = nlmsg_data(nlh); | |
1da177e4 LT |
1009 | rtm->rtm_family = AF_INET; |
1010 | rtm->rtm_dst_len = dst_len; | |
1011 | rtm->rtm_src_len = 0; | |
1012 | rtm->rtm_tos = tos; | |
709772e6 KPO |
1013 | if (tb_id < 256) |
1014 | rtm->rtm_table = tb_id; | |
1015 | else | |
1016 | rtm->rtm_table = RT_TABLE_COMPAT; | |
f3756b79 DM |
1017 | if (nla_put_u32(skb, RTA_TABLE, tb_id)) |
1018 | goto nla_put_failure; | |
1da177e4 LT |
1019 | rtm->rtm_type = type; |
1020 | rtm->rtm_flags = fi->fib_flags; | |
37e826c5 | 1021 | rtm->rtm_scope = fi->fib_scope; |
1da177e4 | 1022 | rtm->rtm_protocol = fi->fib_protocol; |
be403ea1 | 1023 | |
f3756b79 DM |
1024 | if (rtm->rtm_dst_len && |
1025 | nla_put_be32(skb, RTA_DST, dst)) | |
1026 | goto nla_put_failure; | |
1027 | if (fi->fib_priority && | |
1028 | nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority)) | |
1029 | goto nla_put_failure; | |
1da177e4 | 1030 | if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0) |
be403ea1 TG |
1031 | goto nla_put_failure; |
1032 | ||
f3756b79 DM |
1033 | if (fi->fib_prefsrc && |
1034 | nla_put_be32(skb, RTA_PREFSRC, fi->fib_prefsrc)) | |
1035 | goto nla_put_failure; | |
1da177e4 | 1036 | if (fi->fib_nhs == 1) { |
f3756b79 DM |
1037 | if (fi->fib_nh->nh_gw && |
1038 | nla_put_be32(skb, RTA_GATEWAY, fi->fib_nh->nh_gw)) | |
1039 | goto nla_put_failure; | |
1040 | if (fi->fib_nh->nh_oif && | |
1041 | nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif)) | |
1042 | goto nla_put_failure; | |
c7066f70 | 1043 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
1044 | if (fi->fib_nh[0].nh_tclassid && |
1045 | nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid)) | |
1046 | goto nla_put_failure; | |
8265abc0 | 1047 | #endif |
1da177e4 LT |
1048 | } |
1049 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
1050 | if (fi->fib_nhs > 1) { | |
be403ea1 TG |
1051 | struct rtnexthop *rtnh; |
1052 | struct nlattr *mp; | |
1053 | ||
1054 | mp = nla_nest_start(skb, RTA_MULTIPATH); | |
1055 | if (mp == NULL) | |
1056 | goto nla_put_failure; | |
1da177e4 LT |
1057 | |
1058 | for_nexthops(fi) { | |
be403ea1 TG |
1059 | rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); |
1060 | if (rtnh == NULL) | |
1061 | goto nla_put_failure; | |
1062 | ||
1063 | rtnh->rtnh_flags = nh->nh_flags & 0xFF; | |
1064 | rtnh->rtnh_hops = nh->nh_weight - 1; | |
1065 | rtnh->rtnh_ifindex = nh->nh_oif; | |
1066 | ||
f3756b79 DM |
1067 | if (nh->nh_gw && |
1068 | nla_put_be32(skb, RTA_GATEWAY, nh->nh_gw)) | |
1069 | goto nla_put_failure; | |
c7066f70 | 1070 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
1071 | if (nh->nh_tclassid && |
1072 | nla_put_u32(skb, RTA_FLOW, nh->nh_tclassid)) | |
1073 | goto nla_put_failure; | |
8265abc0 | 1074 | #endif |
be403ea1 TG |
1075 | /* length of rtnetlink header + attributes */ |
1076 | rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *) rtnh; | |
1da177e4 | 1077 | } endfor_nexthops(fi); |
be403ea1 TG |
1078 | |
1079 | nla_nest_end(skb, mp); | |
1da177e4 LT |
1080 | } |
1081 | #endif | |
be403ea1 | 1082 | return nlmsg_end(skb, nlh); |
1da177e4 | 1083 | |
be403ea1 | 1084 | nla_put_failure: |
26932566 PM |
1085 | nlmsg_cancel(skb, nlh); |
1086 | return -EMSGSIZE; | |
1da177e4 LT |
1087 | } |
1088 | ||
1da177e4 | 1089 | /* |
6a31d2a9 ED |
1090 | * Update FIB if: |
1091 | * - local address disappeared -> we must delete all the entries | |
1092 | * referring to it. | |
1093 | * - device went down -> we must shutdown all nexthops going via it. | |
1da177e4 | 1094 | */ |
4814bdbd | 1095 | int fib_sync_down_addr(struct net *net, __be32 local) |
1da177e4 LT |
1096 | { |
1097 | int ret = 0; | |
85326fa5 DL |
1098 | unsigned int hash = fib_laddr_hashfn(local); |
1099 | struct hlist_head *head = &fib_info_laddrhash[hash]; | |
85326fa5 | 1100 | struct fib_info *fi; |
1da177e4 | 1101 | |
85326fa5 DL |
1102 | if (fib_info_laddrhash == NULL || local == 0) |
1103 | return 0; | |
1da177e4 | 1104 | |
b67bfe0d | 1105 | hlist_for_each_entry(fi, head, fib_lhash) { |
09ad9bc7 | 1106 | if (!net_eq(fi->fib_net, net)) |
4814bdbd | 1107 | continue; |
85326fa5 DL |
1108 | if (fi->fib_prefsrc == local) { |
1109 | fi->fib_flags |= RTNH_F_DEAD; | |
1110 | ret++; | |
1da177e4 LT |
1111 | } |
1112 | } | |
85326fa5 DL |
1113 | return ret; |
1114 | } | |
1115 | ||
1116 | int fib_sync_down_dev(struct net_device *dev, int force) | |
1117 | { | |
1118 | int ret = 0; | |
1119 | int scope = RT_SCOPE_NOWHERE; | |
1120 | struct fib_info *prev_fi = NULL; | |
1121 | unsigned int hash = fib_devindex_hashfn(dev->ifindex); | |
1122 | struct hlist_head *head = &fib_info_devhash[hash]; | |
85326fa5 | 1123 | struct fib_nh *nh; |
1da177e4 | 1124 | |
85326fa5 DL |
1125 | if (force) |
1126 | scope = -1; | |
1da177e4 | 1127 | |
b67bfe0d | 1128 | hlist_for_each_entry(nh, head, nh_hash) { |
85326fa5 DL |
1129 | struct fib_info *fi = nh->nh_parent; |
1130 | int dead; | |
1da177e4 | 1131 | |
85326fa5 DL |
1132 | BUG_ON(!fi->fib_nhs); |
1133 | if (nh->nh_dev != dev || fi == prev_fi) | |
1134 | continue; | |
1135 | prev_fi = fi; | |
1136 | dead = 0; | |
1137 | change_nexthops(fi) { | |
6a31d2a9 | 1138 | if (nexthop_nh->nh_flags & RTNH_F_DEAD) |
85326fa5 | 1139 | dead++; |
71fceff0 DM |
1140 | else if (nexthop_nh->nh_dev == dev && |
1141 | nexthop_nh->nh_scope != scope) { | |
1142 | nexthop_nh->nh_flags |= RTNH_F_DEAD; | |
1da177e4 | 1143 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
85326fa5 | 1144 | spin_lock_bh(&fib_multipath_lock); |
71fceff0 DM |
1145 | fi->fib_power -= nexthop_nh->nh_power; |
1146 | nexthop_nh->nh_power = 0; | |
85326fa5 | 1147 | spin_unlock_bh(&fib_multipath_lock); |
1da177e4 | 1148 | #endif |
85326fa5 DL |
1149 | dead++; |
1150 | } | |
1da177e4 | 1151 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
71fceff0 | 1152 | if (force > 1 && nexthop_nh->nh_dev == dev) { |
85326fa5 DL |
1153 | dead = fi->fib_nhs; |
1154 | break; | |
1da177e4 | 1155 | } |
85326fa5 DL |
1156 | #endif |
1157 | } endfor_nexthops(fi) | |
1158 | if (dead == fi->fib_nhs) { | |
1159 | fi->fib_flags |= RTNH_F_DEAD; | |
1160 | ret++; | |
1da177e4 LT |
1161 | } |
1162 | } | |
1163 | ||
1164 | return ret; | |
1165 | } | |
1166 | ||
0c838ff1 DM |
1167 | /* Must be invoked inside of an RCU protected region. */ |
1168 | void fib_select_default(struct fib_result *res) | |
1169 | { | |
1170 | struct fib_info *fi = NULL, *last_resort = NULL; | |
1171 | struct list_head *fa_head = res->fa_head; | |
1172 | struct fib_table *tb = res->table; | |
1173 | int order = -1, last_idx = -1; | |
1174 | struct fib_alias *fa; | |
1175 | ||
1176 | list_for_each_entry_rcu(fa, fa_head, fa_list) { | |
1177 | struct fib_info *next_fi = fa->fa_info; | |
1178 | ||
37e826c5 | 1179 | if (next_fi->fib_scope != res->scope || |
0c838ff1 DM |
1180 | fa->fa_type != RTN_UNICAST) |
1181 | continue; | |
1182 | ||
1183 | if (next_fi->fib_priority > res->fi->fib_priority) | |
1184 | break; | |
1185 | if (!next_fi->fib_nh[0].nh_gw || | |
1186 | next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK) | |
1187 | continue; | |
1188 | ||
1189 | fib_alias_accessed(fa); | |
1190 | ||
1191 | if (fi == NULL) { | |
1192 | if (next_fi != res->fi) | |
1193 | break; | |
1194 | } else if (!fib_detect_death(fi, order, &last_resort, | |
1195 | &last_idx, tb->tb_default)) { | |
1196 | fib_result_assign(res, fi); | |
1197 | tb->tb_default = order; | |
1198 | goto out; | |
1199 | } | |
1200 | fi = next_fi; | |
1201 | order++; | |
1202 | } | |
1203 | ||
1204 | if (order <= 0 || fi == NULL) { | |
1205 | tb->tb_default = -1; | |
1206 | goto out; | |
1207 | } | |
1208 | ||
1209 | if (!fib_detect_death(fi, order, &last_resort, &last_idx, | |
1210 | tb->tb_default)) { | |
1211 | fib_result_assign(res, fi); | |
1212 | tb->tb_default = order; | |
1213 | goto out; | |
1214 | } | |
1215 | ||
1216 | if (last_idx >= 0) | |
1217 | fib_result_assign(res, last_resort); | |
1218 | tb->tb_default = last_idx; | |
1219 | out: | |
31d40937 | 1220 | return; |
0c838ff1 DM |
1221 | } |
1222 | ||
1da177e4 LT |
1223 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
1224 | ||
1225 | /* | |
6a31d2a9 ED |
1226 | * Dead device goes up. We wake up dead nexthops. |
1227 | * It takes sense only on multipath routes. | |
1da177e4 | 1228 | */ |
1da177e4 LT |
1229 | int fib_sync_up(struct net_device *dev) |
1230 | { | |
1231 | struct fib_info *prev_fi; | |
1232 | unsigned int hash; | |
1233 | struct hlist_head *head; | |
1da177e4 LT |
1234 | struct fib_nh *nh; |
1235 | int ret; | |
1236 | ||
6a31d2a9 | 1237 | if (!(dev->flags & IFF_UP)) |
1da177e4 LT |
1238 | return 0; |
1239 | ||
1240 | prev_fi = NULL; | |
1241 | hash = fib_devindex_hashfn(dev->ifindex); | |
1242 | head = &fib_info_devhash[hash]; | |
1243 | ret = 0; | |
1244 | ||
b67bfe0d | 1245 | hlist_for_each_entry(nh, head, nh_hash) { |
1da177e4 LT |
1246 | struct fib_info *fi = nh->nh_parent; |
1247 | int alive; | |
1248 | ||
1249 | BUG_ON(!fi->fib_nhs); | |
1250 | if (nh->nh_dev != dev || fi == prev_fi) | |
1251 | continue; | |
1252 | ||
1253 | prev_fi = fi; | |
1254 | alive = 0; | |
1255 | change_nexthops(fi) { | |
6a31d2a9 | 1256 | if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { |
1da177e4 LT |
1257 | alive++; |
1258 | continue; | |
1259 | } | |
71fceff0 | 1260 | if (nexthop_nh->nh_dev == NULL || |
6a31d2a9 | 1261 | !(nexthop_nh->nh_dev->flags & IFF_UP)) |
1da177e4 | 1262 | continue; |
71fceff0 DM |
1263 | if (nexthop_nh->nh_dev != dev || |
1264 | !__in_dev_get_rtnl(dev)) | |
1da177e4 LT |
1265 | continue; |
1266 | alive++; | |
1267 | spin_lock_bh(&fib_multipath_lock); | |
71fceff0 DM |
1268 | nexthop_nh->nh_power = 0; |
1269 | nexthop_nh->nh_flags &= ~RTNH_F_DEAD; | |
1da177e4 LT |
1270 | spin_unlock_bh(&fib_multipath_lock); |
1271 | } endfor_nexthops(fi) | |
1272 | ||
1273 | if (alive > 0) { | |
1274 | fi->fib_flags &= ~RTNH_F_DEAD; | |
1275 | ret++; | |
1276 | } | |
1277 | } | |
1278 | ||
1279 | return ret; | |
1280 | } | |
1281 | ||
1282 | /* | |
6a31d2a9 ED |
1283 | * The algorithm is suboptimal, but it provides really |
1284 | * fair weighted route distribution. | |
1da177e4 | 1285 | */ |
1b7fe593 | 1286 | void fib_select_multipath(struct fib_result *res) |
1da177e4 LT |
1287 | { |
1288 | struct fib_info *fi = res->fi; | |
1289 | int w; | |
1290 | ||
1291 | spin_lock_bh(&fib_multipath_lock); | |
1292 | if (fi->fib_power <= 0) { | |
1293 | int power = 0; | |
1294 | change_nexthops(fi) { | |
6a31d2a9 | 1295 | if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { |
71fceff0 DM |
1296 | power += nexthop_nh->nh_weight; |
1297 | nexthop_nh->nh_power = nexthop_nh->nh_weight; | |
1da177e4 LT |
1298 | } |
1299 | } endfor_nexthops(fi); | |
1300 | fi->fib_power = power; | |
1301 | if (power <= 0) { | |
1302 | spin_unlock_bh(&fib_multipath_lock); | |
1303 | /* Race condition: route has just become dead. */ | |
1304 | res->nh_sel = 0; | |
1305 | return; | |
1306 | } | |
1307 | } | |
1308 | ||
1309 | ||
1310 | /* w should be random number [0..fi->fib_power-1], | |
6a31d2a9 | 1311 | * it is pretty bad approximation. |
1da177e4 LT |
1312 | */ |
1313 | ||
1314 | w = jiffies % fi->fib_power; | |
1315 | ||
1316 | change_nexthops(fi) { | |
6a31d2a9 | 1317 | if (!(nexthop_nh->nh_flags & RTNH_F_DEAD) && |
71fceff0 | 1318 | nexthop_nh->nh_power) { |
6a31d2a9 ED |
1319 | w -= nexthop_nh->nh_power; |
1320 | if (w <= 0) { | |
71fceff0 | 1321 | nexthop_nh->nh_power--; |
1da177e4 LT |
1322 | fi->fib_power--; |
1323 | res->nh_sel = nhsel; | |
1324 | spin_unlock_bh(&fib_multipath_lock); | |
1325 | return; | |
1326 | } | |
1327 | } | |
1328 | } endfor_nexthops(fi); | |
1329 | ||
1330 | /* Race condition: route has just become dead. */ | |
1331 | res->nh_sel = 0; | |
1332 | spin_unlock_bh(&fib_multipath_lock); | |
1333 | } | |
1334 | #endif |