]>
Commit | Line | Data |
---|---|---|
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: FIB frontend. | |
7 | * | |
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 | ||
16 | #include <linux/module.h> | |
17 | #include <linux/uaccess.h> | |
18 | #include <linux/bitops.h> | |
19 | #include <linux/capability.h> | |
20 | #include <linux/types.h> | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/mm.h> | |
23 | #include <linux/string.h> | |
24 | #include <linux/socket.h> | |
25 | #include <linux/sockios.h> | |
26 | #include <linux/errno.h> | |
27 | #include <linux/in.h> | |
28 | #include <linux/inet.h> | |
29 | #include <linux/inetdevice.h> | |
30 | #include <linux/netdevice.h> | |
31 | #include <linux/if_addr.h> | |
32 | #include <linux/if_arp.h> | |
33 | #include <linux/skbuff.h> | |
34 | #include <linux/cache.h> | |
35 | #include <linux/init.h> | |
36 | #include <linux/list.h> | |
37 | #include <linux/slab.h> | |
38 | ||
39 | #include <net/ip.h> | |
40 | #include <net/protocol.h> | |
41 | #include <net/route.h> | |
42 | #include <net/tcp.h> | |
43 | #include <net/sock.h> | |
44 | #include <net/arp.h> | |
45 | #include <net/ip_fib.h> | |
46 | #include <net/rtnetlink.h> | |
47 | #include <net/xfrm.h> | |
48 | #include <net/l3mdev.h> | |
49 | #include <net/lwtunnel.h> | |
50 | #include <trace/events/fib.h> | |
51 | ||
52 | #ifndef CONFIG_IP_MULTIPLE_TABLES | |
53 | ||
54 | static int __net_init fib4_rules_init(struct net *net) | |
55 | { | |
56 | struct fib_table *local_table, *main_table; | |
57 | ||
58 | main_table = fib_trie_table(RT_TABLE_MAIN, NULL); | |
59 | if (!main_table) | |
60 | return -ENOMEM; | |
61 | ||
62 | local_table = fib_trie_table(RT_TABLE_LOCAL, main_table); | |
63 | if (!local_table) | |
64 | goto fail; | |
65 | ||
66 | hlist_add_head_rcu(&local_table->tb_hlist, | |
67 | &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]); | |
68 | hlist_add_head_rcu(&main_table->tb_hlist, | |
69 | &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]); | |
70 | return 0; | |
71 | ||
72 | fail: | |
73 | fib_free_table(main_table); | |
74 | return -ENOMEM; | |
75 | } | |
76 | ||
77 | static bool fib4_has_custom_rules(struct net *net) | |
78 | { | |
79 | return false; | |
80 | } | |
81 | #else | |
82 | ||
83 | struct fib_table *fib_new_table(struct net *net, u32 id) | |
84 | { | |
85 | struct fib_table *tb, *alias = NULL; | |
86 | unsigned int h; | |
87 | ||
88 | if (id == 0) | |
89 | id = RT_TABLE_MAIN; | |
90 | tb = fib_get_table(net, id); | |
91 | if (tb) | |
92 | return tb; | |
93 | ||
94 | if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules) | |
95 | alias = fib_new_table(net, RT_TABLE_MAIN); | |
96 | ||
97 | tb = fib_trie_table(id, alias); | |
98 | if (!tb) | |
99 | return NULL; | |
100 | ||
101 | switch (id) { | |
102 | case RT_TABLE_MAIN: | |
103 | rcu_assign_pointer(net->ipv4.fib_main, tb); | |
104 | break; | |
105 | case RT_TABLE_DEFAULT: | |
106 | rcu_assign_pointer(net->ipv4.fib_default, tb); | |
107 | break; | |
108 | default: | |
109 | break; | |
110 | } | |
111 | ||
112 | h = id & (FIB_TABLE_HASHSZ - 1); | |
113 | hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]); | |
114 | return tb; | |
115 | } | |
116 | EXPORT_SYMBOL_GPL(fib_new_table); | |
117 | ||
118 | /* caller must hold either rtnl or rcu read lock */ | |
119 | struct fib_table *fib_get_table(struct net *net, u32 id) | |
120 | { | |
121 | struct fib_table *tb; | |
122 | struct hlist_head *head; | |
123 | unsigned int h; | |
124 | ||
125 | if (id == 0) | |
126 | id = RT_TABLE_MAIN; | |
127 | h = id & (FIB_TABLE_HASHSZ - 1); | |
128 | ||
129 | head = &net->ipv4.fib_table_hash[h]; | |
130 | hlist_for_each_entry_rcu(tb, head, tb_hlist) { | |
131 | if (tb->tb_id == id) | |
132 | return tb; | |
133 | } | |
134 | return NULL; | |
135 | } | |
136 | ||
137 | static bool fib4_has_custom_rules(struct net *net) | |
138 | { | |
139 | return net->ipv4.fib_has_custom_rules; | |
140 | } | |
141 | #endif /* CONFIG_IP_MULTIPLE_TABLES */ | |
142 | ||
143 | static void fib_replace_table(struct net *net, struct fib_table *old, | |
144 | struct fib_table *new) | |
145 | { | |
146 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
147 | switch (new->tb_id) { | |
148 | case RT_TABLE_MAIN: | |
149 | rcu_assign_pointer(net->ipv4.fib_main, new); | |
150 | break; | |
151 | case RT_TABLE_DEFAULT: | |
152 | rcu_assign_pointer(net->ipv4.fib_default, new); | |
153 | break; | |
154 | default: | |
155 | break; | |
156 | } | |
157 | ||
158 | #endif | |
159 | /* replace the old table in the hlist */ | |
160 | hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist); | |
161 | } | |
162 | ||
163 | int fib_unmerge(struct net *net) | |
164 | { | |
165 | struct fib_table *old, *new, *main_table; | |
166 | ||
167 | /* attempt to fetch local table if it has been allocated */ | |
168 | old = fib_get_table(net, RT_TABLE_LOCAL); | |
169 | if (!old) | |
170 | return 0; | |
171 | ||
172 | new = fib_trie_unmerge(old); | |
173 | if (!new) | |
174 | return -ENOMEM; | |
175 | ||
176 | /* table is already unmerged */ | |
177 | if (new == old) | |
178 | return 0; | |
179 | ||
180 | /* replace merged table with clean table */ | |
181 | fib_replace_table(net, old, new); | |
182 | fib_free_table(old); | |
183 | ||
184 | /* attempt to fetch main table if it has been allocated */ | |
185 | main_table = fib_get_table(net, RT_TABLE_MAIN); | |
186 | if (!main_table) | |
187 | return 0; | |
188 | ||
189 | /* flush local entries from main table */ | |
190 | fib_table_flush_external(main_table); | |
191 | ||
192 | return 0; | |
193 | } | |
194 | ||
195 | static void fib_flush(struct net *net) | |
196 | { | |
197 | int flushed = 0; | |
198 | unsigned int h; | |
199 | ||
200 | for (h = 0; h < FIB_TABLE_HASHSZ; h++) { | |
201 | struct hlist_head *head = &net->ipv4.fib_table_hash[h]; | |
202 | struct hlist_node *tmp; | |
203 | struct fib_table *tb; | |
204 | ||
205 | hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) | |
206 | flushed += fib_table_flush(net, tb, false); | |
207 | } | |
208 | ||
209 | if (flushed) | |
210 | rt_cache_flush(net); | |
211 | } | |
212 | ||
213 | /* | |
214 | * Find address type as if only "dev" was present in the system. If | |
215 | * on_dev is NULL then all interfaces are taken into consideration. | |
216 | */ | |
217 | static inline unsigned int __inet_dev_addr_type(struct net *net, | |
218 | const struct net_device *dev, | |
219 | __be32 addr, u32 tb_id) | |
220 | { | |
221 | struct flowi4 fl4 = { .daddr = addr }; | |
222 | struct fib_result res; | |
223 | unsigned int ret = RTN_BROADCAST; | |
224 | struct fib_table *table; | |
225 | ||
226 | if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) | |
227 | return RTN_BROADCAST; | |
228 | if (ipv4_is_multicast(addr)) | |
229 | return RTN_MULTICAST; | |
230 | ||
231 | rcu_read_lock(); | |
232 | ||
233 | table = fib_get_table(net, tb_id); | |
234 | if (table) { | |
235 | ret = RTN_UNICAST; | |
236 | if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) { | |
237 | if (!dev || dev == res.fi->fib_dev) | |
238 | ret = res.type; | |
239 | } | |
240 | } | |
241 | ||
242 | rcu_read_unlock(); | |
243 | return ret; | |
244 | } | |
245 | ||
246 | unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id) | |
247 | { | |
248 | return __inet_dev_addr_type(net, NULL, addr, tb_id); | |
249 | } | |
250 | EXPORT_SYMBOL(inet_addr_type_table); | |
251 | ||
252 | unsigned int inet_addr_type(struct net *net, __be32 addr) | |
253 | { | |
254 | return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL); | |
255 | } | |
256 | EXPORT_SYMBOL(inet_addr_type); | |
257 | ||
258 | unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, | |
259 | __be32 addr) | |
260 | { | |
261 | u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; | |
262 | ||
263 | return __inet_dev_addr_type(net, dev, addr, rt_table); | |
264 | } | |
265 | EXPORT_SYMBOL(inet_dev_addr_type); | |
266 | ||
267 | /* inet_addr_type with dev == NULL but using the table from a dev | |
268 | * if one is associated | |
269 | */ | |
270 | unsigned int inet_addr_type_dev_table(struct net *net, | |
271 | const struct net_device *dev, | |
272 | __be32 addr) | |
273 | { | |
274 | u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; | |
275 | ||
276 | return __inet_dev_addr_type(net, NULL, addr, rt_table); | |
277 | } | |
278 | EXPORT_SYMBOL(inet_addr_type_dev_table); | |
279 | ||
280 | __be32 fib_compute_spec_dst(struct sk_buff *skb) | |
281 | { | |
282 | struct net_device *dev = skb->dev; | |
283 | struct in_device *in_dev; | |
284 | struct fib_result res; | |
285 | struct rtable *rt; | |
286 | struct net *net; | |
287 | int scope; | |
288 | ||
289 | rt = skb_rtable(skb); | |
290 | if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) == | |
291 | RTCF_LOCAL) | |
292 | return ip_hdr(skb)->daddr; | |
293 | ||
294 | in_dev = __in_dev_get_rcu(dev); | |
295 | ||
296 | net = dev_net(dev); | |
297 | ||
298 | scope = RT_SCOPE_UNIVERSE; | |
299 | if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) { | |
300 | bool vmark = in_dev && IN_DEV_SRC_VMARK(in_dev); | |
301 | struct flowi4 fl4 = { | |
302 | .flowi4_iif = LOOPBACK_IFINDEX, | |
303 | .flowi4_oif = l3mdev_master_ifindex_rcu(dev), | |
304 | .daddr = ip_hdr(skb)->saddr, | |
305 | .flowi4_tos = RT_TOS(ip_hdr(skb)->tos), | |
306 | .flowi4_scope = scope, | |
307 | .flowi4_mark = vmark ? skb->mark : 0, | |
308 | }; | |
309 | if (!fib_lookup(net, &fl4, &res, 0)) | |
310 | return fib_result_prefsrc(net, &res); | |
311 | } else { | |
312 | scope = RT_SCOPE_LINK; | |
313 | } | |
314 | ||
315 | return inet_select_addr(dev, ip_hdr(skb)->saddr, scope); | |
316 | } | |
317 | ||
318 | bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev) | |
319 | { | |
320 | bool dev_match = false; | |
321 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
322 | int ret; | |
323 | ||
324 | for (ret = 0; ret < fi->fib_nhs; ret++) { | |
325 | struct fib_nh *nh = &fi->fib_nh[ret]; | |
326 | ||
327 | if (nh->fib_nh_dev == dev) { | |
328 | dev_match = true; | |
329 | break; | |
330 | } else if (l3mdev_master_ifindex_rcu(nh->fib_nh_dev) == dev->ifindex) { | |
331 | dev_match = true; | |
332 | break; | |
333 | } | |
334 | } | |
335 | #else | |
336 | if (fi->fib_nh[0].fib_nh_dev == dev) | |
337 | dev_match = true; | |
338 | #endif | |
339 | ||
340 | return dev_match; | |
341 | } | |
342 | EXPORT_SYMBOL_GPL(fib_info_nh_uses_dev); | |
343 | ||
344 | /* Given (packet source, input interface) and optional (dst, oif, tos): | |
345 | * - (main) check, that source is valid i.e. not broadcast or our local | |
346 | * address. | |
347 | * - figure out what "logical" interface this packet arrived | |
348 | * and calculate "specific destination" address. | |
349 | * - check, that packet arrived from expected physical interface. | |
350 | * called with rcu_read_lock() | |
351 | */ | |
352 | static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, | |
353 | u8 tos, int oif, struct net_device *dev, | |
354 | int rpf, struct in_device *idev, u32 *itag) | |
355 | { | |
356 | struct net *net = dev_net(dev); | |
357 | struct flow_keys flkeys; | |
358 | int ret, no_addr; | |
359 | struct fib_result res; | |
360 | struct flowi4 fl4; | |
361 | bool dev_match; | |
362 | ||
363 | fl4.flowi4_oif = 0; | |
364 | fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev); | |
365 | if (!fl4.flowi4_iif) | |
366 | fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX; | |
367 | fl4.daddr = src; | |
368 | fl4.saddr = dst; | |
369 | fl4.flowi4_tos = tos; | |
370 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
371 | fl4.flowi4_tun_key.tun_id = 0; | |
372 | fl4.flowi4_flags = 0; | |
373 | fl4.flowi4_uid = sock_net_uid(net, NULL); | |
374 | ||
375 | no_addr = idev->ifa_list == NULL; | |
376 | ||
377 | fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0; | |
378 | if (!fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys)) { | |
379 | fl4.flowi4_proto = 0; | |
380 | fl4.fl4_sport = 0; | |
381 | fl4.fl4_dport = 0; | |
382 | } | |
383 | ||
384 | if (fib_lookup(net, &fl4, &res, 0)) | |
385 | goto last_resort; | |
386 | if (res.type != RTN_UNICAST && | |
387 | (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev))) | |
388 | goto e_inval; | |
389 | fib_combine_itag(itag, &res); | |
390 | ||
391 | dev_match = fib_info_nh_uses_dev(res.fi, dev); | |
392 | if (dev_match) { | |
393 | ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST; | |
394 | return ret; | |
395 | } | |
396 | if (no_addr) | |
397 | goto last_resort; | |
398 | if (rpf == 1) | |
399 | goto e_rpf; | |
400 | fl4.flowi4_oif = dev->ifindex; | |
401 | ||
402 | ret = 0; | |
403 | if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) { | |
404 | if (res.type == RTN_UNICAST) | |
405 | ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST; | |
406 | } | |
407 | return ret; | |
408 | ||
409 | last_resort: | |
410 | if (rpf) | |
411 | goto e_rpf; | |
412 | *itag = 0; | |
413 | return 0; | |
414 | ||
415 | e_inval: | |
416 | return -EINVAL; | |
417 | e_rpf: | |
418 | return -EXDEV; | |
419 | } | |
420 | ||
421 | /* Ignore rp_filter for packets protected by IPsec. */ | |
422 | int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, | |
423 | u8 tos, int oif, struct net_device *dev, | |
424 | struct in_device *idev, u32 *itag) | |
425 | { | |
426 | int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev); | |
427 | struct net *net = dev_net(dev); | |
428 | ||
429 | if (!r && !fib_num_tclassid_users(net) && | |
430 | (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) { | |
431 | if (IN_DEV_ACCEPT_LOCAL(idev)) | |
432 | goto ok; | |
433 | /* with custom local routes in place, checking local addresses | |
434 | * only will be too optimistic, with custom rules, checking | |
435 | * local addresses only can be too strict, e.g. due to vrf | |
436 | */ | |
437 | if (net->ipv4.fib_has_custom_local_routes || | |
438 | fib4_has_custom_rules(net)) | |
439 | goto full_check; | |
440 | if (inet_lookup_ifaddr_rcu(net, src)) | |
441 | return -EINVAL; | |
442 | ||
443 | ok: | |
444 | *itag = 0; | |
445 | return 0; | |
446 | } | |
447 | ||
448 | full_check: | |
449 | return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag); | |
450 | } | |
451 | ||
452 | static inline __be32 sk_extract_addr(struct sockaddr *addr) | |
453 | { | |
454 | return ((struct sockaddr_in *) addr)->sin_addr.s_addr; | |
455 | } | |
456 | ||
457 | static int put_rtax(struct nlattr *mx, int len, int type, u32 value) | |
458 | { | |
459 | struct nlattr *nla; | |
460 | ||
461 | nla = (struct nlattr *) ((char *) mx + len); | |
462 | nla->nla_type = type; | |
463 | nla->nla_len = nla_attr_size(4); | |
464 | *(u32 *) nla_data(nla) = value; | |
465 | ||
466 | return len + nla_total_size(4); | |
467 | } | |
468 | ||
469 | static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, | |
470 | struct fib_config *cfg) | |
471 | { | |
472 | __be32 addr; | |
473 | int plen; | |
474 | ||
475 | memset(cfg, 0, sizeof(*cfg)); | |
476 | cfg->fc_nlinfo.nl_net = net; | |
477 | ||
478 | if (rt->rt_dst.sa_family != AF_INET) | |
479 | return -EAFNOSUPPORT; | |
480 | ||
481 | /* | |
482 | * Check mask for validity: | |
483 | * a) it must be contiguous. | |
484 | * b) destination must have all host bits clear. | |
485 | * c) if application forgot to set correct family (AF_INET), | |
486 | * reject request unless it is absolutely clear i.e. | |
487 | * both family and mask are zero. | |
488 | */ | |
489 | plen = 32; | |
490 | addr = sk_extract_addr(&rt->rt_dst); | |
491 | if (!(rt->rt_flags & RTF_HOST)) { | |
492 | __be32 mask = sk_extract_addr(&rt->rt_genmask); | |
493 | ||
494 | if (rt->rt_genmask.sa_family != AF_INET) { | |
495 | if (mask || rt->rt_genmask.sa_family) | |
496 | return -EAFNOSUPPORT; | |
497 | } | |
498 | ||
499 | if (bad_mask(mask, addr)) | |
500 | return -EINVAL; | |
501 | ||
502 | plen = inet_mask_len(mask); | |
503 | } | |
504 | ||
505 | cfg->fc_dst_len = plen; | |
506 | cfg->fc_dst = addr; | |
507 | ||
508 | if (cmd != SIOCDELRT) { | |
509 | cfg->fc_nlflags = NLM_F_CREATE; | |
510 | cfg->fc_protocol = RTPROT_BOOT; | |
511 | } | |
512 | ||
513 | if (rt->rt_metric) | |
514 | cfg->fc_priority = rt->rt_metric - 1; | |
515 | ||
516 | if (rt->rt_flags & RTF_REJECT) { | |
517 | cfg->fc_scope = RT_SCOPE_HOST; | |
518 | cfg->fc_type = RTN_UNREACHABLE; | |
519 | return 0; | |
520 | } | |
521 | ||
522 | cfg->fc_scope = RT_SCOPE_NOWHERE; | |
523 | cfg->fc_type = RTN_UNICAST; | |
524 | ||
525 | if (rt->rt_dev) { | |
526 | char *colon; | |
527 | struct net_device *dev; | |
528 | char devname[IFNAMSIZ]; | |
529 | ||
530 | if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) | |
531 | return -EFAULT; | |
532 | ||
533 | devname[IFNAMSIZ-1] = 0; | |
534 | colon = strchr(devname, ':'); | |
535 | if (colon) | |
536 | *colon = 0; | |
537 | dev = __dev_get_by_name(net, devname); | |
538 | if (!dev) | |
539 | return -ENODEV; | |
540 | cfg->fc_oif = dev->ifindex; | |
541 | cfg->fc_table = l3mdev_fib_table(dev); | |
542 | if (colon) { | |
543 | struct in_ifaddr *ifa; | |
544 | struct in_device *in_dev = __in_dev_get_rtnl(dev); | |
545 | if (!in_dev) | |
546 | return -ENODEV; | |
547 | *colon = ':'; | |
548 | for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) | |
549 | if (strcmp(ifa->ifa_label, devname) == 0) | |
550 | break; | |
551 | if (!ifa) | |
552 | return -ENODEV; | |
553 | cfg->fc_prefsrc = ifa->ifa_local; | |
554 | } | |
555 | } | |
556 | ||
557 | addr = sk_extract_addr(&rt->rt_gateway); | |
558 | if (rt->rt_gateway.sa_family == AF_INET && addr) { | |
559 | unsigned int addr_type; | |
560 | ||
561 | cfg->fc_gw4 = addr; | |
562 | cfg->fc_gw_family = AF_INET; | |
563 | addr_type = inet_addr_type_table(net, addr, cfg->fc_table); | |
564 | if (rt->rt_flags & RTF_GATEWAY && | |
565 | addr_type == RTN_UNICAST) | |
566 | cfg->fc_scope = RT_SCOPE_UNIVERSE; | |
567 | } | |
568 | ||
569 | if (cmd == SIOCDELRT) | |
570 | return 0; | |
571 | ||
572 | if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw_family) | |
573 | return -EINVAL; | |
574 | ||
575 | if (cfg->fc_scope == RT_SCOPE_NOWHERE) | |
576 | cfg->fc_scope = RT_SCOPE_LINK; | |
577 | ||
578 | if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { | |
579 | struct nlattr *mx; | |
580 | int len = 0; | |
581 | ||
582 | mx = kcalloc(3, nla_total_size(4), GFP_KERNEL); | |
583 | if (!mx) | |
584 | return -ENOMEM; | |
585 | ||
586 | if (rt->rt_flags & RTF_MTU) | |
587 | len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); | |
588 | ||
589 | if (rt->rt_flags & RTF_WINDOW) | |
590 | len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); | |
591 | ||
592 | if (rt->rt_flags & RTF_IRTT) | |
593 | len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); | |
594 | ||
595 | cfg->fc_mx = mx; | |
596 | cfg->fc_mx_len = len; | |
597 | } | |
598 | ||
599 | return 0; | |
600 | } | |
601 | ||
602 | /* | |
603 | * Handle IP routing ioctl calls. | |
604 | * These are used to manipulate the routing tables | |
605 | */ | |
606 | int ip_rt_ioctl(struct net *net, unsigned int cmd, struct rtentry *rt) | |
607 | { | |
608 | struct fib_config cfg; | |
609 | int err; | |
610 | ||
611 | switch (cmd) { | |
612 | case SIOCADDRT: /* Add a route */ | |
613 | case SIOCDELRT: /* Delete a route */ | |
614 | if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) | |
615 | return -EPERM; | |
616 | ||
617 | rtnl_lock(); | |
618 | err = rtentry_to_fib_config(net, cmd, rt, &cfg); | |
619 | if (err == 0) { | |
620 | struct fib_table *tb; | |
621 | ||
622 | if (cmd == SIOCDELRT) { | |
623 | tb = fib_get_table(net, cfg.fc_table); | |
624 | if (tb) | |
625 | err = fib_table_delete(net, tb, &cfg, | |
626 | NULL); | |
627 | else | |
628 | err = -ESRCH; | |
629 | } else { | |
630 | tb = fib_new_table(net, cfg.fc_table); | |
631 | if (tb) | |
632 | err = fib_table_insert(net, tb, | |
633 | &cfg, NULL); | |
634 | else | |
635 | err = -ENOBUFS; | |
636 | } | |
637 | ||
638 | /* allocated by rtentry_to_fib_config() */ | |
639 | kfree(cfg.fc_mx); | |
640 | } | |
641 | rtnl_unlock(); | |
642 | return err; | |
643 | } | |
644 | return -EINVAL; | |
645 | } | |
646 | ||
647 | const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { | |
648 | [RTA_DST] = { .type = NLA_U32 }, | |
649 | [RTA_SRC] = { .type = NLA_U32 }, | |
650 | [RTA_IIF] = { .type = NLA_U32 }, | |
651 | [RTA_OIF] = { .type = NLA_U32 }, | |
652 | [RTA_GATEWAY] = { .type = NLA_U32 }, | |
653 | [RTA_PRIORITY] = { .type = NLA_U32 }, | |
654 | [RTA_PREFSRC] = { .type = NLA_U32 }, | |
655 | [RTA_METRICS] = { .type = NLA_NESTED }, | |
656 | [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, | |
657 | [RTA_FLOW] = { .type = NLA_U32 }, | |
658 | [RTA_ENCAP_TYPE] = { .type = NLA_U16 }, | |
659 | [RTA_ENCAP] = { .type = NLA_NESTED }, | |
660 | [RTA_UID] = { .type = NLA_U32 }, | |
661 | [RTA_MARK] = { .type = NLA_U32 }, | |
662 | [RTA_TABLE] = { .type = NLA_U32 }, | |
663 | [RTA_IP_PROTO] = { .type = NLA_U8 }, | |
664 | [RTA_SPORT] = { .type = NLA_U16 }, | |
665 | [RTA_DPORT] = { .type = NLA_U16 }, | |
666 | }; | |
667 | ||
668 | int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla, | |
669 | struct netlink_ext_ack *extack) | |
670 | { | |
671 | struct rtvia *via; | |
672 | int alen; | |
673 | ||
674 | if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) { | |
675 | NL_SET_ERR_MSG(extack, "Invalid attribute length for RTA_VIA"); | |
676 | return -EINVAL; | |
677 | } | |
678 | ||
679 | via = nla_data(nla); | |
680 | alen = nla_len(nla) - offsetof(struct rtvia, rtvia_addr); | |
681 | ||
682 | switch (via->rtvia_family) { | |
683 | case AF_INET: | |
684 | if (alen != sizeof(__be32)) { | |
685 | NL_SET_ERR_MSG(extack, "Invalid IPv4 address in RTA_VIA"); | |
686 | return -EINVAL; | |
687 | } | |
688 | cfg->fc_gw_family = AF_INET; | |
689 | cfg->fc_gw4 = *((__be32 *)via->rtvia_addr); | |
690 | break; | |
691 | case AF_INET6: | |
692 | #ifdef CONFIG_IPV6 | |
693 | if (alen != sizeof(struct in6_addr)) { | |
694 | NL_SET_ERR_MSG(extack, "Invalid IPv6 address in RTA_VIA"); | |
695 | return -EINVAL; | |
696 | } | |
697 | cfg->fc_gw_family = AF_INET6; | |
698 | cfg->fc_gw6 = *((struct in6_addr *)via->rtvia_addr); | |
699 | #else | |
700 | NL_SET_ERR_MSG(extack, "IPv6 support not enabled in kernel"); | |
701 | return -EINVAL; | |
702 | #endif | |
703 | break; | |
704 | default: | |
705 | NL_SET_ERR_MSG(extack, "Unsupported address family in RTA_VIA"); | |
706 | return -EINVAL; | |
707 | } | |
708 | ||
709 | return 0; | |
710 | } | |
711 | ||
712 | static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, | |
713 | struct nlmsghdr *nlh, struct fib_config *cfg, | |
714 | struct netlink_ext_ack *extack) | |
715 | { | |
716 | bool has_gw = false, has_via = false; | |
717 | struct nlattr *attr; | |
718 | int err, remaining; | |
719 | struct rtmsg *rtm; | |
720 | ||
721 | err = nlmsg_validate_deprecated(nlh, sizeof(*rtm), RTA_MAX, | |
722 | rtm_ipv4_policy, extack); | |
723 | if (err < 0) | |
724 | goto errout; | |
725 | ||
726 | memset(cfg, 0, sizeof(*cfg)); | |
727 | ||
728 | rtm = nlmsg_data(nlh); | |
729 | cfg->fc_dst_len = rtm->rtm_dst_len; | |
730 | cfg->fc_tos = rtm->rtm_tos; | |
731 | cfg->fc_table = rtm->rtm_table; | |
732 | cfg->fc_protocol = rtm->rtm_protocol; | |
733 | cfg->fc_scope = rtm->rtm_scope; | |
734 | cfg->fc_type = rtm->rtm_type; | |
735 | cfg->fc_flags = rtm->rtm_flags; | |
736 | cfg->fc_nlflags = nlh->nlmsg_flags; | |
737 | ||
738 | cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; | |
739 | cfg->fc_nlinfo.nlh = nlh; | |
740 | cfg->fc_nlinfo.nl_net = net; | |
741 | ||
742 | if (cfg->fc_type > RTN_MAX) { | |
743 | NL_SET_ERR_MSG(extack, "Invalid route type"); | |
744 | err = -EINVAL; | |
745 | goto errout; | |
746 | } | |
747 | ||
748 | nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { | |
749 | switch (nla_type(attr)) { | |
750 | case RTA_DST: | |
751 | cfg->fc_dst = nla_get_be32(attr); | |
752 | break; | |
753 | case RTA_OIF: | |
754 | cfg->fc_oif = nla_get_u32(attr); | |
755 | break; | |
756 | case RTA_GATEWAY: | |
757 | has_gw = true; | |
758 | cfg->fc_gw4 = nla_get_be32(attr); | |
759 | if (cfg->fc_gw4) | |
760 | cfg->fc_gw_family = AF_INET; | |
761 | break; | |
762 | case RTA_VIA: | |
763 | has_via = true; | |
764 | err = fib_gw_from_via(cfg, attr, extack); | |
765 | if (err) | |
766 | goto errout; | |
767 | break; | |
768 | case RTA_PRIORITY: | |
769 | cfg->fc_priority = nla_get_u32(attr); | |
770 | break; | |
771 | case RTA_PREFSRC: | |
772 | cfg->fc_prefsrc = nla_get_be32(attr); | |
773 | break; | |
774 | case RTA_METRICS: | |
775 | cfg->fc_mx = nla_data(attr); | |
776 | cfg->fc_mx_len = nla_len(attr); | |
777 | break; | |
778 | case RTA_MULTIPATH: | |
779 | err = lwtunnel_valid_encap_type_attr(nla_data(attr), | |
780 | nla_len(attr), | |
781 | extack); | |
782 | if (err < 0) | |
783 | goto errout; | |
784 | cfg->fc_mp = nla_data(attr); | |
785 | cfg->fc_mp_len = nla_len(attr); | |
786 | break; | |
787 | case RTA_FLOW: | |
788 | cfg->fc_flow = nla_get_u32(attr); | |
789 | break; | |
790 | case RTA_TABLE: | |
791 | cfg->fc_table = nla_get_u32(attr); | |
792 | break; | |
793 | case RTA_ENCAP: | |
794 | cfg->fc_encap = attr; | |
795 | break; | |
796 | case RTA_ENCAP_TYPE: | |
797 | cfg->fc_encap_type = nla_get_u16(attr); | |
798 | err = lwtunnel_valid_encap_type(cfg->fc_encap_type, | |
799 | extack); | |
800 | if (err < 0) | |
801 | goto errout; | |
802 | break; | |
803 | } | |
804 | } | |
805 | ||
806 | if (has_gw && has_via) { | |
807 | NL_SET_ERR_MSG(extack, | |
808 | "Nexthop configuration can not contain both GATEWAY and VIA"); | |
809 | goto errout; | |
810 | } | |
811 | ||
812 | return 0; | |
813 | errout: | |
814 | return err; | |
815 | } | |
816 | ||
817 | static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, | |
818 | struct netlink_ext_ack *extack) | |
819 | { | |
820 | struct net *net = sock_net(skb->sk); | |
821 | struct fib_config cfg; | |
822 | struct fib_table *tb; | |
823 | int err; | |
824 | ||
825 | err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); | |
826 | if (err < 0) | |
827 | goto errout; | |
828 | ||
829 | tb = fib_get_table(net, cfg.fc_table); | |
830 | if (!tb) { | |
831 | NL_SET_ERR_MSG(extack, "FIB table does not exist"); | |
832 | err = -ESRCH; | |
833 | goto errout; | |
834 | } | |
835 | ||
836 | err = fib_table_delete(net, tb, &cfg, extack); | |
837 | errout: | |
838 | return err; | |
839 | } | |
840 | ||
841 | static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, | |
842 | struct netlink_ext_ack *extack) | |
843 | { | |
844 | struct net *net = sock_net(skb->sk); | |
845 | struct fib_config cfg; | |
846 | struct fib_table *tb; | |
847 | int err; | |
848 | ||
849 | err = rtm_to_fib_config(net, skb, nlh, &cfg, extack); | |
850 | if (err < 0) | |
851 | goto errout; | |
852 | ||
853 | tb = fib_new_table(net, cfg.fc_table); | |
854 | if (!tb) { | |
855 | err = -ENOBUFS; | |
856 | goto errout; | |
857 | } | |
858 | ||
859 | err = fib_table_insert(net, tb, &cfg, extack); | |
860 | if (!err && cfg.fc_type == RTN_LOCAL) | |
861 | net->ipv4.fib_has_custom_local_routes = true; | |
862 | errout: | |
863 | return err; | |
864 | } | |
865 | ||
866 | int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh, | |
867 | struct fib_dump_filter *filter, | |
868 | struct netlink_callback *cb) | |
869 | { | |
870 | struct netlink_ext_ack *extack = cb->extack; | |
871 | struct nlattr *tb[RTA_MAX + 1]; | |
872 | struct rtmsg *rtm; | |
873 | int err, i; | |
874 | ||
875 | ASSERT_RTNL(); | |
876 | ||
877 | if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) { | |
878 | NL_SET_ERR_MSG(extack, "Invalid header for FIB dump request"); | |
879 | return -EINVAL; | |
880 | } | |
881 | ||
882 | rtm = nlmsg_data(nlh); | |
883 | if (rtm->rtm_dst_len || rtm->rtm_src_len || rtm->rtm_tos || | |
884 | rtm->rtm_scope) { | |
885 | NL_SET_ERR_MSG(extack, "Invalid values in header for FIB dump request"); | |
886 | return -EINVAL; | |
887 | } | |
888 | if (rtm->rtm_flags & ~(RTM_F_CLONED | RTM_F_PREFIX)) { | |
889 | NL_SET_ERR_MSG(extack, "Invalid flags for FIB dump request"); | |
890 | return -EINVAL; | |
891 | } | |
892 | ||
893 | filter->dump_all_families = (rtm->rtm_family == AF_UNSPEC); | |
894 | filter->flags = rtm->rtm_flags; | |
895 | filter->protocol = rtm->rtm_protocol; | |
896 | filter->rt_type = rtm->rtm_type; | |
897 | filter->table_id = rtm->rtm_table; | |
898 | ||
899 | err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, | |
900 | rtm_ipv4_policy, extack); | |
901 | if (err < 0) | |
902 | return err; | |
903 | ||
904 | for (i = 0; i <= RTA_MAX; ++i) { | |
905 | int ifindex; | |
906 | ||
907 | if (!tb[i]) | |
908 | continue; | |
909 | ||
910 | switch (i) { | |
911 | case RTA_TABLE: | |
912 | filter->table_id = nla_get_u32(tb[i]); | |
913 | break; | |
914 | case RTA_OIF: | |
915 | ifindex = nla_get_u32(tb[i]); | |
916 | filter->dev = __dev_get_by_index(net, ifindex); | |
917 | if (!filter->dev) | |
918 | return -ENODEV; | |
919 | break; | |
920 | default: | |
921 | NL_SET_ERR_MSG(extack, "Unsupported attribute in dump request"); | |
922 | return -EINVAL; | |
923 | } | |
924 | } | |
925 | ||
926 | if (filter->flags || filter->protocol || filter->rt_type || | |
927 | filter->table_id || filter->dev) { | |
928 | filter->filter_set = 1; | |
929 | cb->answer_flags = NLM_F_DUMP_FILTERED; | |
930 | } | |
931 | ||
932 | return 0; | |
933 | } | |
934 | EXPORT_SYMBOL_GPL(ip_valid_fib_dump_req); | |
935 | ||
936 | static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) | |
937 | { | |
938 | const struct nlmsghdr *nlh = cb->nlh; | |
939 | struct net *net = sock_net(skb->sk); | |
940 | struct fib_dump_filter filter = {}; | |
941 | unsigned int h, s_h; | |
942 | unsigned int e = 0, s_e; | |
943 | struct fib_table *tb; | |
944 | struct hlist_head *head; | |
945 | int dumped = 0, err; | |
946 | ||
947 | if (cb->strict_check) { | |
948 | err = ip_valid_fib_dump_req(net, nlh, &filter, cb); | |
949 | if (err < 0) | |
950 | return err; | |
951 | } else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) { | |
952 | struct rtmsg *rtm = nlmsg_data(nlh); | |
953 | ||
954 | filter.flags = rtm->rtm_flags & (RTM_F_PREFIX | RTM_F_CLONED); | |
955 | } | |
956 | ||
957 | /* fib entries are never clones and ipv4 does not use prefix flag */ | |
958 | if (filter.flags & (RTM_F_PREFIX | RTM_F_CLONED)) | |
959 | return skb->len; | |
960 | ||
961 | if (filter.table_id) { | |
962 | tb = fib_get_table(net, filter.table_id); | |
963 | if (!tb) { | |
964 | if (filter.dump_all_families) | |
965 | return skb->len; | |
966 | ||
967 | NL_SET_ERR_MSG(cb->extack, "ipv4: FIB table does not exist"); | |
968 | return -ENOENT; | |
969 | } | |
970 | ||
971 | err = fib_table_dump(tb, skb, cb, &filter); | |
972 | return skb->len ? : err; | |
973 | } | |
974 | ||
975 | s_h = cb->args[0]; | |
976 | s_e = cb->args[1]; | |
977 | ||
978 | rcu_read_lock(); | |
979 | ||
980 | for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { | |
981 | e = 0; | |
982 | head = &net->ipv4.fib_table_hash[h]; | |
983 | hlist_for_each_entry_rcu(tb, head, tb_hlist) { | |
984 | if (e < s_e) | |
985 | goto next; | |
986 | if (dumped) | |
987 | memset(&cb->args[2], 0, sizeof(cb->args) - | |
988 | 2 * sizeof(cb->args[0])); | |
989 | err = fib_table_dump(tb, skb, cb, &filter); | |
990 | if (err < 0) { | |
991 | if (likely(skb->len)) | |
992 | goto out; | |
993 | ||
994 | goto out_err; | |
995 | } | |
996 | dumped = 1; | |
997 | next: | |
998 | e++; | |
999 | } | |
1000 | } | |
1001 | out: | |
1002 | err = skb->len; | |
1003 | out_err: | |
1004 | rcu_read_unlock(); | |
1005 | ||
1006 | cb->args[1] = e; | |
1007 | cb->args[0] = h; | |
1008 | ||
1009 | return err; | |
1010 | } | |
1011 | ||
1012 | /* Prepare and feed intra-kernel routing request. | |
1013 | * Really, it should be netlink message, but :-( netlink | |
1014 | * can be not configured, so that we feed it directly | |
1015 | * to fib engine. It is legal, because all events occur | |
1016 | * only when netlink is already locked. | |
1017 | */ | |
1018 | static void fib_magic(int cmd, int type, __be32 dst, int dst_len, | |
1019 | struct in_ifaddr *ifa, u32 rt_priority) | |
1020 | { | |
1021 | struct net *net = dev_net(ifa->ifa_dev->dev); | |
1022 | u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev); | |
1023 | struct fib_table *tb; | |
1024 | struct fib_config cfg = { | |
1025 | .fc_protocol = RTPROT_KERNEL, | |
1026 | .fc_type = type, | |
1027 | .fc_dst = dst, | |
1028 | .fc_dst_len = dst_len, | |
1029 | .fc_priority = rt_priority, | |
1030 | .fc_prefsrc = ifa->ifa_local, | |
1031 | .fc_oif = ifa->ifa_dev->dev->ifindex, | |
1032 | .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, | |
1033 | .fc_nlinfo = { | |
1034 | .nl_net = net, | |
1035 | }, | |
1036 | }; | |
1037 | ||
1038 | if (!tb_id) | |
1039 | tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL; | |
1040 | ||
1041 | tb = fib_new_table(net, tb_id); | |
1042 | if (!tb) | |
1043 | return; | |
1044 | ||
1045 | cfg.fc_table = tb->tb_id; | |
1046 | ||
1047 | if (type != RTN_LOCAL) | |
1048 | cfg.fc_scope = RT_SCOPE_LINK; | |
1049 | else | |
1050 | cfg.fc_scope = RT_SCOPE_HOST; | |
1051 | ||
1052 | if (cmd == RTM_NEWROUTE) | |
1053 | fib_table_insert(net, tb, &cfg, NULL); | |
1054 | else | |
1055 | fib_table_delete(net, tb, &cfg, NULL); | |
1056 | } | |
1057 | ||
1058 | void fib_add_ifaddr(struct in_ifaddr *ifa) | |
1059 | { | |
1060 | struct in_device *in_dev = ifa->ifa_dev; | |
1061 | struct net_device *dev = in_dev->dev; | |
1062 | struct in_ifaddr *prim = ifa; | |
1063 | __be32 mask = ifa->ifa_mask; | |
1064 | __be32 addr = ifa->ifa_local; | |
1065 | __be32 prefix = ifa->ifa_address & mask; | |
1066 | ||
1067 | if (ifa->ifa_flags & IFA_F_SECONDARY) { | |
1068 | prim = inet_ifa_byprefix(in_dev, prefix, mask); | |
1069 | if (!prim) { | |
1070 | pr_warn("%s: bug: prim == NULL\n", __func__); | |
1071 | return; | |
1072 | } | |
1073 | } | |
1074 | ||
1075 | fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim, 0); | |
1076 | ||
1077 | if (!(dev->flags & IFF_UP)) | |
1078 | return; | |
1079 | ||
1080 | /* Add broadcast address, if it is explicitly assigned. */ | |
1081 | if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) | |
1082 | fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, | |
1083 | prim, 0); | |
1084 | ||
1085 | if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && | |
1086 | (prefix != addr || ifa->ifa_prefixlen < 32)) { | |
1087 | if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) | |
1088 | fib_magic(RTM_NEWROUTE, | |
1089 | dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, | |
1090 | prefix, ifa->ifa_prefixlen, prim, | |
1091 | ifa->ifa_rt_priority); | |
1092 | ||
1093 | /* Add network specific broadcasts, when it takes a sense */ | |
1094 | if (ifa->ifa_prefixlen < 31) { | |
1095 | fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, | |
1096 | prim, 0); | |
1097 | fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask, | |
1098 | 32, prim, 0); | |
1099 | } | |
1100 | } | |
1101 | } | |
1102 | ||
1103 | void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric) | |
1104 | { | |
1105 | __be32 prefix = ifa->ifa_address & ifa->ifa_mask; | |
1106 | struct in_device *in_dev = ifa->ifa_dev; | |
1107 | struct net_device *dev = in_dev->dev; | |
1108 | ||
1109 | if (!(dev->flags & IFF_UP) || | |
1110 | ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || | |
1111 | ipv4_is_zeronet(prefix) || | |
1112 | prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32) | |
1113 | return; | |
1114 | ||
1115 | /* add the new */ | |
1116 | fib_magic(RTM_NEWROUTE, | |
1117 | dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, | |
1118 | prefix, ifa->ifa_prefixlen, ifa, new_metric); | |
1119 | ||
1120 | /* delete the old */ | |
1121 | fib_magic(RTM_DELROUTE, | |
1122 | dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, | |
1123 | prefix, ifa->ifa_prefixlen, ifa, ifa->ifa_rt_priority); | |
1124 | } | |
1125 | ||
1126 | /* Delete primary or secondary address. | |
1127 | * Optionally, on secondary address promotion consider the addresses | |
1128 | * from subnet iprim as deleted, even if they are in device list. | |
1129 | * In this case the secondary ifa can be in device list. | |
1130 | */ | |
1131 | void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) | |
1132 | { | |
1133 | struct in_device *in_dev = ifa->ifa_dev; | |
1134 | struct net_device *dev = in_dev->dev; | |
1135 | struct in_ifaddr *ifa1; | |
1136 | struct in_ifaddr *prim = ifa, *prim1 = NULL; | |
1137 | __be32 brd = ifa->ifa_address | ~ifa->ifa_mask; | |
1138 | __be32 any = ifa->ifa_address & ifa->ifa_mask; | |
1139 | #define LOCAL_OK 1 | |
1140 | #define BRD_OK 2 | |
1141 | #define BRD0_OK 4 | |
1142 | #define BRD1_OK 8 | |
1143 | unsigned int ok = 0; | |
1144 | int subnet = 0; /* Primary network */ | |
1145 | int gone = 1; /* Address is missing */ | |
1146 | int same_prefsrc = 0; /* Another primary with same IP */ | |
1147 | ||
1148 | if (ifa->ifa_flags & IFA_F_SECONDARY) { | |
1149 | prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); | |
1150 | if (!prim) { | |
1151 | /* if the device has been deleted, we don't perform | |
1152 | * address promotion | |
1153 | */ | |
1154 | if (!in_dev->dead) | |
1155 | pr_warn("%s: bug: prim == NULL\n", __func__); | |
1156 | return; | |
1157 | } | |
1158 | if (iprim && iprim != prim) { | |
1159 | pr_warn("%s: bug: iprim != prim\n", __func__); | |
1160 | return; | |
1161 | } | |
1162 | } else if (!ipv4_is_zeronet(any) && | |
1163 | (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) { | |
1164 | if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) | |
1165 | fib_magic(RTM_DELROUTE, | |
1166 | dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, | |
1167 | any, ifa->ifa_prefixlen, prim, 0); | |
1168 | subnet = 1; | |
1169 | } | |
1170 | ||
1171 | if (in_dev->dead) | |
1172 | goto no_promotions; | |
1173 | ||
1174 | /* Deletion is more complicated than add. | |
1175 | * We should take care of not to delete too much :-) | |
1176 | * | |
1177 | * Scan address list to be sure that addresses are really gone. | |
1178 | */ | |
1179 | ||
1180 | for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) { | |
1181 | if (ifa1 == ifa) { | |
1182 | /* promotion, keep the IP */ | |
1183 | gone = 0; | |
1184 | continue; | |
1185 | } | |
1186 | /* Ignore IFAs from our subnet */ | |
1187 | if (iprim && ifa1->ifa_mask == iprim->ifa_mask && | |
1188 | inet_ifa_match(ifa1->ifa_address, iprim)) | |
1189 | continue; | |
1190 | ||
1191 | /* Ignore ifa1 if it uses different primary IP (prefsrc) */ | |
1192 | if (ifa1->ifa_flags & IFA_F_SECONDARY) { | |
1193 | /* Another address from our subnet? */ | |
1194 | if (ifa1->ifa_mask == prim->ifa_mask && | |
1195 | inet_ifa_match(ifa1->ifa_address, prim)) | |
1196 | prim1 = prim; | |
1197 | else { | |
1198 | /* We reached the secondaries, so | |
1199 | * same_prefsrc should be determined. | |
1200 | */ | |
1201 | if (!same_prefsrc) | |
1202 | continue; | |
1203 | /* Search new prim1 if ifa1 is not | |
1204 | * using the current prim1 | |
1205 | */ | |
1206 | if (!prim1 || | |
1207 | ifa1->ifa_mask != prim1->ifa_mask || | |
1208 | !inet_ifa_match(ifa1->ifa_address, prim1)) | |
1209 | prim1 = inet_ifa_byprefix(in_dev, | |
1210 | ifa1->ifa_address, | |
1211 | ifa1->ifa_mask); | |
1212 | if (!prim1) | |
1213 | continue; | |
1214 | if (prim1->ifa_local != prim->ifa_local) | |
1215 | continue; | |
1216 | } | |
1217 | } else { | |
1218 | if (prim->ifa_local != ifa1->ifa_local) | |
1219 | continue; | |
1220 | prim1 = ifa1; | |
1221 | if (prim != prim1) | |
1222 | same_prefsrc = 1; | |
1223 | } | |
1224 | if (ifa->ifa_local == ifa1->ifa_local) | |
1225 | ok |= LOCAL_OK; | |
1226 | if (ifa->ifa_broadcast == ifa1->ifa_broadcast) | |
1227 | ok |= BRD_OK; | |
1228 | if (brd == ifa1->ifa_broadcast) | |
1229 | ok |= BRD1_OK; | |
1230 | if (any == ifa1->ifa_broadcast) | |
1231 | ok |= BRD0_OK; | |
1232 | /* primary has network specific broadcasts */ | |
1233 | if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) { | |
1234 | __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask; | |
1235 | __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask; | |
1236 | ||
1237 | if (!ipv4_is_zeronet(any1)) { | |
1238 | if (ifa->ifa_broadcast == brd1 || | |
1239 | ifa->ifa_broadcast == any1) | |
1240 | ok |= BRD_OK; | |
1241 | if (brd == brd1 || brd == any1) | |
1242 | ok |= BRD1_OK; | |
1243 | if (any == brd1 || any == any1) | |
1244 | ok |= BRD0_OK; | |
1245 | } | |
1246 | } | |
1247 | } | |
1248 | ||
1249 | no_promotions: | |
1250 | if (!(ok & BRD_OK)) | |
1251 | fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, | |
1252 | prim, 0); | |
1253 | if (subnet && ifa->ifa_prefixlen < 31) { | |
1254 | if (!(ok & BRD1_OK)) | |
1255 | fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, | |
1256 | prim, 0); | |
1257 | if (!(ok & BRD0_OK)) | |
1258 | fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, | |
1259 | prim, 0); | |
1260 | } | |
1261 | if (!(ok & LOCAL_OK)) { | |
1262 | unsigned int addr_type; | |
1263 | ||
1264 | fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim, 0); | |
1265 | ||
1266 | /* Check, that this local address finally disappeared. */ | |
1267 | addr_type = inet_addr_type_dev_table(dev_net(dev), dev, | |
1268 | ifa->ifa_local); | |
1269 | if (gone && addr_type != RTN_LOCAL) { | |
1270 | /* And the last, but not the least thing. | |
1271 | * We must flush stray FIB entries. | |
1272 | * | |
1273 | * First of all, we scan fib_info list searching | |
1274 | * for stray nexthop entries, then ignite fib_flush. | |
1275 | */ | |
1276 | if (fib_sync_down_addr(dev, ifa->ifa_local)) | |
1277 | fib_flush(dev_net(dev)); | |
1278 | } | |
1279 | } | |
1280 | #undef LOCAL_OK | |
1281 | #undef BRD_OK | |
1282 | #undef BRD0_OK | |
1283 | #undef BRD1_OK | |
1284 | } | |
1285 | ||
1286 | static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn) | |
1287 | { | |
1288 | ||
1289 | struct fib_result res; | |
1290 | struct flowi4 fl4 = { | |
1291 | .flowi4_mark = frn->fl_mark, | |
1292 | .daddr = frn->fl_addr, | |
1293 | .flowi4_tos = frn->fl_tos, | |
1294 | .flowi4_scope = frn->fl_scope, | |
1295 | }; | |
1296 | struct fib_table *tb; | |
1297 | ||
1298 | rcu_read_lock(); | |
1299 | ||
1300 | tb = fib_get_table(net, frn->tb_id_in); | |
1301 | ||
1302 | frn->err = -ENOENT; | |
1303 | if (tb) { | |
1304 | local_bh_disable(); | |
1305 | ||
1306 | frn->tb_id = tb->tb_id; | |
1307 | frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); | |
1308 | ||
1309 | if (!frn->err) { | |
1310 | frn->prefixlen = res.prefixlen; | |
1311 | frn->nh_sel = res.nh_sel; | |
1312 | frn->type = res.type; | |
1313 | frn->scope = res.scope; | |
1314 | } | |
1315 | local_bh_enable(); | |
1316 | } | |
1317 | ||
1318 | rcu_read_unlock(); | |
1319 | } | |
1320 | ||
1321 | static void nl_fib_input(struct sk_buff *skb) | |
1322 | { | |
1323 | struct net *net; | |
1324 | struct fib_result_nl *frn; | |
1325 | struct nlmsghdr *nlh; | |
1326 | u32 portid; | |
1327 | ||
1328 | net = sock_net(skb->sk); | |
1329 | nlh = nlmsg_hdr(skb); | |
1330 | if (skb->len < nlmsg_total_size(sizeof(*frn)) || | |
1331 | skb->len < nlh->nlmsg_len || | |
1332 | nlmsg_len(nlh) < sizeof(*frn)) | |
1333 | return; | |
1334 | ||
1335 | skb = netlink_skb_clone(skb, GFP_KERNEL); | |
1336 | if (!skb) | |
1337 | return; | |
1338 | nlh = nlmsg_hdr(skb); | |
1339 | ||
1340 | frn = (struct fib_result_nl *) nlmsg_data(nlh); | |
1341 | nl_fib_lookup(net, frn); | |
1342 | ||
1343 | portid = NETLINK_CB(skb).portid; /* netlink portid */ | |
1344 | NETLINK_CB(skb).portid = 0; /* from kernel */ | |
1345 | NETLINK_CB(skb).dst_group = 0; /* unicast */ | |
1346 | netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT); | |
1347 | } | |
1348 | ||
1349 | static int __net_init nl_fib_lookup_init(struct net *net) | |
1350 | { | |
1351 | struct sock *sk; | |
1352 | struct netlink_kernel_cfg cfg = { | |
1353 | .input = nl_fib_input, | |
1354 | }; | |
1355 | ||
1356 | sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg); | |
1357 | if (!sk) | |
1358 | return -EAFNOSUPPORT; | |
1359 | net->ipv4.fibnl = sk; | |
1360 | return 0; | |
1361 | } | |
1362 | ||
1363 | static void nl_fib_lookup_exit(struct net *net) | |
1364 | { | |
1365 | netlink_kernel_release(net->ipv4.fibnl); | |
1366 | net->ipv4.fibnl = NULL; | |
1367 | } | |
1368 | ||
1369 | static void fib_disable_ip(struct net_device *dev, unsigned long event, | |
1370 | bool force) | |
1371 | { | |
1372 | if (fib_sync_down_dev(dev, event, force)) | |
1373 | fib_flush(dev_net(dev)); | |
1374 | else | |
1375 | rt_cache_flush(dev_net(dev)); | |
1376 | arp_ifdown(dev); | |
1377 | } | |
1378 | ||
1379 | static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) | |
1380 | { | |
1381 | struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; | |
1382 | struct net_device *dev = ifa->ifa_dev->dev; | |
1383 | struct net *net = dev_net(dev); | |
1384 | ||
1385 | switch (event) { | |
1386 | case NETDEV_UP: | |
1387 | fib_add_ifaddr(ifa); | |
1388 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
1389 | fib_sync_up(dev, RTNH_F_DEAD); | |
1390 | #endif | |
1391 | atomic_inc(&net->ipv4.dev_addr_genid); | |
1392 | rt_cache_flush(dev_net(dev)); | |
1393 | break; | |
1394 | case NETDEV_DOWN: | |
1395 | fib_del_ifaddr(ifa, NULL); | |
1396 | atomic_inc(&net->ipv4.dev_addr_genid); | |
1397 | if (!ifa->ifa_dev->ifa_list) { | |
1398 | /* Last address was deleted from this interface. | |
1399 | * Disable IP. | |
1400 | */ | |
1401 | fib_disable_ip(dev, event, true); | |
1402 | } else { | |
1403 | rt_cache_flush(dev_net(dev)); | |
1404 | } | |
1405 | break; | |
1406 | } | |
1407 | return NOTIFY_DONE; | |
1408 | } | |
1409 | ||
1410 | static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) | |
1411 | { | |
1412 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); | |
1413 | struct netdev_notifier_changeupper_info *upper_info = ptr; | |
1414 | struct netdev_notifier_info_ext *info_ext = ptr; | |
1415 | struct in_device *in_dev; | |
1416 | struct net *net = dev_net(dev); | |
1417 | unsigned int flags; | |
1418 | ||
1419 | if (event == NETDEV_UNREGISTER) { | |
1420 | fib_disable_ip(dev, event, true); | |
1421 | rt_flush_dev(dev); | |
1422 | return NOTIFY_DONE; | |
1423 | } | |
1424 | ||
1425 | in_dev = __in_dev_get_rtnl(dev); | |
1426 | if (!in_dev) | |
1427 | return NOTIFY_DONE; | |
1428 | ||
1429 | switch (event) { | |
1430 | case NETDEV_UP: | |
1431 | for_ifa(in_dev) { | |
1432 | fib_add_ifaddr(ifa); | |
1433 | } endfor_ifa(in_dev); | |
1434 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
1435 | fib_sync_up(dev, RTNH_F_DEAD); | |
1436 | #endif | |
1437 | atomic_inc(&net->ipv4.dev_addr_genid); | |
1438 | rt_cache_flush(net); | |
1439 | break; | |
1440 | case NETDEV_DOWN: | |
1441 | fib_disable_ip(dev, event, false); | |
1442 | break; | |
1443 | case NETDEV_CHANGE: | |
1444 | flags = dev_get_flags(dev); | |
1445 | if (flags & (IFF_RUNNING | IFF_LOWER_UP)) | |
1446 | fib_sync_up(dev, RTNH_F_LINKDOWN); | |
1447 | else | |
1448 | fib_sync_down_dev(dev, event, false); | |
1449 | rt_cache_flush(net); | |
1450 | break; | |
1451 | case NETDEV_CHANGEMTU: | |
1452 | fib_sync_mtu(dev, info_ext->ext.mtu); | |
1453 | rt_cache_flush(net); | |
1454 | break; | |
1455 | case NETDEV_CHANGEUPPER: | |
1456 | upper_info = ptr; | |
1457 | /* flush all routes if dev is linked to or unlinked from | |
1458 | * an L3 master device (e.g., VRF) | |
1459 | */ | |
1460 | if (upper_info->upper_dev && | |
1461 | netif_is_l3_master(upper_info->upper_dev)) | |
1462 | fib_disable_ip(dev, NETDEV_DOWN, true); | |
1463 | break; | |
1464 | } | |
1465 | return NOTIFY_DONE; | |
1466 | } | |
1467 | ||
1468 | static struct notifier_block fib_inetaddr_notifier = { | |
1469 | .notifier_call = fib_inetaddr_event, | |
1470 | }; | |
1471 | ||
1472 | static struct notifier_block fib_netdev_notifier = { | |
1473 | .notifier_call = fib_netdev_event, | |
1474 | }; | |
1475 | ||
1476 | static int __net_init ip_fib_net_init(struct net *net) | |
1477 | { | |
1478 | int err; | |
1479 | size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ; | |
1480 | ||
1481 | err = fib4_notifier_init(net); | |
1482 | if (err) | |
1483 | return err; | |
1484 | ||
1485 | /* Avoid false sharing : Use at least a full cache line */ | |
1486 | size = max_t(size_t, size, L1_CACHE_BYTES); | |
1487 | ||
1488 | net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL); | |
1489 | if (!net->ipv4.fib_table_hash) { | |
1490 | err = -ENOMEM; | |
1491 | goto err_table_hash_alloc; | |
1492 | } | |
1493 | ||
1494 | err = fib4_rules_init(net); | |
1495 | if (err < 0) | |
1496 | goto err_rules_init; | |
1497 | return 0; | |
1498 | ||
1499 | err_rules_init: | |
1500 | kfree(net->ipv4.fib_table_hash); | |
1501 | err_table_hash_alloc: | |
1502 | fib4_notifier_exit(net); | |
1503 | return err; | |
1504 | } | |
1505 | ||
1506 | static void ip_fib_net_exit(struct net *net) | |
1507 | { | |
1508 | int i; | |
1509 | ||
1510 | rtnl_lock(); | |
1511 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
1512 | RCU_INIT_POINTER(net->ipv4.fib_main, NULL); | |
1513 | RCU_INIT_POINTER(net->ipv4.fib_default, NULL); | |
1514 | #endif | |
1515 | /* Destroy the tables in reverse order to guarantee that the | |
1516 | * local table, ID 255, is destroyed before the main table, ID | |
1517 | * 254. This is necessary as the local table may contain | |
1518 | * references to data contained in the main table. | |
1519 | */ | |
1520 | for (i = FIB_TABLE_HASHSZ - 1; i >= 0; i--) { | |
1521 | struct hlist_head *head = &net->ipv4.fib_table_hash[i]; | |
1522 | struct hlist_node *tmp; | |
1523 | struct fib_table *tb; | |
1524 | ||
1525 | hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) { | |
1526 | hlist_del(&tb->tb_hlist); | |
1527 | fib_table_flush(net, tb, true); | |
1528 | fib_free_table(tb); | |
1529 | } | |
1530 | } | |
1531 | ||
1532 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
1533 | fib4_rules_exit(net); | |
1534 | #endif | |
1535 | rtnl_unlock(); | |
1536 | kfree(net->ipv4.fib_table_hash); | |
1537 | fib4_notifier_exit(net); | |
1538 | } | |
1539 | ||
1540 | static int __net_init fib_net_init(struct net *net) | |
1541 | { | |
1542 | int error; | |
1543 | ||
1544 | #ifdef CONFIG_IP_ROUTE_CLASSID | |
1545 | net->ipv4.fib_num_tclassid_users = 0; | |
1546 | #endif | |
1547 | error = ip_fib_net_init(net); | |
1548 | if (error < 0) | |
1549 | goto out; | |
1550 | error = nl_fib_lookup_init(net); | |
1551 | if (error < 0) | |
1552 | goto out_nlfl; | |
1553 | error = fib_proc_init(net); | |
1554 | if (error < 0) | |
1555 | goto out_proc; | |
1556 | out: | |
1557 | return error; | |
1558 | ||
1559 | out_proc: | |
1560 | nl_fib_lookup_exit(net); | |
1561 | out_nlfl: | |
1562 | ip_fib_net_exit(net); | |
1563 | goto out; | |
1564 | } | |
1565 | ||
1566 | static void __net_exit fib_net_exit(struct net *net) | |
1567 | { | |
1568 | fib_proc_exit(net); | |
1569 | nl_fib_lookup_exit(net); | |
1570 | ip_fib_net_exit(net); | |
1571 | } | |
1572 | ||
1573 | static struct pernet_operations fib_net_ops = { | |
1574 | .init = fib_net_init, | |
1575 | .exit = fib_net_exit, | |
1576 | }; | |
1577 | ||
1578 | void __init ip_fib_init(void) | |
1579 | { | |
1580 | fib_trie_init(); | |
1581 | ||
1582 | register_pernet_subsys(&fib_net_ops); | |
1583 | ||
1584 | register_netdevice_notifier(&fib_netdev_notifier); | |
1585 | register_inetaddr_notifier(&fib_inetaddr_notifier); | |
1586 | ||
1587 | rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, 0); | |
1588 | rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, 0); | |
1589 | rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, 0); | |
1590 | } |