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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 | * Version: $Id: fib_frontend.c,v 1.26 2001/10/31 21:55:54 davem Exp $ | |
9 | * | |
10 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
17 | ||
18 | #include <linux/module.h> | |
19 | #include <asm/uaccess.h> | |
20 | #include <asm/system.h> | |
21 | #include <linux/bitops.h> | |
22 | #include <linux/capability.h> | |
23 | #include <linux/types.h> | |
24 | #include <linux/kernel.h> | |
25 | #include <linux/mm.h> | |
26 | #include <linux/string.h> | |
27 | #include <linux/socket.h> | |
28 | #include <linux/sockios.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/in.h> | |
31 | #include <linux/inet.h> | |
32 | #include <linux/inetdevice.h> | |
33 | #include <linux/netdevice.h> | |
34 | #include <linux/if_addr.h> | |
35 | #include <linux/if_arp.h> | |
36 | #include <linux/skbuff.h> | |
37 | #include <linux/init.h> | |
38 | #include <linux/list.h> | |
39 | ||
40 | #include <net/ip.h> | |
41 | #include <net/protocol.h> | |
42 | #include <net/route.h> | |
43 | #include <net/tcp.h> | |
44 | #include <net/sock.h> | |
45 | #include <net/icmp.h> | |
46 | #include <net/arp.h> | |
47 | #include <net/ip_fib.h> | |
48 | #include <net/rtnetlink.h> | |
49 | ||
50 | #ifndef CONFIG_IP_MULTIPLE_TABLES | |
51 | ||
52 | static int __net_init fib4_rules_init(struct net *net) | |
53 | { | |
54 | struct fib_table *local_table, *main_table; | |
55 | ||
56 | local_table = fib_hash_table(RT_TABLE_LOCAL); | |
57 | if (local_table == NULL) | |
58 | return -ENOMEM; | |
59 | ||
60 | main_table = fib_hash_table(RT_TABLE_MAIN); | |
61 | if (main_table == NULL) | |
62 | goto fail; | |
63 | ||
64 | hlist_add_head_rcu(&local_table->tb_hlist, | |
65 | &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]); | |
66 | hlist_add_head_rcu(&main_table->tb_hlist, | |
67 | &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]); | |
68 | return 0; | |
69 | ||
70 | fail: | |
71 | kfree(local_table); | |
72 | return -ENOMEM; | |
73 | } | |
74 | #else | |
75 | ||
76 | struct fib_table *fib_new_table(struct net *net, u32 id) | |
77 | { | |
78 | struct fib_table *tb; | |
79 | unsigned int h; | |
80 | ||
81 | if (id == 0) | |
82 | id = RT_TABLE_MAIN; | |
83 | tb = fib_get_table(net, id); | |
84 | if (tb) | |
85 | return tb; | |
86 | ||
87 | tb = fib_hash_table(id); | |
88 | if (!tb) | |
89 | return NULL; | |
90 | h = id & (FIB_TABLE_HASHSZ - 1); | |
91 | hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]); | |
92 | return tb; | |
93 | } | |
94 | ||
95 | struct fib_table *fib_get_table(struct net *net, u32 id) | |
96 | { | |
97 | struct fib_table *tb; | |
98 | struct hlist_node *node; | |
99 | struct hlist_head *head; | |
100 | unsigned int h; | |
101 | ||
102 | if (id == 0) | |
103 | id = RT_TABLE_MAIN; | |
104 | h = id & (FIB_TABLE_HASHSZ - 1); | |
105 | ||
106 | rcu_read_lock(); | |
107 | head = &net->ipv4.fib_table_hash[h]; | |
108 | hlist_for_each_entry_rcu(tb, node, head, tb_hlist) { | |
109 | if (tb->tb_id == id) { | |
110 | rcu_read_unlock(); | |
111 | return tb; | |
112 | } | |
113 | } | |
114 | rcu_read_unlock(); | |
115 | return NULL; | |
116 | } | |
117 | #endif /* CONFIG_IP_MULTIPLE_TABLES */ | |
118 | ||
119 | void fib_select_default(const struct flowi *flp, struct fib_result *res) | |
120 | { | |
121 | struct fib_table *tb; | |
122 | int table = RT_TABLE_MAIN; | |
123 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
124 | if (res->r == NULL || res->r->action != FR_ACT_TO_TBL) | |
125 | return; | |
126 | table = res->r->table; | |
127 | #endif | |
128 | tb = fib_get_table(&init_net, table); | |
129 | if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
130 | tb->tb_select_default(tb, flp, res); | |
131 | } | |
132 | ||
133 | static void fib_flush(struct net *net) | |
134 | { | |
135 | int flushed = 0; | |
136 | struct fib_table *tb; | |
137 | struct hlist_node *node; | |
138 | struct hlist_head *head; | |
139 | unsigned int h; | |
140 | ||
141 | for (h = 0; h < FIB_TABLE_HASHSZ; h++) { | |
142 | head = &net->ipv4.fib_table_hash[h]; | |
143 | hlist_for_each_entry(tb, node, head, tb_hlist) | |
144 | flushed += tb->tb_flush(tb); | |
145 | } | |
146 | ||
147 | if (flushed) | |
148 | rt_cache_flush(-1); | |
149 | } | |
150 | ||
151 | /* | |
152 | * Find the first device with a given source address. | |
153 | */ | |
154 | ||
155 | struct net_device * ip_dev_find(__be32 addr) | |
156 | { | |
157 | struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } }; | |
158 | struct fib_result res; | |
159 | struct net_device *dev = NULL; | |
160 | struct fib_table *local_table; | |
161 | ||
162 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
163 | res.r = NULL; | |
164 | #endif | |
165 | ||
166 | local_table = fib_get_table(&init_net, RT_TABLE_LOCAL); | |
167 | if (!local_table || local_table->tb_lookup(local_table, &fl, &res)) | |
168 | return NULL; | |
169 | if (res.type != RTN_LOCAL) | |
170 | goto out; | |
171 | dev = FIB_RES_DEV(res); | |
172 | ||
173 | if (dev) | |
174 | dev_hold(dev); | |
175 | out: | |
176 | fib_res_put(&res); | |
177 | return dev; | |
178 | } | |
179 | ||
180 | /* | |
181 | * Find address type as if only "dev" was present in the system. If | |
182 | * on_dev is NULL then all interfaces are taken into consideration. | |
183 | */ | |
184 | static inline unsigned __inet_dev_addr_type(struct net *net, | |
185 | const struct net_device *dev, | |
186 | __be32 addr) | |
187 | { | |
188 | struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } }; | |
189 | struct fib_result res; | |
190 | unsigned ret = RTN_BROADCAST; | |
191 | struct fib_table *local_table; | |
192 | ||
193 | if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) | |
194 | return RTN_BROADCAST; | |
195 | if (ipv4_is_multicast(addr)) | |
196 | return RTN_MULTICAST; | |
197 | ||
198 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
199 | res.r = NULL; | |
200 | #endif | |
201 | ||
202 | local_table = fib_get_table(net, RT_TABLE_LOCAL); | |
203 | if (local_table) { | |
204 | ret = RTN_UNICAST; | |
205 | if (!local_table->tb_lookup(local_table, &fl, &res)) { | |
206 | if (!dev || dev == res.fi->fib_dev) | |
207 | ret = res.type; | |
208 | fib_res_put(&res); | |
209 | } | |
210 | } | |
211 | return ret; | |
212 | } | |
213 | ||
214 | unsigned int inet_addr_type(struct net *net, __be32 addr) | |
215 | { | |
216 | return __inet_dev_addr_type(net, NULL, addr); | |
217 | } | |
218 | ||
219 | unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, | |
220 | __be32 addr) | |
221 | { | |
222 | return __inet_dev_addr_type(net, dev, addr); | |
223 | } | |
224 | ||
225 | /* Given (packet source, input interface) and optional (dst, oif, tos): | |
226 | - (main) check, that source is valid i.e. not broadcast or our local | |
227 | address. | |
228 | - figure out what "logical" interface this packet arrived | |
229 | and calculate "specific destination" address. | |
230 | - check, that packet arrived from expected physical interface. | |
231 | */ | |
232 | ||
233 | int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif, | |
234 | struct net_device *dev, __be32 *spec_dst, u32 *itag) | |
235 | { | |
236 | struct in_device *in_dev; | |
237 | struct flowi fl = { .nl_u = { .ip4_u = | |
238 | { .daddr = src, | |
239 | .saddr = dst, | |
240 | .tos = tos } }, | |
241 | .iif = oif }; | |
242 | struct fib_result res; | |
243 | int no_addr, rpf; | |
244 | int ret; | |
245 | struct net *net; | |
246 | ||
247 | no_addr = rpf = 0; | |
248 | rcu_read_lock(); | |
249 | in_dev = __in_dev_get_rcu(dev); | |
250 | if (in_dev) { | |
251 | no_addr = in_dev->ifa_list == NULL; | |
252 | rpf = IN_DEV_RPFILTER(in_dev); | |
253 | } | |
254 | rcu_read_unlock(); | |
255 | ||
256 | if (in_dev == NULL) | |
257 | goto e_inval; | |
258 | ||
259 | net = dev->nd_net; | |
260 | if (fib_lookup(net, &fl, &res)) | |
261 | goto last_resort; | |
262 | if (res.type != RTN_UNICAST) | |
263 | goto e_inval_res; | |
264 | *spec_dst = FIB_RES_PREFSRC(res); | |
265 | fib_combine_itag(itag, &res); | |
266 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
267 | if (FIB_RES_DEV(res) == dev || res.fi->fib_nhs > 1) | |
268 | #else | |
269 | if (FIB_RES_DEV(res) == dev) | |
270 | #endif | |
271 | { | |
272 | ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; | |
273 | fib_res_put(&res); | |
274 | return ret; | |
275 | } | |
276 | fib_res_put(&res); | |
277 | if (no_addr) | |
278 | goto last_resort; | |
279 | if (rpf) | |
280 | goto e_inval; | |
281 | fl.oif = dev->ifindex; | |
282 | ||
283 | ret = 0; | |
284 | if (fib_lookup(net, &fl, &res) == 0) { | |
285 | if (res.type == RTN_UNICAST) { | |
286 | *spec_dst = FIB_RES_PREFSRC(res); | |
287 | ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; | |
288 | } | |
289 | fib_res_put(&res); | |
290 | } | |
291 | return ret; | |
292 | ||
293 | last_resort: | |
294 | if (rpf) | |
295 | goto e_inval; | |
296 | *spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
297 | *itag = 0; | |
298 | return 0; | |
299 | ||
300 | e_inval_res: | |
301 | fib_res_put(&res); | |
302 | e_inval: | |
303 | return -EINVAL; | |
304 | } | |
305 | ||
306 | static inline __be32 sk_extract_addr(struct sockaddr *addr) | |
307 | { | |
308 | return ((struct sockaddr_in *) addr)->sin_addr.s_addr; | |
309 | } | |
310 | ||
311 | static int put_rtax(struct nlattr *mx, int len, int type, u32 value) | |
312 | { | |
313 | struct nlattr *nla; | |
314 | ||
315 | nla = (struct nlattr *) ((char *) mx + len); | |
316 | nla->nla_type = type; | |
317 | nla->nla_len = nla_attr_size(4); | |
318 | *(u32 *) nla_data(nla) = value; | |
319 | ||
320 | return len + nla_total_size(4); | |
321 | } | |
322 | ||
323 | static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, | |
324 | struct fib_config *cfg) | |
325 | { | |
326 | __be32 addr; | |
327 | int plen; | |
328 | ||
329 | memset(cfg, 0, sizeof(*cfg)); | |
330 | cfg->fc_nlinfo.nl_net = net; | |
331 | ||
332 | if (rt->rt_dst.sa_family != AF_INET) | |
333 | return -EAFNOSUPPORT; | |
334 | ||
335 | /* | |
336 | * Check mask for validity: | |
337 | * a) it must be contiguous. | |
338 | * b) destination must have all host bits clear. | |
339 | * c) if application forgot to set correct family (AF_INET), | |
340 | * reject request unless it is absolutely clear i.e. | |
341 | * both family and mask are zero. | |
342 | */ | |
343 | plen = 32; | |
344 | addr = sk_extract_addr(&rt->rt_dst); | |
345 | if (!(rt->rt_flags & RTF_HOST)) { | |
346 | __be32 mask = sk_extract_addr(&rt->rt_genmask); | |
347 | ||
348 | if (rt->rt_genmask.sa_family != AF_INET) { | |
349 | if (mask || rt->rt_genmask.sa_family) | |
350 | return -EAFNOSUPPORT; | |
351 | } | |
352 | ||
353 | if (bad_mask(mask, addr)) | |
354 | return -EINVAL; | |
355 | ||
356 | plen = inet_mask_len(mask); | |
357 | } | |
358 | ||
359 | cfg->fc_dst_len = plen; | |
360 | cfg->fc_dst = addr; | |
361 | ||
362 | if (cmd != SIOCDELRT) { | |
363 | cfg->fc_nlflags = NLM_F_CREATE; | |
364 | cfg->fc_protocol = RTPROT_BOOT; | |
365 | } | |
366 | ||
367 | if (rt->rt_metric) | |
368 | cfg->fc_priority = rt->rt_metric - 1; | |
369 | ||
370 | if (rt->rt_flags & RTF_REJECT) { | |
371 | cfg->fc_scope = RT_SCOPE_HOST; | |
372 | cfg->fc_type = RTN_UNREACHABLE; | |
373 | return 0; | |
374 | } | |
375 | ||
376 | cfg->fc_scope = RT_SCOPE_NOWHERE; | |
377 | cfg->fc_type = RTN_UNICAST; | |
378 | ||
379 | if (rt->rt_dev) { | |
380 | char *colon; | |
381 | struct net_device *dev; | |
382 | char devname[IFNAMSIZ]; | |
383 | ||
384 | if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) | |
385 | return -EFAULT; | |
386 | ||
387 | devname[IFNAMSIZ-1] = 0; | |
388 | colon = strchr(devname, ':'); | |
389 | if (colon) | |
390 | *colon = 0; | |
391 | dev = __dev_get_by_name(net, devname); | |
392 | if (!dev) | |
393 | return -ENODEV; | |
394 | cfg->fc_oif = dev->ifindex; | |
395 | if (colon) { | |
396 | struct in_ifaddr *ifa; | |
397 | struct in_device *in_dev = __in_dev_get_rtnl(dev); | |
398 | if (!in_dev) | |
399 | return -ENODEV; | |
400 | *colon = ':'; | |
401 | for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) | |
402 | if (strcmp(ifa->ifa_label, devname) == 0) | |
403 | break; | |
404 | if (ifa == NULL) | |
405 | return -ENODEV; | |
406 | cfg->fc_prefsrc = ifa->ifa_local; | |
407 | } | |
408 | } | |
409 | ||
410 | addr = sk_extract_addr(&rt->rt_gateway); | |
411 | if (rt->rt_gateway.sa_family == AF_INET && addr) { | |
412 | cfg->fc_gw = addr; | |
413 | if (rt->rt_flags & RTF_GATEWAY && | |
414 | inet_addr_type(net, addr) == RTN_UNICAST) | |
415 | cfg->fc_scope = RT_SCOPE_UNIVERSE; | |
416 | } | |
417 | ||
418 | if (cmd == SIOCDELRT) | |
419 | return 0; | |
420 | ||
421 | if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw) | |
422 | return -EINVAL; | |
423 | ||
424 | if (cfg->fc_scope == RT_SCOPE_NOWHERE) | |
425 | cfg->fc_scope = RT_SCOPE_LINK; | |
426 | ||
427 | if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { | |
428 | struct nlattr *mx; | |
429 | int len = 0; | |
430 | ||
431 | mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL); | |
432 | if (mx == NULL) | |
433 | return -ENOMEM; | |
434 | ||
435 | if (rt->rt_flags & RTF_MTU) | |
436 | len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); | |
437 | ||
438 | if (rt->rt_flags & RTF_WINDOW) | |
439 | len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); | |
440 | ||
441 | if (rt->rt_flags & RTF_IRTT) | |
442 | len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); | |
443 | ||
444 | cfg->fc_mx = mx; | |
445 | cfg->fc_mx_len = len; | |
446 | } | |
447 | ||
448 | return 0; | |
449 | } | |
450 | ||
451 | /* | |
452 | * Handle IP routing ioctl calls. These are used to manipulate the routing tables | |
453 | */ | |
454 | ||
455 | int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg) | |
456 | { | |
457 | struct fib_config cfg; | |
458 | struct rtentry rt; | |
459 | int err; | |
460 | ||
461 | switch (cmd) { | |
462 | case SIOCADDRT: /* Add a route */ | |
463 | case SIOCDELRT: /* Delete a route */ | |
464 | if (!capable(CAP_NET_ADMIN)) | |
465 | return -EPERM; | |
466 | ||
467 | if (copy_from_user(&rt, arg, sizeof(rt))) | |
468 | return -EFAULT; | |
469 | ||
470 | rtnl_lock(); | |
471 | err = rtentry_to_fib_config(net, cmd, &rt, &cfg); | |
472 | if (err == 0) { | |
473 | struct fib_table *tb; | |
474 | ||
475 | if (cmd == SIOCDELRT) { | |
476 | tb = fib_get_table(net, cfg.fc_table); | |
477 | if (tb) | |
478 | err = tb->tb_delete(tb, &cfg); | |
479 | else | |
480 | err = -ESRCH; | |
481 | } else { | |
482 | tb = fib_new_table(net, cfg.fc_table); | |
483 | if (tb) | |
484 | err = tb->tb_insert(tb, &cfg); | |
485 | else | |
486 | err = -ENOBUFS; | |
487 | } | |
488 | ||
489 | /* allocated by rtentry_to_fib_config() */ | |
490 | kfree(cfg.fc_mx); | |
491 | } | |
492 | rtnl_unlock(); | |
493 | return err; | |
494 | } | |
495 | return -EINVAL; | |
496 | } | |
497 | ||
498 | const struct nla_policy rtm_ipv4_policy[RTA_MAX+1] = { | |
499 | [RTA_DST] = { .type = NLA_U32 }, | |
500 | [RTA_SRC] = { .type = NLA_U32 }, | |
501 | [RTA_IIF] = { .type = NLA_U32 }, | |
502 | [RTA_OIF] = { .type = NLA_U32 }, | |
503 | [RTA_GATEWAY] = { .type = NLA_U32 }, | |
504 | [RTA_PRIORITY] = { .type = NLA_U32 }, | |
505 | [RTA_PREFSRC] = { .type = NLA_U32 }, | |
506 | [RTA_METRICS] = { .type = NLA_NESTED }, | |
507 | [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, | |
508 | [RTA_PROTOINFO] = { .type = NLA_U32 }, | |
509 | [RTA_FLOW] = { .type = NLA_U32 }, | |
510 | }; | |
511 | ||
512 | static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, | |
513 | struct nlmsghdr *nlh, struct fib_config *cfg) | |
514 | { | |
515 | struct nlattr *attr; | |
516 | int err, remaining; | |
517 | struct rtmsg *rtm; | |
518 | ||
519 | err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy); | |
520 | if (err < 0) | |
521 | goto errout; | |
522 | ||
523 | memset(cfg, 0, sizeof(*cfg)); | |
524 | ||
525 | rtm = nlmsg_data(nlh); | |
526 | cfg->fc_dst_len = rtm->rtm_dst_len; | |
527 | cfg->fc_tos = rtm->rtm_tos; | |
528 | cfg->fc_table = rtm->rtm_table; | |
529 | cfg->fc_protocol = rtm->rtm_protocol; | |
530 | cfg->fc_scope = rtm->rtm_scope; | |
531 | cfg->fc_type = rtm->rtm_type; | |
532 | cfg->fc_flags = rtm->rtm_flags; | |
533 | cfg->fc_nlflags = nlh->nlmsg_flags; | |
534 | ||
535 | cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid; | |
536 | cfg->fc_nlinfo.nlh = nlh; | |
537 | cfg->fc_nlinfo.nl_net = net; | |
538 | ||
539 | if (cfg->fc_type > RTN_MAX) { | |
540 | err = -EINVAL; | |
541 | goto errout; | |
542 | } | |
543 | ||
544 | nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { | |
545 | switch (nla_type(attr)) { | |
546 | case RTA_DST: | |
547 | cfg->fc_dst = nla_get_be32(attr); | |
548 | break; | |
549 | case RTA_OIF: | |
550 | cfg->fc_oif = nla_get_u32(attr); | |
551 | break; | |
552 | case RTA_GATEWAY: | |
553 | cfg->fc_gw = nla_get_be32(attr); | |
554 | break; | |
555 | case RTA_PRIORITY: | |
556 | cfg->fc_priority = nla_get_u32(attr); | |
557 | break; | |
558 | case RTA_PREFSRC: | |
559 | cfg->fc_prefsrc = nla_get_be32(attr); | |
560 | break; | |
561 | case RTA_METRICS: | |
562 | cfg->fc_mx = nla_data(attr); | |
563 | cfg->fc_mx_len = nla_len(attr); | |
564 | break; | |
565 | case RTA_MULTIPATH: | |
566 | cfg->fc_mp = nla_data(attr); | |
567 | cfg->fc_mp_len = nla_len(attr); | |
568 | break; | |
569 | case RTA_FLOW: | |
570 | cfg->fc_flow = nla_get_u32(attr); | |
571 | break; | |
572 | case RTA_TABLE: | |
573 | cfg->fc_table = nla_get_u32(attr); | |
574 | break; | |
575 | } | |
576 | } | |
577 | ||
578 | return 0; | |
579 | errout: | |
580 | return err; | |
581 | } | |
582 | ||
583 | static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) | |
584 | { | |
585 | struct net *net = skb->sk->sk_net; | |
586 | struct fib_config cfg; | |
587 | struct fib_table *tb; | |
588 | int err; | |
589 | ||
590 | err = rtm_to_fib_config(net, skb, nlh, &cfg); | |
591 | if (err < 0) | |
592 | goto errout; | |
593 | ||
594 | tb = fib_get_table(net, cfg.fc_table); | |
595 | if (tb == NULL) { | |
596 | err = -ESRCH; | |
597 | goto errout; | |
598 | } | |
599 | ||
600 | err = tb->tb_delete(tb, &cfg); | |
601 | errout: | |
602 | return err; | |
603 | } | |
604 | ||
605 | static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) | |
606 | { | |
607 | struct net *net = skb->sk->sk_net; | |
608 | struct fib_config cfg; | |
609 | struct fib_table *tb; | |
610 | int err; | |
611 | ||
612 | err = rtm_to_fib_config(net, skb, nlh, &cfg); | |
613 | if (err < 0) | |
614 | goto errout; | |
615 | ||
616 | tb = fib_new_table(net, cfg.fc_table); | |
617 | if (tb == NULL) { | |
618 | err = -ENOBUFS; | |
619 | goto errout; | |
620 | } | |
621 | ||
622 | err = tb->tb_insert(tb, &cfg); | |
623 | errout: | |
624 | return err; | |
625 | } | |
626 | ||
627 | static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) | |
628 | { | |
629 | struct net *net = skb->sk->sk_net; | |
630 | unsigned int h, s_h; | |
631 | unsigned int e = 0, s_e; | |
632 | struct fib_table *tb; | |
633 | struct hlist_node *node; | |
634 | struct hlist_head *head; | |
635 | int dumped = 0; | |
636 | ||
637 | if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) && | |
638 | ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED) | |
639 | return ip_rt_dump(skb, cb); | |
640 | ||
641 | s_h = cb->args[0]; | |
642 | s_e = cb->args[1]; | |
643 | ||
644 | for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { | |
645 | e = 0; | |
646 | head = &net->ipv4.fib_table_hash[h]; | |
647 | hlist_for_each_entry(tb, node, head, tb_hlist) { | |
648 | if (e < s_e) | |
649 | goto next; | |
650 | if (dumped) | |
651 | memset(&cb->args[2], 0, sizeof(cb->args) - | |
652 | 2 * sizeof(cb->args[0])); | |
653 | if (tb->tb_dump(tb, skb, cb) < 0) | |
654 | goto out; | |
655 | dumped = 1; | |
656 | next: | |
657 | e++; | |
658 | } | |
659 | } | |
660 | out: | |
661 | cb->args[1] = e; | |
662 | cb->args[0] = h; | |
663 | ||
664 | return skb->len; | |
665 | } | |
666 | ||
667 | /* Prepare and feed intra-kernel routing request. | |
668 | Really, it should be netlink message, but :-( netlink | |
669 | can be not configured, so that we feed it directly | |
670 | to fib engine. It is legal, because all events occur | |
671 | only when netlink is already locked. | |
672 | */ | |
673 | ||
674 | static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa) | |
675 | { | |
676 | struct net *net = ifa->ifa_dev->dev->nd_net; | |
677 | struct fib_table *tb; | |
678 | struct fib_config cfg = { | |
679 | .fc_protocol = RTPROT_KERNEL, | |
680 | .fc_type = type, | |
681 | .fc_dst = dst, | |
682 | .fc_dst_len = dst_len, | |
683 | .fc_prefsrc = ifa->ifa_local, | |
684 | .fc_oif = ifa->ifa_dev->dev->ifindex, | |
685 | .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, | |
686 | .fc_nlinfo = { | |
687 | .nl_net = net, | |
688 | }, | |
689 | }; | |
690 | ||
691 | if (type == RTN_UNICAST) | |
692 | tb = fib_new_table(net, RT_TABLE_MAIN); | |
693 | else | |
694 | tb = fib_new_table(net, RT_TABLE_LOCAL); | |
695 | ||
696 | if (tb == NULL) | |
697 | return; | |
698 | ||
699 | cfg.fc_table = tb->tb_id; | |
700 | ||
701 | if (type != RTN_LOCAL) | |
702 | cfg.fc_scope = RT_SCOPE_LINK; | |
703 | else | |
704 | cfg.fc_scope = RT_SCOPE_HOST; | |
705 | ||
706 | if (cmd == RTM_NEWROUTE) | |
707 | tb->tb_insert(tb, &cfg); | |
708 | else | |
709 | tb->tb_delete(tb, &cfg); | |
710 | } | |
711 | ||
712 | void fib_add_ifaddr(struct in_ifaddr *ifa) | |
713 | { | |
714 | struct in_device *in_dev = ifa->ifa_dev; | |
715 | struct net_device *dev = in_dev->dev; | |
716 | struct in_ifaddr *prim = ifa; | |
717 | __be32 mask = ifa->ifa_mask; | |
718 | __be32 addr = ifa->ifa_local; | |
719 | __be32 prefix = ifa->ifa_address&mask; | |
720 | ||
721 | if (ifa->ifa_flags&IFA_F_SECONDARY) { | |
722 | prim = inet_ifa_byprefix(in_dev, prefix, mask); | |
723 | if (prim == NULL) { | |
724 | printk(KERN_WARNING "fib_add_ifaddr: bug: prim == NULL\n"); | |
725 | return; | |
726 | } | |
727 | } | |
728 | ||
729 | fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim); | |
730 | ||
731 | if (!(dev->flags&IFF_UP)) | |
732 | return; | |
733 | ||
734 | /* Add broadcast address, if it is explicitly assigned. */ | |
735 | if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) | |
736 | fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); | |
737 | ||
738 | if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags&IFA_F_SECONDARY) && | |
739 | (prefix != addr || ifa->ifa_prefixlen < 32)) { | |
740 | fib_magic(RTM_NEWROUTE, dev->flags&IFF_LOOPBACK ? RTN_LOCAL : | |
741 | RTN_UNICAST, prefix, ifa->ifa_prefixlen, prim); | |
742 | ||
743 | /* Add network specific broadcasts, when it takes a sense */ | |
744 | if (ifa->ifa_prefixlen < 31) { | |
745 | fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim); | |
746 | fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix|~mask, 32, prim); | |
747 | } | |
748 | } | |
749 | } | |
750 | ||
751 | static void fib_del_ifaddr(struct in_ifaddr *ifa) | |
752 | { | |
753 | struct in_device *in_dev = ifa->ifa_dev; | |
754 | struct net_device *dev = in_dev->dev; | |
755 | struct in_ifaddr *ifa1; | |
756 | struct in_ifaddr *prim = ifa; | |
757 | __be32 brd = ifa->ifa_address|~ifa->ifa_mask; | |
758 | __be32 any = ifa->ifa_address&ifa->ifa_mask; | |
759 | #define LOCAL_OK 1 | |
760 | #define BRD_OK 2 | |
761 | #define BRD0_OK 4 | |
762 | #define BRD1_OK 8 | |
763 | unsigned ok = 0; | |
764 | ||
765 | if (!(ifa->ifa_flags&IFA_F_SECONDARY)) | |
766 | fib_magic(RTM_DELROUTE, dev->flags&IFF_LOOPBACK ? RTN_LOCAL : | |
767 | RTN_UNICAST, any, ifa->ifa_prefixlen, prim); | |
768 | else { | |
769 | prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); | |
770 | if (prim == NULL) { | |
771 | printk(KERN_WARNING "fib_del_ifaddr: bug: prim == NULL\n"); | |
772 | return; | |
773 | } | |
774 | } | |
775 | ||
776 | /* Deletion is more complicated than add. | |
777 | We should take care of not to delete too much :-) | |
778 | ||
779 | Scan address list to be sure that addresses are really gone. | |
780 | */ | |
781 | ||
782 | for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) { | |
783 | if (ifa->ifa_local == ifa1->ifa_local) | |
784 | ok |= LOCAL_OK; | |
785 | if (ifa->ifa_broadcast == ifa1->ifa_broadcast) | |
786 | ok |= BRD_OK; | |
787 | if (brd == ifa1->ifa_broadcast) | |
788 | ok |= BRD1_OK; | |
789 | if (any == ifa1->ifa_broadcast) | |
790 | ok |= BRD0_OK; | |
791 | } | |
792 | ||
793 | if (!(ok&BRD_OK)) | |
794 | fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); | |
795 | if (!(ok&BRD1_OK)) | |
796 | fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim); | |
797 | if (!(ok&BRD0_OK)) | |
798 | fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim); | |
799 | if (!(ok&LOCAL_OK)) { | |
800 | fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim); | |
801 | ||
802 | /* Check, that this local address finally disappeared. */ | |
803 | if (inet_addr_type(dev->nd_net, ifa->ifa_local) != RTN_LOCAL) { | |
804 | /* And the last, but not the least thing. | |
805 | We must flush stray FIB entries. | |
806 | ||
807 | First of all, we scan fib_info list searching | |
808 | for stray nexthop entries, then ignite fib_flush. | |
809 | */ | |
810 | if (fib_sync_down(ifa->ifa_local, NULL, 0)) | |
811 | fib_flush(dev->nd_net); | |
812 | } | |
813 | } | |
814 | #undef LOCAL_OK | |
815 | #undef BRD_OK | |
816 | #undef BRD0_OK | |
817 | #undef BRD1_OK | |
818 | } | |
819 | ||
820 | static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb ) | |
821 | { | |
822 | ||
823 | struct fib_result res; | |
824 | struct flowi fl = { .mark = frn->fl_mark, | |
825 | .nl_u = { .ip4_u = { .daddr = frn->fl_addr, | |
826 | .tos = frn->fl_tos, | |
827 | .scope = frn->fl_scope } } }; | |
828 | ||
829 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
830 | res.r = NULL; | |
831 | #endif | |
832 | ||
833 | frn->err = -ENOENT; | |
834 | if (tb) { | |
835 | local_bh_disable(); | |
836 | ||
837 | frn->tb_id = tb->tb_id; | |
838 | frn->err = tb->tb_lookup(tb, &fl, &res); | |
839 | ||
840 | if (!frn->err) { | |
841 | frn->prefixlen = res.prefixlen; | |
842 | frn->nh_sel = res.nh_sel; | |
843 | frn->type = res.type; | |
844 | frn->scope = res.scope; | |
845 | fib_res_put(&res); | |
846 | } | |
847 | local_bh_enable(); | |
848 | } | |
849 | } | |
850 | ||
851 | static void nl_fib_input(struct sk_buff *skb) | |
852 | { | |
853 | struct net *net; | |
854 | struct fib_result_nl *frn; | |
855 | struct nlmsghdr *nlh; | |
856 | struct fib_table *tb; | |
857 | u32 pid; | |
858 | ||
859 | net = skb->sk->sk_net; | |
860 | nlh = nlmsg_hdr(skb); | |
861 | if (skb->len < NLMSG_SPACE(0) || skb->len < nlh->nlmsg_len || | |
862 | nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*frn))) | |
863 | return; | |
864 | ||
865 | skb = skb_clone(skb, GFP_KERNEL); | |
866 | if (skb == NULL) | |
867 | return; | |
868 | nlh = nlmsg_hdr(skb); | |
869 | ||
870 | frn = (struct fib_result_nl *) NLMSG_DATA(nlh); | |
871 | tb = fib_get_table(net, frn->tb_id_in); | |
872 | ||
873 | nl_fib_lookup(frn, tb); | |
874 | ||
875 | pid = NETLINK_CB(skb).pid; /* pid of sending process */ | |
876 | NETLINK_CB(skb).pid = 0; /* from kernel */ | |
877 | NETLINK_CB(skb).dst_group = 0; /* unicast */ | |
878 | netlink_unicast(net->ipv4.fibnl, skb, pid, MSG_DONTWAIT); | |
879 | } | |
880 | ||
881 | static int nl_fib_lookup_init(struct net *net) | |
882 | { | |
883 | struct sock *sk; | |
884 | sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, 0, | |
885 | nl_fib_input, NULL, THIS_MODULE); | |
886 | if (sk == NULL) | |
887 | return -EAFNOSUPPORT; | |
888 | net->ipv4.fibnl = sk; | |
889 | return 0; | |
890 | } | |
891 | ||
892 | static void nl_fib_lookup_exit(struct net *net) | |
893 | { | |
894 | netlink_kernel_release(net->ipv4.fibnl); | |
895 | net->ipv4.fibnl = NULL; | |
896 | } | |
897 | ||
898 | static void fib_disable_ip(struct net_device *dev, int force) | |
899 | { | |
900 | if (fib_sync_down(0, dev, force)) | |
901 | fib_flush(dev->nd_net); | |
902 | rt_cache_flush(0); | |
903 | arp_ifdown(dev); | |
904 | } | |
905 | ||
906 | static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) | |
907 | { | |
908 | struct in_ifaddr *ifa = (struct in_ifaddr*)ptr; | |
909 | ||
910 | switch (event) { | |
911 | case NETDEV_UP: | |
912 | fib_add_ifaddr(ifa); | |
913 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
914 | fib_sync_up(ifa->ifa_dev->dev); | |
915 | #endif | |
916 | rt_cache_flush(-1); | |
917 | break; | |
918 | case NETDEV_DOWN: | |
919 | fib_del_ifaddr(ifa); | |
920 | if (ifa->ifa_dev->ifa_list == NULL) { | |
921 | /* Last address was deleted from this interface. | |
922 | Disable IP. | |
923 | */ | |
924 | fib_disable_ip(ifa->ifa_dev->dev, 1); | |
925 | } else { | |
926 | rt_cache_flush(-1); | |
927 | } | |
928 | break; | |
929 | } | |
930 | return NOTIFY_DONE; | |
931 | } | |
932 | ||
933 | static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) | |
934 | { | |
935 | struct net_device *dev = ptr; | |
936 | struct in_device *in_dev = __in_dev_get_rtnl(dev); | |
937 | ||
938 | if (event == NETDEV_UNREGISTER) { | |
939 | fib_disable_ip(dev, 2); | |
940 | return NOTIFY_DONE; | |
941 | } | |
942 | ||
943 | if (!in_dev) | |
944 | return NOTIFY_DONE; | |
945 | ||
946 | switch (event) { | |
947 | case NETDEV_UP: | |
948 | for_ifa(in_dev) { | |
949 | fib_add_ifaddr(ifa); | |
950 | } endfor_ifa(in_dev); | |
951 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
952 | fib_sync_up(dev); | |
953 | #endif | |
954 | rt_cache_flush(-1); | |
955 | break; | |
956 | case NETDEV_DOWN: | |
957 | fib_disable_ip(dev, 0); | |
958 | break; | |
959 | case NETDEV_CHANGEMTU: | |
960 | case NETDEV_CHANGE: | |
961 | rt_cache_flush(0); | |
962 | break; | |
963 | } | |
964 | return NOTIFY_DONE; | |
965 | } | |
966 | ||
967 | static struct notifier_block fib_inetaddr_notifier = { | |
968 | .notifier_call =fib_inetaddr_event, | |
969 | }; | |
970 | ||
971 | static struct notifier_block fib_netdev_notifier = { | |
972 | .notifier_call =fib_netdev_event, | |
973 | }; | |
974 | ||
975 | static int __net_init ip_fib_net_init(struct net *net) | |
976 | { | |
977 | unsigned int i; | |
978 | ||
979 | net->ipv4.fib_table_hash = kzalloc( | |
980 | sizeof(struct hlist_head)*FIB_TABLE_HASHSZ, GFP_KERNEL); | |
981 | if (net->ipv4.fib_table_hash == NULL) | |
982 | return -ENOMEM; | |
983 | ||
984 | for (i = 0; i < FIB_TABLE_HASHSZ; i++) | |
985 | INIT_HLIST_HEAD(&net->ipv4.fib_table_hash[i]); | |
986 | ||
987 | return fib4_rules_init(net); | |
988 | } | |
989 | ||
990 | static void __net_exit ip_fib_net_exit(struct net *net) | |
991 | { | |
992 | unsigned int i; | |
993 | ||
994 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
995 | fib4_rules_exit(net); | |
996 | #endif | |
997 | ||
998 | for (i = 0; i < FIB_TABLE_HASHSZ; i++) { | |
999 | struct fib_table *tb; | |
1000 | struct hlist_head *head; | |
1001 | struct hlist_node *node, *tmp; | |
1002 | ||
1003 | head = &net->ipv4.fib_table_hash[i]; | |
1004 | hlist_for_each_entry_safe(tb, node, tmp, head, tb_hlist) { | |
1005 | hlist_del(node); | |
1006 | tb->tb_flush(tb); | |
1007 | kfree(tb); | |
1008 | } | |
1009 | } | |
1010 | kfree(net->ipv4.fib_table_hash); | |
1011 | } | |
1012 | ||
1013 | static int __net_init fib_net_init(struct net *net) | |
1014 | { | |
1015 | int error; | |
1016 | ||
1017 | error = ip_fib_net_init(net); | |
1018 | if (error < 0) | |
1019 | goto out; | |
1020 | error = nl_fib_lookup_init(net); | |
1021 | if (error < 0) | |
1022 | goto out_nlfl; | |
1023 | error = fib_proc_init(net); | |
1024 | if (error < 0) | |
1025 | goto out_proc; | |
1026 | out: | |
1027 | return error; | |
1028 | ||
1029 | out_proc: | |
1030 | nl_fib_lookup_exit(net); | |
1031 | out_nlfl: | |
1032 | ip_fib_net_exit(net); | |
1033 | goto out; | |
1034 | } | |
1035 | ||
1036 | static void __net_exit fib_net_exit(struct net *net) | |
1037 | { | |
1038 | fib_proc_exit(net); | |
1039 | nl_fib_lookup_exit(net); | |
1040 | ip_fib_net_exit(net); | |
1041 | } | |
1042 | ||
1043 | static struct pernet_operations fib_net_ops = { | |
1044 | .init = fib_net_init, | |
1045 | .exit = fib_net_exit, | |
1046 | }; | |
1047 | ||
1048 | void __init ip_fib_init(void) | |
1049 | { | |
1050 | rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL); | |
1051 | rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL); | |
1052 | rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib); | |
1053 | ||
1054 | register_pernet_subsys(&fib_net_ops); | |
1055 | register_netdevice_notifier(&fib_netdev_notifier); | |
1056 | register_inetaddr_notifier(&fib_inetaddr_notifier); | |
1057 | ||
1058 | fib_hash_init(); | |
1059 | } | |
1060 | ||
1061 | EXPORT_SYMBOL(inet_addr_type); | |
1062 | EXPORT_SYMBOL(inet_dev_addr_type); | |
1063 | EXPORT_SYMBOL(ip_dev_find); |