projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
[NETNS]: Provide correct namespace for fibnl netlink socket.
[deliverable/linux.git] / net / ipv4 / fib_frontend.c
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 #define FFprint(a...) printk(KERN_DEBUG a)
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 local_table = fib_hash_init(RT_TABLE_LOCAL);
59 if (local_table == NULL)
60 return -ENOMEM;
61
62 main_table = fib_hash_init(RT_TABLE_MAIN);
63 if (main_table == NULL)
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 kfree(local_table);
74 return -ENOMEM;
75 }
76 #else
77
78 struct fib_table *fib_new_table(struct net *net, u32 id)
79 {
80 struct fib_table *tb;
81 unsigned int h;
82
83 if (id == 0)
84 id = RT_TABLE_MAIN;
85 tb = fib_get_table(net, id);
86 if (tb)
87 return tb;
88 tb = fib_hash_init(id);
89 if (!tb)
90 return NULL;
91 h = id & (FIB_TABLE_HASHSZ - 1);
92 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
93 return tb;
94 }
95
96 struct fib_table *fib_get_table(struct net *net, u32 id)
97 {
98 struct fib_table *tb;
99 struct hlist_node *node;
100 struct hlist_head *head;
101 unsigned int h;
102
103 if (id == 0)
104 id = RT_TABLE_MAIN;
105 h = id & (FIB_TABLE_HASHSZ - 1);
106
107 rcu_read_lock();
108 head = &net->ipv4.fib_table_hash[h];
109 hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
110 if (tb->tb_id == id) {
111 rcu_read_unlock();
112 return tb;
113 }
114 }
115 rcu_read_unlock();
116 return NULL;
117 }
118 #endif /* CONFIG_IP_MULTIPLE_TABLES */
119
120 static void fib_flush(struct net *net)
121 {
122 int flushed = 0;
123 struct fib_table *tb;
124 struct hlist_node *node;
125 struct hlist_head *head;
126 unsigned int h;
127
128 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
129 head = &net->ipv4.fib_table_hash[h];
130 hlist_for_each_entry(tb, node, head, tb_hlist)
131 flushed += tb->tb_flush(tb);
132 }
133
134 if (flushed)
135 rt_cache_flush(-1);
136 }
137
138 /*
139 * Find the first device with a given source address.
140 */
141
142 struct net_device * ip_dev_find(__be32 addr)
143 {
144 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } };
145 struct fib_result res;
146 struct net_device *dev = NULL;
147 struct fib_table *local_table;
148
149 #ifdef CONFIG_IP_MULTIPLE_TABLES
150 res.r = NULL;
151 #endif
152
153 local_table = fib_get_table(&init_net, RT_TABLE_LOCAL);
154 if (!local_table || local_table->tb_lookup(local_table, &fl, &res))
155 return NULL;
156 if (res.type != RTN_LOCAL)
157 goto out;
158 dev = FIB_RES_DEV(res);
159
160 if (dev)
161 dev_hold(dev);
162 out:
163 fib_res_put(&res);
164 return dev;
165 }
166
167 /*
168 * Find address type as if only "dev" was present in the system. If
169 * on_dev is NULL then all interfaces are taken into consideration.
170 */
171 static inline unsigned __inet_dev_addr_type(struct net *net,
172 const struct net_device *dev,
173 __be32 addr)
174 {
175 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } };
176 struct fib_result res;
177 unsigned ret = RTN_BROADCAST;
178 struct fib_table *local_table;
179
180 if (ipv4_is_zeronet(addr) || ipv4_is_badclass(addr))
181 return RTN_BROADCAST;
182 if (ipv4_is_multicast(addr))
183 return RTN_MULTICAST;
184
185 #ifdef CONFIG_IP_MULTIPLE_TABLES
186 res.r = NULL;
187 #endif
188
189 local_table = fib_get_table(net, RT_TABLE_LOCAL);
190 if (local_table) {
191 ret = RTN_UNICAST;
192 if (!local_table->tb_lookup(local_table, &fl, &res)) {
193 if (!dev || dev == res.fi->fib_dev)
194 ret = res.type;
195 fib_res_put(&res);
196 }
197 }
198 return ret;
199 }
200
201 unsigned int inet_addr_type(struct net *net, __be32 addr)
202 {
203 return __inet_dev_addr_type(net, NULL, addr);
204 }
205
206 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
207 __be32 addr)
208 {
209 return __inet_dev_addr_type(net, dev, addr);
210 }
211
212 /* Given (packet source, input interface) and optional (dst, oif, tos):
213 - (main) check, that source is valid i.e. not broadcast or our local
214 address.
215 - figure out what "logical" interface this packet arrived
216 and calculate "specific destination" address.
217 - check, that packet arrived from expected physical interface.
218 */
219
220 int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
221 struct net_device *dev, __be32 *spec_dst, u32 *itag)
222 {
223 struct in_device *in_dev;
224 struct flowi fl = { .nl_u = { .ip4_u =
225 { .daddr = src,
226 .saddr = dst,
227 .tos = tos } },
228 .iif = oif };
229 struct fib_result res;
230 int no_addr, rpf;
231 int ret;
232
233 no_addr = rpf = 0;
234 rcu_read_lock();
235 in_dev = __in_dev_get_rcu(dev);
236 if (in_dev) {
237 no_addr = in_dev->ifa_list == NULL;
238 rpf = IN_DEV_RPFILTER(in_dev);
239 }
240 rcu_read_unlock();
241
242 if (in_dev == NULL)
243 goto e_inval;
244
245 if (fib_lookup(&fl, &res))
246 goto last_resort;
247 if (res.type != RTN_UNICAST)
248 goto e_inval_res;
249 *spec_dst = FIB_RES_PREFSRC(res);
250 fib_combine_itag(itag, &res);
251 #ifdef CONFIG_IP_ROUTE_MULTIPATH
252 if (FIB_RES_DEV(res) == dev || res.fi->fib_nhs > 1)
253 #else
254 if (FIB_RES_DEV(res) == dev)
255 #endif
256 {
257 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
258 fib_res_put(&res);
259 return ret;
260 }
261 fib_res_put(&res);
262 if (no_addr)
263 goto last_resort;
264 if (rpf)
265 goto e_inval;
266 fl.oif = dev->ifindex;
267
268 ret = 0;
269 if (fib_lookup(&fl, &res) == 0) {
270 if (res.type == RTN_UNICAST) {
271 *spec_dst = FIB_RES_PREFSRC(res);
272 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
273 }
274 fib_res_put(&res);
275 }
276 return ret;
277
278 last_resort:
279 if (rpf)
280 goto e_inval;
281 *spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
282 *itag = 0;
283 return 0;
284
285 e_inval_res:
286 fib_res_put(&res);
287 e_inval:
288 return -EINVAL;
289 }
290
291 static inline __be32 sk_extract_addr(struct sockaddr *addr)
292 {
293 return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
294 }
295
296 static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
297 {
298 struct nlattr *nla;
299
300 nla = (struct nlattr *) ((char *) mx + len);
301 nla->nla_type = type;
302 nla->nla_len = nla_attr_size(4);
303 *(u32 *) nla_data(nla) = value;
304
305 return len + nla_total_size(4);
306 }
307
308 static int rtentry_to_fib_config(int cmd, struct rtentry *rt,
309 struct fib_config *cfg)
310 {
311 __be32 addr;
312 int plen;
313
314 memset(cfg, 0, sizeof(*cfg));
315 cfg->fc_nlinfo.nl_net = &init_net;
316
317 if (rt->rt_dst.sa_family != AF_INET)
318 return -EAFNOSUPPORT;
319
320 /*
321 * Check mask for validity:
322 * a) it must be contiguous.
323 * b) destination must have all host bits clear.
324 * c) if application forgot to set correct family (AF_INET),
325 * reject request unless it is absolutely clear i.e.
326 * both family and mask are zero.
327 */
328 plen = 32;
329 addr = sk_extract_addr(&rt->rt_dst);
330 if (!(rt->rt_flags & RTF_HOST)) {
331 __be32 mask = sk_extract_addr(&rt->rt_genmask);
332
333 if (rt->rt_genmask.sa_family != AF_INET) {
334 if (mask || rt->rt_genmask.sa_family)
335 return -EAFNOSUPPORT;
336 }
337
338 if (bad_mask(mask, addr))
339 return -EINVAL;
340
341 plen = inet_mask_len(mask);
342 }
343
344 cfg->fc_dst_len = plen;
345 cfg->fc_dst = addr;
346
347 if (cmd != SIOCDELRT) {
348 cfg->fc_nlflags = NLM_F_CREATE;
349 cfg->fc_protocol = RTPROT_BOOT;
350 }
351
352 if (rt->rt_metric)
353 cfg->fc_priority = rt->rt_metric - 1;
354
355 if (rt->rt_flags & RTF_REJECT) {
356 cfg->fc_scope = RT_SCOPE_HOST;
357 cfg->fc_type = RTN_UNREACHABLE;
358 return 0;
359 }
360
361 cfg->fc_scope = RT_SCOPE_NOWHERE;
362 cfg->fc_type = RTN_UNICAST;
363
364 if (rt->rt_dev) {
365 char *colon;
366 struct net_device *dev;
367 char devname[IFNAMSIZ];
368
369 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
370 return -EFAULT;
371
372 devname[IFNAMSIZ-1] = 0;
373 colon = strchr(devname, ':');
374 if (colon)
375 *colon = 0;
376 dev = __dev_get_by_name(&init_net, devname);
377 if (!dev)
378 return -ENODEV;
379 cfg->fc_oif = dev->ifindex;
380 if (colon) {
381 struct in_ifaddr *ifa;
382 struct in_device *in_dev = __in_dev_get_rtnl(dev);
383 if (!in_dev)
384 return -ENODEV;
385 *colon = ':';
386 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
387 if (strcmp(ifa->ifa_label, devname) == 0)
388 break;
389 if (ifa == NULL)
390 return -ENODEV;
391 cfg->fc_prefsrc = ifa->ifa_local;
392 }
393 }
394
395 addr = sk_extract_addr(&rt->rt_gateway);
396 if (rt->rt_gateway.sa_family == AF_INET && addr) {
397 cfg->fc_gw = addr;
398 if (rt->rt_flags & RTF_GATEWAY &&
399 inet_addr_type(&init_net, addr) == RTN_UNICAST)
400 cfg->fc_scope = RT_SCOPE_UNIVERSE;
401 }
402
403 if (cmd == SIOCDELRT)
404 return 0;
405
406 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
407 return -EINVAL;
408
409 if (cfg->fc_scope == RT_SCOPE_NOWHERE)
410 cfg->fc_scope = RT_SCOPE_LINK;
411
412 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
413 struct nlattr *mx;
414 int len = 0;
415
416 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
417 if (mx == NULL)
418 return -ENOMEM;
419
420 if (rt->rt_flags & RTF_MTU)
421 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
422
423 if (rt->rt_flags & RTF_WINDOW)
424 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
425
426 if (rt->rt_flags & RTF_IRTT)
427 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
428
429 cfg->fc_mx = mx;
430 cfg->fc_mx_len = len;
431 }
432
433 return 0;
434 }
435
436 /*
437 * Handle IP routing ioctl calls. These are used to manipulate the routing tables
438 */
439
440 int ip_rt_ioctl(unsigned int cmd, void __user *arg)
441 {
442 struct fib_config cfg;
443 struct rtentry rt;
444 int err;
445
446 switch (cmd) {
447 case SIOCADDRT: /* Add a route */
448 case SIOCDELRT: /* Delete a route */
449 if (!capable(CAP_NET_ADMIN))
450 return -EPERM;
451
452 if (copy_from_user(&rt, arg, sizeof(rt)))
453 return -EFAULT;
454
455 rtnl_lock();
456 err = rtentry_to_fib_config(cmd, &rt, &cfg);
457 if (err == 0) {
458 struct fib_table *tb;
459
460 if (cmd == SIOCDELRT) {
461 tb = fib_get_table(&init_net, cfg.fc_table);
462 if (tb)
463 err = tb->tb_delete(tb, &cfg);
464 else
465 err = -ESRCH;
466 } else {
467 tb = fib_new_table(&init_net, cfg.fc_table);
468 if (tb)
469 err = tb->tb_insert(tb, &cfg);
470 else
471 err = -ENOBUFS;
472 }
473
474 /* allocated by rtentry_to_fib_config() */
475 kfree(cfg.fc_mx);
476 }
477 rtnl_unlock();
478 return err;
479 }
480 return -EINVAL;
481 }
482
483 const struct nla_policy rtm_ipv4_policy[RTA_MAX+1] = {
484 [RTA_DST] = { .type = NLA_U32 },
485 [RTA_SRC] = { .type = NLA_U32 },
486 [RTA_IIF] = { .type = NLA_U32 },
487 [RTA_OIF] = { .type = NLA_U32 },
488 [RTA_GATEWAY] = { .type = NLA_U32 },
489 [RTA_PRIORITY] = { .type = NLA_U32 },
490 [RTA_PREFSRC] = { .type = NLA_U32 },
491 [RTA_METRICS] = { .type = NLA_NESTED },
492 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
493 [RTA_PROTOINFO] = { .type = NLA_U32 },
494 [RTA_FLOW] = { .type = NLA_U32 },
495 };
496
497 static int rtm_to_fib_config(struct sk_buff *skb, struct nlmsghdr *nlh,
498 struct fib_config *cfg)
499 {
500 struct nlattr *attr;
501 int err, remaining;
502 struct rtmsg *rtm;
503
504 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
505 if (err < 0)
506 goto errout;
507
508 memset(cfg, 0, sizeof(*cfg));
509
510 rtm = nlmsg_data(nlh);
511 cfg->fc_dst_len = rtm->rtm_dst_len;
512 cfg->fc_tos = rtm->rtm_tos;
513 cfg->fc_table = rtm->rtm_table;
514 cfg->fc_protocol = rtm->rtm_protocol;
515 cfg->fc_scope = rtm->rtm_scope;
516 cfg->fc_type = rtm->rtm_type;
517 cfg->fc_flags = rtm->rtm_flags;
518 cfg->fc_nlflags = nlh->nlmsg_flags;
519
520 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
521 cfg->fc_nlinfo.nlh = nlh;
522 cfg->fc_nlinfo.nl_net = &init_net;
523
524 if (cfg->fc_type > RTN_MAX) {
525 err = -EINVAL;
526 goto errout;
527 }
528
529 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
530 switch (nla_type(attr)) {
531 case RTA_DST:
532 cfg->fc_dst = nla_get_be32(attr);
533 break;
534 case RTA_OIF:
535 cfg->fc_oif = nla_get_u32(attr);
536 break;
537 case RTA_GATEWAY:
538 cfg->fc_gw = nla_get_be32(attr);
539 break;
540 case RTA_PRIORITY:
541 cfg->fc_priority = nla_get_u32(attr);
542 break;
543 case RTA_PREFSRC:
544 cfg->fc_prefsrc = nla_get_be32(attr);
545 break;
546 case RTA_METRICS:
547 cfg->fc_mx = nla_data(attr);
548 cfg->fc_mx_len = nla_len(attr);
549 break;
550 case RTA_MULTIPATH:
551 cfg->fc_mp = nla_data(attr);
552 cfg->fc_mp_len = nla_len(attr);
553 break;
554 case RTA_FLOW:
555 cfg->fc_flow = nla_get_u32(attr);
556 break;
557 case RTA_TABLE:
558 cfg->fc_table = nla_get_u32(attr);
559 break;
560 }
561 }
562
563 return 0;
564 errout:
565 return err;
566 }
567
568 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
569 {
570 struct net *net = skb->sk->sk_net;
571 struct fib_config cfg;
572 struct fib_table *tb;
573 int err;
574
575 if (net != &init_net)
576 return -EINVAL;
577
578 err = rtm_to_fib_config(skb, nlh, &cfg);
579 if (err < 0)
580 goto errout;
581
582 tb = fib_get_table(net, cfg.fc_table);
583 if (tb == NULL) {
584 err = -ESRCH;
585 goto errout;
586 }
587
588 err = tb->tb_delete(tb, &cfg);
589 errout:
590 return err;
591 }
592
593 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
594 {
595 struct net *net = skb->sk->sk_net;
596 struct fib_config cfg;
597 struct fib_table *tb;
598 int err;
599
600 if (net != &init_net)
601 return -EINVAL;
602
603 err = rtm_to_fib_config(skb, nlh, &cfg);
604 if (err < 0)
605 goto errout;
606
607 tb = fib_new_table(&init_net, cfg.fc_table);
608 if (tb == NULL) {
609 err = -ENOBUFS;
610 goto errout;
611 }
612
613 err = tb->tb_insert(tb, &cfg);
614 errout:
615 return err;
616 }
617
618 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
619 {
620 struct net *net = skb->sk->sk_net;
621 unsigned int h, s_h;
622 unsigned int e = 0, s_e;
623 struct fib_table *tb;
624 struct hlist_node *node;
625 struct hlist_head *head;
626 int dumped = 0;
627
628 if (net != &init_net)
629 return 0;
630
631 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
632 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
633 return ip_rt_dump(skb, cb);
634
635 s_h = cb->args[0];
636 s_e = cb->args[1];
637
638 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
639 e = 0;
640 head = &net->ipv4.fib_table_hash[h];
641 hlist_for_each_entry(tb, node, head, tb_hlist) {
642 if (e < s_e)
643 goto next;
644 if (dumped)
645 memset(&cb->args[2], 0, sizeof(cb->args) -
646 2 * sizeof(cb->args[0]));
647 if (tb->tb_dump(tb, skb, cb) < 0)
648 goto out;
649 dumped = 1;
650 next:
651 e++;
652 }
653 }
654 out:
655 cb->args[1] = e;
656 cb->args[0] = h;
657
658 return skb->len;
659 }
660
661 /* Prepare and feed intra-kernel routing request.
662 Really, it should be netlink message, but :-( netlink
663 can be not configured, so that we feed it directly
664 to fib engine. It is legal, because all events occur
665 only when netlink is already locked.
666 */
667
668 static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
669 {
670 struct fib_table *tb;
671 struct fib_config cfg = {
672 .fc_protocol = RTPROT_KERNEL,
673 .fc_type = type,
674 .fc_dst = dst,
675 .fc_dst_len = dst_len,
676 .fc_prefsrc = ifa->ifa_local,
677 .fc_oif = ifa->ifa_dev->dev->ifindex,
678 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
679 .fc_nlinfo = {
680 .nl_net = &init_net,
681 },
682 };
683
684 if (type == RTN_UNICAST)
685 tb = fib_new_table(&init_net, RT_TABLE_MAIN);
686 else
687 tb = fib_new_table(&init_net, RT_TABLE_LOCAL);
688
689 if (tb == NULL)
690 return;
691
692 cfg.fc_table = tb->tb_id;
693
694 if (type != RTN_LOCAL)
695 cfg.fc_scope = RT_SCOPE_LINK;
696 else
697 cfg.fc_scope = RT_SCOPE_HOST;
698
699 if (cmd == RTM_NEWROUTE)
700 tb->tb_insert(tb, &cfg);
701 else
702 tb->tb_delete(tb, &cfg);
703 }
704
705 void fib_add_ifaddr(struct in_ifaddr *ifa)
706 {
707 struct in_device *in_dev = ifa->ifa_dev;
708 struct net_device *dev = in_dev->dev;
709 struct in_ifaddr *prim = ifa;
710 __be32 mask = ifa->ifa_mask;
711 __be32 addr = ifa->ifa_local;
712 __be32 prefix = ifa->ifa_address&mask;
713
714 if (ifa->ifa_flags&IFA_F_SECONDARY) {
715 prim = inet_ifa_byprefix(in_dev, prefix, mask);
716 if (prim == NULL) {
717 printk(KERN_DEBUG "fib_add_ifaddr: bug: prim == NULL\n");
718 return;
719 }
720 }
721
722 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
723
724 if (!(dev->flags&IFF_UP))
725 return;
726
727 /* Add broadcast address, if it is explicitly assigned. */
728 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
729 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
730
731 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags&IFA_F_SECONDARY) &&
732 (prefix != addr || ifa->ifa_prefixlen < 32)) {
733 fib_magic(RTM_NEWROUTE, dev->flags&IFF_LOOPBACK ? RTN_LOCAL :
734 RTN_UNICAST, prefix, ifa->ifa_prefixlen, prim);
735
736 /* Add network specific broadcasts, when it takes a sense */
737 if (ifa->ifa_prefixlen < 31) {
738 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
739 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix|~mask, 32, prim);
740 }
741 }
742 }
743
744 static void fib_del_ifaddr(struct in_ifaddr *ifa)
745 {
746 struct in_device *in_dev = ifa->ifa_dev;
747 struct net_device *dev = in_dev->dev;
748 struct in_ifaddr *ifa1;
749 struct in_ifaddr *prim = ifa;
750 __be32 brd = ifa->ifa_address|~ifa->ifa_mask;
751 __be32 any = ifa->ifa_address&ifa->ifa_mask;
752 #define LOCAL_OK 1
753 #define BRD_OK 2
754 #define BRD0_OK 4
755 #define BRD1_OK 8
756 unsigned ok = 0;
757
758 if (!(ifa->ifa_flags&IFA_F_SECONDARY))
759 fib_magic(RTM_DELROUTE, dev->flags&IFF_LOOPBACK ? RTN_LOCAL :
760 RTN_UNICAST, any, ifa->ifa_prefixlen, prim);
761 else {
762 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
763 if (prim == NULL) {
764 printk(KERN_DEBUG "fib_del_ifaddr: bug: prim == NULL\n");
765 return;
766 }
767 }
768
769 /* Deletion is more complicated than add.
770 We should take care of not to delete too much :-)
771
772 Scan address list to be sure that addresses are really gone.
773 */
774
775 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
776 if (ifa->ifa_local == ifa1->ifa_local)
777 ok |= LOCAL_OK;
778 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
779 ok |= BRD_OK;
780 if (brd == ifa1->ifa_broadcast)
781 ok |= BRD1_OK;
782 if (any == ifa1->ifa_broadcast)
783 ok |= BRD0_OK;
784 }
785
786 if (!(ok&BRD_OK))
787 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
788 if (!(ok&BRD1_OK))
789 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
790 if (!(ok&BRD0_OK))
791 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
792 if (!(ok&LOCAL_OK)) {
793 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
794
795 /* Check, that this local address finally disappeared. */
796 if (inet_addr_type(&init_net, ifa->ifa_local) != RTN_LOCAL) {
797 /* And the last, but not the least thing.
798 We must flush stray FIB entries.
799
800 First of all, we scan fib_info list searching
801 for stray nexthop entries, then ignite fib_flush.
802 */
803 if (fib_sync_down(ifa->ifa_local, NULL, 0))
804 fib_flush(&init_net);
805 }
806 }
807 #undef LOCAL_OK
808 #undef BRD_OK
809 #undef BRD0_OK
810 #undef BRD1_OK
811 }
812
813 static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb )
814 {
815
816 struct fib_result res;
817 struct flowi fl = { .mark = frn->fl_mark,
818 .nl_u = { .ip4_u = { .daddr = frn->fl_addr,
819 .tos = frn->fl_tos,
820 .scope = frn->fl_scope } } };
821
822 #ifdef CONFIG_IP_MULTIPLE_TABLES
823 res.r = NULL;
824 #endif
825
826 frn->err = -ENOENT;
827 if (tb) {
828 local_bh_disable();
829
830 frn->tb_id = tb->tb_id;
831 frn->err = tb->tb_lookup(tb, &fl, &res);
832
833 if (!frn->err) {
834 frn->prefixlen = res.prefixlen;
835 frn->nh_sel = res.nh_sel;
836 frn->type = res.type;
837 frn->scope = res.scope;
838 fib_res_put(&res);
839 }
840 local_bh_enable();
841 }
842 }
843
844 static void nl_fib_input(struct sk_buff *skb)
845 {
846 struct net *net;
847 struct fib_result_nl *frn;
848 struct nlmsghdr *nlh;
849 struct fib_table *tb;
850 u32 pid;
851
852 net = skb->sk->sk_net;
853 nlh = nlmsg_hdr(skb);
854 if (skb->len < NLMSG_SPACE(0) || skb->len < nlh->nlmsg_len ||
855 nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*frn)))
856 return;
857
858 skb = skb_clone(skb, GFP_KERNEL);
859 if (skb == NULL)
860 return;
861 nlh = nlmsg_hdr(skb);
862
863 frn = (struct fib_result_nl *) NLMSG_DATA(nlh);
864 tb = fib_get_table(net, frn->tb_id_in);
865
866 nl_fib_lookup(frn, tb);
867
868 pid = NETLINK_CB(skb).pid; /* pid of sending process */
869 NETLINK_CB(skb).pid = 0; /* from kernel */
870 NETLINK_CB(skb).dst_group = 0; /* unicast */
871 netlink_unicast(net->ipv4.fibnl, skb, pid, MSG_DONTWAIT);
872 }
873
874 static int nl_fib_lookup_init(struct net *net)
875 {
876 struct sock *sk;
877 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, 0,
878 nl_fib_input, NULL, THIS_MODULE);
879 if (sk == NULL)
880 return -EAFNOSUPPORT;
881 /* Don't hold an extra reference on the namespace */
882 put_net(sk->sk_net);
883 net->ipv4.fibnl = sk;
884 return 0;
885 }
886
887 static void nl_fib_lookup_exit(struct net *net)
888 {
889 /* At the last minute lie and say this is a socket for the
890 * initial network namespace. So the socket will be safe to free.
891 */
892 net->ipv4.fibnl->sk_net = get_net(&init_net);
893 sock_put(net->ipv4.fibnl);
894 }
895
896 static void fib_disable_ip(struct net_device *dev, int force)
897 {
898 if (fib_sync_down(0, dev, force))
899 fib_flush(&init_net);
900 rt_cache_flush(0);
901 arp_ifdown(dev);
902 }
903
904 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
905 {
906 struct in_ifaddr *ifa = (struct in_ifaddr*)ptr;
907
908 switch (event) {
909 case NETDEV_UP:
910 fib_add_ifaddr(ifa);
911 #ifdef CONFIG_IP_ROUTE_MULTIPATH
912 fib_sync_up(ifa->ifa_dev->dev);
913 #endif
914 rt_cache_flush(-1);
915 break;
916 case NETDEV_DOWN:
917 fib_del_ifaddr(ifa);
918 if (ifa->ifa_dev->ifa_list == NULL) {
919 /* Last address was deleted from this interface.
920 Disable IP.
921 */
922 fib_disable_ip(ifa->ifa_dev->dev, 1);
923 } else {
924 rt_cache_flush(-1);
925 }
926 break;
927 }
928 return NOTIFY_DONE;
929 }
930
931 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
932 {
933 struct net_device *dev = ptr;
934 struct in_device *in_dev = __in_dev_get_rtnl(dev);
935
936 if (dev->nd_net != &init_net)
937 return NOTIFY_DONE;
938
939 if (event == NETDEV_UNREGISTER) {
940 fib_disable_ip(dev, 2);
941 return NOTIFY_DONE;
942 }
943
944 if (!in_dev)
945 return NOTIFY_DONE;
946
947 switch (event) {
948 case NETDEV_UP:
949 for_ifa(in_dev) {
950 fib_add_ifaddr(ifa);
951 } endfor_ifa(in_dev);
952 #ifdef CONFIG_IP_ROUTE_MULTIPATH
953 fib_sync_up(dev);
954 #endif
955 rt_cache_flush(-1);
956 break;
957 case NETDEV_DOWN:
958 fib_disable_ip(dev, 0);
959 break;
960 case NETDEV_CHANGEMTU:
961 case NETDEV_CHANGE:
962 rt_cache_flush(0);
963 break;
964 }
965 return NOTIFY_DONE;
966 }
967
968 static struct notifier_block fib_inetaddr_notifier = {
969 .notifier_call =fib_inetaddr_event,
970 };
971
972 static struct notifier_block fib_netdev_notifier = {
973 .notifier_call =fib_netdev_event,
974 };
975
976 static int __net_init ip_fib_net_init(struct net *net)
977 {
978 unsigned int i;
979
980 net->ipv4.fib_table_hash = kzalloc(
981 sizeof(struct hlist_head)*FIB_TABLE_HASHSZ, GFP_KERNEL);
982 if (net->ipv4.fib_table_hash == NULL)
983 return -ENOMEM;
984
985 for (i = 0; i < FIB_TABLE_HASHSZ; i++)
986 INIT_HLIST_HEAD(&net->ipv4.fib_table_hash[i]);
987
988 return fib4_rules_init(net);
989 }
990
991 static void __net_exit ip_fib_net_exit(struct net *net)
992 {
993 unsigned int i;
994
995 #ifdef CONFIG_IP_MULTIPLE_TABLES
996 fib4_rules_exit(net);
997 #endif
998
999 for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
1000 struct fib_table *tb;
1001 struct hlist_head *head;
1002 struct hlist_node *node, *tmp;
1003
1004 head = &net->ipv4.fib_table_hash[i];
1005 hlist_for_each_entry_safe(tb, node, tmp, head, tb_hlist) {
1006 hlist_del(node);
1007 tb->tb_flush(tb);
1008 kfree(tb);
1009 }
1010 }
1011 kfree(net->ipv4.fib_table_hash);
1012 }
1013
1014 static int __net_init fib_net_init(struct net *net)
1015 {
1016 int error;
1017
1018 error = 0;
1019 if (net != &init_net)
1020 goto out;
1021
1022 error = ip_fib_net_init(net);
1023 if (error < 0)
1024 goto out;
1025 error = nl_fib_lookup_init(net);
1026 if (error < 0)
1027 goto out_nlfl;
1028 error = fib_proc_init(net);
1029 if (error < 0)
1030 goto out_proc;
1031 out:
1032 return error;
1033
1034 out_proc:
1035 nl_fib_lookup_exit(net);
1036 out_nlfl:
1037 ip_fib_net_exit(net);
1038 goto out;
1039 }
1040
1041 static void __net_exit fib_net_exit(struct net *net)
1042 {
1043 fib_proc_exit(net);
1044 nl_fib_lookup_exit(net);
1045 ip_fib_net_exit(net);
1046 }
1047
1048 static struct pernet_operations fib_net_ops = {
1049 .init = fib_net_init,
1050 .exit = fib_net_exit,
1051 };
1052
1053 void __init ip_fib_init(void)
1054 {
1055 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL);
1056 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL);
1057 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib);
1058
1059 register_pernet_subsys(&fib_net_ops);
1060 register_netdevice_notifier(&fib_netdev_notifier);
1061 register_inetaddr_notifier(&fib_inetaddr_notifier);
1062 }
1063
1064 EXPORT_SYMBOL(inet_addr_type);
1065 EXPORT_SYMBOL(inet_dev_addr_type);
1066 EXPORT_SYMBOL(ip_dev_find);
Linux kernel - Deliverables
This page took 0.050797 seconds and 6 git commands to generate.