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fib_trie: use fls() instead of open coded loop
[net-next-2.6.git] / net / ipv4 / fib_frontend.c
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CommitLineData
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 <asm/uaccess.h>
18#include <asm/system.h>
19#include <linux/bitops.h>
20#include <linux/capability.h>
21#include <linux/types.h>
22#include <linux/kernel.h>
23#include <linux/mm.h>
24#include <linux/string.h>
25#include <linux/socket.h>
26#include <linux/sockios.h>
27#include <linux/errno.h>
28#include <linux/in.h>
29#include <linux/inet.h>
30#include <linux/inetdevice.h>
31#include <linux/netdevice.h>
32#include <linux/if_addr.h>
33#include <linux/if_arp.h>
34#include <linux/skbuff.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
48#ifndef CONFIG_IP_MULTIPLE_TABLES
49
50static int __net_init fib4_rules_init(struct net *net)
51{
52 struct fib_table *local_table, *main_table;
53
54 local_table = fib_hash_table(RT_TABLE_LOCAL);
55 if (local_table == NULL)
56 return -ENOMEM;
57
58 main_table = fib_hash_table(RT_TABLE_MAIN);
59 if (main_table == NULL)
60 goto fail;
61
62 hlist_add_head_rcu(&local_table->tb_hlist,
63 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]);
64 hlist_add_head_rcu(&main_table->tb_hlist,
65 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]);
66 return 0;
67
68fail:
69 kfree(local_table);
70 return -ENOMEM;
71}
72#else
73
74struct fib_table *fib_new_table(struct net *net, u32 id)
75{
76 struct fib_table *tb;
77 unsigned int h;
78
79 if (id == 0)
80 id = RT_TABLE_MAIN;
81 tb = fib_get_table(net, id);
82 if (tb)
83 return tb;
84
85 tb = fib_hash_table(id);
86 if (!tb)
87 return NULL;
88 h = id & (FIB_TABLE_HASHSZ - 1);
89 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
90 return tb;
91}
92
93struct fib_table *fib_get_table(struct net *net, u32 id)
94{
95 struct fib_table *tb;
96 struct hlist_node *node;
97 struct hlist_head *head;
98 unsigned int h;
99
100 if (id == 0)
101 id = RT_TABLE_MAIN;
102 h = id & (FIB_TABLE_HASHSZ - 1);
103
104 rcu_read_lock();
105 head = &net->ipv4.fib_table_hash[h];
106 hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
107 if (tb->tb_id == id) {
108 rcu_read_unlock();
109 return tb;
110 }
111 }
112 rcu_read_unlock();
113 return NULL;
114}
115#endif /* CONFIG_IP_MULTIPLE_TABLES */
116
117void fib_select_default(struct net *net,
118 const struct flowi *flp, struct fib_result *res)
119{
120 struct fib_table *tb;
121 int table = RT_TABLE_MAIN;
122#ifdef CONFIG_IP_MULTIPLE_TABLES
123 if (res->r == NULL || res->r->action != FR_ACT_TO_TBL)
124 return;
125 table = res->r->table;
126#endif
127 tb = fib_get_table(net, table);
128 if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
129 fib_table_select_default(tb, flp, res);
130}
131
132static void fib_flush(struct net *net)
133{
134 int flushed = 0;
135 struct fib_table *tb;
136 struct hlist_node *node;
137 struct hlist_head *head;
138 unsigned int h;
139
140 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
141 head = &net->ipv4.fib_table_hash[h];
142 hlist_for_each_entry(tb, node, head, tb_hlist)
143 flushed += fib_table_flush(tb);
144 }
145
146 if (flushed)
147 rt_cache_flush(net, -1);
148}
149
150/**
151 * __ip_dev_find - find the first device with a given source address.
152 * @net: the net namespace
153 * @addr: the source address
154 * @devref: if true, take a reference on the found device
155 *
156 * If a caller uses devref=false, it should be protected by RCU
157 */
158struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
159{
160 struct flowi fl = {
161 .nl_u = {
162 .ip4_u = {
163 .daddr = addr
164 }
165 },
166 .flags = FLOWI_FLAG_MATCH_ANY_IIF
167 };
168 struct fib_result res = { 0 };
169 struct net_device *dev = NULL;
170
171 rcu_read_lock();
172 if (fib_lookup(net, &fl, &res)) {
173 rcu_read_unlock();
174 return NULL;
175 }
176 if (res.type != RTN_LOCAL)
177 goto out;
178 dev = FIB_RES_DEV(res);
179
180 if (dev && devref)
181 dev_hold(dev);
182out:
183 rcu_read_unlock();
184 return dev;
185}
186EXPORT_SYMBOL(__ip_dev_find);
187
188/*
189 * Find address type as if only "dev" was present in the system. If
190 * on_dev is NULL then all interfaces are taken into consideration.
191 */
192static inline unsigned __inet_dev_addr_type(struct net *net,
193 const struct net_device *dev,
194 __be32 addr)
195{
196 struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } };
197 struct fib_result res;
198 unsigned ret = RTN_BROADCAST;
199 struct fib_table *local_table;
200
201 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
202 return RTN_BROADCAST;
203 if (ipv4_is_multicast(addr))
204 return RTN_MULTICAST;
205
206#ifdef CONFIG_IP_MULTIPLE_TABLES
207 res.r = NULL;
208#endif
209
210 local_table = fib_get_table(net, RT_TABLE_LOCAL);
211 if (local_table) {
212 ret = RTN_UNICAST;
213 rcu_read_lock();
214 if (!fib_table_lookup(local_table, &fl, &res, FIB_LOOKUP_NOREF)) {
215 if (!dev || dev == res.fi->fib_dev)
216 ret = res.type;
217 }
218 rcu_read_unlock();
219 }
220 return ret;
221}
222
223unsigned int inet_addr_type(struct net *net, __be32 addr)
224{
225 return __inet_dev_addr_type(net, NULL, addr);
226}
227EXPORT_SYMBOL(inet_addr_type);
228
229unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
230 __be32 addr)
231{
232 return __inet_dev_addr_type(net, dev, addr);
233}
234EXPORT_SYMBOL(inet_dev_addr_type);
235
236/* Given (packet source, input interface) and optional (dst, oif, tos):
237 * - (main) check, that source is valid i.e. not broadcast or our local
238 * address.
239 * - figure out what "logical" interface this packet arrived
240 * and calculate "specific destination" address.
241 * - check, that packet arrived from expected physical interface.
242 * called with rcu_read_lock()
243 */
244int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
245 struct net_device *dev, __be32 *spec_dst,
246 u32 *itag, u32 mark)
247{
248 struct in_device *in_dev;
249 struct flowi fl = {
250 .nl_u = {
251 .ip4_u = {
252 .daddr = src,
253 .saddr = dst,
254 .tos = tos
255 }
256 },
257 .mark = mark,
258 .iif = oif
259 };
260 struct fib_result res;
261 int no_addr, rpf, accept_local;
262 bool dev_match;
263 int ret;
264 struct net *net;
265
266 no_addr = rpf = accept_local = 0;
267 in_dev = __in_dev_get_rcu(dev);
268 if (in_dev) {
269 no_addr = in_dev->ifa_list == NULL;
270 rpf = IN_DEV_RPFILTER(in_dev);
271 accept_local = IN_DEV_ACCEPT_LOCAL(in_dev);
272 if (mark && !IN_DEV_SRC_VMARK(in_dev))
273 fl.mark = 0;
274 }
275
276 if (in_dev == NULL)
277 goto e_inval;
278
279 net = dev_net(dev);
280 if (fib_lookup(net, &fl, &res))
281 goto last_resort;
282 if (res.type != RTN_UNICAST) {
283 if (res.type != RTN_LOCAL || !accept_local)
284 goto e_inval;
285 }
286 *spec_dst = FIB_RES_PREFSRC(res);
287 fib_combine_itag(itag, &res);
288 dev_match = false;
289
290#ifdef CONFIG_IP_ROUTE_MULTIPATH
291 for (ret = 0; ret < res.fi->fib_nhs; ret++) {
292 struct fib_nh *nh = &res.fi->fib_nh[ret];
293
294 if (nh->nh_dev == dev) {
295 dev_match = true;
296 break;
297 }
298 }
299#else
300 if (FIB_RES_DEV(res) == dev)
301 dev_match = true;
302#endif
303 if (dev_match) {
304 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
305 return ret;
306 }
307 if (no_addr)
308 goto last_resort;
309 if (rpf == 1)
310 goto e_rpf;
311 fl.oif = dev->ifindex;
312
313 ret = 0;
314 if (fib_lookup(net, &fl, &res) == 0) {
315 if (res.type == RTN_UNICAST) {
316 *spec_dst = FIB_RES_PREFSRC(res);
317 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
318 }
319 }
320 return ret;
321
322last_resort:
323 if (rpf)
324 goto e_rpf;
325 *spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
326 *itag = 0;
327 return 0;
328
329e_inval:
330 return -EINVAL;
331e_rpf:
332 return -EXDEV;
333}
334
335static inline __be32 sk_extract_addr(struct sockaddr *addr)
336{
337 return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
338}
339
340static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
341{
342 struct nlattr *nla;
343
344 nla = (struct nlattr *) ((char *) mx + len);
345 nla->nla_type = type;
346 nla->nla_len = nla_attr_size(4);
347 *(u32 *) nla_data(nla) = value;
348
349 return len + nla_total_size(4);
350}
351
352static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
353 struct fib_config *cfg)
354{
355 __be32 addr;
356 int plen;
357
358 memset(cfg, 0, sizeof(*cfg));
359 cfg->fc_nlinfo.nl_net = net;
360
361 if (rt->rt_dst.sa_family != AF_INET)
362 return -EAFNOSUPPORT;
363
364 /*
365 * Check mask for validity:
366 * a) it must be contiguous.
367 * b) destination must have all host bits clear.
368 * c) if application forgot to set correct family (AF_INET),
369 * reject request unless it is absolutely clear i.e.
370 * both family and mask are zero.
371 */
372 plen = 32;
373 addr = sk_extract_addr(&rt->rt_dst);
374 if (!(rt->rt_flags & RTF_HOST)) {
375 __be32 mask = sk_extract_addr(&rt->rt_genmask);
376
377 if (rt->rt_genmask.sa_family != AF_INET) {
378 if (mask || rt->rt_genmask.sa_family)
379 return -EAFNOSUPPORT;
380 }
381
382 if (bad_mask(mask, addr))
383 return -EINVAL;
384
385 plen = inet_mask_len(mask);
386 }
387
388 cfg->fc_dst_len = plen;
389 cfg->fc_dst = addr;
390
391 if (cmd != SIOCDELRT) {
392 cfg->fc_nlflags = NLM_F_CREATE;
393 cfg->fc_protocol = RTPROT_BOOT;
394 }
395
396 if (rt->rt_metric)
397 cfg->fc_priority = rt->rt_metric - 1;
398
399 if (rt->rt_flags & RTF_REJECT) {
400 cfg->fc_scope = RT_SCOPE_HOST;
401 cfg->fc_type = RTN_UNREACHABLE;
402 return 0;
403 }
404
405 cfg->fc_scope = RT_SCOPE_NOWHERE;
406 cfg->fc_type = RTN_UNICAST;
407
408 if (rt->rt_dev) {
409 char *colon;
410 struct net_device *dev;
411 char devname[IFNAMSIZ];
412
413 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
414 return -EFAULT;
415
416 devname[IFNAMSIZ-1] = 0;
417 colon = strchr(devname, ':');
418 if (colon)
419 *colon = 0;
420 dev = __dev_get_by_name(net, devname);
421 if (!dev)
422 return -ENODEV;
423 cfg->fc_oif = dev->ifindex;
424 if (colon) {
425 struct in_ifaddr *ifa;
426 struct in_device *in_dev = __in_dev_get_rtnl(dev);
427 if (!in_dev)
428 return -ENODEV;
429 *colon = ':';
430 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
431 if (strcmp(ifa->ifa_label, devname) == 0)
432 break;
433 if (ifa == NULL)
434 return -ENODEV;
435 cfg->fc_prefsrc = ifa->ifa_local;
436 }
437 }
438
439 addr = sk_extract_addr(&rt->rt_gateway);
440 if (rt->rt_gateway.sa_family == AF_INET && addr) {
441 cfg->fc_gw = addr;
442 if (rt->rt_flags & RTF_GATEWAY &&
443 inet_addr_type(net, addr) == RTN_UNICAST)
444 cfg->fc_scope = RT_SCOPE_UNIVERSE;
445 }
446
447 if (cmd == SIOCDELRT)
448 return 0;
449
450 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
451 return -EINVAL;
452
453 if (cfg->fc_scope == RT_SCOPE_NOWHERE)
454 cfg->fc_scope = RT_SCOPE_LINK;
455
456 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
457 struct nlattr *mx;
458 int len = 0;
459
460 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
461 if (mx == NULL)
462 return -ENOMEM;
463
464 if (rt->rt_flags & RTF_MTU)
465 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
466
467 if (rt->rt_flags & RTF_WINDOW)
468 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
469
470 if (rt->rt_flags & RTF_IRTT)
471 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
472
473 cfg->fc_mx = mx;
474 cfg->fc_mx_len = len;
475 }
476
477 return 0;
478}
479
480/*
481 * Handle IP routing ioctl calls.
482 * These are used to manipulate the routing tables
483 */
484int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
485{
486 struct fib_config cfg;
487 struct rtentry rt;
488 int err;
489
490 switch (cmd) {
491 case SIOCADDRT: /* Add a route */
492 case SIOCDELRT: /* Delete a route */
493 if (!capable(CAP_NET_ADMIN))
494 return -EPERM;
495
496 if (copy_from_user(&rt, arg, sizeof(rt)))
497 return -EFAULT;
498
499 rtnl_lock();
500 err = rtentry_to_fib_config(net, cmd, &rt, &cfg);
501 if (err == 0) {
502 struct fib_table *tb;
503
504 if (cmd == SIOCDELRT) {
505 tb = fib_get_table(net, cfg.fc_table);
506 if (tb)
507 err = fib_table_delete(tb, &cfg);
508 else
509 err = -ESRCH;
510 } else {
511 tb = fib_new_table(net, cfg.fc_table);
512 if (tb)
513 err = fib_table_insert(tb, &cfg);
514 else
515 err = -ENOBUFS;
516 }
517
518 /* allocated by rtentry_to_fib_config() */
519 kfree(cfg.fc_mx);
520 }
521 rtnl_unlock();
522 return err;
523 }
524 return -EINVAL;
525}
526
527const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
528 [RTA_DST] = { .type = NLA_U32 },
529 [RTA_SRC] = { .type = NLA_U32 },
530 [RTA_IIF] = { .type = NLA_U32 },
531 [RTA_OIF] = { .type = NLA_U32 },
532 [RTA_GATEWAY] = { .type = NLA_U32 },
533 [RTA_PRIORITY] = { .type = NLA_U32 },
534 [RTA_PREFSRC] = { .type = NLA_U32 },
535 [RTA_METRICS] = { .type = NLA_NESTED },
536 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
537 [RTA_FLOW] = { .type = NLA_U32 },
538};
539
540static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
541 struct nlmsghdr *nlh, struct fib_config *cfg)
542{
543 struct nlattr *attr;
544 int err, remaining;
545 struct rtmsg *rtm;
546
547 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
548 if (err < 0)
549 goto errout;
550
551 memset(cfg, 0, sizeof(*cfg));
552
553 rtm = nlmsg_data(nlh);
554 cfg->fc_dst_len = rtm->rtm_dst_len;
555 cfg->fc_tos = rtm->rtm_tos;
556 cfg->fc_table = rtm->rtm_table;
557 cfg->fc_protocol = rtm->rtm_protocol;
558 cfg->fc_scope = rtm->rtm_scope;
559 cfg->fc_type = rtm->rtm_type;
560 cfg->fc_flags = rtm->rtm_flags;
561 cfg->fc_nlflags = nlh->nlmsg_flags;
562
563 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
564 cfg->fc_nlinfo.nlh = nlh;
565 cfg->fc_nlinfo.nl_net = net;
566
567 if (cfg->fc_type > RTN_MAX) {
568 err = -EINVAL;
569 goto errout;
570 }
571
572 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
573 switch (nla_type(attr)) {
574 case RTA_DST:
575 cfg->fc_dst = nla_get_be32(attr);
576 break;
577 case RTA_OIF:
578 cfg->fc_oif = nla_get_u32(attr);
579 break;
580 case RTA_GATEWAY:
581 cfg->fc_gw = nla_get_be32(attr);
582 break;
583 case RTA_PRIORITY:
584 cfg->fc_priority = nla_get_u32(attr);
585 break;
586 case RTA_PREFSRC:
587 cfg->fc_prefsrc = nla_get_be32(attr);
588 break;
589 case RTA_METRICS:
590 cfg->fc_mx = nla_data(attr);
591 cfg->fc_mx_len = nla_len(attr);
592 break;
593 case RTA_MULTIPATH:
594 cfg->fc_mp = nla_data(attr);
595 cfg->fc_mp_len = nla_len(attr);
596 break;
597 case RTA_FLOW:
598 cfg->fc_flow = nla_get_u32(attr);
599 break;
600 case RTA_TABLE:
601 cfg->fc_table = nla_get_u32(attr);
602 break;
603 }
604 }
605
606 return 0;
607errout:
608 return err;
609}
610
611static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
612{
613 struct net *net = sock_net(skb->sk);
614 struct fib_config cfg;
615 struct fib_table *tb;
616 int err;
617
618 err = rtm_to_fib_config(net, skb, nlh, &cfg);
619 if (err < 0)
620 goto errout;
621
622 tb = fib_get_table(net, cfg.fc_table);
623 if (tb == NULL) {
624 err = -ESRCH;
625 goto errout;
626 }
627
628 err = fib_table_delete(tb, &cfg);
629errout:
630 return err;
631}
632
633static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
634{
635 struct net *net = sock_net(skb->sk);
636 struct fib_config cfg;
637 struct fib_table *tb;
638 int err;
639
640 err = rtm_to_fib_config(net, skb, nlh, &cfg);
641 if (err < 0)
642 goto errout;
643
644 tb = fib_new_table(net, cfg.fc_table);
645 if (tb == NULL) {
646 err = -ENOBUFS;
647 goto errout;
648 }
649
650 err = fib_table_insert(tb, &cfg);
651errout:
652 return err;
653}
654
655static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
656{
657 struct net *net = sock_net(skb->sk);
658 unsigned int h, s_h;
659 unsigned int e = 0, s_e;
660 struct fib_table *tb;
661 struct hlist_node *node;
662 struct hlist_head *head;
663 int dumped = 0;
664
665 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
666 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
667 return ip_rt_dump(skb, cb);
668
669 s_h = cb->args[0];
670 s_e = cb->args[1];
671
672 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
673 e = 0;
674 head = &net->ipv4.fib_table_hash[h];
675 hlist_for_each_entry(tb, node, head, tb_hlist) {
676 if (e < s_e)
677 goto next;
678 if (dumped)
679 memset(&cb->args[2], 0, sizeof(cb->args) -
680 2 * sizeof(cb->args[0]));
681 if (fib_table_dump(tb, skb, cb) < 0)
682 goto out;
683 dumped = 1;
684next:
685 e++;
686 }
687 }
688out:
689 cb->args[1] = e;
690 cb->args[0] = h;
691
692 return skb->len;
693}
694
695/* Prepare and feed intra-kernel routing request.
696 * Really, it should be netlink message, but :-( netlink
697 * can be not configured, so that we feed it directly
698 * to fib engine. It is legal, because all events occur
699 * only when netlink is already locked.
700 */
701static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
702{
703 struct net *net = dev_net(ifa->ifa_dev->dev);
704 struct fib_table *tb;
705 struct fib_config cfg = {
706 .fc_protocol = RTPROT_KERNEL,
707 .fc_type = type,
708 .fc_dst = dst,
709 .fc_dst_len = dst_len,
710 .fc_prefsrc = ifa->ifa_local,
711 .fc_oif = ifa->ifa_dev->dev->ifindex,
712 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
713 .fc_nlinfo = {
714 .nl_net = net,
715 },
716 };
717
718 if (type == RTN_UNICAST)
719 tb = fib_new_table(net, RT_TABLE_MAIN);
720 else
721 tb = fib_new_table(net, RT_TABLE_LOCAL);
722
723 if (tb == NULL)
724 return;
725
726 cfg.fc_table = tb->tb_id;
727
728 if (type != RTN_LOCAL)
729 cfg.fc_scope = RT_SCOPE_LINK;
730 else
731 cfg.fc_scope = RT_SCOPE_HOST;
732
733 if (cmd == RTM_NEWROUTE)
734 fib_table_insert(tb, &cfg);
735 else
736 fib_table_delete(tb, &cfg);
737}
738
739void fib_add_ifaddr(struct in_ifaddr *ifa)
740{
741 struct in_device *in_dev = ifa->ifa_dev;
742 struct net_device *dev = in_dev->dev;
743 struct in_ifaddr *prim = ifa;
744 __be32 mask = ifa->ifa_mask;
745 __be32 addr = ifa->ifa_local;
746 __be32 prefix = ifa->ifa_address & mask;
747
748 if (ifa->ifa_flags & IFA_F_SECONDARY) {
749 prim = inet_ifa_byprefix(in_dev, prefix, mask);
750 if (prim == NULL) {
751 printk(KERN_WARNING "fib_add_ifaddr: bug: prim == NULL\n");
752 return;
753 }
754 }
755
756 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
757
758 if (!(dev->flags & IFF_UP))
759 return;
760
761 /* Add broadcast address, if it is explicitly assigned. */
762 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
763 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
764
765 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
766 (prefix != addr || ifa->ifa_prefixlen < 32)) {
767 fib_magic(RTM_NEWROUTE,
768 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
769 prefix, ifa->ifa_prefixlen, prim);
770
771 /* Add network specific broadcasts, when it takes a sense */
772 if (ifa->ifa_prefixlen < 31) {
773 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
774 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
775 32, prim);
776 }
777 }
778}
779
780static void fib_del_ifaddr(struct in_ifaddr *ifa)
781{
782 struct in_device *in_dev = ifa->ifa_dev;
783 struct net_device *dev = in_dev->dev;
784 struct in_ifaddr *ifa1;
785 struct in_ifaddr *prim = ifa;
786 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
787 __be32 any = ifa->ifa_address & ifa->ifa_mask;
788#define LOCAL_OK 1
789#define BRD_OK 2
790#define BRD0_OK 4
791#define BRD1_OK 8
792 unsigned ok = 0;
793
794 if (!(ifa->ifa_flags & IFA_F_SECONDARY))
795 fib_magic(RTM_DELROUTE,
796 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
797 any, ifa->ifa_prefixlen, prim);
798 else {
799 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
800 if (prim == NULL) {
801 printk(KERN_WARNING "fib_del_ifaddr: bug: prim == NULL\n");
802 return;
803 }
804 }
805
806 /* Deletion is more complicated than add.
807 * We should take care of not to delete too much :-)
808 *
809 * Scan address list to be sure that addresses are really gone.
810 */
811
812 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
813 if (ifa->ifa_local == ifa1->ifa_local)
814 ok |= LOCAL_OK;
815 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
816 ok |= BRD_OK;
817 if (brd == ifa1->ifa_broadcast)
818 ok |= BRD1_OK;
819 if (any == ifa1->ifa_broadcast)
820 ok |= BRD0_OK;
821 }
822
823 if (!(ok & BRD_OK))
824 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
825 if (!(ok & BRD1_OK))
826 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
827 if (!(ok & BRD0_OK))
828 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
829 if (!(ok & LOCAL_OK)) {
830 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
831
832 /* Check, that this local address finally disappeared. */
833 if (inet_addr_type(dev_net(dev), ifa->ifa_local) != RTN_LOCAL) {
834 /* And the last, but not the least thing.
835 * We must flush stray FIB entries.
836 *
837 * First of all, we scan fib_info list searching
838 * for stray nexthop entries, then ignite fib_flush.
839 */
840 if (fib_sync_down_addr(dev_net(dev), ifa->ifa_local))
841 fib_flush(dev_net(dev));
842 }
843 }
844#undef LOCAL_OK
845#undef BRD_OK
846#undef BRD0_OK
847#undef BRD1_OK
848}
849
850static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb)
851{
852
853 struct fib_result res;
854 struct flowi fl = {
855 .mark = frn->fl_mark,
856 .nl_u = {
857 .ip4_u = {
858 .daddr = frn->fl_addr,
859 .tos = frn->fl_tos,
860 .scope = frn->fl_scope
861 }
862 }
863 };
864
865#ifdef CONFIG_IP_MULTIPLE_TABLES
866 res.r = NULL;
867#endif
868
869 frn->err = -ENOENT;
870 if (tb) {
871 local_bh_disable();
872
873 frn->tb_id = tb->tb_id;
874 rcu_read_lock();
875 frn->err = fib_table_lookup(tb, &fl, &res, FIB_LOOKUP_NOREF);
876
877 if (!frn->err) {
878 frn->prefixlen = res.prefixlen;
879 frn->nh_sel = res.nh_sel;
880 frn->type = res.type;
881 frn->scope = res.scope;
882 }
883 rcu_read_unlock();
884 local_bh_enable();
885 }
886}
887
888static void nl_fib_input(struct sk_buff *skb)
889{
890 struct net *net;
891 struct fib_result_nl *frn;
892 struct nlmsghdr *nlh;
893 struct fib_table *tb;
894 u32 pid;
895
896 net = sock_net(skb->sk);
897 nlh = nlmsg_hdr(skb);
898 if (skb->len < NLMSG_SPACE(0) || skb->len < nlh->nlmsg_len ||
899 nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*frn)))
900 return;
901
902 skb = skb_clone(skb, GFP_KERNEL);
903 if (skb == NULL)
904 return;
905 nlh = nlmsg_hdr(skb);
906
907 frn = (struct fib_result_nl *) NLMSG_DATA(nlh);
908 tb = fib_get_table(net, frn->tb_id_in);
909
910 nl_fib_lookup(frn, tb);
911
912 pid = NETLINK_CB(skb).pid; /* pid of sending process */
913 NETLINK_CB(skb).pid = 0; /* from kernel */
914 NETLINK_CB(skb).dst_group = 0; /* unicast */
915 netlink_unicast(net->ipv4.fibnl, skb, pid, MSG_DONTWAIT);
916}
917
918static int __net_init nl_fib_lookup_init(struct net *net)
919{
920 struct sock *sk;
921 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, 0,
922 nl_fib_input, NULL, THIS_MODULE);
923 if (sk == NULL)
924 return -EAFNOSUPPORT;
925 net->ipv4.fibnl = sk;
926 return 0;
927}
928
929static void nl_fib_lookup_exit(struct net *net)
930{
931 netlink_kernel_release(net->ipv4.fibnl);
932 net->ipv4.fibnl = NULL;
933}
934
935static void fib_disable_ip(struct net_device *dev, int force, int delay)
936{
937 if (fib_sync_down_dev(dev, force))
938 fib_flush(dev_net(dev));
939 rt_cache_flush(dev_net(dev), delay);
940 arp_ifdown(dev);
941}
942
943static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
944{
945 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
946 struct net_device *dev = ifa->ifa_dev->dev;
947
948 switch (event) {
949 case NETDEV_UP:
950 fib_add_ifaddr(ifa);
951#ifdef CONFIG_IP_ROUTE_MULTIPATH
952 fib_sync_up(dev);
953#endif
954 rt_cache_flush(dev_net(dev), -1);
955 break;
956 case NETDEV_DOWN:
957 fib_del_ifaddr(ifa);
958 if (ifa->ifa_dev->ifa_list == NULL) {
959 /* Last address was deleted from this interface.
960 * Disable IP.
961 */
962 fib_disable_ip(dev, 1, 0);
963 } else {
964 rt_cache_flush(dev_net(dev), -1);
965 }
966 break;
967 }
968 return NOTIFY_DONE;
969}
970
971static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
972{
973 struct net_device *dev = ptr;
974 struct in_device *in_dev = __in_dev_get_rtnl(dev);
975
976 if (event == NETDEV_UNREGISTER) {
977 fib_disable_ip(dev, 2, -1);
978 return NOTIFY_DONE;
979 }
980
981 if (!in_dev)
982 return NOTIFY_DONE;
983
984 switch (event) {
985 case NETDEV_UP:
986 for_ifa(in_dev) {
987 fib_add_ifaddr(ifa);
988 } endfor_ifa(in_dev);
989#ifdef CONFIG_IP_ROUTE_MULTIPATH
990 fib_sync_up(dev);
991#endif
992 rt_cache_flush(dev_net(dev), -1);
993 break;
994 case NETDEV_DOWN:
995 fib_disable_ip(dev, 0, 0);
996 break;
997 case NETDEV_CHANGEMTU:
998 case NETDEV_CHANGE:
999 rt_cache_flush(dev_net(dev), 0);
1000 break;
1001 case NETDEV_UNREGISTER_BATCH:
1002 rt_cache_flush_batch();
1003 break;
1004 }
1005 return NOTIFY_DONE;
1006}
1007
1008static struct notifier_block fib_inetaddr_notifier = {
1009 .notifier_call = fib_inetaddr_event,
1010};
1011
1012static struct notifier_block fib_netdev_notifier = {
1013 .notifier_call = fib_netdev_event,
1014};
1015
1016static int __net_init ip_fib_net_init(struct net *net)
1017{
1018 int err;
1019 unsigned int i;
1020
1021 net->ipv4.fib_table_hash = kzalloc(
1022 sizeof(struct hlist_head)*FIB_TABLE_HASHSZ, GFP_KERNEL);
1023 if (net->ipv4.fib_table_hash == NULL)
1024 return -ENOMEM;
1025
1026 for (i = 0; i < FIB_TABLE_HASHSZ; i++)
1027 INIT_HLIST_HEAD(&net->ipv4.fib_table_hash[i]);
1028
1029 err = fib4_rules_init(net);
1030 if (err < 0)
1031 goto fail;
1032 return 0;
1033
1034fail:
1035 kfree(net->ipv4.fib_table_hash);
1036 return err;
1037}
1038
1039static void ip_fib_net_exit(struct net *net)
1040{
1041 unsigned int i;
1042
1043#ifdef CONFIG_IP_MULTIPLE_TABLES
1044 fib4_rules_exit(net);
1045#endif
1046
1047 for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
1048 struct fib_table *tb;
1049 struct hlist_head *head;
1050 struct hlist_node *node, *tmp;
1051
1052 head = &net->ipv4.fib_table_hash[i];
1053 hlist_for_each_entry_safe(tb, node, tmp, head, tb_hlist) {
1054 hlist_del(node);
1055 fib_table_flush(tb);
1056 kfree(tb);
1057 }
1058 }
1059 kfree(net->ipv4.fib_table_hash);
1060}
1061
1062static int __net_init fib_net_init(struct net *net)
1063{
1064 int error;
1065
1066 error = ip_fib_net_init(net);
1067 if (error < 0)
1068 goto out;
1069 error = nl_fib_lookup_init(net);
1070 if (error < 0)
1071 goto out_nlfl;
1072 error = fib_proc_init(net);
1073 if (error < 0)
1074 goto out_proc;
1075out:
1076 return error;
1077
1078out_proc:
1079 nl_fib_lookup_exit(net);
1080out_nlfl:
1081 ip_fib_net_exit(net);
1082 goto out;
1083}
1084
1085static void __net_exit fib_net_exit(struct net *net)
1086{
1087 fib_proc_exit(net);
1088 nl_fib_lookup_exit(net);
1089 ip_fib_net_exit(net);
1090}
1091
1092static struct pernet_operations fib_net_ops = {
1093 .init = fib_net_init,
1094 .exit = fib_net_exit,
1095};
1096
1097void __init ip_fib_init(void)
1098{
1099 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL);
1100 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL);
1101 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib);
1102
1103 register_pernet_subsys(&fib_net_ops);
1104 register_netdevice_notifier(&fib_netdev_notifier);
1105 register_inetaddr_notifier(&fib_inetaddr_notifier);
1106
1107 fib_hash_init();
1108}
Clone of davem's net-next-2.6 tree