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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * IPv4 Forwarding Information Base: semantics.
7 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/bitops.h>
18#include <linux/types.h>
19#include <linux/kernel.h>
20#include <linux/jiffies.h>
21#include <linux/mm.h>
22#include <linux/string.h>
23#include <linux/socket.h>
24#include <linux/sockios.h>
25#include <linux/errno.h>
26#include <linux/in.h>
27#include <linux/inet.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020028#include <linux/inetdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/netdevice.h>
30#include <linux/if_arp.h>
31#include <linux/proc_fs.h>
32#include <linux/skbuff.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/init.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090034#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020036#include <net/arp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <net/ip.h>
38#include <net/protocol.h>
39#include <net/route.h>
40#include <net/tcp.h>
41#include <net/sock.h>
42#include <net/ip_fib.h>
Thomas Graff21c7bc2006-08-15 00:34:17 -070043#include <net/netlink.h>
Thomas Graf4e902c52006-08-17 18:14:52 -070044#include <net/nexthop.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
46#include "fib_lookup.h"
47
Stephen Hemminger832b4c52006-08-29 16:48:09 -070048static DEFINE_SPINLOCK(fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049static struct hlist_head *fib_info_hash;
50static struct hlist_head *fib_info_laddrhash;
David S. Miller123b9732011-02-01 15:34:21 -080051static unsigned int fib_info_hash_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -070052static unsigned int fib_info_cnt;
53
54#define DEVINDEX_HASHBITS 8
55#define DEVINDEX_HASHSIZE (1U << DEVINDEX_HASHBITS)
56static struct hlist_head fib_info_devhash[DEVINDEX_HASHSIZE];
57
58#ifdef CONFIG_IP_ROUTE_MULTIPATH
59
60static DEFINE_SPINLOCK(fib_multipath_lock);
61
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000062#define for_nexthops(fi) { \
63 int nhsel; const struct fib_nh *nh; \
64 for (nhsel = 0, nh = (fi)->fib_nh; \
65 nhsel < (fi)->fib_nhs; \
66 nh++, nhsel++)
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000068#define change_nexthops(fi) { \
69 int nhsel; struct fib_nh *nexthop_nh; \
70 for (nhsel = 0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \
71 nhsel < (fi)->fib_nhs; \
72 nexthop_nh++, nhsel++)
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74#else /* CONFIG_IP_ROUTE_MULTIPATH */
75
76/* Hope, that gcc will optimize it to get rid of dummy loop */
77
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000078#define for_nexthops(fi) { \
79 int nhsel; const struct fib_nh *nh = (fi)->fib_nh; \
80 for (nhsel = 0; nhsel < 1; nhsel++)
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000082#define change_nexthops(fi) { \
83 int nhsel; \
84 struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \
85 for (nhsel = 0; nhsel < 1; nhsel++)
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
87#endif /* CONFIG_IP_ROUTE_MULTIPATH */
88
89#define endfor_nexthops(fi) }
90
91
David S. Miller3be06862011-03-07 15:01:10 -080092const struct fib_prop fib_props[RTN_MAX + 1] = {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000093 [RTN_UNSPEC] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 .error = 0,
95 .scope = RT_SCOPE_NOWHERE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000096 },
97 [RTN_UNICAST] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 .error = 0,
99 .scope = RT_SCOPE_UNIVERSE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000100 },
101 [RTN_LOCAL] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 .error = 0,
103 .scope = RT_SCOPE_HOST,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000104 },
105 [RTN_BROADCAST] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 .error = 0,
107 .scope = RT_SCOPE_LINK,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000108 },
109 [RTN_ANYCAST] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 .error = 0,
111 .scope = RT_SCOPE_LINK,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000112 },
113 [RTN_MULTICAST] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 .error = 0,
115 .scope = RT_SCOPE_UNIVERSE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000116 },
117 [RTN_BLACKHOLE] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 .error = -EINVAL,
119 .scope = RT_SCOPE_UNIVERSE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000120 },
121 [RTN_UNREACHABLE] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 .error = -EHOSTUNREACH,
123 .scope = RT_SCOPE_UNIVERSE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000124 },
125 [RTN_PROHIBIT] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 .error = -EACCES,
127 .scope = RT_SCOPE_UNIVERSE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000128 },
129 [RTN_THROW] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 .error = -EAGAIN,
131 .scope = RT_SCOPE_UNIVERSE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000132 },
133 [RTN_NAT] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 .error = -EINVAL,
135 .scope = RT_SCOPE_NOWHERE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000136 },
137 [RTN_XRESOLVE] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 .error = -EINVAL,
139 .scope = RT_SCOPE_NOWHERE,
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000140 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141};
142
David S. Millerc5038a82012-07-31 15:02:02 -0700143static void rt_fibinfo_free(struct rtable __rcu **rtp)
Eric Dumazet54764bb2012-07-31 01:08:23 +0000144{
145 struct rtable *rt = rcu_dereference_protected(*rtp, 1);
146
147 if (!rt)
148 return;
149
150 /* Not even needed : RCU_INIT_POINTER(*rtp, NULL);
151 * because we waited an RCU grace period before calling
152 * free_fib_info_rcu()
153 */
154
155 dst_free(&rt->dst);
156}
157
David S. Millerc5038a82012-07-31 15:02:02 -0700158static void free_nh_exceptions(struct fib_nh *nh)
159{
160 struct fnhe_hash_bucket *hash = nh->nh_exceptions;
161 int i;
162
163 for (i = 0; i < FNHE_HASH_SIZE; i++) {
164 struct fib_nh_exception *fnhe;
165
166 fnhe = rcu_dereference_protected(hash[i].chain, 1);
167 while (fnhe) {
168 struct fib_nh_exception *next;
169
170 next = rcu_dereference_protected(fnhe->fnhe_next, 1);
171
Timo Teräs2ffae992013-06-27 10:27:05 +0300172 rt_fibinfo_free(&fnhe->fnhe_rth_input);
173 rt_fibinfo_free(&fnhe->fnhe_rth_output);
David S. Millerc5038a82012-07-31 15:02:02 -0700174
175 kfree(fnhe);
176
177 fnhe = next;
178 }
179 }
180 kfree(hash);
181}
182
183static void rt_fibinfo_free_cpus(struct rtable __rcu * __percpu *rtp)
Eric Dumazetd26b3a72012-07-31 05:45:30 +0000184{
185 int cpu;
186
187 if (!rtp)
188 return;
189
190 for_each_possible_cpu(cpu) {
191 struct rtable *rt;
192
193 rt = rcu_dereference_protected(*per_cpu_ptr(rtp, cpu), 1);
194 if (rt)
195 dst_free(&rt->dst);
196 }
197 free_percpu(rtp);
198}
199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200/* Release a nexthop info record */
Yan, Zheng19c1ea12011-09-04 20:24:20 +0000201static void free_fib_info_rcu(struct rcu_head *head)
202{
203 struct fib_info *fi = container_of(head, struct fib_info, rcu);
204
Yanmin Zhange49cc0d2012-05-23 15:39:45 +0000205 change_nexthops(fi) {
206 if (nexthop_nh->nh_dev)
207 dev_put(nexthop_nh->nh_dev);
David S. Miller4895c772012-07-17 04:19:00 -0700208 if (nexthop_nh->nh_exceptions)
209 free_nh_exceptions(nexthop_nh);
David S. Millerc5038a82012-07-31 15:02:02 -0700210 rt_fibinfo_free_cpus(nexthop_nh->nh_pcpu_rth_output);
211 rt_fibinfo_free(&nexthop_nh->nh_rth_input);
Yanmin Zhange49cc0d2012-05-23 15:39:45 +0000212 } endfor_nexthops(fi);
213
214 release_net(fi->fib_net);
Yan, Zheng19c1ea12011-09-04 20:24:20 +0000215 if (fi->fib_metrics != (u32 *) dst_default_metrics)
216 kfree(fi->fib_metrics);
217 kfree(fi);
218}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219
220void free_fib_info(struct fib_info *fi)
221{
222 if (fi->fib_dead == 0) {
Joe Perches058bd4d2012-03-11 18:36:11 +0000223 pr_warn("Freeing alive fib_info %p\n", fi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 return;
225 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 fib_info_cnt--;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700227#ifdef CONFIG_IP_ROUTE_CLASSID
228 change_nexthops(fi) {
229 if (nexthop_nh->nh_tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700230 fi->fib_net->ipv4.fib_num_tclassid_users--;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700231 } endfor_nexthops(fi);
232#endif
Yan, Zheng19c1ea12011-09-04 20:24:20 +0000233 call_rcu(&fi->rcu, free_fib_info_rcu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234}
235
236void fib_release_info(struct fib_info *fi)
237{
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700238 spin_lock_bh(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 if (fi && --fi->fib_treeref == 0) {
240 hlist_del(&fi->fib_hash);
241 if (fi->fib_prefsrc)
242 hlist_del(&fi->fib_lhash);
243 change_nexthops(fi) {
David S. Miller71fceff2010-01-15 01:16:40 -0800244 if (!nexthop_nh->nh_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 continue;
David S. Miller71fceff2010-01-15 01:16:40 -0800246 hlist_del(&nexthop_nh->nh_hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 } endfor_nexthops(fi)
248 fi->fib_dead = 1;
249 fib_info_put(fi);
250 }
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700251 spin_unlock_bh(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252}
253
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000254static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255{
256 const struct fib_nh *onh = ofi->fib_nh;
257
258 for_nexthops(fi) {
259 if (nh->nh_oif != onh->nh_oif ||
260 nh->nh_gw != onh->nh_gw ||
261 nh->nh_scope != onh->nh_scope ||
262#ifdef CONFIG_IP_ROUTE_MULTIPATH
263 nh->nh_weight != onh->nh_weight ||
264#endif
Patrick McHardyc7066f72011-01-14 13:36:42 +0100265#ifdef CONFIG_IP_ROUTE_CLASSID
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 nh->nh_tclassid != onh->nh_tclassid ||
267#endif
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000268 ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 return -1;
270 onh++;
271 } endfor_nexthops(fi);
272 return 0;
273}
274
David S. Miller88ebc722008-01-12 21:49:01 -0800275static inline unsigned int fib_devindex_hashfn(unsigned int val)
276{
277 unsigned int mask = DEVINDEX_HASHSIZE - 1;
278
279 return (val ^
280 (val >> DEVINDEX_HASHBITS) ^
281 (val >> (DEVINDEX_HASHBITS * 2))) & mask;
282}
283
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284static inline unsigned int fib_info_hashfn(const struct fib_info *fi)
285{
David S. Miller123b9732011-02-01 15:34:21 -0800286 unsigned int mask = (fib_info_hash_size - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 unsigned int val = fi->fib_nhs;
288
David S. Miller37e826c2011-03-24 18:06:47 -0700289 val ^= (fi->fib_protocol << 8) | fi->fib_scope;
Al Viro81f7bf62006-09-27 18:40:00 -0700290 val ^= (__force u32)fi->fib_prefsrc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 val ^= fi->fib_priority;
David S. Miller88ebc722008-01-12 21:49:01 -0800292 for_nexthops(fi) {
293 val ^= fib_devindex_hashfn(nh->nh_oif);
294 } endfor_nexthops(fi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295
296 return (val ^ (val >> 7) ^ (val >> 12)) & mask;
297}
298
299static struct fib_info *fib_find_info(const struct fib_info *nfi)
300{
301 struct hlist_head *head;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 struct fib_info *fi;
303 unsigned int hash;
304
305 hash = fib_info_hashfn(nfi);
306 head = &fib_info_hash[hash];
307
Sasha Levinb67bfe02013-02-27 17:06:00 -0800308 hlist_for_each_entry(fi, head, fib_hash) {
Octavian Purdila09ad9bc2009-11-25 15:14:13 -0800309 if (!net_eq(fi->fib_net, nfi->fib_net))
Denis V. Lunev4814bdb2008-01-31 18:50:07 -0800310 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 if (fi->fib_nhs != nfi->fib_nhs)
312 continue;
313 if (nfi->fib_protocol == fi->fib_protocol &&
David S. Miller37e826c2011-03-24 18:06:47 -0700314 nfi->fib_scope == fi->fib_scope &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 nfi->fib_prefsrc == fi->fib_prefsrc &&
316 nfi->fib_priority == fi->fib_priority &&
Eric Dumazetf4ef85b2012-10-04 01:25:26 +0000317 nfi->fib_type == fi->fib_type &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 memcmp(nfi->fib_metrics, fi->fib_metrics,
Eric Dumazetfcd13f42011-03-24 07:01:24 +0000319 sizeof(u32) * RTAX_MAX) == 0 &&
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000320 ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0))
322 return fi;
323 }
324
325 return NULL;
326}
327
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328/* Check, that the gateway is already configured.
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000329 * Used only by redirect accept routine.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 */
Al Virod878e72e2006-09-26 22:18:13 -0700331int ip_fib_check_default(__be32 gw, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332{
333 struct hlist_head *head;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 struct fib_nh *nh;
335 unsigned int hash;
336
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700337 spin_lock(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338
339 hash = fib_devindex_hashfn(dev->ifindex);
340 head = &fib_info_devhash[hash];
Sasha Levinb67bfe02013-02-27 17:06:00 -0800341 hlist_for_each_entry(nh, head, nh_hash) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 if (nh->nh_dev == dev &&
343 nh->nh_gw == gw &&
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000344 !(nh->nh_flags & RTNH_F_DEAD)) {
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700345 spin_unlock(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 return 0;
347 }
348 }
349
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700350 spin_unlock(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351
352 return -1;
353}
354
Thomas Graf339bf982006-11-10 14:10:15 -0800355static inline size_t fib_nlmsg_size(struct fib_info *fi)
356{
357 size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
358 + nla_total_size(4) /* RTA_TABLE */
359 + nla_total_size(4) /* RTA_DST */
360 + nla_total_size(4) /* RTA_PRIORITY */
361 + nla_total_size(4); /* RTA_PREFSRC */
362
363 /* space for nested metrics */
364 payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
365
366 if (fi->fib_nhs) {
367 /* Also handles the special case fib_nhs == 1 */
368
369 /* each nexthop is packed in an attribute */
370 size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
371
372 /* may contain flow and gateway attribute */
373 nhsize += 2 * nla_total_size(4);
374
375 /* all nexthops are packed in a nested attribute */
376 payload += nla_total_size(fi->fib_nhs * nhsize);
377 }
378
379 return payload;
380}
381
Al Viro81f7bf62006-09-27 18:40:00 -0700382void rtmsg_fib(int event, __be32 key, struct fib_alias *fa,
Milan Kocianb8f55832007-05-23 14:55:06 -0700383 int dst_len, u32 tb_id, struct nl_info *info,
384 unsigned int nlm_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385{
386 struct sk_buff *skb;
Thomas Graf4e902c52006-08-17 18:14:52 -0700387 u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
Thomas Graff21c7bc2006-08-15 00:34:17 -0700388 int err = -ENOBUFS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389
Thomas Graf339bf982006-11-10 14:10:15 -0800390 skb = nlmsg_new(fib_nlmsg_size(fa->fa_info), GFP_KERNEL);
Thomas Graff21c7bc2006-08-15 00:34:17 -0700391 if (skb == NULL)
392 goto errout;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
Eric W. Biederman15e47302012-09-07 20:12:54 +0000394 err = fib_dump_info(skb, info->portid, seq, event, tb_id,
David S. Miller37e826c2011-03-24 18:06:47 -0700395 fa->fa_type, key, dst_len,
Milan Kocianb8f55832007-05-23 14:55:06 -0700396 fa->fa_tos, fa->fa_info, nlm_flags);
Patrick McHardy26932562007-01-31 23:16:40 -0800397 if (err < 0) {
398 /* -EMSGSIZE implies BUG in fib_nlmsg_size() */
399 WARN_ON(err == -EMSGSIZE);
400 kfree_skb(skb);
401 goto errout;
402 }
Eric W. Biederman15e47302012-09-07 20:12:54 +0000403 rtnl_notify(skb, info->nl_net, info->portid, RTNLGRP_IPV4_ROUTE,
Pablo Neira Ayuso1ce85fe2009-02-24 23:18:28 -0800404 info->nlh, GFP_KERNEL);
405 return;
Thomas Graff21c7bc2006-08-15 00:34:17 -0700406errout:
407 if (err < 0)
Denis V. Lunev4d1169c2008-01-10 03:26:13 -0800408 rtnl_set_sk_err(info->nl_net, RTNLGRP_IPV4_ROUTE, err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409}
410
411/* Return the first fib alias matching TOS with
412 * priority less than or equal to PRIO.
413 */
414struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio)
415{
416 if (fah) {
417 struct fib_alias *fa;
418 list_for_each_entry(fa, fah, fa_list) {
419 if (fa->fa_tos > tos)
420 continue;
421 if (fa->fa_info->fib_priority >= prio ||
422 fa->fa_tos < tos)
423 return fa;
424 }
425 }
426 return NULL;
427}
428
429int fib_detect_death(struct fib_info *fi, int order,
Denis V. Lunevc17860a2007-12-08 00:22:13 -0800430 struct fib_info **last_resort, int *last_idx, int dflt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431{
432 struct neighbour *n;
433 int state = NUD_NONE;
434
435 n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev);
436 if (n) {
437 state = n->nud_state;
438 neigh_release(n);
439 }
Jianjun Kongd93191002008-11-03 00:23:42 -0800440 if (state == NUD_REACHABLE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 return 0;
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000442 if ((state & NUD_VALID) && order != dflt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 return 0;
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000444 if ((state & NUD_VALID) ||
445 (*last_idx < 0 && order > dflt)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 *last_resort = fi;
447 *last_idx = order;
448 }
449 return 1;
450}
451
452#ifdef CONFIG_IP_ROUTE_MULTIPATH
453
Thomas Graf4e902c52006-08-17 18:14:52 -0700454static int fib_count_nexthops(struct rtnexthop *rtnh, int remaining)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455{
456 int nhs = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457
Thomas Graf4e902c52006-08-17 18:14:52 -0700458 while (rtnh_ok(rtnh, remaining)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 nhs++;
Thomas Graf4e902c52006-08-17 18:14:52 -0700460 rtnh = rtnh_next(rtnh, &remaining);
461 }
462
463 /* leftover implies invalid nexthop configuration, discard it */
464 return remaining > 0 ? 0 : nhs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465}
466
Thomas Graf4e902c52006-08-17 18:14:52 -0700467static int fib_get_nhs(struct fib_info *fi, struct rtnexthop *rtnh,
468 int remaining, struct fib_config *cfg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 change_nexthops(fi) {
Thomas Graf4e902c52006-08-17 18:14:52 -0700471 int attrlen;
472
473 if (!rtnh_ok(rtnh, remaining))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 return -EINVAL;
Thomas Graf4e902c52006-08-17 18:14:52 -0700475
David S. Miller71fceff2010-01-15 01:16:40 -0800476 nexthop_nh->nh_flags =
477 (cfg->fc_flags & ~0xFF) | rtnh->rtnh_flags;
478 nexthop_nh->nh_oif = rtnh->rtnh_ifindex;
479 nexthop_nh->nh_weight = rtnh->rtnh_hops + 1;
Thomas Graf4e902c52006-08-17 18:14:52 -0700480
481 attrlen = rtnh_attrlen(rtnh);
482 if (attrlen > 0) {
483 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
484
485 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
David S. Miller71fceff2010-01-15 01:16:40 -0800486 nexthop_nh->nh_gw = nla ? nla_get_be32(nla) : 0;
Patrick McHardyc7066f72011-01-14 13:36:42 +0100487#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Graf4e902c52006-08-17 18:14:52 -0700488 nla = nla_find(attrs, attrlen, RTA_FLOW);
David S. Miller71fceff2010-01-15 01:16:40 -0800489 nexthop_nh->nh_tclassid = nla ? nla_get_u32(nla) : 0;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700490 if (nexthop_nh->nh_tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700491 fi->fib_net->ipv4.fib_num_tclassid_users++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492#endif
493 }
Thomas Graf4e902c52006-08-17 18:14:52 -0700494
495 rtnh = rtnh_next(rtnh, &remaining);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 } endfor_nexthops(fi);
Thomas Graf4e902c52006-08-17 18:14:52 -0700497
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 return 0;
499}
500
501#endif
502
Thomas Graf4e902c52006-08-17 18:14:52 -0700503int fib_nh_match(struct fib_config *cfg, struct fib_info *fi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504{
505#ifdef CONFIG_IP_ROUTE_MULTIPATH
Thomas Graf4e902c52006-08-17 18:14:52 -0700506 struct rtnexthop *rtnh;
507 int remaining;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508#endif
509
Thomas Graf4e902c52006-08-17 18:14:52 -0700510 if (cfg->fc_priority && cfg->fc_priority != fi->fib_priority)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 return 1;
512
Thomas Graf4e902c52006-08-17 18:14:52 -0700513 if (cfg->fc_oif || cfg->fc_gw) {
514 if ((!cfg->fc_oif || cfg->fc_oif == fi->fib_nh->nh_oif) &&
515 (!cfg->fc_gw || cfg->fc_gw == fi->fib_nh->nh_gw))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 return 0;
517 return 1;
518 }
519
520#ifdef CONFIG_IP_ROUTE_MULTIPATH
Thomas Graf4e902c52006-08-17 18:14:52 -0700521 if (cfg->fc_mp == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 return 0;
Thomas Graf4e902c52006-08-17 18:14:52 -0700523
524 rtnh = cfg->fc_mp;
525 remaining = cfg->fc_mp_len;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900526
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 for_nexthops(fi) {
Thomas Graf4e902c52006-08-17 18:14:52 -0700528 int attrlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
Thomas Graf4e902c52006-08-17 18:14:52 -0700530 if (!rtnh_ok(rtnh, remaining))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 return -EINVAL;
Thomas Graf4e902c52006-08-17 18:14:52 -0700532
533 if (rtnh->rtnh_ifindex && rtnh->rtnh_ifindex != nh->nh_oif)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 return 1;
Thomas Graf4e902c52006-08-17 18:14:52 -0700535
536 attrlen = rtnh_attrlen(rtnh);
537 if (attrlen < 0) {
538 struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
539
540 nla = nla_find(attrs, attrlen, RTA_GATEWAY);
Al Viro17fb2c62006-09-26 22:15:25 -0700541 if (nla && nla_get_be32(nla) != nh->nh_gw)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 return 1;
Patrick McHardyc7066f72011-01-14 13:36:42 +0100543#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Graf4e902c52006-08-17 18:14:52 -0700544 nla = nla_find(attrs, attrlen, RTA_FLOW);
545 if (nla && nla_get_u32(nla) != nh->nh_tclassid)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 return 1;
547#endif
548 }
Thomas Graf4e902c52006-08-17 18:14:52 -0700549
550 rtnh = rtnh_next(rtnh, &remaining);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 } endfor_nexthops(fi);
552#endif
553 return 0;
554}
555
556
557/*
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000558 * Picture
559 * -------
560 *
561 * Semantics of nexthop is very messy by historical reasons.
562 * We have to take into account, that:
563 * a) gateway can be actually local interface address,
564 * so that gatewayed route is direct.
565 * b) gateway must be on-link address, possibly
566 * described not by an ifaddr, but also by a direct route.
567 * c) If both gateway and interface are specified, they should not
568 * contradict.
569 * d) If we use tunnel routes, gateway could be not on-link.
570 *
571 * Attempt to reconcile all of these (alas, self-contradictory) conditions
572 * results in pretty ugly and hairy code with obscure logic.
573 *
574 * I chose to generalized it instead, so that the size
575 * of code does not increase practically, but it becomes
576 * much more general.
577 * Every prefix is assigned a "scope" value: "host" is local address,
578 * "link" is direct route,
579 * [ ... "site" ... "interior" ... ]
580 * and "universe" is true gateway route with global meaning.
581 *
582 * Every prefix refers to a set of "nexthop"s (gw, oif),
583 * where gw must have narrower scope. This recursion stops
584 * when gw has LOCAL scope or if "nexthop" is declared ONLINK,
585 * which means that gw is forced to be on link.
586 *
587 * Code is still hairy, but now it is apparently logically
588 * consistent and very flexible. F.e. as by-product it allows
589 * to co-exists in peace independent exterior and interior
590 * routing processes.
591 *
592 * Normally it looks as following.
593 *
594 * {universe prefix} -> (gw, oif) [scope link]
595 * |
596 * |-> {link prefix} -> (gw, oif) [scope local]
597 * |
598 * |-> {local prefix} (terminal node)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 */
Thomas Graf4e902c52006-08-17 18:14:52 -0700600static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
601 struct fib_nh *nh)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602{
603 int err;
Denis V. Lunev86167a32008-01-21 17:34:00 -0800604 struct net *net;
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000605 struct net_device *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606
Denis V. Lunev86167a32008-01-21 17:34:00 -0800607 net = cfg->fc_nlinfo.nl_net;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 if (nh->nh_gw) {
609 struct fib_result res;
610
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000611 if (nh->nh_flags & RTNH_F_ONLINK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612
Thomas Graf4e902c52006-08-17 18:14:52 -0700613 if (cfg->fc_scope >= RT_SCOPE_LINK)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 return -EINVAL;
Denis V. Lunev86167a32008-01-21 17:34:00 -0800615 if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 return -EINVAL;
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000617 dev = __dev_get_by_index(net, nh->nh_oif);
618 if (!dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 return -ENODEV;
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000620 if (!(dev->flags & IFF_UP))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 return -ENETDOWN;
622 nh->nh_dev = dev;
623 dev_hold(dev);
624 nh->nh_scope = RT_SCOPE_LINK;
625 return 0;
626 }
Eric Dumazetebc0ffa2010-10-05 10:41:36 +0000627 rcu_read_lock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 {
David S. Miller9ade2282011-03-12 02:02:42 -0500629 struct flowi4 fl4 = {
630 .daddr = nh->nh_gw,
631 .flowi4_scope = cfg->fc_scope + 1,
632 .flowi4_oif = nh->nh_oif,
Thomas Graf4e902c52006-08-17 18:14:52 -0700633 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634
635 /* It is not necessary, but requires a bit of thinking */
David S. Miller9ade2282011-03-12 02:02:42 -0500636 if (fl4.flowi4_scope < RT_SCOPE_LINK)
637 fl4.flowi4_scope = RT_SCOPE_LINK;
638 err = fib_lookup(net, &fl4, &res);
Eric Dumazetebc0ffa2010-10-05 10:41:36 +0000639 if (err) {
640 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 return err;
Eric Dumazetebc0ffa2010-10-05 10:41:36 +0000642 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 }
644 err = -EINVAL;
645 if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
646 goto out;
647 nh->nh_scope = res.scope;
648 nh->nh_oif = FIB_RES_OIF(res);
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000649 nh->nh_dev = dev = FIB_RES_DEV(res);
650 if (!dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 goto out;
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000652 dev_hold(dev);
Eric Dumazet8723e1b2010-10-19 00:39:26 +0000653 err = (dev->flags & IFF_UP) ? 0 : -ENETDOWN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 } else {
655 struct in_device *in_dev;
656
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000657 if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 return -EINVAL;
659
Eric Dumazet8723e1b2010-10-19 00:39:26 +0000660 rcu_read_lock();
661 err = -ENODEV;
Denis V. Lunev86167a32008-01-21 17:34:00 -0800662 in_dev = inetdev_by_index(net, nh->nh_oif);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 if (in_dev == NULL)
Eric Dumazet8723e1b2010-10-19 00:39:26 +0000664 goto out;
665 err = -ENETDOWN;
666 if (!(in_dev->dev->flags & IFF_UP))
667 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 nh->nh_dev = in_dev->dev;
669 dev_hold(nh->nh_dev);
670 nh->nh_scope = RT_SCOPE_HOST;
Eric Dumazet8723e1b2010-10-19 00:39:26 +0000671 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672 }
Eric Dumazet8723e1b2010-10-19 00:39:26 +0000673out:
674 rcu_read_unlock();
675 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676}
677
Al Viro81f7bf62006-09-27 18:40:00 -0700678static inline unsigned int fib_laddr_hashfn(__be32 val)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679{
David S. Miller123b9732011-02-01 15:34:21 -0800680 unsigned int mask = (fib_info_hash_size - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000682 return ((__force u32)val ^
683 ((__force u32)val >> 7) ^
684 ((__force u32)val >> 14)) & mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685}
686
David S. Miller123b9732011-02-01 15:34:21 -0800687static struct hlist_head *fib_info_hash_alloc(int bytes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688{
689 if (bytes <= PAGE_SIZE)
Joonwoo Park88f83492007-11-26 23:29:32 +0800690 return kzalloc(bytes, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 else
692 return (struct hlist_head *)
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000693 __get_free_pages(GFP_KERNEL | __GFP_ZERO,
694 get_order(bytes));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695}
696
David S. Miller123b9732011-02-01 15:34:21 -0800697static void fib_info_hash_free(struct hlist_head *hash, int bytes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698{
699 if (!hash)
700 return;
701
702 if (bytes <= PAGE_SIZE)
703 kfree(hash);
704 else
705 free_pages((unsigned long) hash, get_order(bytes));
706}
707
David S. Miller123b9732011-02-01 15:34:21 -0800708static void fib_info_hash_move(struct hlist_head *new_info_hash,
709 struct hlist_head *new_laddrhash,
710 unsigned int new_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711{
David S. Millerb7656e72005-08-05 04:12:48 -0700712 struct hlist_head *old_info_hash, *old_laddrhash;
David S. Miller123b9732011-02-01 15:34:21 -0800713 unsigned int old_size = fib_info_hash_size;
David S. Millerb7656e72005-08-05 04:12:48 -0700714 unsigned int i, bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700716 spin_lock_bh(&fib_info_lock);
David S. Millerb7656e72005-08-05 04:12:48 -0700717 old_info_hash = fib_info_hash;
718 old_laddrhash = fib_info_laddrhash;
David S. Miller123b9732011-02-01 15:34:21 -0800719 fib_info_hash_size = new_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720
721 for (i = 0; i < old_size; i++) {
722 struct hlist_head *head = &fib_info_hash[i];
Sasha Levinb67bfe02013-02-27 17:06:00 -0800723 struct hlist_node *n;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 struct fib_info *fi;
725
Sasha Levinb67bfe02013-02-27 17:06:00 -0800726 hlist_for_each_entry_safe(fi, n, head, fib_hash) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 struct hlist_head *dest;
728 unsigned int new_hash;
729
730 hlist_del(&fi->fib_hash);
731
732 new_hash = fib_info_hashfn(fi);
733 dest = &new_info_hash[new_hash];
734 hlist_add_head(&fi->fib_hash, dest);
735 }
736 }
737 fib_info_hash = new_info_hash;
738
739 for (i = 0; i < old_size; i++) {
740 struct hlist_head *lhead = &fib_info_laddrhash[i];
Sasha Levinb67bfe02013-02-27 17:06:00 -0800741 struct hlist_node *n;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 struct fib_info *fi;
743
Sasha Levinb67bfe02013-02-27 17:06:00 -0800744 hlist_for_each_entry_safe(fi, n, lhead, fib_lhash) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 struct hlist_head *ldest;
746 unsigned int new_hash;
747
748 hlist_del(&fi->fib_lhash);
749
750 new_hash = fib_laddr_hashfn(fi->fib_prefsrc);
751 ldest = &new_laddrhash[new_hash];
752 hlist_add_head(&fi->fib_lhash, ldest);
753 }
754 }
755 fib_info_laddrhash = new_laddrhash;
756
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700757 spin_unlock_bh(&fib_info_lock);
David S. Millerb7656e72005-08-05 04:12:48 -0700758
759 bytes = old_size * sizeof(struct hlist_head *);
David S. Miller123b9732011-02-01 15:34:21 -0800760 fib_info_hash_free(old_info_hash, bytes);
761 fib_info_hash_free(old_laddrhash, bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762}
763
David S. Miller436c3b62011-03-24 17:42:21 -0700764__be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh)
765{
766 nh->nh_saddr = inet_select_addr(nh->nh_dev,
767 nh->nh_gw,
David S. Miller37e826c2011-03-24 18:06:47 -0700768 nh->nh_parent->fib_scope);
David S. Miller436c3b62011-03-24 17:42:21 -0700769 nh->nh_saddr_genid = atomic_read(&net->ipv4.dev_addr_genid);
770
771 return nh->nh_saddr;
772}
773
Thomas Graf4e902c52006-08-17 18:14:52 -0700774struct fib_info *fib_create_info(struct fib_config *cfg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775{
776 int err;
777 struct fib_info *fi = NULL;
778 struct fib_info *ofi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 int nhs = 1;
Denis V. Lunev7462bd742008-01-31 18:49:32 -0800780 struct net *net = cfg->fc_nlinfo.nl_net;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
David S. Miller4c8237c2011-03-07 14:27:38 -0800782 if (cfg->fc_type > RTN_MAX)
783 goto err_inval;
784
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 /* Fast check to catch the most weird cases */
Thomas Graf4e902c52006-08-17 18:14:52 -0700786 if (fib_props[cfg->fc_type].scope > cfg->fc_scope)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787 goto err_inval;
788
789#ifdef CONFIG_IP_ROUTE_MULTIPATH
Thomas Graf4e902c52006-08-17 18:14:52 -0700790 if (cfg->fc_mp) {
791 nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 if (nhs == 0)
793 goto err_inval;
794 }
795#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796
797 err = -ENOBUFS;
David S. Miller123b9732011-02-01 15:34:21 -0800798 if (fib_info_cnt >= fib_info_hash_size) {
799 unsigned int new_size = fib_info_hash_size << 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 struct hlist_head *new_info_hash;
801 struct hlist_head *new_laddrhash;
802 unsigned int bytes;
803
804 if (!new_size)
Eric Dumazetd94ce9b2012-10-21 20:12:09 +0000805 new_size = 16;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 bytes = new_size * sizeof(struct hlist_head *);
David S. Miller123b9732011-02-01 15:34:21 -0800807 new_info_hash = fib_info_hash_alloc(bytes);
808 new_laddrhash = fib_info_hash_alloc(bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809 if (!new_info_hash || !new_laddrhash) {
David S. Miller123b9732011-02-01 15:34:21 -0800810 fib_info_hash_free(new_info_hash, bytes);
811 fib_info_hash_free(new_laddrhash, bytes);
Joonwoo Park88f83492007-11-26 23:29:32 +0800812 } else
David S. Miller123b9732011-02-01 15:34:21 -0800813 fib_info_hash_move(new_info_hash, new_laddrhash, new_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814
David S. Miller123b9732011-02-01 15:34:21 -0800815 if (!fib_info_hash_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 goto failure;
817 }
818
Panagiotis Issaris0da974f2006-07-21 14:51:30 -0700819 fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct fib_nh), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 if (fi == NULL)
821 goto failure;
David S. Miller725d1e12011-01-28 14:05:05 -0800822 if (cfg->fc_mx) {
823 fi->fib_metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
824 if (!fi->fib_metrics)
825 goto failure;
826 } else
827 fi->fib_metrics = (u32 *) dst_default_metrics;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 fib_info_cnt++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829
Denis V. Lunev57d7a602008-04-16 02:00:50 -0700830 fi->fib_net = hold_net(net);
Thomas Graf4e902c52006-08-17 18:14:52 -0700831 fi->fib_protocol = cfg->fc_protocol;
David S. Miller37e826c2011-03-24 18:06:47 -0700832 fi->fib_scope = cfg->fc_scope;
Thomas Graf4e902c52006-08-17 18:14:52 -0700833 fi->fib_flags = cfg->fc_flags;
834 fi->fib_priority = cfg->fc_priority;
835 fi->fib_prefsrc = cfg->fc_prefsrc;
Eric Dumazetf4ef85b2012-10-04 01:25:26 +0000836 fi->fib_type = cfg->fc_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837
838 fi->fib_nhs = nhs;
839 change_nexthops(fi) {
David S. Miller71fceff2010-01-15 01:16:40 -0800840 nexthop_nh->nh_parent = fi;
Eric Dumazetd26b3a72012-07-31 05:45:30 +0000841 nexthop_nh->nh_pcpu_rth_output = alloc_percpu(struct rtable __rcu *);
Julian Anastasovf8a17172012-10-08 11:41:17 +0000842 if (!nexthop_nh->nh_pcpu_rth_output)
843 goto failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844 } endfor_nexthops(fi)
845
Thomas Graf4e902c52006-08-17 18:14:52 -0700846 if (cfg->fc_mx) {
847 struct nlattr *nla;
848 int remaining;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849
Thomas Graf4e902c52006-08-17 18:14:52 -0700850 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
Thomas Graf8f4c1f92007-09-12 14:44:36 +0200851 int type = nla_type(nla);
Thomas Graf4e902c52006-08-17 18:14:52 -0700852
853 if (type) {
David S. Miller6fac2622012-06-17 19:47:34 -0700854 u32 val;
855
Thomas Graf4e902c52006-08-17 18:14:52 -0700856 if (type > RTAX_MAX)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 goto err_inval;
David S. Miller6fac2622012-06-17 19:47:34 -0700858 val = nla_get_u32(nla);
859 if (type == RTAX_ADVMSS && val > 65535 - 40)
860 val = 65535 - 40;
David S. Miller710ab6c2012-07-10 07:02:09 -0700861 if (type == RTAX_MTU && val > 65535 - 15)
862 val = 65535 - 15;
David S. Miller6fac2622012-06-17 19:47:34 -0700863 fi->fib_metrics[type - 1] = val;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 }
866 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
Thomas Graf4e902c52006-08-17 18:14:52 -0700868 if (cfg->fc_mp) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869#ifdef CONFIG_IP_ROUTE_MULTIPATH
Thomas Graf4e902c52006-08-17 18:14:52 -0700870 err = fib_get_nhs(fi, cfg->fc_mp, cfg->fc_mp_len, cfg);
871 if (err != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 goto failure;
Thomas Graf4e902c52006-08-17 18:14:52 -0700873 if (cfg->fc_oif && fi->fib_nh->nh_oif != cfg->fc_oif)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 goto err_inval;
Thomas Graf4e902c52006-08-17 18:14:52 -0700875 if (cfg->fc_gw && fi->fib_nh->nh_gw != cfg->fc_gw)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 goto err_inval;
Patrick McHardyc7066f72011-01-14 13:36:42 +0100877#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Graf4e902c52006-08-17 18:14:52 -0700878 if (cfg->fc_flow && fi->fib_nh->nh_tclassid != cfg->fc_flow)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 goto err_inval;
880#endif
881#else
882 goto err_inval;
883#endif
884 } else {
885 struct fib_nh *nh = fi->fib_nh;
Thomas Graf4e902c52006-08-17 18:14:52 -0700886
887 nh->nh_oif = cfg->fc_oif;
888 nh->nh_gw = cfg->fc_gw;
889 nh->nh_flags = cfg->fc_flags;
Patrick McHardyc7066f72011-01-14 13:36:42 +0100890#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Graf4e902c52006-08-17 18:14:52 -0700891 nh->nh_tclassid = cfg->fc_flow;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700892 if (nh->nh_tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700893 fi->fib_net->ipv4.fib_num_tclassid_users++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895#ifdef CONFIG_IP_ROUTE_MULTIPATH
896 nh->nh_weight = 1;
897#endif
898 }
899
Thomas Graf4e902c52006-08-17 18:14:52 -0700900 if (fib_props[cfg->fc_type].error) {
901 if (cfg->fc_gw || cfg->fc_oif || cfg->fc_mp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902 goto err_inval;
903 goto link_it;
David S. Miller4c8237c2011-03-07 14:27:38 -0800904 } else {
905 switch (cfg->fc_type) {
906 case RTN_UNICAST:
907 case RTN_LOCAL:
908 case RTN_BROADCAST:
909 case RTN_ANYCAST:
910 case RTN_MULTICAST:
911 break;
912 default:
913 goto err_inval;
914 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 }
916
Thomas Graf4e902c52006-08-17 18:14:52 -0700917 if (cfg->fc_scope > RT_SCOPE_HOST)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 goto err_inval;
919
Thomas Graf4e902c52006-08-17 18:14:52 -0700920 if (cfg->fc_scope == RT_SCOPE_HOST) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 struct fib_nh *nh = fi->fib_nh;
922
923 /* Local address is added. */
924 if (nhs != 1 || nh->nh_gw)
925 goto err_inval;
926 nh->nh_scope = RT_SCOPE_NOWHERE;
Denis V. Lunev7462bd742008-01-31 18:49:32 -0800927 nh->nh_dev = dev_get_by_index(net, fi->fib_nh->nh_oif);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928 err = -ENODEV;
929 if (nh->nh_dev == NULL)
930 goto failure;
931 } else {
932 change_nexthops(fi) {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000933 err = fib_check_nh(cfg, fi, nexthop_nh);
934 if (err != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935 goto failure;
936 } endfor_nexthops(fi)
937 }
938
939 if (fi->fib_prefsrc) {
Thomas Graf4e902c52006-08-17 18:14:52 -0700940 if (cfg->fc_type != RTN_LOCAL || !cfg->fc_dst ||
941 fi->fib_prefsrc != cfg->fc_dst)
Denis V. Lunev7462bd742008-01-31 18:49:32 -0800942 if (inet_addr_type(net, fi->fib_prefsrc) != RTN_LOCAL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 goto err_inval;
944 }
945
David S. Miller1fc050a2011-03-07 20:54:48 -0800946 change_nexthops(fi) {
David S. Miller436c3b62011-03-24 17:42:21 -0700947 fib_info_update_nh_saddr(net, nexthop_nh);
David S. Miller1fc050a2011-03-07 20:54:48 -0800948 } endfor_nexthops(fi)
949
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950link_it:
Eric Dumazet6a31d2a2010-10-04 20:00:18 +0000951 ofi = fib_find_info(fi);
952 if (ofi) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 fi->fib_dead = 1;
954 free_fib_info(fi);
955 ofi->fib_treeref++;
956 return ofi;
957 }
958
959 fi->fib_treeref++;
960 atomic_inc(&fi->fib_clntref);
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700961 spin_lock_bh(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962 hlist_add_head(&fi->fib_hash,
963 &fib_info_hash[fib_info_hashfn(fi)]);
964 if (fi->fib_prefsrc) {
965 struct hlist_head *head;
966
967 head = &fib_info_laddrhash[fib_laddr_hashfn(fi->fib_prefsrc)];
968 hlist_add_head(&fi->fib_lhash, head);
969 }
970 change_nexthops(fi) {
971 struct hlist_head *head;
972 unsigned int hash;
973
David S. Miller71fceff2010-01-15 01:16:40 -0800974 if (!nexthop_nh->nh_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 continue;
David S. Miller71fceff2010-01-15 01:16:40 -0800976 hash = fib_devindex_hashfn(nexthop_nh->nh_dev->ifindex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977 head = &fib_info_devhash[hash];
David S. Miller71fceff2010-01-15 01:16:40 -0800978 hlist_add_head(&nexthop_nh->nh_hash, head);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 } endfor_nexthops(fi)
Stephen Hemminger832b4c52006-08-29 16:48:09 -0700980 spin_unlock_bh(&fib_info_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 return fi;
982
983err_inval:
984 err = -EINVAL;
985
986failure:
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900987 if (fi) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988 fi->fib_dead = 1;
989 free_fib_info(fi);
990 }
Thomas Graf4e902c52006-08-17 18:14:52 -0700991
992 return ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993}
994
Eric W. Biederman15e47302012-09-07 20:12:54 +0000995int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
David S. Miller37e826c2011-03-24 18:06:47 -0700996 u32 tb_id, u8 type, __be32 dst, int dst_len, u8 tos,
Thomas Grafbe403ea2006-08-17 18:15:17 -0700997 struct fib_info *fi, unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998{
Thomas Grafbe403ea2006-08-17 18:15:17 -0700999 struct nlmsghdr *nlh;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000 struct rtmsg *rtm;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001
Eric W. Biederman15e47302012-09-07 20:12:54 +00001002 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
Thomas Grafbe403ea2006-08-17 18:15:17 -07001003 if (nlh == NULL)
Patrick McHardy26932562007-01-31 23:16:40 -08001004 return -EMSGSIZE;
Thomas Grafbe403ea2006-08-17 18:15:17 -07001005
1006 rtm = nlmsg_data(nlh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 rtm->rtm_family = AF_INET;
1008 rtm->rtm_dst_len = dst_len;
1009 rtm->rtm_src_len = 0;
1010 rtm->rtm_tos = tos;
Krzysztof Piotr Oledzki709772e2008-06-10 15:44:49 -07001011 if (tb_id < 256)
1012 rtm->rtm_table = tb_id;
1013 else
1014 rtm->rtm_table = RT_TABLE_COMPAT;
David S. Millerf3756b72012-04-01 20:39:02 -04001015 if (nla_put_u32(skb, RTA_TABLE, tb_id))
1016 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017 rtm->rtm_type = type;
1018 rtm->rtm_flags = fi->fib_flags;
David S. Miller37e826c2011-03-24 18:06:47 -07001019 rtm->rtm_scope = fi->fib_scope;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020 rtm->rtm_protocol = fi->fib_protocol;
Thomas Grafbe403ea2006-08-17 18:15:17 -07001021
David S. Millerf3756b72012-04-01 20:39:02 -04001022 if (rtm->rtm_dst_len &&
1023 nla_put_be32(skb, RTA_DST, dst))
1024 goto nla_put_failure;
1025 if (fi->fib_priority &&
1026 nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority))
1027 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028 if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
Thomas Grafbe403ea2006-08-17 18:15:17 -07001029 goto nla_put_failure;
1030
David S. Millerf3756b72012-04-01 20:39:02 -04001031 if (fi->fib_prefsrc &&
1032 nla_put_be32(skb, RTA_PREFSRC, fi->fib_prefsrc))
1033 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034 if (fi->fib_nhs == 1) {
David S. Millerf3756b72012-04-01 20:39:02 -04001035 if (fi->fib_nh->nh_gw &&
1036 nla_put_be32(skb, RTA_GATEWAY, fi->fib_nh->nh_gw))
1037 goto nla_put_failure;
1038 if (fi->fib_nh->nh_oif &&
1039 nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif))
1040 goto nla_put_failure;
Patrick McHardyc7066f72011-01-14 13:36:42 +01001041#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Millerf3756b72012-04-01 20:39:02 -04001042 if (fi->fib_nh[0].nh_tclassid &&
1043 nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid))
1044 goto nla_put_failure;
Patrick McHardy8265abc2006-07-21 15:09:55 -07001045#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046 }
1047#ifdef CONFIG_IP_ROUTE_MULTIPATH
1048 if (fi->fib_nhs > 1) {
Thomas Grafbe403ea2006-08-17 18:15:17 -07001049 struct rtnexthop *rtnh;
1050 struct nlattr *mp;
1051
1052 mp = nla_nest_start(skb, RTA_MULTIPATH);
1053 if (mp == NULL)
1054 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055
1056 for_nexthops(fi) {
Thomas Grafbe403ea2006-08-17 18:15:17 -07001057 rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh));
1058 if (rtnh == NULL)
1059 goto nla_put_failure;
1060
1061 rtnh->rtnh_flags = nh->nh_flags & 0xFF;
1062 rtnh->rtnh_hops = nh->nh_weight - 1;
1063 rtnh->rtnh_ifindex = nh->nh_oif;
1064
David S. Millerf3756b72012-04-01 20:39:02 -04001065 if (nh->nh_gw &&
1066 nla_put_be32(skb, RTA_GATEWAY, nh->nh_gw))
1067 goto nla_put_failure;
Patrick McHardyc7066f72011-01-14 13:36:42 +01001068#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Millerf3756b72012-04-01 20:39:02 -04001069 if (nh->nh_tclassid &&
1070 nla_put_u32(skb, RTA_FLOW, nh->nh_tclassid))
1071 goto nla_put_failure;
Patrick McHardy8265abc2006-07-21 15:09:55 -07001072#endif
Thomas Grafbe403ea2006-08-17 18:15:17 -07001073 /* length of rtnetlink header + attributes */
1074 rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *) rtnh;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 } endfor_nexthops(fi);
Thomas Grafbe403ea2006-08-17 18:15:17 -07001076
1077 nla_nest_end(skb, mp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 }
1079#endif
Thomas Grafbe403ea2006-08-17 18:15:17 -07001080 return nlmsg_end(skb, nlh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081
Thomas Grafbe403ea2006-08-17 18:15:17 -07001082nla_put_failure:
Patrick McHardy26932562007-01-31 23:16:40 -08001083 nlmsg_cancel(skb, nlh);
1084 return -EMSGSIZE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085}
1086
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087/*
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001088 * Update FIB if:
1089 * - local address disappeared -> we must delete all the entries
1090 * referring to it.
1091 * - device went down -> we must shutdown all nexthops going via it.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 */
Denis V. Lunev4814bdb2008-01-31 18:50:07 -08001093int fib_sync_down_addr(struct net *net, __be32 local)
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001094{
1095 int ret = 0;
1096 unsigned int hash = fib_laddr_hashfn(local);
1097 struct hlist_head *head = &fib_info_laddrhash[hash];
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001098 struct fib_info *fi;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001100 if (fib_info_laddrhash == NULL || local == 0)
1101 return 0;
1102
Sasha Levinb67bfe02013-02-27 17:06:00 -08001103 hlist_for_each_entry(fi, head, fib_lhash) {
Octavian Purdila09ad9bc2009-11-25 15:14:13 -08001104 if (!net_eq(fi->fib_net, net))
Denis V. Lunev4814bdb2008-01-31 18:50:07 -08001105 continue;
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001106 if (fi->fib_prefsrc == local) {
1107 fi->fib_flags |= RTNH_F_DEAD;
1108 ret++;
1109 }
1110 }
1111 return ret;
1112}
1113
1114int fib_sync_down_dev(struct net_device *dev, int force)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115{
1116 int ret = 0;
1117 int scope = RT_SCOPE_NOWHERE;
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001118 struct fib_info *prev_fi = NULL;
1119 unsigned int hash = fib_devindex_hashfn(dev->ifindex);
1120 struct hlist_head *head = &fib_info_devhash[hash];
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001121 struct fib_nh *nh;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001122
Linus Torvalds1da177e2005-04-16 15:20:36 -07001123 if (force)
1124 scope = -1;
1125
Sasha Levinb67bfe02013-02-27 17:06:00 -08001126 hlist_for_each_entry(nh, head, nh_hash) {
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001127 struct fib_info *fi = nh->nh_parent;
1128 int dead;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001130 BUG_ON(!fi->fib_nhs);
1131 if (nh->nh_dev != dev || fi == prev_fi)
1132 continue;
1133 prev_fi = fi;
1134 dead = 0;
1135 change_nexthops(fi) {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001136 if (nexthop_nh->nh_flags & RTNH_F_DEAD)
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001137 dead++;
David S. Miller71fceff2010-01-15 01:16:40 -08001138 else if (nexthop_nh->nh_dev == dev &&
1139 nexthop_nh->nh_scope != scope) {
1140 nexthop_nh->nh_flags |= RTNH_F_DEAD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141#ifdef CONFIG_IP_ROUTE_MULTIPATH
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001142 spin_lock_bh(&fib_multipath_lock);
David S. Miller71fceff2010-01-15 01:16:40 -08001143 fi->fib_power -= nexthop_nh->nh_power;
1144 nexthop_nh->nh_power = 0;
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001145 spin_unlock_bh(&fib_multipath_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001146#endif
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001147 dead++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148 }
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001149#ifdef CONFIG_IP_ROUTE_MULTIPATH
David S. Miller71fceff2010-01-15 01:16:40 -08001150 if (force > 1 && nexthop_nh->nh_dev == dev) {
Denis V. Lunev85326fa2008-01-31 18:48:47 -08001151 dead = fi->fib_nhs;
1152 break;
1153 }
1154#endif
1155 } endfor_nexthops(fi)
1156 if (dead == fi->fib_nhs) {
1157 fi->fib_flags |= RTNH_F_DEAD;
1158 ret++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001159 }
1160 }
1161
1162 return ret;
1163}
1164
David S. Miller0c838ff2011-01-31 16:16:50 -08001165/* Must be invoked inside of an RCU protected region. */
1166void fib_select_default(struct fib_result *res)
1167{
1168 struct fib_info *fi = NULL, *last_resort = NULL;
1169 struct list_head *fa_head = res->fa_head;
1170 struct fib_table *tb = res->table;
1171 int order = -1, last_idx = -1;
1172 struct fib_alias *fa;
1173
1174 list_for_each_entry_rcu(fa, fa_head, fa_list) {
1175 struct fib_info *next_fi = fa->fa_info;
1176
David S. Miller37e826c2011-03-24 18:06:47 -07001177 if (next_fi->fib_scope != res->scope ||
David S. Miller0c838ff2011-01-31 16:16:50 -08001178 fa->fa_type != RTN_UNICAST)
1179 continue;
1180
1181 if (next_fi->fib_priority > res->fi->fib_priority)
1182 break;
1183 if (!next_fi->fib_nh[0].nh_gw ||
1184 next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
1185 continue;
1186
1187 fib_alias_accessed(fa);
1188
1189 if (fi == NULL) {
1190 if (next_fi != res->fi)
1191 break;
1192 } else if (!fib_detect_death(fi, order, &last_resort,
1193 &last_idx, tb->tb_default)) {
1194 fib_result_assign(res, fi);
1195 tb->tb_default = order;
1196 goto out;
1197 }
1198 fi = next_fi;
1199 order++;
1200 }
1201
1202 if (order <= 0 || fi == NULL) {
1203 tb->tb_default = -1;
1204 goto out;
1205 }
1206
1207 if (!fib_detect_death(fi, order, &last_resort, &last_idx,
1208 tb->tb_default)) {
1209 fib_result_assign(res, fi);
1210 tb->tb_default = order;
1211 goto out;
1212 }
1213
1214 if (last_idx >= 0)
1215 fib_result_assign(res, last_resort);
1216 tb->tb_default = last_idx;
1217out:
Eric Dumazet31d40932011-02-14 11:23:04 -08001218 return;
David S. Miller0c838ff2011-01-31 16:16:50 -08001219}
1220
Linus Torvalds1da177e2005-04-16 15:20:36 -07001221#ifdef CONFIG_IP_ROUTE_MULTIPATH
1222
1223/*
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001224 * Dead device goes up. We wake up dead nexthops.
1225 * It takes sense only on multipath routes.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227int fib_sync_up(struct net_device *dev)
1228{
1229 struct fib_info *prev_fi;
1230 unsigned int hash;
1231 struct hlist_head *head;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232 struct fib_nh *nh;
1233 int ret;
1234
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001235 if (!(dev->flags & IFF_UP))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236 return 0;
1237
1238 prev_fi = NULL;
1239 hash = fib_devindex_hashfn(dev->ifindex);
1240 head = &fib_info_devhash[hash];
1241 ret = 0;
1242
Sasha Levinb67bfe02013-02-27 17:06:00 -08001243 hlist_for_each_entry(nh, head, nh_hash) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001244 struct fib_info *fi = nh->nh_parent;
1245 int alive;
1246
1247 BUG_ON(!fi->fib_nhs);
1248 if (nh->nh_dev != dev || fi == prev_fi)
1249 continue;
1250
1251 prev_fi = fi;
1252 alive = 0;
1253 change_nexthops(fi) {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001254 if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255 alive++;
1256 continue;
1257 }
David S. Miller71fceff2010-01-15 01:16:40 -08001258 if (nexthop_nh->nh_dev == NULL ||
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001259 !(nexthop_nh->nh_dev->flags & IFF_UP))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260 continue;
David S. Miller71fceff2010-01-15 01:16:40 -08001261 if (nexthop_nh->nh_dev != dev ||
1262 !__in_dev_get_rtnl(dev))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263 continue;
1264 alive++;
1265 spin_lock_bh(&fib_multipath_lock);
David S. Miller71fceff2010-01-15 01:16:40 -08001266 nexthop_nh->nh_power = 0;
1267 nexthop_nh->nh_flags &= ~RTNH_F_DEAD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268 spin_unlock_bh(&fib_multipath_lock);
1269 } endfor_nexthops(fi)
1270
1271 if (alive > 0) {
1272 fi->fib_flags &= ~RTNH_F_DEAD;
1273 ret++;
1274 }
1275 }
1276
1277 return ret;
1278}
1279
1280/*
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001281 * The algorithm is suboptimal, but it provides really
1282 * fair weighted route distribution.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283 */
David S. Miller1b7fe5932011-03-10 17:01:16 -08001284void fib_select_multipath(struct fib_result *res)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285{
1286 struct fib_info *fi = res->fi;
1287 int w;
1288
1289 spin_lock_bh(&fib_multipath_lock);
1290 if (fi->fib_power <= 0) {
1291 int power = 0;
1292 change_nexthops(fi) {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001293 if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) {
David S. Miller71fceff2010-01-15 01:16:40 -08001294 power += nexthop_nh->nh_weight;
1295 nexthop_nh->nh_power = nexthop_nh->nh_weight;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 }
1297 } endfor_nexthops(fi);
1298 fi->fib_power = power;
1299 if (power <= 0) {
1300 spin_unlock_bh(&fib_multipath_lock);
1301 /* Race condition: route has just become dead. */
1302 res->nh_sel = 0;
1303 return;
1304 }
1305 }
1306
1307
1308 /* w should be random number [0..fi->fib_power-1],
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001309 * it is pretty bad approximation.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001310 */
1311
1312 w = jiffies % fi->fib_power;
1313
1314 change_nexthops(fi) {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001315 if (!(nexthop_nh->nh_flags & RTNH_F_DEAD) &&
David S. Miller71fceff2010-01-15 01:16:40 -08001316 nexthop_nh->nh_power) {
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00001317 w -= nexthop_nh->nh_power;
1318 if (w <= 0) {
David S. Miller71fceff2010-01-15 01:16:40 -08001319 nexthop_nh->nh_power--;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320 fi->fib_power--;
1321 res->nh_sel = nhsel;
1322 spin_unlock_bh(&fib_multipath_lock);
1323 return;
1324 }
1325 }
1326 } endfor_nexthops(fi);
1327
1328 /* Race condition: route has just become dead. */
1329 res->nh_sel = 0;
1330 spin_unlock_bh(&fib_multipath_lock);
1331}
1332#endif