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Commit | Line | Data |
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1da177e4 LT |
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 | * ROUTE - implementation of the IP router. | |
7 | * | |
02c30a84 | 8 | * Authors: Ross Biro |
1da177e4 LT |
9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
10 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
11 | * Linus Torvalds, <Linus.Torvalds@helsinki.fi> | |
12 | * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
13 | * | |
14 | * Fixes: | |
15 | * Alan Cox : Verify area fixes. | |
16 | * Alan Cox : cli() protects routing changes | |
17 | * Rui Oliveira : ICMP routing table updates | |
18 | * (rco@di.uminho.pt) Routing table insertion and update | |
19 | * Linus Torvalds : Rewrote bits to be sensible | |
20 | * Alan Cox : Added BSD route gw semantics | |
e905a9ed | 21 | * Alan Cox : Super /proc >4K |
1da177e4 LT |
22 | * Alan Cox : MTU in route table |
23 | * Alan Cox : MSS actually. Also added the window | |
24 | * clamper. | |
25 | * Sam Lantinga : Fixed route matching in rt_del() | |
26 | * Alan Cox : Routing cache support. | |
27 | * Alan Cox : Removed compatibility cruft. | |
28 | * Alan Cox : RTF_REJECT support. | |
29 | * Alan Cox : TCP irtt support. | |
30 | * Jonathan Naylor : Added Metric support. | |
31 | * Miquel van Smoorenburg : BSD API fixes. | |
32 | * Miquel van Smoorenburg : Metrics. | |
33 | * Alan Cox : Use __u32 properly | |
34 | * Alan Cox : Aligned routing errors more closely with BSD | |
35 | * our system is still very different. | |
36 | * Alan Cox : Faster /proc handling | |
37 | * Alexey Kuznetsov : Massive rework to support tree based routing, | |
38 | * routing caches and better behaviour. | |
e905a9ed | 39 | * |
1da177e4 LT |
40 | * Olaf Erb : irtt wasn't being copied right. |
41 | * Bjorn Ekwall : Kerneld route support. | |
42 | * Alan Cox : Multicast fixed (I hope) | |
43 | * Pavel Krauz : Limited broadcast fixed | |
44 | * Mike McLagan : Routing by source | |
45 | * Alexey Kuznetsov : End of old history. Split to fib.c and | |
46 | * route.c and rewritten from scratch. | |
47 | * Andi Kleen : Load-limit warning messages. | |
48 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. | |
49 | * Vitaly E. Lavrov : Race condition in ip_route_input_slow. | |
50 | * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow. | |
51 | * Vladimir V. Ivanov : IP rule info (flowid) is really useful. | |
52 | * Marc Boucher : routing by fwmark | |
53 | * Robert Olsson : Added rt_cache statistics | |
54 | * Arnaldo C. Melo : Convert proc stuff to seq_file | |
bb1d23b0 | 55 | * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes. |
cef2685e IS |
56 | * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect |
57 | * Ilia Sotnikov : Removed TOS from hash calculations | |
1da177e4 LT |
58 | * |
59 | * This program is free software; you can redistribute it and/or | |
60 | * modify it under the terms of the GNU General Public License | |
61 | * as published by the Free Software Foundation; either version | |
62 | * 2 of the License, or (at your option) any later version. | |
63 | */ | |
64 | ||
1da177e4 LT |
65 | #include <linux/module.h> |
66 | #include <asm/uaccess.h> | |
67 | #include <asm/system.h> | |
68 | #include <linux/bitops.h> | |
69 | #include <linux/types.h> | |
70 | #include <linux/kernel.h> | |
1da177e4 | 71 | #include <linux/mm.h> |
424c4b70 | 72 | #include <linux/bootmem.h> |
1da177e4 LT |
73 | #include <linux/string.h> |
74 | #include <linux/socket.h> | |
75 | #include <linux/sockios.h> | |
76 | #include <linux/errno.h> | |
77 | #include <linux/in.h> | |
78 | #include <linux/inet.h> | |
79 | #include <linux/netdevice.h> | |
80 | #include <linux/proc_fs.h> | |
81 | #include <linux/init.h> | |
39c90ece | 82 | #include <linux/workqueue.h> |
1da177e4 | 83 | #include <linux/skbuff.h> |
1da177e4 LT |
84 | #include <linux/inetdevice.h> |
85 | #include <linux/igmp.h> | |
86 | #include <linux/pkt_sched.h> | |
87 | #include <linux/mroute.h> | |
88 | #include <linux/netfilter_ipv4.h> | |
89 | #include <linux/random.h> | |
90 | #include <linux/jhash.h> | |
91 | #include <linux/rcupdate.h> | |
92 | #include <linux/times.h> | |
5a0e3ad6 | 93 | #include <linux/slab.h> |
b9eda06f | 94 | #include <linux/prefetch.h> |
352e512c | 95 | #include <net/dst.h> |
457c4cbc | 96 | #include <net/net_namespace.h> |
1da177e4 LT |
97 | #include <net/protocol.h> |
98 | #include <net/ip.h> | |
99 | #include <net/route.h> | |
100 | #include <net/inetpeer.h> | |
101 | #include <net/sock.h> | |
102 | #include <net/ip_fib.h> | |
103 | #include <net/arp.h> | |
104 | #include <net/tcp.h> | |
105 | #include <net/icmp.h> | |
106 | #include <net/xfrm.h> | |
8d71740c | 107 | #include <net/netevent.h> |
63f3444f | 108 | #include <net/rtnetlink.h> |
1da177e4 LT |
109 | #ifdef CONFIG_SYSCTL |
110 | #include <linux/sysctl.h> | |
111 | #endif | |
6e5714ea | 112 | #include <net/secure_seq.h> |
1da177e4 | 113 | |
68a5e3dd | 114 | #define RT_FL_TOS(oldflp4) \ |
f61759e6 | 115 | ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) |
1da177e4 LT |
116 | |
117 | #define IP_MAX_MTU 0xFFF0 | |
118 | ||
119 | #define RT_GC_TIMEOUT (300*HZ) | |
120 | ||
1da177e4 | 121 | static int ip_rt_max_size; |
817bc4db | 122 | static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; |
9f28a2fc | 123 | static int ip_rt_gc_interval __read_mostly = 60 * HZ; |
817bc4db SH |
124 | static int ip_rt_gc_min_interval __read_mostly = HZ / 2; |
125 | static int ip_rt_redirect_number __read_mostly = 9; | |
126 | static int ip_rt_redirect_load __read_mostly = HZ / 50; | |
127 | static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); | |
128 | static int ip_rt_error_cost __read_mostly = HZ; | |
129 | static int ip_rt_error_burst __read_mostly = 5 * HZ; | |
130 | static int ip_rt_gc_elasticity __read_mostly = 8; | |
131 | static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; | |
132 | static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; | |
133 | static int ip_rt_min_advmss __read_mostly = 256; | |
1080d709 | 134 | static int rt_chain_length_max __read_mostly = 20; |
1da177e4 | 135 | |
9f28a2fc ED |
136 | static struct delayed_work expires_work; |
137 | static unsigned long expires_ljiffies; | |
138 | ||
1da177e4 LT |
139 | /* |
140 | * Interface to generic destination cache. | |
141 | */ | |
142 | ||
143 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
0dbaee3b | 144 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst); |
ebb762f2 | 145 | static unsigned int ipv4_mtu(const struct dst_entry *dst); |
1da177e4 | 146 | static void ipv4_dst_destroy(struct dst_entry *dst); |
1da177e4 LT |
147 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); |
148 | static void ipv4_link_failure(struct sk_buff *skb); | |
149 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu); | |
569d3645 | 150 | static int rt_garbage_collect(struct dst_ops *ops); |
1da177e4 | 151 | |
72cdd1d9 ED |
152 | static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, |
153 | int how) | |
154 | { | |
155 | } | |
1da177e4 | 156 | |
62fa8a84 DM |
157 | static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) |
158 | { | |
06582540 DM |
159 | struct rtable *rt = (struct rtable *) dst; |
160 | struct inet_peer *peer; | |
161 | u32 *p = NULL; | |
162 | ||
163 | if (!rt->peer) | |
a48eff12 | 164 | rt_bind_peer(rt, rt->rt_dst, 1); |
62fa8a84 | 165 | |
06582540 DM |
166 | peer = rt->peer; |
167 | if (peer) { | |
62fa8a84 DM |
168 | u32 *old_p = __DST_METRICS_PTR(old); |
169 | unsigned long prev, new; | |
170 | ||
06582540 DM |
171 | p = peer->metrics; |
172 | if (inet_metrics_new(peer)) | |
173 | memcpy(p, old_p, sizeof(u32) * RTAX_MAX); | |
62fa8a84 DM |
174 | |
175 | new = (unsigned long) p; | |
176 | prev = cmpxchg(&dst->_metrics, old, new); | |
177 | ||
178 | if (prev != old) { | |
62fa8a84 DM |
179 | p = __DST_METRICS_PTR(prev); |
180 | if (prev & DST_METRICS_READ_ONLY) | |
181 | p = NULL; | |
182 | } else { | |
62fa8a84 DM |
183 | if (rt->fi) { |
184 | fib_info_put(rt->fi); | |
185 | rt->fi = NULL; | |
186 | } | |
187 | } | |
188 | } | |
189 | return p; | |
190 | } | |
191 | ||
d3aaeb38 DM |
192 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr); |
193 | ||
1da177e4 LT |
194 | static struct dst_ops ipv4_dst_ops = { |
195 | .family = AF_INET, | |
09640e63 | 196 | .protocol = cpu_to_be16(ETH_P_IP), |
1da177e4 LT |
197 | .gc = rt_garbage_collect, |
198 | .check = ipv4_dst_check, | |
0dbaee3b | 199 | .default_advmss = ipv4_default_advmss, |
ebb762f2 | 200 | .mtu = ipv4_mtu, |
62fa8a84 | 201 | .cow_metrics = ipv4_cow_metrics, |
1da177e4 LT |
202 | .destroy = ipv4_dst_destroy, |
203 | .ifdown = ipv4_dst_ifdown, | |
204 | .negative_advice = ipv4_negative_advice, | |
205 | .link_failure = ipv4_link_failure, | |
206 | .update_pmtu = ip_rt_update_pmtu, | |
1ac06e03 | 207 | .local_out = __ip_local_out, |
d3aaeb38 | 208 | .neigh_lookup = ipv4_neigh_lookup, |
1da177e4 LT |
209 | }; |
210 | ||
211 | #define ECN_OR_COST(class) TC_PRIO_##class | |
212 | ||
4839c52b | 213 | const __u8 ip_tos2prio[16] = { |
1da177e4 | 214 | TC_PRIO_BESTEFFORT, |
4a2b9c37 | 215 | ECN_OR_COST(BESTEFFORT), |
1da177e4 LT |
216 | TC_PRIO_BESTEFFORT, |
217 | ECN_OR_COST(BESTEFFORT), | |
218 | TC_PRIO_BULK, | |
219 | ECN_OR_COST(BULK), | |
220 | TC_PRIO_BULK, | |
221 | ECN_OR_COST(BULK), | |
222 | TC_PRIO_INTERACTIVE, | |
223 | ECN_OR_COST(INTERACTIVE), | |
224 | TC_PRIO_INTERACTIVE, | |
225 | ECN_OR_COST(INTERACTIVE), | |
226 | TC_PRIO_INTERACTIVE_BULK, | |
227 | ECN_OR_COST(INTERACTIVE_BULK), | |
228 | TC_PRIO_INTERACTIVE_BULK, | |
229 | ECN_OR_COST(INTERACTIVE_BULK) | |
230 | }; | |
231 | ||
232 | ||
233 | /* | |
234 | * Route cache. | |
235 | */ | |
236 | ||
237 | /* The locking scheme is rather straight forward: | |
238 | * | |
239 | * 1) Read-Copy Update protects the buckets of the central route hash. | |
240 | * 2) Only writers remove entries, and they hold the lock | |
241 | * as they look at rtable reference counts. | |
242 | * 3) Only readers acquire references to rtable entries, | |
243 | * they do so with atomic increments and with the | |
244 | * lock held. | |
245 | */ | |
246 | ||
247 | struct rt_hash_bucket { | |
1c31720a | 248 | struct rtable __rcu *chain; |
22c047cc | 249 | }; |
1080d709 | 250 | |
8a25d5de IM |
251 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ |
252 | defined(CONFIG_PROVE_LOCKING) | |
22c047cc ED |
253 | /* |
254 | * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks | |
255 | * The size of this table is a power of two and depends on the number of CPUS. | |
62051200 | 256 | * (on lockdep we have a quite big spinlock_t, so keep the size down there) |
22c047cc | 257 | */ |
62051200 IM |
258 | #ifdef CONFIG_LOCKDEP |
259 | # define RT_HASH_LOCK_SZ 256 | |
22c047cc | 260 | #else |
62051200 IM |
261 | # if NR_CPUS >= 32 |
262 | # define RT_HASH_LOCK_SZ 4096 | |
263 | # elif NR_CPUS >= 16 | |
264 | # define RT_HASH_LOCK_SZ 2048 | |
265 | # elif NR_CPUS >= 8 | |
266 | # define RT_HASH_LOCK_SZ 1024 | |
267 | # elif NR_CPUS >= 4 | |
268 | # define RT_HASH_LOCK_SZ 512 | |
269 | # else | |
270 | # define RT_HASH_LOCK_SZ 256 | |
271 | # endif | |
22c047cc ED |
272 | #endif |
273 | ||
274 | static spinlock_t *rt_hash_locks; | |
275 | # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)] | |
1ff1cc20 PE |
276 | |
277 | static __init void rt_hash_lock_init(void) | |
278 | { | |
279 | int i; | |
280 | ||
281 | rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ, | |
282 | GFP_KERNEL); | |
283 | if (!rt_hash_locks) | |
284 | panic("IP: failed to allocate rt_hash_locks\n"); | |
285 | ||
286 | for (i = 0; i < RT_HASH_LOCK_SZ; i++) | |
287 | spin_lock_init(&rt_hash_locks[i]); | |
288 | } | |
22c047cc ED |
289 | #else |
290 | # define rt_hash_lock_addr(slot) NULL | |
1ff1cc20 PE |
291 | |
292 | static inline void rt_hash_lock_init(void) | |
293 | { | |
294 | } | |
22c047cc | 295 | #endif |
1da177e4 | 296 | |
817bc4db SH |
297 | static struct rt_hash_bucket *rt_hash_table __read_mostly; |
298 | static unsigned rt_hash_mask __read_mostly; | |
299 | static unsigned int rt_hash_log __read_mostly; | |
1da177e4 | 300 | |
2f970d83 | 301 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); |
27f39c73 | 302 | #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field) |
1da177e4 | 303 | |
b00180de | 304 | static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx, |
0eae88f3 | 305 | int genid) |
1da177e4 | 306 | { |
0eae88f3 | 307 | return jhash_3words((__force u32)daddr, (__force u32)saddr, |
b00180de | 308 | idx, genid) |
29e75252 | 309 | & rt_hash_mask; |
1da177e4 LT |
310 | } |
311 | ||
e84f84f2 DL |
312 | static inline int rt_genid(struct net *net) |
313 | { | |
314 | return atomic_read(&net->ipv4.rt_genid); | |
315 | } | |
316 | ||
1da177e4 LT |
317 | #ifdef CONFIG_PROC_FS |
318 | struct rt_cache_iter_state { | |
a75e936f | 319 | struct seq_net_private p; |
1da177e4 | 320 | int bucket; |
29e75252 | 321 | int genid; |
1da177e4 LT |
322 | }; |
323 | ||
1218854a | 324 | static struct rtable *rt_cache_get_first(struct seq_file *seq) |
1da177e4 | 325 | { |
1218854a | 326 | struct rt_cache_iter_state *st = seq->private; |
1da177e4 | 327 | struct rtable *r = NULL; |
1da177e4 LT |
328 | |
329 | for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) { | |
33d480ce | 330 | if (!rcu_access_pointer(rt_hash_table[st->bucket].chain)) |
a6272665 | 331 | continue; |
1da177e4 | 332 | rcu_read_lock_bh(); |
a898def2 | 333 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
29e75252 | 334 | while (r) { |
d8d1f30b | 335 | if (dev_net(r->dst.dev) == seq_file_net(seq) && |
a75e936f | 336 | r->rt_genid == st->genid) |
29e75252 | 337 | return r; |
d8d1f30b | 338 | r = rcu_dereference_bh(r->dst.rt_next); |
29e75252 | 339 | } |
1da177e4 LT |
340 | rcu_read_unlock_bh(); |
341 | } | |
29e75252 | 342 | return r; |
1da177e4 LT |
343 | } |
344 | ||
1218854a | 345 | static struct rtable *__rt_cache_get_next(struct seq_file *seq, |
642d6318 | 346 | struct rtable *r) |
1da177e4 | 347 | { |
1218854a | 348 | struct rt_cache_iter_state *st = seq->private; |
a6272665 | 349 | |
1c31720a | 350 | r = rcu_dereference_bh(r->dst.rt_next); |
1da177e4 LT |
351 | while (!r) { |
352 | rcu_read_unlock_bh(); | |
a6272665 ED |
353 | do { |
354 | if (--st->bucket < 0) | |
355 | return NULL; | |
33d480ce | 356 | } while (!rcu_access_pointer(rt_hash_table[st->bucket].chain)); |
1da177e4 | 357 | rcu_read_lock_bh(); |
1c31720a | 358 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
1da177e4 | 359 | } |
1c31720a | 360 | return r; |
1da177e4 LT |
361 | } |
362 | ||
1218854a | 363 | static struct rtable *rt_cache_get_next(struct seq_file *seq, |
642d6318 DL |
364 | struct rtable *r) |
365 | { | |
1218854a YH |
366 | struct rt_cache_iter_state *st = seq->private; |
367 | while ((r = __rt_cache_get_next(seq, r)) != NULL) { | |
d8d1f30b | 368 | if (dev_net(r->dst.dev) != seq_file_net(seq)) |
a75e936f | 369 | continue; |
642d6318 DL |
370 | if (r->rt_genid == st->genid) |
371 | break; | |
372 | } | |
373 | return r; | |
374 | } | |
375 | ||
1218854a | 376 | static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 377 | { |
1218854a | 378 | struct rtable *r = rt_cache_get_first(seq); |
1da177e4 LT |
379 | |
380 | if (r) | |
1218854a | 381 | while (pos && (r = rt_cache_get_next(seq, r))) |
1da177e4 LT |
382 | --pos; |
383 | return pos ? NULL : r; | |
384 | } | |
385 | ||
386 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) | |
387 | { | |
29e75252 | 388 | struct rt_cache_iter_state *st = seq->private; |
29e75252 | 389 | if (*pos) |
1218854a | 390 | return rt_cache_get_idx(seq, *pos - 1); |
e84f84f2 | 391 | st->genid = rt_genid(seq_file_net(seq)); |
29e75252 | 392 | return SEQ_START_TOKEN; |
1da177e4 LT |
393 | } |
394 | ||
395 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
396 | { | |
29e75252 | 397 | struct rtable *r; |
1da177e4 LT |
398 | |
399 | if (v == SEQ_START_TOKEN) | |
1218854a | 400 | r = rt_cache_get_first(seq); |
1da177e4 | 401 | else |
1218854a | 402 | r = rt_cache_get_next(seq, v); |
1da177e4 LT |
403 | ++*pos; |
404 | return r; | |
405 | } | |
406 | ||
407 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
408 | { | |
409 | if (v && v != SEQ_START_TOKEN) | |
410 | rcu_read_unlock_bh(); | |
411 | } | |
412 | ||
413 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
414 | { | |
415 | if (v == SEQ_START_TOKEN) | |
416 | seq_printf(seq, "%-127s\n", | |
417 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
418 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
419 | "HHUptod\tSpecDst"); | |
420 | else { | |
421 | struct rtable *r = v; | |
69cce1d1 | 422 | struct neighbour *n; |
218fa90f | 423 | int len, HHUptod; |
1da177e4 | 424 | |
218fa90f | 425 | rcu_read_lock(); |
27217455 | 426 | n = dst_get_neighbour_noref(&r->dst); |
218fa90f ED |
427 | HHUptod = (n && (n->nud_state & NUD_CONNECTED)) ? 1 : 0; |
428 | rcu_read_unlock(); | |
429 | ||
0eae88f3 ED |
430 | seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t" |
431 | "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n", | |
d8d1f30b | 432 | r->dst.dev ? r->dst.dev->name : "*", |
0eae88f3 ED |
433 | (__force u32)r->rt_dst, |
434 | (__force u32)r->rt_gateway, | |
d8d1f30b CG |
435 | r->rt_flags, atomic_read(&r->dst.__refcnt), |
436 | r->dst.__use, 0, (__force u32)r->rt_src, | |
0dbaee3b | 437 | dst_metric_advmss(&r->dst) + 40, |
d8d1f30b CG |
438 | dst_metric(&r->dst, RTAX_WINDOW), |
439 | (int)((dst_metric(&r->dst, RTAX_RTT) >> 3) + | |
440 | dst_metric(&r->dst, RTAX_RTTVAR)), | |
475949d8 | 441 | r->rt_key_tos, |
f6b72b62 | 442 | -1, |
218fa90f | 443 | HHUptod, |
5e659e4c PE |
444 | r->rt_spec_dst, &len); |
445 | ||
446 | seq_printf(seq, "%*s\n", 127 - len, ""); | |
e905a9ed YH |
447 | } |
448 | return 0; | |
1da177e4 LT |
449 | } |
450 | ||
f690808e | 451 | static const struct seq_operations rt_cache_seq_ops = { |
1da177e4 LT |
452 | .start = rt_cache_seq_start, |
453 | .next = rt_cache_seq_next, | |
454 | .stop = rt_cache_seq_stop, | |
455 | .show = rt_cache_seq_show, | |
456 | }; | |
457 | ||
458 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
459 | { | |
a75e936f | 460 | return seq_open_net(inode, file, &rt_cache_seq_ops, |
cf7732e4 | 461 | sizeof(struct rt_cache_iter_state)); |
1da177e4 LT |
462 | } |
463 | ||
9a32144e | 464 | static const struct file_operations rt_cache_seq_fops = { |
1da177e4 LT |
465 | .owner = THIS_MODULE, |
466 | .open = rt_cache_seq_open, | |
467 | .read = seq_read, | |
468 | .llseek = seq_lseek, | |
a75e936f | 469 | .release = seq_release_net, |
1da177e4 LT |
470 | }; |
471 | ||
472 | ||
473 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
474 | { | |
475 | int cpu; | |
476 | ||
477 | if (*pos == 0) | |
478 | return SEQ_START_TOKEN; | |
479 | ||
0f23174a | 480 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
481 | if (!cpu_possible(cpu)) |
482 | continue; | |
483 | *pos = cpu+1; | |
2f970d83 | 484 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
485 | } |
486 | return NULL; | |
487 | } | |
488 | ||
489 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
490 | { | |
491 | int cpu; | |
492 | ||
0f23174a | 493 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
494 | if (!cpu_possible(cpu)) |
495 | continue; | |
496 | *pos = cpu+1; | |
2f970d83 | 497 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
498 | } |
499 | return NULL; | |
e905a9ed | 500 | |
1da177e4 LT |
501 | } |
502 | ||
503 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
504 | { | |
505 | ||
506 | } | |
507 | ||
508 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
509 | { | |
510 | struct rt_cache_stat *st = v; | |
511 | ||
512 | if (v == SEQ_START_TOKEN) { | |
5bec0039 | 513 | seq_printf(seq, "entries in_hit in_slow_tot in_slow_mc in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n"); |
1da177e4 LT |
514 | return 0; |
515 | } | |
e905a9ed | 516 | |
1da177e4 LT |
517 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " |
518 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
fc66f95c | 519 | dst_entries_get_slow(&ipv4_dst_ops), |
1da177e4 LT |
520 | st->in_hit, |
521 | st->in_slow_tot, | |
522 | st->in_slow_mc, | |
523 | st->in_no_route, | |
524 | st->in_brd, | |
525 | st->in_martian_dst, | |
526 | st->in_martian_src, | |
527 | ||
528 | st->out_hit, | |
529 | st->out_slow_tot, | |
e905a9ed | 530 | st->out_slow_mc, |
1da177e4 LT |
531 | |
532 | st->gc_total, | |
533 | st->gc_ignored, | |
534 | st->gc_goal_miss, | |
535 | st->gc_dst_overflow, | |
536 | st->in_hlist_search, | |
537 | st->out_hlist_search | |
538 | ); | |
539 | return 0; | |
540 | } | |
541 | ||
f690808e | 542 | static const struct seq_operations rt_cpu_seq_ops = { |
1da177e4 LT |
543 | .start = rt_cpu_seq_start, |
544 | .next = rt_cpu_seq_next, | |
545 | .stop = rt_cpu_seq_stop, | |
546 | .show = rt_cpu_seq_show, | |
547 | }; | |
548 | ||
549 | ||
550 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
551 | { | |
552 | return seq_open(file, &rt_cpu_seq_ops); | |
553 | } | |
554 | ||
9a32144e | 555 | static const struct file_operations rt_cpu_seq_fops = { |
1da177e4 LT |
556 | .owner = THIS_MODULE, |
557 | .open = rt_cpu_seq_open, | |
558 | .read = seq_read, | |
559 | .llseek = seq_lseek, | |
560 | .release = seq_release, | |
561 | }; | |
562 | ||
c7066f70 | 563 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 564 | static int rt_acct_proc_show(struct seq_file *m, void *v) |
78c686e9 | 565 | { |
a661c419 AD |
566 | struct ip_rt_acct *dst, *src; |
567 | unsigned int i, j; | |
568 | ||
569 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
570 | if (!dst) | |
571 | return -ENOMEM; | |
572 | ||
573 | for_each_possible_cpu(i) { | |
574 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
575 | for (j = 0; j < 256; j++) { | |
576 | dst[j].o_bytes += src[j].o_bytes; | |
577 | dst[j].o_packets += src[j].o_packets; | |
578 | dst[j].i_bytes += src[j].i_bytes; | |
579 | dst[j].i_packets += src[j].i_packets; | |
580 | } | |
78c686e9 PE |
581 | } |
582 | ||
a661c419 AD |
583 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); |
584 | kfree(dst); | |
585 | return 0; | |
586 | } | |
78c686e9 | 587 | |
a661c419 AD |
588 | static int rt_acct_proc_open(struct inode *inode, struct file *file) |
589 | { | |
590 | return single_open(file, rt_acct_proc_show, NULL); | |
78c686e9 | 591 | } |
a661c419 AD |
592 | |
593 | static const struct file_operations rt_acct_proc_fops = { | |
594 | .owner = THIS_MODULE, | |
595 | .open = rt_acct_proc_open, | |
596 | .read = seq_read, | |
597 | .llseek = seq_lseek, | |
598 | .release = single_release, | |
599 | }; | |
78c686e9 | 600 | #endif |
107f1634 | 601 | |
73b38711 | 602 | static int __net_init ip_rt_do_proc_init(struct net *net) |
107f1634 PE |
603 | { |
604 | struct proc_dir_entry *pde; | |
605 | ||
606 | pde = proc_net_fops_create(net, "rt_cache", S_IRUGO, | |
607 | &rt_cache_seq_fops); | |
608 | if (!pde) | |
609 | goto err1; | |
610 | ||
77020720 WC |
611 | pde = proc_create("rt_cache", S_IRUGO, |
612 | net->proc_net_stat, &rt_cpu_seq_fops); | |
107f1634 PE |
613 | if (!pde) |
614 | goto err2; | |
615 | ||
c7066f70 | 616 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 617 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); |
107f1634 PE |
618 | if (!pde) |
619 | goto err3; | |
620 | #endif | |
621 | return 0; | |
622 | ||
c7066f70 | 623 | #ifdef CONFIG_IP_ROUTE_CLASSID |
107f1634 PE |
624 | err3: |
625 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
626 | #endif | |
627 | err2: | |
628 | remove_proc_entry("rt_cache", net->proc_net); | |
629 | err1: | |
630 | return -ENOMEM; | |
631 | } | |
73b38711 DL |
632 | |
633 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
634 | { | |
635 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
636 | remove_proc_entry("rt_cache", net->proc_net); | |
c7066f70 | 637 | #ifdef CONFIG_IP_ROUTE_CLASSID |
73b38711 | 638 | remove_proc_entry("rt_acct", net->proc_net); |
0a931acf | 639 | #endif |
73b38711 DL |
640 | } |
641 | ||
642 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
643 | .init = ip_rt_do_proc_init, | |
644 | .exit = ip_rt_do_proc_exit, | |
645 | }; | |
646 | ||
647 | static int __init ip_rt_proc_init(void) | |
648 | { | |
649 | return register_pernet_subsys(&ip_rt_proc_ops); | |
650 | } | |
651 | ||
107f1634 | 652 | #else |
73b38711 | 653 | static inline int ip_rt_proc_init(void) |
107f1634 PE |
654 | { |
655 | return 0; | |
656 | } | |
1da177e4 | 657 | #endif /* CONFIG_PROC_FS */ |
e905a9ed | 658 | |
5969f71d | 659 | static inline void rt_free(struct rtable *rt) |
1da177e4 | 660 | { |
d8d1f30b | 661 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
662 | } |
663 | ||
5969f71d | 664 | static inline void rt_drop(struct rtable *rt) |
1da177e4 | 665 | { |
1da177e4 | 666 | ip_rt_put(rt); |
d8d1f30b | 667 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
668 | } |
669 | ||
5969f71d | 670 | static inline int rt_fast_clean(struct rtable *rth) |
1da177e4 LT |
671 | { |
672 | /* Kill broadcast/multicast entries very aggresively, if they | |
673 | collide in hash table with more useful entries */ | |
674 | return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) && | |
c7537967 | 675 | rt_is_input_route(rth) && rth->dst.rt_next; |
1da177e4 LT |
676 | } |
677 | ||
5969f71d | 678 | static inline int rt_valuable(struct rtable *rth) |
1da177e4 LT |
679 | { |
680 | return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || | |
2c8cec5c | 681 | (rth->peer && rth->peer->pmtu_expires); |
1da177e4 LT |
682 | } |
683 | ||
684 | static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) | |
685 | { | |
686 | unsigned long age; | |
687 | int ret = 0; | |
688 | ||
d8d1f30b | 689 | if (atomic_read(&rth->dst.__refcnt)) |
1da177e4 LT |
690 | goto out; |
691 | ||
d8d1f30b | 692 | age = jiffies - rth->dst.lastuse; |
1da177e4 LT |
693 | if ((age <= tmo1 && !rt_fast_clean(rth)) || |
694 | (age <= tmo2 && rt_valuable(rth))) | |
695 | goto out; | |
696 | ret = 1; | |
697 | out: return ret; | |
698 | } | |
699 | ||
700 | /* Bits of score are: | |
701 | * 31: very valuable | |
702 | * 30: not quite useless | |
703 | * 29..0: usage counter | |
704 | */ | |
705 | static inline u32 rt_score(struct rtable *rt) | |
706 | { | |
d8d1f30b | 707 | u32 score = jiffies - rt->dst.lastuse; |
1da177e4 LT |
708 | |
709 | score = ~score & ~(3<<30); | |
710 | ||
711 | if (rt_valuable(rt)) | |
712 | score |= (1<<31); | |
713 | ||
c7537967 | 714 | if (rt_is_output_route(rt) || |
1da177e4 LT |
715 | !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL))) |
716 | score |= (1<<30); | |
717 | ||
718 | return score; | |
719 | } | |
720 | ||
1080d709 NH |
721 | static inline bool rt_caching(const struct net *net) |
722 | { | |
723 | return net->ipv4.current_rt_cache_rebuild_count <= | |
724 | net->ipv4.sysctl_rt_cache_rebuild_count; | |
725 | } | |
726 | ||
5e2b61f7 DM |
727 | static inline bool compare_hash_inputs(const struct rtable *rt1, |
728 | const struct rtable *rt2) | |
1080d709 | 729 | { |
5e2b61f7 DM |
730 | return ((((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
731 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
97a80410 | 732 | (rt1->rt_route_iif ^ rt2->rt_route_iif)) == 0); |
1080d709 NH |
733 | } |
734 | ||
5e2b61f7 | 735 | static inline int compare_keys(struct rtable *rt1, struct rtable *rt2) |
1da177e4 | 736 | { |
5e2b61f7 DM |
737 | return (((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
738 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
739 | (rt1->rt_mark ^ rt2->rt_mark) | | |
475949d8 | 740 | (rt1->rt_key_tos ^ rt2->rt_key_tos) | |
d547f727 | 741 | (rt1->rt_route_iif ^ rt2->rt_route_iif) | |
97a80410 | 742 | (rt1->rt_oif ^ rt2->rt_oif)) == 0; |
1da177e4 LT |
743 | } |
744 | ||
b5921910 DL |
745 | static inline int compare_netns(struct rtable *rt1, struct rtable *rt2) |
746 | { | |
d8d1f30b | 747 | return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev)); |
b5921910 DL |
748 | } |
749 | ||
e84f84f2 DL |
750 | static inline int rt_is_expired(struct rtable *rth) |
751 | { | |
d8d1f30b | 752 | return rth->rt_genid != rt_genid(dev_net(rth->dst.dev)); |
e84f84f2 DL |
753 | } |
754 | ||
beb659bd ED |
755 | /* |
756 | * Perform a full scan of hash table and free all entries. | |
757 | * Can be called by a softirq or a process. | |
758 | * In the later case, we want to be reschedule if necessary | |
759 | */ | |
6561a3b1 | 760 | static void rt_do_flush(struct net *net, int process_context) |
beb659bd ED |
761 | { |
762 | unsigned int i; | |
763 | struct rtable *rth, *next; | |
764 | ||
765 | for (i = 0; i <= rt_hash_mask; i++) { | |
6561a3b1 DM |
766 | struct rtable __rcu **pprev; |
767 | struct rtable *list; | |
768 | ||
beb659bd ED |
769 | if (process_context && need_resched()) |
770 | cond_resched(); | |
33d480ce | 771 | rth = rcu_access_pointer(rt_hash_table[i].chain); |
beb659bd ED |
772 | if (!rth) |
773 | continue; | |
774 | ||
775 | spin_lock_bh(rt_hash_lock_addr(i)); | |
32cb5b4e | 776 | |
6561a3b1 DM |
777 | list = NULL; |
778 | pprev = &rt_hash_table[i].chain; | |
779 | rth = rcu_dereference_protected(*pprev, | |
1c31720a | 780 | lockdep_is_held(rt_hash_lock_addr(i))); |
32cb5b4e | 781 | |
6561a3b1 DM |
782 | while (rth) { |
783 | next = rcu_dereference_protected(rth->dst.rt_next, | |
1c31720a | 784 | lockdep_is_held(rt_hash_lock_addr(i))); |
6561a3b1 DM |
785 | |
786 | if (!net || | |
787 | net_eq(dev_net(rth->dst.dev), net)) { | |
788 | rcu_assign_pointer(*pprev, next); | |
789 | rcu_assign_pointer(rth->dst.rt_next, list); | |
790 | list = rth; | |
32cb5b4e | 791 | } else { |
6561a3b1 | 792 | pprev = &rth->dst.rt_next; |
32cb5b4e | 793 | } |
6561a3b1 | 794 | rth = next; |
32cb5b4e | 795 | } |
6561a3b1 | 796 | |
beb659bd ED |
797 | spin_unlock_bh(rt_hash_lock_addr(i)); |
798 | ||
6561a3b1 DM |
799 | for (; list; list = next) { |
800 | next = rcu_dereference_protected(list->dst.rt_next, 1); | |
801 | rt_free(list); | |
beb659bd ED |
802 | } |
803 | } | |
804 | } | |
805 | ||
1080d709 NH |
806 | /* |
807 | * While freeing expired entries, we compute average chain length | |
808 | * and standard deviation, using fixed-point arithmetic. | |
809 | * This to have an estimation of rt_chain_length_max | |
810 | * rt_chain_length_max = max(elasticity, AVG + 4*SD) | |
811 | * We use 3 bits for frational part, and 29 (or 61) for magnitude. | |
812 | */ | |
813 | ||
814 | #define FRACT_BITS 3 | |
815 | #define ONE (1UL << FRACT_BITS) | |
816 | ||
98376387 ED |
817 | /* |
818 | * Given a hash chain and an item in this hash chain, | |
819 | * find if a previous entry has the same hash_inputs | |
820 | * (but differs on tos, mark or oif) | |
821 | * Returns 0 if an alias is found. | |
822 | * Returns ONE if rth has no alias before itself. | |
823 | */ | |
824 | static int has_noalias(const struct rtable *head, const struct rtable *rth) | |
825 | { | |
826 | const struct rtable *aux = head; | |
827 | ||
828 | while (aux != rth) { | |
5e2b61f7 | 829 | if (compare_hash_inputs(aux, rth)) |
98376387 | 830 | return 0; |
1c31720a | 831 | aux = rcu_dereference_protected(aux->dst.rt_next, 1); |
98376387 ED |
832 | } |
833 | return ONE; | |
834 | } | |
835 | ||
9f28a2fc ED |
836 | static void rt_check_expire(void) |
837 | { | |
838 | static unsigned int rover; | |
839 | unsigned int i = rover, goal; | |
840 | struct rtable *rth; | |
841 | struct rtable __rcu **rthp; | |
842 | unsigned long samples = 0; | |
843 | unsigned long sum = 0, sum2 = 0; | |
844 | unsigned long delta; | |
845 | u64 mult; | |
846 | ||
847 | delta = jiffies - expires_ljiffies; | |
848 | expires_ljiffies = jiffies; | |
849 | mult = ((u64)delta) << rt_hash_log; | |
850 | if (ip_rt_gc_timeout > 1) | |
851 | do_div(mult, ip_rt_gc_timeout); | |
852 | goal = (unsigned int)mult; | |
853 | if (goal > rt_hash_mask) | |
854 | goal = rt_hash_mask + 1; | |
855 | for (; goal > 0; goal--) { | |
856 | unsigned long tmo = ip_rt_gc_timeout; | |
857 | unsigned long length; | |
858 | ||
859 | i = (i + 1) & rt_hash_mask; | |
860 | rthp = &rt_hash_table[i].chain; | |
861 | ||
862 | if (need_resched()) | |
863 | cond_resched(); | |
864 | ||
865 | samples++; | |
866 | ||
867 | if (rcu_dereference_raw(*rthp) == NULL) | |
868 | continue; | |
869 | length = 0; | |
870 | spin_lock_bh(rt_hash_lock_addr(i)); | |
871 | while ((rth = rcu_dereference_protected(*rthp, | |
872 | lockdep_is_held(rt_hash_lock_addr(i)))) != NULL) { | |
873 | prefetch(rth->dst.rt_next); | |
874 | if (rt_is_expired(rth)) { | |
875 | *rthp = rth->dst.rt_next; | |
876 | rt_free(rth); | |
877 | continue; | |
878 | } | |
879 | if (rth->dst.expires) { | |
880 | /* Entry is expired even if it is in use */ | |
881 | if (time_before_eq(jiffies, rth->dst.expires)) { | |
882 | nofree: | |
883 | tmo >>= 1; | |
884 | rthp = &rth->dst.rt_next; | |
885 | /* | |
886 | * We only count entries on | |
887 | * a chain with equal hash inputs once | |
888 | * so that entries for different QOS | |
889 | * levels, and other non-hash input | |
890 | * attributes don't unfairly skew | |
891 | * the length computation | |
892 | */ | |
893 | length += has_noalias(rt_hash_table[i].chain, rth); | |
894 | continue; | |
895 | } | |
896 | } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) | |
897 | goto nofree; | |
898 | ||
899 | /* Cleanup aged off entries. */ | |
900 | *rthp = rth->dst.rt_next; | |
901 | rt_free(rth); | |
902 | } | |
903 | spin_unlock_bh(rt_hash_lock_addr(i)); | |
904 | sum += length; | |
905 | sum2 += length*length; | |
906 | } | |
907 | if (samples) { | |
908 | unsigned long avg = sum / samples; | |
909 | unsigned long sd = int_sqrt(sum2 / samples - avg*avg); | |
910 | rt_chain_length_max = max_t(unsigned long, | |
911 | ip_rt_gc_elasticity, | |
912 | (avg + 4*sd) >> FRACT_BITS); | |
913 | } | |
914 | rover = i; | |
915 | } | |
916 | ||
917 | /* | |
918 | * rt_worker_func() is run in process context. | |
919 | * we call rt_check_expire() to scan part of the hash table | |
920 | */ | |
921 | static void rt_worker_func(struct work_struct *work) | |
922 | { | |
923 | rt_check_expire(); | |
924 | schedule_delayed_work(&expires_work, ip_rt_gc_interval); | |
925 | } | |
926 | ||
29e75252 | 927 | /* |
25985edc | 928 | * Perturbation of rt_genid by a small quantity [1..256] |
29e75252 ED |
929 | * Using 8 bits of shuffling ensure we can call rt_cache_invalidate() |
930 | * many times (2^24) without giving recent rt_genid. | |
931 | * Jenkins hash is strong enough that litle changes of rt_genid are OK. | |
1da177e4 | 932 | */ |
86c657f6 | 933 | static void rt_cache_invalidate(struct net *net) |
1da177e4 | 934 | { |
29e75252 | 935 | unsigned char shuffle; |
1da177e4 | 936 | |
29e75252 | 937 | get_random_bytes(&shuffle, sizeof(shuffle)); |
e84f84f2 | 938 | atomic_add(shuffle + 1U, &net->ipv4.rt_genid); |
5faa5df1 | 939 | inetpeer_invalidate_tree(AF_INET); |
1da177e4 LT |
940 | } |
941 | ||
29e75252 ED |
942 | /* |
943 | * delay < 0 : invalidate cache (fast : entries will be deleted later) | |
944 | * delay >= 0 : invalidate & flush cache (can be long) | |
945 | */ | |
76e6ebfb | 946 | void rt_cache_flush(struct net *net, int delay) |
1da177e4 | 947 | { |
86c657f6 | 948 | rt_cache_invalidate(net); |
29e75252 | 949 | if (delay >= 0) |
6561a3b1 | 950 | rt_do_flush(net, !in_softirq()); |
1da177e4 LT |
951 | } |
952 | ||
a5ee1551 | 953 | /* Flush previous cache invalidated entries from the cache */ |
6561a3b1 | 954 | void rt_cache_flush_batch(struct net *net) |
a5ee1551 | 955 | { |
6561a3b1 | 956 | rt_do_flush(net, !in_softirq()); |
a5ee1551 EB |
957 | } |
958 | ||
1080d709 NH |
959 | static void rt_emergency_hash_rebuild(struct net *net) |
960 | { | |
3ee94372 | 961 | if (net_ratelimit()) |
058bd4d2 | 962 | pr_warn("Route hash chain too long!\n"); |
3ee94372 | 963 | rt_cache_invalidate(net); |
1080d709 NH |
964 | } |
965 | ||
1da177e4 LT |
966 | /* |
967 | Short description of GC goals. | |
968 | ||
969 | We want to build algorithm, which will keep routing cache | |
970 | at some equilibrium point, when number of aged off entries | |
971 | is kept approximately equal to newly generated ones. | |
972 | ||
973 | Current expiration strength is variable "expire". | |
974 | We try to adjust it dynamically, so that if networking | |
975 | is idle expires is large enough to keep enough of warm entries, | |
976 | and when load increases it reduces to limit cache size. | |
977 | */ | |
978 | ||
569d3645 | 979 | static int rt_garbage_collect(struct dst_ops *ops) |
1da177e4 LT |
980 | { |
981 | static unsigned long expire = RT_GC_TIMEOUT; | |
982 | static unsigned long last_gc; | |
983 | static int rover; | |
984 | static int equilibrium; | |
1c31720a ED |
985 | struct rtable *rth; |
986 | struct rtable __rcu **rthp; | |
1da177e4 LT |
987 | unsigned long now = jiffies; |
988 | int goal; | |
fc66f95c | 989 | int entries = dst_entries_get_fast(&ipv4_dst_ops); |
1da177e4 LT |
990 | |
991 | /* | |
992 | * Garbage collection is pretty expensive, | |
993 | * do not make it too frequently. | |
994 | */ | |
995 | ||
996 | RT_CACHE_STAT_INC(gc_total); | |
997 | ||
998 | if (now - last_gc < ip_rt_gc_min_interval && | |
fc66f95c | 999 | entries < ip_rt_max_size) { |
1da177e4 LT |
1000 | RT_CACHE_STAT_INC(gc_ignored); |
1001 | goto out; | |
1002 | } | |
1003 | ||
fc66f95c | 1004 | entries = dst_entries_get_slow(&ipv4_dst_ops); |
1da177e4 | 1005 | /* Calculate number of entries, which we want to expire now. */ |
fc66f95c | 1006 | goal = entries - (ip_rt_gc_elasticity << rt_hash_log); |
1da177e4 LT |
1007 | if (goal <= 0) { |
1008 | if (equilibrium < ipv4_dst_ops.gc_thresh) | |
1009 | equilibrium = ipv4_dst_ops.gc_thresh; | |
fc66f95c | 1010 | goal = entries - equilibrium; |
1da177e4 | 1011 | if (goal > 0) { |
b790cedd | 1012 | equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 1013 | goal = entries - equilibrium; |
1da177e4 LT |
1014 | } |
1015 | } else { | |
1016 | /* We are in dangerous area. Try to reduce cache really | |
1017 | * aggressively. | |
1018 | */ | |
b790cedd | 1019 | goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 1020 | equilibrium = entries - goal; |
1da177e4 LT |
1021 | } |
1022 | ||
1023 | if (now - last_gc >= ip_rt_gc_min_interval) | |
1024 | last_gc = now; | |
1025 | ||
1026 | if (goal <= 0) { | |
1027 | equilibrium += goal; | |
1028 | goto work_done; | |
1029 | } | |
1030 | ||
1031 | do { | |
1032 | int i, k; | |
1033 | ||
1034 | for (i = rt_hash_mask, k = rover; i >= 0; i--) { | |
1035 | unsigned long tmo = expire; | |
1036 | ||
1037 | k = (k + 1) & rt_hash_mask; | |
1038 | rthp = &rt_hash_table[k].chain; | |
22c047cc | 1039 | spin_lock_bh(rt_hash_lock_addr(k)); |
1c31720a ED |
1040 | while ((rth = rcu_dereference_protected(*rthp, |
1041 | lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) { | |
e84f84f2 | 1042 | if (!rt_is_expired(rth) && |
29e75252 | 1043 | !rt_may_expire(rth, tmo, expire)) { |
1da177e4 | 1044 | tmo >>= 1; |
d8d1f30b | 1045 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1046 | continue; |
1047 | } | |
d8d1f30b | 1048 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1049 | rt_free(rth); |
1050 | goal--; | |
1da177e4 | 1051 | } |
22c047cc | 1052 | spin_unlock_bh(rt_hash_lock_addr(k)); |
1da177e4 LT |
1053 | if (goal <= 0) |
1054 | break; | |
1055 | } | |
1056 | rover = k; | |
1057 | ||
1058 | if (goal <= 0) | |
1059 | goto work_done; | |
1060 | ||
1061 | /* Goal is not achieved. We stop process if: | |
1062 | ||
1063 | - if expire reduced to zero. Otherwise, expire is halfed. | |
1064 | - if table is not full. | |
1065 | - if we are called from interrupt. | |
1066 | - jiffies check is just fallback/debug loop breaker. | |
1067 | We will not spin here for long time in any case. | |
1068 | */ | |
1069 | ||
1070 | RT_CACHE_STAT_INC(gc_goal_miss); | |
1071 | ||
1072 | if (expire == 0) | |
1073 | break; | |
1074 | ||
1075 | expire >>= 1; | |
1da177e4 | 1076 | |
fc66f95c | 1077 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1da177e4 LT |
1078 | goto out; |
1079 | } while (!in_softirq() && time_before_eq(jiffies, now)); | |
1080 | ||
fc66f95c ED |
1081 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1082 | goto out; | |
1083 | if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size) | |
1da177e4 LT |
1084 | goto out; |
1085 | if (net_ratelimit()) | |
058bd4d2 | 1086 | pr_warn("dst cache overflow\n"); |
1da177e4 LT |
1087 | RT_CACHE_STAT_INC(gc_dst_overflow); |
1088 | return 1; | |
1089 | ||
1090 | work_done: | |
1091 | expire += ip_rt_gc_min_interval; | |
1092 | if (expire > ip_rt_gc_timeout || | |
fc66f95c ED |
1093 | dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh || |
1094 | dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh) | |
1da177e4 | 1095 | expire = ip_rt_gc_timeout; |
1da177e4 LT |
1096 | out: return 0; |
1097 | } | |
1098 | ||
98376387 ED |
1099 | /* |
1100 | * Returns number of entries in a hash chain that have different hash_inputs | |
1101 | */ | |
1102 | static int slow_chain_length(const struct rtable *head) | |
1103 | { | |
1104 | int length = 0; | |
1105 | const struct rtable *rth = head; | |
1106 | ||
1107 | while (rth) { | |
1108 | length += has_noalias(head, rth); | |
1c31720a | 1109 | rth = rcu_dereference_protected(rth->dst.rt_next, 1); |
98376387 ED |
1110 | } |
1111 | return length >> FRACT_BITS; | |
1112 | } | |
1113 | ||
d3aaeb38 | 1114 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr) |
3769cffb | 1115 | { |
d3aaeb38 DM |
1116 | static const __be32 inaddr_any = 0; |
1117 | struct net_device *dev = dst->dev; | |
1118 | const __be32 *pkey = daddr; | |
39232973 | 1119 | const struct rtable *rt; |
3769cffb DM |
1120 | struct neighbour *n; |
1121 | ||
39232973 DM |
1122 | rt = (const struct rtable *) dst; |
1123 | ||
3769cffb | 1124 | if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) |
d3aaeb38 | 1125 | pkey = &inaddr_any; |
39232973 DM |
1126 | else if (rt->rt_gateway) |
1127 | pkey = (const __be32 *) &rt->rt_gateway; | |
d3aaeb38 | 1128 | |
80703d26 | 1129 | n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey); |
d3aaeb38 DM |
1130 | if (n) |
1131 | return n; | |
32092ecf | 1132 | return neigh_create(&arp_tbl, pkey, dev); |
d3aaeb38 DM |
1133 | } |
1134 | ||
1135 | static int rt_bind_neighbour(struct rtable *rt) | |
1136 | { | |
1137 | struct neighbour *n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway); | |
3769cffb DM |
1138 | if (IS_ERR(n)) |
1139 | return PTR_ERR(n); | |
69cce1d1 | 1140 | dst_set_neighbour(&rt->dst, n); |
3769cffb DM |
1141 | |
1142 | return 0; | |
1143 | } | |
1144 | ||
b23dd4fe DM |
1145 | static struct rtable *rt_intern_hash(unsigned hash, struct rtable *rt, |
1146 | struct sk_buff *skb, int ifindex) | |
1da177e4 | 1147 | { |
1c31720a ED |
1148 | struct rtable *rth, *cand; |
1149 | struct rtable __rcu **rthp, **candp; | |
1da177e4 | 1150 | unsigned long now; |
1da177e4 LT |
1151 | u32 min_score; |
1152 | int chain_length; | |
1153 | int attempts = !in_softirq(); | |
1154 | ||
1155 | restart: | |
1156 | chain_length = 0; | |
1157 | min_score = ~(u32)0; | |
1158 | cand = NULL; | |
1159 | candp = NULL; | |
1160 | now = jiffies; | |
1161 | ||
d8d1f30b | 1162 | if (!rt_caching(dev_net(rt->dst.dev))) { |
73e42897 NH |
1163 | /* |
1164 | * If we're not caching, just tell the caller we | |
1165 | * were successful and don't touch the route. The | |
1166 | * caller hold the sole reference to the cache entry, and | |
1167 | * it will be released when the caller is done with it. | |
1168 | * If we drop it here, the callers have no way to resolve routes | |
1169 | * when we're not caching. Instead, just point *rp at rt, so | |
1170 | * the caller gets a single use out of the route | |
b6280b47 NH |
1171 | * Note that we do rt_free on this new route entry, so that |
1172 | * once its refcount hits zero, we are still able to reap it | |
1173 | * (Thanks Alexey) | |
27b75c95 ED |
1174 | * Note: To avoid expensive rcu stuff for this uncached dst, |
1175 | * we set DST_NOCACHE so that dst_release() can free dst without | |
1176 | * waiting a grace period. | |
73e42897 | 1177 | */ |
b6280b47 | 1178 | |
c7d4426a | 1179 | rt->dst.flags |= DST_NOCACHE; |
c7537967 | 1180 | if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) { |
3769cffb | 1181 | int err = rt_bind_neighbour(rt); |
b6280b47 NH |
1182 | if (err) { |
1183 | if (net_ratelimit()) | |
058bd4d2 | 1184 | pr_warn("Neighbour table failure & not caching routes\n"); |
27b75c95 | 1185 | ip_rt_put(rt); |
b23dd4fe | 1186 | return ERR_PTR(err); |
b6280b47 NH |
1187 | } |
1188 | } | |
1189 | ||
b6280b47 | 1190 | goto skip_hashing; |
1080d709 NH |
1191 | } |
1192 | ||
1da177e4 LT |
1193 | rthp = &rt_hash_table[hash].chain; |
1194 | ||
22c047cc | 1195 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1c31720a ED |
1196 | while ((rth = rcu_dereference_protected(*rthp, |
1197 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1198 | if (rt_is_expired(rth)) { |
d8d1f30b | 1199 | *rthp = rth->dst.rt_next; |
29e75252 ED |
1200 | rt_free(rth); |
1201 | continue; | |
1202 | } | |
5e2b61f7 | 1203 | if (compare_keys(rth, rt) && compare_netns(rth, rt)) { |
1da177e4 | 1204 | /* Put it first */ |
d8d1f30b | 1205 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1206 | /* |
1207 | * Since lookup is lockfree, the deletion | |
1208 | * must be visible to another weakly ordered CPU before | |
1209 | * the insertion at the start of the hash chain. | |
1210 | */ | |
d8d1f30b | 1211 | rcu_assign_pointer(rth->dst.rt_next, |
1da177e4 LT |
1212 | rt_hash_table[hash].chain); |
1213 | /* | |
1214 | * Since lookup is lockfree, the update writes | |
1215 | * must be ordered for consistency on SMP. | |
1216 | */ | |
1217 | rcu_assign_pointer(rt_hash_table[hash].chain, rth); | |
1218 | ||
d8d1f30b | 1219 | dst_use(&rth->dst, now); |
22c047cc | 1220 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1221 | |
1222 | rt_drop(rt); | |
b23dd4fe | 1223 | if (skb) |
d8d1f30b | 1224 | skb_dst_set(skb, &rth->dst); |
b23dd4fe | 1225 | return rth; |
1da177e4 LT |
1226 | } |
1227 | ||
d8d1f30b | 1228 | if (!atomic_read(&rth->dst.__refcnt)) { |
1da177e4 LT |
1229 | u32 score = rt_score(rth); |
1230 | ||
1231 | if (score <= min_score) { | |
1232 | cand = rth; | |
1233 | candp = rthp; | |
1234 | min_score = score; | |
1235 | } | |
1236 | } | |
1237 | ||
1238 | chain_length++; | |
1239 | ||
d8d1f30b | 1240 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1241 | } |
1242 | ||
1243 | if (cand) { | |
1244 | /* ip_rt_gc_elasticity used to be average length of chain | |
1245 | * length, when exceeded gc becomes really aggressive. | |
1246 | * | |
1247 | * The second limit is less certain. At the moment it allows | |
1248 | * only 2 entries per bucket. We will see. | |
1249 | */ | |
1250 | if (chain_length > ip_rt_gc_elasticity) { | |
d8d1f30b | 1251 | *candp = cand->dst.rt_next; |
1da177e4 LT |
1252 | rt_free(cand); |
1253 | } | |
1080d709 | 1254 | } else { |
98376387 ED |
1255 | if (chain_length > rt_chain_length_max && |
1256 | slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) { | |
d8d1f30b | 1257 | struct net *net = dev_net(rt->dst.dev); |
1080d709 | 1258 | int num = ++net->ipv4.current_rt_cache_rebuild_count; |
b35ecb5d | 1259 | if (!rt_caching(net)) { |
058bd4d2 | 1260 | pr_warn("%s: %d rebuilds is over limit, route caching disabled\n", |
d8d1f30b | 1261 | rt->dst.dev->name, num); |
1080d709 | 1262 | } |
b35ecb5d | 1263 | rt_emergency_hash_rebuild(net); |
6a2bad70 PE |
1264 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1265 | ||
5e2b61f7 | 1266 | hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
6a2bad70 PE |
1267 | ifindex, rt_genid(net)); |
1268 | goto restart; | |
1080d709 | 1269 | } |
1da177e4 LT |
1270 | } |
1271 | ||
1272 | /* Try to bind route to arp only if it is output | |
1273 | route or unicast forwarding path. | |
1274 | */ | |
c7537967 | 1275 | if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) { |
3769cffb | 1276 | int err = rt_bind_neighbour(rt); |
1da177e4 | 1277 | if (err) { |
22c047cc | 1278 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1279 | |
1280 | if (err != -ENOBUFS) { | |
1281 | rt_drop(rt); | |
b23dd4fe | 1282 | return ERR_PTR(err); |
1da177e4 LT |
1283 | } |
1284 | ||
1285 | /* Neighbour tables are full and nothing | |
1286 | can be released. Try to shrink route cache, | |
1287 | it is most likely it holds some neighbour records. | |
1288 | */ | |
1289 | if (attempts-- > 0) { | |
1290 | int saved_elasticity = ip_rt_gc_elasticity; | |
1291 | int saved_int = ip_rt_gc_min_interval; | |
1292 | ip_rt_gc_elasticity = 1; | |
1293 | ip_rt_gc_min_interval = 0; | |
569d3645 | 1294 | rt_garbage_collect(&ipv4_dst_ops); |
1da177e4 LT |
1295 | ip_rt_gc_min_interval = saved_int; |
1296 | ip_rt_gc_elasticity = saved_elasticity; | |
1297 | goto restart; | |
1298 | } | |
1299 | ||
1300 | if (net_ratelimit()) | |
058bd4d2 | 1301 | pr_warn("ipv4: Neighbour table overflow\n"); |
1da177e4 | 1302 | rt_drop(rt); |
b23dd4fe | 1303 | return ERR_PTR(-ENOBUFS); |
1da177e4 LT |
1304 | } |
1305 | } | |
1306 | ||
d8d1f30b | 1307 | rt->dst.rt_next = rt_hash_table[hash].chain; |
1080d709 | 1308 | |
00269b54 ED |
1309 | /* |
1310 | * Since lookup is lockfree, we must make sure | |
25985edc | 1311 | * previous writes to rt are committed to memory |
00269b54 ED |
1312 | * before making rt visible to other CPUS. |
1313 | */ | |
1ddbcb00 | 1314 | rcu_assign_pointer(rt_hash_table[hash].chain, rt); |
1080d709 | 1315 | |
22c047cc | 1316 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
73e42897 | 1317 | |
b6280b47 | 1318 | skip_hashing: |
b23dd4fe | 1319 | if (skb) |
d8d1f30b | 1320 | skb_dst_set(skb, &rt->dst); |
b23dd4fe | 1321 | return rt; |
1da177e4 LT |
1322 | } |
1323 | ||
6431cbc2 DM |
1324 | static atomic_t __rt_peer_genid = ATOMIC_INIT(0); |
1325 | ||
1326 | static u32 rt_peer_genid(void) | |
1327 | { | |
1328 | return atomic_read(&__rt_peer_genid); | |
1329 | } | |
1330 | ||
a48eff12 | 1331 | void rt_bind_peer(struct rtable *rt, __be32 daddr, int create) |
1da177e4 | 1332 | { |
1da177e4 LT |
1333 | struct inet_peer *peer; |
1334 | ||
a48eff12 | 1335 | peer = inet_getpeer_v4(daddr, create); |
1da177e4 | 1336 | |
49e8ab03 | 1337 | if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL) |
1da177e4 | 1338 | inet_putpeer(peer); |
6431cbc2 DM |
1339 | else |
1340 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 LT |
1341 | } |
1342 | ||
1343 | /* | |
1344 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
1345 | * we still can generate some output. | |
1346 | * Random ID selection looks a bit dangerous because we have no chances to | |
1347 | * select ID being unique in a reasonable period of time. | |
1348 | * But broken packet identifier may be better than no packet at all. | |
1349 | */ | |
1350 | static void ip_select_fb_ident(struct iphdr *iph) | |
1351 | { | |
1352 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
1353 | static u32 ip_fallback_id; | |
1354 | u32 salt; | |
1355 | ||
1356 | spin_lock_bh(&ip_fb_id_lock); | |
e448515c | 1357 | salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr); |
1da177e4 LT |
1358 | iph->id = htons(salt & 0xFFFF); |
1359 | ip_fallback_id = salt; | |
1360 | spin_unlock_bh(&ip_fb_id_lock); | |
1361 | } | |
1362 | ||
1363 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
1364 | { | |
1365 | struct rtable *rt = (struct rtable *) dst; | |
1366 | ||
e688a604 | 1367 | if (rt && !(rt->dst.flags & DST_NOPEER)) { |
1da177e4 | 1368 | if (rt->peer == NULL) |
a48eff12 | 1369 | rt_bind_peer(rt, rt->rt_dst, 1); |
1da177e4 LT |
1370 | |
1371 | /* If peer is attached to destination, it is never detached, | |
1372 | so that we need not to grab a lock to dereference it. | |
1373 | */ | |
1374 | if (rt->peer) { | |
1375 | iph->id = htons(inet_getid(rt->peer, more)); | |
1376 | return; | |
1377 | } | |
e688a604 | 1378 | } else if (!rt) |
e905a9ed | 1379 | printk(KERN_DEBUG "rt_bind_peer(0) @%p\n", |
9c2b3328 | 1380 | __builtin_return_address(0)); |
1da177e4 LT |
1381 | |
1382 | ip_select_fb_ident(iph); | |
1383 | } | |
4bc2f18b | 1384 | EXPORT_SYMBOL(__ip_select_ident); |
1da177e4 LT |
1385 | |
1386 | static void rt_del(unsigned hash, struct rtable *rt) | |
1387 | { | |
1c31720a ED |
1388 | struct rtable __rcu **rthp; |
1389 | struct rtable *aux; | |
1da177e4 | 1390 | |
29e75252 | 1391 | rthp = &rt_hash_table[hash].chain; |
22c047cc | 1392 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1da177e4 | 1393 | ip_rt_put(rt); |
1c31720a ED |
1394 | while ((aux = rcu_dereference_protected(*rthp, |
1395 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1396 | if (aux == rt || rt_is_expired(aux)) { |
d8d1f30b | 1397 | *rthp = aux->dst.rt_next; |
29e75252 ED |
1398 | rt_free(aux); |
1399 | continue; | |
1da177e4 | 1400 | } |
d8d1f30b | 1401 | rthp = &aux->dst.rt_next; |
29e75252 | 1402 | } |
22c047cc | 1403 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1404 | } |
1405 | ||
de398fb8 | 1406 | static void check_peer_redir(struct dst_entry *dst, struct inet_peer *peer) |
9cc20b26 ED |
1407 | { |
1408 | struct rtable *rt = (struct rtable *) dst; | |
1409 | __be32 orig_gw = rt->rt_gateway; | |
1410 | struct neighbour *n, *old_n; | |
1411 | ||
1412 | dst_confirm(&rt->dst); | |
1413 | ||
1414 | rt->rt_gateway = peer->redirect_learned.a4; | |
1415 | ||
1416 | n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway); | |
de398fb8 DM |
1417 | if (IS_ERR(n)) { |
1418 | rt->rt_gateway = orig_gw; | |
1419 | return; | |
1420 | } | |
9cc20b26 ED |
1421 | old_n = xchg(&rt->dst._neighbour, n); |
1422 | if (old_n) | |
1423 | neigh_release(old_n); | |
de398fb8 DM |
1424 | if (!(n->nud_state & NUD_VALID)) { |
1425 | neigh_event_send(n, NULL); | |
9cc20b26 ED |
1426 | } else { |
1427 | rt->rt_flags |= RTCF_REDIRECTED; | |
1428 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); | |
1429 | } | |
9cc20b26 ED |
1430 | } |
1431 | ||
ed7865a4 | 1432 | /* called in rcu_read_lock() section */ |
f7655229 AV |
1433 | void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, |
1434 | __be32 saddr, struct net_device *dev) | |
1da177e4 | 1435 | { |
7cc9150e | 1436 | int s, i; |
ed7865a4 | 1437 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
7cc9150e FL |
1438 | __be32 skeys[2] = { saddr, 0 }; |
1439 | int ikeys[2] = { dev->ifindex, 0 }; | |
f39925db | 1440 | struct inet_peer *peer; |
317805b8 | 1441 | struct net *net; |
1da177e4 | 1442 | |
1da177e4 LT |
1443 | if (!in_dev) |
1444 | return; | |
1445 | ||
c346dca1 | 1446 | net = dev_net(dev); |
9d4fb27d JP |
1447 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || |
1448 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
1449 | ipv4_is_zeronet(new_gw)) | |
1da177e4 LT |
1450 | goto reject_redirect; |
1451 | ||
1452 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
1453 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
1454 | goto reject_redirect; | |
1455 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
1456 | goto reject_redirect; | |
1457 | } else { | |
317805b8 | 1458 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) |
1da177e4 LT |
1459 | goto reject_redirect; |
1460 | } | |
1461 | ||
7cc9150e FL |
1462 | for (s = 0; s < 2; s++) { |
1463 | for (i = 0; i < 2; i++) { | |
9cc20b26 ED |
1464 | unsigned int hash; |
1465 | struct rtable __rcu **rthp; | |
1466 | struct rtable *rt; | |
1467 | ||
1468 | hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net)); | |
1469 | ||
1470 | rthp = &rt_hash_table[hash].chain; | |
1471 | ||
1472 | while ((rt = rcu_dereference(*rthp)) != NULL) { | |
1473 | rthp = &rt->dst.rt_next; | |
1474 | ||
1475 | if (rt->rt_key_dst != daddr || | |
1476 | rt->rt_key_src != skeys[s] || | |
1477 | rt->rt_oif != ikeys[i] || | |
1478 | rt_is_input_route(rt) || | |
1479 | rt_is_expired(rt) || | |
1480 | !net_eq(dev_net(rt->dst.dev), net) || | |
1481 | rt->dst.error || | |
1482 | rt->dst.dev != dev || | |
1483 | rt->rt_gateway != old_gw) | |
1484 | continue; | |
e905a9ed | 1485 | |
9cc20b26 ED |
1486 | if (!rt->peer) |
1487 | rt_bind_peer(rt, rt->rt_dst, 1); | |
1da177e4 | 1488 | |
9cc20b26 ED |
1489 | peer = rt->peer; |
1490 | if (peer) { | |
ac3f48de | 1491 | if (peer->redirect_learned.a4 != new_gw) { |
9cc20b26 ED |
1492 | peer->redirect_learned.a4 = new_gw; |
1493 | atomic_inc(&__rt_peer_genid); | |
1494 | } | |
1495 | check_peer_redir(&rt->dst, peer); | |
1496 | } | |
7cc9150e | 1497 | } |
7cc9150e | 1498 | } |
1da177e4 | 1499 | } |
1da177e4 LT |
1500 | return; |
1501 | ||
1502 | reject_redirect: | |
1503 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1504 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
058bd4d2 | 1505 | pr_info("Redirect from %pI4 on %s about %pI4 ignored\n" |
673d57e7 | 1506 | " Advised path = %pI4 -> %pI4\n", |
058bd4d2 JP |
1507 | &old_gw, dev->name, &new_gw, |
1508 | &saddr, &daddr); | |
1da177e4 | 1509 | #endif |
ed7865a4 | 1510 | ; |
1da177e4 LT |
1511 | } |
1512 | ||
fe6fe792 ED |
1513 | static bool peer_pmtu_expired(struct inet_peer *peer) |
1514 | { | |
1515 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1516 | ||
1517 | return orig && | |
1518 | time_after_eq(jiffies, orig) && | |
1519 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1520 | } | |
1521 | ||
1522 | static bool peer_pmtu_cleaned(struct inet_peer *peer) | |
1523 | { | |
1524 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1525 | ||
1526 | return orig && | |
1527 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1528 | } | |
1529 | ||
1da177e4 LT |
1530 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) |
1531 | { | |
ee6b9673 | 1532 | struct rtable *rt = (struct rtable *)dst; |
1da177e4 LT |
1533 | struct dst_entry *ret = dst; |
1534 | ||
1535 | if (rt) { | |
d11a4dc1 | 1536 | if (dst->obsolete > 0) { |
1da177e4 LT |
1537 | ip_rt_put(rt); |
1538 | ret = NULL; | |
2c8cec5c | 1539 | } else if (rt->rt_flags & RTCF_REDIRECTED) { |
5e2b61f7 DM |
1540 | unsigned hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
1541 | rt->rt_oif, | |
e84f84f2 | 1542 | rt_genid(dev_net(dst->dev))); |
1da177e4 LT |
1543 | rt_del(hash, rt); |
1544 | ret = NULL; | |
fe6fe792 ED |
1545 | } else if (rt->peer && peer_pmtu_expired(rt->peer)) { |
1546 | dst_metric_set(dst, RTAX_MTU, rt->peer->pmtu_orig); | |
1da177e4 LT |
1547 | } |
1548 | } | |
1549 | return ret; | |
1550 | } | |
1551 | ||
1552 | /* | |
1553 | * Algorithm: | |
1554 | * 1. The first ip_rt_redirect_number redirects are sent | |
1555 | * with exponential backoff, then we stop sending them at all, | |
1556 | * assuming that the host ignores our redirects. | |
1557 | * 2. If we did not see packets requiring redirects | |
1558 | * during ip_rt_redirect_silence, we assume that the host | |
1559 | * forgot redirected route and start to send redirects again. | |
1560 | * | |
1561 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
1562 | * in icmp.c. | |
1563 | * | |
1564 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
1565 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
1566 | */ | |
1567 | ||
1568 | void ip_rt_send_redirect(struct sk_buff *skb) | |
1569 | { | |
511c3f92 | 1570 | struct rtable *rt = skb_rtable(skb); |
30038fc6 | 1571 | struct in_device *in_dev; |
92d86829 | 1572 | struct inet_peer *peer; |
30038fc6 | 1573 | int log_martians; |
1da177e4 | 1574 | |
30038fc6 | 1575 | rcu_read_lock(); |
d8d1f30b | 1576 | in_dev = __in_dev_get_rcu(rt->dst.dev); |
30038fc6 ED |
1577 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { |
1578 | rcu_read_unlock(); | |
1da177e4 | 1579 | return; |
30038fc6 ED |
1580 | } |
1581 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
1582 | rcu_read_unlock(); | |
1da177e4 | 1583 | |
92d86829 | 1584 | if (!rt->peer) |
a48eff12 | 1585 | rt_bind_peer(rt, rt->rt_dst, 1); |
92d86829 DM |
1586 | peer = rt->peer; |
1587 | if (!peer) { | |
1588 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
1589 | return; | |
1590 | } | |
1591 | ||
1da177e4 LT |
1592 | /* No redirected packets during ip_rt_redirect_silence; |
1593 | * reset the algorithm. | |
1594 | */ | |
92d86829 DM |
1595 | if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) |
1596 | peer->rate_tokens = 0; | |
1da177e4 LT |
1597 | |
1598 | /* Too many ignored redirects; do not send anything | |
d8d1f30b | 1599 | * set dst.rate_last to the last seen redirected packet. |
1da177e4 | 1600 | */ |
92d86829 DM |
1601 | if (peer->rate_tokens >= ip_rt_redirect_number) { |
1602 | peer->rate_last = jiffies; | |
30038fc6 | 1603 | return; |
1da177e4 LT |
1604 | } |
1605 | ||
1606 | /* Check for load limit; set rate_last to the latest sent | |
1607 | * redirect. | |
1608 | */ | |
92d86829 | 1609 | if (peer->rate_tokens == 0 || |
14fb8a76 | 1610 | time_after(jiffies, |
92d86829 DM |
1611 | (peer->rate_last + |
1612 | (ip_rt_redirect_load << peer->rate_tokens)))) { | |
1da177e4 | 1613 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); |
92d86829 DM |
1614 | peer->rate_last = jiffies; |
1615 | ++peer->rate_tokens; | |
1da177e4 | 1616 | #ifdef CONFIG_IP_ROUTE_VERBOSE |
30038fc6 | 1617 | if (log_martians && |
92d86829 | 1618 | peer->rate_tokens == ip_rt_redirect_number && |
1da177e4 | 1619 | net_ratelimit()) |
058bd4d2 JP |
1620 | pr_warn("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", |
1621 | &ip_hdr(skb)->saddr, rt->rt_iif, | |
673d57e7 | 1622 | &rt->rt_dst, &rt->rt_gateway); |
1da177e4 LT |
1623 | #endif |
1624 | } | |
1da177e4 LT |
1625 | } |
1626 | ||
1627 | static int ip_error(struct sk_buff *skb) | |
1628 | { | |
511c3f92 | 1629 | struct rtable *rt = skb_rtable(skb); |
92d86829 | 1630 | struct inet_peer *peer; |
1da177e4 | 1631 | unsigned long now; |
92d86829 | 1632 | bool send; |
1da177e4 LT |
1633 | int code; |
1634 | ||
d8d1f30b | 1635 | switch (rt->dst.error) { |
4500ebf8 JP |
1636 | case EINVAL: |
1637 | default: | |
1638 | goto out; | |
1639 | case EHOSTUNREACH: | |
1640 | code = ICMP_HOST_UNREACH; | |
1641 | break; | |
1642 | case ENETUNREACH: | |
1643 | code = ICMP_NET_UNREACH; | |
1644 | IP_INC_STATS_BH(dev_net(rt->dst.dev), | |
1645 | IPSTATS_MIB_INNOROUTES); | |
1646 | break; | |
1647 | case EACCES: | |
1648 | code = ICMP_PKT_FILTERED; | |
1649 | break; | |
1da177e4 LT |
1650 | } |
1651 | ||
92d86829 | 1652 | if (!rt->peer) |
a48eff12 | 1653 | rt_bind_peer(rt, rt->rt_dst, 1); |
92d86829 DM |
1654 | peer = rt->peer; |
1655 | ||
1656 | send = true; | |
1657 | if (peer) { | |
1658 | now = jiffies; | |
1659 | peer->rate_tokens += now - peer->rate_last; | |
1660 | if (peer->rate_tokens > ip_rt_error_burst) | |
1661 | peer->rate_tokens = ip_rt_error_burst; | |
1662 | peer->rate_last = now; | |
1663 | if (peer->rate_tokens >= ip_rt_error_cost) | |
1664 | peer->rate_tokens -= ip_rt_error_cost; | |
1665 | else | |
1666 | send = false; | |
1da177e4 | 1667 | } |
92d86829 DM |
1668 | if (send) |
1669 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1da177e4 LT |
1670 | |
1671 | out: kfree_skb(skb); | |
1672 | return 0; | |
e905a9ed | 1673 | } |
1da177e4 LT |
1674 | |
1675 | /* | |
1676 | * The last two values are not from the RFC but | |
1677 | * are needed for AMPRnet AX.25 paths. | |
1678 | */ | |
1679 | ||
9b5b5cff | 1680 | static const unsigned short mtu_plateau[] = |
1da177e4 LT |
1681 | {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 }; |
1682 | ||
5969f71d | 1683 | static inline unsigned short guess_mtu(unsigned short old_mtu) |
1da177e4 LT |
1684 | { |
1685 | int i; | |
e905a9ed | 1686 | |
1da177e4 LT |
1687 | for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++) |
1688 | if (old_mtu > mtu_plateau[i]) | |
1689 | return mtu_plateau[i]; | |
1690 | return 68; | |
1691 | } | |
1692 | ||
b71d1d42 | 1693 | unsigned short ip_rt_frag_needed(struct net *net, const struct iphdr *iph, |
0010e465 TT |
1694 | unsigned short new_mtu, |
1695 | struct net_device *dev) | |
1da177e4 | 1696 | { |
1da177e4 | 1697 | unsigned short old_mtu = ntohs(iph->tot_len); |
1da177e4 | 1698 | unsigned short est_mtu = 0; |
2c8cec5c | 1699 | struct inet_peer *peer; |
1da177e4 | 1700 | |
2c8cec5c DM |
1701 | peer = inet_getpeer_v4(iph->daddr, 1); |
1702 | if (peer) { | |
1703 | unsigned short mtu = new_mtu; | |
1da177e4 | 1704 | |
2c8cec5c DM |
1705 | if (new_mtu < 68 || new_mtu >= old_mtu) { |
1706 | /* BSD 4.2 derived systems incorrectly adjust | |
1707 | * tot_len by the IP header length, and report | |
1708 | * a zero MTU in the ICMP message. | |
1709 | */ | |
1710 | if (mtu == 0 && | |
1711 | old_mtu >= 68 + (iph->ihl << 2)) | |
1712 | old_mtu -= iph->ihl << 2; | |
1713 | mtu = guess_mtu(old_mtu); | |
1714 | } | |
0010e465 | 1715 | |
2c8cec5c DM |
1716 | if (mtu < ip_rt_min_pmtu) |
1717 | mtu = ip_rt_min_pmtu; | |
1718 | if (!peer->pmtu_expires || mtu < peer->pmtu_learned) { | |
46af3180 HS |
1719 | unsigned long pmtu_expires; |
1720 | ||
1721 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1722 | if (!pmtu_expires) | |
1723 | pmtu_expires = 1UL; | |
1724 | ||
2c8cec5c DM |
1725 | est_mtu = mtu; |
1726 | peer->pmtu_learned = mtu; | |
46af3180 | 1727 | peer->pmtu_expires = pmtu_expires; |
59445b6b | 1728 | atomic_inc(&__rt_peer_genid); |
2c8cec5c | 1729 | } |
1da177e4 | 1730 | |
2c8cec5c | 1731 | inet_putpeer(peer); |
1da177e4 LT |
1732 | } |
1733 | return est_mtu ? : new_mtu; | |
1734 | } | |
1735 | ||
2c8cec5c DM |
1736 | static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer) |
1737 | { | |
fe6fe792 | 1738 | unsigned long expires = ACCESS_ONCE(peer->pmtu_expires); |
2c8cec5c | 1739 | |
fe6fe792 ED |
1740 | if (!expires) |
1741 | return; | |
46af3180 | 1742 | if (time_before(jiffies, expires)) { |
2c8cec5c DM |
1743 | u32 orig_dst_mtu = dst_mtu(dst); |
1744 | if (peer->pmtu_learned < orig_dst_mtu) { | |
1745 | if (!peer->pmtu_orig) | |
1746 | peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU); | |
1747 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned); | |
1748 | } | |
1749 | } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires) | |
1750 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); | |
1751 | } | |
1752 | ||
1da177e4 LT |
1753 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) |
1754 | { | |
2c8cec5c DM |
1755 | struct rtable *rt = (struct rtable *) dst; |
1756 | struct inet_peer *peer; | |
1757 | ||
1758 | dst_confirm(dst); | |
1759 | ||
1760 | if (!rt->peer) | |
a48eff12 | 1761 | rt_bind_peer(rt, rt->rt_dst, 1); |
2c8cec5c DM |
1762 | peer = rt->peer; |
1763 | if (peer) { | |
fe6fe792 ED |
1764 | unsigned long pmtu_expires = ACCESS_ONCE(peer->pmtu_expires); |
1765 | ||
2c8cec5c | 1766 | if (mtu < ip_rt_min_pmtu) |
1da177e4 | 1767 | mtu = ip_rt_min_pmtu; |
fe6fe792 | 1768 | if (!pmtu_expires || mtu < peer->pmtu_learned) { |
46af3180 HS |
1769 | |
1770 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1771 | if (!pmtu_expires) | |
1772 | pmtu_expires = 1UL; | |
1773 | ||
2c8cec5c | 1774 | peer->pmtu_learned = mtu; |
46af3180 | 1775 | peer->pmtu_expires = pmtu_expires; |
2c8cec5c DM |
1776 | |
1777 | atomic_inc(&__rt_peer_genid); | |
1778 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 | 1779 | } |
46af3180 | 1780 | check_peer_pmtu(dst, peer); |
1da177e4 LT |
1781 | } |
1782 | } | |
1783 | ||
f39925db | 1784 | |
de398fb8 | 1785 | static void ipv4_validate_peer(struct rtable *rt) |
1da177e4 | 1786 | { |
6431cbc2 | 1787 | if (rt->rt_peer_genid != rt_peer_genid()) { |
2c8cec5c DM |
1788 | struct inet_peer *peer; |
1789 | ||
6431cbc2 | 1790 | if (!rt->peer) |
a48eff12 | 1791 | rt_bind_peer(rt, rt->rt_dst, 0); |
6431cbc2 | 1792 | |
2c8cec5c | 1793 | peer = rt->peer; |
fe6fe792 | 1794 | if (peer) { |
efbc368d | 1795 | check_peer_pmtu(&rt->dst, peer); |
2c8cec5c | 1796 | |
fe6fe792 | 1797 | if (peer->redirect_learned.a4 && |
de398fb8 DM |
1798 | peer->redirect_learned.a4 != rt->rt_gateway) |
1799 | check_peer_redir(&rt->dst, peer); | |
f39925db DM |
1800 | } |
1801 | ||
6431cbc2 DM |
1802 | rt->rt_peer_genid = rt_peer_genid(); |
1803 | } | |
efbc368d DM |
1804 | } |
1805 | ||
1806 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) | |
1807 | { | |
1808 | struct rtable *rt = (struct rtable *) dst; | |
1809 | ||
1810 | if (rt_is_expired(rt)) | |
1811 | return NULL; | |
de398fb8 | 1812 | ipv4_validate_peer(rt); |
d11a4dc1 | 1813 | return dst; |
1da177e4 LT |
1814 | } |
1815 | ||
1816 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1817 | { | |
1818 | struct rtable *rt = (struct rtable *) dst; | |
1819 | struct inet_peer *peer = rt->peer; | |
1da177e4 | 1820 | |
62fa8a84 DM |
1821 | if (rt->fi) { |
1822 | fib_info_put(rt->fi); | |
1823 | rt->fi = NULL; | |
1824 | } | |
1da177e4 LT |
1825 | if (peer) { |
1826 | rt->peer = NULL; | |
1827 | inet_putpeer(peer); | |
1828 | } | |
1da177e4 LT |
1829 | } |
1830 | ||
1da177e4 LT |
1831 | |
1832 | static void ipv4_link_failure(struct sk_buff *skb) | |
1833 | { | |
1834 | struct rtable *rt; | |
1835 | ||
1836 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1837 | ||
511c3f92 | 1838 | rt = skb_rtable(skb); |
fe6fe792 ED |
1839 | if (rt && rt->peer && peer_pmtu_cleaned(rt->peer)) |
1840 | dst_metric_set(&rt->dst, RTAX_MTU, rt->peer->pmtu_orig); | |
1da177e4 LT |
1841 | } |
1842 | ||
1843 | static int ip_rt_bug(struct sk_buff *skb) | |
1844 | { | |
673d57e7 HH |
1845 | printk(KERN_DEBUG "ip_rt_bug: %pI4 -> %pI4, %s\n", |
1846 | &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1da177e4 LT |
1847 | skb->dev ? skb->dev->name : "?"); |
1848 | kfree_skb(skb); | |
c378a9c0 | 1849 | WARN_ON(1); |
1da177e4 LT |
1850 | return 0; |
1851 | } | |
1852 | ||
1853 | /* | |
1854 | We do not cache source address of outgoing interface, | |
1855 | because it is used only by IP RR, TS and SRR options, | |
1856 | so that it out of fast path. | |
1857 | ||
1858 | BTW remember: "addr" is allowed to be not aligned | |
1859 | in IP options! | |
1860 | */ | |
1861 | ||
8e36360a | 1862 | void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) |
1da177e4 | 1863 | { |
a61ced5d | 1864 | __be32 src; |
1da177e4 | 1865 | |
c7537967 | 1866 | if (rt_is_output_route(rt)) |
c5be24ff | 1867 | src = ip_hdr(skb)->saddr; |
ebc0ffae | 1868 | else { |
8e36360a DM |
1869 | struct fib_result res; |
1870 | struct flowi4 fl4; | |
1871 | struct iphdr *iph; | |
1872 | ||
1873 | iph = ip_hdr(skb); | |
1874 | ||
1875 | memset(&fl4, 0, sizeof(fl4)); | |
1876 | fl4.daddr = iph->daddr; | |
1877 | fl4.saddr = iph->saddr; | |
b0fe4a31 | 1878 | fl4.flowi4_tos = RT_TOS(iph->tos); |
8e36360a DM |
1879 | fl4.flowi4_oif = rt->dst.dev->ifindex; |
1880 | fl4.flowi4_iif = skb->dev->ifindex; | |
1881 | fl4.flowi4_mark = skb->mark; | |
5e2b61f7 | 1882 | |
ebc0ffae | 1883 | rcu_read_lock(); |
68a5e3dd | 1884 | if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0) |
436c3b66 | 1885 | src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); |
ebc0ffae ED |
1886 | else |
1887 | src = inet_select_addr(rt->dst.dev, rt->rt_gateway, | |
1da177e4 | 1888 | RT_SCOPE_UNIVERSE); |
ebc0ffae ED |
1889 | rcu_read_unlock(); |
1890 | } | |
1da177e4 LT |
1891 | memcpy(addr, &src, 4); |
1892 | } | |
1893 | ||
c7066f70 | 1894 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1895 | static void set_class_tag(struct rtable *rt, u32 tag) |
1896 | { | |
d8d1f30b CG |
1897 | if (!(rt->dst.tclassid & 0xFFFF)) |
1898 | rt->dst.tclassid |= tag & 0xFFFF; | |
1899 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1900 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1da177e4 LT |
1901 | } |
1902 | #endif | |
1903 | ||
0dbaee3b DM |
1904 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst) |
1905 | { | |
1906 | unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS); | |
1907 | ||
1908 | if (advmss == 0) { | |
1909 | advmss = max_t(unsigned int, dst->dev->mtu - 40, | |
1910 | ip_rt_min_advmss); | |
1911 | if (advmss > 65535 - 40) | |
1912 | advmss = 65535 - 40; | |
1913 | } | |
1914 | return advmss; | |
1915 | } | |
1916 | ||
ebb762f2 | 1917 | static unsigned int ipv4_mtu(const struct dst_entry *dst) |
d33e4553 | 1918 | { |
261663b0 | 1919 | const struct rtable *rt = (const struct rtable *) dst; |
618f9bc7 SK |
1920 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
1921 | ||
261663b0 | 1922 | if (mtu && rt_is_output_route(rt)) |
618f9bc7 SK |
1923 | return mtu; |
1924 | ||
1925 | mtu = dst->dev->mtu; | |
d33e4553 DM |
1926 | |
1927 | if (unlikely(dst_metric_locked(dst, RTAX_MTU))) { | |
d33e4553 DM |
1928 | |
1929 | if (rt->rt_gateway != rt->rt_dst && mtu > 576) | |
1930 | mtu = 576; | |
1931 | } | |
1932 | ||
1933 | if (mtu > IP_MAX_MTU) | |
1934 | mtu = IP_MAX_MTU; | |
1935 | ||
1936 | return mtu; | |
1937 | } | |
1938 | ||
813b3b5d | 1939 | static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1940 | struct fib_info *fi) |
a4daad6b | 1941 | { |
0131ba45 DM |
1942 | struct inet_peer *peer; |
1943 | int create = 0; | |
a4daad6b | 1944 | |
0131ba45 DM |
1945 | /* If a peer entry exists for this destination, we must hook |
1946 | * it up in order to get at cached metrics. | |
1947 | */ | |
813b3b5d | 1948 | if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS)) |
0131ba45 DM |
1949 | create = 1; |
1950 | ||
3c0afdca | 1951 | rt->peer = peer = inet_getpeer_v4(rt->rt_dst, create); |
0131ba45 | 1952 | if (peer) { |
3c0afdca | 1953 | rt->rt_peer_genid = rt_peer_genid(); |
a4daad6b DM |
1954 | if (inet_metrics_new(peer)) |
1955 | memcpy(peer->metrics, fi->fib_metrics, | |
1956 | sizeof(u32) * RTAX_MAX); | |
1957 | dst_init_metrics(&rt->dst, peer->metrics, false); | |
2c8cec5c | 1958 | |
fe6fe792 | 1959 | check_peer_pmtu(&rt->dst, peer); |
ac3f48de | 1960 | |
f39925db DM |
1961 | if (peer->redirect_learned.a4 && |
1962 | peer->redirect_learned.a4 != rt->rt_gateway) { | |
1963 | rt->rt_gateway = peer->redirect_learned.a4; | |
1964 | rt->rt_flags |= RTCF_REDIRECTED; | |
1965 | } | |
0131ba45 DM |
1966 | } else { |
1967 | if (fi->fib_metrics != (u32 *) dst_default_metrics) { | |
1968 | rt->fi = fi; | |
1969 | atomic_inc(&fi->fib_clntref); | |
1970 | } | |
1971 | dst_init_metrics(&rt->dst, fi->fib_metrics, true); | |
a4daad6b DM |
1972 | } |
1973 | } | |
1974 | ||
813b3b5d | 1975 | static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1976 | const struct fib_result *res, |
982721f3 | 1977 | struct fib_info *fi, u16 type, u32 itag) |
1da177e4 | 1978 | { |
defb3519 | 1979 | struct dst_entry *dst = &rt->dst; |
1da177e4 LT |
1980 | |
1981 | if (fi) { | |
1982 | if (FIB_RES_GW(*res) && | |
1983 | FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
1984 | rt->rt_gateway = FIB_RES_GW(*res); | |
813b3b5d | 1985 | rt_init_metrics(rt, fl4, fi); |
c7066f70 | 1986 | #ifdef CONFIG_IP_ROUTE_CLASSID |
defb3519 | 1987 | dst->tclassid = FIB_RES_NH(*res).nh_tclassid; |
1da177e4 | 1988 | #endif |
d33e4553 | 1989 | } |
defb3519 | 1990 | |
defb3519 DM |
1991 | if (dst_mtu(dst) > IP_MAX_MTU) |
1992 | dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU); | |
0dbaee3b | 1993 | if (dst_metric_raw(dst, RTAX_ADVMSS) > 65535 - 40) |
defb3519 | 1994 | dst_metric_set(dst, RTAX_ADVMSS, 65535 - 40); |
1da177e4 | 1995 | |
c7066f70 | 1996 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1997 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
1998 | set_class_tag(rt, fib_rules_tclass(res)); | |
1999 | #endif | |
2000 | set_class_tag(rt, itag); | |
2001 | #endif | |
1da177e4 LT |
2002 | } |
2003 | ||
5c1e6aa3 DM |
2004 | static struct rtable *rt_dst_alloc(struct net_device *dev, |
2005 | bool nopolicy, bool noxfrm) | |
0c4dcd58 | 2006 | { |
5c1e6aa3 DM |
2007 | return dst_alloc(&ipv4_dst_ops, dev, 1, -1, |
2008 | DST_HOST | | |
2009 | (nopolicy ? DST_NOPOLICY : 0) | | |
2010 | (noxfrm ? DST_NOXFRM : 0)); | |
0c4dcd58 DM |
2011 | } |
2012 | ||
96d36220 | 2013 | /* called in rcu_read_lock() section */ |
9e12bb22 | 2014 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
2015 | u8 tos, struct net_device *dev, int our) |
2016 | { | |
96d36220 | 2017 | unsigned int hash; |
1da177e4 | 2018 | struct rtable *rth; |
a61ced5d | 2019 | __be32 spec_dst; |
96d36220 | 2020 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2021 | u32 itag = 0; |
b5f7e755 | 2022 | int err; |
1da177e4 LT |
2023 | |
2024 | /* Primary sanity checks. */ | |
2025 | ||
2026 | if (in_dev == NULL) | |
2027 | return -EINVAL; | |
2028 | ||
1e637c74 | 2029 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
f97c1e0c | 2030 | ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP)) |
1da177e4 LT |
2031 | goto e_inval; |
2032 | ||
f97c1e0c JP |
2033 | if (ipv4_is_zeronet(saddr)) { |
2034 | if (!ipv4_is_local_multicast(daddr)) | |
1da177e4 LT |
2035 | goto e_inval; |
2036 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
b5f7e755 | 2037 | } else { |
5c04c819 MS |
2038 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, &spec_dst, |
2039 | &itag); | |
b5f7e755 ED |
2040 | if (err < 0) |
2041 | goto e_err; | |
2042 | } | |
5c1e6aa3 DM |
2043 | rth = rt_dst_alloc(init_net.loopback_dev, |
2044 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); | |
1da177e4 LT |
2045 | if (!rth) |
2046 | goto e_nobufs; | |
2047 | ||
cf911662 DM |
2048 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2049 | rth->dst.tclassid = itag; | |
2050 | #endif | |
d8d1f30b | 2051 | rth->dst.output = ip_rt_bug; |
1da177e4 | 2052 | |
5e2b61f7 | 2053 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2054 | rth->rt_key_src = saddr; |
cf911662 DM |
2055 | rth->rt_genid = rt_genid(dev_net(dev)); |
2056 | rth->rt_flags = RTCF_MULTICAST; | |
2057 | rth->rt_type = RTN_MULTICAST; | |
475949d8 | 2058 | rth->rt_key_tos = tos; |
cf911662 | 2059 | rth->rt_dst = daddr; |
1da177e4 | 2060 | rth->rt_src = saddr; |
1b86a58f | 2061 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2062 | rth->rt_iif = dev->ifindex; |
5e2b61f7 | 2063 | rth->rt_oif = 0; |
cf911662 | 2064 | rth->rt_mark = skb->mark; |
1da177e4 LT |
2065 | rth->rt_gateway = daddr; |
2066 | rth->rt_spec_dst= spec_dst; | |
cf911662 DM |
2067 | rth->rt_peer_genid = 0; |
2068 | rth->peer = NULL; | |
2069 | rth->fi = NULL; | |
1da177e4 | 2070 | if (our) { |
d8d1f30b | 2071 | rth->dst.input= ip_local_deliver; |
1da177e4 LT |
2072 | rth->rt_flags |= RTCF_LOCAL; |
2073 | } | |
2074 | ||
2075 | #ifdef CONFIG_IP_MROUTE | |
f97c1e0c | 2076 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) |
d8d1f30b | 2077 | rth->dst.input = ip_mr_input; |
1da177e4 LT |
2078 | #endif |
2079 | RT_CACHE_STAT_INC(in_slow_mc); | |
2080 | ||
e84f84f2 | 2081 | hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev))); |
b23dd4fe | 2082 | rth = rt_intern_hash(hash, rth, skb, dev->ifindex); |
9aa3c94c | 2083 | return IS_ERR(rth) ? PTR_ERR(rth) : 0; |
1da177e4 LT |
2084 | |
2085 | e_nobufs: | |
1da177e4 | 2086 | return -ENOBUFS; |
1da177e4 | 2087 | e_inval: |
96d36220 | 2088 | return -EINVAL; |
b5f7e755 | 2089 | e_err: |
b5f7e755 | 2090 | return err; |
1da177e4 LT |
2091 | } |
2092 | ||
2093 | ||
2094 | static void ip_handle_martian_source(struct net_device *dev, | |
2095 | struct in_device *in_dev, | |
2096 | struct sk_buff *skb, | |
9e12bb22 AV |
2097 | __be32 daddr, |
2098 | __be32 saddr) | |
1da177e4 LT |
2099 | { |
2100 | RT_CACHE_STAT_INC(in_martian_src); | |
2101 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2102 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
2103 | /* | |
2104 | * RFC1812 recommendation, if source is martian, | |
2105 | * the only hint is MAC header. | |
2106 | */ | |
058bd4d2 | 2107 | pr_warn("martian source %pI4 from %pI4, on dev %s\n", |
673d57e7 | 2108 | &daddr, &saddr, dev->name); |
98e399f8 | 2109 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { |
058bd4d2 JP |
2110 | print_hex_dump(KERN_WARNING, "ll header: ", |
2111 | DUMP_PREFIX_OFFSET, 16, 1, | |
2112 | skb_mac_header(skb), | |
2113 | dev->hard_header_len, true); | |
1da177e4 LT |
2114 | } |
2115 | } | |
2116 | #endif | |
2117 | } | |
2118 | ||
47360228 | 2119 | /* called in rcu_read_lock() section */ |
5969f71d | 2120 | static int __mkroute_input(struct sk_buff *skb, |
982721f3 | 2121 | const struct fib_result *res, |
5969f71d SH |
2122 | struct in_device *in_dev, |
2123 | __be32 daddr, __be32 saddr, u32 tos, | |
2124 | struct rtable **result) | |
1da177e4 | 2125 | { |
1da177e4 LT |
2126 | struct rtable *rth; |
2127 | int err; | |
2128 | struct in_device *out_dev; | |
47360228 | 2129 | unsigned int flags = 0; |
d9c9df8c AV |
2130 | __be32 spec_dst; |
2131 | u32 itag; | |
1da177e4 LT |
2132 | |
2133 | /* get a working reference to the output device */ | |
47360228 | 2134 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); |
1da177e4 LT |
2135 | if (out_dev == NULL) { |
2136 | if (net_ratelimit()) | |
058bd4d2 | 2137 | pr_crit("Bug in ip_route_input_slow(). Please report.\n"); |
1da177e4 LT |
2138 | return -EINVAL; |
2139 | } | |
2140 | ||
2141 | ||
5c04c819 MS |
2142 | err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), |
2143 | in_dev->dev, &spec_dst, &itag); | |
1da177e4 | 2144 | if (err < 0) { |
e905a9ed | 2145 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, |
1da177e4 | 2146 | saddr); |
e905a9ed | 2147 | |
1da177e4 LT |
2148 | goto cleanup; |
2149 | } | |
2150 | ||
2151 | if (err) | |
2152 | flags |= RTCF_DIRECTSRC; | |
2153 | ||
51b77cae | 2154 | if (out_dev == in_dev && err && |
1da177e4 LT |
2155 | (IN_DEV_SHARED_MEDIA(out_dev) || |
2156 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
2157 | flags |= RTCF_DOREDIRECT; | |
2158 | ||
2159 | if (skb->protocol != htons(ETH_P_IP)) { | |
2160 | /* Not IP (i.e. ARP). Do not create route, if it is | |
2161 | * invalid for proxy arp. DNAT routes are always valid. | |
65324144 JDB |
2162 | * |
2163 | * Proxy arp feature have been extended to allow, ARP | |
2164 | * replies back to the same interface, to support | |
2165 | * Private VLAN switch technologies. See arp.c. | |
1da177e4 | 2166 | */ |
65324144 JDB |
2167 | if (out_dev == in_dev && |
2168 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
1da177e4 LT |
2169 | err = -EINVAL; |
2170 | goto cleanup; | |
2171 | } | |
2172 | } | |
2173 | ||
5c1e6aa3 DM |
2174 | rth = rt_dst_alloc(out_dev->dev, |
2175 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2176 | IN_DEV_CONF_GET(out_dev, NOXFRM)); |
1da177e4 LT |
2177 | if (!rth) { |
2178 | err = -ENOBUFS; | |
2179 | goto cleanup; | |
2180 | } | |
2181 | ||
5e2b61f7 | 2182 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2183 | rth->rt_key_src = saddr; |
cf911662 DM |
2184 | rth->rt_genid = rt_genid(dev_net(rth->dst.dev)); |
2185 | rth->rt_flags = flags; | |
2186 | rth->rt_type = res->type; | |
475949d8 | 2187 | rth->rt_key_tos = tos; |
cf911662 | 2188 | rth->rt_dst = daddr; |
1da177e4 | 2189 | rth->rt_src = saddr; |
1b86a58f | 2190 | rth->rt_route_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2191 | rth->rt_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2192 | rth->rt_oif = 0; |
cf911662 DM |
2193 | rth->rt_mark = skb->mark; |
2194 | rth->rt_gateway = daddr; | |
1da177e4 | 2195 | rth->rt_spec_dst= spec_dst; |
cf911662 DM |
2196 | rth->rt_peer_genid = 0; |
2197 | rth->peer = NULL; | |
2198 | rth->fi = NULL; | |
1da177e4 | 2199 | |
d8d1f30b CG |
2200 | rth->dst.input = ip_forward; |
2201 | rth->dst.output = ip_output; | |
1da177e4 | 2202 | |
5e2b61f7 | 2203 | rt_set_nexthop(rth, NULL, res, res->fi, res->type, itag); |
1da177e4 | 2204 | |
1da177e4 LT |
2205 | *result = rth; |
2206 | err = 0; | |
2207 | cleanup: | |
1da177e4 | 2208 | return err; |
e905a9ed | 2209 | } |
1da177e4 | 2210 | |
5969f71d SH |
2211 | static int ip_mkroute_input(struct sk_buff *skb, |
2212 | struct fib_result *res, | |
68a5e3dd | 2213 | const struct flowi4 *fl4, |
5969f71d SH |
2214 | struct in_device *in_dev, |
2215 | __be32 daddr, __be32 saddr, u32 tos) | |
1da177e4 | 2216 | { |
7abaa27c | 2217 | struct rtable* rth = NULL; |
1da177e4 LT |
2218 | int err; |
2219 | unsigned hash; | |
2220 | ||
2221 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
ff3fccb3 | 2222 | if (res->fi && res->fi->fib_nhs > 1) |
1b7fe593 | 2223 | fib_select_multipath(res); |
1da177e4 LT |
2224 | #endif |
2225 | ||
2226 | /* create a routing cache entry */ | |
2227 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth); | |
2228 | if (err) | |
2229 | return err; | |
1da177e4 LT |
2230 | |
2231 | /* put it into the cache */ | |
68a5e3dd | 2232 | hash = rt_hash(daddr, saddr, fl4->flowi4_iif, |
d8d1f30b | 2233 | rt_genid(dev_net(rth->dst.dev))); |
68a5e3dd | 2234 | rth = rt_intern_hash(hash, rth, skb, fl4->flowi4_iif); |
b23dd4fe DM |
2235 | if (IS_ERR(rth)) |
2236 | return PTR_ERR(rth); | |
2237 | return 0; | |
1da177e4 LT |
2238 | } |
2239 | ||
1da177e4 LT |
2240 | /* |
2241 | * NOTE. We drop all the packets that has local source | |
2242 | * addresses, because every properly looped back packet | |
2243 | * must have correct destination already attached by output routine. | |
2244 | * | |
2245 | * Such approach solves two big problems: | |
2246 | * 1. Not simplex devices are handled properly. | |
2247 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
ebc0ffae | 2248 | * called with rcu_read_lock() |
1da177e4 LT |
2249 | */ |
2250 | ||
9e12bb22 | 2251 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
2252 | u8 tos, struct net_device *dev) |
2253 | { | |
2254 | struct fib_result res; | |
96d36220 | 2255 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
68a5e3dd | 2256 | struct flowi4 fl4; |
1da177e4 LT |
2257 | unsigned flags = 0; |
2258 | u32 itag = 0; | |
2259 | struct rtable * rth; | |
2260 | unsigned hash; | |
9e12bb22 | 2261 | __be32 spec_dst; |
1da177e4 | 2262 | int err = -EINVAL; |
c346dca1 | 2263 | struct net * net = dev_net(dev); |
1da177e4 LT |
2264 | |
2265 | /* IP on this device is disabled. */ | |
2266 | ||
2267 | if (!in_dev) | |
2268 | goto out; | |
2269 | ||
2270 | /* Check for the most weird martians, which can be not detected | |
2271 | by fib_lookup. | |
2272 | */ | |
2273 | ||
1e637c74 | 2274 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
f97c1e0c | 2275 | ipv4_is_loopback(saddr)) |
1da177e4 LT |
2276 | goto martian_source; |
2277 | ||
27a954bd | 2278 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) |
1da177e4 LT |
2279 | goto brd_input; |
2280 | ||
2281 | /* Accept zero addresses only to limited broadcast; | |
2282 | * I even do not know to fix it or not. Waiting for complains :-) | |
2283 | */ | |
f97c1e0c | 2284 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2285 | goto martian_source; |
2286 | ||
27a954bd | 2287 | if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr)) |
1da177e4 LT |
2288 | goto martian_destination; |
2289 | ||
2290 | /* | |
2291 | * Now we are ready to route packet. | |
2292 | */ | |
68a5e3dd DM |
2293 | fl4.flowi4_oif = 0; |
2294 | fl4.flowi4_iif = dev->ifindex; | |
2295 | fl4.flowi4_mark = skb->mark; | |
2296 | fl4.flowi4_tos = tos; | |
2297 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
2298 | fl4.daddr = daddr; | |
2299 | fl4.saddr = saddr; | |
2300 | err = fib_lookup(net, &fl4, &res); | |
ebc0ffae | 2301 | if (err != 0) { |
1da177e4 | 2302 | if (!IN_DEV_FORWARD(in_dev)) |
2c2910a4 | 2303 | goto e_hostunreach; |
1da177e4 LT |
2304 | goto no_route; |
2305 | } | |
1da177e4 LT |
2306 | |
2307 | RT_CACHE_STAT_INC(in_slow_tot); | |
2308 | ||
2309 | if (res.type == RTN_BROADCAST) | |
2310 | goto brd_input; | |
2311 | ||
2312 | if (res.type == RTN_LOCAL) { | |
5c04c819 | 2313 | err = fib_validate_source(skb, saddr, daddr, tos, |
ebc0ffae | 2314 | net->loopback_dev->ifindex, |
5c04c819 | 2315 | dev, &spec_dst, &itag); |
b5f7e755 ED |
2316 | if (err < 0) |
2317 | goto martian_source_keep_err; | |
2318 | if (err) | |
1da177e4 LT |
2319 | flags |= RTCF_DIRECTSRC; |
2320 | spec_dst = daddr; | |
2321 | goto local_input; | |
2322 | } | |
2323 | ||
2324 | if (!IN_DEV_FORWARD(in_dev)) | |
2c2910a4 | 2325 | goto e_hostunreach; |
1da177e4 LT |
2326 | if (res.type != RTN_UNICAST) |
2327 | goto martian_destination; | |
2328 | ||
68a5e3dd | 2329 | err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos); |
1da177e4 LT |
2330 | out: return err; |
2331 | ||
2332 | brd_input: | |
2333 | if (skb->protocol != htons(ETH_P_IP)) | |
2334 | goto e_inval; | |
2335 | ||
f97c1e0c | 2336 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2337 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); |
2338 | else { | |
5c04c819 MS |
2339 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, &spec_dst, |
2340 | &itag); | |
1da177e4 | 2341 | if (err < 0) |
b5f7e755 | 2342 | goto martian_source_keep_err; |
1da177e4 LT |
2343 | if (err) |
2344 | flags |= RTCF_DIRECTSRC; | |
2345 | } | |
2346 | flags |= RTCF_BROADCAST; | |
2347 | res.type = RTN_BROADCAST; | |
2348 | RT_CACHE_STAT_INC(in_brd); | |
2349 | ||
2350 | local_input: | |
5c1e6aa3 DM |
2351 | rth = rt_dst_alloc(net->loopback_dev, |
2352 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); | |
1da177e4 LT |
2353 | if (!rth) |
2354 | goto e_nobufs; | |
2355 | ||
cf911662 | 2356 | rth->dst.input= ip_local_deliver; |
d8d1f30b | 2357 | rth->dst.output= ip_rt_bug; |
cf911662 DM |
2358 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2359 | rth->dst.tclassid = itag; | |
2360 | #endif | |
1da177e4 | 2361 | |
5e2b61f7 | 2362 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2363 | rth->rt_key_src = saddr; |
cf911662 DM |
2364 | rth->rt_genid = rt_genid(net); |
2365 | rth->rt_flags = flags|RTCF_LOCAL; | |
2366 | rth->rt_type = res.type; | |
475949d8 | 2367 | rth->rt_key_tos = tos; |
cf911662 | 2368 | rth->rt_dst = daddr; |
1da177e4 | 2369 | rth->rt_src = saddr; |
c7066f70 | 2370 | #ifdef CONFIG_IP_ROUTE_CLASSID |
d8d1f30b | 2371 | rth->dst.tclassid = itag; |
1da177e4 | 2372 | #endif |
1b86a58f | 2373 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2374 | rth->rt_iif = dev->ifindex; |
cf911662 DM |
2375 | rth->rt_oif = 0; |
2376 | rth->rt_mark = skb->mark; | |
1da177e4 LT |
2377 | rth->rt_gateway = daddr; |
2378 | rth->rt_spec_dst= spec_dst; | |
cf911662 DM |
2379 | rth->rt_peer_genid = 0; |
2380 | rth->peer = NULL; | |
2381 | rth->fi = NULL; | |
1da177e4 | 2382 | if (res.type == RTN_UNREACHABLE) { |
d8d1f30b CG |
2383 | rth->dst.input= ip_error; |
2384 | rth->dst.error= -err; | |
1da177e4 LT |
2385 | rth->rt_flags &= ~RTCF_LOCAL; |
2386 | } | |
68a5e3dd DM |
2387 | hash = rt_hash(daddr, saddr, fl4.flowi4_iif, rt_genid(net)); |
2388 | rth = rt_intern_hash(hash, rth, skb, fl4.flowi4_iif); | |
b23dd4fe DM |
2389 | err = 0; |
2390 | if (IS_ERR(rth)) | |
2391 | err = PTR_ERR(rth); | |
ebc0ffae | 2392 | goto out; |
1da177e4 LT |
2393 | |
2394 | no_route: | |
2395 | RT_CACHE_STAT_INC(in_no_route); | |
2396 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
2397 | res.type = RTN_UNREACHABLE; | |
7f53878d MC |
2398 | if (err == -ESRCH) |
2399 | err = -ENETUNREACH; | |
1da177e4 LT |
2400 | goto local_input; |
2401 | ||
2402 | /* | |
2403 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2404 | */ | |
2405 | martian_destination: | |
2406 | RT_CACHE_STAT_INC(in_martian_dst); | |
2407 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2408 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
058bd4d2 | 2409 | pr_warn("martian destination %pI4 from %pI4, dev %s\n", |
673d57e7 | 2410 | &daddr, &saddr, dev->name); |
1da177e4 | 2411 | #endif |
2c2910a4 DE |
2412 | |
2413 | e_hostunreach: | |
e905a9ed | 2414 | err = -EHOSTUNREACH; |
ebc0ffae | 2415 | goto out; |
2c2910a4 | 2416 | |
1da177e4 LT |
2417 | e_inval: |
2418 | err = -EINVAL; | |
ebc0ffae | 2419 | goto out; |
1da177e4 LT |
2420 | |
2421 | e_nobufs: | |
2422 | err = -ENOBUFS; | |
ebc0ffae | 2423 | goto out; |
1da177e4 LT |
2424 | |
2425 | martian_source: | |
b5f7e755 ED |
2426 | err = -EINVAL; |
2427 | martian_source_keep_err: | |
1da177e4 | 2428 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); |
ebc0ffae | 2429 | goto out; |
1da177e4 LT |
2430 | } |
2431 | ||
407eadd9 ED |
2432 | int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
2433 | u8 tos, struct net_device *dev, bool noref) | |
1da177e4 LT |
2434 | { |
2435 | struct rtable * rth; | |
2436 | unsigned hash; | |
2437 | int iif = dev->ifindex; | |
b5921910 | 2438 | struct net *net; |
96d36220 | 2439 | int res; |
1da177e4 | 2440 | |
c346dca1 | 2441 | net = dev_net(dev); |
1080d709 | 2442 | |
96d36220 ED |
2443 | rcu_read_lock(); |
2444 | ||
1080d709 NH |
2445 | if (!rt_caching(net)) |
2446 | goto skip_cache; | |
2447 | ||
1da177e4 | 2448 | tos &= IPTOS_RT_MASK; |
e84f84f2 | 2449 | hash = rt_hash(daddr, saddr, iif, rt_genid(net)); |
1da177e4 | 2450 | |
1da177e4 | 2451 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2452 | rth = rcu_dereference(rth->dst.rt_next)) { |
5e2b61f7 DM |
2453 | if ((((__force u32)rth->rt_key_dst ^ (__force u32)daddr) | |
2454 | ((__force u32)rth->rt_key_src ^ (__force u32)saddr) | | |
97a80410 | 2455 | (rth->rt_route_iif ^ iif) | |
475949d8 | 2456 | (rth->rt_key_tos ^ tos)) == 0 && |
5e2b61f7 | 2457 | rth->rt_mark == skb->mark && |
d8d1f30b | 2458 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2459 | !rt_is_expired(rth)) { |
de398fb8 | 2460 | ipv4_validate_peer(rth); |
407eadd9 | 2461 | if (noref) { |
d8d1f30b CG |
2462 | dst_use_noref(&rth->dst, jiffies); |
2463 | skb_dst_set_noref(skb, &rth->dst); | |
407eadd9 | 2464 | } else { |
d8d1f30b CG |
2465 | dst_use(&rth->dst, jiffies); |
2466 | skb_dst_set(skb, &rth->dst); | |
407eadd9 | 2467 | } |
1da177e4 LT |
2468 | RT_CACHE_STAT_INC(in_hit); |
2469 | rcu_read_unlock(); | |
1da177e4 LT |
2470 | return 0; |
2471 | } | |
2472 | RT_CACHE_STAT_INC(in_hlist_search); | |
2473 | } | |
1da177e4 | 2474 | |
1080d709 | 2475 | skip_cache: |
1da177e4 LT |
2476 | /* Multicast recognition logic is moved from route cache to here. |
2477 | The problem was that too many Ethernet cards have broken/missing | |
2478 | hardware multicast filters :-( As result the host on multicasting | |
2479 | network acquires a lot of useless route cache entries, sort of | |
2480 | SDR messages from all the world. Now we try to get rid of them. | |
2481 | Really, provided software IP multicast filter is organized | |
2482 | reasonably (at least, hashed), it does not result in a slowdown | |
2483 | comparing with route cache reject entries. | |
2484 | Note, that multicast routers are not affected, because | |
2485 | route cache entry is created eventually. | |
2486 | */ | |
f97c1e0c | 2487 | if (ipv4_is_multicast(daddr)) { |
96d36220 | 2488 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2489 | |
96d36220 | 2490 | if (in_dev) { |
dbdd9a52 DM |
2491 | int our = ip_check_mc_rcu(in_dev, daddr, saddr, |
2492 | ip_hdr(skb)->protocol); | |
1da177e4 LT |
2493 | if (our |
2494 | #ifdef CONFIG_IP_MROUTE | |
9d4fb27d JP |
2495 | || |
2496 | (!ipv4_is_local_multicast(daddr) && | |
2497 | IN_DEV_MFORWARD(in_dev)) | |
1da177e4 | 2498 | #endif |
9d4fb27d | 2499 | ) { |
96d36220 ED |
2500 | int res = ip_route_input_mc(skb, daddr, saddr, |
2501 | tos, dev, our); | |
1da177e4 | 2502 | rcu_read_unlock(); |
96d36220 | 2503 | return res; |
1da177e4 LT |
2504 | } |
2505 | } | |
2506 | rcu_read_unlock(); | |
2507 | return -EINVAL; | |
2508 | } | |
96d36220 ED |
2509 | res = ip_route_input_slow(skb, daddr, saddr, tos, dev); |
2510 | rcu_read_unlock(); | |
2511 | return res; | |
1da177e4 | 2512 | } |
407eadd9 | 2513 | EXPORT_SYMBOL(ip_route_input_common); |
1da177e4 | 2514 | |
ebc0ffae | 2515 | /* called with rcu_read_lock() */ |
982721f3 | 2516 | static struct rtable *__mkroute_output(const struct fib_result *res, |
68a5e3dd | 2517 | const struct flowi4 *fl4, |
813b3b5d | 2518 | __be32 orig_daddr, __be32 orig_saddr, |
f61759e6 JA |
2519 | int orig_oif, __u8 orig_rtos, |
2520 | struct net_device *dev_out, | |
5ada5527 | 2521 | unsigned int flags) |
1da177e4 | 2522 | { |
982721f3 | 2523 | struct fib_info *fi = res->fi; |
5ada5527 | 2524 | struct in_device *in_dev; |
982721f3 | 2525 | u16 type = res->type; |
5ada5527 | 2526 | struct rtable *rth; |
1da177e4 | 2527 | |
68a5e3dd | 2528 | if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) |
5ada5527 | 2529 | return ERR_PTR(-EINVAL); |
1da177e4 | 2530 | |
68a5e3dd | 2531 | if (ipv4_is_lbcast(fl4->daddr)) |
982721f3 | 2532 | type = RTN_BROADCAST; |
68a5e3dd | 2533 | else if (ipv4_is_multicast(fl4->daddr)) |
982721f3 | 2534 | type = RTN_MULTICAST; |
68a5e3dd | 2535 | else if (ipv4_is_zeronet(fl4->daddr)) |
5ada5527 | 2536 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
2537 | |
2538 | if (dev_out->flags & IFF_LOOPBACK) | |
2539 | flags |= RTCF_LOCAL; | |
2540 | ||
dd28d1a0 | 2541 | in_dev = __in_dev_get_rcu(dev_out); |
ebc0ffae | 2542 | if (!in_dev) |
5ada5527 | 2543 | return ERR_PTR(-EINVAL); |
ebc0ffae | 2544 | |
982721f3 | 2545 | if (type == RTN_BROADCAST) { |
1da177e4 | 2546 | flags |= RTCF_BROADCAST | RTCF_LOCAL; |
982721f3 DM |
2547 | fi = NULL; |
2548 | } else if (type == RTN_MULTICAST) { | |
dd28d1a0 | 2549 | flags |= RTCF_MULTICAST | RTCF_LOCAL; |
813b3b5d DM |
2550 | if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, |
2551 | fl4->flowi4_proto)) | |
1da177e4 LT |
2552 | flags &= ~RTCF_LOCAL; |
2553 | /* If multicast route do not exist use | |
dd28d1a0 ED |
2554 | * default one, but do not gateway in this case. |
2555 | * Yes, it is hack. | |
1da177e4 | 2556 | */ |
982721f3 DM |
2557 | if (fi && res->prefixlen < 4) |
2558 | fi = NULL; | |
1da177e4 LT |
2559 | } |
2560 | ||
5c1e6aa3 DM |
2561 | rth = rt_dst_alloc(dev_out, |
2562 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2563 | IN_DEV_CONF_GET(in_dev, NOXFRM)); |
8391d07b | 2564 | if (!rth) |
5ada5527 | 2565 | return ERR_PTR(-ENOBUFS); |
8391d07b | 2566 | |
cf911662 DM |
2567 | rth->dst.output = ip_output; |
2568 | ||
813b3b5d DM |
2569 | rth->rt_key_dst = orig_daddr; |
2570 | rth->rt_key_src = orig_saddr; | |
cf911662 DM |
2571 | rth->rt_genid = rt_genid(dev_net(dev_out)); |
2572 | rth->rt_flags = flags; | |
2573 | rth->rt_type = type; | |
f61759e6 | 2574 | rth->rt_key_tos = orig_rtos; |
68a5e3dd DM |
2575 | rth->rt_dst = fl4->daddr; |
2576 | rth->rt_src = fl4->saddr; | |
1b86a58f | 2577 | rth->rt_route_iif = 0; |
813b3b5d DM |
2578 | rth->rt_iif = orig_oif ? : dev_out->ifindex; |
2579 | rth->rt_oif = orig_oif; | |
2580 | rth->rt_mark = fl4->flowi4_mark; | |
68a5e3dd DM |
2581 | rth->rt_gateway = fl4->daddr; |
2582 | rth->rt_spec_dst= fl4->saddr; | |
cf911662 DM |
2583 | rth->rt_peer_genid = 0; |
2584 | rth->peer = NULL; | |
2585 | rth->fi = NULL; | |
1da177e4 LT |
2586 | |
2587 | RT_CACHE_STAT_INC(out_slow_tot); | |
2588 | ||
2589 | if (flags & RTCF_LOCAL) { | |
d8d1f30b | 2590 | rth->dst.input = ip_local_deliver; |
68a5e3dd | 2591 | rth->rt_spec_dst = fl4->daddr; |
1da177e4 LT |
2592 | } |
2593 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { | |
68a5e3dd | 2594 | rth->rt_spec_dst = fl4->saddr; |
e905a9ed | 2595 | if (flags & RTCF_LOCAL && |
1da177e4 | 2596 | !(dev_out->flags & IFF_LOOPBACK)) { |
d8d1f30b | 2597 | rth->dst.output = ip_mc_output; |
1da177e4 LT |
2598 | RT_CACHE_STAT_INC(out_slow_mc); |
2599 | } | |
2600 | #ifdef CONFIG_IP_MROUTE | |
982721f3 | 2601 | if (type == RTN_MULTICAST) { |
1da177e4 | 2602 | if (IN_DEV_MFORWARD(in_dev) && |
813b3b5d | 2603 | !ipv4_is_local_multicast(fl4->daddr)) { |
d8d1f30b CG |
2604 | rth->dst.input = ip_mr_input; |
2605 | rth->dst.output = ip_mc_output; | |
1da177e4 LT |
2606 | } |
2607 | } | |
2608 | #endif | |
2609 | } | |
2610 | ||
813b3b5d | 2611 | rt_set_nexthop(rth, fl4, res, fi, type, 0); |
1da177e4 | 2612 | |
5ada5527 | 2613 | return rth; |
1da177e4 LT |
2614 | } |
2615 | ||
1da177e4 LT |
2616 | /* |
2617 | * Major route resolver routine. | |
0197aa38 | 2618 | * called with rcu_read_lock(); |
1da177e4 LT |
2619 | */ |
2620 | ||
813b3b5d | 2621 | static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4) |
1da177e4 | 2622 | { |
1da177e4 | 2623 | struct net_device *dev_out = NULL; |
f61759e6 | 2624 | __u8 tos = RT_FL_TOS(fl4); |
813b3b5d DM |
2625 | unsigned int flags = 0; |
2626 | struct fib_result res; | |
5ada5527 | 2627 | struct rtable *rth; |
813b3b5d DM |
2628 | __be32 orig_daddr; |
2629 | __be32 orig_saddr; | |
2630 | int orig_oif; | |
1da177e4 LT |
2631 | |
2632 | res.fi = NULL; | |
2633 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
2634 | res.r = NULL; | |
2635 | #endif | |
2636 | ||
813b3b5d DM |
2637 | orig_daddr = fl4->daddr; |
2638 | orig_saddr = fl4->saddr; | |
2639 | orig_oif = fl4->flowi4_oif; | |
2640 | ||
2641 | fl4->flowi4_iif = net->loopback_dev->ifindex; | |
2642 | fl4->flowi4_tos = tos & IPTOS_RT_MASK; | |
2643 | fl4->flowi4_scope = ((tos & RTO_ONLINK) ? | |
2644 | RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); | |
44713b67 | 2645 | |
010c2708 | 2646 | rcu_read_lock(); |
813b3b5d | 2647 | if (fl4->saddr) { |
b23dd4fe | 2648 | rth = ERR_PTR(-EINVAL); |
813b3b5d DM |
2649 | if (ipv4_is_multicast(fl4->saddr) || |
2650 | ipv4_is_lbcast(fl4->saddr) || | |
2651 | ipv4_is_zeronet(fl4->saddr)) | |
1da177e4 LT |
2652 | goto out; |
2653 | ||
1da177e4 LT |
2654 | /* I removed check for oif == dev_out->oif here. |
2655 | It was wrong for two reasons: | |
1ab35276 DL |
2656 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr |
2657 | is assigned to multiple interfaces. | |
1da177e4 LT |
2658 | 2. Moreover, we are allowed to send packets with saddr |
2659 | of another iface. --ANK | |
2660 | */ | |
2661 | ||
813b3b5d DM |
2662 | if (fl4->flowi4_oif == 0 && |
2663 | (ipv4_is_multicast(fl4->daddr) || | |
2664 | ipv4_is_lbcast(fl4->daddr))) { | |
a210d01a | 2665 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2666 | dev_out = __ip_dev_find(net, fl4->saddr, false); |
a210d01a JA |
2667 | if (dev_out == NULL) |
2668 | goto out; | |
2669 | ||
1da177e4 LT |
2670 | /* Special hack: user can direct multicasts |
2671 | and limited broadcast via necessary interface | |
2672 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2673 | This hack is not just for fun, it allows | |
2674 | vic,vat and friends to work. | |
2675 | They bind socket to loopback, set ttl to zero | |
2676 | and expect that it will work. | |
2677 | From the viewpoint of routing cache they are broken, | |
2678 | because we are not allowed to build multicast path | |
2679 | with loopback source addr (look, routing cache | |
2680 | cannot know, that ttl is zero, so that packet | |
2681 | will not leave this host and route is valid). | |
2682 | Luckily, this hack is good workaround. | |
2683 | */ | |
2684 | ||
813b3b5d | 2685 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2686 | goto make_route; |
2687 | } | |
a210d01a | 2688 | |
813b3b5d | 2689 | if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { |
a210d01a | 2690 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2691 | if (!__ip_dev_find(net, fl4->saddr, false)) |
a210d01a | 2692 | goto out; |
a210d01a | 2693 | } |
1da177e4 LT |
2694 | } |
2695 | ||
2696 | ||
813b3b5d DM |
2697 | if (fl4->flowi4_oif) { |
2698 | dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); | |
b23dd4fe | 2699 | rth = ERR_PTR(-ENODEV); |
1da177e4 LT |
2700 | if (dev_out == NULL) |
2701 | goto out; | |
e5ed6399 HX |
2702 | |
2703 | /* RACE: Check return value of inet_select_addr instead. */ | |
fc75fc83 | 2704 | if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { |
b23dd4fe | 2705 | rth = ERR_PTR(-ENETUNREACH); |
fc75fc83 ED |
2706 | goto out; |
2707 | } | |
813b3b5d DM |
2708 | if (ipv4_is_local_multicast(fl4->daddr) || |
2709 | ipv4_is_lbcast(fl4->daddr)) { | |
2710 | if (!fl4->saddr) | |
2711 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2712 | RT_SCOPE_LINK); | |
1da177e4 LT |
2713 | goto make_route; |
2714 | } | |
813b3b5d DM |
2715 | if (fl4->saddr) { |
2716 | if (ipv4_is_multicast(fl4->daddr)) | |
2717 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2718 | fl4->flowi4_scope); | |
2719 | else if (!fl4->daddr) | |
2720 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2721 | RT_SCOPE_HOST); | |
1da177e4 LT |
2722 | } |
2723 | } | |
2724 | ||
813b3b5d DM |
2725 | if (!fl4->daddr) { |
2726 | fl4->daddr = fl4->saddr; | |
2727 | if (!fl4->daddr) | |
2728 | fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); | |
b40afd0e | 2729 | dev_out = net->loopback_dev; |
813b3b5d | 2730 | fl4->flowi4_oif = net->loopback_dev->ifindex; |
1da177e4 LT |
2731 | res.type = RTN_LOCAL; |
2732 | flags |= RTCF_LOCAL; | |
2733 | goto make_route; | |
2734 | } | |
2735 | ||
813b3b5d | 2736 | if (fib_lookup(net, fl4, &res)) { |
1da177e4 | 2737 | res.fi = NULL; |
813b3b5d | 2738 | if (fl4->flowi4_oif) { |
1da177e4 LT |
2739 | /* Apparently, routing tables are wrong. Assume, |
2740 | that the destination is on link. | |
2741 | ||
2742 | WHY? DW. | |
2743 | Because we are allowed to send to iface | |
2744 | even if it has NO routes and NO assigned | |
2745 | addresses. When oif is specified, routing | |
2746 | tables are looked up with only one purpose: | |
2747 | to catch if destination is gatewayed, rather than | |
2748 | direct. Moreover, if MSG_DONTROUTE is set, | |
2749 | we send packet, ignoring both routing tables | |
2750 | and ifaddr state. --ANK | |
2751 | ||
2752 | ||
2753 | We could make it even if oif is unknown, | |
2754 | likely IPv6, but we do not. | |
2755 | */ | |
2756 | ||
813b3b5d DM |
2757 | if (fl4->saddr == 0) |
2758 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2759 | RT_SCOPE_LINK); | |
1da177e4 LT |
2760 | res.type = RTN_UNICAST; |
2761 | goto make_route; | |
2762 | } | |
b23dd4fe | 2763 | rth = ERR_PTR(-ENETUNREACH); |
1da177e4 LT |
2764 | goto out; |
2765 | } | |
1da177e4 LT |
2766 | |
2767 | if (res.type == RTN_LOCAL) { | |
813b3b5d | 2768 | if (!fl4->saddr) { |
9fc3bbb4 | 2769 | if (res.fi->fib_prefsrc) |
813b3b5d | 2770 | fl4->saddr = res.fi->fib_prefsrc; |
9fc3bbb4 | 2771 | else |
813b3b5d | 2772 | fl4->saddr = fl4->daddr; |
9fc3bbb4 | 2773 | } |
b40afd0e | 2774 | dev_out = net->loopback_dev; |
813b3b5d | 2775 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2776 | res.fi = NULL; |
2777 | flags |= RTCF_LOCAL; | |
2778 | goto make_route; | |
2779 | } | |
2780 | ||
2781 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
813b3b5d | 2782 | if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0) |
1b7fe593 | 2783 | fib_select_multipath(&res); |
1da177e4 LT |
2784 | else |
2785 | #endif | |
21d8c49e DM |
2786 | if (!res.prefixlen && |
2787 | res.table->tb_num_default > 1 && | |
813b3b5d | 2788 | res.type == RTN_UNICAST && !fl4->flowi4_oif) |
0c838ff1 | 2789 | fib_select_default(&res); |
1da177e4 | 2790 | |
813b3b5d DM |
2791 | if (!fl4->saddr) |
2792 | fl4->saddr = FIB_RES_PREFSRC(net, res); | |
1da177e4 | 2793 | |
1da177e4 | 2794 | dev_out = FIB_RES_DEV(res); |
813b3b5d | 2795 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2796 | |
2797 | ||
2798 | make_route: | |
813b3b5d | 2799 | rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif, |
f61759e6 | 2800 | tos, dev_out, flags); |
b23dd4fe | 2801 | if (!IS_ERR(rth)) { |
5ada5527 DM |
2802 | unsigned int hash; |
2803 | ||
813b3b5d | 2804 | hash = rt_hash(orig_daddr, orig_saddr, orig_oif, |
5ada5527 | 2805 | rt_genid(dev_net(dev_out))); |
813b3b5d | 2806 | rth = rt_intern_hash(hash, rth, NULL, orig_oif); |
5ada5527 | 2807 | } |
1da177e4 | 2808 | |
010c2708 DM |
2809 | out: |
2810 | rcu_read_unlock(); | |
b23dd4fe | 2811 | return rth; |
1da177e4 LT |
2812 | } |
2813 | ||
813b3b5d | 2814 | struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4) |
1da177e4 | 2815 | { |
1da177e4 | 2816 | struct rtable *rth; |
010c2708 | 2817 | unsigned int hash; |
1da177e4 | 2818 | |
1080d709 NH |
2819 | if (!rt_caching(net)) |
2820 | goto slow_output; | |
2821 | ||
9d6ec938 | 2822 | hash = rt_hash(flp4->daddr, flp4->saddr, flp4->flowi4_oif, rt_genid(net)); |
1da177e4 LT |
2823 | |
2824 | rcu_read_lock_bh(); | |
a898def2 | 2825 | for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2826 | rth = rcu_dereference_bh(rth->dst.rt_next)) { |
9d6ec938 DM |
2827 | if (rth->rt_key_dst == flp4->daddr && |
2828 | rth->rt_key_src == flp4->saddr && | |
c7537967 | 2829 | rt_is_output_route(rth) && |
9d6ec938 DM |
2830 | rth->rt_oif == flp4->flowi4_oif && |
2831 | rth->rt_mark == flp4->flowi4_mark && | |
475949d8 | 2832 | !((rth->rt_key_tos ^ flp4->flowi4_tos) & |
b5921910 | 2833 | (IPTOS_RT_MASK | RTO_ONLINK)) && |
d8d1f30b | 2834 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2835 | !rt_is_expired(rth)) { |
de398fb8 | 2836 | ipv4_validate_peer(rth); |
d8d1f30b | 2837 | dst_use(&rth->dst, jiffies); |
1da177e4 LT |
2838 | RT_CACHE_STAT_INC(out_hit); |
2839 | rcu_read_unlock_bh(); | |
56157872 DM |
2840 | if (!flp4->saddr) |
2841 | flp4->saddr = rth->rt_src; | |
2842 | if (!flp4->daddr) | |
2843 | flp4->daddr = rth->rt_dst; | |
b23dd4fe | 2844 | return rth; |
1da177e4 LT |
2845 | } |
2846 | RT_CACHE_STAT_INC(out_hlist_search); | |
2847 | } | |
2848 | rcu_read_unlock_bh(); | |
2849 | ||
1080d709 | 2850 | slow_output: |
9d6ec938 | 2851 | return ip_route_output_slow(net, flp4); |
1da177e4 | 2852 | } |
d8c97a94 ACM |
2853 | EXPORT_SYMBOL_GPL(__ip_route_output_key); |
2854 | ||
ae2688d5 JW |
2855 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) |
2856 | { | |
2857 | return NULL; | |
2858 | } | |
2859 | ||
ebb762f2 | 2860 | static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst) |
ec831ea7 | 2861 | { |
618f9bc7 SK |
2862 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
2863 | ||
2864 | return mtu ? : dst->dev->mtu; | |
ec831ea7 RD |
2865 | } |
2866 | ||
14e50e57 DM |
2867 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) |
2868 | { | |
2869 | } | |
2870 | ||
0972ddb2 HB |
2871 | static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, |
2872 | unsigned long old) | |
2873 | { | |
2874 | return NULL; | |
2875 | } | |
2876 | ||
14e50e57 DM |
2877 | static struct dst_ops ipv4_dst_blackhole_ops = { |
2878 | .family = AF_INET, | |
09640e63 | 2879 | .protocol = cpu_to_be16(ETH_P_IP), |
14e50e57 | 2880 | .destroy = ipv4_dst_destroy, |
ae2688d5 | 2881 | .check = ipv4_blackhole_dst_check, |
ebb762f2 | 2882 | .mtu = ipv4_blackhole_mtu, |
214f45c9 | 2883 | .default_advmss = ipv4_default_advmss, |
14e50e57 | 2884 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, |
0972ddb2 | 2885 | .cow_metrics = ipv4_rt_blackhole_cow_metrics, |
d3aaeb38 | 2886 | .neigh_lookup = ipv4_neigh_lookup, |
14e50e57 DM |
2887 | }; |
2888 | ||
2774c131 | 2889 | struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) |
14e50e57 | 2890 | { |
5c1e6aa3 | 2891 | struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, 0, 0); |
2774c131 | 2892 | struct rtable *ort = (struct rtable *) dst_orig; |
14e50e57 DM |
2893 | |
2894 | if (rt) { | |
d8d1f30b | 2895 | struct dst_entry *new = &rt->dst; |
14e50e57 | 2896 | |
14e50e57 | 2897 | new->__use = 1; |
352e512c HX |
2898 | new->input = dst_discard; |
2899 | new->output = dst_discard; | |
defb3519 | 2900 | dst_copy_metrics(new, &ort->dst); |
14e50e57 | 2901 | |
d8d1f30b | 2902 | new->dev = ort->dst.dev; |
14e50e57 DM |
2903 | if (new->dev) |
2904 | dev_hold(new->dev); | |
2905 | ||
5e2b61f7 DM |
2906 | rt->rt_key_dst = ort->rt_key_dst; |
2907 | rt->rt_key_src = ort->rt_key_src; | |
475949d8 | 2908 | rt->rt_key_tos = ort->rt_key_tos; |
1b86a58f | 2909 | rt->rt_route_iif = ort->rt_route_iif; |
5e2b61f7 DM |
2910 | rt->rt_iif = ort->rt_iif; |
2911 | rt->rt_oif = ort->rt_oif; | |
2912 | rt->rt_mark = ort->rt_mark; | |
14e50e57 | 2913 | |
e84f84f2 | 2914 | rt->rt_genid = rt_genid(net); |
14e50e57 DM |
2915 | rt->rt_flags = ort->rt_flags; |
2916 | rt->rt_type = ort->rt_type; | |
2917 | rt->rt_dst = ort->rt_dst; | |
2918 | rt->rt_src = ort->rt_src; | |
14e50e57 DM |
2919 | rt->rt_gateway = ort->rt_gateway; |
2920 | rt->rt_spec_dst = ort->rt_spec_dst; | |
2921 | rt->peer = ort->peer; | |
2922 | if (rt->peer) | |
2923 | atomic_inc(&rt->peer->refcnt); | |
62fa8a84 DM |
2924 | rt->fi = ort->fi; |
2925 | if (rt->fi) | |
2926 | atomic_inc(&rt->fi->fib_clntref); | |
14e50e57 DM |
2927 | |
2928 | dst_free(new); | |
2929 | } | |
2930 | ||
2774c131 DM |
2931 | dst_release(dst_orig); |
2932 | ||
2933 | return rt ? &rt->dst : ERR_PTR(-ENOMEM); | |
14e50e57 DM |
2934 | } |
2935 | ||
9d6ec938 | 2936 | struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, |
b23dd4fe | 2937 | struct sock *sk) |
1da177e4 | 2938 | { |
9d6ec938 | 2939 | struct rtable *rt = __ip_route_output_key(net, flp4); |
1da177e4 | 2940 | |
b23dd4fe DM |
2941 | if (IS_ERR(rt)) |
2942 | return rt; | |
1da177e4 | 2943 | |
56157872 | 2944 | if (flp4->flowi4_proto) |
9d6ec938 DM |
2945 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
2946 | flowi4_to_flowi(flp4), | |
2947 | sk, 0); | |
1da177e4 | 2948 | |
b23dd4fe | 2949 | return rt; |
1da177e4 | 2950 | } |
d8c97a94 ACM |
2951 | EXPORT_SYMBOL_GPL(ip_route_output_flow); |
2952 | ||
4feb88e5 BT |
2953 | static int rt_fill_info(struct net *net, |
2954 | struct sk_buff *skb, u32 pid, u32 seq, int event, | |
b6544c0b | 2955 | int nowait, unsigned int flags) |
1da177e4 | 2956 | { |
511c3f92 | 2957 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 2958 | struct rtmsg *r; |
be403ea1 | 2959 | struct nlmsghdr *nlh; |
2bc8ca40 | 2960 | unsigned long expires = 0; |
fe6fe792 | 2961 | const struct inet_peer *peer = rt->peer; |
e3703b3d | 2962 | u32 id = 0, ts = 0, tsage = 0, error; |
be403ea1 TG |
2963 | |
2964 | nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags); | |
2965 | if (nlh == NULL) | |
26932566 | 2966 | return -EMSGSIZE; |
be403ea1 TG |
2967 | |
2968 | r = nlmsg_data(nlh); | |
1da177e4 LT |
2969 | r->rtm_family = AF_INET; |
2970 | r->rtm_dst_len = 32; | |
2971 | r->rtm_src_len = 0; | |
475949d8 | 2972 | r->rtm_tos = rt->rt_key_tos; |
1da177e4 | 2973 | r->rtm_table = RT_TABLE_MAIN; |
be403ea1 | 2974 | NLA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN); |
1da177e4 LT |
2975 | r->rtm_type = rt->rt_type; |
2976 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2977 | r->rtm_protocol = RTPROT_UNSPEC; | |
2978 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2979 | if (rt->rt_flags & RTCF_NOTIFY) | |
2980 | r->rtm_flags |= RTM_F_NOTIFY; | |
be403ea1 | 2981 | |
17fb2c64 | 2982 | NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst); |
be403ea1 | 2983 | |
5e2b61f7 | 2984 | if (rt->rt_key_src) { |
1da177e4 | 2985 | r->rtm_src_len = 32; |
5e2b61f7 | 2986 | NLA_PUT_BE32(skb, RTA_SRC, rt->rt_key_src); |
1da177e4 | 2987 | } |
d8d1f30b CG |
2988 | if (rt->dst.dev) |
2989 | NLA_PUT_U32(skb, RTA_OIF, rt->dst.dev->ifindex); | |
c7066f70 | 2990 | #ifdef CONFIG_IP_ROUTE_CLASSID |
d8d1f30b CG |
2991 | if (rt->dst.tclassid) |
2992 | NLA_PUT_U32(skb, RTA_FLOW, rt->dst.tclassid); | |
1da177e4 | 2993 | #endif |
c7537967 | 2994 | if (rt_is_input_route(rt)) |
17fb2c64 | 2995 | NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_spec_dst); |
5e2b61f7 | 2996 | else if (rt->rt_src != rt->rt_key_src) |
17fb2c64 | 2997 | NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_src); |
be403ea1 | 2998 | |
1da177e4 | 2999 | if (rt->rt_dst != rt->rt_gateway) |
17fb2c64 | 3000 | NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway); |
be403ea1 | 3001 | |
defb3519 | 3002 | if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) |
be403ea1 TG |
3003 | goto nla_put_failure; |
3004 | ||
5e2b61f7 DM |
3005 | if (rt->rt_mark) |
3006 | NLA_PUT_BE32(skb, RTA_MARK, rt->rt_mark); | |
963bfeee | 3007 | |
d8d1f30b | 3008 | error = rt->dst.error; |
fe6fe792 | 3009 | if (peer) { |
317fe0e6 | 3010 | inet_peer_refcheck(rt->peer); |
fe6fe792 ED |
3011 | id = atomic_read(&peer->ip_id_count) & 0xffff; |
3012 | if (peer->tcp_ts_stamp) { | |
3013 | ts = peer->tcp_ts; | |
3014 | tsage = get_seconds() - peer->tcp_ts_stamp; | |
1da177e4 | 3015 | } |
fe6fe792 | 3016 | expires = ACCESS_ONCE(peer->pmtu_expires); |
2bc8ca40 SK |
3017 | if (expires) { |
3018 | if (time_before(jiffies, expires)) | |
3019 | expires -= jiffies; | |
3020 | else | |
3021 | expires = 0; | |
3022 | } | |
1da177e4 | 3023 | } |
be403ea1 | 3024 | |
c7537967 | 3025 | if (rt_is_input_route(rt)) { |
1da177e4 | 3026 | #ifdef CONFIG_IP_MROUTE |
e448515c | 3027 | __be32 dst = rt->rt_dst; |
1da177e4 | 3028 | |
f97c1e0c | 3029 | if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) && |
4feb88e5 | 3030 | IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { |
9a1b9496 DM |
3031 | int err = ipmr_get_route(net, skb, |
3032 | rt->rt_src, rt->rt_dst, | |
3033 | r, nowait); | |
1da177e4 LT |
3034 | if (err <= 0) { |
3035 | if (!nowait) { | |
3036 | if (err == 0) | |
3037 | return 0; | |
be403ea1 | 3038 | goto nla_put_failure; |
1da177e4 LT |
3039 | } else { |
3040 | if (err == -EMSGSIZE) | |
be403ea1 | 3041 | goto nla_put_failure; |
e3703b3d | 3042 | error = err; |
1da177e4 LT |
3043 | } |
3044 | } | |
3045 | } else | |
3046 | #endif | |
5e2b61f7 | 3047 | NLA_PUT_U32(skb, RTA_IIF, rt->rt_iif); |
1da177e4 LT |
3048 | } |
3049 | ||
d8d1f30b | 3050 | if (rtnl_put_cacheinfo(skb, &rt->dst, id, ts, tsage, |
e3703b3d TG |
3051 | expires, error) < 0) |
3052 | goto nla_put_failure; | |
be403ea1 TG |
3053 | |
3054 | return nlmsg_end(skb, nlh); | |
1da177e4 | 3055 | |
be403ea1 | 3056 | nla_put_failure: |
26932566 PM |
3057 | nlmsg_cancel(skb, nlh); |
3058 | return -EMSGSIZE; | |
1da177e4 LT |
3059 | } |
3060 | ||
63f3444f | 3061 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg) |
1da177e4 | 3062 | { |
3b1e0a65 | 3063 | struct net *net = sock_net(in_skb->sk); |
d889ce3b TG |
3064 | struct rtmsg *rtm; |
3065 | struct nlattr *tb[RTA_MAX+1]; | |
1da177e4 | 3066 | struct rtable *rt = NULL; |
9e12bb22 AV |
3067 | __be32 dst = 0; |
3068 | __be32 src = 0; | |
3069 | u32 iif; | |
d889ce3b | 3070 | int err; |
963bfeee | 3071 | int mark; |
1da177e4 LT |
3072 | struct sk_buff *skb; |
3073 | ||
d889ce3b TG |
3074 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); |
3075 | if (err < 0) | |
3076 | goto errout; | |
3077 | ||
3078 | rtm = nlmsg_data(nlh); | |
3079 | ||
1da177e4 | 3080 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
d889ce3b TG |
3081 | if (skb == NULL) { |
3082 | err = -ENOBUFS; | |
3083 | goto errout; | |
3084 | } | |
1da177e4 LT |
3085 | |
3086 | /* Reserve room for dummy headers, this skb can pass | |
3087 | through good chunk of routing engine. | |
3088 | */ | |
459a98ed | 3089 | skb_reset_mac_header(skb); |
c1d2bbe1 | 3090 | skb_reset_network_header(skb); |
d2c962b8 SH |
3091 | |
3092 | /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ | |
eddc9ec5 | 3093 | ip_hdr(skb)->protocol = IPPROTO_ICMP; |
1da177e4 LT |
3094 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); |
3095 | ||
17fb2c64 AV |
3096 | src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0; |
3097 | dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; | |
d889ce3b | 3098 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; |
963bfeee | 3099 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; |
1da177e4 LT |
3100 | |
3101 | if (iif) { | |
d889ce3b TG |
3102 | struct net_device *dev; |
3103 | ||
1937504d | 3104 | dev = __dev_get_by_index(net, iif); |
d889ce3b TG |
3105 | if (dev == NULL) { |
3106 | err = -ENODEV; | |
3107 | goto errout_free; | |
3108 | } | |
3109 | ||
1da177e4 LT |
3110 | skb->protocol = htons(ETH_P_IP); |
3111 | skb->dev = dev; | |
963bfeee | 3112 | skb->mark = mark; |
1da177e4 LT |
3113 | local_bh_disable(); |
3114 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
3115 | local_bh_enable(); | |
d889ce3b | 3116 | |
511c3f92 | 3117 | rt = skb_rtable(skb); |
d8d1f30b CG |
3118 | if (err == 0 && rt->dst.error) |
3119 | err = -rt->dst.error; | |
1da177e4 | 3120 | } else { |
68a5e3dd DM |
3121 | struct flowi4 fl4 = { |
3122 | .daddr = dst, | |
3123 | .saddr = src, | |
3124 | .flowi4_tos = rtm->rtm_tos, | |
3125 | .flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0, | |
3126 | .flowi4_mark = mark, | |
d889ce3b | 3127 | }; |
9d6ec938 | 3128 | rt = ip_route_output_key(net, &fl4); |
b23dd4fe DM |
3129 | |
3130 | err = 0; | |
3131 | if (IS_ERR(rt)) | |
3132 | err = PTR_ERR(rt); | |
1da177e4 | 3133 | } |
d889ce3b | 3134 | |
1da177e4 | 3135 | if (err) |
d889ce3b | 3136 | goto errout_free; |
1da177e4 | 3137 | |
d8d1f30b | 3138 | skb_dst_set(skb, &rt->dst); |
1da177e4 LT |
3139 | if (rtm->rtm_flags & RTM_F_NOTIFY) |
3140 | rt->rt_flags |= RTCF_NOTIFY; | |
3141 | ||
4feb88e5 | 3142 | err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, |
1937504d | 3143 | RTM_NEWROUTE, 0, 0); |
d889ce3b TG |
3144 | if (err <= 0) |
3145 | goto errout_free; | |
1da177e4 | 3146 | |
1937504d | 3147 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); |
d889ce3b | 3148 | errout: |
2942e900 | 3149 | return err; |
1da177e4 | 3150 | |
d889ce3b | 3151 | errout_free: |
1da177e4 | 3152 | kfree_skb(skb); |
d889ce3b | 3153 | goto errout; |
1da177e4 LT |
3154 | } |
3155 | ||
3156 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
3157 | { | |
3158 | struct rtable *rt; | |
3159 | int h, s_h; | |
3160 | int idx, s_idx; | |
1937504d DL |
3161 | struct net *net; |
3162 | ||
3b1e0a65 | 3163 | net = sock_net(skb->sk); |
1da177e4 LT |
3164 | |
3165 | s_h = cb->args[0]; | |
d8c92830 ED |
3166 | if (s_h < 0) |
3167 | s_h = 0; | |
1da177e4 | 3168 | s_idx = idx = cb->args[1]; |
a6272665 ED |
3169 | for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) { |
3170 | if (!rt_hash_table[h].chain) | |
3171 | continue; | |
1da177e4 | 3172 | rcu_read_lock_bh(); |
a898def2 | 3173 | for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt; |
d8d1f30b CG |
3174 | rt = rcu_dereference_bh(rt->dst.rt_next), idx++) { |
3175 | if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx) | |
1da177e4 | 3176 | continue; |
e84f84f2 | 3177 | if (rt_is_expired(rt)) |
29e75252 | 3178 | continue; |
d8d1f30b | 3179 | skb_dst_set_noref(skb, &rt->dst); |
4feb88e5 | 3180 | if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid, |
e905a9ed | 3181 | cb->nlh->nlmsg_seq, RTM_NEWROUTE, |
b6544c0b | 3182 | 1, NLM_F_MULTI) <= 0) { |
adf30907 | 3183 | skb_dst_drop(skb); |
1da177e4 LT |
3184 | rcu_read_unlock_bh(); |
3185 | goto done; | |
3186 | } | |
adf30907 | 3187 | skb_dst_drop(skb); |
1da177e4 LT |
3188 | } |
3189 | rcu_read_unlock_bh(); | |
3190 | } | |
3191 | ||
3192 | done: | |
3193 | cb->args[0] = h; | |
3194 | cb->args[1] = idx; | |
3195 | return skb->len; | |
3196 | } | |
3197 | ||
3198 | void ip_rt_multicast_event(struct in_device *in_dev) | |
3199 | { | |
76e6ebfb | 3200 | rt_cache_flush(dev_net(in_dev->dev), 0); |
1da177e4 LT |
3201 | } |
3202 | ||
3203 | #ifdef CONFIG_SYSCTL | |
81c684d1 | 3204 | static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, |
8d65af78 | 3205 | void __user *buffer, |
1da177e4 LT |
3206 | size_t *lenp, loff_t *ppos) |
3207 | { | |
3208 | if (write) { | |
639e104f | 3209 | int flush_delay; |
81c684d1 | 3210 | ctl_table ctl; |
39a23e75 | 3211 | struct net *net; |
639e104f | 3212 | |
81c684d1 DL |
3213 | memcpy(&ctl, __ctl, sizeof(ctl)); |
3214 | ctl.data = &flush_delay; | |
8d65af78 | 3215 | proc_dointvec(&ctl, write, buffer, lenp, ppos); |
639e104f | 3216 | |
81c684d1 | 3217 | net = (struct net *)__ctl->extra1; |
39a23e75 | 3218 | rt_cache_flush(net, flush_delay); |
1da177e4 | 3219 | return 0; |
e905a9ed | 3220 | } |
1da177e4 LT |
3221 | |
3222 | return -EINVAL; | |
3223 | } | |
3224 | ||
eeb61f71 | 3225 | static ctl_table ipv4_route_table[] = { |
1da177e4 | 3226 | { |
1da177e4 LT |
3227 | .procname = "gc_thresh", |
3228 | .data = &ipv4_dst_ops.gc_thresh, | |
3229 | .maxlen = sizeof(int), | |
3230 | .mode = 0644, | |
6d9f239a | 3231 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3232 | }, |
3233 | { | |
1da177e4 LT |
3234 | .procname = "max_size", |
3235 | .data = &ip_rt_max_size, | |
3236 | .maxlen = sizeof(int), | |
3237 | .mode = 0644, | |
6d9f239a | 3238 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3239 | }, |
3240 | { | |
3241 | /* Deprecated. Use gc_min_interval_ms */ | |
e905a9ed | 3242 | |
1da177e4 LT |
3243 | .procname = "gc_min_interval", |
3244 | .data = &ip_rt_gc_min_interval, | |
3245 | .maxlen = sizeof(int), | |
3246 | .mode = 0644, | |
6d9f239a | 3247 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3248 | }, |
3249 | { | |
1da177e4 LT |
3250 | .procname = "gc_min_interval_ms", |
3251 | .data = &ip_rt_gc_min_interval, | |
3252 | .maxlen = sizeof(int), | |
3253 | .mode = 0644, | |
6d9f239a | 3254 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 LT |
3255 | }, |
3256 | { | |
1da177e4 LT |
3257 | .procname = "gc_timeout", |
3258 | .data = &ip_rt_gc_timeout, | |
3259 | .maxlen = sizeof(int), | |
3260 | .mode = 0644, | |
6d9f239a | 3261 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 | 3262 | }, |
9f28a2fc ED |
3263 | { |
3264 | .procname = "gc_interval", | |
3265 | .data = &ip_rt_gc_interval, | |
3266 | .maxlen = sizeof(int), | |
3267 | .mode = 0644, | |
3268 | .proc_handler = proc_dointvec_jiffies, | |
3269 | }, | |
1da177e4 | 3270 | { |
1da177e4 LT |
3271 | .procname = "redirect_load", |
3272 | .data = &ip_rt_redirect_load, | |
3273 | .maxlen = sizeof(int), | |
3274 | .mode = 0644, | |
6d9f239a | 3275 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3276 | }, |
3277 | { | |
1da177e4 LT |
3278 | .procname = "redirect_number", |
3279 | .data = &ip_rt_redirect_number, | |
3280 | .maxlen = sizeof(int), | |
3281 | .mode = 0644, | |
6d9f239a | 3282 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3283 | }, |
3284 | { | |
1da177e4 LT |
3285 | .procname = "redirect_silence", |
3286 | .data = &ip_rt_redirect_silence, | |
3287 | .maxlen = sizeof(int), | |
3288 | .mode = 0644, | |
6d9f239a | 3289 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3290 | }, |
3291 | { | |
1da177e4 LT |
3292 | .procname = "error_cost", |
3293 | .data = &ip_rt_error_cost, | |
3294 | .maxlen = sizeof(int), | |
3295 | .mode = 0644, | |
6d9f239a | 3296 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3297 | }, |
3298 | { | |
1da177e4 LT |
3299 | .procname = "error_burst", |
3300 | .data = &ip_rt_error_burst, | |
3301 | .maxlen = sizeof(int), | |
3302 | .mode = 0644, | |
6d9f239a | 3303 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3304 | }, |
3305 | { | |
1da177e4 LT |
3306 | .procname = "gc_elasticity", |
3307 | .data = &ip_rt_gc_elasticity, | |
3308 | .maxlen = sizeof(int), | |
3309 | .mode = 0644, | |
6d9f239a | 3310 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3311 | }, |
3312 | { | |
1da177e4 LT |
3313 | .procname = "mtu_expires", |
3314 | .data = &ip_rt_mtu_expires, | |
3315 | .maxlen = sizeof(int), | |
3316 | .mode = 0644, | |
6d9f239a | 3317 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3318 | }, |
3319 | { | |
1da177e4 LT |
3320 | .procname = "min_pmtu", |
3321 | .data = &ip_rt_min_pmtu, | |
3322 | .maxlen = sizeof(int), | |
3323 | .mode = 0644, | |
6d9f239a | 3324 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3325 | }, |
3326 | { | |
1da177e4 LT |
3327 | .procname = "min_adv_mss", |
3328 | .data = &ip_rt_min_advmss, | |
3329 | .maxlen = sizeof(int), | |
3330 | .mode = 0644, | |
6d9f239a | 3331 | .proc_handler = proc_dointvec, |
1da177e4 | 3332 | }, |
f8572d8f | 3333 | { } |
1da177e4 | 3334 | }; |
39a23e75 | 3335 | |
2f4520d3 AV |
3336 | static struct ctl_table empty[1]; |
3337 | ||
3338 | static struct ctl_table ipv4_skeleton[] = | |
3339 | { | |
f8572d8f | 3340 | { .procname = "route", |
d994af0d | 3341 | .mode = 0555, .child = ipv4_route_table}, |
f8572d8f | 3342 | { .procname = "neigh", |
d994af0d | 3343 | .mode = 0555, .child = empty}, |
2f4520d3 AV |
3344 | { } |
3345 | }; | |
3346 | ||
3347 | static __net_initdata struct ctl_path ipv4_path[] = { | |
f8572d8f EB |
3348 | { .procname = "net", }, |
3349 | { .procname = "ipv4", }, | |
39a23e75 DL |
3350 | { }, |
3351 | }; | |
3352 | ||
39a23e75 DL |
3353 | static struct ctl_table ipv4_route_flush_table[] = { |
3354 | { | |
39a23e75 DL |
3355 | .procname = "flush", |
3356 | .maxlen = sizeof(int), | |
3357 | .mode = 0200, | |
6d9f239a | 3358 | .proc_handler = ipv4_sysctl_rtcache_flush, |
39a23e75 | 3359 | }, |
f8572d8f | 3360 | { }, |
39a23e75 DL |
3361 | }; |
3362 | ||
2f4520d3 | 3363 | static __net_initdata struct ctl_path ipv4_route_path[] = { |
f8572d8f EB |
3364 | { .procname = "net", }, |
3365 | { .procname = "ipv4", }, | |
3366 | { .procname = "route", }, | |
2f4520d3 AV |
3367 | { }, |
3368 | }; | |
3369 | ||
39a23e75 DL |
3370 | static __net_init int sysctl_route_net_init(struct net *net) |
3371 | { | |
3372 | struct ctl_table *tbl; | |
3373 | ||
3374 | tbl = ipv4_route_flush_table; | |
09ad9bc7 | 3375 | if (!net_eq(net, &init_net)) { |
39a23e75 DL |
3376 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); |
3377 | if (tbl == NULL) | |
3378 | goto err_dup; | |
3379 | } | |
3380 | tbl[0].extra1 = net; | |
3381 | ||
3382 | net->ipv4.route_hdr = | |
3383 | register_net_sysctl_table(net, ipv4_route_path, tbl); | |
3384 | if (net->ipv4.route_hdr == NULL) | |
3385 | goto err_reg; | |
3386 | return 0; | |
3387 | ||
3388 | err_reg: | |
3389 | if (tbl != ipv4_route_flush_table) | |
3390 | kfree(tbl); | |
3391 | err_dup: | |
3392 | return -ENOMEM; | |
3393 | } | |
3394 | ||
3395 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
3396 | { | |
3397 | struct ctl_table *tbl; | |
3398 | ||
3399 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
3400 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
3401 | BUG_ON(tbl == ipv4_route_flush_table); | |
3402 | kfree(tbl); | |
3403 | } | |
3404 | ||
3405 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
3406 | .init = sysctl_route_net_init, | |
3407 | .exit = sysctl_route_net_exit, | |
3408 | }; | |
1da177e4 LT |
3409 | #endif |
3410 | ||
3ee94372 | 3411 | static __net_init int rt_genid_init(struct net *net) |
9f5e97e5 | 3412 | { |
3ee94372 NH |
3413 | get_random_bytes(&net->ipv4.rt_genid, |
3414 | sizeof(net->ipv4.rt_genid)); | |
436c3b66 DM |
3415 | get_random_bytes(&net->ipv4.dev_addr_genid, |
3416 | sizeof(net->ipv4.dev_addr_genid)); | |
9f5e97e5 DL |
3417 | return 0; |
3418 | } | |
3419 | ||
3ee94372 NH |
3420 | static __net_initdata struct pernet_operations rt_genid_ops = { |
3421 | .init = rt_genid_init, | |
9f5e97e5 DL |
3422 | }; |
3423 | ||
3424 | ||
c7066f70 | 3425 | #ifdef CONFIG_IP_ROUTE_CLASSID |
7d720c3e | 3426 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; |
c7066f70 | 3427 | #endif /* CONFIG_IP_ROUTE_CLASSID */ |
1da177e4 LT |
3428 | |
3429 | static __initdata unsigned long rhash_entries; | |
3430 | static int __init set_rhash_entries(char *str) | |
3431 | { | |
3432 | if (!str) | |
3433 | return 0; | |
3434 | rhash_entries = simple_strtoul(str, &str, 0); | |
3435 | return 1; | |
3436 | } | |
3437 | __setup("rhash_entries=", set_rhash_entries); | |
3438 | ||
3439 | int __init ip_rt_init(void) | |
3440 | { | |
424c4b70 | 3441 | int rc = 0; |
1da177e4 | 3442 | |
c7066f70 | 3443 | #ifdef CONFIG_IP_ROUTE_CLASSID |
0dcec8c2 | 3444 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); |
1da177e4 LT |
3445 | if (!ip_rt_acct) |
3446 | panic("IP: failed to allocate ip_rt_acct\n"); | |
1da177e4 LT |
3447 | #endif |
3448 | ||
e5d679f3 AD |
3449 | ipv4_dst_ops.kmem_cachep = |
3450 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
20c2df83 | 3451 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 3452 | |
14e50e57 DM |
3453 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; |
3454 | ||
fc66f95c ED |
3455 | if (dst_entries_init(&ipv4_dst_ops) < 0) |
3456 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
3457 | ||
3458 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
3459 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
3460 | ||
424c4b70 ED |
3461 | rt_hash_table = (struct rt_hash_bucket *) |
3462 | alloc_large_system_hash("IP route cache", | |
3463 | sizeof(struct rt_hash_bucket), | |
3464 | rhash_entries, | |
4481374c | 3465 | (totalram_pages >= 128 * 1024) ? |
18955cfc | 3466 | 15 : 17, |
8d1502de | 3467 | 0, |
424c4b70 ED |
3468 | &rt_hash_log, |
3469 | &rt_hash_mask, | |
c9503e0f | 3470 | rhash_entries ? 0 : 512 * 1024); |
22c047cc ED |
3471 | memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket)); |
3472 | rt_hash_lock_init(); | |
1da177e4 LT |
3473 | |
3474 | ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1); | |
3475 | ip_rt_max_size = (rt_hash_mask + 1) * 16; | |
3476 | ||
1da177e4 LT |
3477 | devinet_init(); |
3478 | ip_fib_init(); | |
3479 | ||
9f28a2fc ED |
3480 | INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func); |
3481 | expires_ljiffies = jiffies; | |
3482 | schedule_delayed_work(&expires_work, | |
3483 | net_random() % ip_rt_gc_interval + ip_rt_gc_interval); | |
3484 | ||
73b38711 | 3485 | if (ip_rt_proc_init()) |
058bd4d2 | 3486 | pr_err("Unable to create route proc files\n"); |
1da177e4 LT |
3487 | #ifdef CONFIG_XFRM |
3488 | xfrm_init(); | |
a33bc5c1 | 3489 | xfrm4_init(ip_rt_max_size); |
1da177e4 | 3490 | #endif |
c7ac8679 | 3491 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL); |
63f3444f | 3492 | |
39a23e75 DL |
3493 | #ifdef CONFIG_SYSCTL |
3494 | register_pernet_subsys(&sysctl_route_ops); | |
3495 | #endif | |
3ee94372 | 3496 | register_pernet_subsys(&rt_genid_ops); |
1da177e4 LT |
3497 | return rc; |
3498 | } | |
3499 | ||
a1bc6eb4 | 3500 | #ifdef CONFIG_SYSCTL |
eeb61f71 AV |
3501 | /* |
3502 | * We really need to sanitize the damn ipv4 init order, then all | |
3503 | * this nonsense will go away. | |
3504 | */ | |
3505 | void __init ip_static_sysctl_init(void) | |
3506 | { | |
2f4520d3 | 3507 | register_sysctl_paths(ipv4_path, ipv4_skeleton); |
eeb61f71 | 3508 | } |
a1bc6eb4 | 3509 | #endif |