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 | ||
afd46503 JP |
65 | #define pr_fmt(fmt) "IPv4: " fmt |
66 | ||
1da177e4 LT |
67 | #include <linux/module.h> |
68 | #include <asm/uaccess.h> | |
1da177e4 LT |
69 | #include <linux/bitops.h> |
70 | #include <linux/types.h> | |
71 | #include <linux/kernel.h> | |
1da177e4 | 72 | #include <linux/mm.h> |
424c4b70 | 73 | #include <linux/bootmem.h> |
1da177e4 LT |
74 | #include <linux/string.h> |
75 | #include <linux/socket.h> | |
76 | #include <linux/sockios.h> | |
77 | #include <linux/errno.h> | |
78 | #include <linux/in.h> | |
79 | #include <linux/inet.h> | |
80 | #include <linux/netdevice.h> | |
81 | #include <linux/proc_fs.h> | |
82 | #include <linux/init.h> | |
39c90ece | 83 | #include <linux/workqueue.h> |
1da177e4 | 84 | #include <linux/skbuff.h> |
1da177e4 LT |
85 | #include <linux/inetdevice.h> |
86 | #include <linux/igmp.h> | |
87 | #include <linux/pkt_sched.h> | |
88 | #include <linux/mroute.h> | |
89 | #include <linux/netfilter_ipv4.h> | |
90 | #include <linux/random.h> | |
91 | #include <linux/jhash.h> | |
92 | #include <linux/rcupdate.h> | |
93 | #include <linux/times.h> | |
5a0e3ad6 | 94 | #include <linux/slab.h> |
b9eda06f | 95 | #include <linux/prefetch.h> |
352e512c | 96 | #include <net/dst.h> |
457c4cbc | 97 | #include <net/net_namespace.h> |
1da177e4 LT |
98 | #include <net/protocol.h> |
99 | #include <net/ip.h> | |
100 | #include <net/route.h> | |
101 | #include <net/inetpeer.h> | |
102 | #include <net/sock.h> | |
103 | #include <net/ip_fib.h> | |
104 | #include <net/arp.h> | |
105 | #include <net/tcp.h> | |
106 | #include <net/icmp.h> | |
107 | #include <net/xfrm.h> | |
8d71740c | 108 | #include <net/netevent.h> |
63f3444f | 109 | #include <net/rtnetlink.h> |
1da177e4 LT |
110 | #ifdef CONFIG_SYSCTL |
111 | #include <linux/sysctl.h> | |
112 | #endif | |
6e5714ea | 113 | #include <net/secure_seq.h> |
1da177e4 | 114 | |
68a5e3dd | 115 | #define RT_FL_TOS(oldflp4) \ |
f61759e6 | 116 | ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) |
1da177e4 LT |
117 | |
118 | #define IP_MAX_MTU 0xFFF0 | |
119 | ||
120 | #define RT_GC_TIMEOUT (300*HZ) | |
121 | ||
1da177e4 | 122 | static int ip_rt_max_size; |
817bc4db | 123 | static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; |
9f28a2fc | 124 | static int ip_rt_gc_interval __read_mostly = 60 * HZ; |
817bc4db SH |
125 | static int ip_rt_gc_min_interval __read_mostly = HZ / 2; |
126 | static int ip_rt_redirect_number __read_mostly = 9; | |
127 | static int ip_rt_redirect_load __read_mostly = HZ / 50; | |
128 | static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); | |
129 | static int ip_rt_error_cost __read_mostly = HZ; | |
130 | static int ip_rt_error_burst __read_mostly = 5 * HZ; | |
131 | static int ip_rt_gc_elasticity __read_mostly = 8; | |
132 | static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; | |
133 | static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; | |
134 | static int ip_rt_min_advmss __read_mostly = 256; | |
1080d709 | 135 | static int rt_chain_length_max __read_mostly = 20; |
1da177e4 | 136 | |
9f28a2fc ED |
137 | static struct delayed_work expires_work; |
138 | static unsigned long expires_ljiffies; | |
139 | ||
1da177e4 LT |
140 | /* |
141 | * Interface to generic destination cache. | |
142 | */ | |
143 | ||
144 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
0dbaee3b | 145 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst); |
ebb762f2 | 146 | static unsigned int ipv4_mtu(const struct dst_entry *dst); |
1da177e4 | 147 | static void ipv4_dst_destroy(struct dst_entry *dst); |
1da177e4 LT |
148 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); |
149 | static void ipv4_link_failure(struct sk_buff *skb); | |
150 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu); | |
569d3645 | 151 | static int rt_garbage_collect(struct dst_ops *ops); |
1da177e4 | 152 | |
72cdd1d9 ED |
153 | static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, |
154 | int how) | |
155 | { | |
156 | } | |
1da177e4 | 157 | |
62fa8a84 DM |
158 | static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) |
159 | { | |
06582540 DM |
160 | struct rtable *rt = (struct rtable *) dst; |
161 | struct inet_peer *peer; | |
162 | u32 *p = NULL; | |
163 | ||
164 | if (!rt->peer) | |
a48eff12 | 165 | rt_bind_peer(rt, rt->rt_dst, 1); |
62fa8a84 | 166 | |
06582540 DM |
167 | peer = rt->peer; |
168 | if (peer) { | |
62fa8a84 DM |
169 | u32 *old_p = __DST_METRICS_PTR(old); |
170 | unsigned long prev, new; | |
171 | ||
06582540 DM |
172 | p = peer->metrics; |
173 | if (inet_metrics_new(peer)) | |
174 | memcpy(p, old_p, sizeof(u32) * RTAX_MAX); | |
62fa8a84 DM |
175 | |
176 | new = (unsigned long) p; | |
177 | prev = cmpxchg(&dst->_metrics, old, new); | |
178 | ||
179 | if (prev != old) { | |
62fa8a84 DM |
180 | p = __DST_METRICS_PTR(prev); |
181 | if (prev & DST_METRICS_READ_ONLY) | |
182 | p = NULL; | |
183 | } else { | |
62fa8a84 DM |
184 | if (rt->fi) { |
185 | fib_info_put(rt->fi); | |
186 | rt->fi = NULL; | |
187 | } | |
188 | } | |
189 | } | |
190 | return p; | |
191 | } | |
192 | ||
d3aaeb38 DM |
193 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr); |
194 | ||
1da177e4 LT |
195 | static struct dst_ops ipv4_dst_ops = { |
196 | .family = AF_INET, | |
09640e63 | 197 | .protocol = cpu_to_be16(ETH_P_IP), |
1da177e4 LT |
198 | .gc = rt_garbage_collect, |
199 | .check = ipv4_dst_check, | |
0dbaee3b | 200 | .default_advmss = ipv4_default_advmss, |
ebb762f2 | 201 | .mtu = ipv4_mtu, |
62fa8a84 | 202 | .cow_metrics = ipv4_cow_metrics, |
1da177e4 LT |
203 | .destroy = ipv4_dst_destroy, |
204 | .ifdown = ipv4_dst_ifdown, | |
205 | .negative_advice = ipv4_negative_advice, | |
206 | .link_failure = ipv4_link_failure, | |
207 | .update_pmtu = ip_rt_update_pmtu, | |
1ac06e03 | 208 | .local_out = __ip_local_out, |
d3aaeb38 | 209 | .neigh_lookup = ipv4_neigh_lookup, |
1da177e4 LT |
210 | }; |
211 | ||
212 | #define ECN_OR_COST(class) TC_PRIO_##class | |
213 | ||
4839c52b | 214 | const __u8 ip_tos2prio[16] = { |
1da177e4 | 215 | TC_PRIO_BESTEFFORT, |
4a2b9c37 | 216 | ECN_OR_COST(BESTEFFORT), |
1da177e4 LT |
217 | TC_PRIO_BESTEFFORT, |
218 | ECN_OR_COST(BESTEFFORT), | |
219 | TC_PRIO_BULK, | |
220 | ECN_OR_COST(BULK), | |
221 | TC_PRIO_BULK, | |
222 | ECN_OR_COST(BULK), | |
223 | TC_PRIO_INTERACTIVE, | |
224 | ECN_OR_COST(INTERACTIVE), | |
225 | TC_PRIO_INTERACTIVE, | |
226 | ECN_OR_COST(INTERACTIVE), | |
227 | TC_PRIO_INTERACTIVE_BULK, | |
228 | ECN_OR_COST(INTERACTIVE_BULK), | |
229 | TC_PRIO_INTERACTIVE_BULK, | |
230 | ECN_OR_COST(INTERACTIVE_BULK) | |
231 | }; | |
d4a96865 | 232 | EXPORT_SYMBOL(ip_tos2prio); |
1da177e4 LT |
233 | |
234 | /* | |
235 | * Route cache. | |
236 | */ | |
237 | ||
238 | /* The locking scheme is rather straight forward: | |
239 | * | |
240 | * 1) Read-Copy Update protects the buckets of the central route hash. | |
241 | * 2) Only writers remove entries, and they hold the lock | |
242 | * as they look at rtable reference counts. | |
243 | * 3) Only readers acquire references to rtable entries, | |
244 | * they do so with atomic increments and with the | |
245 | * lock held. | |
246 | */ | |
247 | ||
248 | struct rt_hash_bucket { | |
1c31720a | 249 | struct rtable __rcu *chain; |
22c047cc | 250 | }; |
1080d709 | 251 | |
8a25d5de IM |
252 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ |
253 | defined(CONFIG_PROVE_LOCKING) | |
22c047cc ED |
254 | /* |
255 | * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks | |
256 | * The size of this table is a power of two and depends on the number of CPUS. | |
62051200 | 257 | * (on lockdep we have a quite big spinlock_t, so keep the size down there) |
22c047cc | 258 | */ |
62051200 IM |
259 | #ifdef CONFIG_LOCKDEP |
260 | # define RT_HASH_LOCK_SZ 256 | |
22c047cc | 261 | #else |
62051200 IM |
262 | # if NR_CPUS >= 32 |
263 | # define RT_HASH_LOCK_SZ 4096 | |
264 | # elif NR_CPUS >= 16 | |
265 | # define RT_HASH_LOCK_SZ 2048 | |
266 | # elif NR_CPUS >= 8 | |
267 | # define RT_HASH_LOCK_SZ 1024 | |
268 | # elif NR_CPUS >= 4 | |
269 | # define RT_HASH_LOCK_SZ 512 | |
270 | # else | |
271 | # define RT_HASH_LOCK_SZ 256 | |
272 | # endif | |
22c047cc ED |
273 | #endif |
274 | ||
275 | static spinlock_t *rt_hash_locks; | |
276 | # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)] | |
1ff1cc20 PE |
277 | |
278 | static __init void rt_hash_lock_init(void) | |
279 | { | |
280 | int i; | |
281 | ||
282 | rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ, | |
283 | GFP_KERNEL); | |
284 | if (!rt_hash_locks) | |
285 | panic("IP: failed to allocate rt_hash_locks\n"); | |
286 | ||
287 | for (i = 0; i < RT_HASH_LOCK_SZ; i++) | |
288 | spin_lock_init(&rt_hash_locks[i]); | |
289 | } | |
22c047cc ED |
290 | #else |
291 | # define rt_hash_lock_addr(slot) NULL | |
1ff1cc20 PE |
292 | |
293 | static inline void rt_hash_lock_init(void) | |
294 | { | |
295 | } | |
22c047cc | 296 | #endif |
1da177e4 | 297 | |
817bc4db | 298 | static struct rt_hash_bucket *rt_hash_table __read_mostly; |
95c96174 | 299 | static unsigned int rt_hash_mask __read_mostly; |
817bc4db | 300 | static unsigned int rt_hash_log __read_mostly; |
1da177e4 | 301 | |
2f970d83 | 302 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); |
27f39c73 | 303 | #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field) |
1da177e4 | 304 | |
b00180de | 305 | static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx, |
0eae88f3 | 306 | int genid) |
1da177e4 | 307 | { |
0eae88f3 | 308 | return jhash_3words((__force u32)daddr, (__force u32)saddr, |
b00180de | 309 | idx, genid) |
29e75252 | 310 | & rt_hash_mask; |
1da177e4 LT |
311 | } |
312 | ||
e84f84f2 DL |
313 | static inline int rt_genid(struct net *net) |
314 | { | |
315 | return atomic_read(&net->ipv4.rt_genid); | |
316 | } | |
317 | ||
1da177e4 LT |
318 | #ifdef CONFIG_PROC_FS |
319 | struct rt_cache_iter_state { | |
a75e936f | 320 | struct seq_net_private p; |
1da177e4 | 321 | int bucket; |
29e75252 | 322 | int genid; |
1da177e4 LT |
323 | }; |
324 | ||
1218854a | 325 | static struct rtable *rt_cache_get_first(struct seq_file *seq) |
1da177e4 | 326 | { |
1218854a | 327 | struct rt_cache_iter_state *st = seq->private; |
1da177e4 | 328 | struct rtable *r = NULL; |
1da177e4 LT |
329 | |
330 | for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) { | |
33d480ce | 331 | if (!rcu_access_pointer(rt_hash_table[st->bucket].chain)) |
a6272665 | 332 | continue; |
1da177e4 | 333 | rcu_read_lock_bh(); |
a898def2 | 334 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
29e75252 | 335 | while (r) { |
d8d1f30b | 336 | if (dev_net(r->dst.dev) == seq_file_net(seq) && |
a75e936f | 337 | r->rt_genid == st->genid) |
29e75252 | 338 | return r; |
d8d1f30b | 339 | r = rcu_dereference_bh(r->dst.rt_next); |
29e75252 | 340 | } |
1da177e4 LT |
341 | rcu_read_unlock_bh(); |
342 | } | |
29e75252 | 343 | return r; |
1da177e4 LT |
344 | } |
345 | ||
1218854a | 346 | static struct rtable *__rt_cache_get_next(struct seq_file *seq, |
642d6318 | 347 | struct rtable *r) |
1da177e4 | 348 | { |
1218854a | 349 | struct rt_cache_iter_state *st = seq->private; |
a6272665 | 350 | |
1c31720a | 351 | r = rcu_dereference_bh(r->dst.rt_next); |
1da177e4 LT |
352 | while (!r) { |
353 | rcu_read_unlock_bh(); | |
a6272665 ED |
354 | do { |
355 | if (--st->bucket < 0) | |
356 | return NULL; | |
33d480ce | 357 | } while (!rcu_access_pointer(rt_hash_table[st->bucket].chain)); |
1da177e4 | 358 | rcu_read_lock_bh(); |
1c31720a | 359 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
1da177e4 | 360 | } |
1c31720a | 361 | return r; |
1da177e4 LT |
362 | } |
363 | ||
1218854a | 364 | static struct rtable *rt_cache_get_next(struct seq_file *seq, |
642d6318 DL |
365 | struct rtable *r) |
366 | { | |
1218854a YH |
367 | struct rt_cache_iter_state *st = seq->private; |
368 | while ((r = __rt_cache_get_next(seq, r)) != NULL) { | |
d8d1f30b | 369 | if (dev_net(r->dst.dev) != seq_file_net(seq)) |
a75e936f | 370 | continue; |
642d6318 DL |
371 | if (r->rt_genid == st->genid) |
372 | break; | |
373 | } | |
374 | return r; | |
375 | } | |
376 | ||
1218854a | 377 | static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 378 | { |
1218854a | 379 | struct rtable *r = rt_cache_get_first(seq); |
1da177e4 LT |
380 | |
381 | if (r) | |
1218854a | 382 | while (pos && (r = rt_cache_get_next(seq, r))) |
1da177e4 LT |
383 | --pos; |
384 | return pos ? NULL : r; | |
385 | } | |
386 | ||
387 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) | |
388 | { | |
29e75252 | 389 | struct rt_cache_iter_state *st = seq->private; |
29e75252 | 390 | if (*pos) |
1218854a | 391 | return rt_cache_get_idx(seq, *pos - 1); |
e84f84f2 | 392 | st->genid = rt_genid(seq_file_net(seq)); |
29e75252 | 393 | return SEQ_START_TOKEN; |
1da177e4 LT |
394 | } |
395 | ||
396 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
397 | { | |
29e75252 | 398 | struct rtable *r; |
1da177e4 LT |
399 | |
400 | if (v == SEQ_START_TOKEN) | |
1218854a | 401 | r = rt_cache_get_first(seq); |
1da177e4 | 402 | else |
1218854a | 403 | r = rt_cache_get_next(seq, v); |
1da177e4 LT |
404 | ++*pos; |
405 | return r; | |
406 | } | |
407 | ||
408 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
409 | { | |
410 | if (v && v != SEQ_START_TOKEN) | |
411 | rcu_read_unlock_bh(); | |
412 | } | |
413 | ||
414 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
415 | { | |
416 | if (v == SEQ_START_TOKEN) | |
417 | seq_printf(seq, "%-127s\n", | |
418 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
419 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
420 | "HHUptod\tSpecDst"); | |
421 | else { | |
422 | struct rtable *r = v; | |
69cce1d1 | 423 | struct neighbour *n; |
218fa90f | 424 | int len, HHUptod; |
1da177e4 | 425 | |
218fa90f | 426 | rcu_read_lock(); |
27217455 | 427 | n = dst_get_neighbour_noref(&r->dst); |
218fa90f ED |
428 | HHUptod = (n && (n->nud_state & NUD_CONNECTED)) ? 1 : 0; |
429 | rcu_read_unlock(); | |
430 | ||
0eae88f3 ED |
431 | seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t" |
432 | "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n", | |
d8d1f30b | 433 | r->dst.dev ? r->dst.dev->name : "*", |
0eae88f3 ED |
434 | (__force u32)r->rt_dst, |
435 | (__force u32)r->rt_gateway, | |
d8d1f30b CG |
436 | r->rt_flags, atomic_read(&r->dst.__refcnt), |
437 | r->dst.__use, 0, (__force u32)r->rt_src, | |
0dbaee3b | 438 | dst_metric_advmss(&r->dst) + 40, |
d8d1f30b CG |
439 | dst_metric(&r->dst, RTAX_WINDOW), |
440 | (int)((dst_metric(&r->dst, RTAX_RTT) >> 3) + | |
441 | dst_metric(&r->dst, RTAX_RTTVAR)), | |
475949d8 | 442 | r->rt_key_tos, |
f6b72b62 | 443 | -1, |
218fa90f | 444 | HHUptod, |
5e659e4c PE |
445 | r->rt_spec_dst, &len); |
446 | ||
447 | seq_printf(seq, "%*s\n", 127 - len, ""); | |
e905a9ed YH |
448 | } |
449 | return 0; | |
1da177e4 LT |
450 | } |
451 | ||
f690808e | 452 | static const struct seq_operations rt_cache_seq_ops = { |
1da177e4 LT |
453 | .start = rt_cache_seq_start, |
454 | .next = rt_cache_seq_next, | |
455 | .stop = rt_cache_seq_stop, | |
456 | .show = rt_cache_seq_show, | |
457 | }; | |
458 | ||
459 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
460 | { | |
a75e936f | 461 | return seq_open_net(inode, file, &rt_cache_seq_ops, |
cf7732e4 | 462 | sizeof(struct rt_cache_iter_state)); |
1da177e4 LT |
463 | } |
464 | ||
9a32144e | 465 | static const struct file_operations rt_cache_seq_fops = { |
1da177e4 LT |
466 | .owner = THIS_MODULE, |
467 | .open = rt_cache_seq_open, | |
468 | .read = seq_read, | |
469 | .llseek = seq_lseek, | |
a75e936f | 470 | .release = seq_release_net, |
1da177e4 LT |
471 | }; |
472 | ||
473 | ||
474 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
475 | { | |
476 | int cpu; | |
477 | ||
478 | if (*pos == 0) | |
479 | return SEQ_START_TOKEN; | |
480 | ||
0f23174a | 481 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
482 | if (!cpu_possible(cpu)) |
483 | continue; | |
484 | *pos = cpu+1; | |
2f970d83 | 485 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
486 | } |
487 | return NULL; | |
488 | } | |
489 | ||
490 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
491 | { | |
492 | int cpu; | |
493 | ||
0f23174a | 494 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
495 | if (!cpu_possible(cpu)) |
496 | continue; | |
497 | *pos = cpu+1; | |
2f970d83 | 498 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
499 | } |
500 | return NULL; | |
e905a9ed | 501 | |
1da177e4 LT |
502 | } |
503 | ||
504 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
505 | { | |
506 | ||
507 | } | |
508 | ||
509 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
510 | { | |
511 | struct rt_cache_stat *st = v; | |
512 | ||
513 | if (v == SEQ_START_TOKEN) { | |
5bec0039 | 514 | 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 |
515 | return 0; |
516 | } | |
e905a9ed | 517 | |
1da177e4 LT |
518 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " |
519 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
fc66f95c | 520 | dst_entries_get_slow(&ipv4_dst_ops), |
1da177e4 LT |
521 | st->in_hit, |
522 | st->in_slow_tot, | |
523 | st->in_slow_mc, | |
524 | st->in_no_route, | |
525 | st->in_brd, | |
526 | st->in_martian_dst, | |
527 | st->in_martian_src, | |
528 | ||
529 | st->out_hit, | |
530 | st->out_slow_tot, | |
e905a9ed | 531 | st->out_slow_mc, |
1da177e4 LT |
532 | |
533 | st->gc_total, | |
534 | st->gc_ignored, | |
535 | st->gc_goal_miss, | |
536 | st->gc_dst_overflow, | |
537 | st->in_hlist_search, | |
538 | st->out_hlist_search | |
539 | ); | |
540 | return 0; | |
541 | } | |
542 | ||
f690808e | 543 | static const struct seq_operations rt_cpu_seq_ops = { |
1da177e4 LT |
544 | .start = rt_cpu_seq_start, |
545 | .next = rt_cpu_seq_next, | |
546 | .stop = rt_cpu_seq_stop, | |
547 | .show = rt_cpu_seq_show, | |
548 | }; | |
549 | ||
550 | ||
551 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
552 | { | |
553 | return seq_open(file, &rt_cpu_seq_ops); | |
554 | } | |
555 | ||
9a32144e | 556 | static const struct file_operations rt_cpu_seq_fops = { |
1da177e4 LT |
557 | .owner = THIS_MODULE, |
558 | .open = rt_cpu_seq_open, | |
559 | .read = seq_read, | |
560 | .llseek = seq_lseek, | |
561 | .release = seq_release, | |
562 | }; | |
563 | ||
c7066f70 | 564 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 565 | static int rt_acct_proc_show(struct seq_file *m, void *v) |
78c686e9 | 566 | { |
a661c419 AD |
567 | struct ip_rt_acct *dst, *src; |
568 | unsigned int i, j; | |
569 | ||
570 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
571 | if (!dst) | |
572 | return -ENOMEM; | |
573 | ||
574 | for_each_possible_cpu(i) { | |
575 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
576 | for (j = 0; j < 256; j++) { | |
577 | dst[j].o_bytes += src[j].o_bytes; | |
578 | dst[j].o_packets += src[j].o_packets; | |
579 | dst[j].i_bytes += src[j].i_bytes; | |
580 | dst[j].i_packets += src[j].i_packets; | |
581 | } | |
78c686e9 PE |
582 | } |
583 | ||
a661c419 AD |
584 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); |
585 | kfree(dst); | |
586 | return 0; | |
587 | } | |
78c686e9 | 588 | |
a661c419 AD |
589 | static int rt_acct_proc_open(struct inode *inode, struct file *file) |
590 | { | |
591 | return single_open(file, rt_acct_proc_show, NULL); | |
78c686e9 | 592 | } |
a661c419 AD |
593 | |
594 | static const struct file_operations rt_acct_proc_fops = { | |
595 | .owner = THIS_MODULE, | |
596 | .open = rt_acct_proc_open, | |
597 | .read = seq_read, | |
598 | .llseek = seq_lseek, | |
599 | .release = single_release, | |
600 | }; | |
78c686e9 | 601 | #endif |
107f1634 | 602 | |
73b38711 | 603 | static int __net_init ip_rt_do_proc_init(struct net *net) |
107f1634 PE |
604 | { |
605 | struct proc_dir_entry *pde; | |
606 | ||
607 | pde = proc_net_fops_create(net, "rt_cache", S_IRUGO, | |
608 | &rt_cache_seq_fops); | |
609 | if (!pde) | |
610 | goto err1; | |
611 | ||
77020720 WC |
612 | pde = proc_create("rt_cache", S_IRUGO, |
613 | net->proc_net_stat, &rt_cpu_seq_fops); | |
107f1634 PE |
614 | if (!pde) |
615 | goto err2; | |
616 | ||
c7066f70 | 617 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 618 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); |
107f1634 PE |
619 | if (!pde) |
620 | goto err3; | |
621 | #endif | |
622 | return 0; | |
623 | ||
c7066f70 | 624 | #ifdef CONFIG_IP_ROUTE_CLASSID |
107f1634 PE |
625 | err3: |
626 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
627 | #endif | |
628 | err2: | |
629 | remove_proc_entry("rt_cache", net->proc_net); | |
630 | err1: | |
631 | return -ENOMEM; | |
632 | } | |
73b38711 DL |
633 | |
634 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
635 | { | |
636 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
637 | remove_proc_entry("rt_cache", net->proc_net); | |
c7066f70 | 638 | #ifdef CONFIG_IP_ROUTE_CLASSID |
73b38711 | 639 | remove_proc_entry("rt_acct", net->proc_net); |
0a931acf | 640 | #endif |
73b38711 DL |
641 | } |
642 | ||
643 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
644 | .init = ip_rt_do_proc_init, | |
645 | .exit = ip_rt_do_proc_exit, | |
646 | }; | |
647 | ||
648 | static int __init ip_rt_proc_init(void) | |
649 | { | |
650 | return register_pernet_subsys(&ip_rt_proc_ops); | |
651 | } | |
652 | ||
107f1634 | 653 | #else |
73b38711 | 654 | static inline int ip_rt_proc_init(void) |
107f1634 PE |
655 | { |
656 | return 0; | |
657 | } | |
1da177e4 | 658 | #endif /* CONFIG_PROC_FS */ |
e905a9ed | 659 | |
5969f71d | 660 | static inline void rt_free(struct rtable *rt) |
1da177e4 | 661 | { |
d8d1f30b | 662 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
663 | } |
664 | ||
5969f71d | 665 | static inline void rt_drop(struct rtable *rt) |
1da177e4 | 666 | { |
1da177e4 | 667 | ip_rt_put(rt); |
d8d1f30b | 668 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
669 | } |
670 | ||
5969f71d | 671 | static inline int rt_fast_clean(struct rtable *rth) |
1da177e4 LT |
672 | { |
673 | /* Kill broadcast/multicast entries very aggresively, if they | |
674 | collide in hash table with more useful entries */ | |
675 | return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) && | |
c7537967 | 676 | rt_is_input_route(rth) && rth->dst.rt_next; |
1da177e4 LT |
677 | } |
678 | ||
5969f71d | 679 | static inline int rt_valuable(struct rtable *rth) |
1da177e4 LT |
680 | { |
681 | return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || | |
2c8cec5c | 682 | (rth->peer && rth->peer->pmtu_expires); |
1da177e4 LT |
683 | } |
684 | ||
685 | static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) | |
686 | { | |
687 | unsigned long age; | |
688 | int ret = 0; | |
689 | ||
d8d1f30b | 690 | if (atomic_read(&rth->dst.__refcnt)) |
1da177e4 LT |
691 | goto out; |
692 | ||
d8d1f30b | 693 | age = jiffies - rth->dst.lastuse; |
1da177e4 LT |
694 | if ((age <= tmo1 && !rt_fast_clean(rth)) || |
695 | (age <= tmo2 && rt_valuable(rth))) | |
696 | goto out; | |
697 | ret = 1; | |
698 | out: return ret; | |
699 | } | |
700 | ||
701 | /* Bits of score are: | |
702 | * 31: very valuable | |
703 | * 30: not quite useless | |
704 | * 29..0: usage counter | |
705 | */ | |
706 | static inline u32 rt_score(struct rtable *rt) | |
707 | { | |
d8d1f30b | 708 | u32 score = jiffies - rt->dst.lastuse; |
1da177e4 LT |
709 | |
710 | score = ~score & ~(3<<30); | |
711 | ||
712 | if (rt_valuable(rt)) | |
713 | score |= (1<<31); | |
714 | ||
c7537967 | 715 | if (rt_is_output_route(rt) || |
1da177e4 LT |
716 | !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL))) |
717 | score |= (1<<30); | |
718 | ||
719 | return score; | |
720 | } | |
721 | ||
1080d709 NH |
722 | static inline bool rt_caching(const struct net *net) |
723 | { | |
724 | return net->ipv4.current_rt_cache_rebuild_count <= | |
725 | net->ipv4.sysctl_rt_cache_rebuild_count; | |
726 | } | |
727 | ||
5e2b61f7 DM |
728 | static inline bool compare_hash_inputs(const struct rtable *rt1, |
729 | const struct rtable *rt2) | |
1080d709 | 730 | { |
5e2b61f7 DM |
731 | return ((((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
732 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
97a80410 | 733 | (rt1->rt_route_iif ^ rt2->rt_route_iif)) == 0); |
1080d709 NH |
734 | } |
735 | ||
5e2b61f7 | 736 | static inline int compare_keys(struct rtable *rt1, struct rtable *rt2) |
1da177e4 | 737 | { |
5e2b61f7 DM |
738 | return (((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
739 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
740 | (rt1->rt_mark ^ rt2->rt_mark) | | |
475949d8 | 741 | (rt1->rt_key_tos ^ rt2->rt_key_tos) | |
d547f727 | 742 | (rt1->rt_route_iif ^ rt2->rt_route_iif) | |
97a80410 | 743 | (rt1->rt_oif ^ rt2->rt_oif)) == 0; |
1da177e4 LT |
744 | } |
745 | ||
b5921910 DL |
746 | static inline int compare_netns(struct rtable *rt1, struct rtable *rt2) |
747 | { | |
d8d1f30b | 748 | return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev)); |
b5921910 DL |
749 | } |
750 | ||
e84f84f2 DL |
751 | static inline int rt_is_expired(struct rtable *rth) |
752 | { | |
d8d1f30b | 753 | return rth->rt_genid != rt_genid(dev_net(rth->dst.dev)); |
e84f84f2 DL |
754 | } |
755 | ||
beb659bd ED |
756 | /* |
757 | * Perform a full scan of hash table and free all entries. | |
758 | * Can be called by a softirq or a process. | |
759 | * In the later case, we want to be reschedule if necessary | |
760 | */ | |
6561a3b1 | 761 | static void rt_do_flush(struct net *net, int process_context) |
beb659bd ED |
762 | { |
763 | unsigned int i; | |
764 | struct rtable *rth, *next; | |
765 | ||
766 | for (i = 0; i <= rt_hash_mask; i++) { | |
6561a3b1 DM |
767 | struct rtable __rcu **pprev; |
768 | struct rtable *list; | |
769 | ||
beb659bd ED |
770 | if (process_context && need_resched()) |
771 | cond_resched(); | |
33d480ce | 772 | rth = rcu_access_pointer(rt_hash_table[i].chain); |
beb659bd ED |
773 | if (!rth) |
774 | continue; | |
775 | ||
776 | spin_lock_bh(rt_hash_lock_addr(i)); | |
32cb5b4e | 777 | |
6561a3b1 DM |
778 | list = NULL; |
779 | pprev = &rt_hash_table[i].chain; | |
780 | rth = rcu_dereference_protected(*pprev, | |
1c31720a | 781 | lockdep_is_held(rt_hash_lock_addr(i))); |
32cb5b4e | 782 | |
6561a3b1 DM |
783 | while (rth) { |
784 | next = rcu_dereference_protected(rth->dst.rt_next, | |
1c31720a | 785 | lockdep_is_held(rt_hash_lock_addr(i))); |
6561a3b1 DM |
786 | |
787 | if (!net || | |
788 | net_eq(dev_net(rth->dst.dev), net)) { | |
789 | rcu_assign_pointer(*pprev, next); | |
790 | rcu_assign_pointer(rth->dst.rt_next, list); | |
791 | list = rth; | |
32cb5b4e | 792 | } else { |
6561a3b1 | 793 | pprev = &rth->dst.rt_next; |
32cb5b4e | 794 | } |
6561a3b1 | 795 | rth = next; |
32cb5b4e | 796 | } |
6561a3b1 | 797 | |
beb659bd ED |
798 | spin_unlock_bh(rt_hash_lock_addr(i)); |
799 | ||
6561a3b1 DM |
800 | for (; list; list = next) { |
801 | next = rcu_dereference_protected(list->dst.rt_next, 1); | |
802 | rt_free(list); | |
beb659bd ED |
803 | } |
804 | } | |
805 | } | |
806 | ||
1080d709 NH |
807 | /* |
808 | * While freeing expired entries, we compute average chain length | |
809 | * and standard deviation, using fixed-point arithmetic. | |
810 | * This to have an estimation of rt_chain_length_max | |
811 | * rt_chain_length_max = max(elasticity, AVG + 4*SD) | |
812 | * We use 3 bits for frational part, and 29 (or 61) for magnitude. | |
813 | */ | |
814 | ||
815 | #define FRACT_BITS 3 | |
816 | #define ONE (1UL << FRACT_BITS) | |
817 | ||
98376387 ED |
818 | /* |
819 | * Given a hash chain and an item in this hash chain, | |
820 | * find if a previous entry has the same hash_inputs | |
821 | * (but differs on tos, mark or oif) | |
822 | * Returns 0 if an alias is found. | |
823 | * Returns ONE if rth has no alias before itself. | |
824 | */ | |
825 | static int has_noalias(const struct rtable *head, const struct rtable *rth) | |
826 | { | |
827 | const struct rtable *aux = head; | |
828 | ||
829 | while (aux != rth) { | |
5e2b61f7 | 830 | if (compare_hash_inputs(aux, rth)) |
98376387 | 831 | return 0; |
1c31720a | 832 | aux = rcu_dereference_protected(aux->dst.rt_next, 1); |
98376387 ED |
833 | } |
834 | return ONE; | |
835 | } | |
836 | ||
9f28a2fc ED |
837 | static void rt_check_expire(void) |
838 | { | |
839 | static unsigned int rover; | |
840 | unsigned int i = rover, goal; | |
841 | struct rtable *rth; | |
842 | struct rtable __rcu **rthp; | |
843 | unsigned long samples = 0; | |
844 | unsigned long sum = 0, sum2 = 0; | |
845 | unsigned long delta; | |
846 | u64 mult; | |
847 | ||
848 | delta = jiffies - expires_ljiffies; | |
849 | expires_ljiffies = jiffies; | |
850 | mult = ((u64)delta) << rt_hash_log; | |
851 | if (ip_rt_gc_timeout > 1) | |
852 | do_div(mult, ip_rt_gc_timeout); | |
853 | goal = (unsigned int)mult; | |
854 | if (goal > rt_hash_mask) | |
855 | goal = rt_hash_mask + 1; | |
856 | for (; goal > 0; goal--) { | |
857 | unsigned long tmo = ip_rt_gc_timeout; | |
858 | unsigned long length; | |
859 | ||
860 | i = (i + 1) & rt_hash_mask; | |
861 | rthp = &rt_hash_table[i].chain; | |
862 | ||
863 | if (need_resched()) | |
864 | cond_resched(); | |
865 | ||
866 | samples++; | |
867 | ||
868 | if (rcu_dereference_raw(*rthp) == NULL) | |
869 | continue; | |
870 | length = 0; | |
871 | spin_lock_bh(rt_hash_lock_addr(i)); | |
872 | while ((rth = rcu_dereference_protected(*rthp, | |
873 | lockdep_is_held(rt_hash_lock_addr(i)))) != NULL) { | |
874 | prefetch(rth->dst.rt_next); | |
875 | if (rt_is_expired(rth)) { | |
876 | *rthp = rth->dst.rt_next; | |
877 | rt_free(rth); | |
878 | continue; | |
879 | } | |
880 | if (rth->dst.expires) { | |
881 | /* Entry is expired even if it is in use */ | |
882 | if (time_before_eq(jiffies, rth->dst.expires)) { | |
883 | nofree: | |
884 | tmo >>= 1; | |
885 | rthp = &rth->dst.rt_next; | |
886 | /* | |
887 | * We only count entries on | |
888 | * a chain with equal hash inputs once | |
889 | * so that entries for different QOS | |
890 | * levels, and other non-hash input | |
891 | * attributes don't unfairly skew | |
892 | * the length computation | |
893 | */ | |
894 | length += has_noalias(rt_hash_table[i].chain, rth); | |
895 | continue; | |
896 | } | |
897 | } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) | |
898 | goto nofree; | |
899 | ||
900 | /* Cleanup aged off entries. */ | |
901 | *rthp = rth->dst.rt_next; | |
902 | rt_free(rth); | |
903 | } | |
904 | spin_unlock_bh(rt_hash_lock_addr(i)); | |
905 | sum += length; | |
906 | sum2 += length*length; | |
907 | } | |
908 | if (samples) { | |
909 | unsigned long avg = sum / samples; | |
910 | unsigned long sd = int_sqrt(sum2 / samples - avg*avg); | |
911 | rt_chain_length_max = max_t(unsigned long, | |
912 | ip_rt_gc_elasticity, | |
913 | (avg + 4*sd) >> FRACT_BITS); | |
914 | } | |
915 | rover = i; | |
916 | } | |
917 | ||
918 | /* | |
919 | * rt_worker_func() is run in process context. | |
920 | * we call rt_check_expire() to scan part of the hash table | |
921 | */ | |
922 | static void rt_worker_func(struct work_struct *work) | |
923 | { | |
924 | rt_check_expire(); | |
925 | schedule_delayed_work(&expires_work, ip_rt_gc_interval); | |
926 | } | |
927 | ||
29e75252 | 928 | /* |
25985edc | 929 | * Perturbation of rt_genid by a small quantity [1..256] |
29e75252 ED |
930 | * Using 8 bits of shuffling ensure we can call rt_cache_invalidate() |
931 | * many times (2^24) without giving recent rt_genid. | |
932 | * Jenkins hash is strong enough that litle changes of rt_genid are OK. | |
1da177e4 | 933 | */ |
86c657f6 | 934 | static void rt_cache_invalidate(struct net *net) |
1da177e4 | 935 | { |
29e75252 | 936 | unsigned char shuffle; |
1da177e4 | 937 | |
29e75252 | 938 | get_random_bytes(&shuffle, sizeof(shuffle)); |
e84f84f2 | 939 | atomic_add(shuffle + 1U, &net->ipv4.rt_genid); |
5faa5df1 | 940 | inetpeer_invalidate_tree(AF_INET); |
1da177e4 LT |
941 | } |
942 | ||
29e75252 ED |
943 | /* |
944 | * delay < 0 : invalidate cache (fast : entries will be deleted later) | |
945 | * delay >= 0 : invalidate & flush cache (can be long) | |
946 | */ | |
76e6ebfb | 947 | void rt_cache_flush(struct net *net, int delay) |
1da177e4 | 948 | { |
86c657f6 | 949 | rt_cache_invalidate(net); |
29e75252 | 950 | if (delay >= 0) |
6561a3b1 | 951 | rt_do_flush(net, !in_softirq()); |
1da177e4 LT |
952 | } |
953 | ||
a5ee1551 | 954 | /* Flush previous cache invalidated entries from the cache */ |
6561a3b1 | 955 | void rt_cache_flush_batch(struct net *net) |
a5ee1551 | 956 | { |
6561a3b1 | 957 | rt_do_flush(net, !in_softirq()); |
a5ee1551 EB |
958 | } |
959 | ||
1080d709 NH |
960 | static void rt_emergency_hash_rebuild(struct net *net) |
961 | { | |
3ee94372 | 962 | if (net_ratelimit()) |
058bd4d2 | 963 | pr_warn("Route hash chain too long!\n"); |
3ee94372 | 964 | rt_cache_invalidate(net); |
1080d709 NH |
965 | } |
966 | ||
1da177e4 LT |
967 | /* |
968 | Short description of GC goals. | |
969 | ||
970 | We want to build algorithm, which will keep routing cache | |
971 | at some equilibrium point, when number of aged off entries | |
972 | is kept approximately equal to newly generated ones. | |
973 | ||
974 | Current expiration strength is variable "expire". | |
975 | We try to adjust it dynamically, so that if networking | |
976 | is idle expires is large enough to keep enough of warm entries, | |
977 | and when load increases it reduces to limit cache size. | |
978 | */ | |
979 | ||
569d3645 | 980 | static int rt_garbage_collect(struct dst_ops *ops) |
1da177e4 LT |
981 | { |
982 | static unsigned long expire = RT_GC_TIMEOUT; | |
983 | static unsigned long last_gc; | |
984 | static int rover; | |
985 | static int equilibrium; | |
1c31720a ED |
986 | struct rtable *rth; |
987 | struct rtable __rcu **rthp; | |
1da177e4 LT |
988 | unsigned long now = jiffies; |
989 | int goal; | |
fc66f95c | 990 | int entries = dst_entries_get_fast(&ipv4_dst_ops); |
1da177e4 LT |
991 | |
992 | /* | |
993 | * Garbage collection is pretty expensive, | |
994 | * do not make it too frequently. | |
995 | */ | |
996 | ||
997 | RT_CACHE_STAT_INC(gc_total); | |
998 | ||
999 | if (now - last_gc < ip_rt_gc_min_interval && | |
fc66f95c | 1000 | entries < ip_rt_max_size) { |
1da177e4 LT |
1001 | RT_CACHE_STAT_INC(gc_ignored); |
1002 | goto out; | |
1003 | } | |
1004 | ||
fc66f95c | 1005 | entries = dst_entries_get_slow(&ipv4_dst_ops); |
1da177e4 | 1006 | /* Calculate number of entries, which we want to expire now. */ |
fc66f95c | 1007 | goal = entries - (ip_rt_gc_elasticity << rt_hash_log); |
1da177e4 LT |
1008 | if (goal <= 0) { |
1009 | if (equilibrium < ipv4_dst_ops.gc_thresh) | |
1010 | equilibrium = ipv4_dst_ops.gc_thresh; | |
fc66f95c | 1011 | goal = entries - equilibrium; |
1da177e4 | 1012 | if (goal > 0) { |
b790cedd | 1013 | equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 1014 | goal = entries - equilibrium; |
1da177e4 LT |
1015 | } |
1016 | } else { | |
1017 | /* We are in dangerous area. Try to reduce cache really | |
1018 | * aggressively. | |
1019 | */ | |
b790cedd | 1020 | goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 1021 | equilibrium = entries - goal; |
1da177e4 LT |
1022 | } |
1023 | ||
1024 | if (now - last_gc >= ip_rt_gc_min_interval) | |
1025 | last_gc = now; | |
1026 | ||
1027 | if (goal <= 0) { | |
1028 | equilibrium += goal; | |
1029 | goto work_done; | |
1030 | } | |
1031 | ||
1032 | do { | |
1033 | int i, k; | |
1034 | ||
1035 | for (i = rt_hash_mask, k = rover; i >= 0; i--) { | |
1036 | unsigned long tmo = expire; | |
1037 | ||
1038 | k = (k + 1) & rt_hash_mask; | |
1039 | rthp = &rt_hash_table[k].chain; | |
22c047cc | 1040 | spin_lock_bh(rt_hash_lock_addr(k)); |
1c31720a ED |
1041 | while ((rth = rcu_dereference_protected(*rthp, |
1042 | lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) { | |
e84f84f2 | 1043 | if (!rt_is_expired(rth) && |
29e75252 | 1044 | !rt_may_expire(rth, tmo, expire)) { |
1da177e4 | 1045 | tmo >>= 1; |
d8d1f30b | 1046 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1047 | continue; |
1048 | } | |
d8d1f30b | 1049 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1050 | rt_free(rth); |
1051 | goal--; | |
1da177e4 | 1052 | } |
22c047cc | 1053 | spin_unlock_bh(rt_hash_lock_addr(k)); |
1da177e4 LT |
1054 | if (goal <= 0) |
1055 | break; | |
1056 | } | |
1057 | rover = k; | |
1058 | ||
1059 | if (goal <= 0) | |
1060 | goto work_done; | |
1061 | ||
1062 | /* Goal is not achieved. We stop process if: | |
1063 | ||
1064 | - if expire reduced to zero. Otherwise, expire is halfed. | |
1065 | - if table is not full. | |
1066 | - if we are called from interrupt. | |
1067 | - jiffies check is just fallback/debug loop breaker. | |
1068 | We will not spin here for long time in any case. | |
1069 | */ | |
1070 | ||
1071 | RT_CACHE_STAT_INC(gc_goal_miss); | |
1072 | ||
1073 | if (expire == 0) | |
1074 | break; | |
1075 | ||
1076 | expire >>= 1; | |
1da177e4 | 1077 | |
fc66f95c | 1078 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1da177e4 LT |
1079 | goto out; |
1080 | } while (!in_softirq() && time_before_eq(jiffies, now)); | |
1081 | ||
fc66f95c ED |
1082 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1083 | goto out; | |
1084 | if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size) | |
1da177e4 LT |
1085 | goto out; |
1086 | if (net_ratelimit()) | |
058bd4d2 | 1087 | pr_warn("dst cache overflow\n"); |
1da177e4 LT |
1088 | RT_CACHE_STAT_INC(gc_dst_overflow); |
1089 | return 1; | |
1090 | ||
1091 | work_done: | |
1092 | expire += ip_rt_gc_min_interval; | |
1093 | if (expire > ip_rt_gc_timeout || | |
fc66f95c ED |
1094 | dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh || |
1095 | dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh) | |
1da177e4 | 1096 | expire = ip_rt_gc_timeout; |
1da177e4 LT |
1097 | out: return 0; |
1098 | } | |
1099 | ||
98376387 ED |
1100 | /* |
1101 | * Returns number of entries in a hash chain that have different hash_inputs | |
1102 | */ | |
1103 | static int slow_chain_length(const struct rtable *head) | |
1104 | { | |
1105 | int length = 0; | |
1106 | const struct rtable *rth = head; | |
1107 | ||
1108 | while (rth) { | |
1109 | length += has_noalias(head, rth); | |
1c31720a | 1110 | rth = rcu_dereference_protected(rth->dst.rt_next, 1); |
98376387 ED |
1111 | } |
1112 | return length >> FRACT_BITS; | |
1113 | } | |
1114 | ||
d3aaeb38 | 1115 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr) |
3769cffb | 1116 | { |
d3aaeb38 DM |
1117 | static const __be32 inaddr_any = 0; |
1118 | struct net_device *dev = dst->dev; | |
1119 | const __be32 *pkey = daddr; | |
39232973 | 1120 | const struct rtable *rt; |
3769cffb DM |
1121 | struct neighbour *n; |
1122 | ||
39232973 DM |
1123 | rt = (const struct rtable *) dst; |
1124 | ||
3769cffb | 1125 | if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) |
d3aaeb38 | 1126 | pkey = &inaddr_any; |
39232973 DM |
1127 | else if (rt->rt_gateway) |
1128 | pkey = (const __be32 *) &rt->rt_gateway; | |
d3aaeb38 | 1129 | |
80703d26 | 1130 | n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey); |
d3aaeb38 DM |
1131 | if (n) |
1132 | return n; | |
32092ecf | 1133 | return neigh_create(&arp_tbl, pkey, dev); |
d3aaeb38 DM |
1134 | } |
1135 | ||
1136 | static int rt_bind_neighbour(struct rtable *rt) | |
1137 | { | |
1138 | struct neighbour *n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway); | |
3769cffb DM |
1139 | if (IS_ERR(n)) |
1140 | return PTR_ERR(n); | |
69cce1d1 | 1141 | dst_set_neighbour(&rt->dst, n); |
3769cffb DM |
1142 | |
1143 | return 0; | |
1144 | } | |
1145 | ||
95c96174 | 1146 | static struct rtable *rt_intern_hash(unsigned int hash, struct rtable *rt, |
b23dd4fe | 1147 | struct sk_buff *skb, int ifindex) |
1da177e4 | 1148 | { |
1c31720a ED |
1149 | struct rtable *rth, *cand; |
1150 | struct rtable __rcu **rthp, **candp; | |
1da177e4 | 1151 | unsigned long now; |
1da177e4 LT |
1152 | u32 min_score; |
1153 | int chain_length; | |
1154 | int attempts = !in_softirq(); | |
1155 | ||
1156 | restart: | |
1157 | chain_length = 0; | |
1158 | min_score = ~(u32)0; | |
1159 | cand = NULL; | |
1160 | candp = NULL; | |
1161 | now = jiffies; | |
1162 | ||
d8d1f30b | 1163 | if (!rt_caching(dev_net(rt->dst.dev))) { |
73e42897 NH |
1164 | /* |
1165 | * If we're not caching, just tell the caller we | |
1166 | * were successful and don't touch the route. The | |
1167 | * caller hold the sole reference to the cache entry, and | |
1168 | * it will be released when the caller is done with it. | |
1169 | * If we drop it here, the callers have no way to resolve routes | |
1170 | * when we're not caching. Instead, just point *rp at rt, so | |
1171 | * the caller gets a single use out of the route | |
b6280b47 NH |
1172 | * Note that we do rt_free on this new route entry, so that |
1173 | * once its refcount hits zero, we are still able to reap it | |
1174 | * (Thanks Alexey) | |
27b75c95 ED |
1175 | * Note: To avoid expensive rcu stuff for this uncached dst, |
1176 | * we set DST_NOCACHE so that dst_release() can free dst without | |
1177 | * waiting a grace period. | |
73e42897 | 1178 | */ |
b6280b47 | 1179 | |
c7d4426a | 1180 | rt->dst.flags |= DST_NOCACHE; |
c7537967 | 1181 | if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) { |
3769cffb | 1182 | int err = rt_bind_neighbour(rt); |
b6280b47 NH |
1183 | if (err) { |
1184 | if (net_ratelimit()) | |
058bd4d2 | 1185 | pr_warn("Neighbour table failure & not caching routes\n"); |
27b75c95 | 1186 | ip_rt_put(rt); |
b23dd4fe | 1187 | return ERR_PTR(err); |
b6280b47 NH |
1188 | } |
1189 | } | |
1190 | ||
b6280b47 | 1191 | goto skip_hashing; |
1080d709 NH |
1192 | } |
1193 | ||
1da177e4 LT |
1194 | rthp = &rt_hash_table[hash].chain; |
1195 | ||
22c047cc | 1196 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1c31720a ED |
1197 | while ((rth = rcu_dereference_protected(*rthp, |
1198 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1199 | if (rt_is_expired(rth)) { |
d8d1f30b | 1200 | *rthp = rth->dst.rt_next; |
29e75252 ED |
1201 | rt_free(rth); |
1202 | continue; | |
1203 | } | |
5e2b61f7 | 1204 | if (compare_keys(rth, rt) && compare_netns(rth, rt)) { |
1da177e4 | 1205 | /* Put it first */ |
d8d1f30b | 1206 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1207 | /* |
1208 | * Since lookup is lockfree, the deletion | |
1209 | * must be visible to another weakly ordered CPU before | |
1210 | * the insertion at the start of the hash chain. | |
1211 | */ | |
d8d1f30b | 1212 | rcu_assign_pointer(rth->dst.rt_next, |
1da177e4 LT |
1213 | rt_hash_table[hash].chain); |
1214 | /* | |
1215 | * Since lookup is lockfree, the update writes | |
1216 | * must be ordered for consistency on SMP. | |
1217 | */ | |
1218 | rcu_assign_pointer(rt_hash_table[hash].chain, rth); | |
1219 | ||
d8d1f30b | 1220 | dst_use(&rth->dst, now); |
22c047cc | 1221 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1222 | |
1223 | rt_drop(rt); | |
b23dd4fe | 1224 | if (skb) |
d8d1f30b | 1225 | skb_dst_set(skb, &rth->dst); |
b23dd4fe | 1226 | return rth; |
1da177e4 LT |
1227 | } |
1228 | ||
d8d1f30b | 1229 | if (!atomic_read(&rth->dst.__refcnt)) { |
1da177e4 LT |
1230 | u32 score = rt_score(rth); |
1231 | ||
1232 | if (score <= min_score) { | |
1233 | cand = rth; | |
1234 | candp = rthp; | |
1235 | min_score = score; | |
1236 | } | |
1237 | } | |
1238 | ||
1239 | chain_length++; | |
1240 | ||
d8d1f30b | 1241 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1242 | } |
1243 | ||
1244 | if (cand) { | |
1245 | /* ip_rt_gc_elasticity used to be average length of chain | |
1246 | * length, when exceeded gc becomes really aggressive. | |
1247 | * | |
1248 | * The second limit is less certain. At the moment it allows | |
1249 | * only 2 entries per bucket. We will see. | |
1250 | */ | |
1251 | if (chain_length > ip_rt_gc_elasticity) { | |
d8d1f30b | 1252 | *candp = cand->dst.rt_next; |
1da177e4 LT |
1253 | rt_free(cand); |
1254 | } | |
1080d709 | 1255 | } else { |
98376387 ED |
1256 | if (chain_length > rt_chain_length_max && |
1257 | slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) { | |
d8d1f30b | 1258 | struct net *net = dev_net(rt->dst.dev); |
1080d709 | 1259 | int num = ++net->ipv4.current_rt_cache_rebuild_count; |
b35ecb5d | 1260 | if (!rt_caching(net)) { |
058bd4d2 | 1261 | pr_warn("%s: %d rebuilds is over limit, route caching disabled\n", |
d8d1f30b | 1262 | rt->dst.dev->name, num); |
1080d709 | 1263 | } |
b35ecb5d | 1264 | rt_emergency_hash_rebuild(net); |
6a2bad70 PE |
1265 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1266 | ||
5e2b61f7 | 1267 | hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
6a2bad70 PE |
1268 | ifindex, rt_genid(net)); |
1269 | goto restart; | |
1080d709 | 1270 | } |
1da177e4 LT |
1271 | } |
1272 | ||
1273 | /* Try to bind route to arp only if it is output | |
1274 | route or unicast forwarding path. | |
1275 | */ | |
c7537967 | 1276 | if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) { |
3769cffb | 1277 | int err = rt_bind_neighbour(rt); |
1da177e4 | 1278 | if (err) { |
22c047cc | 1279 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1280 | |
1281 | if (err != -ENOBUFS) { | |
1282 | rt_drop(rt); | |
b23dd4fe | 1283 | return ERR_PTR(err); |
1da177e4 LT |
1284 | } |
1285 | ||
1286 | /* Neighbour tables are full and nothing | |
1287 | can be released. Try to shrink route cache, | |
1288 | it is most likely it holds some neighbour records. | |
1289 | */ | |
1290 | if (attempts-- > 0) { | |
1291 | int saved_elasticity = ip_rt_gc_elasticity; | |
1292 | int saved_int = ip_rt_gc_min_interval; | |
1293 | ip_rt_gc_elasticity = 1; | |
1294 | ip_rt_gc_min_interval = 0; | |
569d3645 | 1295 | rt_garbage_collect(&ipv4_dst_ops); |
1da177e4 LT |
1296 | ip_rt_gc_min_interval = saved_int; |
1297 | ip_rt_gc_elasticity = saved_elasticity; | |
1298 | goto restart; | |
1299 | } | |
1300 | ||
1301 | if (net_ratelimit()) | |
afd46503 | 1302 | pr_warn("Neighbour table overflow\n"); |
1da177e4 | 1303 | rt_drop(rt); |
b23dd4fe | 1304 | return ERR_PTR(-ENOBUFS); |
1da177e4 LT |
1305 | } |
1306 | } | |
1307 | ||
d8d1f30b | 1308 | rt->dst.rt_next = rt_hash_table[hash].chain; |
1080d709 | 1309 | |
00269b54 ED |
1310 | /* |
1311 | * Since lookup is lockfree, we must make sure | |
25985edc | 1312 | * previous writes to rt are committed to memory |
00269b54 ED |
1313 | * before making rt visible to other CPUS. |
1314 | */ | |
1ddbcb00 | 1315 | rcu_assign_pointer(rt_hash_table[hash].chain, rt); |
1080d709 | 1316 | |
22c047cc | 1317 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
73e42897 | 1318 | |
b6280b47 | 1319 | skip_hashing: |
b23dd4fe | 1320 | if (skb) |
d8d1f30b | 1321 | skb_dst_set(skb, &rt->dst); |
b23dd4fe | 1322 | return rt; |
1da177e4 LT |
1323 | } |
1324 | ||
6431cbc2 DM |
1325 | static atomic_t __rt_peer_genid = ATOMIC_INIT(0); |
1326 | ||
1327 | static u32 rt_peer_genid(void) | |
1328 | { | |
1329 | return atomic_read(&__rt_peer_genid); | |
1330 | } | |
1331 | ||
a48eff12 | 1332 | void rt_bind_peer(struct rtable *rt, __be32 daddr, int create) |
1da177e4 | 1333 | { |
1da177e4 LT |
1334 | struct inet_peer *peer; |
1335 | ||
a48eff12 | 1336 | peer = inet_getpeer_v4(daddr, create); |
1da177e4 | 1337 | |
49e8ab03 | 1338 | if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL) |
1da177e4 | 1339 | inet_putpeer(peer); |
6431cbc2 DM |
1340 | else |
1341 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 LT |
1342 | } |
1343 | ||
1344 | /* | |
1345 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
1346 | * we still can generate some output. | |
1347 | * Random ID selection looks a bit dangerous because we have no chances to | |
1348 | * select ID being unique in a reasonable period of time. | |
1349 | * But broken packet identifier may be better than no packet at all. | |
1350 | */ | |
1351 | static void ip_select_fb_ident(struct iphdr *iph) | |
1352 | { | |
1353 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
1354 | static u32 ip_fallback_id; | |
1355 | u32 salt; | |
1356 | ||
1357 | spin_lock_bh(&ip_fb_id_lock); | |
e448515c | 1358 | salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr); |
1da177e4 LT |
1359 | iph->id = htons(salt & 0xFFFF); |
1360 | ip_fallback_id = salt; | |
1361 | spin_unlock_bh(&ip_fb_id_lock); | |
1362 | } | |
1363 | ||
1364 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
1365 | { | |
1366 | struct rtable *rt = (struct rtable *) dst; | |
1367 | ||
e688a604 | 1368 | if (rt && !(rt->dst.flags & DST_NOPEER)) { |
1da177e4 | 1369 | if (rt->peer == NULL) |
a48eff12 | 1370 | rt_bind_peer(rt, rt->rt_dst, 1); |
1da177e4 LT |
1371 | |
1372 | /* If peer is attached to destination, it is never detached, | |
1373 | so that we need not to grab a lock to dereference it. | |
1374 | */ | |
1375 | if (rt->peer) { | |
1376 | iph->id = htons(inet_getid(rt->peer, more)); | |
1377 | return; | |
1378 | } | |
e688a604 | 1379 | } else if (!rt) |
e905a9ed | 1380 | printk(KERN_DEBUG "rt_bind_peer(0) @%p\n", |
9c2b3328 | 1381 | __builtin_return_address(0)); |
1da177e4 LT |
1382 | |
1383 | ip_select_fb_ident(iph); | |
1384 | } | |
4bc2f18b | 1385 | EXPORT_SYMBOL(__ip_select_ident); |
1da177e4 | 1386 | |
95c96174 | 1387 | static void rt_del(unsigned int hash, struct rtable *rt) |
1da177e4 | 1388 | { |
1c31720a ED |
1389 | struct rtable __rcu **rthp; |
1390 | struct rtable *aux; | |
1da177e4 | 1391 | |
29e75252 | 1392 | rthp = &rt_hash_table[hash].chain; |
22c047cc | 1393 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1da177e4 | 1394 | ip_rt_put(rt); |
1c31720a ED |
1395 | while ((aux = rcu_dereference_protected(*rthp, |
1396 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1397 | if (aux == rt || rt_is_expired(aux)) { |
d8d1f30b | 1398 | *rthp = aux->dst.rt_next; |
29e75252 ED |
1399 | rt_free(aux); |
1400 | continue; | |
1da177e4 | 1401 | } |
d8d1f30b | 1402 | rthp = &aux->dst.rt_next; |
29e75252 | 1403 | } |
22c047cc | 1404 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1405 | } |
1406 | ||
de398fb8 | 1407 | static void check_peer_redir(struct dst_entry *dst, struct inet_peer *peer) |
9cc20b26 ED |
1408 | { |
1409 | struct rtable *rt = (struct rtable *) dst; | |
1410 | __be32 orig_gw = rt->rt_gateway; | |
1411 | struct neighbour *n, *old_n; | |
1412 | ||
1413 | dst_confirm(&rt->dst); | |
1414 | ||
1415 | rt->rt_gateway = peer->redirect_learned.a4; | |
1416 | ||
1417 | n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway); | |
de398fb8 DM |
1418 | if (IS_ERR(n)) { |
1419 | rt->rt_gateway = orig_gw; | |
1420 | return; | |
1421 | } | |
9cc20b26 ED |
1422 | old_n = xchg(&rt->dst._neighbour, n); |
1423 | if (old_n) | |
1424 | neigh_release(old_n); | |
de398fb8 DM |
1425 | if (!(n->nud_state & NUD_VALID)) { |
1426 | neigh_event_send(n, NULL); | |
9cc20b26 ED |
1427 | } else { |
1428 | rt->rt_flags |= RTCF_REDIRECTED; | |
1429 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); | |
1430 | } | |
9cc20b26 ED |
1431 | } |
1432 | ||
ed7865a4 | 1433 | /* called in rcu_read_lock() section */ |
f7655229 AV |
1434 | void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, |
1435 | __be32 saddr, struct net_device *dev) | |
1da177e4 | 1436 | { |
7cc9150e | 1437 | int s, i; |
ed7865a4 | 1438 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
7cc9150e FL |
1439 | __be32 skeys[2] = { saddr, 0 }; |
1440 | int ikeys[2] = { dev->ifindex, 0 }; | |
f39925db | 1441 | struct inet_peer *peer; |
317805b8 | 1442 | struct net *net; |
1da177e4 | 1443 | |
1da177e4 LT |
1444 | if (!in_dev) |
1445 | return; | |
1446 | ||
c346dca1 | 1447 | net = dev_net(dev); |
9d4fb27d JP |
1448 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || |
1449 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
1450 | ipv4_is_zeronet(new_gw)) | |
1da177e4 LT |
1451 | goto reject_redirect; |
1452 | ||
1453 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
1454 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
1455 | goto reject_redirect; | |
1456 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
1457 | goto reject_redirect; | |
1458 | } else { | |
317805b8 | 1459 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) |
1da177e4 LT |
1460 | goto reject_redirect; |
1461 | } | |
1462 | ||
7cc9150e FL |
1463 | for (s = 0; s < 2; s++) { |
1464 | for (i = 0; i < 2; i++) { | |
9cc20b26 ED |
1465 | unsigned int hash; |
1466 | struct rtable __rcu **rthp; | |
1467 | struct rtable *rt; | |
1468 | ||
1469 | hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net)); | |
1470 | ||
1471 | rthp = &rt_hash_table[hash].chain; | |
1472 | ||
1473 | while ((rt = rcu_dereference(*rthp)) != NULL) { | |
1474 | rthp = &rt->dst.rt_next; | |
1475 | ||
1476 | if (rt->rt_key_dst != daddr || | |
1477 | rt->rt_key_src != skeys[s] || | |
1478 | rt->rt_oif != ikeys[i] || | |
1479 | rt_is_input_route(rt) || | |
1480 | rt_is_expired(rt) || | |
1481 | !net_eq(dev_net(rt->dst.dev), net) || | |
1482 | rt->dst.error || | |
1483 | rt->dst.dev != dev || | |
1484 | rt->rt_gateway != old_gw) | |
1485 | continue; | |
e905a9ed | 1486 | |
9cc20b26 ED |
1487 | if (!rt->peer) |
1488 | rt_bind_peer(rt, rt->rt_dst, 1); | |
1da177e4 | 1489 | |
9cc20b26 ED |
1490 | peer = rt->peer; |
1491 | if (peer) { | |
ac3f48de | 1492 | if (peer->redirect_learned.a4 != new_gw) { |
9cc20b26 ED |
1493 | peer->redirect_learned.a4 = new_gw; |
1494 | atomic_inc(&__rt_peer_genid); | |
1495 | } | |
1496 | check_peer_redir(&rt->dst, peer); | |
1497 | } | |
7cc9150e | 1498 | } |
7cc9150e | 1499 | } |
1da177e4 | 1500 | } |
1da177e4 LT |
1501 | return; |
1502 | ||
1503 | reject_redirect: | |
1504 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1505 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
058bd4d2 | 1506 | pr_info("Redirect from %pI4 on %s about %pI4 ignored\n" |
673d57e7 | 1507 | " Advised path = %pI4 -> %pI4\n", |
058bd4d2 JP |
1508 | &old_gw, dev->name, &new_gw, |
1509 | &saddr, &daddr); | |
1da177e4 | 1510 | #endif |
ed7865a4 | 1511 | ; |
1da177e4 LT |
1512 | } |
1513 | ||
fe6fe792 ED |
1514 | static bool peer_pmtu_expired(struct inet_peer *peer) |
1515 | { | |
1516 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1517 | ||
1518 | return orig && | |
1519 | time_after_eq(jiffies, orig) && | |
1520 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1521 | } | |
1522 | ||
1523 | static bool peer_pmtu_cleaned(struct inet_peer *peer) | |
1524 | { | |
1525 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1526 | ||
1527 | return orig && | |
1528 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1529 | } | |
1530 | ||
1da177e4 LT |
1531 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) |
1532 | { | |
ee6b9673 | 1533 | struct rtable *rt = (struct rtable *)dst; |
1da177e4 LT |
1534 | struct dst_entry *ret = dst; |
1535 | ||
1536 | if (rt) { | |
d11a4dc1 | 1537 | if (dst->obsolete > 0) { |
1da177e4 LT |
1538 | ip_rt_put(rt); |
1539 | ret = NULL; | |
2c8cec5c | 1540 | } else if (rt->rt_flags & RTCF_REDIRECTED) { |
95c96174 | 1541 | unsigned int hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
5e2b61f7 | 1542 | rt->rt_oif, |
e84f84f2 | 1543 | rt_genid(dev_net(dst->dev))); |
1da177e4 LT |
1544 | rt_del(hash, rt); |
1545 | ret = NULL; | |
fe6fe792 ED |
1546 | } else if (rt->peer && peer_pmtu_expired(rt->peer)) { |
1547 | dst_metric_set(dst, RTAX_MTU, rt->peer->pmtu_orig); | |
1da177e4 LT |
1548 | } |
1549 | } | |
1550 | return ret; | |
1551 | } | |
1552 | ||
1553 | /* | |
1554 | * Algorithm: | |
1555 | * 1. The first ip_rt_redirect_number redirects are sent | |
1556 | * with exponential backoff, then we stop sending them at all, | |
1557 | * assuming that the host ignores our redirects. | |
1558 | * 2. If we did not see packets requiring redirects | |
1559 | * during ip_rt_redirect_silence, we assume that the host | |
1560 | * forgot redirected route and start to send redirects again. | |
1561 | * | |
1562 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
1563 | * in icmp.c. | |
1564 | * | |
1565 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
1566 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
1567 | */ | |
1568 | ||
1569 | void ip_rt_send_redirect(struct sk_buff *skb) | |
1570 | { | |
511c3f92 | 1571 | struct rtable *rt = skb_rtable(skb); |
30038fc6 | 1572 | struct in_device *in_dev; |
92d86829 | 1573 | struct inet_peer *peer; |
30038fc6 | 1574 | int log_martians; |
1da177e4 | 1575 | |
30038fc6 | 1576 | rcu_read_lock(); |
d8d1f30b | 1577 | in_dev = __in_dev_get_rcu(rt->dst.dev); |
30038fc6 ED |
1578 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { |
1579 | rcu_read_unlock(); | |
1da177e4 | 1580 | return; |
30038fc6 ED |
1581 | } |
1582 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
1583 | rcu_read_unlock(); | |
1da177e4 | 1584 | |
92d86829 | 1585 | if (!rt->peer) |
a48eff12 | 1586 | rt_bind_peer(rt, rt->rt_dst, 1); |
92d86829 DM |
1587 | peer = rt->peer; |
1588 | if (!peer) { | |
1589 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
1590 | return; | |
1591 | } | |
1592 | ||
1da177e4 LT |
1593 | /* No redirected packets during ip_rt_redirect_silence; |
1594 | * reset the algorithm. | |
1595 | */ | |
92d86829 DM |
1596 | if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) |
1597 | peer->rate_tokens = 0; | |
1da177e4 LT |
1598 | |
1599 | /* Too many ignored redirects; do not send anything | |
d8d1f30b | 1600 | * set dst.rate_last to the last seen redirected packet. |
1da177e4 | 1601 | */ |
92d86829 DM |
1602 | if (peer->rate_tokens >= ip_rt_redirect_number) { |
1603 | peer->rate_last = jiffies; | |
30038fc6 | 1604 | return; |
1da177e4 LT |
1605 | } |
1606 | ||
1607 | /* Check for load limit; set rate_last to the latest sent | |
1608 | * redirect. | |
1609 | */ | |
92d86829 | 1610 | if (peer->rate_tokens == 0 || |
14fb8a76 | 1611 | time_after(jiffies, |
92d86829 DM |
1612 | (peer->rate_last + |
1613 | (ip_rt_redirect_load << peer->rate_tokens)))) { | |
1da177e4 | 1614 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); |
92d86829 DM |
1615 | peer->rate_last = jiffies; |
1616 | ++peer->rate_tokens; | |
1da177e4 | 1617 | #ifdef CONFIG_IP_ROUTE_VERBOSE |
30038fc6 | 1618 | if (log_martians && |
92d86829 | 1619 | peer->rate_tokens == ip_rt_redirect_number && |
1da177e4 | 1620 | net_ratelimit()) |
058bd4d2 JP |
1621 | pr_warn("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", |
1622 | &ip_hdr(skb)->saddr, rt->rt_iif, | |
673d57e7 | 1623 | &rt->rt_dst, &rt->rt_gateway); |
1da177e4 LT |
1624 | #endif |
1625 | } | |
1da177e4 LT |
1626 | } |
1627 | ||
1628 | static int ip_error(struct sk_buff *skb) | |
1629 | { | |
511c3f92 | 1630 | struct rtable *rt = skb_rtable(skb); |
92d86829 | 1631 | struct inet_peer *peer; |
1da177e4 | 1632 | unsigned long now; |
92d86829 | 1633 | bool send; |
1da177e4 LT |
1634 | int code; |
1635 | ||
d8d1f30b | 1636 | switch (rt->dst.error) { |
4500ebf8 JP |
1637 | case EINVAL: |
1638 | default: | |
1639 | goto out; | |
1640 | case EHOSTUNREACH: | |
1641 | code = ICMP_HOST_UNREACH; | |
1642 | break; | |
1643 | case ENETUNREACH: | |
1644 | code = ICMP_NET_UNREACH; | |
1645 | IP_INC_STATS_BH(dev_net(rt->dst.dev), | |
1646 | IPSTATS_MIB_INNOROUTES); | |
1647 | break; | |
1648 | case EACCES: | |
1649 | code = ICMP_PKT_FILTERED; | |
1650 | break; | |
1da177e4 LT |
1651 | } |
1652 | ||
92d86829 | 1653 | if (!rt->peer) |
a48eff12 | 1654 | rt_bind_peer(rt, rt->rt_dst, 1); |
92d86829 DM |
1655 | peer = rt->peer; |
1656 | ||
1657 | send = true; | |
1658 | if (peer) { | |
1659 | now = jiffies; | |
1660 | peer->rate_tokens += now - peer->rate_last; | |
1661 | if (peer->rate_tokens > ip_rt_error_burst) | |
1662 | peer->rate_tokens = ip_rt_error_burst; | |
1663 | peer->rate_last = now; | |
1664 | if (peer->rate_tokens >= ip_rt_error_cost) | |
1665 | peer->rate_tokens -= ip_rt_error_cost; | |
1666 | else | |
1667 | send = false; | |
1da177e4 | 1668 | } |
92d86829 DM |
1669 | if (send) |
1670 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1da177e4 LT |
1671 | |
1672 | out: kfree_skb(skb); | |
1673 | return 0; | |
e905a9ed | 1674 | } |
1da177e4 LT |
1675 | |
1676 | /* | |
1677 | * The last two values are not from the RFC but | |
1678 | * are needed for AMPRnet AX.25 paths. | |
1679 | */ | |
1680 | ||
9b5b5cff | 1681 | static const unsigned short mtu_plateau[] = |
1da177e4 LT |
1682 | {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 }; |
1683 | ||
5969f71d | 1684 | static inline unsigned short guess_mtu(unsigned short old_mtu) |
1da177e4 LT |
1685 | { |
1686 | int i; | |
e905a9ed | 1687 | |
1da177e4 LT |
1688 | for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++) |
1689 | if (old_mtu > mtu_plateau[i]) | |
1690 | return mtu_plateau[i]; | |
1691 | return 68; | |
1692 | } | |
1693 | ||
b71d1d42 | 1694 | unsigned short ip_rt_frag_needed(struct net *net, const struct iphdr *iph, |
0010e465 TT |
1695 | unsigned short new_mtu, |
1696 | struct net_device *dev) | |
1da177e4 | 1697 | { |
1da177e4 | 1698 | unsigned short old_mtu = ntohs(iph->tot_len); |
1da177e4 | 1699 | unsigned short est_mtu = 0; |
2c8cec5c | 1700 | struct inet_peer *peer; |
1da177e4 | 1701 | |
2c8cec5c DM |
1702 | peer = inet_getpeer_v4(iph->daddr, 1); |
1703 | if (peer) { | |
1704 | unsigned short mtu = new_mtu; | |
1da177e4 | 1705 | |
2c8cec5c DM |
1706 | if (new_mtu < 68 || new_mtu >= old_mtu) { |
1707 | /* BSD 4.2 derived systems incorrectly adjust | |
1708 | * tot_len by the IP header length, and report | |
1709 | * a zero MTU in the ICMP message. | |
1710 | */ | |
1711 | if (mtu == 0 && | |
1712 | old_mtu >= 68 + (iph->ihl << 2)) | |
1713 | old_mtu -= iph->ihl << 2; | |
1714 | mtu = guess_mtu(old_mtu); | |
1715 | } | |
0010e465 | 1716 | |
2c8cec5c DM |
1717 | if (mtu < ip_rt_min_pmtu) |
1718 | mtu = ip_rt_min_pmtu; | |
1719 | if (!peer->pmtu_expires || mtu < peer->pmtu_learned) { | |
46af3180 HS |
1720 | unsigned long pmtu_expires; |
1721 | ||
1722 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1723 | if (!pmtu_expires) | |
1724 | pmtu_expires = 1UL; | |
1725 | ||
2c8cec5c DM |
1726 | est_mtu = mtu; |
1727 | peer->pmtu_learned = mtu; | |
46af3180 | 1728 | peer->pmtu_expires = pmtu_expires; |
59445b6b | 1729 | atomic_inc(&__rt_peer_genid); |
2c8cec5c | 1730 | } |
1da177e4 | 1731 | |
2c8cec5c | 1732 | inet_putpeer(peer); |
1da177e4 LT |
1733 | } |
1734 | return est_mtu ? : new_mtu; | |
1735 | } | |
1736 | ||
2c8cec5c DM |
1737 | static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer) |
1738 | { | |
fe6fe792 | 1739 | unsigned long expires = ACCESS_ONCE(peer->pmtu_expires); |
2c8cec5c | 1740 | |
fe6fe792 ED |
1741 | if (!expires) |
1742 | return; | |
46af3180 | 1743 | if (time_before(jiffies, expires)) { |
2c8cec5c DM |
1744 | u32 orig_dst_mtu = dst_mtu(dst); |
1745 | if (peer->pmtu_learned < orig_dst_mtu) { | |
1746 | if (!peer->pmtu_orig) | |
1747 | peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU); | |
1748 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned); | |
1749 | } | |
1750 | } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires) | |
1751 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); | |
1752 | } | |
1753 | ||
1da177e4 LT |
1754 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) |
1755 | { | |
2c8cec5c DM |
1756 | struct rtable *rt = (struct rtable *) dst; |
1757 | struct inet_peer *peer; | |
1758 | ||
1759 | dst_confirm(dst); | |
1760 | ||
1761 | if (!rt->peer) | |
a48eff12 | 1762 | rt_bind_peer(rt, rt->rt_dst, 1); |
2c8cec5c DM |
1763 | peer = rt->peer; |
1764 | if (peer) { | |
fe6fe792 ED |
1765 | unsigned long pmtu_expires = ACCESS_ONCE(peer->pmtu_expires); |
1766 | ||
2c8cec5c | 1767 | if (mtu < ip_rt_min_pmtu) |
1da177e4 | 1768 | mtu = ip_rt_min_pmtu; |
fe6fe792 | 1769 | if (!pmtu_expires || mtu < peer->pmtu_learned) { |
46af3180 HS |
1770 | |
1771 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1772 | if (!pmtu_expires) | |
1773 | pmtu_expires = 1UL; | |
1774 | ||
2c8cec5c | 1775 | peer->pmtu_learned = mtu; |
46af3180 | 1776 | peer->pmtu_expires = pmtu_expires; |
2c8cec5c DM |
1777 | |
1778 | atomic_inc(&__rt_peer_genid); | |
1779 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 | 1780 | } |
46af3180 | 1781 | check_peer_pmtu(dst, peer); |
1da177e4 LT |
1782 | } |
1783 | } | |
1784 | ||
f39925db | 1785 | |
de398fb8 | 1786 | static void ipv4_validate_peer(struct rtable *rt) |
1da177e4 | 1787 | { |
6431cbc2 | 1788 | if (rt->rt_peer_genid != rt_peer_genid()) { |
2c8cec5c DM |
1789 | struct inet_peer *peer; |
1790 | ||
6431cbc2 | 1791 | if (!rt->peer) |
a48eff12 | 1792 | rt_bind_peer(rt, rt->rt_dst, 0); |
6431cbc2 | 1793 | |
2c8cec5c | 1794 | peer = rt->peer; |
fe6fe792 | 1795 | if (peer) { |
efbc368d | 1796 | check_peer_pmtu(&rt->dst, peer); |
2c8cec5c | 1797 | |
fe6fe792 | 1798 | if (peer->redirect_learned.a4 && |
de398fb8 DM |
1799 | peer->redirect_learned.a4 != rt->rt_gateway) |
1800 | check_peer_redir(&rt->dst, peer); | |
f39925db DM |
1801 | } |
1802 | ||
6431cbc2 DM |
1803 | rt->rt_peer_genid = rt_peer_genid(); |
1804 | } | |
efbc368d DM |
1805 | } |
1806 | ||
1807 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) | |
1808 | { | |
1809 | struct rtable *rt = (struct rtable *) dst; | |
1810 | ||
1811 | if (rt_is_expired(rt)) | |
1812 | return NULL; | |
de398fb8 | 1813 | ipv4_validate_peer(rt); |
d11a4dc1 | 1814 | return dst; |
1da177e4 LT |
1815 | } |
1816 | ||
1817 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1818 | { | |
1819 | struct rtable *rt = (struct rtable *) dst; | |
1820 | struct inet_peer *peer = rt->peer; | |
1da177e4 | 1821 | |
62fa8a84 DM |
1822 | if (rt->fi) { |
1823 | fib_info_put(rt->fi); | |
1824 | rt->fi = NULL; | |
1825 | } | |
1da177e4 LT |
1826 | if (peer) { |
1827 | rt->peer = NULL; | |
1828 | inet_putpeer(peer); | |
1829 | } | |
1da177e4 LT |
1830 | } |
1831 | ||
1da177e4 LT |
1832 | |
1833 | static void ipv4_link_failure(struct sk_buff *skb) | |
1834 | { | |
1835 | struct rtable *rt; | |
1836 | ||
1837 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1838 | ||
511c3f92 | 1839 | rt = skb_rtable(skb); |
fe6fe792 ED |
1840 | if (rt && rt->peer && peer_pmtu_cleaned(rt->peer)) |
1841 | dst_metric_set(&rt->dst, RTAX_MTU, rt->peer->pmtu_orig); | |
1da177e4 LT |
1842 | } |
1843 | ||
1844 | static int ip_rt_bug(struct sk_buff *skb) | |
1845 | { | |
673d57e7 HH |
1846 | printk(KERN_DEBUG "ip_rt_bug: %pI4 -> %pI4, %s\n", |
1847 | &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1da177e4 LT |
1848 | skb->dev ? skb->dev->name : "?"); |
1849 | kfree_skb(skb); | |
c378a9c0 | 1850 | WARN_ON(1); |
1da177e4 LT |
1851 | return 0; |
1852 | } | |
1853 | ||
1854 | /* | |
1855 | We do not cache source address of outgoing interface, | |
1856 | because it is used only by IP RR, TS and SRR options, | |
1857 | so that it out of fast path. | |
1858 | ||
1859 | BTW remember: "addr" is allowed to be not aligned | |
1860 | in IP options! | |
1861 | */ | |
1862 | ||
8e36360a | 1863 | void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) |
1da177e4 | 1864 | { |
a61ced5d | 1865 | __be32 src; |
1da177e4 | 1866 | |
c7537967 | 1867 | if (rt_is_output_route(rt)) |
c5be24ff | 1868 | src = ip_hdr(skb)->saddr; |
ebc0ffae | 1869 | else { |
8e36360a DM |
1870 | struct fib_result res; |
1871 | struct flowi4 fl4; | |
1872 | struct iphdr *iph; | |
1873 | ||
1874 | iph = ip_hdr(skb); | |
1875 | ||
1876 | memset(&fl4, 0, sizeof(fl4)); | |
1877 | fl4.daddr = iph->daddr; | |
1878 | fl4.saddr = iph->saddr; | |
b0fe4a31 | 1879 | fl4.flowi4_tos = RT_TOS(iph->tos); |
8e36360a DM |
1880 | fl4.flowi4_oif = rt->dst.dev->ifindex; |
1881 | fl4.flowi4_iif = skb->dev->ifindex; | |
1882 | fl4.flowi4_mark = skb->mark; | |
5e2b61f7 | 1883 | |
ebc0ffae | 1884 | rcu_read_lock(); |
68a5e3dd | 1885 | if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0) |
436c3b66 | 1886 | src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); |
ebc0ffae ED |
1887 | else |
1888 | src = inet_select_addr(rt->dst.dev, rt->rt_gateway, | |
1da177e4 | 1889 | RT_SCOPE_UNIVERSE); |
ebc0ffae ED |
1890 | rcu_read_unlock(); |
1891 | } | |
1da177e4 LT |
1892 | memcpy(addr, &src, 4); |
1893 | } | |
1894 | ||
c7066f70 | 1895 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1896 | static void set_class_tag(struct rtable *rt, u32 tag) |
1897 | { | |
d8d1f30b CG |
1898 | if (!(rt->dst.tclassid & 0xFFFF)) |
1899 | rt->dst.tclassid |= tag & 0xFFFF; | |
1900 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1901 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1da177e4 LT |
1902 | } |
1903 | #endif | |
1904 | ||
0dbaee3b DM |
1905 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst) |
1906 | { | |
1907 | unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS); | |
1908 | ||
1909 | if (advmss == 0) { | |
1910 | advmss = max_t(unsigned int, dst->dev->mtu - 40, | |
1911 | ip_rt_min_advmss); | |
1912 | if (advmss > 65535 - 40) | |
1913 | advmss = 65535 - 40; | |
1914 | } | |
1915 | return advmss; | |
1916 | } | |
1917 | ||
ebb762f2 | 1918 | static unsigned int ipv4_mtu(const struct dst_entry *dst) |
d33e4553 | 1919 | { |
261663b0 | 1920 | const struct rtable *rt = (const struct rtable *) dst; |
618f9bc7 SK |
1921 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
1922 | ||
261663b0 | 1923 | if (mtu && rt_is_output_route(rt)) |
618f9bc7 SK |
1924 | return mtu; |
1925 | ||
1926 | mtu = dst->dev->mtu; | |
d33e4553 DM |
1927 | |
1928 | if (unlikely(dst_metric_locked(dst, RTAX_MTU))) { | |
d33e4553 DM |
1929 | |
1930 | if (rt->rt_gateway != rt->rt_dst && mtu > 576) | |
1931 | mtu = 576; | |
1932 | } | |
1933 | ||
1934 | if (mtu > IP_MAX_MTU) | |
1935 | mtu = IP_MAX_MTU; | |
1936 | ||
1937 | return mtu; | |
1938 | } | |
1939 | ||
813b3b5d | 1940 | static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1941 | struct fib_info *fi) |
a4daad6b | 1942 | { |
0131ba45 DM |
1943 | struct inet_peer *peer; |
1944 | int create = 0; | |
a4daad6b | 1945 | |
0131ba45 DM |
1946 | /* If a peer entry exists for this destination, we must hook |
1947 | * it up in order to get at cached metrics. | |
1948 | */ | |
813b3b5d | 1949 | if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS)) |
0131ba45 DM |
1950 | create = 1; |
1951 | ||
3c0afdca | 1952 | rt->peer = peer = inet_getpeer_v4(rt->rt_dst, create); |
0131ba45 | 1953 | if (peer) { |
3c0afdca | 1954 | rt->rt_peer_genid = rt_peer_genid(); |
a4daad6b DM |
1955 | if (inet_metrics_new(peer)) |
1956 | memcpy(peer->metrics, fi->fib_metrics, | |
1957 | sizeof(u32) * RTAX_MAX); | |
1958 | dst_init_metrics(&rt->dst, peer->metrics, false); | |
2c8cec5c | 1959 | |
fe6fe792 | 1960 | check_peer_pmtu(&rt->dst, peer); |
ac3f48de | 1961 | |
f39925db DM |
1962 | if (peer->redirect_learned.a4 && |
1963 | peer->redirect_learned.a4 != rt->rt_gateway) { | |
1964 | rt->rt_gateway = peer->redirect_learned.a4; | |
1965 | rt->rt_flags |= RTCF_REDIRECTED; | |
1966 | } | |
0131ba45 DM |
1967 | } else { |
1968 | if (fi->fib_metrics != (u32 *) dst_default_metrics) { | |
1969 | rt->fi = fi; | |
1970 | atomic_inc(&fi->fib_clntref); | |
1971 | } | |
1972 | dst_init_metrics(&rt->dst, fi->fib_metrics, true); | |
a4daad6b DM |
1973 | } |
1974 | } | |
1975 | ||
813b3b5d | 1976 | static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1977 | const struct fib_result *res, |
982721f3 | 1978 | struct fib_info *fi, u16 type, u32 itag) |
1da177e4 | 1979 | { |
defb3519 | 1980 | struct dst_entry *dst = &rt->dst; |
1da177e4 LT |
1981 | |
1982 | if (fi) { | |
1983 | if (FIB_RES_GW(*res) && | |
1984 | FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
1985 | rt->rt_gateway = FIB_RES_GW(*res); | |
813b3b5d | 1986 | rt_init_metrics(rt, fl4, fi); |
c7066f70 | 1987 | #ifdef CONFIG_IP_ROUTE_CLASSID |
defb3519 | 1988 | dst->tclassid = FIB_RES_NH(*res).nh_tclassid; |
1da177e4 | 1989 | #endif |
d33e4553 | 1990 | } |
defb3519 | 1991 | |
defb3519 DM |
1992 | if (dst_mtu(dst) > IP_MAX_MTU) |
1993 | dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU); | |
0dbaee3b | 1994 | if (dst_metric_raw(dst, RTAX_ADVMSS) > 65535 - 40) |
defb3519 | 1995 | dst_metric_set(dst, RTAX_ADVMSS, 65535 - 40); |
1da177e4 | 1996 | |
c7066f70 | 1997 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1998 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
1999 | set_class_tag(rt, fib_rules_tclass(res)); | |
2000 | #endif | |
2001 | set_class_tag(rt, itag); | |
2002 | #endif | |
1da177e4 LT |
2003 | } |
2004 | ||
5c1e6aa3 DM |
2005 | static struct rtable *rt_dst_alloc(struct net_device *dev, |
2006 | bool nopolicy, bool noxfrm) | |
0c4dcd58 | 2007 | { |
5c1e6aa3 DM |
2008 | return dst_alloc(&ipv4_dst_ops, dev, 1, -1, |
2009 | DST_HOST | | |
2010 | (nopolicy ? DST_NOPOLICY : 0) | | |
2011 | (noxfrm ? DST_NOXFRM : 0)); | |
0c4dcd58 DM |
2012 | } |
2013 | ||
96d36220 | 2014 | /* called in rcu_read_lock() section */ |
9e12bb22 | 2015 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
2016 | u8 tos, struct net_device *dev, int our) |
2017 | { | |
96d36220 | 2018 | unsigned int hash; |
1da177e4 | 2019 | struct rtable *rth; |
a61ced5d | 2020 | __be32 spec_dst; |
96d36220 | 2021 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2022 | u32 itag = 0; |
b5f7e755 | 2023 | int err; |
1da177e4 LT |
2024 | |
2025 | /* Primary sanity checks. */ | |
2026 | ||
2027 | if (in_dev == NULL) | |
2028 | return -EINVAL; | |
2029 | ||
1e637c74 | 2030 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
f97c1e0c | 2031 | ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP)) |
1da177e4 LT |
2032 | goto e_inval; |
2033 | ||
f97c1e0c JP |
2034 | if (ipv4_is_zeronet(saddr)) { |
2035 | if (!ipv4_is_local_multicast(daddr)) | |
1da177e4 LT |
2036 | goto e_inval; |
2037 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
b5f7e755 | 2038 | } else { |
5c04c819 MS |
2039 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, &spec_dst, |
2040 | &itag); | |
b5f7e755 ED |
2041 | if (err < 0) |
2042 | goto e_err; | |
2043 | } | |
4e7b2f14 | 2044 | rth = rt_dst_alloc(dev_net(dev)->loopback_dev, |
5c1e6aa3 | 2045 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); |
1da177e4 LT |
2046 | if (!rth) |
2047 | goto e_nobufs; | |
2048 | ||
cf911662 DM |
2049 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2050 | rth->dst.tclassid = itag; | |
2051 | #endif | |
d8d1f30b | 2052 | rth->dst.output = ip_rt_bug; |
1da177e4 | 2053 | |
5e2b61f7 | 2054 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2055 | rth->rt_key_src = saddr; |
cf911662 DM |
2056 | rth->rt_genid = rt_genid(dev_net(dev)); |
2057 | rth->rt_flags = RTCF_MULTICAST; | |
2058 | rth->rt_type = RTN_MULTICAST; | |
475949d8 | 2059 | rth->rt_key_tos = tos; |
cf911662 | 2060 | rth->rt_dst = daddr; |
1da177e4 | 2061 | rth->rt_src = saddr; |
1b86a58f | 2062 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2063 | rth->rt_iif = dev->ifindex; |
5e2b61f7 | 2064 | rth->rt_oif = 0; |
cf911662 | 2065 | rth->rt_mark = skb->mark; |
1da177e4 LT |
2066 | rth->rt_gateway = daddr; |
2067 | rth->rt_spec_dst= spec_dst; | |
cf911662 DM |
2068 | rth->rt_peer_genid = 0; |
2069 | rth->peer = NULL; | |
2070 | rth->fi = NULL; | |
1da177e4 | 2071 | if (our) { |
d8d1f30b | 2072 | rth->dst.input= ip_local_deliver; |
1da177e4 LT |
2073 | rth->rt_flags |= RTCF_LOCAL; |
2074 | } | |
2075 | ||
2076 | #ifdef CONFIG_IP_MROUTE | |
f97c1e0c | 2077 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) |
d8d1f30b | 2078 | rth->dst.input = ip_mr_input; |
1da177e4 LT |
2079 | #endif |
2080 | RT_CACHE_STAT_INC(in_slow_mc); | |
2081 | ||
e84f84f2 | 2082 | hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev))); |
b23dd4fe | 2083 | rth = rt_intern_hash(hash, rth, skb, dev->ifindex); |
9aa3c94c | 2084 | return IS_ERR(rth) ? PTR_ERR(rth) : 0; |
1da177e4 LT |
2085 | |
2086 | e_nobufs: | |
1da177e4 | 2087 | return -ENOBUFS; |
1da177e4 | 2088 | e_inval: |
96d36220 | 2089 | return -EINVAL; |
b5f7e755 | 2090 | e_err: |
b5f7e755 | 2091 | return err; |
1da177e4 LT |
2092 | } |
2093 | ||
2094 | ||
2095 | static void ip_handle_martian_source(struct net_device *dev, | |
2096 | struct in_device *in_dev, | |
2097 | struct sk_buff *skb, | |
9e12bb22 AV |
2098 | __be32 daddr, |
2099 | __be32 saddr) | |
1da177e4 LT |
2100 | { |
2101 | RT_CACHE_STAT_INC(in_martian_src); | |
2102 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2103 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
2104 | /* | |
2105 | * RFC1812 recommendation, if source is martian, | |
2106 | * the only hint is MAC header. | |
2107 | */ | |
058bd4d2 | 2108 | pr_warn("martian source %pI4 from %pI4, on dev %s\n", |
673d57e7 | 2109 | &daddr, &saddr, dev->name); |
98e399f8 | 2110 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { |
058bd4d2 JP |
2111 | print_hex_dump(KERN_WARNING, "ll header: ", |
2112 | DUMP_PREFIX_OFFSET, 16, 1, | |
2113 | skb_mac_header(skb), | |
2114 | dev->hard_header_len, true); | |
1da177e4 LT |
2115 | } |
2116 | } | |
2117 | #endif | |
2118 | } | |
2119 | ||
47360228 | 2120 | /* called in rcu_read_lock() section */ |
5969f71d | 2121 | static int __mkroute_input(struct sk_buff *skb, |
982721f3 | 2122 | const struct fib_result *res, |
5969f71d SH |
2123 | struct in_device *in_dev, |
2124 | __be32 daddr, __be32 saddr, u32 tos, | |
2125 | struct rtable **result) | |
1da177e4 | 2126 | { |
1da177e4 LT |
2127 | struct rtable *rth; |
2128 | int err; | |
2129 | struct in_device *out_dev; | |
47360228 | 2130 | unsigned int flags = 0; |
d9c9df8c AV |
2131 | __be32 spec_dst; |
2132 | u32 itag; | |
1da177e4 LT |
2133 | |
2134 | /* get a working reference to the output device */ | |
47360228 | 2135 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); |
1da177e4 LT |
2136 | if (out_dev == NULL) { |
2137 | if (net_ratelimit()) | |
058bd4d2 | 2138 | pr_crit("Bug in ip_route_input_slow(). Please report.\n"); |
1da177e4 LT |
2139 | return -EINVAL; |
2140 | } | |
2141 | ||
2142 | ||
5c04c819 MS |
2143 | err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), |
2144 | in_dev->dev, &spec_dst, &itag); | |
1da177e4 | 2145 | if (err < 0) { |
e905a9ed | 2146 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, |
1da177e4 | 2147 | saddr); |
e905a9ed | 2148 | |
1da177e4 LT |
2149 | goto cleanup; |
2150 | } | |
2151 | ||
2152 | if (err) | |
2153 | flags |= RTCF_DIRECTSRC; | |
2154 | ||
51b77cae | 2155 | if (out_dev == in_dev && err && |
1da177e4 LT |
2156 | (IN_DEV_SHARED_MEDIA(out_dev) || |
2157 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
2158 | flags |= RTCF_DOREDIRECT; | |
2159 | ||
2160 | if (skb->protocol != htons(ETH_P_IP)) { | |
2161 | /* Not IP (i.e. ARP). Do not create route, if it is | |
2162 | * invalid for proxy arp. DNAT routes are always valid. | |
65324144 JDB |
2163 | * |
2164 | * Proxy arp feature have been extended to allow, ARP | |
2165 | * replies back to the same interface, to support | |
2166 | * Private VLAN switch technologies. See arp.c. | |
1da177e4 | 2167 | */ |
65324144 JDB |
2168 | if (out_dev == in_dev && |
2169 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
1da177e4 LT |
2170 | err = -EINVAL; |
2171 | goto cleanup; | |
2172 | } | |
2173 | } | |
2174 | ||
5c1e6aa3 DM |
2175 | rth = rt_dst_alloc(out_dev->dev, |
2176 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2177 | IN_DEV_CONF_GET(out_dev, NOXFRM)); |
1da177e4 LT |
2178 | if (!rth) { |
2179 | err = -ENOBUFS; | |
2180 | goto cleanup; | |
2181 | } | |
2182 | ||
5e2b61f7 | 2183 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2184 | rth->rt_key_src = saddr; |
cf911662 DM |
2185 | rth->rt_genid = rt_genid(dev_net(rth->dst.dev)); |
2186 | rth->rt_flags = flags; | |
2187 | rth->rt_type = res->type; | |
475949d8 | 2188 | rth->rt_key_tos = tos; |
cf911662 | 2189 | rth->rt_dst = daddr; |
1da177e4 | 2190 | rth->rt_src = saddr; |
1b86a58f | 2191 | rth->rt_route_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2192 | rth->rt_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2193 | rth->rt_oif = 0; |
cf911662 DM |
2194 | rth->rt_mark = skb->mark; |
2195 | rth->rt_gateway = daddr; | |
1da177e4 | 2196 | rth->rt_spec_dst= spec_dst; |
cf911662 DM |
2197 | rth->rt_peer_genid = 0; |
2198 | rth->peer = NULL; | |
2199 | rth->fi = NULL; | |
1da177e4 | 2200 | |
d8d1f30b CG |
2201 | rth->dst.input = ip_forward; |
2202 | rth->dst.output = ip_output; | |
1da177e4 | 2203 | |
5e2b61f7 | 2204 | rt_set_nexthop(rth, NULL, res, res->fi, res->type, itag); |
1da177e4 | 2205 | |
1da177e4 LT |
2206 | *result = rth; |
2207 | err = 0; | |
2208 | cleanup: | |
1da177e4 | 2209 | return err; |
e905a9ed | 2210 | } |
1da177e4 | 2211 | |
5969f71d SH |
2212 | static int ip_mkroute_input(struct sk_buff *skb, |
2213 | struct fib_result *res, | |
68a5e3dd | 2214 | const struct flowi4 *fl4, |
5969f71d SH |
2215 | struct in_device *in_dev, |
2216 | __be32 daddr, __be32 saddr, u32 tos) | |
1da177e4 | 2217 | { |
5e73ea1a | 2218 | struct rtable *rth = NULL; |
1da177e4 | 2219 | int err; |
95c96174 | 2220 | unsigned int hash; |
1da177e4 LT |
2221 | |
2222 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
ff3fccb3 | 2223 | if (res->fi && res->fi->fib_nhs > 1) |
1b7fe593 | 2224 | fib_select_multipath(res); |
1da177e4 LT |
2225 | #endif |
2226 | ||
2227 | /* create a routing cache entry */ | |
2228 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth); | |
2229 | if (err) | |
2230 | return err; | |
1da177e4 LT |
2231 | |
2232 | /* put it into the cache */ | |
68a5e3dd | 2233 | hash = rt_hash(daddr, saddr, fl4->flowi4_iif, |
d8d1f30b | 2234 | rt_genid(dev_net(rth->dst.dev))); |
68a5e3dd | 2235 | rth = rt_intern_hash(hash, rth, skb, fl4->flowi4_iif); |
b23dd4fe DM |
2236 | if (IS_ERR(rth)) |
2237 | return PTR_ERR(rth); | |
2238 | return 0; | |
1da177e4 LT |
2239 | } |
2240 | ||
1da177e4 LT |
2241 | /* |
2242 | * NOTE. We drop all the packets that has local source | |
2243 | * addresses, because every properly looped back packet | |
2244 | * must have correct destination already attached by output routine. | |
2245 | * | |
2246 | * Such approach solves two big problems: | |
2247 | * 1. Not simplex devices are handled properly. | |
2248 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
ebc0ffae | 2249 | * called with rcu_read_lock() |
1da177e4 LT |
2250 | */ |
2251 | ||
9e12bb22 | 2252 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
2253 | u8 tos, struct net_device *dev) |
2254 | { | |
2255 | struct fib_result res; | |
96d36220 | 2256 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
68a5e3dd | 2257 | struct flowi4 fl4; |
95c96174 | 2258 | unsigned int flags = 0; |
1da177e4 | 2259 | u32 itag = 0; |
95c96174 ED |
2260 | struct rtable *rth; |
2261 | unsigned int hash; | |
9e12bb22 | 2262 | __be32 spec_dst; |
1da177e4 | 2263 | int err = -EINVAL; |
5e73ea1a | 2264 | struct net *net = dev_net(dev); |
1da177e4 LT |
2265 | |
2266 | /* IP on this device is disabled. */ | |
2267 | ||
2268 | if (!in_dev) | |
2269 | goto out; | |
2270 | ||
2271 | /* Check for the most weird martians, which can be not detected | |
2272 | by fib_lookup. | |
2273 | */ | |
2274 | ||
1e637c74 | 2275 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
f97c1e0c | 2276 | ipv4_is_loopback(saddr)) |
1da177e4 LT |
2277 | goto martian_source; |
2278 | ||
27a954bd | 2279 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) |
1da177e4 LT |
2280 | goto brd_input; |
2281 | ||
2282 | /* Accept zero addresses only to limited broadcast; | |
2283 | * I even do not know to fix it or not. Waiting for complains :-) | |
2284 | */ | |
f97c1e0c | 2285 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2286 | goto martian_source; |
2287 | ||
27a954bd | 2288 | if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr)) |
1da177e4 LT |
2289 | goto martian_destination; |
2290 | ||
2291 | /* | |
2292 | * Now we are ready to route packet. | |
2293 | */ | |
68a5e3dd DM |
2294 | fl4.flowi4_oif = 0; |
2295 | fl4.flowi4_iif = dev->ifindex; | |
2296 | fl4.flowi4_mark = skb->mark; | |
2297 | fl4.flowi4_tos = tos; | |
2298 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
2299 | fl4.daddr = daddr; | |
2300 | fl4.saddr = saddr; | |
2301 | err = fib_lookup(net, &fl4, &res); | |
ebc0ffae | 2302 | if (err != 0) { |
1da177e4 | 2303 | if (!IN_DEV_FORWARD(in_dev)) |
2c2910a4 | 2304 | goto e_hostunreach; |
1da177e4 LT |
2305 | goto no_route; |
2306 | } | |
1da177e4 LT |
2307 | |
2308 | RT_CACHE_STAT_INC(in_slow_tot); | |
2309 | ||
2310 | if (res.type == RTN_BROADCAST) | |
2311 | goto brd_input; | |
2312 | ||
2313 | if (res.type == RTN_LOCAL) { | |
5c04c819 | 2314 | err = fib_validate_source(skb, saddr, daddr, tos, |
ebc0ffae | 2315 | net->loopback_dev->ifindex, |
5c04c819 | 2316 | dev, &spec_dst, &itag); |
b5f7e755 ED |
2317 | if (err < 0) |
2318 | goto martian_source_keep_err; | |
2319 | if (err) | |
1da177e4 LT |
2320 | flags |= RTCF_DIRECTSRC; |
2321 | spec_dst = daddr; | |
2322 | goto local_input; | |
2323 | } | |
2324 | ||
2325 | if (!IN_DEV_FORWARD(in_dev)) | |
2c2910a4 | 2326 | goto e_hostunreach; |
1da177e4 LT |
2327 | if (res.type != RTN_UNICAST) |
2328 | goto martian_destination; | |
2329 | ||
68a5e3dd | 2330 | err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos); |
1da177e4 LT |
2331 | out: return err; |
2332 | ||
2333 | brd_input: | |
2334 | if (skb->protocol != htons(ETH_P_IP)) | |
2335 | goto e_inval; | |
2336 | ||
f97c1e0c | 2337 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2338 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); |
2339 | else { | |
5c04c819 MS |
2340 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, &spec_dst, |
2341 | &itag); | |
1da177e4 | 2342 | if (err < 0) |
b5f7e755 | 2343 | goto martian_source_keep_err; |
1da177e4 LT |
2344 | if (err) |
2345 | flags |= RTCF_DIRECTSRC; | |
2346 | } | |
2347 | flags |= RTCF_BROADCAST; | |
2348 | res.type = RTN_BROADCAST; | |
2349 | RT_CACHE_STAT_INC(in_brd); | |
2350 | ||
2351 | local_input: | |
5c1e6aa3 DM |
2352 | rth = rt_dst_alloc(net->loopback_dev, |
2353 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); | |
1da177e4 LT |
2354 | if (!rth) |
2355 | goto e_nobufs; | |
2356 | ||
cf911662 | 2357 | rth->dst.input= ip_local_deliver; |
d8d1f30b | 2358 | rth->dst.output= ip_rt_bug; |
cf911662 DM |
2359 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2360 | rth->dst.tclassid = itag; | |
2361 | #endif | |
1da177e4 | 2362 | |
5e2b61f7 | 2363 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2364 | rth->rt_key_src = saddr; |
cf911662 DM |
2365 | rth->rt_genid = rt_genid(net); |
2366 | rth->rt_flags = flags|RTCF_LOCAL; | |
2367 | rth->rt_type = res.type; | |
475949d8 | 2368 | rth->rt_key_tos = tos; |
cf911662 | 2369 | rth->rt_dst = daddr; |
1da177e4 | 2370 | rth->rt_src = saddr; |
c7066f70 | 2371 | #ifdef CONFIG_IP_ROUTE_CLASSID |
d8d1f30b | 2372 | rth->dst.tclassid = itag; |
1da177e4 | 2373 | #endif |
1b86a58f | 2374 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2375 | rth->rt_iif = dev->ifindex; |
cf911662 DM |
2376 | rth->rt_oif = 0; |
2377 | rth->rt_mark = skb->mark; | |
1da177e4 LT |
2378 | rth->rt_gateway = daddr; |
2379 | rth->rt_spec_dst= spec_dst; | |
cf911662 DM |
2380 | rth->rt_peer_genid = 0; |
2381 | rth->peer = NULL; | |
2382 | rth->fi = NULL; | |
1da177e4 | 2383 | if (res.type == RTN_UNREACHABLE) { |
d8d1f30b CG |
2384 | rth->dst.input= ip_error; |
2385 | rth->dst.error= -err; | |
1da177e4 LT |
2386 | rth->rt_flags &= ~RTCF_LOCAL; |
2387 | } | |
68a5e3dd DM |
2388 | hash = rt_hash(daddr, saddr, fl4.flowi4_iif, rt_genid(net)); |
2389 | rth = rt_intern_hash(hash, rth, skb, fl4.flowi4_iif); | |
b23dd4fe DM |
2390 | err = 0; |
2391 | if (IS_ERR(rth)) | |
2392 | err = PTR_ERR(rth); | |
ebc0ffae | 2393 | goto out; |
1da177e4 LT |
2394 | |
2395 | no_route: | |
2396 | RT_CACHE_STAT_INC(in_no_route); | |
2397 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
2398 | res.type = RTN_UNREACHABLE; | |
7f53878d MC |
2399 | if (err == -ESRCH) |
2400 | err = -ENETUNREACH; | |
1da177e4 LT |
2401 | goto local_input; |
2402 | ||
2403 | /* | |
2404 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2405 | */ | |
2406 | martian_destination: | |
2407 | RT_CACHE_STAT_INC(in_martian_dst); | |
2408 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2409 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
058bd4d2 | 2410 | pr_warn("martian destination %pI4 from %pI4, dev %s\n", |
673d57e7 | 2411 | &daddr, &saddr, dev->name); |
1da177e4 | 2412 | #endif |
2c2910a4 DE |
2413 | |
2414 | e_hostunreach: | |
e905a9ed | 2415 | err = -EHOSTUNREACH; |
ebc0ffae | 2416 | goto out; |
2c2910a4 | 2417 | |
1da177e4 LT |
2418 | e_inval: |
2419 | err = -EINVAL; | |
ebc0ffae | 2420 | goto out; |
1da177e4 LT |
2421 | |
2422 | e_nobufs: | |
2423 | err = -ENOBUFS; | |
ebc0ffae | 2424 | goto out; |
1da177e4 LT |
2425 | |
2426 | martian_source: | |
b5f7e755 ED |
2427 | err = -EINVAL; |
2428 | martian_source_keep_err: | |
1da177e4 | 2429 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); |
ebc0ffae | 2430 | goto out; |
1da177e4 LT |
2431 | } |
2432 | ||
407eadd9 ED |
2433 | int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
2434 | u8 tos, struct net_device *dev, bool noref) | |
1da177e4 | 2435 | { |
95c96174 ED |
2436 | struct rtable *rth; |
2437 | unsigned int hash; | |
1da177e4 | 2438 | int iif = dev->ifindex; |
b5921910 | 2439 | struct net *net; |
96d36220 | 2440 | int res; |
1da177e4 | 2441 | |
c346dca1 | 2442 | net = dev_net(dev); |
1080d709 | 2443 | |
96d36220 ED |
2444 | rcu_read_lock(); |
2445 | ||
1080d709 NH |
2446 | if (!rt_caching(net)) |
2447 | goto skip_cache; | |
2448 | ||
1da177e4 | 2449 | tos &= IPTOS_RT_MASK; |
e84f84f2 | 2450 | hash = rt_hash(daddr, saddr, iif, rt_genid(net)); |
1da177e4 | 2451 | |
1da177e4 | 2452 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2453 | rth = rcu_dereference(rth->dst.rt_next)) { |
5e2b61f7 DM |
2454 | if ((((__force u32)rth->rt_key_dst ^ (__force u32)daddr) | |
2455 | ((__force u32)rth->rt_key_src ^ (__force u32)saddr) | | |
97a80410 | 2456 | (rth->rt_route_iif ^ iif) | |
475949d8 | 2457 | (rth->rt_key_tos ^ tos)) == 0 && |
5e2b61f7 | 2458 | rth->rt_mark == skb->mark && |
d8d1f30b | 2459 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2460 | !rt_is_expired(rth)) { |
de398fb8 | 2461 | ipv4_validate_peer(rth); |
407eadd9 | 2462 | if (noref) { |
d8d1f30b CG |
2463 | dst_use_noref(&rth->dst, jiffies); |
2464 | skb_dst_set_noref(skb, &rth->dst); | |
407eadd9 | 2465 | } else { |
d8d1f30b CG |
2466 | dst_use(&rth->dst, jiffies); |
2467 | skb_dst_set(skb, &rth->dst); | |
407eadd9 | 2468 | } |
1da177e4 LT |
2469 | RT_CACHE_STAT_INC(in_hit); |
2470 | rcu_read_unlock(); | |
1da177e4 LT |
2471 | return 0; |
2472 | } | |
2473 | RT_CACHE_STAT_INC(in_hlist_search); | |
2474 | } | |
1da177e4 | 2475 | |
1080d709 | 2476 | skip_cache: |
1da177e4 LT |
2477 | /* Multicast recognition logic is moved from route cache to here. |
2478 | The problem was that too many Ethernet cards have broken/missing | |
2479 | hardware multicast filters :-( As result the host on multicasting | |
2480 | network acquires a lot of useless route cache entries, sort of | |
2481 | SDR messages from all the world. Now we try to get rid of them. | |
2482 | Really, provided software IP multicast filter is organized | |
2483 | reasonably (at least, hashed), it does not result in a slowdown | |
2484 | comparing with route cache reject entries. | |
2485 | Note, that multicast routers are not affected, because | |
2486 | route cache entry is created eventually. | |
2487 | */ | |
f97c1e0c | 2488 | if (ipv4_is_multicast(daddr)) { |
96d36220 | 2489 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2490 | |
96d36220 | 2491 | if (in_dev) { |
dbdd9a52 DM |
2492 | int our = ip_check_mc_rcu(in_dev, daddr, saddr, |
2493 | ip_hdr(skb)->protocol); | |
1da177e4 LT |
2494 | if (our |
2495 | #ifdef CONFIG_IP_MROUTE | |
9d4fb27d JP |
2496 | || |
2497 | (!ipv4_is_local_multicast(daddr) && | |
2498 | IN_DEV_MFORWARD(in_dev)) | |
1da177e4 | 2499 | #endif |
9d4fb27d | 2500 | ) { |
96d36220 ED |
2501 | int res = ip_route_input_mc(skb, daddr, saddr, |
2502 | tos, dev, our); | |
1da177e4 | 2503 | rcu_read_unlock(); |
96d36220 | 2504 | return res; |
1da177e4 LT |
2505 | } |
2506 | } | |
2507 | rcu_read_unlock(); | |
2508 | return -EINVAL; | |
2509 | } | |
96d36220 ED |
2510 | res = ip_route_input_slow(skb, daddr, saddr, tos, dev); |
2511 | rcu_read_unlock(); | |
2512 | return res; | |
1da177e4 | 2513 | } |
407eadd9 | 2514 | EXPORT_SYMBOL(ip_route_input_common); |
1da177e4 | 2515 | |
ebc0ffae | 2516 | /* called with rcu_read_lock() */ |
982721f3 | 2517 | static struct rtable *__mkroute_output(const struct fib_result *res, |
68a5e3dd | 2518 | const struct flowi4 *fl4, |
813b3b5d | 2519 | __be32 orig_daddr, __be32 orig_saddr, |
f61759e6 JA |
2520 | int orig_oif, __u8 orig_rtos, |
2521 | struct net_device *dev_out, | |
5ada5527 | 2522 | unsigned int flags) |
1da177e4 | 2523 | { |
982721f3 | 2524 | struct fib_info *fi = res->fi; |
5ada5527 | 2525 | struct in_device *in_dev; |
982721f3 | 2526 | u16 type = res->type; |
5ada5527 | 2527 | struct rtable *rth; |
1da177e4 | 2528 | |
68a5e3dd | 2529 | if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) |
5ada5527 | 2530 | return ERR_PTR(-EINVAL); |
1da177e4 | 2531 | |
68a5e3dd | 2532 | if (ipv4_is_lbcast(fl4->daddr)) |
982721f3 | 2533 | type = RTN_BROADCAST; |
68a5e3dd | 2534 | else if (ipv4_is_multicast(fl4->daddr)) |
982721f3 | 2535 | type = RTN_MULTICAST; |
68a5e3dd | 2536 | else if (ipv4_is_zeronet(fl4->daddr)) |
5ada5527 | 2537 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
2538 | |
2539 | if (dev_out->flags & IFF_LOOPBACK) | |
2540 | flags |= RTCF_LOCAL; | |
2541 | ||
dd28d1a0 | 2542 | in_dev = __in_dev_get_rcu(dev_out); |
ebc0ffae | 2543 | if (!in_dev) |
5ada5527 | 2544 | return ERR_PTR(-EINVAL); |
ebc0ffae | 2545 | |
982721f3 | 2546 | if (type == RTN_BROADCAST) { |
1da177e4 | 2547 | flags |= RTCF_BROADCAST | RTCF_LOCAL; |
982721f3 DM |
2548 | fi = NULL; |
2549 | } else if (type == RTN_MULTICAST) { | |
dd28d1a0 | 2550 | flags |= RTCF_MULTICAST | RTCF_LOCAL; |
813b3b5d DM |
2551 | if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, |
2552 | fl4->flowi4_proto)) | |
1da177e4 LT |
2553 | flags &= ~RTCF_LOCAL; |
2554 | /* If multicast route do not exist use | |
dd28d1a0 ED |
2555 | * default one, but do not gateway in this case. |
2556 | * Yes, it is hack. | |
1da177e4 | 2557 | */ |
982721f3 DM |
2558 | if (fi && res->prefixlen < 4) |
2559 | fi = NULL; | |
1da177e4 LT |
2560 | } |
2561 | ||
5c1e6aa3 DM |
2562 | rth = rt_dst_alloc(dev_out, |
2563 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2564 | IN_DEV_CONF_GET(in_dev, NOXFRM)); |
8391d07b | 2565 | if (!rth) |
5ada5527 | 2566 | return ERR_PTR(-ENOBUFS); |
8391d07b | 2567 | |
cf911662 DM |
2568 | rth->dst.output = ip_output; |
2569 | ||
813b3b5d DM |
2570 | rth->rt_key_dst = orig_daddr; |
2571 | rth->rt_key_src = orig_saddr; | |
cf911662 DM |
2572 | rth->rt_genid = rt_genid(dev_net(dev_out)); |
2573 | rth->rt_flags = flags; | |
2574 | rth->rt_type = type; | |
f61759e6 | 2575 | rth->rt_key_tos = orig_rtos; |
68a5e3dd DM |
2576 | rth->rt_dst = fl4->daddr; |
2577 | rth->rt_src = fl4->saddr; | |
1b86a58f | 2578 | rth->rt_route_iif = 0; |
813b3b5d DM |
2579 | rth->rt_iif = orig_oif ? : dev_out->ifindex; |
2580 | rth->rt_oif = orig_oif; | |
2581 | rth->rt_mark = fl4->flowi4_mark; | |
68a5e3dd DM |
2582 | rth->rt_gateway = fl4->daddr; |
2583 | rth->rt_spec_dst= fl4->saddr; | |
cf911662 DM |
2584 | rth->rt_peer_genid = 0; |
2585 | rth->peer = NULL; | |
2586 | rth->fi = NULL; | |
1da177e4 LT |
2587 | |
2588 | RT_CACHE_STAT_INC(out_slow_tot); | |
2589 | ||
2590 | if (flags & RTCF_LOCAL) { | |
d8d1f30b | 2591 | rth->dst.input = ip_local_deliver; |
68a5e3dd | 2592 | rth->rt_spec_dst = fl4->daddr; |
1da177e4 LT |
2593 | } |
2594 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { | |
68a5e3dd | 2595 | rth->rt_spec_dst = fl4->saddr; |
e905a9ed | 2596 | if (flags & RTCF_LOCAL && |
1da177e4 | 2597 | !(dev_out->flags & IFF_LOOPBACK)) { |
d8d1f30b | 2598 | rth->dst.output = ip_mc_output; |
1da177e4 LT |
2599 | RT_CACHE_STAT_INC(out_slow_mc); |
2600 | } | |
2601 | #ifdef CONFIG_IP_MROUTE | |
982721f3 | 2602 | if (type == RTN_MULTICAST) { |
1da177e4 | 2603 | if (IN_DEV_MFORWARD(in_dev) && |
813b3b5d | 2604 | !ipv4_is_local_multicast(fl4->daddr)) { |
d8d1f30b CG |
2605 | rth->dst.input = ip_mr_input; |
2606 | rth->dst.output = ip_mc_output; | |
1da177e4 LT |
2607 | } |
2608 | } | |
2609 | #endif | |
2610 | } | |
2611 | ||
813b3b5d | 2612 | rt_set_nexthop(rth, fl4, res, fi, type, 0); |
1da177e4 | 2613 | |
5ada5527 | 2614 | return rth; |
1da177e4 LT |
2615 | } |
2616 | ||
1da177e4 LT |
2617 | /* |
2618 | * Major route resolver routine. | |
0197aa38 | 2619 | * called with rcu_read_lock(); |
1da177e4 LT |
2620 | */ |
2621 | ||
813b3b5d | 2622 | static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4) |
1da177e4 | 2623 | { |
1da177e4 | 2624 | struct net_device *dev_out = NULL; |
f61759e6 | 2625 | __u8 tos = RT_FL_TOS(fl4); |
813b3b5d DM |
2626 | unsigned int flags = 0; |
2627 | struct fib_result res; | |
5ada5527 | 2628 | struct rtable *rth; |
813b3b5d DM |
2629 | __be32 orig_daddr; |
2630 | __be32 orig_saddr; | |
2631 | int orig_oif; | |
1da177e4 LT |
2632 | |
2633 | res.fi = NULL; | |
2634 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
2635 | res.r = NULL; | |
2636 | #endif | |
2637 | ||
813b3b5d DM |
2638 | orig_daddr = fl4->daddr; |
2639 | orig_saddr = fl4->saddr; | |
2640 | orig_oif = fl4->flowi4_oif; | |
2641 | ||
2642 | fl4->flowi4_iif = net->loopback_dev->ifindex; | |
2643 | fl4->flowi4_tos = tos & IPTOS_RT_MASK; | |
2644 | fl4->flowi4_scope = ((tos & RTO_ONLINK) ? | |
2645 | RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); | |
44713b67 | 2646 | |
010c2708 | 2647 | rcu_read_lock(); |
813b3b5d | 2648 | if (fl4->saddr) { |
b23dd4fe | 2649 | rth = ERR_PTR(-EINVAL); |
813b3b5d DM |
2650 | if (ipv4_is_multicast(fl4->saddr) || |
2651 | ipv4_is_lbcast(fl4->saddr) || | |
2652 | ipv4_is_zeronet(fl4->saddr)) | |
1da177e4 LT |
2653 | goto out; |
2654 | ||
1da177e4 LT |
2655 | /* I removed check for oif == dev_out->oif here. |
2656 | It was wrong for two reasons: | |
1ab35276 DL |
2657 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr |
2658 | is assigned to multiple interfaces. | |
1da177e4 LT |
2659 | 2. Moreover, we are allowed to send packets with saddr |
2660 | of another iface. --ANK | |
2661 | */ | |
2662 | ||
813b3b5d DM |
2663 | if (fl4->flowi4_oif == 0 && |
2664 | (ipv4_is_multicast(fl4->daddr) || | |
2665 | ipv4_is_lbcast(fl4->daddr))) { | |
a210d01a | 2666 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2667 | dev_out = __ip_dev_find(net, fl4->saddr, false); |
a210d01a JA |
2668 | if (dev_out == NULL) |
2669 | goto out; | |
2670 | ||
1da177e4 LT |
2671 | /* Special hack: user can direct multicasts |
2672 | and limited broadcast via necessary interface | |
2673 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2674 | This hack is not just for fun, it allows | |
2675 | vic,vat and friends to work. | |
2676 | They bind socket to loopback, set ttl to zero | |
2677 | and expect that it will work. | |
2678 | From the viewpoint of routing cache they are broken, | |
2679 | because we are not allowed to build multicast path | |
2680 | with loopback source addr (look, routing cache | |
2681 | cannot know, that ttl is zero, so that packet | |
2682 | will not leave this host and route is valid). | |
2683 | Luckily, this hack is good workaround. | |
2684 | */ | |
2685 | ||
813b3b5d | 2686 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2687 | goto make_route; |
2688 | } | |
a210d01a | 2689 | |
813b3b5d | 2690 | if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { |
a210d01a | 2691 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2692 | if (!__ip_dev_find(net, fl4->saddr, false)) |
a210d01a | 2693 | goto out; |
a210d01a | 2694 | } |
1da177e4 LT |
2695 | } |
2696 | ||
2697 | ||
813b3b5d DM |
2698 | if (fl4->flowi4_oif) { |
2699 | dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); | |
b23dd4fe | 2700 | rth = ERR_PTR(-ENODEV); |
1da177e4 LT |
2701 | if (dev_out == NULL) |
2702 | goto out; | |
e5ed6399 HX |
2703 | |
2704 | /* RACE: Check return value of inet_select_addr instead. */ | |
fc75fc83 | 2705 | if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { |
b23dd4fe | 2706 | rth = ERR_PTR(-ENETUNREACH); |
fc75fc83 ED |
2707 | goto out; |
2708 | } | |
813b3b5d DM |
2709 | if (ipv4_is_local_multicast(fl4->daddr) || |
2710 | ipv4_is_lbcast(fl4->daddr)) { | |
2711 | if (!fl4->saddr) | |
2712 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2713 | RT_SCOPE_LINK); | |
1da177e4 LT |
2714 | goto make_route; |
2715 | } | |
813b3b5d DM |
2716 | if (fl4->saddr) { |
2717 | if (ipv4_is_multicast(fl4->daddr)) | |
2718 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2719 | fl4->flowi4_scope); | |
2720 | else if (!fl4->daddr) | |
2721 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2722 | RT_SCOPE_HOST); | |
1da177e4 LT |
2723 | } |
2724 | } | |
2725 | ||
813b3b5d DM |
2726 | if (!fl4->daddr) { |
2727 | fl4->daddr = fl4->saddr; | |
2728 | if (!fl4->daddr) | |
2729 | fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); | |
b40afd0e | 2730 | dev_out = net->loopback_dev; |
813b3b5d | 2731 | fl4->flowi4_oif = net->loopback_dev->ifindex; |
1da177e4 LT |
2732 | res.type = RTN_LOCAL; |
2733 | flags |= RTCF_LOCAL; | |
2734 | goto make_route; | |
2735 | } | |
2736 | ||
813b3b5d | 2737 | if (fib_lookup(net, fl4, &res)) { |
1da177e4 | 2738 | res.fi = NULL; |
813b3b5d | 2739 | if (fl4->flowi4_oif) { |
1da177e4 LT |
2740 | /* Apparently, routing tables are wrong. Assume, |
2741 | that the destination is on link. | |
2742 | ||
2743 | WHY? DW. | |
2744 | Because we are allowed to send to iface | |
2745 | even if it has NO routes and NO assigned | |
2746 | addresses. When oif is specified, routing | |
2747 | tables are looked up with only one purpose: | |
2748 | to catch if destination is gatewayed, rather than | |
2749 | direct. Moreover, if MSG_DONTROUTE is set, | |
2750 | we send packet, ignoring both routing tables | |
2751 | and ifaddr state. --ANK | |
2752 | ||
2753 | ||
2754 | We could make it even if oif is unknown, | |
2755 | likely IPv6, but we do not. | |
2756 | */ | |
2757 | ||
813b3b5d DM |
2758 | if (fl4->saddr == 0) |
2759 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2760 | RT_SCOPE_LINK); | |
1da177e4 LT |
2761 | res.type = RTN_UNICAST; |
2762 | goto make_route; | |
2763 | } | |
b23dd4fe | 2764 | rth = ERR_PTR(-ENETUNREACH); |
1da177e4 LT |
2765 | goto out; |
2766 | } | |
1da177e4 LT |
2767 | |
2768 | if (res.type == RTN_LOCAL) { | |
813b3b5d | 2769 | if (!fl4->saddr) { |
9fc3bbb4 | 2770 | if (res.fi->fib_prefsrc) |
813b3b5d | 2771 | fl4->saddr = res.fi->fib_prefsrc; |
9fc3bbb4 | 2772 | else |
813b3b5d | 2773 | fl4->saddr = fl4->daddr; |
9fc3bbb4 | 2774 | } |
b40afd0e | 2775 | dev_out = net->loopback_dev; |
813b3b5d | 2776 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2777 | res.fi = NULL; |
2778 | flags |= RTCF_LOCAL; | |
2779 | goto make_route; | |
2780 | } | |
2781 | ||
2782 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
813b3b5d | 2783 | if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0) |
1b7fe593 | 2784 | fib_select_multipath(&res); |
1da177e4 LT |
2785 | else |
2786 | #endif | |
21d8c49e DM |
2787 | if (!res.prefixlen && |
2788 | res.table->tb_num_default > 1 && | |
813b3b5d | 2789 | res.type == RTN_UNICAST && !fl4->flowi4_oif) |
0c838ff1 | 2790 | fib_select_default(&res); |
1da177e4 | 2791 | |
813b3b5d DM |
2792 | if (!fl4->saddr) |
2793 | fl4->saddr = FIB_RES_PREFSRC(net, res); | |
1da177e4 | 2794 | |
1da177e4 | 2795 | dev_out = FIB_RES_DEV(res); |
813b3b5d | 2796 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2797 | |
2798 | ||
2799 | make_route: | |
813b3b5d | 2800 | rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif, |
f61759e6 | 2801 | tos, dev_out, flags); |
b23dd4fe | 2802 | if (!IS_ERR(rth)) { |
5ada5527 DM |
2803 | unsigned int hash; |
2804 | ||
813b3b5d | 2805 | hash = rt_hash(orig_daddr, orig_saddr, orig_oif, |
5ada5527 | 2806 | rt_genid(dev_net(dev_out))); |
813b3b5d | 2807 | rth = rt_intern_hash(hash, rth, NULL, orig_oif); |
5ada5527 | 2808 | } |
1da177e4 | 2809 | |
010c2708 DM |
2810 | out: |
2811 | rcu_read_unlock(); | |
b23dd4fe | 2812 | return rth; |
1da177e4 LT |
2813 | } |
2814 | ||
813b3b5d | 2815 | struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4) |
1da177e4 | 2816 | { |
1da177e4 | 2817 | struct rtable *rth; |
010c2708 | 2818 | unsigned int hash; |
1da177e4 | 2819 | |
1080d709 NH |
2820 | if (!rt_caching(net)) |
2821 | goto slow_output; | |
2822 | ||
9d6ec938 | 2823 | hash = rt_hash(flp4->daddr, flp4->saddr, flp4->flowi4_oif, rt_genid(net)); |
1da177e4 LT |
2824 | |
2825 | rcu_read_lock_bh(); | |
a898def2 | 2826 | for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2827 | rth = rcu_dereference_bh(rth->dst.rt_next)) { |
9d6ec938 DM |
2828 | if (rth->rt_key_dst == flp4->daddr && |
2829 | rth->rt_key_src == flp4->saddr && | |
c7537967 | 2830 | rt_is_output_route(rth) && |
9d6ec938 DM |
2831 | rth->rt_oif == flp4->flowi4_oif && |
2832 | rth->rt_mark == flp4->flowi4_mark && | |
475949d8 | 2833 | !((rth->rt_key_tos ^ flp4->flowi4_tos) & |
b5921910 | 2834 | (IPTOS_RT_MASK | RTO_ONLINK)) && |
d8d1f30b | 2835 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2836 | !rt_is_expired(rth)) { |
de398fb8 | 2837 | ipv4_validate_peer(rth); |
d8d1f30b | 2838 | dst_use(&rth->dst, jiffies); |
1da177e4 LT |
2839 | RT_CACHE_STAT_INC(out_hit); |
2840 | rcu_read_unlock_bh(); | |
56157872 DM |
2841 | if (!flp4->saddr) |
2842 | flp4->saddr = rth->rt_src; | |
2843 | if (!flp4->daddr) | |
2844 | flp4->daddr = rth->rt_dst; | |
b23dd4fe | 2845 | return rth; |
1da177e4 LT |
2846 | } |
2847 | RT_CACHE_STAT_INC(out_hlist_search); | |
2848 | } | |
2849 | rcu_read_unlock_bh(); | |
2850 | ||
1080d709 | 2851 | slow_output: |
9d6ec938 | 2852 | return ip_route_output_slow(net, flp4); |
1da177e4 | 2853 | } |
d8c97a94 ACM |
2854 | EXPORT_SYMBOL_GPL(__ip_route_output_key); |
2855 | ||
ae2688d5 JW |
2856 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) |
2857 | { | |
2858 | return NULL; | |
2859 | } | |
2860 | ||
ebb762f2 | 2861 | static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst) |
ec831ea7 | 2862 | { |
618f9bc7 SK |
2863 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
2864 | ||
2865 | return mtu ? : dst->dev->mtu; | |
ec831ea7 RD |
2866 | } |
2867 | ||
14e50e57 DM |
2868 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) |
2869 | { | |
2870 | } | |
2871 | ||
0972ddb2 HB |
2872 | static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, |
2873 | unsigned long old) | |
2874 | { | |
2875 | return NULL; | |
2876 | } | |
2877 | ||
14e50e57 DM |
2878 | static struct dst_ops ipv4_dst_blackhole_ops = { |
2879 | .family = AF_INET, | |
09640e63 | 2880 | .protocol = cpu_to_be16(ETH_P_IP), |
14e50e57 | 2881 | .destroy = ipv4_dst_destroy, |
ae2688d5 | 2882 | .check = ipv4_blackhole_dst_check, |
ebb762f2 | 2883 | .mtu = ipv4_blackhole_mtu, |
214f45c9 | 2884 | .default_advmss = ipv4_default_advmss, |
14e50e57 | 2885 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, |
0972ddb2 | 2886 | .cow_metrics = ipv4_rt_blackhole_cow_metrics, |
d3aaeb38 | 2887 | .neigh_lookup = ipv4_neigh_lookup, |
14e50e57 DM |
2888 | }; |
2889 | ||
2774c131 | 2890 | struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) |
14e50e57 | 2891 | { |
5c1e6aa3 | 2892 | struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, 0, 0); |
2774c131 | 2893 | struct rtable *ort = (struct rtable *) dst_orig; |
14e50e57 DM |
2894 | |
2895 | if (rt) { | |
d8d1f30b | 2896 | struct dst_entry *new = &rt->dst; |
14e50e57 | 2897 | |
14e50e57 | 2898 | new->__use = 1; |
352e512c HX |
2899 | new->input = dst_discard; |
2900 | new->output = dst_discard; | |
defb3519 | 2901 | dst_copy_metrics(new, &ort->dst); |
14e50e57 | 2902 | |
d8d1f30b | 2903 | new->dev = ort->dst.dev; |
14e50e57 DM |
2904 | if (new->dev) |
2905 | dev_hold(new->dev); | |
2906 | ||
5e2b61f7 DM |
2907 | rt->rt_key_dst = ort->rt_key_dst; |
2908 | rt->rt_key_src = ort->rt_key_src; | |
475949d8 | 2909 | rt->rt_key_tos = ort->rt_key_tos; |
1b86a58f | 2910 | rt->rt_route_iif = ort->rt_route_iif; |
5e2b61f7 DM |
2911 | rt->rt_iif = ort->rt_iif; |
2912 | rt->rt_oif = ort->rt_oif; | |
2913 | rt->rt_mark = ort->rt_mark; | |
14e50e57 | 2914 | |
e84f84f2 | 2915 | rt->rt_genid = rt_genid(net); |
14e50e57 DM |
2916 | rt->rt_flags = ort->rt_flags; |
2917 | rt->rt_type = ort->rt_type; | |
2918 | rt->rt_dst = ort->rt_dst; | |
2919 | rt->rt_src = ort->rt_src; | |
14e50e57 DM |
2920 | rt->rt_gateway = ort->rt_gateway; |
2921 | rt->rt_spec_dst = ort->rt_spec_dst; | |
2922 | rt->peer = ort->peer; | |
2923 | if (rt->peer) | |
2924 | atomic_inc(&rt->peer->refcnt); | |
62fa8a84 DM |
2925 | rt->fi = ort->fi; |
2926 | if (rt->fi) | |
2927 | atomic_inc(&rt->fi->fib_clntref); | |
14e50e57 DM |
2928 | |
2929 | dst_free(new); | |
2930 | } | |
2931 | ||
2774c131 DM |
2932 | dst_release(dst_orig); |
2933 | ||
2934 | return rt ? &rt->dst : ERR_PTR(-ENOMEM); | |
14e50e57 DM |
2935 | } |
2936 | ||
9d6ec938 | 2937 | struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, |
b23dd4fe | 2938 | struct sock *sk) |
1da177e4 | 2939 | { |
9d6ec938 | 2940 | struct rtable *rt = __ip_route_output_key(net, flp4); |
1da177e4 | 2941 | |
b23dd4fe DM |
2942 | if (IS_ERR(rt)) |
2943 | return rt; | |
1da177e4 | 2944 | |
56157872 | 2945 | if (flp4->flowi4_proto) |
9d6ec938 DM |
2946 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
2947 | flowi4_to_flowi(flp4), | |
2948 | sk, 0); | |
1da177e4 | 2949 | |
b23dd4fe | 2950 | return rt; |
1da177e4 | 2951 | } |
d8c97a94 ACM |
2952 | EXPORT_SYMBOL_GPL(ip_route_output_flow); |
2953 | ||
4feb88e5 BT |
2954 | static int rt_fill_info(struct net *net, |
2955 | struct sk_buff *skb, u32 pid, u32 seq, int event, | |
b6544c0b | 2956 | int nowait, unsigned int flags) |
1da177e4 | 2957 | { |
511c3f92 | 2958 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 2959 | struct rtmsg *r; |
be403ea1 | 2960 | struct nlmsghdr *nlh; |
2bc8ca40 | 2961 | unsigned long expires = 0; |
fe6fe792 | 2962 | const struct inet_peer *peer = rt->peer; |
e3703b3d | 2963 | u32 id = 0, ts = 0, tsage = 0, error; |
be403ea1 TG |
2964 | |
2965 | nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags); | |
2966 | if (nlh == NULL) | |
26932566 | 2967 | return -EMSGSIZE; |
be403ea1 TG |
2968 | |
2969 | r = nlmsg_data(nlh); | |
1da177e4 LT |
2970 | r->rtm_family = AF_INET; |
2971 | r->rtm_dst_len = 32; | |
2972 | r->rtm_src_len = 0; | |
475949d8 | 2973 | r->rtm_tos = rt->rt_key_tos; |
1da177e4 | 2974 | r->rtm_table = RT_TABLE_MAIN; |
f3756b79 DM |
2975 | if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN)) |
2976 | goto nla_put_failure; | |
1da177e4 LT |
2977 | r->rtm_type = rt->rt_type; |
2978 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2979 | r->rtm_protocol = RTPROT_UNSPEC; | |
2980 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2981 | if (rt->rt_flags & RTCF_NOTIFY) | |
2982 | r->rtm_flags |= RTM_F_NOTIFY; | |
be403ea1 | 2983 | |
f3756b79 DM |
2984 | if (nla_put_be32(skb, RTA_DST, rt->rt_dst)) |
2985 | goto nla_put_failure; | |
5e2b61f7 | 2986 | if (rt->rt_key_src) { |
1da177e4 | 2987 | r->rtm_src_len = 32; |
f3756b79 DM |
2988 | if (nla_put_be32(skb, RTA_SRC, rt->rt_key_src)) |
2989 | goto nla_put_failure; | |
1da177e4 | 2990 | } |
f3756b79 DM |
2991 | if (rt->dst.dev && |
2992 | nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) | |
2993 | goto nla_put_failure; | |
c7066f70 | 2994 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
2995 | if (rt->dst.tclassid && |
2996 | nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid)) | |
2997 | goto nla_put_failure; | |
1da177e4 | 2998 | #endif |
f3756b79 DM |
2999 | if (rt_is_input_route(rt)) { |
3000 | if (nla_put_be32(skb, RTA_PREFSRC, rt->rt_spec_dst)) | |
3001 | goto nla_put_failure; | |
3002 | } else if (rt->rt_src != rt->rt_key_src) { | |
3003 | if (nla_put_be32(skb, RTA_PREFSRC, rt->rt_src)) | |
3004 | goto nla_put_failure; | |
3005 | } | |
3006 | if (rt->rt_dst != rt->rt_gateway && | |
3007 | nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway)) | |
3008 | goto nla_put_failure; | |
be403ea1 | 3009 | |
defb3519 | 3010 | if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) |
be403ea1 TG |
3011 | goto nla_put_failure; |
3012 | ||
f3756b79 DM |
3013 | if (rt->rt_mark && |
3014 | nla_put_be32(skb, RTA_MARK, rt->rt_mark)) | |
3015 | goto nla_put_failure; | |
963bfeee | 3016 | |
d8d1f30b | 3017 | error = rt->dst.error; |
fe6fe792 | 3018 | if (peer) { |
317fe0e6 | 3019 | inet_peer_refcheck(rt->peer); |
fe6fe792 ED |
3020 | id = atomic_read(&peer->ip_id_count) & 0xffff; |
3021 | if (peer->tcp_ts_stamp) { | |
3022 | ts = peer->tcp_ts; | |
3023 | tsage = get_seconds() - peer->tcp_ts_stamp; | |
1da177e4 | 3024 | } |
fe6fe792 | 3025 | expires = ACCESS_ONCE(peer->pmtu_expires); |
2bc8ca40 SK |
3026 | if (expires) { |
3027 | if (time_before(jiffies, expires)) | |
3028 | expires -= jiffies; | |
3029 | else | |
3030 | expires = 0; | |
3031 | } | |
1da177e4 | 3032 | } |
be403ea1 | 3033 | |
c7537967 | 3034 | if (rt_is_input_route(rt)) { |
1da177e4 | 3035 | #ifdef CONFIG_IP_MROUTE |
e448515c | 3036 | __be32 dst = rt->rt_dst; |
1da177e4 | 3037 | |
f97c1e0c | 3038 | if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) && |
4feb88e5 | 3039 | IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { |
9a1b9496 DM |
3040 | int err = ipmr_get_route(net, skb, |
3041 | rt->rt_src, rt->rt_dst, | |
3042 | r, nowait); | |
1da177e4 LT |
3043 | if (err <= 0) { |
3044 | if (!nowait) { | |
3045 | if (err == 0) | |
3046 | return 0; | |
be403ea1 | 3047 | goto nla_put_failure; |
1da177e4 LT |
3048 | } else { |
3049 | if (err == -EMSGSIZE) | |
be403ea1 | 3050 | goto nla_put_failure; |
e3703b3d | 3051 | error = err; |
1da177e4 LT |
3052 | } |
3053 | } | |
3054 | } else | |
3055 | #endif | |
f3756b79 DM |
3056 | if (nla_put_u32(skb, RTA_IIF, rt->rt_iif)) |
3057 | goto nla_put_failure; | |
1da177e4 LT |
3058 | } |
3059 | ||
d8d1f30b | 3060 | if (rtnl_put_cacheinfo(skb, &rt->dst, id, ts, tsage, |
e3703b3d TG |
3061 | expires, error) < 0) |
3062 | goto nla_put_failure; | |
be403ea1 TG |
3063 | |
3064 | return nlmsg_end(skb, nlh); | |
1da177e4 | 3065 | |
be403ea1 | 3066 | nla_put_failure: |
26932566 PM |
3067 | nlmsg_cancel(skb, nlh); |
3068 | return -EMSGSIZE; | |
1da177e4 LT |
3069 | } |
3070 | ||
5e73ea1a | 3071 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg) |
1da177e4 | 3072 | { |
3b1e0a65 | 3073 | struct net *net = sock_net(in_skb->sk); |
d889ce3b TG |
3074 | struct rtmsg *rtm; |
3075 | struct nlattr *tb[RTA_MAX+1]; | |
1da177e4 | 3076 | struct rtable *rt = NULL; |
9e12bb22 AV |
3077 | __be32 dst = 0; |
3078 | __be32 src = 0; | |
3079 | u32 iif; | |
d889ce3b | 3080 | int err; |
963bfeee | 3081 | int mark; |
1da177e4 LT |
3082 | struct sk_buff *skb; |
3083 | ||
d889ce3b TG |
3084 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); |
3085 | if (err < 0) | |
3086 | goto errout; | |
3087 | ||
3088 | rtm = nlmsg_data(nlh); | |
3089 | ||
1da177e4 | 3090 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
d889ce3b TG |
3091 | if (skb == NULL) { |
3092 | err = -ENOBUFS; | |
3093 | goto errout; | |
3094 | } | |
1da177e4 LT |
3095 | |
3096 | /* Reserve room for dummy headers, this skb can pass | |
3097 | through good chunk of routing engine. | |
3098 | */ | |
459a98ed | 3099 | skb_reset_mac_header(skb); |
c1d2bbe1 | 3100 | skb_reset_network_header(skb); |
d2c962b8 SH |
3101 | |
3102 | /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ | |
eddc9ec5 | 3103 | ip_hdr(skb)->protocol = IPPROTO_ICMP; |
1da177e4 LT |
3104 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); |
3105 | ||
17fb2c64 AV |
3106 | src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0; |
3107 | dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; | |
d889ce3b | 3108 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; |
963bfeee | 3109 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; |
1da177e4 LT |
3110 | |
3111 | if (iif) { | |
d889ce3b TG |
3112 | struct net_device *dev; |
3113 | ||
1937504d | 3114 | dev = __dev_get_by_index(net, iif); |
d889ce3b TG |
3115 | if (dev == NULL) { |
3116 | err = -ENODEV; | |
3117 | goto errout_free; | |
3118 | } | |
3119 | ||
1da177e4 LT |
3120 | skb->protocol = htons(ETH_P_IP); |
3121 | skb->dev = dev; | |
963bfeee | 3122 | skb->mark = mark; |
1da177e4 LT |
3123 | local_bh_disable(); |
3124 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
3125 | local_bh_enable(); | |
d889ce3b | 3126 | |
511c3f92 | 3127 | rt = skb_rtable(skb); |
d8d1f30b CG |
3128 | if (err == 0 && rt->dst.error) |
3129 | err = -rt->dst.error; | |
1da177e4 | 3130 | } else { |
68a5e3dd DM |
3131 | struct flowi4 fl4 = { |
3132 | .daddr = dst, | |
3133 | .saddr = src, | |
3134 | .flowi4_tos = rtm->rtm_tos, | |
3135 | .flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0, | |
3136 | .flowi4_mark = mark, | |
d889ce3b | 3137 | }; |
9d6ec938 | 3138 | rt = ip_route_output_key(net, &fl4); |
b23dd4fe DM |
3139 | |
3140 | err = 0; | |
3141 | if (IS_ERR(rt)) | |
3142 | err = PTR_ERR(rt); | |
1da177e4 | 3143 | } |
d889ce3b | 3144 | |
1da177e4 | 3145 | if (err) |
d889ce3b | 3146 | goto errout_free; |
1da177e4 | 3147 | |
d8d1f30b | 3148 | skb_dst_set(skb, &rt->dst); |
1da177e4 LT |
3149 | if (rtm->rtm_flags & RTM_F_NOTIFY) |
3150 | rt->rt_flags |= RTCF_NOTIFY; | |
3151 | ||
4feb88e5 | 3152 | err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, |
1937504d | 3153 | RTM_NEWROUTE, 0, 0); |
d889ce3b TG |
3154 | if (err <= 0) |
3155 | goto errout_free; | |
1da177e4 | 3156 | |
1937504d | 3157 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); |
d889ce3b | 3158 | errout: |
2942e900 | 3159 | return err; |
1da177e4 | 3160 | |
d889ce3b | 3161 | errout_free: |
1da177e4 | 3162 | kfree_skb(skb); |
d889ce3b | 3163 | goto errout; |
1da177e4 LT |
3164 | } |
3165 | ||
3166 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
3167 | { | |
3168 | struct rtable *rt; | |
3169 | int h, s_h; | |
3170 | int idx, s_idx; | |
1937504d DL |
3171 | struct net *net; |
3172 | ||
3b1e0a65 | 3173 | net = sock_net(skb->sk); |
1da177e4 LT |
3174 | |
3175 | s_h = cb->args[0]; | |
d8c92830 ED |
3176 | if (s_h < 0) |
3177 | s_h = 0; | |
1da177e4 | 3178 | s_idx = idx = cb->args[1]; |
a6272665 ED |
3179 | for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) { |
3180 | if (!rt_hash_table[h].chain) | |
3181 | continue; | |
1da177e4 | 3182 | rcu_read_lock_bh(); |
a898def2 | 3183 | for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt; |
d8d1f30b CG |
3184 | rt = rcu_dereference_bh(rt->dst.rt_next), idx++) { |
3185 | if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx) | |
1da177e4 | 3186 | continue; |
e84f84f2 | 3187 | if (rt_is_expired(rt)) |
29e75252 | 3188 | continue; |
d8d1f30b | 3189 | skb_dst_set_noref(skb, &rt->dst); |
4feb88e5 | 3190 | if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid, |
e905a9ed | 3191 | cb->nlh->nlmsg_seq, RTM_NEWROUTE, |
b6544c0b | 3192 | 1, NLM_F_MULTI) <= 0) { |
adf30907 | 3193 | skb_dst_drop(skb); |
1da177e4 LT |
3194 | rcu_read_unlock_bh(); |
3195 | goto done; | |
3196 | } | |
adf30907 | 3197 | skb_dst_drop(skb); |
1da177e4 LT |
3198 | } |
3199 | rcu_read_unlock_bh(); | |
3200 | } | |
3201 | ||
3202 | done: | |
3203 | cb->args[0] = h; | |
3204 | cb->args[1] = idx; | |
3205 | return skb->len; | |
3206 | } | |
3207 | ||
3208 | void ip_rt_multicast_event(struct in_device *in_dev) | |
3209 | { | |
76e6ebfb | 3210 | rt_cache_flush(dev_net(in_dev->dev), 0); |
1da177e4 LT |
3211 | } |
3212 | ||
3213 | #ifdef CONFIG_SYSCTL | |
81c684d1 | 3214 | static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, |
8d65af78 | 3215 | void __user *buffer, |
1da177e4 LT |
3216 | size_t *lenp, loff_t *ppos) |
3217 | { | |
3218 | if (write) { | |
639e104f | 3219 | int flush_delay; |
81c684d1 | 3220 | ctl_table ctl; |
39a23e75 | 3221 | struct net *net; |
639e104f | 3222 | |
81c684d1 DL |
3223 | memcpy(&ctl, __ctl, sizeof(ctl)); |
3224 | ctl.data = &flush_delay; | |
8d65af78 | 3225 | proc_dointvec(&ctl, write, buffer, lenp, ppos); |
639e104f | 3226 | |
81c684d1 | 3227 | net = (struct net *)__ctl->extra1; |
39a23e75 | 3228 | rt_cache_flush(net, flush_delay); |
1da177e4 | 3229 | return 0; |
e905a9ed | 3230 | } |
1da177e4 LT |
3231 | |
3232 | return -EINVAL; | |
3233 | } | |
3234 | ||
eeb61f71 | 3235 | static ctl_table ipv4_route_table[] = { |
1da177e4 | 3236 | { |
1da177e4 LT |
3237 | .procname = "gc_thresh", |
3238 | .data = &ipv4_dst_ops.gc_thresh, | |
3239 | .maxlen = sizeof(int), | |
3240 | .mode = 0644, | |
6d9f239a | 3241 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3242 | }, |
3243 | { | |
1da177e4 LT |
3244 | .procname = "max_size", |
3245 | .data = &ip_rt_max_size, | |
3246 | .maxlen = sizeof(int), | |
3247 | .mode = 0644, | |
6d9f239a | 3248 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3249 | }, |
3250 | { | |
3251 | /* Deprecated. Use gc_min_interval_ms */ | |
e905a9ed | 3252 | |
1da177e4 LT |
3253 | .procname = "gc_min_interval", |
3254 | .data = &ip_rt_gc_min_interval, | |
3255 | .maxlen = sizeof(int), | |
3256 | .mode = 0644, | |
6d9f239a | 3257 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3258 | }, |
3259 | { | |
1da177e4 LT |
3260 | .procname = "gc_min_interval_ms", |
3261 | .data = &ip_rt_gc_min_interval, | |
3262 | .maxlen = sizeof(int), | |
3263 | .mode = 0644, | |
6d9f239a | 3264 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 LT |
3265 | }, |
3266 | { | |
1da177e4 LT |
3267 | .procname = "gc_timeout", |
3268 | .data = &ip_rt_gc_timeout, | |
3269 | .maxlen = sizeof(int), | |
3270 | .mode = 0644, | |
6d9f239a | 3271 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 | 3272 | }, |
9f28a2fc ED |
3273 | { |
3274 | .procname = "gc_interval", | |
3275 | .data = &ip_rt_gc_interval, | |
3276 | .maxlen = sizeof(int), | |
3277 | .mode = 0644, | |
3278 | .proc_handler = proc_dointvec_jiffies, | |
3279 | }, | |
1da177e4 | 3280 | { |
1da177e4 LT |
3281 | .procname = "redirect_load", |
3282 | .data = &ip_rt_redirect_load, | |
3283 | .maxlen = sizeof(int), | |
3284 | .mode = 0644, | |
6d9f239a | 3285 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3286 | }, |
3287 | { | |
1da177e4 LT |
3288 | .procname = "redirect_number", |
3289 | .data = &ip_rt_redirect_number, | |
3290 | .maxlen = sizeof(int), | |
3291 | .mode = 0644, | |
6d9f239a | 3292 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3293 | }, |
3294 | { | |
1da177e4 LT |
3295 | .procname = "redirect_silence", |
3296 | .data = &ip_rt_redirect_silence, | |
3297 | .maxlen = sizeof(int), | |
3298 | .mode = 0644, | |
6d9f239a | 3299 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3300 | }, |
3301 | { | |
1da177e4 LT |
3302 | .procname = "error_cost", |
3303 | .data = &ip_rt_error_cost, | |
3304 | .maxlen = sizeof(int), | |
3305 | .mode = 0644, | |
6d9f239a | 3306 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3307 | }, |
3308 | { | |
1da177e4 LT |
3309 | .procname = "error_burst", |
3310 | .data = &ip_rt_error_burst, | |
3311 | .maxlen = sizeof(int), | |
3312 | .mode = 0644, | |
6d9f239a | 3313 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3314 | }, |
3315 | { | |
1da177e4 LT |
3316 | .procname = "gc_elasticity", |
3317 | .data = &ip_rt_gc_elasticity, | |
3318 | .maxlen = sizeof(int), | |
3319 | .mode = 0644, | |
6d9f239a | 3320 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3321 | }, |
3322 | { | |
1da177e4 LT |
3323 | .procname = "mtu_expires", |
3324 | .data = &ip_rt_mtu_expires, | |
3325 | .maxlen = sizeof(int), | |
3326 | .mode = 0644, | |
6d9f239a | 3327 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3328 | }, |
3329 | { | |
1da177e4 LT |
3330 | .procname = "min_pmtu", |
3331 | .data = &ip_rt_min_pmtu, | |
3332 | .maxlen = sizeof(int), | |
3333 | .mode = 0644, | |
6d9f239a | 3334 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3335 | }, |
3336 | { | |
1da177e4 LT |
3337 | .procname = "min_adv_mss", |
3338 | .data = &ip_rt_min_advmss, | |
3339 | .maxlen = sizeof(int), | |
3340 | .mode = 0644, | |
6d9f239a | 3341 | .proc_handler = proc_dointvec, |
1da177e4 | 3342 | }, |
f8572d8f | 3343 | { } |
1da177e4 | 3344 | }; |
39a23e75 | 3345 | |
2f4520d3 AV |
3346 | static struct ctl_table empty[1]; |
3347 | ||
3348 | static struct ctl_table ipv4_skeleton[] = | |
3349 | { | |
f8572d8f | 3350 | { .procname = "route", |
d994af0d | 3351 | .mode = 0555, .child = ipv4_route_table}, |
f8572d8f | 3352 | { .procname = "neigh", |
d994af0d | 3353 | .mode = 0555, .child = empty}, |
2f4520d3 AV |
3354 | { } |
3355 | }; | |
3356 | ||
3357 | static __net_initdata struct ctl_path ipv4_path[] = { | |
f8572d8f EB |
3358 | { .procname = "net", }, |
3359 | { .procname = "ipv4", }, | |
39a23e75 DL |
3360 | { }, |
3361 | }; | |
3362 | ||
39a23e75 DL |
3363 | static struct ctl_table ipv4_route_flush_table[] = { |
3364 | { | |
39a23e75 DL |
3365 | .procname = "flush", |
3366 | .maxlen = sizeof(int), | |
3367 | .mode = 0200, | |
6d9f239a | 3368 | .proc_handler = ipv4_sysctl_rtcache_flush, |
39a23e75 | 3369 | }, |
f8572d8f | 3370 | { }, |
39a23e75 DL |
3371 | }; |
3372 | ||
2f4520d3 | 3373 | static __net_initdata struct ctl_path ipv4_route_path[] = { |
f8572d8f EB |
3374 | { .procname = "net", }, |
3375 | { .procname = "ipv4", }, | |
3376 | { .procname = "route", }, | |
2f4520d3 AV |
3377 | { }, |
3378 | }; | |
3379 | ||
39a23e75 DL |
3380 | static __net_init int sysctl_route_net_init(struct net *net) |
3381 | { | |
3382 | struct ctl_table *tbl; | |
3383 | ||
3384 | tbl = ipv4_route_flush_table; | |
09ad9bc7 | 3385 | if (!net_eq(net, &init_net)) { |
39a23e75 DL |
3386 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); |
3387 | if (tbl == NULL) | |
3388 | goto err_dup; | |
3389 | } | |
3390 | tbl[0].extra1 = net; | |
3391 | ||
3392 | net->ipv4.route_hdr = | |
3393 | register_net_sysctl_table(net, ipv4_route_path, tbl); | |
3394 | if (net->ipv4.route_hdr == NULL) | |
3395 | goto err_reg; | |
3396 | return 0; | |
3397 | ||
3398 | err_reg: | |
3399 | if (tbl != ipv4_route_flush_table) | |
3400 | kfree(tbl); | |
3401 | err_dup: | |
3402 | return -ENOMEM; | |
3403 | } | |
3404 | ||
3405 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
3406 | { | |
3407 | struct ctl_table *tbl; | |
3408 | ||
3409 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
3410 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
3411 | BUG_ON(tbl == ipv4_route_flush_table); | |
3412 | kfree(tbl); | |
3413 | } | |
3414 | ||
3415 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
3416 | .init = sysctl_route_net_init, | |
3417 | .exit = sysctl_route_net_exit, | |
3418 | }; | |
1da177e4 LT |
3419 | #endif |
3420 | ||
3ee94372 | 3421 | static __net_init int rt_genid_init(struct net *net) |
9f5e97e5 | 3422 | { |
3ee94372 NH |
3423 | get_random_bytes(&net->ipv4.rt_genid, |
3424 | sizeof(net->ipv4.rt_genid)); | |
436c3b66 DM |
3425 | get_random_bytes(&net->ipv4.dev_addr_genid, |
3426 | sizeof(net->ipv4.dev_addr_genid)); | |
9f5e97e5 DL |
3427 | return 0; |
3428 | } | |
3429 | ||
3ee94372 NH |
3430 | static __net_initdata struct pernet_operations rt_genid_ops = { |
3431 | .init = rt_genid_init, | |
9f5e97e5 DL |
3432 | }; |
3433 | ||
3434 | ||
c7066f70 | 3435 | #ifdef CONFIG_IP_ROUTE_CLASSID |
7d720c3e | 3436 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; |
c7066f70 | 3437 | #endif /* CONFIG_IP_ROUTE_CLASSID */ |
1da177e4 LT |
3438 | |
3439 | static __initdata unsigned long rhash_entries; | |
3440 | static int __init set_rhash_entries(char *str) | |
3441 | { | |
3442 | if (!str) | |
3443 | return 0; | |
3444 | rhash_entries = simple_strtoul(str, &str, 0); | |
3445 | return 1; | |
3446 | } | |
3447 | __setup("rhash_entries=", set_rhash_entries); | |
3448 | ||
3449 | int __init ip_rt_init(void) | |
3450 | { | |
424c4b70 | 3451 | int rc = 0; |
1da177e4 | 3452 | |
c7066f70 | 3453 | #ifdef CONFIG_IP_ROUTE_CLASSID |
0dcec8c2 | 3454 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); |
1da177e4 LT |
3455 | if (!ip_rt_acct) |
3456 | panic("IP: failed to allocate ip_rt_acct\n"); | |
1da177e4 LT |
3457 | #endif |
3458 | ||
e5d679f3 AD |
3459 | ipv4_dst_ops.kmem_cachep = |
3460 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
20c2df83 | 3461 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 3462 | |
14e50e57 DM |
3463 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; |
3464 | ||
fc66f95c ED |
3465 | if (dst_entries_init(&ipv4_dst_ops) < 0) |
3466 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
3467 | ||
3468 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
3469 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
3470 | ||
424c4b70 ED |
3471 | rt_hash_table = (struct rt_hash_bucket *) |
3472 | alloc_large_system_hash("IP route cache", | |
3473 | sizeof(struct rt_hash_bucket), | |
3474 | rhash_entries, | |
4481374c | 3475 | (totalram_pages >= 128 * 1024) ? |
18955cfc | 3476 | 15 : 17, |
8d1502de | 3477 | 0, |
424c4b70 ED |
3478 | &rt_hash_log, |
3479 | &rt_hash_mask, | |
c9503e0f | 3480 | rhash_entries ? 0 : 512 * 1024); |
22c047cc ED |
3481 | memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket)); |
3482 | rt_hash_lock_init(); | |
1da177e4 LT |
3483 | |
3484 | ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1); | |
3485 | ip_rt_max_size = (rt_hash_mask + 1) * 16; | |
3486 | ||
1da177e4 LT |
3487 | devinet_init(); |
3488 | ip_fib_init(); | |
3489 | ||
9f28a2fc ED |
3490 | INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func); |
3491 | expires_ljiffies = jiffies; | |
3492 | schedule_delayed_work(&expires_work, | |
3493 | net_random() % ip_rt_gc_interval + ip_rt_gc_interval); | |
3494 | ||
73b38711 | 3495 | if (ip_rt_proc_init()) |
058bd4d2 | 3496 | pr_err("Unable to create route proc files\n"); |
1da177e4 LT |
3497 | #ifdef CONFIG_XFRM |
3498 | xfrm_init(); | |
a33bc5c1 | 3499 | xfrm4_init(ip_rt_max_size); |
1da177e4 | 3500 | #endif |
c7ac8679 | 3501 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL); |
63f3444f | 3502 | |
39a23e75 DL |
3503 | #ifdef CONFIG_SYSCTL |
3504 | register_pernet_subsys(&sysctl_route_ops); | |
3505 | #endif | |
3ee94372 | 3506 | register_pernet_subsys(&rt_genid_ops); |
1da177e4 LT |
3507 | return rc; |
3508 | } | |
3509 | ||
a1bc6eb4 | 3510 | #ifdef CONFIG_SYSCTL |
eeb61f71 AV |
3511 | /* |
3512 | * We really need to sanitize the damn ipv4 init order, then all | |
3513 | * this nonsense will go away. | |
3514 | */ | |
3515 | void __init ip_static_sysctl_init(void) | |
3516 | { | |
2f4520d3 | 3517 | register_sysctl_paths(ipv4_path, ipv4_skeleton); |
eeb61f71 | 3518 | } |
a1bc6eb4 | 3519 | #endif |