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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * ROUTE - implementation of the IP router. | |
7 | * | |
02c30a84 | 8 | * Authors: Ross Biro |
1da177e4 LT |
9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
10 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
11 | * Linus Torvalds, <Linus.Torvalds@helsinki.fi> | |
12 | * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
13 | * | |
14 | * Fixes: | |
15 | * Alan Cox : Verify area fixes. | |
16 | * Alan Cox : cli() protects routing changes | |
17 | * Rui Oliveira : ICMP routing table updates | |
18 | * (rco@di.uminho.pt) Routing table insertion and update | |
19 | * Linus Torvalds : Rewrote bits to be sensible | |
20 | * Alan Cox : Added BSD route gw semantics | |
e905a9ed | 21 | * Alan Cox : Super /proc >4K |
1da177e4 LT |
22 | * Alan Cox : MTU in route table |
23 | * Alan Cox : MSS actually. Also added the window | |
24 | * clamper. | |
25 | * Sam Lantinga : Fixed route matching in rt_del() | |
26 | * Alan Cox : Routing cache support. | |
27 | * Alan Cox : Removed compatibility cruft. | |
28 | * Alan Cox : RTF_REJECT support. | |
29 | * Alan Cox : TCP irtt support. | |
30 | * Jonathan Naylor : Added Metric support. | |
31 | * Miquel van Smoorenburg : BSD API fixes. | |
32 | * Miquel van Smoorenburg : Metrics. | |
33 | * Alan Cox : Use __u32 properly | |
34 | * Alan Cox : Aligned routing errors more closely with BSD | |
35 | * our system is still very different. | |
36 | * Alan Cox : Faster /proc handling | |
37 | * Alexey Kuznetsov : Massive rework to support tree based routing, | |
38 | * routing caches and better behaviour. | |
e905a9ed | 39 | * |
1da177e4 LT |
40 | * Olaf Erb : irtt wasn't being copied right. |
41 | * Bjorn Ekwall : Kerneld route support. | |
42 | * Alan Cox : Multicast fixed (I hope) | |
43 | * Pavel Krauz : Limited broadcast fixed | |
44 | * Mike McLagan : Routing by source | |
45 | * Alexey Kuznetsov : End of old history. Split to fib.c and | |
46 | * route.c and rewritten from scratch. | |
47 | * Andi Kleen : Load-limit warning messages. | |
48 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. | |
49 | * Vitaly E. Lavrov : Race condition in ip_route_input_slow. | |
50 | * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow. | |
51 | * Vladimir V. Ivanov : IP rule info (flowid) is really useful. | |
52 | * Marc Boucher : routing by fwmark | |
53 | * Robert Olsson : Added rt_cache statistics | |
54 | * Arnaldo C. Melo : Convert proc stuff to seq_file | |
bb1d23b0 | 55 | * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes. |
cef2685e IS |
56 | * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect |
57 | * Ilia Sotnikov : Removed TOS from hash calculations | |
1da177e4 LT |
58 | * |
59 | * This program is free software; you can redistribute it and/or | |
60 | * modify it under the terms of the GNU General Public License | |
61 | * as published by the Free Software Foundation; either version | |
62 | * 2 of the License, or (at your option) any later version. | |
63 | */ | |
64 | ||
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> | |
7426a564 | 112 | #include <linux/kmemleak.h> |
1da177e4 | 113 | #endif |
6e5714ea | 114 | #include <net/secure_seq.h> |
1da177e4 | 115 | |
68a5e3dd | 116 | #define RT_FL_TOS(oldflp4) \ |
f61759e6 | 117 | ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) |
1da177e4 LT |
118 | |
119 | #define IP_MAX_MTU 0xFFF0 | |
120 | ||
121 | #define RT_GC_TIMEOUT (300*HZ) | |
122 | ||
1da177e4 | 123 | static int ip_rt_max_size; |
817bc4db | 124 | static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; |
9f28a2fc | 125 | static int ip_rt_gc_interval __read_mostly = 60 * HZ; |
817bc4db SH |
126 | static int ip_rt_gc_min_interval __read_mostly = HZ / 2; |
127 | static int ip_rt_redirect_number __read_mostly = 9; | |
128 | static int ip_rt_redirect_load __read_mostly = HZ / 50; | |
129 | static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); | |
130 | static int ip_rt_error_cost __read_mostly = HZ; | |
131 | static int ip_rt_error_burst __read_mostly = 5 * HZ; | |
132 | static int ip_rt_gc_elasticity __read_mostly = 8; | |
133 | static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; | |
134 | static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; | |
135 | static int ip_rt_min_advmss __read_mostly = 256; | |
1080d709 | 136 | static int rt_chain_length_max __read_mostly = 20; |
1da177e4 | 137 | |
9f28a2fc ED |
138 | static struct delayed_work expires_work; |
139 | static unsigned long expires_ljiffies; | |
140 | ||
1da177e4 LT |
141 | /* |
142 | * Interface to generic destination cache. | |
143 | */ | |
144 | ||
145 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
0dbaee3b | 146 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst); |
ebb762f2 | 147 | static unsigned int ipv4_mtu(const struct dst_entry *dst); |
1da177e4 | 148 | static void ipv4_dst_destroy(struct dst_entry *dst); |
1da177e4 LT |
149 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); |
150 | static void ipv4_link_failure(struct sk_buff *skb); | |
151 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu); | |
569d3645 | 152 | static int rt_garbage_collect(struct dst_ops *ops); |
1da177e4 | 153 | |
72cdd1d9 ED |
154 | static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, |
155 | int how) | |
156 | { | |
157 | } | |
1da177e4 | 158 | |
62fa8a84 DM |
159 | static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) |
160 | { | |
06582540 DM |
161 | struct rtable *rt = (struct rtable *) dst; |
162 | struct inet_peer *peer; | |
163 | u32 *p = NULL; | |
164 | ||
fbfe95a4 | 165 | peer = rt_get_peer_create(rt, rt->rt_dst); |
06582540 | 166 | if (peer) { |
62fa8a84 DM |
167 | u32 *old_p = __DST_METRICS_PTR(old); |
168 | unsigned long prev, new; | |
169 | ||
06582540 DM |
170 | p = peer->metrics; |
171 | if (inet_metrics_new(peer)) | |
172 | memcpy(p, old_p, sizeof(u32) * RTAX_MAX); | |
62fa8a84 DM |
173 | |
174 | new = (unsigned long) p; | |
175 | prev = cmpxchg(&dst->_metrics, old, new); | |
176 | ||
177 | if (prev != old) { | |
62fa8a84 DM |
178 | p = __DST_METRICS_PTR(prev); |
179 | if (prev & DST_METRICS_READ_ONLY) | |
180 | p = NULL; | |
181 | } else { | |
62fa8a84 DM |
182 | if (rt->fi) { |
183 | fib_info_put(rt->fi); | |
184 | rt->fi = NULL; | |
185 | } | |
186 | } | |
187 | } | |
188 | return p; | |
189 | } | |
190 | ||
d3aaeb38 DM |
191 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr); |
192 | ||
1da177e4 LT |
193 | static struct dst_ops ipv4_dst_ops = { |
194 | .family = AF_INET, | |
09640e63 | 195 | .protocol = cpu_to_be16(ETH_P_IP), |
1da177e4 LT |
196 | .gc = rt_garbage_collect, |
197 | .check = ipv4_dst_check, | |
0dbaee3b | 198 | .default_advmss = ipv4_default_advmss, |
ebb762f2 | 199 | .mtu = ipv4_mtu, |
62fa8a84 | 200 | .cow_metrics = ipv4_cow_metrics, |
1da177e4 LT |
201 | .destroy = ipv4_dst_destroy, |
202 | .ifdown = ipv4_dst_ifdown, | |
203 | .negative_advice = ipv4_negative_advice, | |
204 | .link_failure = ipv4_link_failure, | |
205 | .update_pmtu = ip_rt_update_pmtu, | |
1ac06e03 | 206 | .local_out = __ip_local_out, |
d3aaeb38 | 207 | .neigh_lookup = ipv4_neigh_lookup, |
1da177e4 LT |
208 | }; |
209 | ||
210 | #define ECN_OR_COST(class) TC_PRIO_##class | |
211 | ||
4839c52b | 212 | const __u8 ip_tos2prio[16] = { |
1da177e4 | 213 | TC_PRIO_BESTEFFORT, |
4a2b9c37 | 214 | ECN_OR_COST(BESTEFFORT), |
1da177e4 LT |
215 | TC_PRIO_BESTEFFORT, |
216 | ECN_OR_COST(BESTEFFORT), | |
217 | TC_PRIO_BULK, | |
218 | ECN_OR_COST(BULK), | |
219 | TC_PRIO_BULK, | |
220 | ECN_OR_COST(BULK), | |
221 | TC_PRIO_INTERACTIVE, | |
222 | ECN_OR_COST(INTERACTIVE), | |
223 | TC_PRIO_INTERACTIVE, | |
224 | ECN_OR_COST(INTERACTIVE), | |
225 | TC_PRIO_INTERACTIVE_BULK, | |
226 | ECN_OR_COST(INTERACTIVE_BULK), | |
227 | TC_PRIO_INTERACTIVE_BULK, | |
228 | ECN_OR_COST(INTERACTIVE_BULK) | |
229 | }; | |
d4a96865 | 230 | EXPORT_SYMBOL(ip_tos2prio); |
1da177e4 LT |
231 | |
232 | /* | |
233 | * Route cache. | |
234 | */ | |
235 | ||
236 | /* The locking scheme is rather straight forward: | |
237 | * | |
238 | * 1) Read-Copy Update protects the buckets of the central route hash. | |
239 | * 2) Only writers remove entries, and they hold the lock | |
240 | * as they look at rtable reference counts. | |
241 | * 3) Only readers acquire references to rtable entries, | |
242 | * they do so with atomic increments and with the | |
243 | * lock held. | |
244 | */ | |
245 | ||
246 | struct rt_hash_bucket { | |
1c31720a | 247 | struct rtable __rcu *chain; |
22c047cc | 248 | }; |
1080d709 | 249 | |
8a25d5de IM |
250 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ |
251 | defined(CONFIG_PROVE_LOCKING) | |
22c047cc ED |
252 | /* |
253 | * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks | |
254 | * The size of this table is a power of two and depends on the number of CPUS. | |
62051200 | 255 | * (on lockdep we have a quite big spinlock_t, so keep the size down there) |
22c047cc | 256 | */ |
62051200 IM |
257 | #ifdef CONFIG_LOCKDEP |
258 | # define RT_HASH_LOCK_SZ 256 | |
22c047cc | 259 | #else |
62051200 IM |
260 | # if NR_CPUS >= 32 |
261 | # define RT_HASH_LOCK_SZ 4096 | |
262 | # elif NR_CPUS >= 16 | |
263 | # define RT_HASH_LOCK_SZ 2048 | |
264 | # elif NR_CPUS >= 8 | |
265 | # define RT_HASH_LOCK_SZ 1024 | |
266 | # elif NR_CPUS >= 4 | |
267 | # define RT_HASH_LOCK_SZ 512 | |
268 | # else | |
269 | # define RT_HASH_LOCK_SZ 256 | |
270 | # endif | |
22c047cc ED |
271 | #endif |
272 | ||
273 | static spinlock_t *rt_hash_locks; | |
274 | # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)] | |
1ff1cc20 PE |
275 | |
276 | static __init void rt_hash_lock_init(void) | |
277 | { | |
278 | int i; | |
279 | ||
280 | rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ, | |
281 | GFP_KERNEL); | |
282 | if (!rt_hash_locks) | |
283 | panic("IP: failed to allocate rt_hash_locks\n"); | |
284 | ||
285 | for (i = 0; i < RT_HASH_LOCK_SZ; i++) | |
286 | spin_lock_init(&rt_hash_locks[i]); | |
287 | } | |
22c047cc ED |
288 | #else |
289 | # define rt_hash_lock_addr(slot) NULL | |
1ff1cc20 PE |
290 | |
291 | static inline void rt_hash_lock_init(void) | |
292 | { | |
293 | } | |
22c047cc | 294 | #endif |
1da177e4 | 295 | |
817bc4db | 296 | static struct rt_hash_bucket *rt_hash_table __read_mostly; |
95c96174 | 297 | static unsigned int rt_hash_mask __read_mostly; |
817bc4db | 298 | static unsigned int rt_hash_log __read_mostly; |
1da177e4 | 299 | |
2f970d83 | 300 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); |
27f39c73 | 301 | #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field) |
1da177e4 | 302 | |
b00180de | 303 | static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx, |
0eae88f3 | 304 | int genid) |
1da177e4 | 305 | { |
0eae88f3 | 306 | return jhash_3words((__force u32)daddr, (__force u32)saddr, |
b00180de | 307 | idx, genid) |
29e75252 | 308 | & rt_hash_mask; |
1da177e4 LT |
309 | } |
310 | ||
e84f84f2 DL |
311 | static inline int rt_genid(struct net *net) |
312 | { | |
313 | return atomic_read(&net->ipv4.rt_genid); | |
314 | } | |
315 | ||
1da177e4 LT |
316 | #ifdef CONFIG_PROC_FS |
317 | struct rt_cache_iter_state { | |
a75e936f | 318 | struct seq_net_private p; |
1da177e4 | 319 | int bucket; |
29e75252 | 320 | int genid; |
1da177e4 LT |
321 | }; |
322 | ||
1218854a | 323 | static struct rtable *rt_cache_get_first(struct seq_file *seq) |
1da177e4 | 324 | { |
1218854a | 325 | struct rt_cache_iter_state *st = seq->private; |
1da177e4 | 326 | struct rtable *r = NULL; |
1da177e4 LT |
327 | |
328 | for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) { | |
33d480ce | 329 | if (!rcu_access_pointer(rt_hash_table[st->bucket].chain)) |
a6272665 | 330 | continue; |
1da177e4 | 331 | rcu_read_lock_bh(); |
a898def2 | 332 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
29e75252 | 333 | while (r) { |
d8d1f30b | 334 | if (dev_net(r->dst.dev) == seq_file_net(seq) && |
a75e936f | 335 | r->rt_genid == st->genid) |
29e75252 | 336 | return r; |
d8d1f30b | 337 | r = rcu_dereference_bh(r->dst.rt_next); |
29e75252 | 338 | } |
1da177e4 LT |
339 | rcu_read_unlock_bh(); |
340 | } | |
29e75252 | 341 | return r; |
1da177e4 LT |
342 | } |
343 | ||
1218854a | 344 | static struct rtable *__rt_cache_get_next(struct seq_file *seq, |
642d6318 | 345 | struct rtable *r) |
1da177e4 | 346 | { |
1218854a | 347 | struct rt_cache_iter_state *st = seq->private; |
a6272665 | 348 | |
1c31720a | 349 | r = rcu_dereference_bh(r->dst.rt_next); |
1da177e4 LT |
350 | while (!r) { |
351 | rcu_read_unlock_bh(); | |
a6272665 ED |
352 | do { |
353 | if (--st->bucket < 0) | |
354 | return NULL; | |
33d480ce | 355 | } while (!rcu_access_pointer(rt_hash_table[st->bucket].chain)); |
1da177e4 | 356 | rcu_read_lock_bh(); |
1c31720a | 357 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
1da177e4 | 358 | } |
1c31720a | 359 | return r; |
1da177e4 LT |
360 | } |
361 | ||
1218854a | 362 | static struct rtable *rt_cache_get_next(struct seq_file *seq, |
642d6318 DL |
363 | struct rtable *r) |
364 | { | |
1218854a YH |
365 | struct rt_cache_iter_state *st = seq->private; |
366 | while ((r = __rt_cache_get_next(seq, r)) != NULL) { | |
d8d1f30b | 367 | if (dev_net(r->dst.dev) != seq_file_net(seq)) |
a75e936f | 368 | continue; |
642d6318 DL |
369 | if (r->rt_genid == st->genid) |
370 | break; | |
371 | } | |
372 | return r; | |
373 | } | |
374 | ||
1218854a | 375 | static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 376 | { |
1218854a | 377 | struct rtable *r = rt_cache_get_first(seq); |
1da177e4 LT |
378 | |
379 | if (r) | |
1218854a | 380 | while (pos && (r = rt_cache_get_next(seq, r))) |
1da177e4 LT |
381 | --pos; |
382 | return pos ? NULL : r; | |
383 | } | |
384 | ||
385 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) | |
386 | { | |
29e75252 | 387 | struct rt_cache_iter_state *st = seq->private; |
29e75252 | 388 | if (*pos) |
1218854a | 389 | return rt_cache_get_idx(seq, *pos - 1); |
e84f84f2 | 390 | st->genid = rt_genid(seq_file_net(seq)); |
29e75252 | 391 | return SEQ_START_TOKEN; |
1da177e4 LT |
392 | } |
393 | ||
394 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
395 | { | |
29e75252 | 396 | struct rtable *r; |
1da177e4 LT |
397 | |
398 | if (v == SEQ_START_TOKEN) | |
1218854a | 399 | r = rt_cache_get_first(seq); |
1da177e4 | 400 | else |
1218854a | 401 | r = rt_cache_get_next(seq, v); |
1da177e4 LT |
402 | ++*pos; |
403 | return r; | |
404 | } | |
405 | ||
406 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
407 | { | |
408 | if (v && v != SEQ_START_TOKEN) | |
409 | rcu_read_unlock_bh(); | |
410 | } | |
411 | ||
412 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
413 | { | |
414 | if (v == SEQ_START_TOKEN) | |
415 | seq_printf(seq, "%-127s\n", | |
416 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
417 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
418 | "HHUptod\tSpecDst"); | |
419 | else { | |
420 | struct rtable *r = v; | |
69cce1d1 | 421 | struct neighbour *n; |
218fa90f | 422 | int len, HHUptod; |
1da177e4 | 423 | |
218fa90f | 424 | rcu_read_lock(); |
27217455 | 425 | n = dst_get_neighbour_noref(&r->dst); |
218fa90f ED |
426 | HHUptod = (n && (n->nud_state & NUD_CONNECTED)) ? 1 : 0; |
427 | rcu_read_unlock(); | |
428 | ||
0eae88f3 ED |
429 | seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t" |
430 | "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n", | |
d8d1f30b | 431 | r->dst.dev ? r->dst.dev->name : "*", |
0eae88f3 ED |
432 | (__force u32)r->rt_dst, |
433 | (__force u32)r->rt_gateway, | |
d8d1f30b CG |
434 | r->rt_flags, atomic_read(&r->dst.__refcnt), |
435 | r->dst.__use, 0, (__force u32)r->rt_src, | |
0dbaee3b | 436 | dst_metric_advmss(&r->dst) + 40, |
d8d1f30b CG |
437 | dst_metric(&r->dst, RTAX_WINDOW), |
438 | (int)((dst_metric(&r->dst, RTAX_RTT) >> 3) + | |
439 | dst_metric(&r->dst, RTAX_RTTVAR)), | |
475949d8 | 440 | r->rt_key_tos, |
f6b72b62 | 441 | -1, |
218fa90f | 442 | HHUptod, |
5e659e4c PE |
443 | r->rt_spec_dst, &len); |
444 | ||
445 | seq_printf(seq, "%*s\n", 127 - len, ""); | |
e905a9ed YH |
446 | } |
447 | return 0; | |
1da177e4 LT |
448 | } |
449 | ||
f690808e | 450 | static const struct seq_operations rt_cache_seq_ops = { |
1da177e4 LT |
451 | .start = rt_cache_seq_start, |
452 | .next = rt_cache_seq_next, | |
453 | .stop = rt_cache_seq_stop, | |
454 | .show = rt_cache_seq_show, | |
455 | }; | |
456 | ||
457 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
458 | { | |
a75e936f | 459 | return seq_open_net(inode, file, &rt_cache_seq_ops, |
cf7732e4 | 460 | sizeof(struct rt_cache_iter_state)); |
1da177e4 LT |
461 | } |
462 | ||
9a32144e | 463 | static const struct file_operations rt_cache_seq_fops = { |
1da177e4 LT |
464 | .owner = THIS_MODULE, |
465 | .open = rt_cache_seq_open, | |
466 | .read = seq_read, | |
467 | .llseek = seq_lseek, | |
a75e936f | 468 | .release = seq_release_net, |
1da177e4 LT |
469 | }; |
470 | ||
471 | ||
472 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
473 | { | |
474 | int cpu; | |
475 | ||
476 | if (*pos == 0) | |
477 | return SEQ_START_TOKEN; | |
478 | ||
0f23174a | 479 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
480 | if (!cpu_possible(cpu)) |
481 | continue; | |
482 | *pos = cpu+1; | |
2f970d83 | 483 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
484 | } |
485 | return NULL; | |
486 | } | |
487 | ||
488 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
489 | { | |
490 | int cpu; | |
491 | ||
0f23174a | 492 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
493 | if (!cpu_possible(cpu)) |
494 | continue; | |
495 | *pos = cpu+1; | |
2f970d83 | 496 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
497 | } |
498 | return NULL; | |
e905a9ed | 499 | |
1da177e4 LT |
500 | } |
501 | ||
502 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
503 | { | |
504 | ||
505 | } | |
506 | ||
507 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
508 | { | |
509 | struct rt_cache_stat *st = v; | |
510 | ||
511 | if (v == SEQ_START_TOKEN) { | |
5bec0039 | 512 | 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 |
513 | return 0; |
514 | } | |
e905a9ed | 515 | |
1da177e4 LT |
516 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " |
517 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
fc66f95c | 518 | dst_entries_get_slow(&ipv4_dst_ops), |
1da177e4 LT |
519 | st->in_hit, |
520 | st->in_slow_tot, | |
521 | st->in_slow_mc, | |
522 | st->in_no_route, | |
523 | st->in_brd, | |
524 | st->in_martian_dst, | |
525 | st->in_martian_src, | |
526 | ||
527 | st->out_hit, | |
528 | st->out_slow_tot, | |
e905a9ed | 529 | st->out_slow_mc, |
1da177e4 LT |
530 | |
531 | st->gc_total, | |
532 | st->gc_ignored, | |
533 | st->gc_goal_miss, | |
534 | st->gc_dst_overflow, | |
535 | st->in_hlist_search, | |
536 | st->out_hlist_search | |
537 | ); | |
538 | return 0; | |
539 | } | |
540 | ||
f690808e | 541 | static const struct seq_operations rt_cpu_seq_ops = { |
1da177e4 LT |
542 | .start = rt_cpu_seq_start, |
543 | .next = rt_cpu_seq_next, | |
544 | .stop = rt_cpu_seq_stop, | |
545 | .show = rt_cpu_seq_show, | |
546 | }; | |
547 | ||
548 | ||
549 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
550 | { | |
551 | return seq_open(file, &rt_cpu_seq_ops); | |
552 | } | |
553 | ||
9a32144e | 554 | static const struct file_operations rt_cpu_seq_fops = { |
1da177e4 LT |
555 | .owner = THIS_MODULE, |
556 | .open = rt_cpu_seq_open, | |
557 | .read = seq_read, | |
558 | .llseek = seq_lseek, | |
559 | .release = seq_release, | |
560 | }; | |
561 | ||
c7066f70 | 562 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 563 | static int rt_acct_proc_show(struct seq_file *m, void *v) |
78c686e9 | 564 | { |
a661c419 AD |
565 | struct ip_rt_acct *dst, *src; |
566 | unsigned int i, j; | |
567 | ||
568 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
569 | if (!dst) | |
570 | return -ENOMEM; | |
571 | ||
572 | for_each_possible_cpu(i) { | |
573 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
574 | for (j = 0; j < 256; j++) { | |
575 | dst[j].o_bytes += src[j].o_bytes; | |
576 | dst[j].o_packets += src[j].o_packets; | |
577 | dst[j].i_bytes += src[j].i_bytes; | |
578 | dst[j].i_packets += src[j].i_packets; | |
579 | } | |
78c686e9 PE |
580 | } |
581 | ||
a661c419 AD |
582 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); |
583 | kfree(dst); | |
584 | return 0; | |
585 | } | |
78c686e9 | 586 | |
a661c419 AD |
587 | static int rt_acct_proc_open(struct inode *inode, struct file *file) |
588 | { | |
589 | return single_open(file, rt_acct_proc_show, NULL); | |
78c686e9 | 590 | } |
a661c419 AD |
591 | |
592 | static const struct file_operations rt_acct_proc_fops = { | |
593 | .owner = THIS_MODULE, | |
594 | .open = rt_acct_proc_open, | |
595 | .read = seq_read, | |
596 | .llseek = seq_lseek, | |
597 | .release = single_release, | |
598 | }; | |
78c686e9 | 599 | #endif |
107f1634 | 600 | |
73b38711 | 601 | static int __net_init ip_rt_do_proc_init(struct net *net) |
107f1634 PE |
602 | { |
603 | struct proc_dir_entry *pde; | |
604 | ||
605 | pde = proc_net_fops_create(net, "rt_cache", S_IRUGO, | |
606 | &rt_cache_seq_fops); | |
607 | if (!pde) | |
608 | goto err1; | |
609 | ||
77020720 WC |
610 | pde = proc_create("rt_cache", S_IRUGO, |
611 | net->proc_net_stat, &rt_cpu_seq_fops); | |
107f1634 PE |
612 | if (!pde) |
613 | goto err2; | |
614 | ||
c7066f70 | 615 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 616 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); |
107f1634 PE |
617 | if (!pde) |
618 | goto err3; | |
619 | #endif | |
620 | return 0; | |
621 | ||
c7066f70 | 622 | #ifdef CONFIG_IP_ROUTE_CLASSID |
107f1634 PE |
623 | err3: |
624 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
625 | #endif | |
626 | err2: | |
627 | remove_proc_entry("rt_cache", net->proc_net); | |
628 | err1: | |
629 | return -ENOMEM; | |
630 | } | |
73b38711 DL |
631 | |
632 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
633 | { | |
634 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
635 | remove_proc_entry("rt_cache", net->proc_net); | |
c7066f70 | 636 | #ifdef CONFIG_IP_ROUTE_CLASSID |
73b38711 | 637 | remove_proc_entry("rt_acct", net->proc_net); |
0a931acf | 638 | #endif |
73b38711 DL |
639 | } |
640 | ||
641 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
642 | .init = ip_rt_do_proc_init, | |
643 | .exit = ip_rt_do_proc_exit, | |
644 | }; | |
645 | ||
646 | static int __init ip_rt_proc_init(void) | |
647 | { | |
648 | return register_pernet_subsys(&ip_rt_proc_ops); | |
649 | } | |
650 | ||
107f1634 | 651 | #else |
73b38711 | 652 | static inline int ip_rt_proc_init(void) |
107f1634 PE |
653 | { |
654 | return 0; | |
655 | } | |
1da177e4 | 656 | #endif /* CONFIG_PROC_FS */ |
e905a9ed | 657 | |
5969f71d | 658 | static inline void rt_free(struct rtable *rt) |
1da177e4 | 659 | { |
d8d1f30b | 660 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
661 | } |
662 | ||
5969f71d | 663 | static inline void rt_drop(struct rtable *rt) |
1da177e4 | 664 | { |
1da177e4 | 665 | ip_rt_put(rt); |
d8d1f30b | 666 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
667 | } |
668 | ||
5969f71d | 669 | static inline int rt_fast_clean(struct rtable *rth) |
1da177e4 LT |
670 | { |
671 | /* Kill broadcast/multicast entries very aggresively, if they | |
672 | collide in hash table with more useful entries */ | |
673 | return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) && | |
c7537967 | 674 | rt_is_input_route(rth) && rth->dst.rt_next; |
1da177e4 LT |
675 | } |
676 | ||
5969f71d | 677 | static inline int rt_valuable(struct rtable *rth) |
1da177e4 LT |
678 | { |
679 | return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || | |
2c8cec5c | 680 | (rth->peer && rth->peer->pmtu_expires); |
1da177e4 LT |
681 | } |
682 | ||
683 | static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) | |
684 | { | |
685 | unsigned long age; | |
686 | int ret = 0; | |
687 | ||
d8d1f30b | 688 | if (atomic_read(&rth->dst.__refcnt)) |
1da177e4 LT |
689 | goto out; |
690 | ||
d8d1f30b | 691 | age = jiffies - rth->dst.lastuse; |
1da177e4 LT |
692 | if ((age <= tmo1 && !rt_fast_clean(rth)) || |
693 | (age <= tmo2 && rt_valuable(rth))) | |
694 | goto out; | |
695 | ret = 1; | |
696 | out: return ret; | |
697 | } | |
698 | ||
699 | /* Bits of score are: | |
700 | * 31: very valuable | |
701 | * 30: not quite useless | |
702 | * 29..0: usage counter | |
703 | */ | |
704 | static inline u32 rt_score(struct rtable *rt) | |
705 | { | |
d8d1f30b | 706 | u32 score = jiffies - rt->dst.lastuse; |
1da177e4 LT |
707 | |
708 | score = ~score & ~(3<<30); | |
709 | ||
710 | if (rt_valuable(rt)) | |
711 | score |= (1<<31); | |
712 | ||
c7537967 | 713 | if (rt_is_output_route(rt) || |
1da177e4 LT |
714 | !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL))) |
715 | score |= (1<<30); | |
716 | ||
717 | return score; | |
718 | } | |
719 | ||
1080d709 NH |
720 | static inline bool rt_caching(const struct net *net) |
721 | { | |
722 | return net->ipv4.current_rt_cache_rebuild_count <= | |
723 | net->ipv4.sysctl_rt_cache_rebuild_count; | |
724 | } | |
725 | ||
5e2b61f7 DM |
726 | static inline bool compare_hash_inputs(const struct rtable *rt1, |
727 | const struct rtable *rt2) | |
1080d709 | 728 | { |
5e2b61f7 DM |
729 | return ((((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
730 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
97a80410 | 731 | (rt1->rt_route_iif ^ rt2->rt_route_iif)) == 0); |
1080d709 NH |
732 | } |
733 | ||
5e2b61f7 | 734 | static inline int compare_keys(struct rtable *rt1, struct rtable *rt2) |
1da177e4 | 735 | { |
5e2b61f7 DM |
736 | return (((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
737 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
738 | (rt1->rt_mark ^ rt2->rt_mark) | | |
475949d8 | 739 | (rt1->rt_key_tos ^ rt2->rt_key_tos) | |
d547f727 | 740 | (rt1->rt_route_iif ^ rt2->rt_route_iif) | |
97a80410 | 741 | (rt1->rt_oif ^ rt2->rt_oif)) == 0; |
1da177e4 LT |
742 | } |
743 | ||
b5921910 DL |
744 | static inline int compare_netns(struct rtable *rt1, struct rtable *rt2) |
745 | { | |
d8d1f30b | 746 | return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev)); |
b5921910 DL |
747 | } |
748 | ||
e84f84f2 DL |
749 | static inline int rt_is_expired(struct rtable *rth) |
750 | { | |
d8d1f30b | 751 | return rth->rt_genid != rt_genid(dev_net(rth->dst.dev)); |
e84f84f2 DL |
752 | } |
753 | ||
beb659bd ED |
754 | /* |
755 | * Perform a full scan of hash table and free all entries. | |
756 | * Can be called by a softirq or a process. | |
757 | * In the later case, we want to be reschedule if necessary | |
758 | */ | |
6561a3b1 | 759 | static void rt_do_flush(struct net *net, int process_context) |
beb659bd ED |
760 | { |
761 | unsigned int i; | |
762 | struct rtable *rth, *next; | |
763 | ||
764 | for (i = 0; i <= rt_hash_mask; i++) { | |
6561a3b1 DM |
765 | struct rtable __rcu **pprev; |
766 | struct rtable *list; | |
767 | ||
beb659bd ED |
768 | if (process_context && need_resched()) |
769 | cond_resched(); | |
33d480ce | 770 | rth = rcu_access_pointer(rt_hash_table[i].chain); |
beb659bd ED |
771 | if (!rth) |
772 | continue; | |
773 | ||
774 | spin_lock_bh(rt_hash_lock_addr(i)); | |
32cb5b4e | 775 | |
6561a3b1 DM |
776 | list = NULL; |
777 | pprev = &rt_hash_table[i].chain; | |
778 | rth = rcu_dereference_protected(*pprev, | |
1c31720a | 779 | lockdep_is_held(rt_hash_lock_addr(i))); |
32cb5b4e | 780 | |
6561a3b1 DM |
781 | while (rth) { |
782 | next = rcu_dereference_protected(rth->dst.rt_next, | |
1c31720a | 783 | lockdep_is_held(rt_hash_lock_addr(i))); |
6561a3b1 DM |
784 | |
785 | if (!net || | |
786 | net_eq(dev_net(rth->dst.dev), net)) { | |
787 | rcu_assign_pointer(*pprev, next); | |
788 | rcu_assign_pointer(rth->dst.rt_next, list); | |
789 | list = rth; | |
32cb5b4e | 790 | } else { |
6561a3b1 | 791 | pprev = &rth->dst.rt_next; |
32cb5b4e | 792 | } |
6561a3b1 | 793 | rth = next; |
32cb5b4e | 794 | } |
6561a3b1 | 795 | |
beb659bd ED |
796 | spin_unlock_bh(rt_hash_lock_addr(i)); |
797 | ||
6561a3b1 DM |
798 | for (; list; list = next) { |
799 | next = rcu_dereference_protected(list->dst.rt_next, 1); | |
800 | rt_free(list); | |
beb659bd ED |
801 | } |
802 | } | |
803 | } | |
804 | ||
1080d709 NH |
805 | /* |
806 | * While freeing expired entries, we compute average chain length | |
807 | * and standard deviation, using fixed-point arithmetic. | |
808 | * This to have an estimation of rt_chain_length_max | |
809 | * rt_chain_length_max = max(elasticity, AVG + 4*SD) | |
810 | * We use 3 bits for frational part, and 29 (or 61) for magnitude. | |
811 | */ | |
812 | ||
813 | #define FRACT_BITS 3 | |
814 | #define ONE (1UL << FRACT_BITS) | |
815 | ||
98376387 ED |
816 | /* |
817 | * Given a hash chain and an item in this hash chain, | |
818 | * find if a previous entry has the same hash_inputs | |
819 | * (but differs on tos, mark or oif) | |
820 | * Returns 0 if an alias is found. | |
821 | * Returns ONE if rth has no alias before itself. | |
822 | */ | |
823 | static int has_noalias(const struct rtable *head, const struct rtable *rth) | |
824 | { | |
825 | const struct rtable *aux = head; | |
826 | ||
827 | while (aux != rth) { | |
5e2b61f7 | 828 | if (compare_hash_inputs(aux, rth)) |
98376387 | 829 | return 0; |
1c31720a | 830 | aux = rcu_dereference_protected(aux->dst.rt_next, 1); |
98376387 ED |
831 | } |
832 | return ONE; | |
833 | } | |
834 | ||
9f28a2fc ED |
835 | static void rt_check_expire(void) |
836 | { | |
837 | static unsigned int rover; | |
838 | unsigned int i = rover, goal; | |
839 | struct rtable *rth; | |
840 | struct rtable __rcu **rthp; | |
841 | unsigned long samples = 0; | |
842 | unsigned long sum = 0, sum2 = 0; | |
843 | unsigned long delta; | |
844 | u64 mult; | |
845 | ||
846 | delta = jiffies - expires_ljiffies; | |
847 | expires_ljiffies = jiffies; | |
848 | mult = ((u64)delta) << rt_hash_log; | |
849 | if (ip_rt_gc_timeout > 1) | |
850 | do_div(mult, ip_rt_gc_timeout); | |
851 | goal = (unsigned int)mult; | |
852 | if (goal > rt_hash_mask) | |
853 | goal = rt_hash_mask + 1; | |
854 | for (; goal > 0; goal--) { | |
855 | unsigned long tmo = ip_rt_gc_timeout; | |
856 | unsigned long length; | |
857 | ||
858 | i = (i + 1) & rt_hash_mask; | |
859 | rthp = &rt_hash_table[i].chain; | |
860 | ||
861 | if (need_resched()) | |
862 | cond_resched(); | |
863 | ||
864 | samples++; | |
865 | ||
866 | if (rcu_dereference_raw(*rthp) == NULL) | |
867 | continue; | |
868 | length = 0; | |
869 | spin_lock_bh(rt_hash_lock_addr(i)); | |
870 | while ((rth = rcu_dereference_protected(*rthp, | |
871 | lockdep_is_held(rt_hash_lock_addr(i)))) != NULL) { | |
872 | prefetch(rth->dst.rt_next); | |
873 | if (rt_is_expired(rth)) { | |
874 | *rthp = rth->dst.rt_next; | |
875 | rt_free(rth); | |
876 | continue; | |
877 | } | |
878 | if (rth->dst.expires) { | |
879 | /* Entry is expired even if it is in use */ | |
880 | if (time_before_eq(jiffies, rth->dst.expires)) { | |
881 | nofree: | |
882 | tmo >>= 1; | |
883 | rthp = &rth->dst.rt_next; | |
884 | /* | |
885 | * We only count entries on | |
886 | * a chain with equal hash inputs once | |
887 | * so that entries for different QOS | |
888 | * levels, and other non-hash input | |
889 | * attributes don't unfairly skew | |
890 | * the length computation | |
891 | */ | |
892 | length += has_noalias(rt_hash_table[i].chain, rth); | |
893 | continue; | |
894 | } | |
895 | } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) | |
896 | goto nofree; | |
897 | ||
898 | /* Cleanup aged off entries. */ | |
899 | *rthp = rth->dst.rt_next; | |
900 | rt_free(rth); | |
901 | } | |
902 | spin_unlock_bh(rt_hash_lock_addr(i)); | |
903 | sum += length; | |
904 | sum2 += length*length; | |
905 | } | |
906 | if (samples) { | |
907 | unsigned long avg = sum / samples; | |
908 | unsigned long sd = int_sqrt(sum2 / samples - avg*avg); | |
909 | rt_chain_length_max = max_t(unsigned long, | |
910 | ip_rt_gc_elasticity, | |
911 | (avg + 4*sd) >> FRACT_BITS); | |
912 | } | |
913 | rover = i; | |
914 | } | |
915 | ||
916 | /* | |
917 | * rt_worker_func() is run in process context. | |
918 | * we call rt_check_expire() to scan part of the hash table | |
919 | */ | |
920 | static void rt_worker_func(struct work_struct *work) | |
921 | { | |
922 | rt_check_expire(); | |
923 | schedule_delayed_work(&expires_work, ip_rt_gc_interval); | |
924 | } | |
925 | ||
29e75252 | 926 | /* |
25985edc | 927 | * Perturbation of rt_genid by a small quantity [1..256] |
29e75252 ED |
928 | * Using 8 bits of shuffling ensure we can call rt_cache_invalidate() |
929 | * many times (2^24) without giving recent rt_genid. | |
930 | * Jenkins hash is strong enough that litle changes of rt_genid are OK. | |
1da177e4 | 931 | */ |
86c657f6 | 932 | static void rt_cache_invalidate(struct net *net) |
1da177e4 | 933 | { |
29e75252 | 934 | unsigned char shuffle; |
1da177e4 | 935 | |
29e75252 | 936 | get_random_bytes(&shuffle, sizeof(shuffle)); |
e84f84f2 | 937 | atomic_add(shuffle + 1U, &net->ipv4.rt_genid); |
c8a627ed | 938 | inetpeer_invalidate_tree(net, AF_INET); |
1da177e4 LT |
939 | } |
940 | ||
29e75252 ED |
941 | /* |
942 | * delay < 0 : invalidate cache (fast : entries will be deleted later) | |
943 | * delay >= 0 : invalidate & flush cache (can be long) | |
944 | */ | |
76e6ebfb | 945 | void rt_cache_flush(struct net *net, int delay) |
1da177e4 | 946 | { |
86c657f6 | 947 | rt_cache_invalidate(net); |
29e75252 | 948 | if (delay >= 0) |
6561a3b1 | 949 | rt_do_flush(net, !in_softirq()); |
1da177e4 LT |
950 | } |
951 | ||
a5ee1551 | 952 | /* Flush previous cache invalidated entries from the cache */ |
6561a3b1 | 953 | void rt_cache_flush_batch(struct net *net) |
a5ee1551 | 954 | { |
6561a3b1 | 955 | rt_do_flush(net, !in_softirq()); |
a5ee1551 EB |
956 | } |
957 | ||
1080d709 NH |
958 | static void rt_emergency_hash_rebuild(struct net *net) |
959 | { | |
e87cc472 | 960 | net_warn_ratelimited("Route hash chain too long!\n"); |
3ee94372 | 961 | rt_cache_invalidate(net); |
1080d709 NH |
962 | } |
963 | ||
1da177e4 LT |
964 | /* |
965 | Short description of GC goals. | |
966 | ||
967 | We want to build algorithm, which will keep routing cache | |
968 | at some equilibrium point, when number of aged off entries | |
969 | is kept approximately equal to newly generated ones. | |
970 | ||
971 | Current expiration strength is variable "expire". | |
972 | We try to adjust it dynamically, so that if networking | |
973 | is idle expires is large enough to keep enough of warm entries, | |
974 | and when load increases it reduces to limit cache size. | |
975 | */ | |
976 | ||
569d3645 | 977 | static int rt_garbage_collect(struct dst_ops *ops) |
1da177e4 LT |
978 | { |
979 | static unsigned long expire = RT_GC_TIMEOUT; | |
980 | static unsigned long last_gc; | |
981 | static int rover; | |
982 | static int equilibrium; | |
1c31720a ED |
983 | struct rtable *rth; |
984 | struct rtable __rcu **rthp; | |
1da177e4 LT |
985 | unsigned long now = jiffies; |
986 | int goal; | |
fc66f95c | 987 | int entries = dst_entries_get_fast(&ipv4_dst_ops); |
1da177e4 LT |
988 | |
989 | /* | |
990 | * Garbage collection is pretty expensive, | |
991 | * do not make it too frequently. | |
992 | */ | |
993 | ||
994 | RT_CACHE_STAT_INC(gc_total); | |
995 | ||
996 | if (now - last_gc < ip_rt_gc_min_interval && | |
fc66f95c | 997 | entries < ip_rt_max_size) { |
1da177e4 LT |
998 | RT_CACHE_STAT_INC(gc_ignored); |
999 | goto out; | |
1000 | } | |
1001 | ||
fc66f95c | 1002 | entries = dst_entries_get_slow(&ipv4_dst_ops); |
1da177e4 | 1003 | /* Calculate number of entries, which we want to expire now. */ |
fc66f95c | 1004 | goal = entries - (ip_rt_gc_elasticity << rt_hash_log); |
1da177e4 LT |
1005 | if (goal <= 0) { |
1006 | if (equilibrium < ipv4_dst_ops.gc_thresh) | |
1007 | equilibrium = ipv4_dst_ops.gc_thresh; | |
fc66f95c | 1008 | goal = entries - equilibrium; |
1da177e4 | 1009 | if (goal > 0) { |
b790cedd | 1010 | equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 1011 | goal = entries - equilibrium; |
1da177e4 LT |
1012 | } |
1013 | } else { | |
1014 | /* We are in dangerous area. Try to reduce cache really | |
1015 | * aggressively. | |
1016 | */ | |
b790cedd | 1017 | goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 1018 | equilibrium = entries - goal; |
1da177e4 LT |
1019 | } |
1020 | ||
1021 | if (now - last_gc >= ip_rt_gc_min_interval) | |
1022 | last_gc = now; | |
1023 | ||
1024 | if (goal <= 0) { | |
1025 | equilibrium += goal; | |
1026 | goto work_done; | |
1027 | } | |
1028 | ||
1029 | do { | |
1030 | int i, k; | |
1031 | ||
1032 | for (i = rt_hash_mask, k = rover; i >= 0; i--) { | |
1033 | unsigned long tmo = expire; | |
1034 | ||
1035 | k = (k + 1) & rt_hash_mask; | |
1036 | rthp = &rt_hash_table[k].chain; | |
22c047cc | 1037 | spin_lock_bh(rt_hash_lock_addr(k)); |
1c31720a ED |
1038 | while ((rth = rcu_dereference_protected(*rthp, |
1039 | lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) { | |
e84f84f2 | 1040 | if (!rt_is_expired(rth) && |
29e75252 | 1041 | !rt_may_expire(rth, tmo, expire)) { |
1da177e4 | 1042 | tmo >>= 1; |
d8d1f30b | 1043 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1044 | continue; |
1045 | } | |
d8d1f30b | 1046 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1047 | rt_free(rth); |
1048 | goal--; | |
1da177e4 | 1049 | } |
22c047cc | 1050 | spin_unlock_bh(rt_hash_lock_addr(k)); |
1da177e4 LT |
1051 | if (goal <= 0) |
1052 | break; | |
1053 | } | |
1054 | rover = k; | |
1055 | ||
1056 | if (goal <= 0) | |
1057 | goto work_done; | |
1058 | ||
1059 | /* Goal is not achieved. We stop process if: | |
1060 | ||
1061 | - if expire reduced to zero. Otherwise, expire is halfed. | |
1062 | - if table is not full. | |
1063 | - if we are called from interrupt. | |
1064 | - jiffies check is just fallback/debug loop breaker. | |
1065 | We will not spin here for long time in any case. | |
1066 | */ | |
1067 | ||
1068 | RT_CACHE_STAT_INC(gc_goal_miss); | |
1069 | ||
1070 | if (expire == 0) | |
1071 | break; | |
1072 | ||
1073 | expire >>= 1; | |
1da177e4 | 1074 | |
fc66f95c | 1075 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1da177e4 LT |
1076 | goto out; |
1077 | } while (!in_softirq() && time_before_eq(jiffies, now)); | |
1078 | ||
fc66f95c ED |
1079 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1080 | goto out; | |
1081 | if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size) | |
1da177e4 | 1082 | goto out; |
e87cc472 | 1083 | net_warn_ratelimited("dst cache overflow\n"); |
1da177e4 LT |
1084 | RT_CACHE_STAT_INC(gc_dst_overflow); |
1085 | return 1; | |
1086 | ||
1087 | work_done: | |
1088 | expire += ip_rt_gc_min_interval; | |
1089 | if (expire > ip_rt_gc_timeout || | |
fc66f95c ED |
1090 | dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh || |
1091 | dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh) | |
1da177e4 | 1092 | expire = ip_rt_gc_timeout; |
1da177e4 LT |
1093 | out: return 0; |
1094 | } | |
1095 | ||
98376387 ED |
1096 | /* |
1097 | * Returns number of entries in a hash chain that have different hash_inputs | |
1098 | */ | |
1099 | static int slow_chain_length(const struct rtable *head) | |
1100 | { | |
1101 | int length = 0; | |
1102 | const struct rtable *rth = head; | |
1103 | ||
1104 | while (rth) { | |
1105 | length += has_noalias(head, rth); | |
1c31720a | 1106 | rth = rcu_dereference_protected(rth->dst.rt_next, 1); |
98376387 ED |
1107 | } |
1108 | return length >> FRACT_BITS; | |
1109 | } | |
1110 | ||
d3aaeb38 | 1111 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr) |
3769cffb | 1112 | { |
d3aaeb38 DM |
1113 | static const __be32 inaddr_any = 0; |
1114 | struct net_device *dev = dst->dev; | |
1115 | const __be32 *pkey = daddr; | |
39232973 | 1116 | const struct rtable *rt; |
3769cffb DM |
1117 | struct neighbour *n; |
1118 | ||
39232973 DM |
1119 | rt = (const struct rtable *) dst; |
1120 | ||
3769cffb | 1121 | if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) |
d3aaeb38 | 1122 | pkey = &inaddr_any; |
39232973 DM |
1123 | else if (rt->rt_gateway) |
1124 | pkey = (const __be32 *) &rt->rt_gateway; | |
d3aaeb38 | 1125 | |
80703d26 | 1126 | n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey); |
d3aaeb38 DM |
1127 | if (n) |
1128 | return n; | |
32092ecf | 1129 | return neigh_create(&arp_tbl, pkey, dev); |
d3aaeb38 DM |
1130 | } |
1131 | ||
1132 | static int rt_bind_neighbour(struct rtable *rt) | |
1133 | { | |
1134 | struct neighbour *n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway); | |
3769cffb DM |
1135 | if (IS_ERR(n)) |
1136 | return PTR_ERR(n); | |
69cce1d1 | 1137 | dst_set_neighbour(&rt->dst, n); |
3769cffb DM |
1138 | |
1139 | return 0; | |
1140 | } | |
1141 | ||
95c96174 | 1142 | static struct rtable *rt_intern_hash(unsigned int hash, struct rtable *rt, |
b23dd4fe | 1143 | struct sk_buff *skb, int ifindex) |
1da177e4 | 1144 | { |
1c31720a ED |
1145 | struct rtable *rth, *cand; |
1146 | struct rtable __rcu **rthp, **candp; | |
1da177e4 | 1147 | unsigned long now; |
1da177e4 LT |
1148 | u32 min_score; |
1149 | int chain_length; | |
1150 | int attempts = !in_softirq(); | |
1151 | ||
1152 | restart: | |
1153 | chain_length = 0; | |
1154 | min_score = ~(u32)0; | |
1155 | cand = NULL; | |
1156 | candp = NULL; | |
1157 | now = jiffies; | |
1158 | ||
d8d1f30b | 1159 | if (!rt_caching(dev_net(rt->dst.dev))) { |
73e42897 NH |
1160 | /* |
1161 | * If we're not caching, just tell the caller we | |
1162 | * were successful and don't touch the route. The | |
1163 | * caller hold the sole reference to the cache entry, and | |
1164 | * it will be released when the caller is done with it. | |
1165 | * If we drop it here, the callers have no way to resolve routes | |
1166 | * when we're not caching. Instead, just point *rp at rt, so | |
1167 | * the caller gets a single use out of the route | |
b6280b47 NH |
1168 | * Note that we do rt_free on this new route entry, so that |
1169 | * once its refcount hits zero, we are still able to reap it | |
1170 | * (Thanks Alexey) | |
27b75c95 ED |
1171 | * Note: To avoid expensive rcu stuff for this uncached dst, |
1172 | * we set DST_NOCACHE so that dst_release() can free dst without | |
1173 | * waiting a grace period. | |
73e42897 | 1174 | */ |
b6280b47 | 1175 | |
c7d4426a | 1176 | rt->dst.flags |= DST_NOCACHE; |
c7537967 | 1177 | if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) { |
3769cffb | 1178 | int err = rt_bind_neighbour(rt); |
b6280b47 | 1179 | if (err) { |
e87cc472 | 1180 | net_warn_ratelimited("Neighbour table failure & not caching routes\n"); |
27b75c95 | 1181 | ip_rt_put(rt); |
b23dd4fe | 1182 | return ERR_PTR(err); |
b6280b47 NH |
1183 | } |
1184 | } | |
1185 | ||
b6280b47 | 1186 | goto skip_hashing; |
1080d709 NH |
1187 | } |
1188 | ||
1da177e4 LT |
1189 | rthp = &rt_hash_table[hash].chain; |
1190 | ||
22c047cc | 1191 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1c31720a ED |
1192 | while ((rth = rcu_dereference_protected(*rthp, |
1193 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1194 | if (rt_is_expired(rth)) { |
d8d1f30b | 1195 | *rthp = rth->dst.rt_next; |
29e75252 ED |
1196 | rt_free(rth); |
1197 | continue; | |
1198 | } | |
5e2b61f7 | 1199 | if (compare_keys(rth, rt) && compare_netns(rth, rt)) { |
1da177e4 | 1200 | /* Put it first */ |
d8d1f30b | 1201 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1202 | /* |
1203 | * Since lookup is lockfree, the deletion | |
1204 | * must be visible to another weakly ordered CPU before | |
1205 | * the insertion at the start of the hash chain. | |
1206 | */ | |
d8d1f30b | 1207 | rcu_assign_pointer(rth->dst.rt_next, |
1da177e4 LT |
1208 | rt_hash_table[hash].chain); |
1209 | /* | |
1210 | * Since lookup is lockfree, the update writes | |
1211 | * must be ordered for consistency on SMP. | |
1212 | */ | |
1213 | rcu_assign_pointer(rt_hash_table[hash].chain, rth); | |
1214 | ||
d8d1f30b | 1215 | dst_use(&rth->dst, now); |
22c047cc | 1216 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1217 | |
1218 | rt_drop(rt); | |
b23dd4fe | 1219 | if (skb) |
d8d1f30b | 1220 | skb_dst_set(skb, &rth->dst); |
b23dd4fe | 1221 | return rth; |
1da177e4 LT |
1222 | } |
1223 | ||
d8d1f30b | 1224 | if (!atomic_read(&rth->dst.__refcnt)) { |
1da177e4 LT |
1225 | u32 score = rt_score(rth); |
1226 | ||
1227 | if (score <= min_score) { | |
1228 | cand = rth; | |
1229 | candp = rthp; | |
1230 | min_score = score; | |
1231 | } | |
1232 | } | |
1233 | ||
1234 | chain_length++; | |
1235 | ||
d8d1f30b | 1236 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1237 | } |
1238 | ||
1239 | if (cand) { | |
1240 | /* ip_rt_gc_elasticity used to be average length of chain | |
1241 | * length, when exceeded gc becomes really aggressive. | |
1242 | * | |
1243 | * The second limit is less certain. At the moment it allows | |
1244 | * only 2 entries per bucket. We will see. | |
1245 | */ | |
1246 | if (chain_length > ip_rt_gc_elasticity) { | |
d8d1f30b | 1247 | *candp = cand->dst.rt_next; |
1da177e4 LT |
1248 | rt_free(cand); |
1249 | } | |
1080d709 | 1250 | } else { |
98376387 ED |
1251 | if (chain_length > rt_chain_length_max && |
1252 | slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) { | |
d8d1f30b | 1253 | struct net *net = dev_net(rt->dst.dev); |
1080d709 | 1254 | int num = ++net->ipv4.current_rt_cache_rebuild_count; |
b35ecb5d | 1255 | if (!rt_caching(net)) { |
058bd4d2 | 1256 | pr_warn("%s: %d rebuilds is over limit, route caching disabled\n", |
d8d1f30b | 1257 | rt->dst.dev->name, num); |
1080d709 | 1258 | } |
b35ecb5d | 1259 | rt_emergency_hash_rebuild(net); |
6a2bad70 PE |
1260 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1261 | ||
5e2b61f7 | 1262 | hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
6a2bad70 PE |
1263 | ifindex, rt_genid(net)); |
1264 | goto restart; | |
1080d709 | 1265 | } |
1da177e4 LT |
1266 | } |
1267 | ||
1268 | /* Try to bind route to arp only if it is output | |
1269 | route or unicast forwarding path. | |
1270 | */ | |
c7537967 | 1271 | if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) { |
3769cffb | 1272 | int err = rt_bind_neighbour(rt); |
1da177e4 | 1273 | if (err) { |
22c047cc | 1274 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1275 | |
1276 | if (err != -ENOBUFS) { | |
1277 | rt_drop(rt); | |
b23dd4fe | 1278 | return ERR_PTR(err); |
1da177e4 LT |
1279 | } |
1280 | ||
1281 | /* Neighbour tables are full and nothing | |
1282 | can be released. Try to shrink route cache, | |
1283 | it is most likely it holds some neighbour records. | |
1284 | */ | |
1285 | if (attempts-- > 0) { | |
1286 | int saved_elasticity = ip_rt_gc_elasticity; | |
1287 | int saved_int = ip_rt_gc_min_interval; | |
1288 | ip_rt_gc_elasticity = 1; | |
1289 | ip_rt_gc_min_interval = 0; | |
569d3645 | 1290 | rt_garbage_collect(&ipv4_dst_ops); |
1da177e4 LT |
1291 | ip_rt_gc_min_interval = saved_int; |
1292 | ip_rt_gc_elasticity = saved_elasticity; | |
1293 | goto restart; | |
1294 | } | |
1295 | ||
e87cc472 | 1296 | net_warn_ratelimited("Neighbour table overflow\n"); |
1da177e4 | 1297 | rt_drop(rt); |
b23dd4fe | 1298 | return ERR_PTR(-ENOBUFS); |
1da177e4 LT |
1299 | } |
1300 | } | |
1301 | ||
d8d1f30b | 1302 | rt->dst.rt_next = rt_hash_table[hash].chain; |
1080d709 | 1303 | |
00269b54 ED |
1304 | /* |
1305 | * Since lookup is lockfree, we must make sure | |
25985edc | 1306 | * previous writes to rt are committed to memory |
00269b54 ED |
1307 | * before making rt visible to other CPUS. |
1308 | */ | |
1ddbcb00 | 1309 | rcu_assign_pointer(rt_hash_table[hash].chain, rt); |
1080d709 | 1310 | |
22c047cc | 1311 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
73e42897 | 1312 | |
b6280b47 | 1313 | skip_hashing: |
b23dd4fe | 1314 | if (skb) |
d8d1f30b | 1315 | skb_dst_set(skb, &rt->dst); |
b23dd4fe | 1316 | return rt; |
1da177e4 LT |
1317 | } |
1318 | ||
6431cbc2 DM |
1319 | static atomic_t __rt_peer_genid = ATOMIC_INIT(0); |
1320 | ||
1321 | static u32 rt_peer_genid(void) | |
1322 | { | |
1323 | return atomic_read(&__rt_peer_genid); | |
1324 | } | |
1325 | ||
a48eff12 | 1326 | void rt_bind_peer(struct rtable *rt, __be32 daddr, int create) |
1da177e4 | 1327 | { |
54db0cc2 | 1328 | struct net *net = dev_net(rt->dst.dev); |
1da177e4 LT |
1329 | struct inet_peer *peer; |
1330 | ||
54db0cc2 | 1331 | peer = inet_getpeer_v4(net, daddr, create); |
1da177e4 | 1332 | |
49e8ab03 | 1333 | if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL) |
1da177e4 | 1334 | inet_putpeer(peer); |
6431cbc2 DM |
1335 | else |
1336 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 LT |
1337 | } |
1338 | ||
1339 | /* | |
1340 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
1341 | * we still can generate some output. | |
1342 | * Random ID selection looks a bit dangerous because we have no chances to | |
1343 | * select ID being unique in a reasonable period of time. | |
1344 | * But broken packet identifier may be better than no packet at all. | |
1345 | */ | |
1346 | static void ip_select_fb_ident(struct iphdr *iph) | |
1347 | { | |
1348 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
1349 | static u32 ip_fallback_id; | |
1350 | u32 salt; | |
1351 | ||
1352 | spin_lock_bh(&ip_fb_id_lock); | |
e448515c | 1353 | salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr); |
1da177e4 LT |
1354 | iph->id = htons(salt & 0xFFFF); |
1355 | ip_fallback_id = salt; | |
1356 | spin_unlock_bh(&ip_fb_id_lock); | |
1357 | } | |
1358 | ||
1359 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
1360 | { | |
1361 | struct rtable *rt = (struct rtable *) dst; | |
1362 | ||
e688a604 | 1363 | if (rt && !(rt->dst.flags & DST_NOPEER)) { |
fbfe95a4 | 1364 | struct inet_peer *peer = rt_get_peer_create(rt, rt->rt_dst); |
1da177e4 LT |
1365 | |
1366 | /* If peer is attached to destination, it is never detached, | |
1367 | so that we need not to grab a lock to dereference it. | |
1368 | */ | |
fbfe95a4 DM |
1369 | if (peer) { |
1370 | iph->id = htons(inet_getid(peer, more)); | |
1da177e4 LT |
1371 | return; |
1372 | } | |
e688a604 | 1373 | } else if (!rt) |
91df42be | 1374 | pr_debug("rt_bind_peer(0) @%p\n", __builtin_return_address(0)); |
1da177e4 LT |
1375 | |
1376 | ip_select_fb_ident(iph); | |
1377 | } | |
4bc2f18b | 1378 | EXPORT_SYMBOL(__ip_select_ident); |
1da177e4 | 1379 | |
95c96174 | 1380 | static void rt_del(unsigned int hash, struct rtable *rt) |
1da177e4 | 1381 | { |
1c31720a ED |
1382 | struct rtable __rcu **rthp; |
1383 | struct rtable *aux; | |
1da177e4 | 1384 | |
29e75252 | 1385 | rthp = &rt_hash_table[hash].chain; |
22c047cc | 1386 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1da177e4 | 1387 | ip_rt_put(rt); |
1c31720a ED |
1388 | while ((aux = rcu_dereference_protected(*rthp, |
1389 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1390 | if (aux == rt || rt_is_expired(aux)) { |
d8d1f30b | 1391 | *rthp = aux->dst.rt_next; |
29e75252 ED |
1392 | rt_free(aux); |
1393 | continue; | |
1da177e4 | 1394 | } |
d8d1f30b | 1395 | rthp = &aux->dst.rt_next; |
29e75252 | 1396 | } |
22c047cc | 1397 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1398 | } |
1399 | ||
de398fb8 | 1400 | static void check_peer_redir(struct dst_entry *dst, struct inet_peer *peer) |
9cc20b26 ED |
1401 | { |
1402 | struct rtable *rt = (struct rtable *) dst; | |
1403 | __be32 orig_gw = rt->rt_gateway; | |
1404 | struct neighbour *n, *old_n; | |
1405 | ||
1406 | dst_confirm(&rt->dst); | |
1407 | ||
1408 | rt->rt_gateway = peer->redirect_learned.a4; | |
1409 | ||
1410 | n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway); | |
de398fb8 DM |
1411 | if (IS_ERR(n)) { |
1412 | rt->rt_gateway = orig_gw; | |
1413 | return; | |
1414 | } | |
9cc20b26 ED |
1415 | old_n = xchg(&rt->dst._neighbour, n); |
1416 | if (old_n) | |
1417 | neigh_release(old_n); | |
de398fb8 DM |
1418 | if (!(n->nud_state & NUD_VALID)) { |
1419 | neigh_event_send(n, NULL); | |
9cc20b26 ED |
1420 | } else { |
1421 | rt->rt_flags |= RTCF_REDIRECTED; | |
1422 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); | |
1423 | } | |
9cc20b26 ED |
1424 | } |
1425 | ||
ed7865a4 | 1426 | /* called in rcu_read_lock() section */ |
f7655229 AV |
1427 | void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, |
1428 | __be32 saddr, struct net_device *dev) | |
1da177e4 | 1429 | { |
7cc9150e | 1430 | int s, i; |
ed7865a4 | 1431 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
7cc9150e FL |
1432 | __be32 skeys[2] = { saddr, 0 }; |
1433 | int ikeys[2] = { dev->ifindex, 0 }; | |
f39925db | 1434 | struct inet_peer *peer; |
317805b8 | 1435 | struct net *net; |
1da177e4 | 1436 | |
1da177e4 LT |
1437 | if (!in_dev) |
1438 | return; | |
1439 | ||
c346dca1 | 1440 | net = dev_net(dev); |
9d4fb27d JP |
1441 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || |
1442 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
1443 | ipv4_is_zeronet(new_gw)) | |
1da177e4 LT |
1444 | goto reject_redirect; |
1445 | ||
1446 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
1447 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
1448 | goto reject_redirect; | |
1449 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
1450 | goto reject_redirect; | |
1451 | } else { | |
317805b8 | 1452 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) |
1da177e4 LT |
1453 | goto reject_redirect; |
1454 | } | |
1455 | ||
7cc9150e FL |
1456 | for (s = 0; s < 2; s++) { |
1457 | for (i = 0; i < 2; i++) { | |
9cc20b26 ED |
1458 | unsigned int hash; |
1459 | struct rtable __rcu **rthp; | |
1460 | struct rtable *rt; | |
1461 | ||
1462 | hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net)); | |
1463 | ||
1464 | rthp = &rt_hash_table[hash].chain; | |
1465 | ||
1466 | while ((rt = rcu_dereference(*rthp)) != NULL) { | |
1467 | rthp = &rt->dst.rt_next; | |
1468 | ||
1469 | if (rt->rt_key_dst != daddr || | |
1470 | rt->rt_key_src != skeys[s] || | |
1471 | rt->rt_oif != ikeys[i] || | |
1472 | rt_is_input_route(rt) || | |
1473 | rt_is_expired(rt) || | |
1474 | !net_eq(dev_net(rt->dst.dev), net) || | |
1475 | rt->dst.error || | |
1476 | rt->dst.dev != dev || | |
1477 | rt->rt_gateway != old_gw) | |
1478 | continue; | |
e905a9ed | 1479 | |
fbfe95a4 | 1480 | peer = rt_get_peer_create(rt, rt->rt_dst); |
9cc20b26 | 1481 | if (peer) { |
ac3f48de | 1482 | if (peer->redirect_learned.a4 != new_gw) { |
9cc20b26 ED |
1483 | peer->redirect_learned.a4 = new_gw; |
1484 | atomic_inc(&__rt_peer_genid); | |
1485 | } | |
1486 | check_peer_redir(&rt->dst, peer); | |
1487 | } | |
7cc9150e | 1488 | } |
7cc9150e | 1489 | } |
1da177e4 | 1490 | } |
1da177e4 LT |
1491 | return; |
1492 | ||
1493 | reject_redirect: | |
1494 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
e87cc472 JP |
1495 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
1496 | net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n" | |
1497 | " Advised path = %pI4 -> %pI4\n", | |
1498 | &old_gw, dev->name, &new_gw, | |
1499 | &saddr, &daddr); | |
1da177e4 | 1500 | #endif |
ed7865a4 | 1501 | ; |
1da177e4 LT |
1502 | } |
1503 | ||
fe6fe792 ED |
1504 | static bool peer_pmtu_expired(struct inet_peer *peer) |
1505 | { | |
1506 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1507 | ||
1508 | return orig && | |
1509 | time_after_eq(jiffies, orig) && | |
1510 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1511 | } | |
1512 | ||
1513 | static bool peer_pmtu_cleaned(struct inet_peer *peer) | |
1514 | { | |
1515 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1516 | ||
1517 | return orig && | |
1518 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1519 | } | |
1520 | ||
1da177e4 LT |
1521 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) |
1522 | { | |
ee6b9673 | 1523 | struct rtable *rt = (struct rtable *)dst; |
1da177e4 LT |
1524 | struct dst_entry *ret = dst; |
1525 | ||
1526 | if (rt) { | |
d11a4dc1 | 1527 | if (dst->obsolete > 0) { |
1da177e4 LT |
1528 | ip_rt_put(rt); |
1529 | ret = NULL; | |
2c8cec5c | 1530 | } else if (rt->rt_flags & RTCF_REDIRECTED) { |
95c96174 | 1531 | unsigned int hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
5e2b61f7 | 1532 | rt->rt_oif, |
e84f84f2 | 1533 | rt_genid(dev_net(dst->dev))); |
1da177e4 LT |
1534 | rt_del(hash, rt); |
1535 | ret = NULL; | |
fe6fe792 ED |
1536 | } else if (rt->peer && peer_pmtu_expired(rt->peer)) { |
1537 | dst_metric_set(dst, RTAX_MTU, rt->peer->pmtu_orig); | |
1da177e4 LT |
1538 | } |
1539 | } | |
1540 | return ret; | |
1541 | } | |
1542 | ||
1543 | /* | |
1544 | * Algorithm: | |
1545 | * 1. The first ip_rt_redirect_number redirects are sent | |
1546 | * with exponential backoff, then we stop sending them at all, | |
1547 | * assuming that the host ignores our redirects. | |
1548 | * 2. If we did not see packets requiring redirects | |
1549 | * during ip_rt_redirect_silence, we assume that the host | |
1550 | * forgot redirected route and start to send redirects again. | |
1551 | * | |
1552 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
1553 | * in icmp.c. | |
1554 | * | |
1555 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
1556 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
1557 | */ | |
1558 | ||
1559 | void ip_rt_send_redirect(struct sk_buff *skb) | |
1560 | { | |
511c3f92 | 1561 | struct rtable *rt = skb_rtable(skb); |
30038fc6 | 1562 | struct in_device *in_dev; |
92d86829 | 1563 | struct inet_peer *peer; |
30038fc6 | 1564 | int log_martians; |
1da177e4 | 1565 | |
30038fc6 | 1566 | rcu_read_lock(); |
d8d1f30b | 1567 | in_dev = __in_dev_get_rcu(rt->dst.dev); |
30038fc6 ED |
1568 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { |
1569 | rcu_read_unlock(); | |
1da177e4 | 1570 | return; |
30038fc6 ED |
1571 | } |
1572 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
1573 | rcu_read_unlock(); | |
1da177e4 | 1574 | |
fbfe95a4 | 1575 | peer = rt_get_peer_create(rt, rt->rt_dst); |
92d86829 DM |
1576 | if (!peer) { |
1577 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
1578 | return; | |
1579 | } | |
1580 | ||
1da177e4 LT |
1581 | /* No redirected packets during ip_rt_redirect_silence; |
1582 | * reset the algorithm. | |
1583 | */ | |
92d86829 DM |
1584 | if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) |
1585 | peer->rate_tokens = 0; | |
1da177e4 LT |
1586 | |
1587 | /* Too many ignored redirects; do not send anything | |
d8d1f30b | 1588 | * set dst.rate_last to the last seen redirected packet. |
1da177e4 | 1589 | */ |
92d86829 DM |
1590 | if (peer->rate_tokens >= ip_rt_redirect_number) { |
1591 | peer->rate_last = jiffies; | |
30038fc6 | 1592 | return; |
1da177e4 LT |
1593 | } |
1594 | ||
1595 | /* Check for load limit; set rate_last to the latest sent | |
1596 | * redirect. | |
1597 | */ | |
92d86829 | 1598 | if (peer->rate_tokens == 0 || |
14fb8a76 | 1599 | time_after(jiffies, |
92d86829 DM |
1600 | (peer->rate_last + |
1601 | (ip_rt_redirect_load << peer->rate_tokens)))) { | |
1da177e4 | 1602 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); |
92d86829 DM |
1603 | peer->rate_last = jiffies; |
1604 | ++peer->rate_tokens; | |
1da177e4 | 1605 | #ifdef CONFIG_IP_ROUTE_VERBOSE |
30038fc6 | 1606 | if (log_martians && |
e87cc472 JP |
1607 | peer->rate_tokens == ip_rt_redirect_number) |
1608 | net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", | |
1609 | &ip_hdr(skb)->saddr, rt->rt_iif, | |
1610 | &rt->rt_dst, &rt->rt_gateway); | |
1da177e4 LT |
1611 | #endif |
1612 | } | |
1da177e4 LT |
1613 | } |
1614 | ||
1615 | static int ip_error(struct sk_buff *skb) | |
1616 | { | |
511c3f92 | 1617 | struct rtable *rt = skb_rtable(skb); |
92d86829 | 1618 | struct inet_peer *peer; |
1da177e4 | 1619 | unsigned long now; |
92d86829 | 1620 | bool send; |
1da177e4 LT |
1621 | int code; |
1622 | ||
d8d1f30b | 1623 | switch (rt->dst.error) { |
4500ebf8 JP |
1624 | case EINVAL: |
1625 | default: | |
1626 | goto out; | |
1627 | case EHOSTUNREACH: | |
1628 | code = ICMP_HOST_UNREACH; | |
1629 | break; | |
1630 | case ENETUNREACH: | |
1631 | code = ICMP_NET_UNREACH; | |
1632 | IP_INC_STATS_BH(dev_net(rt->dst.dev), | |
1633 | IPSTATS_MIB_INNOROUTES); | |
1634 | break; | |
1635 | case EACCES: | |
1636 | code = ICMP_PKT_FILTERED; | |
1637 | break; | |
1da177e4 LT |
1638 | } |
1639 | ||
fbfe95a4 | 1640 | peer = rt_get_peer_create(rt, rt->rt_dst); |
92d86829 DM |
1641 | |
1642 | send = true; | |
1643 | if (peer) { | |
1644 | now = jiffies; | |
1645 | peer->rate_tokens += now - peer->rate_last; | |
1646 | if (peer->rate_tokens > ip_rt_error_burst) | |
1647 | peer->rate_tokens = ip_rt_error_burst; | |
1648 | peer->rate_last = now; | |
1649 | if (peer->rate_tokens >= ip_rt_error_cost) | |
1650 | peer->rate_tokens -= ip_rt_error_cost; | |
1651 | else | |
1652 | send = false; | |
1da177e4 | 1653 | } |
92d86829 DM |
1654 | if (send) |
1655 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1da177e4 LT |
1656 | |
1657 | out: kfree_skb(skb); | |
1658 | return 0; | |
e905a9ed | 1659 | } |
1da177e4 LT |
1660 | |
1661 | /* | |
1662 | * The last two values are not from the RFC but | |
1663 | * are needed for AMPRnet AX.25 paths. | |
1664 | */ | |
1665 | ||
9b5b5cff | 1666 | static const unsigned short mtu_plateau[] = |
1da177e4 LT |
1667 | {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 }; |
1668 | ||
5969f71d | 1669 | static inline unsigned short guess_mtu(unsigned short old_mtu) |
1da177e4 LT |
1670 | { |
1671 | int i; | |
e905a9ed | 1672 | |
1da177e4 LT |
1673 | for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++) |
1674 | if (old_mtu > mtu_plateau[i]) | |
1675 | return mtu_plateau[i]; | |
1676 | return 68; | |
1677 | } | |
1678 | ||
b71d1d42 | 1679 | unsigned short ip_rt_frag_needed(struct net *net, const struct iphdr *iph, |
0010e465 TT |
1680 | unsigned short new_mtu, |
1681 | struct net_device *dev) | |
1da177e4 | 1682 | { |
1da177e4 | 1683 | unsigned short old_mtu = ntohs(iph->tot_len); |
1da177e4 | 1684 | unsigned short est_mtu = 0; |
2c8cec5c | 1685 | struct inet_peer *peer; |
1da177e4 | 1686 | |
54db0cc2 | 1687 | peer = inet_getpeer_v4(net, iph->daddr, 1); |
2c8cec5c DM |
1688 | if (peer) { |
1689 | unsigned short mtu = new_mtu; | |
1da177e4 | 1690 | |
2c8cec5c DM |
1691 | if (new_mtu < 68 || new_mtu >= old_mtu) { |
1692 | /* BSD 4.2 derived systems incorrectly adjust | |
1693 | * tot_len by the IP header length, and report | |
1694 | * a zero MTU in the ICMP message. | |
1695 | */ | |
1696 | if (mtu == 0 && | |
1697 | old_mtu >= 68 + (iph->ihl << 2)) | |
1698 | old_mtu -= iph->ihl << 2; | |
1699 | mtu = guess_mtu(old_mtu); | |
1700 | } | |
0010e465 | 1701 | |
2c8cec5c DM |
1702 | if (mtu < ip_rt_min_pmtu) |
1703 | mtu = ip_rt_min_pmtu; | |
1704 | if (!peer->pmtu_expires || mtu < peer->pmtu_learned) { | |
46af3180 HS |
1705 | unsigned long pmtu_expires; |
1706 | ||
1707 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1708 | if (!pmtu_expires) | |
1709 | pmtu_expires = 1UL; | |
1710 | ||
2c8cec5c DM |
1711 | est_mtu = mtu; |
1712 | peer->pmtu_learned = mtu; | |
46af3180 | 1713 | peer->pmtu_expires = pmtu_expires; |
59445b6b | 1714 | atomic_inc(&__rt_peer_genid); |
2c8cec5c | 1715 | } |
1da177e4 | 1716 | |
2c8cec5c | 1717 | inet_putpeer(peer); |
1da177e4 LT |
1718 | } |
1719 | return est_mtu ? : new_mtu; | |
1720 | } | |
1721 | ||
2c8cec5c DM |
1722 | static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer) |
1723 | { | |
fe6fe792 | 1724 | unsigned long expires = ACCESS_ONCE(peer->pmtu_expires); |
2c8cec5c | 1725 | |
fe6fe792 ED |
1726 | if (!expires) |
1727 | return; | |
46af3180 | 1728 | if (time_before(jiffies, expires)) { |
2c8cec5c DM |
1729 | u32 orig_dst_mtu = dst_mtu(dst); |
1730 | if (peer->pmtu_learned < orig_dst_mtu) { | |
1731 | if (!peer->pmtu_orig) | |
1732 | peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU); | |
1733 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned); | |
1734 | } | |
1735 | } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires) | |
1736 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); | |
1737 | } | |
1738 | ||
1da177e4 LT |
1739 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) |
1740 | { | |
2c8cec5c DM |
1741 | struct rtable *rt = (struct rtable *) dst; |
1742 | struct inet_peer *peer; | |
1743 | ||
1744 | dst_confirm(dst); | |
1745 | ||
fbfe95a4 | 1746 | peer = rt_get_peer_create(rt, rt->rt_dst); |
2c8cec5c | 1747 | if (peer) { |
fe6fe792 ED |
1748 | unsigned long pmtu_expires = ACCESS_ONCE(peer->pmtu_expires); |
1749 | ||
2c8cec5c | 1750 | if (mtu < ip_rt_min_pmtu) |
1da177e4 | 1751 | mtu = ip_rt_min_pmtu; |
fe6fe792 | 1752 | if (!pmtu_expires || mtu < peer->pmtu_learned) { |
46af3180 HS |
1753 | |
1754 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1755 | if (!pmtu_expires) | |
1756 | pmtu_expires = 1UL; | |
1757 | ||
2c8cec5c | 1758 | peer->pmtu_learned = mtu; |
46af3180 | 1759 | peer->pmtu_expires = pmtu_expires; |
2c8cec5c DM |
1760 | |
1761 | atomic_inc(&__rt_peer_genid); | |
1762 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 | 1763 | } |
46af3180 | 1764 | check_peer_pmtu(dst, peer); |
1da177e4 LT |
1765 | } |
1766 | } | |
1767 | ||
f39925db | 1768 | |
de398fb8 | 1769 | static void ipv4_validate_peer(struct rtable *rt) |
1da177e4 | 1770 | { |
6431cbc2 | 1771 | if (rt->rt_peer_genid != rt_peer_genid()) { |
fbfe95a4 | 1772 | struct inet_peer *peer = rt_get_peer(rt, rt->rt_dst); |
6431cbc2 | 1773 | |
fe6fe792 | 1774 | if (peer) { |
efbc368d | 1775 | check_peer_pmtu(&rt->dst, peer); |
2c8cec5c | 1776 | |
fe6fe792 | 1777 | if (peer->redirect_learned.a4 && |
de398fb8 DM |
1778 | peer->redirect_learned.a4 != rt->rt_gateway) |
1779 | check_peer_redir(&rt->dst, peer); | |
f39925db DM |
1780 | } |
1781 | ||
6431cbc2 DM |
1782 | rt->rt_peer_genid = rt_peer_genid(); |
1783 | } | |
efbc368d DM |
1784 | } |
1785 | ||
1786 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) | |
1787 | { | |
1788 | struct rtable *rt = (struct rtable *) dst; | |
1789 | ||
1790 | if (rt_is_expired(rt)) | |
1791 | return NULL; | |
de398fb8 | 1792 | ipv4_validate_peer(rt); |
d11a4dc1 | 1793 | return dst; |
1da177e4 LT |
1794 | } |
1795 | ||
1796 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1797 | { | |
1798 | struct rtable *rt = (struct rtable *) dst; | |
1799 | struct inet_peer *peer = rt->peer; | |
1da177e4 | 1800 | |
62fa8a84 DM |
1801 | if (rt->fi) { |
1802 | fib_info_put(rt->fi); | |
1803 | rt->fi = NULL; | |
1804 | } | |
1da177e4 LT |
1805 | if (peer) { |
1806 | rt->peer = NULL; | |
1807 | inet_putpeer(peer); | |
1808 | } | |
1da177e4 LT |
1809 | } |
1810 | ||
1da177e4 LT |
1811 | |
1812 | static void ipv4_link_failure(struct sk_buff *skb) | |
1813 | { | |
1814 | struct rtable *rt; | |
1815 | ||
1816 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1817 | ||
511c3f92 | 1818 | rt = skb_rtable(skb); |
fe6fe792 ED |
1819 | if (rt && rt->peer && peer_pmtu_cleaned(rt->peer)) |
1820 | dst_metric_set(&rt->dst, RTAX_MTU, rt->peer->pmtu_orig); | |
1da177e4 LT |
1821 | } |
1822 | ||
1823 | static int ip_rt_bug(struct sk_buff *skb) | |
1824 | { | |
91df42be JP |
1825 | pr_debug("%s: %pI4 -> %pI4, %s\n", |
1826 | __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1827 | skb->dev ? skb->dev->name : "?"); | |
1da177e4 | 1828 | kfree_skb(skb); |
c378a9c0 | 1829 | WARN_ON(1); |
1da177e4 LT |
1830 | return 0; |
1831 | } | |
1832 | ||
1833 | /* | |
1834 | We do not cache source address of outgoing interface, | |
1835 | because it is used only by IP RR, TS and SRR options, | |
1836 | so that it out of fast path. | |
1837 | ||
1838 | BTW remember: "addr" is allowed to be not aligned | |
1839 | in IP options! | |
1840 | */ | |
1841 | ||
8e36360a | 1842 | void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) |
1da177e4 | 1843 | { |
a61ced5d | 1844 | __be32 src; |
1da177e4 | 1845 | |
c7537967 | 1846 | if (rt_is_output_route(rt)) |
c5be24ff | 1847 | src = ip_hdr(skb)->saddr; |
ebc0ffae | 1848 | else { |
8e36360a DM |
1849 | struct fib_result res; |
1850 | struct flowi4 fl4; | |
1851 | struct iphdr *iph; | |
1852 | ||
1853 | iph = ip_hdr(skb); | |
1854 | ||
1855 | memset(&fl4, 0, sizeof(fl4)); | |
1856 | fl4.daddr = iph->daddr; | |
1857 | fl4.saddr = iph->saddr; | |
b0fe4a31 | 1858 | fl4.flowi4_tos = RT_TOS(iph->tos); |
8e36360a DM |
1859 | fl4.flowi4_oif = rt->dst.dev->ifindex; |
1860 | fl4.flowi4_iif = skb->dev->ifindex; | |
1861 | fl4.flowi4_mark = skb->mark; | |
5e2b61f7 | 1862 | |
ebc0ffae | 1863 | rcu_read_lock(); |
68a5e3dd | 1864 | if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0) |
436c3b66 | 1865 | src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); |
ebc0ffae ED |
1866 | else |
1867 | src = inet_select_addr(rt->dst.dev, rt->rt_gateway, | |
1da177e4 | 1868 | RT_SCOPE_UNIVERSE); |
ebc0ffae ED |
1869 | rcu_read_unlock(); |
1870 | } | |
1da177e4 LT |
1871 | memcpy(addr, &src, 4); |
1872 | } | |
1873 | ||
c7066f70 | 1874 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1875 | static void set_class_tag(struct rtable *rt, u32 tag) |
1876 | { | |
d8d1f30b CG |
1877 | if (!(rt->dst.tclassid & 0xFFFF)) |
1878 | rt->dst.tclassid |= tag & 0xFFFF; | |
1879 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1880 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1da177e4 LT |
1881 | } |
1882 | #endif | |
1883 | ||
0dbaee3b DM |
1884 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst) |
1885 | { | |
1886 | unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS); | |
1887 | ||
1888 | if (advmss == 0) { | |
1889 | advmss = max_t(unsigned int, dst->dev->mtu - 40, | |
1890 | ip_rt_min_advmss); | |
1891 | if (advmss > 65535 - 40) | |
1892 | advmss = 65535 - 40; | |
1893 | } | |
1894 | return advmss; | |
1895 | } | |
1896 | ||
ebb762f2 | 1897 | static unsigned int ipv4_mtu(const struct dst_entry *dst) |
d33e4553 | 1898 | { |
261663b0 | 1899 | const struct rtable *rt = (const struct rtable *) dst; |
618f9bc7 SK |
1900 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
1901 | ||
261663b0 | 1902 | if (mtu && rt_is_output_route(rt)) |
618f9bc7 SK |
1903 | return mtu; |
1904 | ||
1905 | mtu = dst->dev->mtu; | |
d33e4553 DM |
1906 | |
1907 | if (unlikely(dst_metric_locked(dst, RTAX_MTU))) { | |
d33e4553 DM |
1908 | |
1909 | if (rt->rt_gateway != rt->rt_dst && mtu > 576) | |
1910 | mtu = 576; | |
1911 | } | |
1912 | ||
1913 | if (mtu > IP_MAX_MTU) | |
1914 | mtu = IP_MAX_MTU; | |
1915 | ||
1916 | return mtu; | |
1917 | } | |
1918 | ||
813b3b5d | 1919 | static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1920 | struct fib_info *fi) |
a4daad6b | 1921 | { |
54db0cc2 | 1922 | struct net *net = dev_net(rt->dst.dev); |
0131ba45 DM |
1923 | struct inet_peer *peer; |
1924 | int create = 0; | |
a4daad6b | 1925 | |
0131ba45 DM |
1926 | /* If a peer entry exists for this destination, we must hook |
1927 | * it up in order to get at cached metrics. | |
1928 | */ | |
813b3b5d | 1929 | if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS)) |
0131ba45 DM |
1930 | create = 1; |
1931 | ||
54db0cc2 | 1932 | rt->peer = peer = inet_getpeer_v4(net, rt->rt_dst, create); |
0131ba45 | 1933 | if (peer) { |
3c0afdca | 1934 | rt->rt_peer_genid = rt_peer_genid(); |
a4daad6b DM |
1935 | if (inet_metrics_new(peer)) |
1936 | memcpy(peer->metrics, fi->fib_metrics, | |
1937 | sizeof(u32) * RTAX_MAX); | |
1938 | dst_init_metrics(&rt->dst, peer->metrics, false); | |
2c8cec5c | 1939 | |
fe6fe792 | 1940 | check_peer_pmtu(&rt->dst, peer); |
ac3f48de | 1941 | |
f39925db DM |
1942 | if (peer->redirect_learned.a4 && |
1943 | peer->redirect_learned.a4 != rt->rt_gateway) { | |
1944 | rt->rt_gateway = peer->redirect_learned.a4; | |
1945 | rt->rt_flags |= RTCF_REDIRECTED; | |
1946 | } | |
0131ba45 DM |
1947 | } else { |
1948 | if (fi->fib_metrics != (u32 *) dst_default_metrics) { | |
1949 | rt->fi = fi; | |
1950 | atomic_inc(&fi->fib_clntref); | |
1951 | } | |
1952 | dst_init_metrics(&rt->dst, fi->fib_metrics, true); | |
a4daad6b DM |
1953 | } |
1954 | } | |
1955 | ||
813b3b5d | 1956 | static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1957 | const struct fib_result *res, |
982721f3 | 1958 | struct fib_info *fi, u16 type, u32 itag) |
1da177e4 | 1959 | { |
defb3519 | 1960 | struct dst_entry *dst = &rt->dst; |
1da177e4 LT |
1961 | |
1962 | if (fi) { | |
1963 | if (FIB_RES_GW(*res) && | |
1964 | FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
1965 | rt->rt_gateway = FIB_RES_GW(*res); | |
813b3b5d | 1966 | rt_init_metrics(rt, fl4, fi); |
c7066f70 | 1967 | #ifdef CONFIG_IP_ROUTE_CLASSID |
defb3519 | 1968 | dst->tclassid = FIB_RES_NH(*res).nh_tclassid; |
1da177e4 | 1969 | #endif |
d33e4553 | 1970 | } |
defb3519 | 1971 | |
defb3519 DM |
1972 | if (dst_mtu(dst) > IP_MAX_MTU) |
1973 | dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU); | |
0dbaee3b | 1974 | if (dst_metric_raw(dst, RTAX_ADVMSS) > 65535 - 40) |
defb3519 | 1975 | dst_metric_set(dst, RTAX_ADVMSS, 65535 - 40); |
1da177e4 | 1976 | |
c7066f70 | 1977 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1978 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
1979 | set_class_tag(rt, fib_rules_tclass(res)); | |
1980 | #endif | |
1981 | set_class_tag(rt, itag); | |
1982 | #endif | |
1da177e4 LT |
1983 | } |
1984 | ||
5c1e6aa3 DM |
1985 | static struct rtable *rt_dst_alloc(struct net_device *dev, |
1986 | bool nopolicy, bool noxfrm) | |
0c4dcd58 | 1987 | { |
5c1e6aa3 DM |
1988 | return dst_alloc(&ipv4_dst_ops, dev, 1, -1, |
1989 | DST_HOST | | |
1990 | (nopolicy ? DST_NOPOLICY : 0) | | |
1991 | (noxfrm ? DST_NOXFRM : 0)); | |
0c4dcd58 DM |
1992 | } |
1993 | ||
96d36220 | 1994 | /* called in rcu_read_lock() section */ |
9e12bb22 | 1995 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
1996 | u8 tos, struct net_device *dev, int our) |
1997 | { | |
96d36220 | 1998 | unsigned int hash; |
1da177e4 | 1999 | struct rtable *rth; |
a61ced5d | 2000 | __be32 spec_dst; |
96d36220 | 2001 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2002 | u32 itag = 0; |
b5f7e755 | 2003 | int err; |
1da177e4 LT |
2004 | |
2005 | /* Primary sanity checks. */ | |
2006 | ||
2007 | if (in_dev == NULL) | |
2008 | return -EINVAL; | |
2009 | ||
1e637c74 | 2010 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
f97c1e0c | 2011 | ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP)) |
1da177e4 LT |
2012 | goto e_inval; |
2013 | ||
f97c1e0c JP |
2014 | if (ipv4_is_zeronet(saddr)) { |
2015 | if (!ipv4_is_local_multicast(daddr)) | |
1da177e4 LT |
2016 | goto e_inval; |
2017 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
b5f7e755 | 2018 | } else { |
5c04c819 MS |
2019 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, &spec_dst, |
2020 | &itag); | |
b5f7e755 ED |
2021 | if (err < 0) |
2022 | goto e_err; | |
2023 | } | |
4e7b2f14 | 2024 | rth = rt_dst_alloc(dev_net(dev)->loopback_dev, |
5c1e6aa3 | 2025 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); |
1da177e4 LT |
2026 | if (!rth) |
2027 | goto e_nobufs; | |
2028 | ||
cf911662 DM |
2029 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2030 | rth->dst.tclassid = itag; | |
2031 | #endif | |
d8d1f30b | 2032 | rth->dst.output = ip_rt_bug; |
1da177e4 | 2033 | |
5e2b61f7 | 2034 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2035 | rth->rt_key_src = saddr; |
cf911662 DM |
2036 | rth->rt_genid = rt_genid(dev_net(dev)); |
2037 | rth->rt_flags = RTCF_MULTICAST; | |
2038 | rth->rt_type = RTN_MULTICAST; | |
475949d8 | 2039 | rth->rt_key_tos = tos; |
cf911662 | 2040 | rth->rt_dst = daddr; |
1da177e4 | 2041 | rth->rt_src = saddr; |
1b86a58f | 2042 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2043 | rth->rt_iif = dev->ifindex; |
5e2b61f7 | 2044 | rth->rt_oif = 0; |
cf911662 | 2045 | rth->rt_mark = skb->mark; |
1da177e4 LT |
2046 | rth->rt_gateway = daddr; |
2047 | rth->rt_spec_dst= spec_dst; | |
cf911662 DM |
2048 | rth->rt_peer_genid = 0; |
2049 | rth->peer = NULL; | |
2050 | rth->fi = NULL; | |
1da177e4 | 2051 | if (our) { |
d8d1f30b | 2052 | rth->dst.input= ip_local_deliver; |
1da177e4 LT |
2053 | rth->rt_flags |= RTCF_LOCAL; |
2054 | } | |
2055 | ||
2056 | #ifdef CONFIG_IP_MROUTE | |
f97c1e0c | 2057 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) |
d8d1f30b | 2058 | rth->dst.input = ip_mr_input; |
1da177e4 LT |
2059 | #endif |
2060 | RT_CACHE_STAT_INC(in_slow_mc); | |
2061 | ||
e84f84f2 | 2062 | hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev))); |
b23dd4fe | 2063 | rth = rt_intern_hash(hash, rth, skb, dev->ifindex); |
9aa3c94c | 2064 | return IS_ERR(rth) ? PTR_ERR(rth) : 0; |
1da177e4 LT |
2065 | |
2066 | e_nobufs: | |
1da177e4 | 2067 | return -ENOBUFS; |
1da177e4 | 2068 | e_inval: |
96d36220 | 2069 | return -EINVAL; |
b5f7e755 | 2070 | e_err: |
b5f7e755 | 2071 | return err; |
1da177e4 LT |
2072 | } |
2073 | ||
2074 | ||
2075 | static void ip_handle_martian_source(struct net_device *dev, | |
2076 | struct in_device *in_dev, | |
2077 | struct sk_buff *skb, | |
9e12bb22 AV |
2078 | __be32 daddr, |
2079 | __be32 saddr) | |
1da177e4 LT |
2080 | { |
2081 | RT_CACHE_STAT_INC(in_martian_src); | |
2082 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2083 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
2084 | /* | |
2085 | * RFC1812 recommendation, if source is martian, | |
2086 | * the only hint is MAC header. | |
2087 | */ | |
058bd4d2 | 2088 | pr_warn("martian source %pI4 from %pI4, on dev %s\n", |
673d57e7 | 2089 | &daddr, &saddr, dev->name); |
98e399f8 | 2090 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { |
058bd4d2 JP |
2091 | print_hex_dump(KERN_WARNING, "ll header: ", |
2092 | DUMP_PREFIX_OFFSET, 16, 1, | |
2093 | skb_mac_header(skb), | |
2094 | dev->hard_header_len, true); | |
1da177e4 LT |
2095 | } |
2096 | } | |
2097 | #endif | |
2098 | } | |
2099 | ||
47360228 | 2100 | /* called in rcu_read_lock() section */ |
5969f71d | 2101 | static int __mkroute_input(struct sk_buff *skb, |
982721f3 | 2102 | const struct fib_result *res, |
5969f71d SH |
2103 | struct in_device *in_dev, |
2104 | __be32 daddr, __be32 saddr, u32 tos, | |
2105 | struct rtable **result) | |
1da177e4 | 2106 | { |
1da177e4 LT |
2107 | struct rtable *rth; |
2108 | int err; | |
2109 | struct in_device *out_dev; | |
47360228 | 2110 | unsigned int flags = 0; |
d9c9df8c AV |
2111 | __be32 spec_dst; |
2112 | u32 itag; | |
1da177e4 LT |
2113 | |
2114 | /* get a working reference to the output device */ | |
47360228 | 2115 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); |
1da177e4 | 2116 | if (out_dev == NULL) { |
e87cc472 | 2117 | net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n"); |
1da177e4 LT |
2118 | return -EINVAL; |
2119 | } | |
2120 | ||
2121 | ||
5c04c819 MS |
2122 | err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), |
2123 | in_dev->dev, &spec_dst, &itag); | |
1da177e4 | 2124 | if (err < 0) { |
e905a9ed | 2125 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, |
1da177e4 | 2126 | saddr); |
e905a9ed | 2127 | |
1da177e4 LT |
2128 | goto cleanup; |
2129 | } | |
2130 | ||
2131 | if (err) | |
2132 | flags |= RTCF_DIRECTSRC; | |
2133 | ||
51b77cae | 2134 | if (out_dev == in_dev && err && |
1da177e4 LT |
2135 | (IN_DEV_SHARED_MEDIA(out_dev) || |
2136 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
2137 | flags |= RTCF_DOREDIRECT; | |
2138 | ||
2139 | if (skb->protocol != htons(ETH_P_IP)) { | |
2140 | /* Not IP (i.e. ARP). Do not create route, if it is | |
2141 | * invalid for proxy arp. DNAT routes are always valid. | |
65324144 JDB |
2142 | * |
2143 | * Proxy arp feature have been extended to allow, ARP | |
2144 | * replies back to the same interface, to support | |
2145 | * Private VLAN switch technologies. See arp.c. | |
1da177e4 | 2146 | */ |
65324144 JDB |
2147 | if (out_dev == in_dev && |
2148 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
1da177e4 LT |
2149 | err = -EINVAL; |
2150 | goto cleanup; | |
2151 | } | |
2152 | } | |
2153 | ||
5c1e6aa3 DM |
2154 | rth = rt_dst_alloc(out_dev->dev, |
2155 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2156 | IN_DEV_CONF_GET(out_dev, NOXFRM)); |
1da177e4 LT |
2157 | if (!rth) { |
2158 | err = -ENOBUFS; | |
2159 | goto cleanup; | |
2160 | } | |
2161 | ||
5e2b61f7 | 2162 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2163 | rth->rt_key_src = saddr; |
cf911662 DM |
2164 | rth->rt_genid = rt_genid(dev_net(rth->dst.dev)); |
2165 | rth->rt_flags = flags; | |
2166 | rth->rt_type = res->type; | |
475949d8 | 2167 | rth->rt_key_tos = tos; |
cf911662 | 2168 | rth->rt_dst = daddr; |
1da177e4 | 2169 | rth->rt_src = saddr; |
1b86a58f | 2170 | rth->rt_route_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2171 | rth->rt_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2172 | rth->rt_oif = 0; |
cf911662 DM |
2173 | rth->rt_mark = skb->mark; |
2174 | rth->rt_gateway = daddr; | |
1da177e4 | 2175 | rth->rt_spec_dst= spec_dst; |
cf911662 DM |
2176 | rth->rt_peer_genid = 0; |
2177 | rth->peer = NULL; | |
2178 | rth->fi = NULL; | |
1da177e4 | 2179 | |
d8d1f30b CG |
2180 | rth->dst.input = ip_forward; |
2181 | rth->dst.output = ip_output; | |
1da177e4 | 2182 | |
5e2b61f7 | 2183 | rt_set_nexthop(rth, NULL, res, res->fi, res->type, itag); |
1da177e4 | 2184 | |
1da177e4 LT |
2185 | *result = rth; |
2186 | err = 0; | |
2187 | cleanup: | |
1da177e4 | 2188 | return err; |
e905a9ed | 2189 | } |
1da177e4 | 2190 | |
5969f71d SH |
2191 | static int ip_mkroute_input(struct sk_buff *skb, |
2192 | struct fib_result *res, | |
68a5e3dd | 2193 | const struct flowi4 *fl4, |
5969f71d SH |
2194 | struct in_device *in_dev, |
2195 | __be32 daddr, __be32 saddr, u32 tos) | |
1da177e4 | 2196 | { |
5e73ea1a | 2197 | struct rtable *rth = NULL; |
1da177e4 | 2198 | int err; |
95c96174 | 2199 | unsigned int hash; |
1da177e4 LT |
2200 | |
2201 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
ff3fccb3 | 2202 | if (res->fi && res->fi->fib_nhs > 1) |
1b7fe593 | 2203 | fib_select_multipath(res); |
1da177e4 LT |
2204 | #endif |
2205 | ||
2206 | /* create a routing cache entry */ | |
2207 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth); | |
2208 | if (err) | |
2209 | return err; | |
1da177e4 LT |
2210 | |
2211 | /* put it into the cache */ | |
68a5e3dd | 2212 | hash = rt_hash(daddr, saddr, fl4->flowi4_iif, |
d8d1f30b | 2213 | rt_genid(dev_net(rth->dst.dev))); |
68a5e3dd | 2214 | rth = rt_intern_hash(hash, rth, skb, fl4->flowi4_iif); |
b23dd4fe DM |
2215 | if (IS_ERR(rth)) |
2216 | return PTR_ERR(rth); | |
2217 | return 0; | |
1da177e4 LT |
2218 | } |
2219 | ||
1da177e4 LT |
2220 | /* |
2221 | * NOTE. We drop all the packets that has local source | |
2222 | * addresses, because every properly looped back packet | |
2223 | * must have correct destination already attached by output routine. | |
2224 | * | |
2225 | * Such approach solves two big problems: | |
2226 | * 1. Not simplex devices are handled properly. | |
2227 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
ebc0ffae | 2228 | * called with rcu_read_lock() |
1da177e4 LT |
2229 | */ |
2230 | ||
9e12bb22 | 2231 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
2232 | u8 tos, struct net_device *dev) |
2233 | { | |
2234 | struct fib_result res; | |
96d36220 | 2235 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
68a5e3dd | 2236 | struct flowi4 fl4; |
95c96174 | 2237 | unsigned int flags = 0; |
1da177e4 | 2238 | u32 itag = 0; |
95c96174 ED |
2239 | struct rtable *rth; |
2240 | unsigned int hash; | |
9e12bb22 | 2241 | __be32 spec_dst; |
1da177e4 | 2242 | int err = -EINVAL; |
5e73ea1a | 2243 | struct net *net = dev_net(dev); |
1da177e4 LT |
2244 | |
2245 | /* IP on this device is disabled. */ | |
2246 | ||
2247 | if (!in_dev) | |
2248 | goto out; | |
2249 | ||
2250 | /* Check for the most weird martians, which can be not detected | |
2251 | by fib_lookup. | |
2252 | */ | |
2253 | ||
1e637c74 | 2254 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
f97c1e0c | 2255 | ipv4_is_loopback(saddr)) |
1da177e4 LT |
2256 | goto martian_source; |
2257 | ||
27a954bd | 2258 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) |
1da177e4 LT |
2259 | goto brd_input; |
2260 | ||
2261 | /* Accept zero addresses only to limited broadcast; | |
2262 | * I even do not know to fix it or not. Waiting for complains :-) | |
2263 | */ | |
f97c1e0c | 2264 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2265 | goto martian_source; |
2266 | ||
27a954bd | 2267 | if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr)) |
1da177e4 LT |
2268 | goto martian_destination; |
2269 | ||
2270 | /* | |
2271 | * Now we are ready to route packet. | |
2272 | */ | |
68a5e3dd DM |
2273 | fl4.flowi4_oif = 0; |
2274 | fl4.flowi4_iif = dev->ifindex; | |
2275 | fl4.flowi4_mark = skb->mark; | |
2276 | fl4.flowi4_tos = tos; | |
2277 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
2278 | fl4.daddr = daddr; | |
2279 | fl4.saddr = saddr; | |
2280 | err = fib_lookup(net, &fl4, &res); | |
ebc0ffae | 2281 | if (err != 0) { |
1da177e4 | 2282 | if (!IN_DEV_FORWARD(in_dev)) |
2c2910a4 | 2283 | goto e_hostunreach; |
1da177e4 LT |
2284 | goto no_route; |
2285 | } | |
1da177e4 LT |
2286 | |
2287 | RT_CACHE_STAT_INC(in_slow_tot); | |
2288 | ||
2289 | if (res.type == RTN_BROADCAST) | |
2290 | goto brd_input; | |
2291 | ||
2292 | if (res.type == RTN_LOCAL) { | |
5c04c819 | 2293 | err = fib_validate_source(skb, saddr, daddr, tos, |
ebc0ffae | 2294 | net->loopback_dev->ifindex, |
5c04c819 | 2295 | dev, &spec_dst, &itag); |
b5f7e755 ED |
2296 | if (err < 0) |
2297 | goto martian_source_keep_err; | |
2298 | if (err) | |
1da177e4 LT |
2299 | flags |= RTCF_DIRECTSRC; |
2300 | spec_dst = daddr; | |
2301 | goto local_input; | |
2302 | } | |
2303 | ||
2304 | if (!IN_DEV_FORWARD(in_dev)) | |
2c2910a4 | 2305 | goto e_hostunreach; |
1da177e4 LT |
2306 | if (res.type != RTN_UNICAST) |
2307 | goto martian_destination; | |
2308 | ||
68a5e3dd | 2309 | err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos); |
1da177e4 LT |
2310 | out: return err; |
2311 | ||
2312 | brd_input: | |
2313 | if (skb->protocol != htons(ETH_P_IP)) | |
2314 | goto e_inval; | |
2315 | ||
f97c1e0c | 2316 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2317 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); |
2318 | else { | |
5c04c819 MS |
2319 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, &spec_dst, |
2320 | &itag); | |
1da177e4 | 2321 | if (err < 0) |
b5f7e755 | 2322 | goto martian_source_keep_err; |
1da177e4 LT |
2323 | if (err) |
2324 | flags |= RTCF_DIRECTSRC; | |
2325 | } | |
2326 | flags |= RTCF_BROADCAST; | |
2327 | res.type = RTN_BROADCAST; | |
2328 | RT_CACHE_STAT_INC(in_brd); | |
2329 | ||
2330 | local_input: | |
5c1e6aa3 DM |
2331 | rth = rt_dst_alloc(net->loopback_dev, |
2332 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); | |
1da177e4 LT |
2333 | if (!rth) |
2334 | goto e_nobufs; | |
2335 | ||
cf911662 | 2336 | rth->dst.input= ip_local_deliver; |
d8d1f30b | 2337 | rth->dst.output= ip_rt_bug; |
cf911662 DM |
2338 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2339 | rth->dst.tclassid = itag; | |
2340 | #endif | |
1da177e4 | 2341 | |
5e2b61f7 | 2342 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2343 | rth->rt_key_src = saddr; |
cf911662 DM |
2344 | rth->rt_genid = rt_genid(net); |
2345 | rth->rt_flags = flags|RTCF_LOCAL; | |
2346 | rth->rt_type = res.type; | |
475949d8 | 2347 | rth->rt_key_tos = tos; |
cf911662 | 2348 | rth->rt_dst = daddr; |
1da177e4 | 2349 | rth->rt_src = saddr; |
c7066f70 | 2350 | #ifdef CONFIG_IP_ROUTE_CLASSID |
d8d1f30b | 2351 | rth->dst.tclassid = itag; |
1da177e4 | 2352 | #endif |
1b86a58f | 2353 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2354 | rth->rt_iif = dev->ifindex; |
cf911662 DM |
2355 | rth->rt_oif = 0; |
2356 | rth->rt_mark = skb->mark; | |
1da177e4 LT |
2357 | rth->rt_gateway = daddr; |
2358 | rth->rt_spec_dst= spec_dst; | |
cf911662 DM |
2359 | rth->rt_peer_genid = 0; |
2360 | rth->peer = NULL; | |
2361 | rth->fi = NULL; | |
1da177e4 | 2362 | if (res.type == RTN_UNREACHABLE) { |
d8d1f30b CG |
2363 | rth->dst.input= ip_error; |
2364 | rth->dst.error= -err; | |
1da177e4 LT |
2365 | rth->rt_flags &= ~RTCF_LOCAL; |
2366 | } | |
68a5e3dd DM |
2367 | hash = rt_hash(daddr, saddr, fl4.flowi4_iif, rt_genid(net)); |
2368 | rth = rt_intern_hash(hash, rth, skb, fl4.flowi4_iif); | |
b23dd4fe DM |
2369 | err = 0; |
2370 | if (IS_ERR(rth)) | |
2371 | err = PTR_ERR(rth); | |
ebc0ffae | 2372 | goto out; |
1da177e4 LT |
2373 | |
2374 | no_route: | |
2375 | RT_CACHE_STAT_INC(in_no_route); | |
2376 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
2377 | res.type = RTN_UNREACHABLE; | |
7f53878d MC |
2378 | if (err == -ESRCH) |
2379 | err = -ENETUNREACH; | |
1da177e4 LT |
2380 | goto local_input; |
2381 | ||
2382 | /* | |
2383 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2384 | */ | |
2385 | martian_destination: | |
2386 | RT_CACHE_STAT_INC(in_martian_dst); | |
2387 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
e87cc472 JP |
2388 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
2389 | net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n", | |
2390 | &daddr, &saddr, dev->name); | |
1da177e4 | 2391 | #endif |
2c2910a4 DE |
2392 | |
2393 | e_hostunreach: | |
e905a9ed | 2394 | err = -EHOSTUNREACH; |
ebc0ffae | 2395 | goto out; |
2c2910a4 | 2396 | |
1da177e4 LT |
2397 | e_inval: |
2398 | err = -EINVAL; | |
ebc0ffae | 2399 | goto out; |
1da177e4 LT |
2400 | |
2401 | e_nobufs: | |
2402 | err = -ENOBUFS; | |
ebc0ffae | 2403 | goto out; |
1da177e4 LT |
2404 | |
2405 | martian_source: | |
b5f7e755 ED |
2406 | err = -EINVAL; |
2407 | martian_source_keep_err: | |
1da177e4 | 2408 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); |
ebc0ffae | 2409 | goto out; |
1da177e4 LT |
2410 | } |
2411 | ||
407eadd9 ED |
2412 | int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
2413 | u8 tos, struct net_device *dev, bool noref) | |
1da177e4 | 2414 | { |
95c96174 ED |
2415 | struct rtable *rth; |
2416 | unsigned int hash; | |
1da177e4 | 2417 | int iif = dev->ifindex; |
b5921910 | 2418 | struct net *net; |
96d36220 | 2419 | int res; |
1da177e4 | 2420 | |
c346dca1 | 2421 | net = dev_net(dev); |
1080d709 | 2422 | |
96d36220 ED |
2423 | rcu_read_lock(); |
2424 | ||
1080d709 NH |
2425 | if (!rt_caching(net)) |
2426 | goto skip_cache; | |
2427 | ||
1da177e4 | 2428 | tos &= IPTOS_RT_MASK; |
e84f84f2 | 2429 | hash = rt_hash(daddr, saddr, iif, rt_genid(net)); |
1da177e4 | 2430 | |
1da177e4 | 2431 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2432 | rth = rcu_dereference(rth->dst.rt_next)) { |
5e2b61f7 DM |
2433 | if ((((__force u32)rth->rt_key_dst ^ (__force u32)daddr) | |
2434 | ((__force u32)rth->rt_key_src ^ (__force u32)saddr) | | |
97a80410 | 2435 | (rth->rt_route_iif ^ iif) | |
475949d8 | 2436 | (rth->rt_key_tos ^ tos)) == 0 && |
5e2b61f7 | 2437 | rth->rt_mark == skb->mark && |
d8d1f30b | 2438 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2439 | !rt_is_expired(rth)) { |
de398fb8 | 2440 | ipv4_validate_peer(rth); |
407eadd9 | 2441 | if (noref) { |
d8d1f30b CG |
2442 | dst_use_noref(&rth->dst, jiffies); |
2443 | skb_dst_set_noref(skb, &rth->dst); | |
407eadd9 | 2444 | } else { |
d8d1f30b CG |
2445 | dst_use(&rth->dst, jiffies); |
2446 | skb_dst_set(skb, &rth->dst); | |
407eadd9 | 2447 | } |
1da177e4 LT |
2448 | RT_CACHE_STAT_INC(in_hit); |
2449 | rcu_read_unlock(); | |
1da177e4 LT |
2450 | return 0; |
2451 | } | |
2452 | RT_CACHE_STAT_INC(in_hlist_search); | |
2453 | } | |
1da177e4 | 2454 | |
1080d709 | 2455 | skip_cache: |
1da177e4 LT |
2456 | /* Multicast recognition logic is moved from route cache to here. |
2457 | The problem was that too many Ethernet cards have broken/missing | |
2458 | hardware multicast filters :-( As result the host on multicasting | |
2459 | network acquires a lot of useless route cache entries, sort of | |
2460 | SDR messages from all the world. Now we try to get rid of them. | |
2461 | Really, provided software IP multicast filter is organized | |
2462 | reasonably (at least, hashed), it does not result in a slowdown | |
2463 | comparing with route cache reject entries. | |
2464 | Note, that multicast routers are not affected, because | |
2465 | route cache entry is created eventually. | |
2466 | */ | |
f97c1e0c | 2467 | if (ipv4_is_multicast(daddr)) { |
96d36220 | 2468 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2469 | |
96d36220 | 2470 | if (in_dev) { |
dbdd9a52 DM |
2471 | int our = ip_check_mc_rcu(in_dev, daddr, saddr, |
2472 | ip_hdr(skb)->protocol); | |
1da177e4 LT |
2473 | if (our |
2474 | #ifdef CONFIG_IP_MROUTE | |
9d4fb27d JP |
2475 | || |
2476 | (!ipv4_is_local_multicast(daddr) && | |
2477 | IN_DEV_MFORWARD(in_dev)) | |
1da177e4 | 2478 | #endif |
9d4fb27d | 2479 | ) { |
96d36220 ED |
2480 | int res = ip_route_input_mc(skb, daddr, saddr, |
2481 | tos, dev, our); | |
1da177e4 | 2482 | rcu_read_unlock(); |
96d36220 | 2483 | return res; |
1da177e4 LT |
2484 | } |
2485 | } | |
2486 | rcu_read_unlock(); | |
2487 | return -EINVAL; | |
2488 | } | |
96d36220 ED |
2489 | res = ip_route_input_slow(skb, daddr, saddr, tos, dev); |
2490 | rcu_read_unlock(); | |
2491 | return res; | |
1da177e4 | 2492 | } |
407eadd9 | 2493 | EXPORT_SYMBOL(ip_route_input_common); |
1da177e4 | 2494 | |
ebc0ffae | 2495 | /* called with rcu_read_lock() */ |
982721f3 | 2496 | static struct rtable *__mkroute_output(const struct fib_result *res, |
68a5e3dd | 2497 | const struct flowi4 *fl4, |
813b3b5d | 2498 | __be32 orig_daddr, __be32 orig_saddr, |
f61759e6 JA |
2499 | int orig_oif, __u8 orig_rtos, |
2500 | struct net_device *dev_out, | |
5ada5527 | 2501 | unsigned int flags) |
1da177e4 | 2502 | { |
982721f3 | 2503 | struct fib_info *fi = res->fi; |
5ada5527 | 2504 | struct in_device *in_dev; |
982721f3 | 2505 | u16 type = res->type; |
5ada5527 | 2506 | struct rtable *rth; |
1da177e4 | 2507 | |
68a5e3dd | 2508 | if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) |
5ada5527 | 2509 | return ERR_PTR(-EINVAL); |
1da177e4 | 2510 | |
68a5e3dd | 2511 | if (ipv4_is_lbcast(fl4->daddr)) |
982721f3 | 2512 | type = RTN_BROADCAST; |
68a5e3dd | 2513 | else if (ipv4_is_multicast(fl4->daddr)) |
982721f3 | 2514 | type = RTN_MULTICAST; |
68a5e3dd | 2515 | else if (ipv4_is_zeronet(fl4->daddr)) |
5ada5527 | 2516 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
2517 | |
2518 | if (dev_out->flags & IFF_LOOPBACK) | |
2519 | flags |= RTCF_LOCAL; | |
2520 | ||
dd28d1a0 | 2521 | in_dev = __in_dev_get_rcu(dev_out); |
ebc0ffae | 2522 | if (!in_dev) |
5ada5527 | 2523 | return ERR_PTR(-EINVAL); |
ebc0ffae | 2524 | |
982721f3 | 2525 | if (type == RTN_BROADCAST) { |
1da177e4 | 2526 | flags |= RTCF_BROADCAST | RTCF_LOCAL; |
982721f3 DM |
2527 | fi = NULL; |
2528 | } else if (type == RTN_MULTICAST) { | |
dd28d1a0 | 2529 | flags |= RTCF_MULTICAST | RTCF_LOCAL; |
813b3b5d DM |
2530 | if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, |
2531 | fl4->flowi4_proto)) | |
1da177e4 LT |
2532 | flags &= ~RTCF_LOCAL; |
2533 | /* If multicast route do not exist use | |
dd28d1a0 ED |
2534 | * default one, but do not gateway in this case. |
2535 | * Yes, it is hack. | |
1da177e4 | 2536 | */ |
982721f3 DM |
2537 | if (fi && res->prefixlen < 4) |
2538 | fi = NULL; | |
1da177e4 LT |
2539 | } |
2540 | ||
5c1e6aa3 DM |
2541 | rth = rt_dst_alloc(dev_out, |
2542 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2543 | IN_DEV_CONF_GET(in_dev, NOXFRM)); |
8391d07b | 2544 | if (!rth) |
5ada5527 | 2545 | return ERR_PTR(-ENOBUFS); |
8391d07b | 2546 | |
cf911662 DM |
2547 | rth->dst.output = ip_output; |
2548 | ||
813b3b5d DM |
2549 | rth->rt_key_dst = orig_daddr; |
2550 | rth->rt_key_src = orig_saddr; | |
cf911662 DM |
2551 | rth->rt_genid = rt_genid(dev_net(dev_out)); |
2552 | rth->rt_flags = flags; | |
2553 | rth->rt_type = type; | |
f61759e6 | 2554 | rth->rt_key_tos = orig_rtos; |
68a5e3dd DM |
2555 | rth->rt_dst = fl4->daddr; |
2556 | rth->rt_src = fl4->saddr; | |
1b86a58f | 2557 | rth->rt_route_iif = 0; |
813b3b5d DM |
2558 | rth->rt_iif = orig_oif ? : dev_out->ifindex; |
2559 | rth->rt_oif = orig_oif; | |
2560 | rth->rt_mark = fl4->flowi4_mark; | |
68a5e3dd DM |
2561 | rth->rt_gateway = fl4->daddr; |
2562 | rth->rt_spec_dst= fl4->saddr; | |
cf911662 DM |
2563 | rth->rt_peer_genid = 0; |
2564 | rth->peer = NULL; | |
2565 | rth->fi = NULL; | |
1da177e4 LT |
2566 | |
2567 | RT_CACHE_STAT_INC(out_slow_tot); | |
2568 | ||
2569 | if (flags & RTCF_LOCAL) { | |
d8d1f30b | 2570 | rth->dst.input = ip_local_deliver; |
68a5e3dd | 2571 | rth->rt_spec_dst = fl4->daddr; |
1da177e4 LT |
2572 | } |
2573 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { | |
68a5e3dd | 2574 | rth->rt_spec_dst = fl4->saddr; |
e905a9ed | 2575 | if (flags & RTCF_LOCAL && |
1da177e4 | 2576 | !(dev_out->flags & IFF_LOOPBACK)) { |
d8d1f30b | 2577 | rth->dst.output = ip_mc_output; |
1da177e4 LT |
2578 | RT_CACHE_STAT_INC(out_slow_mc); |
2579 | } | |
2580 | #ifdef CONFIG_IP_MROUTE | |
982721f3 | 2581 | if (type == RTN_MULTICAST) { |
1da177e4 | 2582 | if (IN_DEV_MFORWARD(in_dev) && |
813b3b5d | 2583 | !ipv4_is_local_multicast(fl4->daddr)) { |
d8d1f30b CG |
2584 | rth->dst.input = ip_mr_input; |
2585 | rth->dst.output = ip_mc_output; | |
1da177e4 LT |
2586 | } |
2587 | } | |
2588 | #endif | |
2589 | } | |
2590 | ||
813b3b5d | 2591 | rt_set_nexthop(rth, fl4, res, fi, type, 0); |
1da177e4 | 2592 | |
5ada5527 | 2593 | return rth; |
1da177e4 LT |
2594 | } |
2595 | ||
1da177e4 LT |
2596 | /* |
2597 | * Major route resolver routine. | |
0197aa38 | 2598 | * called with rcu_read_lock(); |
1da177e4 LT |
2599 | */ |
2600 | ||
813b3b5d | 2601 | static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4) |
1da177e4 | 2602 | { |
1da177e4 | 2603 | struct net_device *dev_out = NULL; |
f61759e6 | 2604 | __u8 tos = RT_FL_TOS(fl4); |
813b3b5d DM |
2605 | unsigned int flags = 0; |
2606 | struct fib_result res; | |
5ada5527 | 2607 | struct rtable *rth; |
813b3b5d DM |
2608 | __be32 orig_daddr; |
2609 | __be32 orig_saddr; | |
2610 | int orig_oif; | |
1da177e4 LT |
2611 | |
2612 | res.fi = NULL; | |
2613 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
2614 | res.r = NULL; | |
2615 | #endif | |
2616 | ||
813b3b5d DM |
2617 | orig_daddr = fl4->daddr; |
2618 | orig_saddr = fl4->saddr; | |
2619 | orig_oif = fl4->flowi4_oif; | |
2620 | ||
2621 | fl4->flowi4_iif = net->loopback_dev->ifindex; | |
2622 | fl4->flowi4_tos = tos & IPTOS_RT_MASK; | |
2623 | fl4->flowi4_scope = ((tos & RTO_ONLINK) ? | |
2624 | RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); | |
44713b67 | 2625 | |
010c2708 | 2626 | rcu_read_lock(); |
813b3b5d | 2627 | if (fl4->saddr) { |
b23dd4fe | 2628 | rth = ERR_PTR(-EINVAL); |
813b3b5d DM |
2629 | if (ipv4_is_multicast(fl4->saddr) || |
2630 | ipv4_is_lbcast(fl4->saddr) || | |
2631 | ipv4_is_zeronet(fl4->saddr)) | |
1da177e4 LT |
2632 | goto out; |
2633 | ||
1da177e4 LT |
2634 | /* I removed check for oif == dev_out->oif here. |
2635 | It was wrong for two reasons: | |
1ab35276 DL |
2636 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr |
2637 | is assigned to multiple interfaces. | |
1da177e4 LT |
2638 | 2. Moreover, we are allowed to send packets with saddr |
2639 | of another iface. --ANK | |
2640 | */ | |
2641 | ||
813b3b5d DM |
2642 | if (fl4->flowi4_oif == 0 && |
2643 | (ipv4_is_multicast(fl4->daddr) || | |
2644 | ipv4_is_lbcast(fl4->daddr))) { | |
a210d01a | 2645 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2646 | dev_out = __ip_dev_find(net, fl4->saddr, false); |
a210d01a JA |
2647 | if (dev_out == NULL) |
2648 | goto out; | |
2649 | ||
1da177e4 LT |
2650 | /* Special hack: user can direct multicasts |
2651 | and limited broadcast via necessary interface | |
2652 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2653 | This hack is not just for fun, it allows | |
2654 | vic,vat and friends to work. | |
2655 | They bind socket to loopback, set ttl to zero | |
2656 | and expect that it will work. | |
2657 | From the viewpoint of routing cache they are broken, | |
2658 | because we are not allowed to build multicast path | |
2659 | with loopback source addr (look, routing cache | |
2660 | cannot know, that ttl is zero, so that packet | |
2661 | will not leave this host and route is valid). | |
2662 | Luckily, this hack is good workaround. | |
2663 | */ | |
2664 | ||
813b3b5d | 2665 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2666 | goto make_route; |
2667 | } | |
a210d01a | 2668 | |
813b3b5d | 2669 | if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { |
a210d01a | 2670 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2671 | if (!__ip_dev_find(net, fl4->saddr, false)) |
a210d01a | 2672 | goto out; |
a210d01a | 2673 | } |
1da177e4 LT |
2674 | } |
2675 | ||
2676 | ||
813b3b5d DM |
2677 | if (fl4->flowi4_oif) { |
2678 | dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); | |
b23dd4fe | 2679 | rth = ERR_PTR(-ENODEV); |
1da177e4 LT |
2680 | if (dev_out == NULL) |
2681 | goto out; | |
e5ed6399 HX |
2682 | |
2683 | /* RACE: Check return value of inet_select_addr instead. */ | |
fc75fc83 | 2684 | if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { |
b23dd4fe | 2685 | rth = ERR_PTR(-ENETUNREACH); |
fc75fc83 ED |
2686 | goto out; |
2687 | } | |
813b3b5d DM |
2688 | if (ipv4_is_local_multicast(fl4->daddr) || |
2689 | ipv4_is_lbcast(fl4->daddr)) { | |
2690 | if (!fl4->saddr) | |
2691 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2692 | RT_SCOPE_LINK); | |
1da177e4 LT |
2693 | goto make_route; |
2694 | } | |
813b3b5d DM |
2695 | if (fl4->saddr) { |
2696 | if (ipv4_is_multicast(fl4->daddr)) | |
2697 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2698 | fl4->flowi4_scope); | |
2699 | else if (!fl4->daddr) | |
2700 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2701 | RT_SCOPE_HOST); | |
1da177e4 LT |
2702 | } |
2703 | } | |
2704 | ||
813b3b5d DM |
2705 | if (!fl4->daddr) { |
2706 | fl4->daddr = fl4->saddr; | |
2707 | if (!fl4->daddr) | |
2708 | fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); | |
b40afd0e | 2709 | dev_out = net->loopback_dev; |
813b3b5d | 2710 | fl4->flowi4_oif = net->loopback_dev->ifindex; |
1da177e4 LT |
2711 | res.type = RTN_LOCAL; |
2712 | flags |= RTCF_LOCAL; | |
2713 | goto make_route; | |
2714 | } | |
2715 | ||
813b3b5d | 2716 | if (fib_lookup(net, fl4, &res)) { |
1da177e4 | 2717 | res.fi = NULL; |
813b3b5d | 2718 | if (fl4->flowi4_oif) { |
1da177e4 LT |
2719 | /* Apparently, routing tables are wrong. Assume, |
2720 | that the destination is on link. | |
2721 | ||
2722 | WHY? DW. | |
2723 | Because we are allowed to send to iface | |
2724 | even if it has NO routes and NO assigned | |
2725 | addresses. When oif is specified, routing | |
2726 | tables are looked up with only one purpose: | |
2727 | to catch if destination is gatewayed, rather than | |
2728 | direct. Moreover, if MSG_DONTROUTE is set, | |
2729 | we send packet, ignoring both routing tables | |
2730 | and ifaddr state. --ANK | |
2731 | ||
2732 | ||
2733 | We could make it even if oif is unknown, | |
2734 | likely IPv6, but we do not. | |
2735 | */ | |
2736 | ||
813b3b5d DM |
2737 | if (fl4->saddr == 0) |
2738 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2739 | RT_SCOPE_LINK); | |
1da177e4 LT |
2740 | res.type = RTN_UNICAST; |
2741 | goto make_route; | |
2742 | } | |
b23dd4fe | 2743 | rth = ERR_PTR(-ENETUNREACH); |
1da177e4 LT |
2744 | goto out; |
2745 | } | |
1da177e4 LT |
2746 | |
2747 | if (res.type == RTN_LOCAL) { | |
813b3b5d | 2748 | if (!fl4->saddr) { |
9fc3bbb4 | 2749 | if (res.fi->fib_prefsrc) |
813b3b5d | 2750 | fl4->saddr = res.fi->fib_prefsrc; |
9fc3bbb4 | 2751 | else |
813b3b5d | 2752 | fl4->saddr = fl4->daddr; |
9fc3bbb4 | 2753 | } |
b40afd0e | 2754 | dev_out = net->loopback_dev; |
813b3b5d | 2755 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2756 | res.fi = NULL; |
2757 | flags |= RTCF_LOCAL; | |
2758 | goto make_route; | |
2759 | } | |
2760 | ||
2761 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
813b3b5d | 2762 | if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0) |
1b7fe593 | 2763 | fib_select_multipath(&res); |
1da177e4 LT |
2764 | else |
2765 | #endif | |
21d8c49e DM |
2766 | if (!res.prefixlen && |
2767 | res.table->tb_num_default > 1 && | |
813b3b5d | 2768 | res.type == RTN_UNICAST && !fl4->flowi4_oif) |
0c838ff1 | 2769 | fib_select_default(&res); |
1da177e4 | 2770 | |
813b3b5d DM |
2771 | if (!fl4->saddr) |
2772 | fl4->saddr = FIB_RES_PREFSRC(net, res); | |
1da177e4 | 2773 | |
1da177e4 | 2774 | dev_out = FIB_RES_DEV(res); |
813b3b5d | 2775 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2776 | |
2777 | ||
2778 | make_route: | |
813b3b5d | 2779 | rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif, |
f61759e6 | 2780 | tos, dev_out, flags); |
b23dd4fe | 2781 | if (!IS_ERR(rth)) { |
5ada5527 DM |
2782 | unsigned int hash; |
2783 | ||
813b3b5d | 2784 | hash = rt_hash(orig_daddr, orig_saddr, orig_oif, |
5ada5527 | 2785 | rt_genid(dev_net(dev_out))); |
813b3b5d | 2786 | rth = rt_intern_hash(hash, rth, NULL, orig_oif); |
5ada5527 | 2787 | } |
1da177e4 | 2788 | |
010c2708 DM |
2789 | out: |
2790 | rcu_read_unlock(); | |
b23dd4fe | 2791 | return rth; |
1da177e4 LT |
2792 | } |
2793 | ||
813b3b5d | 2794 | struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4) |
1da177e4 | 2795 | { |
1da177e4 | 2796 | struct rtable *rth; |
010c2708 | 2797 | unsigned int hash; |
1da177e4 | 2798 | |
1080d709 NH |
2799 | if (!rt_caching(net)) |
2800 | goto slow_output; | |
2801 | ||
9d6ec938 | 2802 | hash = rt_hash(flp4->daddr, flp4->saddr, flp4->flowi4_oif, rt_genid(net)); |
1da177e4 LT |
2803 | |
2804 | rcu_read_lock_bh(); | |
a898def2 | 2805 | for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2806 | rth = rcu_dereference_bh(rth->dst.rt_next)) { |
9d6ec938 DM |
2807 | if (rth->rt_key_dst == flp4->daddr && |
2808 | rth->rt_key_src == flp4->saddr && | |
c7537967 | 2809 | rt_is_output_route(rth) && |
9d6ec938 DM |
2810 | rth->rt_oif == flp4->flowi4_oif && |
2811 | rth->rt_mark == flp4->flowi4_mark && | |
475949d8 | 2812 | !((rth->rt_key_tos ^ flp4->flowi4_tos) & |
b5921910 | 2813 | (IPTOS_RT_MASK | RTO_ONLINK)) && |
d8d1f30b | 2814 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2815 | !rt_is_expired(rth)) { |
de398fb8 | 2816 | ipv4_validate_peer(rth); |
d8d1f30b | 2817 | dst_use(&rth->dst, jiffies); |
1da177e4 LT |
2818 | RT_CACHE_STAT_INC(out_hit); |
2819 | rcu_read_unlock_bh(); | |
56157872 DM |
2820 | if (!flp4->saddr) |
2821 | flp4->saddr = rth->rt_src; | |
2822 | if (!flp4->daddr) | |
2823 | flp4->daddr = rth->rt_dst; | |
b23dd4fe | 2824 | return rth; |
1da177e4 LT |
2825 | } |
2826 | RT_CACHE_STAT_INC(out_hlist_search); | |
2827 | } | |
2828 | rcu_read_unlock_bh(); | |
2829 | ||
1080d709 | 2830 | slow_output: |
9d6ec938 | 2831 | return ip_route_output_slow(net, flp4); |
1da177e4 | 2832 | } |
d8c97a94 ACM |
2833 | EXPORT_SYMBOL_GPL(__ip_route_output_key); |
2834 | ||
ae2688d5 JW |
2835 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) |
2836 | { | |
2837 | return NULL; | |
2838 | } | |
2839 | ||
ebb762f2 | 2840 | static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst) |
ec831ea7 | 2841 | { |
618f9bc7 SK |
2842 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
2843 | ||
2844 | return mtu ? : dst->dev->mtu; | |
ec831ea7 RD |
2845 | } |
2846 | ||
14e50e57 DM |
2847 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) |
2848 | { | |
2849 | } | |
2850 | ||
0972ddb2 HB |
2851 | static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, |
2852 | unsigned long old) | |
2853 | { | |
2854 | return NULL; | |
2855 | } | |
2856 | ||
14e50e57 DM |
2857 | static struct dst_ops ipv4_dst_blackhole_ops = { |
2858 | .family = AF_INET, | |
09640e63 | 2859 | .protocol = cpu_to_be16(ETH_P_IP), |
14e50e57 | 2860 | .destroy = ipv4_dst_destroy, |
ae2688d5 | 2861 | .check = ipv4_blackhole_dst_check, |
ebb762f2 | 2862 | .mtu = ipv4_blackhole_mtu, |
214f45c9 | 2863 | .default_advmss = ipv4_default_advmss, |
14e50e57 | 2864 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, |
0972ddb2 | 2865 | .cow_metrics = ipv4_rt_blackhole_cow_metrics, |
d3aaeb38 | 2866 | .neigh_lookup = ipv4_neigh_lookup, |
14e50e57 DM |
2867 | }; |
2868 | ||
2774c131 | 2869 | struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) |
14e50e57 | 2870 | { |
5c1e6aa3 | 2871 | struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, 0, 0); |
2774c131 | 2872 | struct rtable *ort = (struct rtable *) dst_orig; |
14e50e57 DM |
2873 | |
2874 | if (rt) { | |
d8d1f30b | 2875 | struct dst_entry *new = &rt->dst; |
14e50e57 | 2876 | |
14e50e57 | 2877 | new->__use = 1; |
352e512c HX |
2878 | new->input = dst_discard; |
2879 | new->output = dst_discard; | |
defb3519 | 2880 | dst_copy_metrics(new, &ort->dst); |
14e50e57 | 2881 | |
d8d1f30b | 2882 | new->dev = ort->dst.dev; |
14e50e57 DM |
2883 | if (new->dev) |
2884 | dev_hold(new->dev); | |
2885 | ||
5e2b61f7 DM |
2886 | rt->rt_key_dst = ort->rt_key_dst; |
2887 | rt->rt_key_src = ort->rt_key_src; | |
475949d8 | 2888 | rt->rt_key_tos = ort->rt_key_tos; |
1b86a58f | 2889 | rt->rt_route_iif = ort->rt_route_iif; |
5e2b61f7 DM |
2890 | rt->rt_iif = ort->rt_iif; |
2891 | rt->rt_oif = ort->rt_oif; | |
2892 | rt->rt_mark = ort->rt_mark; | |
14e50e57 | 2893 | |
e84f84f2 | 2894 | rt->rt_genid = rt_genid(net); |
14e50e57 DM |
2895 | rt->rt_flags = ort->rt_flags; |
2896 | rt->rt_type = ort->rt_type; | |
2897 | rt->rt_dst = ort->rt_dst; | |
2898 | rt->rt_src = ort->rt_src; | |
14e50e57 DM |
2899 | rt->rt_gateway = ort->rt_gateway; |
2900 | rt->rt_spec_dst = ort->rt_spec_dst; | |
2901 | rt->peer = ort->peer; | |
2902 | if (rt->peer) | |
2903 | atomic_inc(&rt->peer->refcnt); | |
62fa8a84 DM |
2904 | rt->fi = ort->fi; |
2905 | if (rt->fi) | |
2906 | atomic_inc(&rt->fi->fib_clntref); | |
14e50e57 DM |
2907 | |
2908 | dst_free(new); | |
2909 | } | |
2910 | ||
2774c131 DM |
2911 | dst_release(dst_orig); |
2912 | ||
2913 | return rt ? &rt->dst : ERR_PTR(-ENOMEM); | |
14e50e57 DM |
2914 | } |
2915 | ||
9d6ec938 | 2916 | struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, |
b23dd4fe | 2917 | struct sock *sk) |
1da177e4 | 2918 | { |
9d6ec938 | 2919 | struct rtable *rt = __ip_route_output_key(net, flp4); |
1da177e4 | 2920 | |
b23dd4fe DM |
2921 | if (IS_ERR(rt)) |
2922 | return rt; | |
1da177e4 | 2923 | |
56157872 | 2924 | if (flp4->flowi4_proto) |
9d6ec938 DM |
2925 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
2926 | flowi4_to_flowi(flp4), | |
2927 | sk, 0); | |
1da177e4 | 2928 | |
b23dd4fe | 2929 | return rt; |
1da177e4 | 2930 | } |
d8c97a94 ACM |
2931 | EXPORT_SYMBOL_GPL(ip_route_output_flow); |
2932 | ||
4feb88e5 BT |
2933 | static int rt_fill_info(struct net *net, |
2934 | struct sk_buff *skb, u32 pid, u32 seq, int event, | |
b6544c0b | 2935 | int nowait, unsigned int flags) |
1da177e4 | 2936 | { |
511c3f92 | 2937 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 2938 | struct rtmsg *r; |
be403ea1 | 2939 | struct nlmsghdr *nlh; |
2bc8ca40 | 2940 | unsigned long expires = 0; |
fe6fe792 | 2941 | const struct inet_peer *peer = rt->peer; |
e3703b3d | 2942 | u32 id = 0, ts = 0, tsage = 0, error; |
be403ea1 TG |
2943 | |
2944 | nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags); | |
2945 | if (nlh == NULL) | |
26932566 | 2946 | return -EMSGSIZE; |
be403ea1 TG |
2947 | |
2948 | r = nlmsg_data(nlh); | |
1da177e4 LT |
2949 | r->rtm_family = AF_INET; |
2950 | r->rtm_dst_len = 32; | |
2951 | r->rtm_src_len = 0; | |
475949d8 | 2952 | r->rtm_tos = rt->rt_key_tos; |
1da177e4 | 2953 | r->rtm_table = RT_TABLE_MAIN; |
f3756b79 DM |
2954 | if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN)) |
2955 | goto nla_put_failure; | |
1da177e4 LT |
2956 | r->rtm_type = rt->rt_type; |
2957 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2958 | r->rtm_protocol = RTPROT_UNSPEC; | |
2959 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2960 | if (rt->rt_flags & RTCF_NOTIFY) | |
2961 | r->rtm_flags |= RTM_F_NOTIFY; | |
be403ea1 | 2962 | |
f3756b79 DM |
2963 | if (nla_put_be32(skb, RTA_DST, rt->rt_dst)) |
2964 | goto nla_put_failure; | |
5e2b61f7 | 2965 | if (rt->rt_key_src) { |
1da177e4 | 2966 | r->rtm_src_len = 32; |
f3756b79 DM |
2967 | if (nla_put_be32(skb, RTA_SRC, rt->rt_key_src)) |
2968 | goto nla_put_failure; | |
1da177e4 | 2969 | } |
f3756b79 DM |
2970 | if (rt->dst.dev && |
2971 | nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) | |
2972 | goto nla_put_failure; | |
c7066f70 | 2973 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
2974 | if (rt->dst.tclassid && |
2975 | nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid)) | |
2976 | goto nla_put_failure; | |
1da177e4 | 2977 | #endif |
f3756b79 DM |
2978 | if (rt_is_input_route(rt)) { |
2979 | if (nla_put_be32(skb, RTA_PREFSRC, rt->rt_spec_dst)) | |
2980 | goto nla_put_failure; | |
2981 | } else if (rt->rt_src != rt->rt_key_src) { | |
2982 | if (nla_put_be32(skb, RTA_PREFSRC, rt->rt_src)) | |
2983 | goto nla_put_failure; | |
2984 | } | |
2985 | if (rt->rt_dst != rt->rt_gateway && | |
2986 | nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway)) | |
2987 | goto nla_put_failure; | |
be403ea1 | 2988 | |
defb3519 | 2989 | if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) |
be403ea1 TG |
2990 | goto nla_put_failure; |
2991 | ||
f3756b79 DM |
2992 | if (rt->rt_mark && |
2993 | nla_put_be32(skb, RTA_MARK, rt->rt_mark)) | |
2994 | goto nla_put_failure; | |
963bfeee | 2995 | |
d8d1f30b | 2996 | error = rt->dst.error; |
fe6fe792 | 2997 | if (peer) { |
317fe0e6 | 2998 | inet_peer_refcheck(rt->peer); |
fe6fe792 ED |
2999 | id = atomic_read(&peer->ip_id_count) & 0xffff; |
3000 | if (peer->tcp_ts_stamp) { | |
3001 | ts = peer->tcp_ts; | |
3002 | tsage = get_seconds() - peer->tcp_ts_stamp; | |
1da177e4 | 3003 | } |
fe6fe792 | 3004 | expires = ACCESS_ONCE(peer->pmtu_expires); |
2bc8ca40 SK |
3005 | if (expires) { |
3006 | if (time_before(jiffies, expires)) | |
3007 | expires -= jiffies; | |
3008 | else | |
3009 | expires = 0; | |
3010 | } | |
1da177e4 | 3011 | } |
be403ea1 | 3012 | |
c7537967 | 3013 | if (rt_is_input_route(rt)) { |
1da177e4 | 3014 | #ifdef CONFIG_IP_MROUTE |
e448515c | 3015 | __be32 dst = rt->rt_dst; |
1da177e4 | 3016 | |
f97c1e0c | 3017 | if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) && |
4feb88e5 | 3018 | IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { |
9a1b9496 DM |
3019 | int err = ipmr_get_route(net, skb, |
3020 | rt->rt_src, rt->rt_dst, | |
3021 | r, nowait); | |
1da177e4 LT |
3022 | if (err <= 0) { |
3023 | if (!nowait) { | |
3024 | if (err == 0) | |
3025 | return 0; | |
be403ea1 | 3026 | goto nla_put_failure; |
1da177e4 LT |
3027 | } else { |
3028 | if (err == -EMSGSIZE) | |
be403ea1 | 3029 | goto nla_put_failure; |
e3703b3d | 3030 | error = err; |
1da177e4 LT |
3031 | } |
3032 | } | |
3033 | } else | |
3034 | #endif | |
f3756b79 DM |
3035 | if (nla_put_u32(skb, RTA_IIF, rt->rt_iif)) |
3036 | goto nla_put_failure; | |
1da177e4 LT |
3037 | } |
3038 | ||
d8d1f30b | 3039 | if (rtnl_put_cacheinfo(skb, &rt->dst, id, ts, tsage, |
e3703b3d TG |
3040 | expires, error) < 0) |
3041 | goto nla_put_failure; | |
be403ea1 TG |
3042 | |
3043 | return nlmsg_end(skb, nlh); | |
1da177e4 | 3044 | |
be403ea1 | 3045 | nla_put_failure: |
26932566 PM |
3046 | nlmsg_cancel(skb, nlh); |
3047 | return -EMSGSIZE; | |
1da177e4 LT |
3048 | } |
3049 | ||
5e73ea1a | 3050 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg) |
1da177e4 | 3051 | { |
3b1e0a65 | 3052 | struct net *net = sock_net(in_skb->sk); |
d889ce3b TG |
3053 | struct rtmsg *rtm; |
3054 | struct nlattr *tb[RTA_MAX+1]; | |
1da177e4 | 3055 | struct rtable *rt = NULL; |
9e12bb22 AV |
3056 | __be32 dst = 0; |
3057 | __be32 src = 0; | |
3058 | u32 iif; | |
d889ce3b | 3059 | int err; |
963bfeee | 3060 | int mark; |
1da177e4 LT |
3061 | struct sk_buff *skb; |
3062 | ||
d889ce3b TG |
3063 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); |
3064 | if (err < 0) | |
3065 | goto errout; | |
3066 | ||
3067 | rtm = nlmsg_data(nlh); | |
3068 | ||
1da177e4 | 3069 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
d889ce3b TG |
3070 | if (skb == NULL) { |
3071 | err = -ENOBUFS; | |
3072 | goto errout; | |
3073 | } | |
1da177e4 LT |
3074 | |
3075 | /* Reserve room for dummy headers, this skb can pass | |
3076 | through good chunk of routing engine. | |
3077 | */ | |
459a98ed | 3078 | skb_reset_mac_header(skb); |
c1d2bbe1 | 3079 | skb_reset_network_header(skb); |
d2c962b8 SH |
3080 | |
3081 | /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ | |
eddc9ec5 | 3082 | ip_hdr(skb)->protocol = IPPROTO_ICMP; |
1da177e4 LT |
3083 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); |
3084 | ||
17fb2c64 AV |
3085 | src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0; |
3086 | dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; | |
d889ce3b | 3087 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; |
963bfeee | 3088 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; |
1da177e4 LT |
3089 | |
3090 | if (iif) { | |
d889ce3b TG |
3091 | struct net_device *dev; |
3092 | ||
1937504d | 3093 | dev = __dev_get_by_index(net, iif); |
d889ce3b TG |
3094 | if (dev == NULL) { |
3095 | err = -ENODEV; | |
3096 | goto errout_free; | |
3097 | } | |
3098 | ||
1da177e4 LT |
3099 | skb->protocol = htons(ETH_P_IP); |
3100 | skb->dev = dev; | |
963bfeee | 3101 | skb->mark = mark; |
1da177e4 LT |
3102 | local_bh_disable(); |
3103 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
3104 | local_bh_enable(); | |
d889ce3b | 3105 | |
511c3f92 | 3106 | rt = skb_rtable(skb); |
d8d1f30b CG |
3107 | if (err == 0 && rt->dst.error) |
3108 | err = -rt->dst.error; | |
1da177e4 | 3109 | } else { |
68a5e3dd DM |
3110 | struct flowi4 fl4 = { |
3111 | .daddr = dst, | |
3112 | .saddr = src, | |
3113 | .flowi4_tos = rtm->rtm_tos, | |
3114 | .flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0, | |
3115 | .flowi4_mark = mark, | |
d889ce3b | 3116 | }; |
9d6ec938 | 3117 | rt = ip_route_output_key(net, &fl4); |
b23dd4fe DM |
3118 | |
3119 | err = 0; | |
3120 | if (IS_ERR(rt)) | |
3121 | err = PTR_ERR(rt); | |
1da177e4 | 3122 | } |
d889ce3b | 3123 | |
1da177e4 | 3124 | if (err) |
d889ce3b | 3125 | goto errout_free; |
1da177e4 | 3126 | |
d8d1f30b | 3127 | skb_dst_set(skb, &rt->dst); |
1da177e4 LT |
3128 | if (rtm->rtm_flags & RTM_F_NOTIFY) |
3129 | rt->rt_flags |= RTCF_NOTIFY; | |
3130 | ||
4feb88e5 | 3131 | err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, |
1937504d | 3132 | RTM_NEWROUTE, 0, 0); |
d889ce3b TG |
3133 | if (err <= 0) |
3134 | goto errout_free; | |
1da177e4 | 3135 | |
1937504d | 3136 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); |
d889ce3b | 3137 | errout: |
2942e900 | 3138 | return err; |
1da177e4 | 3139 | |
d889ce3b | 3140 | errout_free: |
1da177e4 | 3141 | kfree_skb(skb); |
d889ce3b | 3142 | goto errout; |
1da177e4 LT |
3143 | } |
3144 | ||
3145 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
3146 | { | |
3147 | struct rtable *rt; | |
3148 | int h, s_h; | |
3149 | int idx, s_idx; | |
1937504d DL |
3150 | struct net *net; |
3151 | ||
3b1e0a65 | 3152 | net = sock_net(skb->sk); |
1da177e4 LT |
3153 | |
3154 | s_h = cb->args[0]; | |
d8c92830 ED |
3155 | if (s_h < 0) |
3156 | s_h = 0; | |
1da177e4 | 3157 | s_idx = idx = cb->args[1]; |
a6272665 ED |
3158 | for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) { |
3159 | if (!rt_hash_table[h].chain) | |
3160 | continue; | |
1da177e4 | 3161 | rcu_read_lock_bh(); |
a898def2 | 3162 | for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt; |
d8d1f30b CG |
3163 | rt = rcu_dereference_bh(rt->dst.rt_next), idx++) { |
3164 | if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx) | |
1da177e4 | 3165 | continue; |
e84f84f2 | 3166 | if (rt_is_expired(rt)) |
29e75252 | 3167 | continue; |
d8d1f30b | 3168 | skb_dst_set_noref(skb, &rt->dst); |
4feb88e5 | 3169 | if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid, |
e905a9ed | 3170 | cb->nlh->nlmsg_seq, RTM_NEWROUTE, |
b6544c0b | 3171 | 1, NLM_F_MULTI) <= 0) { |
adf30907 | 3172 | skb_dst_drop(skb); |
1da177e4 LT |
3173 | rcu_read_unlock_bh(); |
3174 | goto done; | |
3175 | } | |
adf30907 | 3176 | skb_dst_drop(skb); |
1da177e4 LT |
3177 | } |
3178 | rcu_read_unlock_bh(); | |
3179 | } | |
3180 | ||
3181 | done: | |
3182 | cb->args[0] = h; | |
3183 | cb->args[1] = idx; | |
3184 | return skb->len; | |
3185 | } | |
3186 | ||
3187 | void ip_rt_multicast_event(struct in_device *in_dev) | |
3188 | { | |
76e6ebfb | 3189 | rt_cache_flush(dev_net(in_dev->dev), 0); |
1da177e4 LT |
3190 | } |
3191 | ||
3192 | #ifdef CONFIG_SYSCTL | |
81c684d1 | 3193 | static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, |
8d65af78 | 3194 | void __user *buffer, |
1da177e4 LT |
3195 | size_t *lenp, loff_t *ppos) |
3196 | { | |
3197 | if (write) { | |
639e104f | 3198 | int flush_delay; |
81c684d1 | 3199 | ctl_table ctl; |
39a23e75 | 3200 | struct net *net; |
639e104f | 3201 | |
81c684d1 DL |
3202 | memcpy(&ctl, __ctl, sizeof(ctl)); |
3203 | ctl.data = &flush_delay; | |
8d65af78 | 3204 | proc_dointvec(&ctl, write, buffer, lenp, ppos); |
639e104f | 3205 | |
81c684d1 | 3206 | net = (struct net *)__ctl->extra1; |
39a23e75 | 3207 | rt_cache_flush(net, flush_delay); |
1da177e4 | 3208 | return 0; |
e905a9ed | 3209 | } |
1da177e4 LT |
3210 | |
3211 | return -EINVAL; | |
3212 | } | |
3213 | ||
eeb61f71 | 3214 | static ctl_table ipv4_route_table[] = { |
1da177e4 | 3215 | { |
1da177e4 LT |
3216 | .procname = "gc_thresh", |
3217 | .data = &ipv4_dst_ops.gc_thresh, | |
3218 | .maxlen = sizeof(int), | |
3219 | .mode = 0644, | |
6d9f239a | 3220 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3221 | }, |
3222 | { | |
1da177e4 LT |
3223 | .procname = "max_size", |
3224 | .data = &ip_rt_max_size, | |
3225 | .maxlen = sizeof(int), | |
3226 | .mode = 0644, | |
6d9f239a | 3227 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3228 | }, |
3229 | { | |
3230 | /* Deprecated. Use gc_min_interval_ms */ | |
e905a9ed | 3231 | |
1da177e4 LT |
3232 | .procname = "gc_min_interval", |
3233 | .data = &ip_rt_gc_min_interval, | |
3234 | .maxlen = sizeof(int), | |
3235 | .mode = 0644, | |
6d9f239a | 3236 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3237 | }, |
3238 | { | |
1da177e4 LT |
3239 | .procname = "gc_min_interval_ms", |
3240 | .data = &ip_rt_gc_min_interval, | |
3241 | .maxlen = sizeof(int), | |
3242 | .mode = 0644, | |
6d9f239a | 3243 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 LT |
3244 | }, |
3245 | { | |
1da177e4 LT |
3246 | .procname = "gc_timeout", |
3247 | .data = &ip_rt_gc_timeout, | |
3248 | .maxlen = sizeof(int), | |
3249 | .mode = 0644, | |
6d9f239a | 3250 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 | 3251 | }, |
9f28a2fc ED |
3252 | { |
3253 | .procname = "gc_interval", | |
3254 | .data = &ip_rt_gc_interval, | |
3255 | .maxlen = sizeof(int), | |
3256 | .mode = 0644, | |
3257 | .proc_handler = proc_dointvec_jiffies, | |
3258 | }, | |
1da177e4 | 3259 | { |
1da177e4 LT |
3260 | .procname = "redirect_load", |
3261 | .data = &ip_rt_redirect_load, | |
3262 | .maxlen = sizeof(int), | |
3263 | .mode = 0644, | |
6d9f239a | 3264 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3265 | }, |
3266 | { | |
1da177e4 LT |
3267 | .procname = "redirect_number", |
3268 | .data = &ip_rt_redirect_number, | |
3269 | .maxlen = sizeof(int), | |
3270 | .mode = 0644, | |
6d9f239a | 3271 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3272 | }, |
3273 | { | |
1da177e4 LT |
3274 | .procname = "redirect_silence", |
3275 | .data = &ip_rt_redirect_silence, | |
3276 | .maxlen = sizeof(int), | |
3277 | .mode = 0644, | |
6d9f239a | 3278 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3279 | }, |
3280 | { | |
1da177e4 LT |
3281 | .procname = "error_cost", |
3282 | .data = &ip_rt_error_cost, | |
3283 | .maxlen = sizeof(int), | |
3284 | .mode = 0644, | |
6d9f239a | 3285 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3286 | }, |
3287 | { | |
1da177e4 LT |
3288 | .procname = "error_burst", |
3289 | .data = &ip_rt_error_burst, | |
3290 | .maxlen = sizeof(int), | |
3291 | .mode = 0644, | |
6d9f239a | 3292 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3293 | }, |
3294 | { | |
1da177e4 LT |
3295 | .procname = "gc_elasticity", |
3296 | .data = &ip_rt_gc_elasticity, | |
3297 | .maxlen = sizeof(int), | |
3298 | .mode = 0644, | |
6d9f239a | 3299 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3300 | }, |
3301 | { | |
1da177e4 LT |
3302 | .procname = "mtu_expires", |
3303 | .data = &ip_rt_mtu_expires, | |
3304 | .maxlen = sizeof(int), | |
3305 | .mode = 0644, | |
6d9f239a | 3306 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3307 | }, |
3308 | { | |
1da177e4 LT |
3309 | .procname = "min_pmtu", |
3310 | .data = &ip_rt_min_pmtu, | |
3311 | .maxlen = sizeof(int), | |
3312 | .mode = 0644, | |
6d9f239a | 3313 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3314 | }, |
3315 | { | |
1da177e4 LT |
3316 | .procname = "min_adv_mss", |
3317 | .data = &ip_rt_min_advmss, | |
3318 | .maxlen = sizeof(int), | |
3319 | .mode = 0644, | |
6d9f239a | 3320 | .proc_handler = proc_dointvec, |
1da177e4 | 3321 | }, |
f8572d8f | 3322 | { } |
1da177e4 | 3323 | }; |
39a23e75 | 3324 | |
39a23e75 DL |
3325 | static struct ctl_table ipv4_route_flush_table[] = { |
3326 | { | |
39a23e75 DL |
3327 | .procname = "flush", |
3328 | .maxlen = sizeof(int), | |
3329 | .mode = 0200, | |
6d9f239a | 3330 | .proc_handler = ipv4_sysctl_rtcache_flush, |
39a23e75 | 3331 | }, |
f8572d8f | 3332 | { }, |
39a23e75 DL |
3333 | }; |
3334 | ||
3335 | static __net_init int sysctl_route_net_init(struct net *net) | |
3336 | { | |
3337 | struct ctl_table *tbl; | |
3338 | ||
3339 | tbl = ipv4_route_flush_table; | |
09ad9bc7 | 3340 | if (!net_eq(net, &init_net)) { |
39a23e75 DL |
3341 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); |
3342 | if (tbl == NULL) | |
3343 | goto err_dup; | |
3344 | } | |
3345 | tbl[0].extra1 = net; | |
3346 | ||
ec8f23ce | 3347 | net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl); |
39a23e75 DL |
3348 | if (net->ipv4.route_hdr == NULL) |
3349 | goto err_reg; | |
3350 | return 0; | |
3351 | ||
3352 | err_reg: | |
3353 | if (tbl != ipv4_route_flush_table) | |
3354 | kfree(tbl); | |
3355 | err_dup: | |
3356 | return -ENOMEM; | |
3357 | } | |
3358 | ||
3359 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
3360 | { | |
3361 | struct ctl_table *tbl; | |
3362 | ||
3363 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
3364 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
3365 | BUG_ON(tbl == ipv4_route_flush_table); | |
3366 | kfree(tbl); | |
3367 | } | |
3368 | ||
3369 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
3370 | .init = sysctl_route_net_init, | |
3371 | .exit = sysctl_route_net_exit, | |
3372 | }; | |
1da177e4 LT |
3373 | #endif |
3374 | ||
3ee94372 | 3375 | static __net_init int rt_genid_init(struct net *net) |
9f5e97e5 | 3376 | { |
3ee94372 NH |
3377 | get_random_bytes(&net->ipv4.rt_genid, |
3378 | sizeof(net->ipv4.rt_genid)); | |
436c3b66 DM |
3379 | get_random_bytes(&net->ipv4.dev_addr_genid, |
3380 | sizeof(net->ipv4.dev_addr_genid)); | |
9f5e97e5 DL |
3381 | return 0; |
3382 | } | |
3383 | ||
3ee94372 NH |
3384 | static __net_initdata struct pernet_operations rt_genid_ops = { |
3385 | .init = rt_genid_init, | |
9f5e97e5 DL |
3386 | }; |
3387 | ||
c3426b47 DM |
3388 | static int __net_init ipv4_inetpeer_init(struct net *net) |
3389 | { | |
3390 | struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL); | |
3391 | ||
3392 | if (!bp) | |
3393 | return -ENOMEM; | |
3394 | inet_peer_base_init(bp); | |
3395 | net->ipv4.peers = bp; | |
3396 | return 0; | |
3397 | } | |
3398 | ||
3399 | static void __net_exit ipv4_inetpeer_exit(struct net *net) | |
3400 | { | |
3401 | struct inet_peer_base *bp = net->ipv4.peers; | |
3402 | ||
3403 | net->ipv4.peers = NULL; | |
3404 | __inetpeer_invalidate_tree(bp); | |
3405 | kfree(bp); | |
3406 | } | |
3407 | ||
3408 | static __net_initdata struct pernet_operations ipv4_inetpeer_ops = { | |
3409 | .init = ipv4_inetpeer_init, | |
3410 | .exit = ipv4_inetpeer_exit, | |
3411 | }; | |
9f5e97e5 | 3412 | |
c7066f70 | 3413 | #ifdef CONFIG_IP_ROUTE_CLASSID |
7d720c3e | 3414 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; |
c7066f70 | 3415 | #endif /* CONFIG_IP_ROUTE_CLASSID */ |
1da177e4 LT |
3416 | |
3417 | static __initdata unsigned long rhash_entries; | |
3418 | static int __init set_rhash_entries(char *str) | |
3419 | { | |
413c27d8 EZ |
3420 | ssize_t ret; |
3421 | ||
1da177e4 LT |
3422 | if (!str) |
3423 | return 0; | |
413c27d8 EZ |
3424 | |
3425 | ret = kstrtoul(str, 0, &rhash_entries); | |
3426 | if (ret) | |
3427 | return 0; | |
3428 | ||
1da177e4 LT |
3429 | return 1; |
3430 | } | |
3431 | __setup("rhash_entries=", set_rhash_entries); | |
3432 | ||
3433 | int __init ip_rt_init(void) | |
3434 | { | |
424c4b70 | 3435 | int rc = 0; |
1da177e4 | 3436 | |
c7066f70 | 3437 | #ifdef CONFIG_IP_ROUTE_CLASSID |
0dcec8c2 | 3438 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); |
1da177e4 LT |
3439 | if (!ip_rt_acct) |
3440 | panic("IP: failed to allocate ip_rt_acct\n"); | |
1da177e4 LT |
3441 | #endif |
3442 | ||
e5d679f3 AD |
3443 | ipv4_dst_ops.kmem_cachep = |
3444 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
20c2df83 | 3445 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 3446 | |
14e50e57 DM |
3447 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; |
3448 | ||
fc66f95c ED |
3449 | if (dst_entries_init(&ipv4_dst_ops) < 0) |
3450 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
3451 | ||
3452 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
3453 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
3454 | ||
424c4b70 ED |
3455 | rt_hash_table = (struct rt_hash_bucket *) |
3456 | alloc_large_system_hash("IP route cache", | |
3457 | sizeof(struct rt_hash_bucket), | |
3458 | rhash_entries, | |
4481374c | 3459 | (totalram_pages >= 128 * 1024) ? |
18955cfc | 3460 | 15 : 17, |
8d1502de | 3461 | 0, |
424c4b70 ED |
3462 | &rt_hash_log, |
3463 | &rt_hash_mask, | |
31fe62b9 | 3464 | 0, |
c9503e0f | 3465 | rhash_entries ? 0 : 512 * 1024); |
22c047cc ED |
3466 | memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket)); |
3467 | rt_hash_lock_init(); | |
1da177e4 LT |
3468 | |
3469 | ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1); | |
3470 | ip_rt_max_size = (rt_hash_mask + 1) * 16; | |
3471 | ||
1da177e4 LT |
3472 | devinet_init(); |
3473 | ip_fib_init(); | |
3474 | ||
9f28a2fc ED |
3475 | INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func); |
3476 | expires_ljiffies = jiffies; | |
3477 | schedule_delayed_work(&expires_work, | |
3478 | net_random() % ip_rt_gc_interval + ip_rt_gc_interval); | |
3479 | ||
73b38711 | 3480 | if (ip_rt_proc_init()) |
058bd4d2 | 3481 | pr_err("Unable to create route proc files\n"); |
1da177e4 LT |
3482 | #ifdef CONFIG_XFRM |
3483 | xfrm_init(); | |
a33bc5c1 | 3484 | xfrm4_init(ip_rt_max_size); |
1da177e4 | 3485 | #endif |
c7ac8679 | 3486 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL); |
63f3444f | 3487 | |
39a23e75 DL |
3488 | #ifdef CONFIG_SYSCTL |
3489 | register_pernet_subsys(&sysctl_route_ops); | |
3490 | #endif | |
3ee94372 | 3491 | register_pernet_subsys(&rt_genid_ops); |
c3426b47 | 3492 | register_pernet_subsys(&ipv4_inetpeer_ops); |
1da177e4 LT |
3493 | return rc; |
3494 | } | |
3495 | ||
a1bc6eb4 | 3496 | #ifdef CONFIG_SYSCTL |
eeb61f71 AV |
3497 | /* |
3498 | * We really need to sanitize the damn ipv4 init order, then all | |
3499 | * this nonsense will go away. | |
3500 | */ | |
3501 | void __init ip_static_sysctl_init(void) | |
3502 | { | |
4e5ca785 | 3503 | register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table); |
eeb61f71 | 3504 | } |
a1bc6eb4 | 3505 | #endif |