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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 | ||
f894cbf8 DM |
191 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, |
192 | struct sk_buff *skb, | |
193 | const void *daddr); | |
d3aaeb38 | 194 | |
1da177e4 LT |
195 | static struct dst_ops ipv4_dst_ops = { |
196 | .family = AF_INET, | |
09640e63 | 197 | .protocol = cpu_to_be16(ETH_P_IP), |
1da177e4 LT |
198 | .gc = rt_garbage_collect, |
199 | .check = ipv4_dst_check, | |
0dbaee3b | 200 | .default_advmss = ipv4_default_advmss, |
ebb762f2 | 201 | .mtu = ipv4_mtu, |
62fa8a84 | 202 | .cow_metrics = ipv4_cow_metrics, |
1da177e4 LT |
203 | .destroy = ipv4_dst_destroy, |
204 | .ifdown = ipv4_dst_ifdown, | |
205 | .negative_advice = ipv4_negative_advice, | |
206 | .link_failure = ipv4_link_failure, | |
207 | .update_pmtu = ip_rt_update_pmtu, | |
1ac06e03 | 208 | .local_out = __ip_local_out, |
d3aaeb38 | 209 | .neigh_lookup = ipv4_neigh_lookup, |
1da177e4 LT |
210 | }; |
211 | ||
212 | #define ECN_OR_COST(class) TC_PRIO_##class | |
213 | ||
4839c52b | 214 | const __u8 ip_tos2prio[16] = { |
1da177e4 | 215 | TC_PRIO_BESTEFFORT, |
4a2b9c37 | 216 | ECN_OR_COST(BESTEFFORT), |
1da177e4 LT |
217 | TC_PRIO_BESTEFFORT, |
218 | ECN_OR_COST(BESTEFFORT), | |
219 | TC_PRIO_BULK, | |
220 | ECN_OR_COST(BULK), | |
221 | TC_PRIO_BULK, | |
222 | ECN_OR_COST(BULK), | |
223 | TC_PRIO_INTERACTIVE, | |
224 | ECN_OR_COST(INTERACTIVE), | |
225 | TC_PRIO_INTERACTIVE, | |
226 | ECN_OR_COST(INTERACTIVE), | |
227 | TC_PRIO_INTERACTIVE_BULK, | |
228 | ECN_OR_COST(INTERACTIVE_BULK), | |
229 | TC_PRIO_INTERACTIVE_BULK, | |
230 | ECN_OR_COST(INTERACTIVE_BULK) | |
231 | }; | |
d4a96865 | 232 | EXPORT_SYMBOL(ip_tos2prio); |
1da177e4 LT |
233 | |
234 | /* | |
235 | * Route cache. | |
236 | */ | |
237 | ||
238 | /* The locking scheme is rather straight forward: | |
239 | * | |
240 | * 1) Read-Copy Update protects the buckets of the central route hash. | |
241 | * 2) Only writers remove entries, and they hold the lock | |
242 | * as they look at rtable reference counts. | |
243 | * 3) Only readers acquire references to rtable entries, | |
244 | * they do so with atomic increments and with the | |
245 | * lock held. | |
246 | */ | |
247 | ||
248 | struct rt_hash_bucket { | |
1c31720a | 249 | struct rtable __rcu *chain; |
22c047cc | 250 | }; |
1080d709 | 251 | |
8a25d5de IM |
252 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ |
253 | defined(CONFIG_PROVE_LOCKING) | |
22c047cc ED |
254 | /* |
255 | * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks | |
256 | * The size of this table is a power of two and depends on the number of CPUS. | |
62051200 | 257 | * (on lockdep we have a quite big spinlock_t, so keep the size down there) |
22c047cc | 258 | */ |
62051200 IM |
259 | #ifdef CONFIG_LOCKDEP |
260 | # define RT_HASH_LOCK_SZ 256 | |
22c047cc | 261 | #else |
62051200 IM |
262 | # if NR_CPUS >= 32 |
263 | # define RT_HASH_LOCK_SZ 4096 | |
264 | # elif NR_CPUS >= 16 | |
265 | # define RT_HASH_LOCK_SZ 2048 | |
266 | # elif NR_CPUS >= 8 | |
267 | # define RT_HASH_LOCK_SZ 1024 | |
268 | # elif NR_CPUS >= 4 | |
269 | # define RT_HASH_LOCK_SZ 512 | |
270 | # else | |
271 | # define RT_HASH_LOCK_SZ 256 | |
272 | # endif | |
22c047cc ED |
273 | #endif |
274 | ||
275 | static spinlock_t *rt_hash_locks; | |
276 | # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)] | |
1ff1cc20 PE |
277 | |
278 | static __init void rt_hash_lock_init(void) | |
279 | { | |
280 | int i; | |
281 | ||
282 | rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ, | |
283 | GFP_KERNEL); | |
284 | if (!rt_hash_locks) | |
285 | panic("IP: failed to allocate rt_hash_locks\n"); | |
286 | ||
287 | for (i = 0; i < RT_HASH_LOCK_SZ; i++) | |
288 | spin_lock_init(&rt_hash_locks[i]); | |
289 | } | |
22c047cc ED |
290 | #else |
291 | # define rt_hash_lock_addr(slot) NULL | |
1ff1cc20 PE |
292 | |
293 | static inline void rt_hash_lock_init(void) | |
294 | { | |
295 | } | |
22c047cc | 296 | #endif |
1da177e4 | 297 | |
817bc4db | 298 | static struct rt_hash_bucket *rt_hash_table __read_mostly; |
95c96174 | 299 | static unsigned int rt_hash_mask __read_mostly; |
817bc4db | 300 | static unsigned int rt_hash_log __read_mostly; |
1da177e4 | 301 | |
2f970d83 | 302 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); |
27f39c73 | 303 | #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field) |
1da177e4 | 304 | |
b00180de | 305 | static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx, |
0eae88f3 | 306 | int genid) |
1da177e4 | 307 | { |
0eae88f3 | 308 | return jhash_3words((__force u32)daddr, (__force u32)saddr, |
b00180de | 309 | idx, genid) |
29e75252 | 310 | & rt_hash_mask; |
1da177e4 LT |
311 | } |
312 | ||
e84f84f2 DL |
313 | static inline int rt_genid(struct net *net) |
314 | { | |
315 | return atomic_read(&net->ipv4.rt_genid); | |
316 | } | |
317 | ||
1da177e4 LT |
318 | #ifdef CONFIG_PROC_FS |
319 | struct rt_cache_iter_state { | |
a75e936f | 320 | struct seq_net_private p; |
1da177e4 | 321 | int bucket; |
29e75252 | 322 | int genid; |
1da177e4 LT |
323 | }; |
324 | ||
1218854a | 325 | static struct rtable *rt_cache_get_first(struct seq_file *seq) |
1da177e4 | 326 | { |
1218854a | 327 | struct rt_cache_iter_state *st = seq->private; |
1da177e4 | 328 | struct rtable *r = NULL; |
1da177e4 LT |
329 | |
330 | for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) { | |
33d480ce | 331 | if (!rcu_access_pointer(rt_hash_table[st->bucket].chain)) |
a6272665 | 332 | continue; |
1da177e4 | 333 | rcu_read_lock_bh(); |
a898def2 | 334 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
29e75252 | 335 | while (r) { |
d8d1f30b | 336 | if (dev_net(r->dst.dev) == seq_file_net(seq) && |
a75e936f | 337 | r->rt_genid == st->genid) |
29e75252 | 338 | return r; |
d8d1f30b | 339 | r = rcu_dereference_bh(r->dst.rt_next); |
29e75252 | 340 | } |
1da177e4 LT |
341 | rcu_read_unlock_bh(); |
342 | } | |
29e75252 | 343 | return r; |
1da177e4 LT |
344 | } |
345 | ||
1218854a | 346 | static struct rtable *__rt_cache_get_next(struct seq_file *seq, |
642d6318 | 347 | struct rtable *r) |
1da177e4 | 348 | { |
1218854a | 349 | struct rt_cache_iter_state *st = seq->private; |
a6272665 | 350 | |
1c31720a | 351 | r = rcu_dereference_bh(r->dst.rt_next); |
1da177e4 LT |
352 | while (!r) { |
353 | rcu_read_unlock_bh(); | |
a6272665 ED |
354 | do { |
355 | if (--st->bucket < 0) | |
356 | return NULL; | |
33d480ce | 357 | } while (!rcu_access_pointer(rt_hash_table[st->bucket].chain)); |
1da177e4 | 358 | rcu_read_lock_bh(); |
1c31720a | 359 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); |
1da177e4 | 360 | } |
1c31720a | 361 | return r; |
1da177e4 LT |
362 | } |
363 | ||
1218854a | 364 | static struct rtable *rt_cache_get_next(struct seq_file *seq, |
642d6318 DL |
365 | struct rtable *r) |
366 | { | |
1218854a YH |
367 | struct rt_cache_iter_state *st = seq->private; |
368 | while ((r = __rt_cache_get_next(seq, r)) != NULL) { | |
d8d1f30b | 369 | if (dev_net(r->dst.dev) != seq_file_net(seq)) |
a75e936f | 370 | continue; |
642d6318 DL |
371 | if (r->rt_genid == st->genid) |
372 | break; | |
373 | } | |
374 | return r; | |
375 | } | |
376 | ||
1218854a | 377 | static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) |
1da177e4 | 378 | { |
1218854a | 379 | struct rtable *r = rt_cache_get_first(seq); |
1da177e4 LT |
380 | |
381 | if (r) | |
1218854a | 382 | while (pos && (r = rt_cache_get_next(seq, r))) |
1da177e4 LT |
383 | --pos; |
384 | return pos ? NULL : r; | |
385 | } | |
386 | ||
387 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) | |
388 | { | |
29e75252 | 389 | struct rt_cache_iter_state *st = seq->private; |
29e75252 | 390 | if (*pos) |
1218854a | 391 | return rt_cache_get_idx(seq, *pos - 1); |
e84f84f2 | 392 | st->genid = rt_genid(seq_file_net(seq)); |
29e75252 | 393 | return SEQ_START_TOKEN; |
1da177e4 LT |
394 | } |
395 | ||
396 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
397 | { | |
29e75252 | 398 | struct rtable *r; |
1da177e4 LT |
399 | |
400 | if (v == SEQ_START_TOKEN) | |
1218854a | 401 | r = rt_cache_get_first(seq); |
1da177e4 | 402 | else |
1218854a | 403 | r = rt_cache_get_next(seq, v); |
1da177e4 LT |
404 | ++*pos; |
405 | return r; | |
406 | } | |
407 | ||
408 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
409 | { | |
410 | if (v && v != SEQ_START_TOKEN) | |
411 | rcu_read_unlock_bh(); | |
412 | } | |
413 | ||
414 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
415 | { | |
416 | if (v == SEQ_START_TOKEN) | |
417 | seq_printf(seq, "%-127s\n", | |
418 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
419 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
420 | "HHUptod\tSpecDst"); | |
421 | else { | |
422 | struct rtable *r = v; | |
3c521f2b | 423 | int len; |
218fa90f | 424 | |
0eae88f3 | 425 | seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t" |
794785bf DM |
426 | "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n", |
427 | r->dst.dev ? r->dst.dev->name : "*", | |
428 | (__force u32)r->rt_dst, | |
429 | (__force u32)r->rt_gateway, | |
430 | r->rt_flags, atomic_read(&r->dst.__refcnt), | |
431 | r->dst.__use, 0, (__force u32)r->rt_src, | |
432 | dst_metric_advmss(&r->dst) + 40, | |
433 | dst_metric(&r->dst, RTAX_WINDOW), 0, | |
434 | r->rt_key_tos, | |
435 | -1, 0, 0, &len); | |
5e659e4c PE |
436 | |
437 | seq_printf(seq, "%*s\n", 127 - len, ""); | |
e905a9ed YH |
438 | } |
439 | return 0; | |
1da177e4 LT |
440 | } |
441 | ||
f690808e | 442 | static const struct seq_operations rt_cache_seq_ops = { |
1da177e4 LT |
443 | .start = rt_cache_seq_start, |
444 | .next = rt_cache_seq_next, | |
445 | .stop = rt_cache_seq_stop, | |
446 | .show = rt_cache_seq_show, | |
447 | }; | |
448 | ||
449 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
450 | { | |
a75e936f | 451 | return seq_open_net(inode, file, &rt_cache_seq_ops, |
cf7732e4 | 452 | sizeof(struct rt_cache_iter_state)); |
1da177e4 LT |
453 | } |
454 | ||
9a32144e | 455 | static const struct file_operations rt_cache_seq_fops = { |
1da177e4 LT |
456 | .owner = THIS_MODULE, |
457 | .open = rt_cache_seq_open, | |
458 | .read = seq_read, | |
459 | .llseek = seq_lseek, | |
a75e936f | 460 | .release = seq_release_net, |
1da177e4 LT |
461 | }; |
462 | ||
463 | ||
464 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
465 | { | |
466 | int cpu; | |
467 | ||
468 | if (*pos == 0) | |
469 | return SEQ_START_TOKEN; | |
470 | ||
0f23174a | 471 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
472 | if (!cpu_possible(cpu)) |
473 | continue; | |
474 | *pos = cpu+1; | |
2f970d83 | 475 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
476 | } |
477 | return NULL; | |
478 | } | |
479 | ||
480 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
481 | { | |
482 | int cpu; | |
483 | ||
0f23174a | 484 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
485 | if (!cpu_possible(cpu)) |
486 | continue; | |
487 | *pos = cpu+1; | |
2f970d83 | 488 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
489 | } |
490 | return NULL; | |
e905a9ed | 491 | |
1da177e4 LT |
492 | } |
493 | ||
494 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
495 | { | |
496 | ||
497 | } | |
498 | ||
499 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
500 | { | |
501 | struct rt_cache_stat *st = v; | |
502 | ||
503 | if (v == SEQ_START_TOKEN) { | |
5bec0039 | 504 | 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 |
505 | return 0; |
506 | } | |
e905a9ed | 507 | |
1da177e4 LT |
508 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " |
509 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
fc66f95c | 510 | dst_entries_get_slow(&ipv4_dst_ops), |
1da177e4 LT |
511 | st->in_hit, |
512 | st->in_slow_tot, | |
513 | st->in_slow_mc, | |
514 | st->in_no_route, | |
515 | st->in_brd, | |
516 | st->in_martian_dst, | |
517 | st->in_martian_src, | |
518 | ||
519 | st->out_hit, | |
520 | st->out_slow_tot, | |
e905a9ed | 521 | st->out_slow_mc, |
1da177e4 LT |
522 | |
523 | st->gc_total, | |
524 | st->gc_ignored, | |
525 | st->gc_goal_miss, | |
526 | st->gc_dst_overflow, | |
527 | st->in_hlist_search, | |
528 | st->out_hlist_search | |
529 | ); | |
530 | return 0; | |
531 | } | |
532 | ||
f690808e | 533 | static const struct seq_operations rt_cpu_seq_ops = { |
1da177e4 LT |
534 | .start = rt_cpu_seq_start, |
535 | .next = rt_cpu_seq_next, | |
536 | .stop = rt_cpu_seq_stop, | |
537 | .show = rt_cpu_seq_show, | |
538 | }; | |
539 | ||
540 | ||
541 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
542 | { | |
543 | return seq_open(file, &rt_cpu_seq_ops); | |
544 | } | |
545 | ||
9a32144e | 546 | static const struct file_operations rt_cpu_seq_fops = { |
1da177e4 LT |
547 | .owner = THIS_MODULE, |
548 | .open = rt_cpu_seq_open, | |
549 | .read = seq_read, | |
550 | .llseek = seq_lseek, | |
551 | .release = seq_release, | |
552 | }; | |
553 | ||
c7066f70 | 554 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 555 | static int rt_acct_proc_show(struct seq_file *m, void *v) |
78c686e9 | 556 | { |
a661c419 AD |
557 | struct ip_rt_acct *dst, *src; |
558 | unsigned int i, j; | |
559 | ||
560 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
561 | if (!dst) | |
562 | return -ENOMEM; | |
563 | ||
564 | for_each_possible_cpu(i) { | |
565 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
566 | for (j = 0; j < 256; j++) { | |
567 | dst[j].o_bytes += src[j].o_bytes; | |
568 | dst[j].o_packets += src[j].o_packets; | |
569 | dst[j].i_bytes += src[j].i_bytes; | |
570 | dst[j].i_packets += src[j].i_packets; | |
571 | } | |
78c686e9 PE |
572 | } |
573 | ||
a661c419 AD |
574 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); |
575 | kfree(dst); | |
576 | return 0; | |
577 | } | |
78c686e9 | 578 | |
a661c419 AD |
579 | static int rt_acct_proc_open(struct inode *inode, struct file *file) |
580 | { | |
581 | return single_open(file, rt_acct_proc_show, NULL); | |
78c686e9 | 582 | } |
a661c419 AD |
583 | |
584 | static const struct file_operations rt_acct_proc_fops = { | |
585 | .owner = THIS_MODULE, | |
586 | .open = rt_acct_proc_open, | |
587 | .read = seq_read, | |
588 | .llseek = seq_lseek, | |
589 | .release = single_release, | |
590 | }; | |
78c686e9 | 591 | #endif |
107f1634 | 592 | |
73b38711 | 593 | static int __net_init ip_rt_do_proc_init(struct net *net) |
107f1634 PE |
594 | { |
595 | struct proc_dir_entry *pde; | |
596 | ||
597 | pde = proc_net_fops_create(net, "rt_cache", S_IRUGO, | |
598 | &rt_cache_seq_fops); | |
599 | if (!pde) | |
600 | goto err1; | |
601 | ||
77020720 WC |
602 | pde = proc_create("rt_cache", S_IRUGO, |
603 | net->proc_net_stat, &rt_cpu_seq_fops); | |
107f1634 PE |
604 | if (!pde) |
605 | goto err2; | |
606 | ||
c7066f70 | 607 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 608 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); |
107f1634 PE |
609 | if (!pde) |
610 | goto err3; | |
611 | #endif | |
612 | return 0; | |
613 | ||
c7066f70 | 614 | #ifdef CONFIG_IP_ROUTE_CLASSID |
107f1634 PE |
615 | err3: |
616 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
617 | #endif | |
618 | err2: | |
619 | remove_proc_entry("rt_cache", net->proc_net); | |
620 | err1: | |
621 | return -ENOMEM; | |
622 | } | |
73b38711 DL |
623 | |
624 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
625 | { | |
626 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
627 | remove_proc_entry("rt_cache", net->proc_net); | |
c7066f70 | 628 | #ifdef CONFIG_IP_ROUTE_CLASSID |
73b38711 | 629 | remove_proc_entry("rt_acct", net->proc_net); |
0a931acf | 630 | #endif |
73b38711 DL |
631 | } |
632 | ||
633 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
634 | .init = ip_rt_do_proc_init, | |
635 | .exit = ip_rt_do_proc_exit, | |
636 | }; | |
637 | ||
638 | static int __init ip_rt_proc_init(void) | |
639 | { | |
640 | return register_pernet_subsys(&ip_rt_proc_ops); | |
641 | } | |
642 | ||
107f1634 | 643 | #else |
73b38711 | 644 | static inline int ip_rt_proc_init(void) |
107f1634 PE |
645 | { |
646 | return 0; | |
647 | } | |
1da177e4 | 648 | #endif /* CONFIG_PROC_FS */ |
e905a9ed | 649 | |
5969f71d | 650 | static inline void rt_free(struct rtable *rt) |
1da177e4 | 651 | { |
d8d1f30b | 652 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
653 | } |
654 | ||
5969f71d | 655 | static inline void rt_drop(struct rtable *rt) |
1da177e4 | 656 | { |
1da177e4 | 657 | ip_rt_put(rt); |
d8d1f30b | 658 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); |
1da177e4 LT |
659 | } |
660 | ||
5969f71d | 661 | static inline int rt_fast_clean(struct rtable *rth) |
1da177e4 LT |
662 | { |
663 | /* Kill broadcast/multicast entries very aggresively, if they | |
664 | collide in hash table with more useful entries */ | |
665 | return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) && | |
c7537967 | 666 | rt_is_input_route(rth) && rth->dst.rt_next; |
1da177e4 LT |
667 | } |
668 | ||
5969f71d | 669 | static inline int rt_valuable(struct rtable *rth) |
1da177e4 LT |
670 | { |
671 | return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || | |
97bab73f | 672 | (rt_has_peer(rth) && rt_peer_ptr(rth)->pmtu_expires); |
1da177e4 LT |
673 | } |
674 | ||
675 | static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) | |
676 | { | |
677 | unsigned long age; | |
678 | int ret = 0; | |
679 | ||
d8d1f30b | 680 | if (atomic_read(&rth->dst.__refcnt)) |
1da177e4 LT |
681 | goto out; |
682 | ||
d8d1f30b | 683 | age = jiffies - rth->dst.lastuse; |
1da177e4 LT |
684 | if ((age <= tmo1 && !rt_fast_clean(rth)) || |
685 | (age <= tmo2 && rt_valuable(rth))) | |
686 | goto out; | |
687 | ret = 1; | |
688 | out: return ret; | |
689 | } | |
690 | ||
691 | /* Bits of score are: | |
692 | * 31: very valuable | |
693 | * 30: not quite useless | |
694 | * 29..0: usage counter | |
695 | */ | |
696 | static inline u32 rt_score(struct rtable *rt) | |
697 | { | |
d8d1f30b | 698 | u32 score = jiffies - rt->dst.lastuse; |
1da177e4 LT |
699 | |
700 | score = ~score & ~(3<<30); | |
701 | ||
702 | if (rt_valuable(rt)) | |
703 | score |= (1<<31); | |
704 | ||
c7537967 | 705 | if (rt_is_output_route(rt) || |
1da177e4 LT |
706 | !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL))) |
707 | score |= (1<<30); | |
708 | ||
709 | return score; | |
710 | } | |
711 | ||
1080d709 NH |
712 | static inline bool rt_caching(const struct net *net) |
713 | { | |
714 | return net->ipv4.current_rt_cache_rebuild_count <= | |
715 | net->ipv4.sysctl_rt_cache_rebuild_count; | |
716 | } | |
717 | ||
5e2b61f7 DM |
718 | static inline bool compare_hash_inputs(const struct rtable *rt1, |
719 | const struct rtable *rt2) | |
1080d709 | 720 | { |
5e2b61f7 DM |
721 | return ((((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
722 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
97a80410 | 723 | (rt1->rt_route_iif ^ rt2->rt_route_iif)) == 0); |
1080d709 NH |
724 | } |
725 | ||
5e2b61f7 | 726 | static inline int compare_keys(struct rtable *rt1, struct rtable *rt2) |
1da177e4 | 727 | { |
5e2b61f7 DM |
728 | return (((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) | |
729 | ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) | | |
730 | (rt1->rt_mark ^ rt2->rt_mark) | | |
475949d8 | 731 | (rt1->rt_key_tos ^ rt2->rt_key_tos) | |
d547f727 | 732 | (rt1->rt_route_iif ^ rt2->rt_route_iif) | |
97a80410 | 733 | (rt1->rt_oif ^ rt2->rt_oif)) == 0; |
1da177e4 LT |
734 | } |
735 | ||
b5921910 DL |
736 | static inline int compare_netns(struct rtable *rt1, struct rtable *rt2) |
737 | { | |
d8d1f30b | 738 | return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev)); |
b5921910 DL |
739 | } |
740 | ||
e84f84f2 DL |
741 | static inline int rt_is_expired(struct rtable *rth) |
742 | { | |
d8d1f30b | 743 | return rth->rt_genid != rt_genid(dev_net(rth->dst.dev)); |
e84f84f2 DL |
744 | } |
745 | ||
beb659bd ED |
746 | /* |
747 | * Perform a full scan of hash table and free all entries. | |
748 | * Can be called by a softirq or a process. | |
749 | * In the later case, we want to be reschedule if necessary | |
750 | */ | |
6561a3b1 | 751 | static void rt_do_flush(struct net *net, int process_context) |
beb659bd ED |
752 | { |
753 | unsigned int i; | |
754 | struct rtable *rth, *next; | |
755 | ||
756 | for (i = 0; i <= rt_hash_mask; i++) { | |
6561a3b1 DM |
757 | struct rtable __rcu **pprev; |
758 | struct rtable *list; | |
759 | ||
beb659bd ED |
760 | if (process_context && need_resched()) |
761 | cond_resched(); | |
33d480ce | 762 | rth = rcu_access_pointer(rt_hash_table[i].chain); |
beb659bd ED |
763 | if (!rth) |
764 | continue; | |
765 | ||
766 | spin_lock_bh(rt_hash_lock_addr(i)); | |
32cb5b4e | 767 | |
6561a3b1 DM |
768 | list = NULL; |
769 | pprev = &rt_hash_table[i].chain; | |
770 | rth = rcu_dereference_protected(*pprev, | |
1c31720a | 771 | lockdep_is_held(rt_hash_lock_addr(i))); |
32cb5b4e | 772 | |
6561a3b1 DM |
773 | while (rth) { |
774 | next = rcu_dereference_protected(rth->dst.rt_next, | |
1c31720a | 775 | lockdep_is_held(rt_hash_lock_addr(i))); |
6561a3b1 DM |
776 | |
777 | if (!net || | |
778 | net_eq(dev_net(rth->dst.dev), net)) { | |
779 | rcu_assign_pointer(*pprev, next); | |
780 | rcu_assign_pointer(rth->dst.rt_next, list); | |
781 | list = rth; | |
32cb5b4e | 782 | } else { |
6561a3b1 | 783 | pprev = &rth->dst.rt_next; |
32cb5b4e | 784 | } |
6561a3b1 | 785 | rth = next; |
32cb5b4e | 786 | } |
6561a3b1 | 787 | |
beb659bd ED |
788 | spin_unlock_bh(rt_hash_lock_addr(i)); |
789 | ||
6561a3b1 DM |
790 | for (; list; list = next) { |
791 | next = rcu_dereference_protected(list->dst.rt_next, 1); | |
792 | rt_free(list); | |
beb659bd ED |
793 | } |
794 | } | |
795 | } | |
796 | ||
1080d709 NH |
797 | /* |
798 | * While freeing expired entries, we compute average chain length | |
799 | * and standard deviation, using fixed-point arithmetic. | |
800 | * This to have an estimation of rt_chain_length_max | |
801 | * rt_chain_length_max = max(elasticity, AVG + 4*SD) | |
802 | * We use 3 bits for frational part, and 29 (or 61) for magnitude. | |
803 | */ | |
804 | ||
805 | #define FRACT_BITS 3 | |
806 | #define ONE (1UL << FRACT_BITS) | |
807 | ||
98376387 ED |
808 | /* |
809 | * Given a hash chain and an item in this hash chain, | |
810 | * find if a previous entry has the same hash_inputs | |
811 | * (but differs on tos, mark or oif) | |
812 | * Returns 0 if an alias is found. | |
813 | * Returns ONE if rth has no alias before itself. | |
814 | */ | |
815 | static int has_noalias(const struct rtable *head, const struct rtable *rth) | |
816 | { | |
817 | const struct rtable *aux = head; | |
818 | ||
819 | while (aux != rth) { | |
5e2b61f7 | 820 | if (compare_hash_inputs(aux, rth)) |
98376387 | 821 | return 0; |
1c31720a | 822 | aux = rcu_dereference_protected(aux->dst.rt_next, 1); |
98376387 ED |
823 | } |
824 | return ONE; | |
825 | } | |
826 | ||
9f28a2fc ED |
827 | static void rt_check_expire(void) |
828 | { | |
829 | static unsigned int rover; | |
830 | unsigned int i = rover, goal; | |
831 | struct rtable *rth; | |
832 | struct rtable __rcu **rthp; | |
833 | unsigned long samples = 0; | |
834 | unsigned long sum = 0, sum2 = 0; | |
835 | unsigned long delta; | |
836 | u64 mult; | |
837 | ||
838 | delta = jiffies - expires_ljiffies; | |
839 | expires_ljiffies = jiffies; | |
840 | mult = ((u64)delta) << rt_hash_log; | |
841 | if (ip_rt_gc_timeout > 1) | |
842 | do_div(mult, ip_rt_gc_timeout); | |
843 | goal = (unsigned int)mult; | |
844 | if (goal > rt_hash_mask) | |
845 | goal = rt_hash_mask + 1; | |
846 | for (; goal > 0; goal--) { | |
847 | unsigned long tmo = ip_rt_gc_timeout; | |
848 | unsigned long length; | |
849 | ||
850 | i = (i + 1) & rt_hash_mask; | |
851 | rthp = &rt_hash_table[i].chain; | |
852 | ||
853 | if (need_resched()) | |
854 | cond_resched(); | |
855 | ||
856 | samples++; | |
857 | ||
858 | if (rcu_dereference_raw(*rthp) == NULL) | |
859 | continue; | |
860 | length = 0; | |
861 | spin_lock_bh(rt_hash_lock_addr(i)); | |
862 | while ((rth = rcu_dereference_protected(*rthp, | |
863 | lockdep_is_held(rt_hash_lock_addr(i)))) != NULL) { | |
864 | prefetch(rth->dst.rt_next); | |
df67e6c9 DM |
865 | if (rt_is_expired(rth) || |
866 | rt_may_expire(rth, tmo, ip_rt_gc_timeout)) { | |
9f28a2fc ED |
867 | *rthp = rth->dst.rt_next; |
868 | rt_free(rth); | |
869 | continue; | |
870 | } | |
df67e6c9 DM |
871 | |
872 | /* We only count entries on a chain with equal | |
873 | * hash inputs once so that entries for | |
874 | * different QOS levels, and other non-hash | |
875 | * input attributes don't unfairly skew the | |
876 | * length computation | |
877 | */ | |
878 | tmo >>= 1; | |
879 | rthp = &rth->dst.rt_next; | |
880 | length += has_noalias(rt_hash_table[i].chain, rth); | |
9f28a2fc ED |
881 | } |
882 | spin_unlock_bh(rt_hash_lock_addr(i)); | |
883 | sum += length; | |
884 | sum2 += length*length; | |
885 | } | |
886 | if (samples) { | |
887 | unsigned long avg = sum / samples; | |
888 | unsigned long sd = int_sqrt(sum2 / samples - avg*avg); | |
889 | rt_chain_length_max = max_t(unsigned long, | |
890 | ip_rt_gc_elasticity, | |
891 | (avg + 4*sd) >> FRACT_BITS); | |
892 | } | |
893 | rover = i; | |
894 | } | |
895 | ||
896 | /* | |
897 | * rt_worker_func() is run in process context. | |
898 | * we call rt_check_expire() to scan part of the hash table | |
899 | */ | |
900 | static void rt_worker_func(struct work_struct *work) | |
901 | { | |
902 | rt_check_expire(); | |
903 | schedule_delayed_work(&expires_work, ip_rt_gc_interval); | |
904 | } | |
905 | ||
29e75252 | 906 | /* |
25985edc | 907 | * Perturbation of rt_genid by a small quantity [1..256] |
29e75252 ED |
908 | * Using 8 bits of shuffling ensure we can call rt_cache_invalidate() |
909 | * many times (2^24) without giving recent rt_genid. | |
910 | * Jenkins hash is strong enough that litle changes of rt_genid are OK. | |
1da177e4 | 911 | */ |
86c657f6 | 912 | static void rt_cache_invalidate(struct net *net) |
1da177e4 | 913 | { |
29e75252 | 914 | unsigned char shuffle; |
1da177e4 | 915 | |
29e75252 | 916 | get_random_bytes(&shuffle, sizeof(shuffle)); |
e84f84f2 | 917 | atomic_add(shuffle + 1U, &net->ipv4.rt_genid); |
b48c80ec | 918 | inetpeer_invalidate_family(AF_INET); |
1da177e4 LT |
919 | } |
920 | ||
29e75252 ED |
921 | /* |
922 | * delay < 0 : invalidate cache (fast : entries will be deleted later) | |
923 | * delay >= 0 : invalidate & flush cache (can be long) | |
924 | */ | |
76e6ebfb | 925 | void rt_cache_flush(struct net *net, int delay) |
1da177e4 | 926 | { |
86c657f6 | 927 | rt_cache_invalidate(net); |
29e75252 | 928 | if (delay >= 0) |
6561a3b1 | 929 | rt_do_flush(net, !in_softirq()); |
1da177e4 LT |
930 | } |
931 | ||
a5ee1551 | 932 | /* Flush previous cache invalidated entries from the cache */ |
6561a3b1 | 933 | void rt_cache_flush_batch(struct net *net) |
a5ee1551 | 934 | { |
6561a3b1 | 935 | rt_do_flush(net, !in_softirq()); |
a5ee1551 EB |
936 | } |
937 | ||
1080d709 NH |
938 | static void rt_emergency_hash_rebuild(struct net *net) |
939 | { | |
e87cc472 | 940 | net_warn_ratelimited("Route hash chain too long!\n"); |
3ee94372 | 941 | rt_cache_invalidate(net); |
1080d709 NH |
942 | } |
943 | ||
1da177e4 LT |
944 | /* |
945 | Short description of GC goals. | |
946 | ||
947 | We want to build algorithm, which will keep routing cache | |
948 | at some equilibrium point, when number of aged off entries | |
949 | is kept approximately equal to newly generated ones. | |
950 | ||
951 | Current expiration strength is variable "expire". | |
952 | We try to adjust it dynamically, so that if networking | |
953 | is idle expires is large enough to keep enough of warm entries, | |
954 | and when load increases it reduces to limit cache size. | |
955 | */ | |
956 | ||
569d3645 | 957 | static int rt_garbage_collect(struct dst_ops *ops) |
1da177e4 LT |
958 | { |
959 | static unsigned long expire = RT_GC_TIMEOUT; | |
960 | static unsigned long last_gc; | |
961 | static int rover; | |
962 | static int equilibrium; | |
1c31720a ED |
963 | struct rtable *rth; |
964 | struct rtable __rcu **rthp; | |
1da177e4 LT |
965 | unsigned long now = jiffies; |
966 | int goal; | |
fc66f95c | 967 | int entries = dst_entries_get_fast(&ipv4_dst_ops); |
1da177e4 LT |
968 | |
969 | /* | |
970 | * Garbage collection is pretty expensive, | |
971 | * do not make it too frequently. | |
972 | */ | |
973 | ||
974 | RT_CACHE_STAT_INC(gc_total); | |
975 | ||
976 | if (now - last_gc < ip_rt_gc_min_interval && | |
fc66f95c | 977 | entries < ip_rt_max_size) { |
1da177e4 LT |
978 | RT_CACHE_STAT_INC(gc_ignored); |
979 | goto out; | |
980 | } | |
981 | ||
fc66f95c | 982 | entries = dst_entries_get_slow(&ipv4_dst_ops); |
1da177e4 | 983 | /* Calculate number of entries, which we want to expire now. */ |
fc66f95c | 984 | goal = entries - (ip_rt_gc_elasticity << rt_hash_log); |
1da177e4 LT |
985 | if (goal <= 0) { |
986 | if (equilibrium < ipv4_dst_ops.gc_thresh) | |
987 | equilibrium = ipv4_dst_ops.gc_thresh; | |
fc66f95c | 988 | goal = entries - equilibrium; |
1da177e4 | 989 | if (goal > 0) { |
b790cedd | 990 | equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 991 | goal = entries - equilibrium; |
1da177e4 LT |
992 | } |
993 | } else { | |
994 | /* We are in dangerous area. Try to reduce cache really | |
995 | * aggressively. | |
996 | */ | |
b790cedd | 997 | goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1); |
fc66f95c | 998 | equilibrium = entries - goal; |
1da177e4 LT |
999 | } |
1000 | ||
1001 | if (now - last_gc >= ip_rt_gc_min_interval) | |
1002 | last_gc = now; | |
1003 | ||
1004 | if (goal <= 0) { | |
1005 | equilibrium += goal; | |
1006 | goto work_done; | |
1007 | } | |
1008 | ||
1009 | do { | |
1010 | int i, k; | |
1011 | ||
1012 | for (i = rt_hash_mask, k = rover; i >= 0; i--) { | |
1013 | unsigned long tmo = expire; | |
1014 | ||
1015 | k = (k + 1) & rt_hash_mask; | |
1016 | rthp = &rt_hash_table[k].chain; | |
22c047cc | 1017 | spin_lock_bh(rt_hash_lock_addr(k)); |
1c31720a ED |
1018 | while ((rth = rcu_dereference_protected(*rthp, |
1019 | lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) { | |
e84f84f2 | 1020 | if (!rt_is_expired(rth) && |
29e75252 | 1021 | !rt_may_expire(rth, tmo, expire)) { |
1da177e4 | 1022 | tmo >>= 1; |
d8d1f30b | 1023 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1024 | continue; |
1025 | } | |
d8d1f30b | 1026 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1027 | rt_free(rth); |
1028 | goal--; | |
1da177e4 | 1029 | } |
22c047cc | 1030 | spin_unlock_bh(rt_hash_lock_addr(k)); |
1da177e4 LT |
1031 | if (goal <= 0) |
1032 | break; | |
1033 | } | |
1034 | rover = k; | |
1035 | ||
1036 | if (goal <= 0) | |
1037 | goto work_done; | |
1038 | ||
1039 | /* Goal is not achieved. We stop process if: | |
1040 | ||
1041 | - if expire reduced to zero. Otherwise, expire is halfed. | |
1042 | - if table is not full. | |
1043 | - if we are called from interrupt. | |
1044 | - jiffies check is just fallback/debug loop breaker. | |
1045 | We will not spin here for long time in any case. | |
1046 | */ | |
1047 | ||
1048 | RT_CACHE_STAT_INC(gc_goal_miss); | |
1049 | ||
1050 | if (expire == 0) | |
1051 | break; | |
1052 | ||
1053 | expire >>= 1; | |
1da177e4 | 1054 | |
fc66f95c | 1055 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1da177e4 LT |
1056 | goto out; |
1057 | } while (!in_softirq() && time_before_eq(jiffies, now)); | |
1058 | ||
fc66f95c ED |
1059 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) |
1060 | goto out; | |
1061 | if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size) | |
1da177e4 | 1062 | goto out; |
e87cc472 | 1063 | net_warn_ratelimited("dst cache overflow\n"); |
1da177e4 LT |
1064 | RT_CACHE_STAT_INC(gc_dst_overflow); |
1065 | return 1; | |
1066 | ||
1067 | work_done: | |
1068 | expire += ip_rt_gc_min_interval; | |
1069 | if (expire > ip_rt_gc_timeout || | |
fc66f95c ED |
1070 | dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh || |
1071 | dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh) | |
1da177e4 | 1072 | expire = ip_rt_gc_timeout; |
1da177e4 LT |
1073 | out: return 0; |
1074 | } | |
1075 | ||
98376387 ED |
1076 | /* |
1077 | * Returns number of entries in a hash chain that have different hash_inputs | |
1078 | */ | |
1079 | static int slow_chain_length(const struct rtable *head) | |
1080 | { | |
1081 | int length = 0; | |
1082 | const struct rtable *rth = head; | |
1083 | ||
1084 | while (rth) { | |
1085 | length += has_noalias(head, rth); | |
1c31720a | 1086 | rth = rcu_dereference_protected(rth->dst.rt_next, 1); |
98376387 ED |
1087 | } |
1088 | return length >> FRACT_BITS; | |
1089 | } | |
1090 | ||
f894cbf8 DM |
1091 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, |
1092 | struct sk_buff *skb, | |
1093 | const void *daddr) | |
3769cffb | 1094 | { |
d3aaeb38 DM |
1095 | struct net_device *dev = dst->dev; |
1096 | const __be32 *pkey = daddr; | |
39232973 | 1097 | const struct rtable *rt; |
3769cffb DM |
1098 | struct neighbour *n; |
1099 | ||
39232973 | 1100 | rt = (const struct rtable *) dst; |
a263b309 | 1101 | if (rt->rt_gateway) |
39232973 | 1102 | pkey = (const __be32 *) &rt->rt_gateway; |
f894cbf8 DM |
1103 | else if (skb) |
1104 | pkey = &ip_hdr(skb)->daddr; | |
d3aaeb38 | 1105 | |
80703d26 | 1106 | n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey); |
d3aaeb38 DM |
1107 | if (n) |
1108 | return n; | |
32092ecf | 1109 | return neigh_create(&arp_tbl, pkey, dev); |
d3aaeb38 DM |
1110 | } |
1111 | ||
95c96174 | 1112 | static struct rtable *rt_intern_hash(unsigned int hash, struct rtable *rt, |
b23dd4fe | 1113 | struct sk_buff *skb, int ifindex) |
1da177e4 | 1114 | { |
1c31720a ED |
1115 | struct rtable *rth, *cand; |
1116 | struct rtable __rcu **rthp, **candp; | |
1da177e4 | 1117 | unsigned long now; |
1da177e4 LT |
1118 | u32 min_score; |
1119 | int chain_length; | |
1da177e4 LT |
1120 | |
1121 | restart: | |
1122 | chain_length = 0; | |
1123 | min_score = ~(u32)0; | |
1124 | cand = NULL; | |
1125 | candp = NULL; | |
1126 | now = jiffies; | |
1127 | ||
7586eceb | 1128 | if (!rt_caching(dev_net(rt->dst.dev)) || (rt->dst.flags & DST_NOCACHE)) { |
73e42897 NH |
1129 | /* |
1130 | * If we're not caching, just tell the caller we | |
1131 | * were successful and don't touch the route. The | |
1132 | * caller hold the sole reference to the cache entry, and | |
1133 | * it will be released when the caller is done with it. | |
1134 | * If we drop it here, the callers have no way to resolve routes | |
1135 | * when we're not caching. Instead, just point *rp at rt, so | |
1136 | * the caller gets a single use out of the route | |
b6280b47 NH |
1137 | * Note that we do rt_free on this new route entry, so that |
1138 | * once its refcount hits zero, we are still able to reap it | |
1139 | * (Thanks Alexey) | |
27b75c95 ED |
1140 | * Note: To avoid expensive rcu stuff for this uncached dst, |
1141 | * we set DST_NOCACHE so that dst_release() can free dst without | |
1142 | * waiting a grace period. | |
73e42897 | 1143 | */ |
b6280b47 | 1144 | |
c7d4426a | 1145 | rt->dst.flags |= DST_NOCACHE; |
b6280b47 | 1146 | goto skip_hashing; |
1080d709 NH |
1147 | } |
1148 | ||
1da177e4 LT |
1149 | rthp = &rt_hash_table[hash].chain; |
1150 | ||
22c047cc | 1151 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1c31720a ED |
1152 | while ((rth = rcu_dereference_protected(*rthp, |
1153 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1154 | if (rt_is_expired(rth)) { |
d8d1f30b | 1155 | *rthp = rth->dst.rt_next; |
29e75252 ED |
1156 | rt_free(rth); |
1157 | continue; | |
1158 | } | |
5e2b61f7 | 1159 | if (compare_keys(rth, rt) && compare_netns(rth, rt)) { |
1da177e4 | 1160 | /* Put it first */ |
d8d1f30b | 1161 | *rthp = rth->dst.rt_next; |
1da177e4 LT |
1162 | /* |
1163 | * Since lookup is lockfree, the deletion | |
1164 | * must be visible to another weakly ordered CPU before | |
1165 | * the insertion at the start of the hash chain. | |
1166 | */ | |
d8d1f30b | 1167 | rcu_assign_pointer(rth->dst.rt_next, |
1da177e4 LT |
1168 | rt_hash_table[hash].chain); |
1169 | /* | |
1170 | * Since lookup is lockfree, the update writes | |
1171 | * must be ordered for consistency on SMP. | |
1172 | */ | |
1173 | rcu_assign_pointer(rt_hash_table[hash].chain, rth); | |
1174 | ||
d8d1f30b | 1175 | dst_use(&rth->dst, now); |
22c047cc | 1176 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1177 | |
1178 | rt_drop(rt); | |
b23dd4fe | 1179 | if (skb) |
d8d1f30b | 1180 | skb_dst_set(skb, &rth->dst); |
b23dd4fe | 1181 | return rth; |
1da177e4 LT |
1182 | } |
1183 | ||
d8d1f30b | 1184 | if (!atomic_read(&rth->dst.__refcnt)) { |
1da177e4 LT |
1185 | u32 score = rt_score(rth); |
1186 | ||
1187 | if (score <= min_score) { | |
1188 | cand = rth; | |
1189 | candp = rthp; | |
1190 | min_score = score; | |
1191 | } | |
1192 | } | |
1193 | ||
1194 | chain_length++; | |
1195 | ||
d8d1f30b | 1196 | rthp = &rth->dst.rt_next; |
1da177e4 LT |
1197 | } |
1198 | ||
1199 | if (cand) { | |
1200 | /* ip_rt_gc_elasticity used to be average length of chain | |
1201 | * length, when exceeded gc becomes really aggressive. | |
1202 | * | |
1203 | * The second limit is less certain. At the moment it allows | |
1204 | * only 2 entries per bucket. We will see. | |
1205 | */ | |
1206 | if (chain_length > ip_rt_gc_elasticity) { | |
d8d1f30b | 1207 | *candp = cand->dst.rt_next; |
1da177e4 LT |
1208 | rt_free(cand); |
1209 | } | |
1080d709 | 1210 | } else { |
98376387 ED |
1211 | if (chain_length > rt_chain_length_max && |
1212 | slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) { | |
d8d1f30b | 1213 | struct net *net = dev_net(rt->dst.dev); |
1080d709 | 1214 | int num = ++net->ipv4.current_rt_cache_rebuild_count; |
b35ecb5d | 1215 | if (!rt_caching(net)) { |
058bd4d2 | 1216 | pr_warn("%s: %d rebuilds is over limit, route caching disabled\n", |
d8d1f30b | 1217 | rt->dst.dev->name, num); |
1080d709 | 1218 | } |
b35ecb5d | 1219 | rt_emergency_hash_rebuild(net); |
6a2bad70 PE |
1220 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1221 | ||
5e2b61f7 | 1222 | hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
6a2bad70 PE |
1223 | ifindex, rt_genid(net)); |
1224 | goto restart; | |
1080d709 | 1225 | } |
1da177e4 LT |
1226 | } |
1227 | ||
d8d1f30b | 1228 | rt->dst.rt_next = rt_hash_table[hash].chain; |
1080d709 | 1229 | |
00269b54 ED |
1230 | /* |
1231 | * Since lookup is lockfree, we must make sure | |
25985edc | 1232 | * previous writes to rt are committed to memory |
00269b54 ED |
1233 | * before making rt visible to other CPUS. |
1234 | */ | |
1ddbcb00 | 1235 | rcu_assign_pointer(rt_hash_table[hash].chain, rt); |
1080d709 | 1236 | |
22c047cc | 1237 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
73e42897 | 1238 | |
b6280b47 | 1239 | skip_hashing: |
b23dd4fe | 1240 | if (skb) |
d8d1f30b | 1241 | skb_dst_set(skb, &rt->dst); |
b23dd4fe | 1242 | return rt; |
1da177e4 LT |
1243 | } |
1244 | ||
6431cbc2 DM |
1245 | static atomic_t __rt_peer_genid = ATOMIC_INIT(0); |
1246 | ||
1247 | static u32 rt_peer_genid(void) | |
1248 | { | |
1249 | return atomic_read(&__rt_peer_genid); | |
1250 | } | |
1251 | ||
a48eff12 | 1252 | void rt_bind_peer(struct rtable *rt, __be32 daddr, int create) |
1da177e4 | 1253 | { |
97bab73f | 1254 | struct inet_peer_base *base; |
1da177e4 LT |
1255 | struct inet_peer *peer; |
1256 | ||
97bab73f DM |
1257 | base = inetpeer_base_ptr(rt->_peer); |
1258 | if (!base) | |
1259 | return; | |
1260 | ||
1261 | peer = inet_getpeer_v4(base, daddr, create); | |
7b34ca2a DM |
1262 | if (peer) { |
1263 | if (!rt_set_peer(rt, peer)) | |
1264 | inet_putpeer(peer); | |
1265 | else | |
1266 | rt->rt_peer_genid = rt_peer_genid(); | |
1267 | } | |
1da177e4 LT |
1268 | } |
1269 | ||
1270 | /* | |
1271 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
1272 | * we still can generate some output. | |
1273 | * Random ID selection looks a bit dangerous because we have no chances to | |
1274 | * select ID being unique in a reasonable period of time. | |
1275 | * But broken packet identifier may be better than no packet at all. | |
1276 | */ | |
1277 | static void ip_select_fb_ident(struct iphdr *iph) | |
1278 | { | |
1279 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
1280 | static u32 ip_fallback_id; | |
1281 | u32 salt; | |
1282 | ||
1283 | spin_lock_bh(&ip_fb_id_lock); | |
e448515c | 1284 | salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr); |
1da177e4 LT |
1285 | iph->id = htons(salt & 0xFFFF); |
1286 | ip_fallback_id = salt; | |
1287 | spin_unlock_bh(&ip_fb_id_lock); | |
1288 | } | |
1289 | ||
1290 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
1291 | { | |
1d861aa4 DM |
1292 | struct net *net = dev_net(dst->dev); |
1293 | struct inet_peer *peer; | |
1da177e4 | 1294 | |
1d861aa4 DM |
1295 | peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1); |
1296 | if (peer) { | |
1297 | iph->id = htons(inet_getid(peer, more)); | |
1298 | inet_putpeer(peer); | |
1299 | return; | |
1300 | } | |
1da177e4 LT |
1301 | |
1302 | ip_select_fb_ident(iph); | |
1303 | } | |
4bc2f18b | 1304 | EXPORT_SYMBOL(__ip_select_ident); |
1da177e4 | 1305 | |
95c96174 | 1306 | static void rt_del(unsigned int hash, struct rtable *rt) |
1da177e4 | 1307 | { |
1c31720a ED |
1308 | struct rtable __rcu **rthp; |
1309 | struct rtable *aux; | |
1da177e4 | 1310 | |
29e75252 | 1311 | rthp = &rt_hash_table[hash].chain; |
22c047cc | 1312 | spin_lock_bh(rt_hash_lock_addr(hash)); |
1da177e4 | 1313 | ip_rt_put(rt); |
1c31720a ED |
1314 | while ((aux = rcu_dereference_protected(*rthp, |
1315 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
e84f84f2 | 1316 | if (aux == rt || rt_is_expired(aux)) { |
d8d1f30b | 1317 | *rthp = aux->dst.rt_next; |
29e75252 ED |
1318 | rt_free(aux); |
1319 | continue; | |
1da177e4 | 1320 | } |
d8d1f30b | 1321 | rthp = &aux->dst.rt_next; |
29e75252 | 1322 | } |
22c047cc | 1323 | spin_unlock_bh(rt_hash_lock_addr(hash)); |
1da177e4 LT |
1324 | } |
1325 | ||
de398fb8 | 1326 | static void check_peer_redir(struct dst_entry *dst, struct inet_peer *peer) |
9cc20b26 ED |
1327 | { |
1328 | struct rtable *rt = (struct rtable *) dst; | |
1329 | __be32 orig_gw = rt->rt_gateway; | |
f187bc6e | 1330 | struct neighbour *n; |
9cc20b26 ED |
1331 | |
1332 | dst_confirm(&rt->dst); | |
1333 | ||
1334 | rt->rt_gateway = peer->redirect_learned.a4; | |
1335 | ||
f894cbf8 | 1336 | n = ipv4_neigh_lookup(&rt->dst, NULL, &rt->rt_gateway); |
f187bc6e | 1337 | if (!n) { |
de398fb8 DM |
1338 | rt->rt_gateway = orig_gw; |
1339 | return; | |
1340 | } | |
de398fb8 DM |
1341 | if (!(n->nud_state & NUD_VALID)) { |
1342 | neigh_event_send(n, NULL); | |
9cc20b26 ED |
1343 | } else { |
1344 | rt->rt_flags |= RTCF_REDIRECTED; | |
1345 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); | |
1346 | } | |
f187bc6e | 1347 | neigh_release(n); |
9cc20b26 ED |
1348 | } |
1349 | ||
ed7865a4 | 1350 | /* called in rcu_read_lock() section */ |
f7655229 AV |
1351 | void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, |
1352 | __be32 saddr, struct net_device *dev) | |
1da177e4 | 1353 | { |
7cc9150e | 1354 | int s, i; |
ed7865a4 | 1355 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
7cc9150e FL |
1356 | __be32 skeys[2] = { saddr, 0 }; |
1357 | int ikeys[2] = { dev->ifindex, 0 }; | |
f39925db | 1358 | struct inet_peer *peer; |
317805b8 | 1359 | struct net *net; |
1da177e4 | 1360 | |
1da177e4 LT |
1361 | if (!in_dev) |
1362 | return; | |
1363 | ||
c346dca1 | 1364 | net = dev_net(dev); |
9d4fb27d JP |
1365 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || |
1366 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
1367 | ipv4_is_zeronet(new_gw)) | |
1da177e4 LT |
1368 | goto reject_redirect; |
1369 | ||
1370 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
1371 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
1372 | goto reject_redirect; | |
1373 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
1374 | goto reject_redirect; | |
1375 | } else { | |
317805b8 | 1376 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) |
1da177e4 LT |
1377 | goto reject_redirect; |
1378 | } | |
1379 | ||
7cc9150e FL |
1380 | for (s = 0; s < 2; s++) { |
1381 | for (i = 0; i < 2; i++) { | |
9cc20b26 ED |
1382 | unsigned int hash; |
1383 | struct rtable __rcu **rthp; | |
1384 | struct rtable *rt; | |
1385 | ||
1386 | hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net)); | |
1387 | ||
1388 | rthp = &rt_hash_table[hash].chain; | |
1389 | ||
1390 | while ((rt = rcu_dereference(*rthp)) != NULL) { | |
1391 | rthp = &rt->dst.rt_next; | |
1392 | ||
1393 | if (rt->rt_key_dst != daddr || | |
1394 | rt->rt_key_src != skeys[s] || | |
1395 | rt->rt_oif != ikeys[i] || | |
1396 | rt_is_input_route(rt) || | |
1397 | rt_is_expired(rt) || | |
1398 | !net_eq(dev_net(rt->dst.dev), net) || | |
1399 | rt->dst.error || | |
1400 | rt->dst.dev != dev || | |
1401 | rt->rt_gateway != old_gw) | |
1402 | continue; | |
e905a9ed | 1403 | |
fbfe95a4 | 1404 | peer = rt_get_peer_create(rt, rt->rt_dst); |
9cc20b26 | 1405 | if (peer) { |
ac3f48de | 1406 | if (peer->redirect_learned.a4 != new_gw) { |
9cc20b26 ED |
1407 | peer->redirect_learned.a4 = new_gw; |
1408 | atomic_inc(&__rt_peer_genid); | |
1409 | } | |
1410 | check_peer_redir(&rt->dst, peer); | |
1411 | } | |
7cc9150e | 1412 | } |
7cc9150e | 1413 | } |
1da177e4 | 1414 | } |
1da177e4 LT |
1415 | return; |
1416 | ||
1417 | reject_redirect: | |
1418 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
e87cc472 JP |
1419 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
1420 | net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n" | |
1421 | " Advised path = %pI4 -> %pI4\n", | |
1422 | &old_gw, dev->name, &new_gw, | |
1423 | &saddr, &daddr); | |
1da177e4 | 1424 | #endif |
ed7865a4 | 1425 | ; |
1da177e4 LT |
1426 | } |
1427 | ||
fe6fe792 ED |
1428 | static bool peer_pmtu_expired(struct inet_peer *peer) |
1429 | { | |
1430 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1431 | ||
1432 | return orig && | |
1433 | time_after_eq(jiffies, orig) && | |
1434 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1435 | } | |
1436 | ||
1437 | static bool peer_pmtu_cleaned(struct inet_peer *peer) | |
1438 | { | |
1439 | unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); | |
1440 | ||
1441 | return orig && | |
1442 | cmpxchg(&peer->pmtu_expires, orig, 0) == orig; | |
1443 | } | |
1444 | ||
1da177e4 LT |
1445 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) |
1446 | { | |
ee6b9673 | 1447 | struct rtable *rt = (struct rtable *)dst; |
1da177e4 LT |
1448 | struct dst_entry *ret = dst; |
1449 | ||
1450 | if (rt) { | |
d11a4dc1 | 1451 | if (dst->obsolete > 0) { |
1da177e4 LT |
1452 | ip_rt_put(rt); |
1453 | ret = NULL; | |
2c8cec5c | 1454 | } else if (rt->rt_flags & RTCF_REDIRECTED) { |
95c96174 | 1455 | unsigned int hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, |
5e2b61f7 | 1456 | rt->rt_oif, |
e84f84f2 | 1457 | rt_genid(dev_net(dst->dev))); |
1da177e4 LT |
1458 | rt_del(hash, rt); |
1459 | ret = NULL; | |
97bab73f DM |
1460 | } else if (rt_has_peer(rt)) { |
1461 | struct inet_peer *peer = rt_peer_ptr(rt); | |
1462 | if (peer_pmtu_expired(peer)) | |
1463 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); | |
1da177e4 LT |
1464 | } |
1465 | } | |
1466 | return ret; | |
1467 | } | |
1468 | ||
1469 | /* | |
1470 | * Algorithm: | |
1471 | * 1. The first ip_rt_redirect_number redirects are sent | |
1472 | * with exponential backoff, then we stop sending them at all, | |
1473 | * assuming that the host ignores our redirects. | |
1474 | * 2. If we did not see packets requiring redirects | |
1475 | * during ip_rt_redirect_silence, we assume that the host | |
1476 | * forgot redirected route and start to send redirects again. | |
1477 | * | |
1478 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
1479 | * in icmp.c. | |
1480 | * | |
1481 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
1482 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
1483 | */ | |
1484 | ||
1485 | void ip_rt_send_redirect(struct sk_buff *skb) | |
1486 | { | |
511c3f92 | 1487 | struct rtable *rt = skb_rtable(skb); |
30038fc6 | 1488 | struct in_device *in_dev; |
92d86829 | 1489 | struct inet_peer *peer; |
1d861aa4 | 1490 | struct net *net; |
30038fc6 | 1491 | int log_martians; |
1da177e4 | 1492 | |
30038fc6 | 1493 | rcu_read_lock(); |
d8d1f30b | 1494 | in_dev = __in_dev_get_rcu(rt->dst.dev); |
30038fc6 ED |
1495 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { |
1496 | rcu_read_unlock(); | |
1da177e4 | 1497 | return; |
30038fc6 ED |
1498 | } |
1499 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
1500 | rcu_read_unlock(); | |
1da177e4 | 1501 | |
1d861aa4 DM |
1502 | net = dev_net(rt->dst.dev); |
1503 | peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1); | |
92d86829 DM |
1504 | if (!peer) { |
1505 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
1506 | return; | |
1507 | } | |
1508 | ||
1da177e4 LT |
1509 | /* No redirected packets during ip_rt_redirect_silence; |
1510 | * reset the algorithm. | |
1511 | */ | |
92d86829 DM |
1512 | if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) |
1513 | peer->rate_tokens = 0; | |
1da177e4 LT |
1514 | |
1515 | /* Too many ignored redirects; do not send anything | |
d8d1f30b | 1516 | * set dst.rate_last to the last seen redirected packet. |
1da177e4 | 1517 | */ |
92d86829 DM |
1518 | if (peer->rate_tokens >= ip_rt_redirect_number) { |
1519 | peer->rate_last = jiffies; | |
1d861aa4 | 1520 | goto out_put_peer; |
1da177e4 LT |
1521 | } |
1522 | ||
1523 | /* Check for load limit; set rate_last to the latest sent | |
1524 | * redirect. | |
1525 | */ | |
92d86829 | 1526 | if (peer->rate_tokens == 0 || |
14fb8a76 | 1527 | time_after(jiffies, |
92d86829 DM |
1528 | (peer->rate_last + |
1529 | (ip_rt_redirect_load << peer->rate_tokens)))) { | |
1da177e4 | 1530 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); |
92d86829 DM |
1531 | peer->rate_last = jiffies; |
1532 | ++peer->rate_tokens; | |
1da177e4 | 1533 | #ifdef CONFIG_IP_ROUTE_VERBOSE |
30038fc6 | 1534 | if (log_martians && |
e87cc472 JP |
1535 | peer->rate_tokens == ip_rt_redirect_number) |
1536 | net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", | |
1537 | &ip_hdr(skb)->saddr, rt->rt_iif, | |
1538 | &rt->rt_dst, &rt->rt_gateway); | |
1da177e4 LT |
1539 | #endif |
1540 | } | |
1d861aa4 DM |
1541 | out_put_peer: |
1542 | inet_putpeer(peer); | |
1da177e4 LT |
1543 | } |
1544 | ||
1545 | static int ip_error(struct sk_buff *skb) | |
1546 | { | |
251da413 | 1547 | struct in_device *in_dev = __in_dev_get_rcu(skb->dev); |
511c3f92 | 1548 | struct rtable *rt = skb_rtable(skb); |
92d86829 | 1549 | struct inet_peer *peer; |
1da177e4 | 1550 | unsigned long now; |
251da413 | 1551 | struct net *net; |
92d86829 | 1552 | bool send; |
1da177e4 LT |
1553 | int code; |
1554 | ||
251da413 DM |
1555 | net = dev_net(rt->dst.dev); |
1556 | if (!IN_DEV_FORWARD(in_dev)) { | |
1557 | switch (rt->dst.error) { | |
1558 | case EHOSTUNREACH: | |
1559 | IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS); | |
1560 | break; | |
1561 | ||
1562 | case ENETUNREACH: | |
1563 | IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES); | |
1564 | break; | |
1565 | } | |
1566 | goto out; | |
1567 | } | |
1568 | ||
d8d1f30b | 1569 | switch (rt->dst.error) { |
4500ebf8 JP |
1570 | case EINVAL: |
1571 | default: | |
1572 | goto out; | |
1573 | case EHOSTUNREACH: | |
1574 | code = ICMP_HOST_UNREACH; | |
1575 | break; | |
1576 | case ENETUNREACH: | |
1577 | code = ICMP_NET_UNREACH; | |
251da413 | 1578 | IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES); |
4500ebf8 JP |
1579 | break; |
1580 | case EACCES: | |
1581 | code = ICMP_PKT_FILTERED; | |
1582 | break; | |
1da177e4 LT |
1583 | } |
1584 | ||
1d861aa4 | 1585 | peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1); |
92d86829 DM |
1586 | |
1587 | send = true; | |
1588 | if (peer) { | |
1589 | now = jiffies; | |
1590 | peer->rate_tokens += now - peer->rate_last; | |
1591 | if (peer->rate_tokens > ip_rt_error_burst) | |
1592 | peer->rate_tokens = ip_rt_error_burst; | |
1593 | peer->rate_last = now; | |
1594 | if (peer->rate_tokens >= ip_rt_error_cost) | |
1595 | peer->rate_tokens -= ip_rt_error_cost; | |
1596 | else | |
1597 | send = false; | |
1d861aa4 | 1598 | inet_putpeer(peer); |
1da177e4 | 1599 | } |
92d86829 DM |
1600 | if (send) |
1601 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1da177e4 LT |
1602 | |
1603 | out: kfree_skb(skb); | |
1604 | return 0; | |
e905a9ed | 1605 | } |
1da177e4 | 1606 | |
2c8cec5c DM |
1607 | static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer) |
1608 | { | |
fe6fe792 | 1609 | unsigned long expires = ACCESS_ONCE(peer->pmtu_expires); |
2c8cec5c | 1610 | |
fe6fe792 ED |
1611 | if (!expires) |
1612 | return; | |
46af3180 | 1613 | if (time_before(jiffies, expires)) { |
2c8cec5c DM |
1614 | u32 orig_dst_mtu = dst_mtu(dst); |
1615 | if (peer->pmtu_learned < orig_dst_mtu) { | |
1616 | if (!peer->pmtu_orig) | |
1617 | peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU); | |
1618 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned); | |
1619 | } | |
1620 | } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires) | |
1621 | dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); | |
1622 | } | |
1623 | ||
1da177e4 LT |
1624 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) |
1625 | { | |
2c8cec5c DM |
1626 | struct rtable *rt = (struct rtable *) dst; |
1627 | struct inet_peer *peer; | |
1628 | ||
1629 | dst_confirm(dst); | |
1630 | ||
fbfe95a4 | 1631 | peer = rt_get_peer_create(rt, rt->rt_dst); |
2c8cec5c | 1632 | if (peer) { |
fe6fe792 ED |
1633 | unsigned long pmtu_expires = ACCESS_ONCE(peer->pmtu_expires); |
1634 | ||
2c8cec5c | 1635 | if (mtu < ip_rt_min_pmtu) |
1da177e4 | 1636 | mtu = ip_rt_min_pmtu; |
fe6fe792 | 1637 | if (!pmtu_expires || mtu < peer->pmtu_learned) { |
46af3180 HS |
1638 | |
1639 | pmtu_expires = jiffies + ip_rt_mtu_expires; | |
1640 | if (!pmtu_expires) | |
1641 | pmtu_expires = 1UL; | |
1642 | ||
2c8cec5c | 1643 | peer->pmtu_learned = mtu; |
46af3180 | 1644 | peer->pmtu_expires = pmtu_expires; |
2c8cec5c DM |
1645 | |
1646 | atomic_inc(&__rt_peer_genid); | |
1647 | rt->rt_peer_genid = rt_peer_genid(); | |
1da177e4 | 1648 | } |
46af3180 | 1649 | check_peer_pmtu(dst, peer); |
1da177e4 LT |
1650 | } |
1651 | } | |
1652 | ||
36393395 DM |
1653 | void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, |
1654 | int oif, u32 mark, u8 protocol, int flow_flags) | |
1655 | { | |
1656 | const struct iphdr *iph = (const struct iphdr *)skb->data; | |
1657 | struct flowi4 fl4; | |
1658 | struct rtable *rt; | |
1659 | ||
1660 | flowi4_init_output(&fl4, oif, mark, RT_TOS(iph->tos), RT_SCOPE_UNIVERSE, | |
1661 | protocol, flow_flags | FLOWI_FLAG_PRECOW_METRICS, | |
1662 | iph->daddr, iph->saddr, 0, 0); | |
1663 | rt = __ip_route_output_key(net, &fl4); | |
1664 | if (!IS_ERR(rt)) { | |
1665 | ip_rt_update_pmtu(&rt->dst, mtu); | |
1666 | ip_rt_put(rt); | |
1667 | } | |
1668 | } | |
1669 | EXPORT_SYMBOL_GPL(ipv4_update_pmtu); | |
1670 | ||
1671 | void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) | |
1672 | { | |
1673 | const struct inet_sock *inet = inet_sk(sk); | |
1674 | ||
1675 | return ipv4_update_pmtu(skb, sock_net(sk), mtu, | |
1676 | sk->sk_bound_dev_if, sk->sk_mark, | |
1677 | inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, | |
1678 | inet_sk_flowi_flags(sk)); | |
1679 | } | |
1680 | EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu); | |
f39925db | 1681 | |
de398fb8 | 1682 | static void ipv4_validate_peer(struct rtable *rt) |
1da177e4 | 1683 | { |
6431cbc2 | 1684 | if (rt->rt_peer_genid != rt_peer_genid()) { |
fbfe95a4 | 1685 | struct inet_peer *peer = rt_get_peer(rt, rt->rt_dst); |
6431cbc2 | 1686 | |
fe6fe792 | 1687 | if (peer) { |
efbc368d | 1688 | check_peer_pmtu(&rt->dst, peer); |
2c8cec5c | 1689 | |
fe6fe792 | 1690 | if (peer->redirect_learned.a4 && |
de398fb8 DM |
1691 | peer->redirect_learned.a4 != rt->rt_gateway) |
1692 | check_peer_redir(&rt->dst, peer); | |
f39925db DM |
1693 | } |
1694 | ||
6431cbc2 DM |
1695 | rt->rt_peer_genid = rt_peer_genid(); |
1696 | } | |
efbc368d DM |
1697 | } |
1698 | ||
1699 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) | |
1700 | { | |
1701 | struct rtable *rt = (struct rtable *) dst; | |
1702 | ||
1703 | if (rt_is_expired(rt)) | |
1704 | return NULL; | |
de398fb8 | 1705 | ipv4_validate_peer(rt); |
d11a4dc1 | 1706 | return dst; |
1da177e4 LT |
1707 | } |
1708 | ||
1709 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1710 | { | |
1711 | struct rtable *rt = (struct rtable *) dst; | |
1da177e4 | 1712 | |
62fa8a84 DM |
1713 | if (rt->fi) { |
1714 | fib_info_put(rt->fi); | |
1715 | rt->fi = NULL; | |
1716 | } | |
97bab73f DM |
1717 | if (rt_has_peer(rt)) { |
1718 | struct inet_peer *peer = rt_peer_ptr(rt); | |
1da177e4 LT |
1719 | inet_putpeer(peer); |
1720 | } | |
1da177e4 LT |
1721 | } |
1722 | ||
1da177e4 LT |
1723 | |
1724 | static void ipv4_link_failure(struct sk_buff *skb) | |
1725 | { | |
1726 | struct rtable *rt; | |
1727 | ||
1728 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1729 | ||
511c3f92 | 1730 | rt = skb_rtable(skb); |
97bab73f DM |
1731 | if (rt && rt_has_peer(rt)) { |
1732 | struct inet_peer *peer = rt_peer_ptr(rt); | |
1733 | if (peer_pmtu_cleaned(peer)) | |
1734 | dst_metric_set(&rt->dst, RTAX_MTU, peer->pmtu_orig); | |
1735 | } | |
1da177e4 LT |
1736 | } |
1737 | ||
1738 | static int ip_rt_bug(struct sk_buff *skb) | |
1739 | { | |
91df42be JP |
1740 | pr_debug("%s: %pI4 -> %pI4, %s\n", |
1741 | __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1742 | skb->dev ? skb->dev->name : "?"); | |
1da177e4 | 1743 | kfree_skb(skb); |
c378a9c0 | 1744 | WARN_ON(1); |
1da177e4 LT |
1745 | return 0; |
1746 | } | |
1747 | ||
1748 | /* | |
1749 | We do not cache source address of outgoing interface, | |
1750 | because it is used only by IP RR, TS and SRR options, | |
1751 | so that it out of fast path. | |
1752 | ||
1753 | BTW remember: "addr" is allowed to be not aligned | |
1754 | in IP options! | |
1755 | */ | |
1756 | ||
8e36360a | 1757 | void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) |
1da177e4 | 1758 | { |
a61ced5d | 1759 | __be32 src; |
1da177e4 | 1760 | |
c7537967 | 1761 | if (rt_is_output_route(rt)) |
c5be24ff | 1762 | src = ip_hdr(skb)->saddr; |
ebc0ffae | 1763 | else { |
8e36360a DM |
1764 | struct fib_result res; |
1765 | struct flowi4 fl4; | |
1766 | struct iphdr *iph; | |
1767 | ||
1768 | iph = ip_hdr(skb); | |
1769 | ||
1770 | memset(&fl4, 0, sizeof(fl4)); | |
1771 | fl4.daddr = iph->daddr; | |
1772 | fl4.saddr = iph->saddr; | |
b0fe4a31 | 1773 | fl4.flowi4_tos = RT_TOS(iph->tos); |
8e36360a DM |
1774 | fl4.flowi4_oif = rt->dst.dev->ifindex; |
1775 | fl4.flowi4_iif = skb->dev->ifindex; | |
1776 | fl4.flowi4_mark = skb->mark; | |
5e2b61f7 | 1777 | |
ebc0ffae | 1778 | rcu_read_lock(); |
68a5e3dd | 1779 | if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0) |
436c3b66 | 1780 | src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); |
ebc0ffae ED |
1781 | else |
1782 | src = inet_select_addr(rt->dst.dev, rt->rt_gateway, | |
1da177e4 | 1783 | RT_SCOPE_UNIVERSE); |
ebc0ffae ED |
1784 | rcu_read_unlock(); |
1785 | } | |
1da177e4 LT |
1786 | memcpy(addr, &src, 4); |
1787 | } | |
1788 | ||
c7066f70 | 1789 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1790 | static void set_class_tag(struct rtable *rt, u32 tag) |
1791 | { | |
d8d1f30b CG |
1792 | if (!(rt->dst.tclassid & 0xFFFF)) |
1793 | rt->dst.tclassid |= tag & 0xFFFF; | |
1794 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1795 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1da177e4 LT |
1796 | } |
1797 | #endif | |
1798 | ||
0dbaee3b DM |
1799 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst) |
1800 | { | |
1801 | unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS); | |
1802 | ||
1803 | if (advmss == 0) { | |
1804 | advmss = max_t(unsigned int, dst->dev->mtu - 40, | |
1805 | ip_rt_min_advmss); | |
1806 | if (advmss > 65535 - 40) | |
1807 | advmss = 65535 - 40; | |
1808 | } | |
1809 | return advmss; | |
1810 | } | |
1811 | ||
ebb762f2 | 1812 | static unsigned int ipv4_mtu(const struct dst_entry *dst) |
d33e4553 | 1813 | { |
261663b0 | 1814 | const struct rtable *rt = (const struct rtable *) dst; |
618f9bc7 SK |
1815 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
1816 | ||
261663b0 | 1817 | if (mtu && rt_is_output_route(rt)) |
618f9bc7 SK |
1818 | return mtu; |
1819 | ||
1820 | mtu = dst->dev->mtu; | |
d33e4553 DM |
1821 | |
1822 | if (unlikely(dst_metric_locked(dst, RTAX_MTU))) { | |
d33e4553 DM |
1823 | |
1824 | if (rt->rt_gateway != rt->rt_dst && mtu > 576) | |
1825 | mtu = 576; | |
1826 | } | |
1827 | ||
1828 | if (mtu > IP_MAX_MTU) | |
1829 | mtu = IP_MAX_MTU; | |
1830 | ||
1831 | return mtu; | |
1832 | } | |
1833 | ||
813b3b5d | 1834 | static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1835 | struct fib_info *fi) |
a4daad6b | 1836 | { |
97bab73f | 1837 | struct inet_peer_base *base; |
0131ba45 DM |
1838 | struct inet_peer *peer; |
1839 | int create = 0; | |
a4daad6b | 1840 | |
0131ba45 DM |
1841 | /* If a peer entry exists for this destination, we must hook |
1842 | * it up in order to get at cached metrics. | |
1843 | */ | |
813b3b5d | 1844 | if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS)) |
0131ba45 DM |
1845 | create = 1; |
1846 | ||
97bab73f DM |
1847 | base = inetpeer_base_ptr(rt->_peer); |
1848 | BUG_ON(!base); | |
1849 | ||
1850 | peer = inet_getpeer_v4(base, rt->rt_dst, create); | |
0131ba45 | 1851 | if (peer) { |
97bab73f | 1852 | __rt_set_peer(rt, peer); |
3c0afdca | 1853 | rt->rt_peer_genid = rt_peer_genid(); |
a4daad6b DM |
1854 | if (inet_metrics_new(peer)) |
1855 | memcpy(peer->metrics, fi->fib_metrics, | |
1856 | sizeof(u32) * RTAX_MAX); | |
1857 | dst_init_metrics(&rt->dst, peer->metrics, false); | |
2c8cec5c | 1858 | |
fe6fe792 | 1859 | check_peer_pmtu(&rt->dst, peer); |
ac3f48de | 1860 | |
f39925db DM |
1861 | if (peer->redirect_learned.a4 && |
1862 | peer->redirect_learned.a4 != rt->rt_gateway) { | |
1863 | rt->rt_gateway = peer->redirect_learned.a4; | |
1864 | rt->rt_flags |= RTCF_REDIRECTED; | |
1865 | } | |
0131ba45 DM |
1866 | } else { |
1867 | if (fi->fib_metrics != (u32 *) dst_default_metrics) { | |
1868 | rt->fi = fi; | |
1869 | atomic_inc(&fi->fib_clntref); | |
1870 | } | |
1871 | dst_init_metrics(&rt->dst, fi->fib_metrics, true); | |
a4daad6b DM |
1872 | } |
1873 | } | |
1874 | ||
813b3b5d | 1875 | static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4, |
5e2b61f7 | 1876 | const struct fib_result *res, |
982721f3 | 1877 | struct fib_info *fi, u16 type, u32 itag) |
1da177e4 | 1878 | { |
defb3519 | 1879 | struct dst_entry *dst = &rt->dst; |
1da177e4 LT |
1880 | |
1881 | if (fi) { | |
1882 | if (FIB_RES_GW(*res) && | |
1883 | FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
1884 | rt->rt_gateway = FIB_RES_GW(*res); | |
813b3b5d | 1885 | rt_init_metrics(rt, fl4, fi); |
c7066f70 | 1886 | #ifdef CONFIG_IP_ROUTE_CLASSID |
defb3519 | 1887 | dst->tclassid = FIB_RES_NH(*res).nh_tclassid; |
1da177e4 | 1888 | #endif |
d33e4553 | 1889 | } |
defb3519 | 1890 | |
defb3519 DM |
1891 | if (dst_mtu(dst) > IP_MAX_MTU) |
1892 | dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU); | |
1da177e4 | 1893 | |
c7066f70 | 1894 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1895 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
1896 | set_class_tag(rt, fib_rules_tclass(res)); | |
1897 | #endif | |
1898 | set_class_tag(rt, itag); | |
1899 | #endif | |
1da177e4 LT |
1900 | } |
1901 | ||
5c1e6aa3 DM |
1902 | static struct rtable *rt_dst_alloc(struct net_device *dev, |
1903 | bool nopolicy, bool noxfrm) | |
0c4dcd58 | 1904 | { |
5c1e6aa3 DM |
1905 | return dst_alloc(&ipv4_dst_ops, dev, 1, -1, |
1906 | DST_HOST | | |
1907 | (nopolicy ? DST_NOPOLICY : 0) | | |
1908 | (noxfrm ? DST_NOXFRM : 0)); | |
0c4dcd58 DM |
1909 | } |
1910 | ||
96d36220 | 1911 | /* called in rcu_read_lock() section */ |
9e12bb22 | 1912 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
1913 | u8 tos, struct net_device *dev, int our) |
1914 | { | |
96d36220 | 1915 | unsigned int hash; |
1da177e4 | 1916 | struct rtable *rth; |
96d36220 | 1917 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 1918 | u32 itag = 0; |
b5f7e755 | 1919 | int err; |
1da177e4 LT |
1920 | |
1921 | /* Primary sanity checks. */ | |
1922 | ||
1923 | if (in_dev == NULL) | |
1924 | return -EINVAL; | |
1925 | ||
1e637c74 | 1926 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
d0daebc3 | 1927 | skb->protocol != htons(ETH_P_IP)) |
1da177e4 LT |
1928 | goto e_inval; |
1929 | ||
d0daebc3 TG |
1930 | if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) |
1931 | if (ipv4_is_loopback(saddr)) | |
1932 | goto e_inval; | |
1933 | ||
f97c1e0c JP |
1934 | if (ipv4_is_zeronet(saddr)) { |
1935 | if (!ipv4_is_local_multicast(daddr)) | |
1da177e4 | 1936 | goto e_inval; |
b5f7e755 | 1937 | } else { |
9e56e380 DM |
1938 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, |
1939 | in_dev, &itag); | |
b5f7e755 ED |
1940 | if (err < 0) |
1941 | goto e_err; | |
1942 | } | |
4e7b2f14 | 1943 | rth = rt_dst_alloc(dev_net(dev)->loopback_dev, |
5c1e6aa3 | 1944 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); |
1da177e4 LT |
1945 | if (!rth) |
1946 | goto e_nobufs; | |
1947 | ||
cf911662 DM |
1948 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1949 | rth->dst.tclassid = itag; | |
1950 | #endif | |
d8d1f30b | 1951 | rth->dst.output = ip_rt_bug; |
1da177e4 | 1952 | |
5e2b61f7 | 1953 | rth->rt_key_dst = daddr; |
5e2b61f7 | 1954 | rth->rt_key_src = saddr; |
cf911662 DM |
1955 | rth->rt_genid = rt_genid(dev_net(dev)); |
1956 | rth->rt_flags = RTCF_MULTICAST; | |
1957 | rth->rt_type = RTN_MULTICAST; | |
475949d8 | 1958 | rth->rt_key_tos = tos; |
cf911662 | 1959 | rth->rt_dst = daddr; |
1da177e4 | 1960 | rth->rt_src = saddr; |
1b86a58f | 1961 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 1962 | rth->rt_iif = dev->ifindex; |
5e2b61f7 | 1963 | rth->rt_oif = 0; |
cf911662 | 1964 | rth->rt_mark = skb->mark; |
1da177e4 | 1965 | rth->rt_gateway = daddr; |
cf911662 | 1966 | rth->rt_peer_genid = 0; |
97bab73f | 1967 | rt_init_peer(rth, dev_net(dev)->ipv4.peers); |
cf911662 | 1968 | rth->fi = NULL; |
1da177e4 | 1969 | if (our) { |
d8d1f30b | 1970 | rth->dst.input= ip_local_deliver; |
1da177e4 LT |
1971 | rth->rt_flags |= RTCF_LOCAL; |
1972 | } | |
1973 | ||
1974 | #ifdef CONFIG_IP_MROUTE | |
f97c1e0c | 1975 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) |
d8d1f30b | 1976 | rth->dst.input = ip_mr_input; |
1da177e4 LT |
1977 | #endif |
1978 | RT_CACHE_STAT_INC(in_slow_mc); | |
1979 | ||
e84f84f2 | 1980 | hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev))); |
b23dd4fe | 1981 | rth = rt_intern_hash(hash, rth, skb, dev->ifindex); |
9aa3c94c | 1982 | return IS_ERR(rth) ? PTR_ERR(rth) : 0; |
1da177e4 LT |
1983 | |
1984 | e_nobufs: | |
1da177e4 | 1985 | return -ENOBUFS; |
1da177e4 | 1986 | e_inval: |
96d36220 | 1987 | return -EINVAL; |
b5f7e755 | 1988 | e_err: |
b5f7e755 | 1989 | return err; |
1da177e4 LT |
1990 | } |
1991 | ||
1992 | ||
1993 | static void ip_handle_martian_source(struct net_device *dev, | |
1994 | struct in_device *in_dev, | |
1995 | struct sk_buff *skb, | |
9e12bb22 AV |
1996 | __be32 daddr, |
1997 | __be32 saddr) | |
1da177e4 LT |
1998 | { |
1999 | RT_CACHE_STAT_INC(in_martian_src); | |
2000 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2001 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
2002 | /* | |
2003 | * RFC1812 recommendation, if source is martian, | |
2004 | * the only hint is MAC header. | |
2005 | */ | |
058bd4d2 | 2006 | pr_warn("martian source %pI4 from %pI4, on dev %s\n", |
673d57e7 | 2007 | &daddr, &saddr, dev->name); |
98e399f8 | 2008 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { |
058bd4d2 JP |
2009 | print_hex_dump(KERN_WARNING, "ll header: ", |
2010 | DUMP_PREFIX_OFFSET, 16, 1, | |
2011 | skb_mac_header(skb), | |
2012 | dev->hard_header_len, true); | |
1da177e4 LT |
2013 | } |
2014 | } | |
2015 | #endif | |
2016 | } | |
2017 | ||
47360228 | 2018 | /* called in rcu_read_lock() section */ |
5969f71d | 2019 | static int __mkroute_input(struct sk_buff *skb, |
982721f3 | 2020 | const struct fib_result *res, |
5969f71d SH |
2021 | struct in_device *in_dev, |
2022 | __be32 daddr, __be32 saddr, u32 tos, | |
2023 | struct rtable **result) | |
1da177e4 | 2024 | { |
1da177e4 LT |
2025 | struct rtable *rth; |
2026 | int err; | |
2027 | struct in_device *out_dev; | |
47360228 | 2028 | unsigned int flags = 0; |
d9c9df8c | 2029 | u32 itag; |
1da177e4 LT |
2030 | |
2031 | /* get a working reference to the output device */ | |
47360228 | 2032 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); |
1da177e4 | 2033 | if (out_dev == NULL) { |
e87cc472 | 2034 | net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n"); |
1da177e4 LT |
2035 | return -EINVAL; |
2036 | } | |
2037 | ||
2038 | ||
5c04c819 | 2039 | err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), |
9e56e380 | 2040 | in_dev->dev, in_dev, &itag); |
1da177e4 | 2041 | if (err < 0) { |
e905a9ed | 2042 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, |
1da177e4 | 2043 | saddr); |
e905a9ed | 2044 | |
1da177e4 LT |
2045 | goto cleanup; |
2046 | } | |
2047 | ||
2048 | if (err) | |
2049 | flags |= RTCF_DIRECTSRC; | |
2050 | ||
51b77cae | 2051 | if (out_dev == in_dev && err && |
1da177e4 LT |
2052 | (IN_DEV_SHARED_MEDIA(out_dev) || |
2053 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
2054 | flags |= RTCF_DOREDIRECT; | |
2055 | ||
2056 | if (skb->protocol != htons(ETH_P_IP)) { | |
2057 | /* Not IP (i.e. ARP). Do not create route, if it is | |
2058 | * invalid for proxy arp. DNAT routes are always valid. | |
65324144 JDB |
2059 | * |
2060 | * Proxy arp feature have been extended to allow, ARP | |
2061 | * replies back to the same interface, to support | |
2062 | * Private VLAN switch technologies. See arp.c. | |
1da177e4 | 2063 | */ |
65324144 JDB |
2064 | if (out_dev == in_dev && |
2065 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
1da177e4 LT |
2066 | err = -EINVAL; |
2067 | goto cleanup; | |
2068 | } | |
2069 | } | |
2070 | ||
5c1e6aa3 DM |
2071 | rth = rt_dst_alloc(out_dev->dev, |
2072 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2073 | IN_DEV_CONF_GET(out_dev, NOXFRM)); |
1da177e4 LT |
2074 | if (!rth) { |
2075 | err = -ENOBUFS; | |
2076 | goto cleanup; | |
2077 | } | |
2078 | ||
5e2b61f7 | 2079 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2080 | rth->rt_key_src = saddr; |
cf911662 DM |
2081 | rth->rt_genid = rt_genid(dev_net(rth->dst.dev)); |
2082 | rth->rt_flags = flags; | |
2083 | rth->rt_type = res->type; | |
475949d8 | 2084 | rth->rt_key_tos = tos; |
cf911662 | 2085 | rth->rt_dst = daddr; |
1da177e4 | 2086 | rth->rt_src = saddr; |
1b86a58f | 2087 | rth->rt_route_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2088 | rth->rt_iif = in_dev->dev->ifindex; |
5e2b61f7 | 2089 | rth->rt_oif = 0; |
cf911662 DM |
2090 | rth->rt_mark = skb->mark; |
2091 | rth->rt_gateway = daddr; | |
cf911662 | 2092 | rth->rt_peer_genid = 0; |
8b96d22d | 2093 | rt_init_peer(rth, &res->table->tb_peers); |
cf911662 | 2094 | rth->fi = NULL; |
1da177e4 | 2095 | |
d8d1f30b CG |
2096 | rth->dst.input = ip_forward; |
2097 | rth->dst.output = ip_output; | |
1da177e4 | 2098 | |
5e2b61f7 | 2099 | rt_set_nexthop(rth, NULL, res, res->fi, res->type, itag); |
1da177e4 | 2100 | |
1da177e4 LT |
2101 | *result = rth; |
2102 | err = 0; | |
2103 | cleanup: | |
1da177e4 | 2104 | return err; |
e905a9ed | 2105 | } |
1da177e4 | 2106 | |
5969f71d SH |
2107 | static int ip_mkroute_input(struct sk_buff *skb, |
2108 | struct fib_result *res, | |
68a5e3dd | 2109 | const struct flowi4 *fl4, |
5969f71d SH |
2110 | struct in_device *in_dev, |
2111 | __be32 daddr, __be32 saddr, u32 tos) | |
1da177e4 | 2112 | { |
5e73ea1a | 2113 | struct rtable *rth = NULL; |
1da177e4 | 2114 | int err; |
95c96174 | 2115 | unsigned int hash; |
1da177e4 LT |
2116 | |
2117 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
ff3fccb3 | 2118 | if (res->fi && res->fi->fib_nhs > 1) |
1b7fe593 | 2119 | fib_select_multipath(res); |
1da177e4 LT |
2120 | #endif |
2121 | ||
2122 | /* create a routing cache entry */ | |
2123 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth); | |
2124 | if (err) | |
2125 | return err; | |
1da177e4 LT |
2126 | |
2127 | /* put it into the cache */ | |
68a5e3dd | 2128 | hash = rt_hash(daddr, saddr, fl4->flowi4_iif, |
d8d1f30b | 2129 | rt_genid(dev_net(rth->dst.dev))); |
68a5e3dd | 2130 | rth = rt_intern_hash(hash, rth, skb, fl4->flowi4_iif); |
b23dd4fe DM |
2131 | if (IS_ERR(rth)) |
2132 | return PTR_ERR(rth); | |
2133 | return 0; | |
1da177e4 LT |
2134 | } |
2135 | ||
1da177e4 LT |
2136 | /* |
2137 | * NOTE. We drop all the packets that has local source | |
2138 | * addresses, because every properly looped back packet | |
2139 | * must have correct destination already attached by output routine. | |
2140 | * | |
2141 | * Such approach solves two big problems: | |
2142 | * 1. Not simplex devices are handled properly. | |
2143 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
ebc0ffae | 2144 | * called with rcu_read_lock() |
1da177e4 LT |
2145 | */ |
2146 | ||
9e12bb22 | 2147 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
c10237e0 | 2148 | u8 tos, struct net_device *dev) |
1da177e4 LT |
2149 | { |
2150 | struct fib_result res; | |
96d36220 | 2151 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
68a5e3dd | 2152 | struct flowi4 fl4; |
95c96174 | 2153 | unsigned int flags = 0; |
1da177e4 | 2154 | u32 itag = 0; |
95c96174 ED |
2155 | struct rtable *rth; |
2156 | unsigned int hash; | |
1da177e4 | 2157 | int err = -EINVAL; |
5e73ea1a | 2158 | struct net *net = dev_net(dev); |
1da177e4 LT |
2159 | |
2160 | /* IP on this device is disabled. */ | |
2161 | ||
2162 | if (!in_dev) | |
2163 | goto out; | |
2164 | ||
2165 | /* Check for the most weird martians, which can be not detected | |
2166 | by fib_lookup. | |
2167 | */ | |
2168 | ||
d0daebc3 | 2169 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) |
1da177e4 LT |
2170 | goto martian_source; |
2171 | ||
27a954bd | 2172 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) |
1da177e4 LT |
2173 | goto brd_input; |
2174 | ||
2175 | /* Accept zero addresses only to limited broadcast; | |
2176 | * I even do not know to fix it or not. Waiting for complains :-) | |
2177 | */ | |
f97c1e0c | 2178 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
2179 | goto martian_source; |
2180 | ||
d0daebc3 | 2181 | if (ipv4_is_zeronet(daddr)) |
1da177e4 LT |
2182 | goto martian_destination; |
2183 | ||
d0daebc3 TG |
2184 | if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) { |
2185 | if (ipv4_is_loopback(daddr)) | |
2186 | goto martian_destination; | |
2187 | ||
2188 | if (ipv4_is_loopback(saddr)) | |
2189 | goto martian_source; | |
2190 | } | |
2191 | ||
1da177e4 LT |
2192 | /* |
2193 | * Now we are ready to route packet. | |
2194 | */ | |
68a5e3dd DM |
2195 | fl4.flowi4_oif = 0; |
2196 | fl4.flowi4_iif = dev->ifindex; | |
2197 | fl4.flowi4_mark = skb->mark; | |
2198 | fl4.flowi4_tos = tos; | |
2199 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
2200 | fl4.daddr = daddr; | |
2201 | fl4.saddr = saddr; | |
2202 | err = fib_lookup(net, &fl4, &res); | |
251da413 | 2203 | if (err != 0) |
1da177e4 | 2204 | goto no_route; |
1da177e4 LT |
2205 | |
2206 | RT_CACHE_STAT_INC(in_slow_tot); | |
2207 | ||
2208 | if (res.type == RTN_BROADCAST) | |
2209 | goto brd_input; | |
2210 | ||
2211 | if (res.type == RTN_LOCAL) { | |
5c04c819 | 2212 | err = fib_validate_source(skb, saddr, daddr, tos, |
ebc0ffae | 2213 | net->loopback_dev->ifindex, |
9e56e380 | 2214 | dev, in_dev, &itag); |
b5f7e755 ED |
2215 | if (err < 0) |
2216 | goto martian_source_keep_err; | |
2217 | if (err) | |
1da177e4 | 2218 | flags |= RTCF_DIRECTSRC; |
1da177e4 LT |
2219 | goto local_input; |
2220 | } | |
2221 | ||
2222 | if (!IN_DEV_FORWARD(in_dev)) | |
251da413 | 2223 | goto no_route; |
1da177e4 LT |
2224 | if (res.type != RTN_UNICAST) |
2225 | goto martian_destination; | |
2226 | ||
68a5e3dd | 2227 | err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos); |
1da177e4 LT |
2228 | out: return err; |
2229 | ||
2230 | brd_input: | |
2231 | if (skb->protocol != htons(ETH_P_IP)) | |
2232 | goto e_inval; | |
2233 | ||
41347dcd | 2234 | if (!ipv4_is_zeronet(saddr)) { |
9e56e380 DM |
2235 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, |
2236 | in_dev, &itag); | |
1da177e4 | 2237 | if (err < 0) |
b5f7e755 | 2238 | goto martian_source_keep_err; |
1da177e4 LT |
2239 | if (err) |
2240 | flags |= RTCF_DIRECTSRC; | |
2241 | } | |
2242 | flags |= RTCF_BROADCAST; | |
2243 | res.type = RTN_BROADCAST; | |
2244 | RT_CACHE_STAT_INC(in_brd); | |
2245 | ||
2246 | local_input: | |
5c1e6aa3 DM |
2247 | rth = rt_dst_alloc(net->loopback_dev, |
2248 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false); | |
1da177e4 LT |
2249 | if (!rth) |
2250 | goto e_nobufs; | |
2251 | ||
cf911662 | 2252 | rth->dst.input= ip_local_deliver; |
d8d1f30b | 2253 | rth->dst.output= ip_rt_bug; |
cf911662 DM |
2254 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2255 | rth->dst.tclassid = itag; | |
2256 | #endif | |
1da177e4 | 2257 | |
5e2b61f7 | 2258 | rth->rt_key_dst = daddr; |
5e2b61f7 | 2259 | rth->rt_key_src = saddr; |
cf911662 DM |
2260 | rth->rt_genid = rt_genid(net); |
2261 | rth->rt_flags = flags|RTCF_LOCAL; | |
2262 | rth->rt_type = res.type; | |
475949d8 | 2263 | rth->rt_key_tos = tos; |
cf911662 | 2264 | rth->rt_dst = daddr; |
1da177e4 | 2265 | rth->rt_src = saddr; |
1b86a58f | 2266 | rth->rt_route_iif = dev->ifindex; |
5e2b61f7 | 2267 | rth->rt_iif = dev->ifindex; |
cf911662 DM |
2268 | rth->rt_oif = 0; |
2269 | rth->rt_mark = skb->mark; | |
1da177e4 | 2270 | rth->rt_gateway = daddr; |
cf911662 | 2271 | rth->rt_peer_genid = 0; |
97bab73f | 2272 | rt_init_peer(rth, net->ipv4.peers); |
cf911662 | 2273 | rth->fi = NULL; |
1da177e4 | 2274 | if (res.type == RTN_UNREACHABLE) { |
d8d1f30b CG |
2275 | rth->dst.input= ip_error; |
2276 | rth->dst.error= -err; | |
1da177e4 LT |
2277 | rth->rt_flags &= ~RTCF_LOCAL; |
2278 | } | |
68a5e3dd DM |
2279 | hash = rt_hash(daddr, saddr, fl4.flowi4_iif, rt_genid(net)); |
2280 | rth = rt_intern_hash(hash, rth, skb, fl4.flowi4_iif); | |
b23dd4fe DM |
2281 | err = 0; |
2282 | if (IS_ERR(rth)) | |
2283 | err = PTR_ERR(rth); | |
ebc0ffae | 2284 | goto out; |
1da177e4 LT |
2285 | |
2286 | no_route: | |
2287 | RT_CACHE_STAT_INC(in_no_route); | |
1da177e4 | 2288 | res.type = RTN_UNREACHABLE; |
7f53878d MC |
2289 | if (err == -ESRCH) |
2290 | err = -ENETUNREACH; | |
1da177e4 LT |
2291 | goto local_input; |
2292 | ||
2293 | /* | |
2294 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2295 | */ | |
2296 | martian_destination: | |
2297 | RT_CACHE_STAT_INC(in_martian_dst); | |
2298 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
e87cc472 JP |
2299 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
2300 | net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n", | |
2301 | &daddr, &saddr, dev->name); | |
1da177e4 | 2302 | #endif |
2c2910a4 | 2303 | |
1da177e4 LT |
2304 | e_inval: |
2305 | err = -EINVAL; | |
ebc0ffae | 2306 | goto out; |
1da177e4 LT |
2307 | |
2308 | e_nobufs: | |
2309 | err = -ENOBUFS; | |
ebc0ffae | 2310 | goto out; |
1da177e4 LT |
2311 | |
2312 | martian_source: | |
b5f7e755 ED |
2313 | err = -EINVAL; |
2314 | martian_source_keep_err: | |
1da177e4 | 2315 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); |
ebc0ffae | 2316 | goto out; |
1da177e4 LT |
2317 | } |
2318 | ||
407eadd9 | 2319 | int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
c10237e0 | 2320 | u8 tos, struct net_device *dev, bool noref) |
1da177e4 | 2321 | { |
95c96174 ED |
2322 | struct rtable *rth; |
2323 | unsigned int hash; | |
1da177e4 | 2324 | int iif = dev->ifindex; |
b5921910 | 2325 | struct net *net; |
96d36220 | 2326 | int res; |
1da177e4 | 2327 | |
c346dca1 | 2328 | net = dev_net(dev); |
1080d709 | 2329 | |
96d36220 ED |
2330 | rcu_read_lock(); |
2331 | ||
1080d709 NH |
2332 | if (!rt_caching(net)) |
2333 | goto skip_cache; | |
2334 | ||
1da177e4 | 2335 | tos &= IPTOS_RT_MASK; |
e84f84f2 | 2336 | hash = rt_hash(daddr, saddr, iif, rt_genid(net)); |
1da177e4 | 2337 | |
1da177e4 | 2338 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2339 | rth = rcu_dereference(rth->dst.rt_next)) { |
5e2b61f7 DM |
2340 | if ((((__force u32)rth->rt_key_dst ^ (__force u32)daddr) | |
2341 | ((__force u32)rth->rt_key_src ^ (__force u32)saddr) | | |
97a80410 | 2342 | (rth->rt_route_iif ^ iif) | |
475949d8 | 2343 | (rth->rt_key_tos ^ tos)) == 0 && |
5e2b61f7 | 2344 | rth->rt_mark == skb->mark && |
d8d1f30b | 2345 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2346 | !rt_is_expired(rth)) { |
de398fb8 | 2347 | ipv4_validate_peer(rth); |
407eadd9 | 2348 | if (noref) { |
d8d1f30b CG |
2349 | dst_use_noref(&rth->dst, jiffies); |
2350 | skb_dst_set_noref(skb, &rth->dst); | |
407eadd9 | 2351 | } else { |
d8d1f30b CG |
2352 | dst_use(&rth->dst, jiffies); |
2353 | skb_dst_set(skb, &rth->dst); | |
407eadd9 | 2354 | } |
1da177e4 LT |
2355 | RT_CACHE_STAT_INC(in_hit); |
2356 | rcu_read_unlock(); | |
1da177e4 LT |
2357 | return 0; |
2358 | } | |
2359 | RT_CACHE_STAT_INC(in_hlist_search); | |
2360 | } | |
1da177e4 | 2361 | |
1080d709 | 2362 | skip_cache: |
1da177e4 LT |
2363 | /* Multicast recognition logic is moved from route cache to here. |
2364 | The problem was that too many Ethernet cards have broken/missing | |
2365 | hardware multicast filters :-( As result the host on multicasting | |
2366 | network acquires a lot of useless route cache entries, sort of | |
2367 | SDR messages from all the world. Now we try to get rid of them. | |
2368 | Really, provided software IP multicast filter is organized | |
2369 | reasonably (at least, hashed), it does not result in a slowdown | |
2370 | comparing with route cache reject entries. | |
2371 | Note, that multicast routers are not affected, because | |
2372 | route cache entry is created eventually. | |
2373 | */ | |
f97c1e0c | 2374 | if (ipv4_is_multicast(daddr)) { |
96d36220 | 2375 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 2376 | |
96d36220 | 2377 | if (in_dev) { |
dbdd9a52 DM |
2378 | int our = ip_check_mc_rcu(in_dev, daddr, saddr, |
2379 | ip_hdr(skb)->protocol); | |
1da177e4 LT |
2380 | if (our |
2381 | #ifdef CONFIG_IP_MROUTE | |
9d4fb27d JP |
2382 | || |
2383 | (!ipv4_is_local_multicast(daddr) && | |
2384 | IN_DEV_MFORWARD(in_dev)) | |
1da177e4 | 2385 | #endif |
9d4fb27d | 2386 | ) { |
96d36220 ED |
2387 | int res = ip_route_input_mc(skb, daddr, saddr, |
2388 | tos, dev, our); | |
1da177e4 | 2389 | rcu_read_unlock(); |
96d36220 | 2390 | return res; |
1da177e4 LT |
2391 | } |
2392 | } | |
2393 | rcu_read_unlock(); | |
2394 | return -EINVAL; | |
2395 | } | |
c10237e0 | 2396 | res = ip_route_input_slow(skb, daddr, saddr, tos, dev); |
96d36220 ED |
2397 | rcu_read_unlock(); |
2398 | return res; | |
1da177e4 | 2399 | } |
407eadd9 | 2400 | EXPORT_SYMBOL(ip_route_input_common); |
1da177e4 | 2401 | |
ebc0ffae | 2402 | /* called with rcu_read_lock() */ |
982721f3 | 2403 | static struct rtable *__mkroute_output(const struct fib_result *res, |
68a5e3dd | 2404 | const struct flowi4 *fl4, |
813b3b5d | 2405 | __be32 orig_daddr, __be32 orig_saddr, |
f61759e6 JA |
2406 | int orig_oif, __u8 orig_rtos, |
2407 | struct net_device *dev_out, | |
5ada5527 | 2408 | unsigned int flags) |
1da177e4 | 2409 | { |
982721f3 | 2410 | struct fib_info *fi = res->fi; |
5ada5527 | 2411 | struct in_device *in_dev; |
982721f3 | 2412 | u16 type = res->type; |
5ada5527 | 2413 | struct rtable *rth; |
1da177e4 | 2414 | |
d0daebc3 TG |
2415 | in_dev = __in_dev_get_rcu(dev_out); |
2416 | if (!in_dev) | |
5ada5527 | 2417 | return ERR_PTR(-EINVAL); |
1da177e4 | 2418 | |
d0daebc3 TG |
2419 | if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) |
2420 | if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) | |
2421 | return ERR_PTR(-EINVAL); | |
2422 | ||
68a5e3dd | 2423 | if (ipv4_is_lbcast(fl4->daddr)) |
982721f3 | 2424 | type = RTN_BROADCAST; |
68a5e3dd | 2425 | else if (ipv4_is_multicast(fl4->daddr)) |
982721f3 | 2426 | type = RTN_MULTICAST; |
68a5e3dd | 2427 | else if (ipv4_is_zeronet(fl4->daddr)) |
5ada5527 | 2428 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
2429 | |
2430 | if (dev_out->flags & IFF_LOOPBACK) | |
2431 | flags |= RTCF_LOCAL; | |
2432 | ||
982721f3 | 2433 | if (type == RTN_BROADCAST) { |
1da177e4 | 2434 | flags |= RTCF_BROADCAST | RTCF_LOCAL; |
982721f3 DM |
2435 | fi = NULL; |
2436 | } else if (type == RTN_MULTICAST) { | |
dd28d1a0 | 2437 | flags |= RTCF_MULTICAST | RTCF_LOCAL; |
813b3b5d DM |
2438 | if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, |
2439 | fl4->flowi4_proto)) | |
1da177e4 LT |
2440 | flags &= ~RTCF_LOCAL; |
2441 | /* If multicast route do not exist use | |
dd28d1a0 ED |
2442 | * default one, but do not gateway in this case. |
2443 | * Yes, it is hack. | |
1da177e4 | 2444 | */ |
982721f3 DM |
2445 | if (fi && res->prefixlen < 4) |
2446 | fi = NULL; | |
1da177e4 LT |
2447 | } |
2448 | ||
5c1e6aa3 DM |
2449 | rth = rt_dst_alloc(dev_out, |
2450 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
0c4dcd58 | 2451 | IN_DEV_CONF_GET(in_dev, NOXFRM)); |
8391d07b | 2452 | if (!rth) |
5ada5527 | 2453 | return ERR_PTR(-ENOBUFS); |
8391d07b | 2454 | |
cf911662 DM |
2455 | rth->dst.output = ip_output; |
2456 | ||
813b3b5d DM |
2457 | rth->rt_key_dst = orig_daddr; |
2458 | rth->rt_key_src = orig_saddr; | |
cf911662 DM |
2459 | rth->rt_genid = rt_genid(dev_net(dev_out)); |
2460 | rth->rt_flags = flags; | |
2461 | rth->rt_type = type; | |
f61759e6 | 2462 | rth->rt_key_tos = orig_rtos; |
68a5e3dd DM |
2463 | rth->rt_dst = fl4->daddr; |
2464 | rth->rt_src = fl4->saddr; | |
1b86a58f | 2465 | rth->rt_route_iif = 0; |
813b3b5d DM |
2466 | rth->rt_iif = orig_oif ? : dev_out->ifindex; |
2467 | rth->rt_oif = orig_oif; | |
2468 | rth->rt_mark = fl4->flowi4_mark; | |
68a5e3dd | 2469 | rth->rt_gateway = fl4->daddr; |
cf911662 | 2470 | rth->rt_peer_genid = 0; |
8b96d22d DM |
2471 | rt_init_peer(rth, (res->table ? |
2472 | &res->table->tb_peers : | |
2473 | dev_net(dev_out)->ipv4.peers)); | |
cf911662 | 2474 | rth->fi = NULL; |
1da177e4 LT |
2475 | |
2476 | RT_CACHE_STAT_INC(out_slow_tot); | |
2477 | ||
41347dcd | 2478 | if (flags & RTCF_LOCAL) |
d8d1f30b | 2479 | rth->dst.input = ip_local_deliver; |
1da177e4 | 2480 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
e905a9ed | 2481 | if (flags & RTCF_LOCAL && |
1da177e4 | 2482 | !(dev_out->flags & IFF_LOOPBACK)) { |
d8d1f30b | 2483 | rth->dst.output = ip_mc_output; |
1da177e4 LT |
2484 | RT_CACHE_STAT_INC(out_slow_mc); |
2485 | } | |
2486 | #ifdef CONFIG_IP_MROUTE | |
982721f3 | 2487 | if (type == RTN_MULTICAST) { |
1da177e4 | 2488 | if (IN_DEV_MFORWARD(in_dev) && |
813b3b5d | 2489 | !ipv4_is_local_multicast(fl4->daddr)) { |
d8d1f30b CG |
2490 | rth->dst.input = ip_mr_input; |
2491 | rth->dst.output = ip_mc_output; | |
1da177e4 LT |
2492 | } |
2493 | } | |
2494 | #endif | |
2495 | } | |
2496 | ||
813b3b5d | 2497 | rt_set_nexthop(rth, fl4, res, fi, type, 0); |
1da177e4 | 2498 | |
7586eceb ED |
2499 | if (fl4->flowi4_flags & FLOWI_FLAG_RT_NOCACHE) |
2500 | rth->dst.flags |= DST_NOCACHE; | |
2501 | ||
5ada5527 | 2502 | return rth; |
1da177e4 LT |
2503 | } |
2504 | ||
1da177e4 LT |
2505 | /* |
2506 | * Major route resolver routine. | |
0197aa38 | 2507 | * called with rcu_read_lock(); |
1da177e4 LT |
2508 | */ |
2509 | ||
813b3b5d | 2510 | static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4) |
1da177e4 | 2511 | { |
1da177e4 | 2512 | struct net_device *dev_out = NULL; |
f61759e6 | 2513 | __u8 tos = RT_FL_TOS(fl4); |
813b3b5d DM |
2514 | unsigned int flags = 0; |
2515 | struct fib_result res; | |
5ada5527 | 2516 | struct rtable *rth; |
813b3b5d DM |
2517 | __be32 orig_daddr; |
2518 | __be32 orig_saddr; | |
2519 | int orig_oif; | |
1da177e4 LT |
2520 | |
2521 | res.fi = NULL; | |
8b96d22d | 2522 | res.table = NULL; |
1da177e4 LT |
2523 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
2524 | res.r = NULL; | |
2525 | #endif | |
2526 | ||
813b3b5d DM |
2527 | orig_daddr = fl4->daddr; |
2528 | orig_saddr = fl4->saddr; | |
2529 | orig_oif = fl4->flowi4_oif; | |
2530 | ||
2531 | fl4->flowi4_iif = net->loopback_dev->ifindex; | |
2532 | fl4->flowi4_tos = tos & IPTOS_RT_MASK; | |
2533 | fl4->flowi4_scope = ((tos & RTO_ONLINK) ? | |
2534 | RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); | |
44713b67 | 2535 | |
010c2708 | 2536 | rcu_read_lock(); |
813b3b5d | 2537 | if (fl4->saddr) { |
b23dd4fe | 2538 | rth = ERR_PTR(-EINVAL); |
813b3b5d DM |
2539 | if (ipv4_is_multicast(fl4->saddr) || |
2540 | ipv4_is_lbcast(fl4->saddr) || | |
2541 | ipv4_is_zeronet(fl4->saddr)) | |
1da177e4 LT |
2542 | goto out; |
2543 | ||
1da177e4 LT |
2544 | /* I removed check for oif == dev_out->oif here. |
2545 | It was wrong for two reasons: | |
1ab35276 DL |
2546 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr |
2547 | is assigned to multiple interfaces. | |
1da177e4 LT |
2548 | 2. Moreover, we are allowed to send packets with saddr |
2549 | of another iface. --ANK | |
2550 | */ | |
2551 | ||
813b3b5d DM |
2552 | if (fl4->flowi4_oif == 0 && |
2553 | (ipv4_is_multicast(fl4->daddr) || | |
2554 | ipv4_is_lbcast(fl4->daddr))) { | |
a210d01a | 2555 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2556 | dev_out = __ip_dev_find(net, fl4->saddr, false); |
a210d01a JA |
2557 | if (dev_out == NULL) |
2558 | goto out; | |
2559 | ||
1da177e4 LT |
2560 | /* Special hack: user can direct multicasts |
2561 | and limited broadcast via necessary interface | |
2562 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2563 | This hack is not just for fun, it allows | |
2564 | vic,vat and friends to work. | |
2565 | They bind socket to loopback, set ttl to zero | |
2566 | and expect that it will work. | |
2567 | From the viewpoint of routing cache they are broken, | |
2568 | because we are not allowed to build multicast path | |
2569 | with loopback source addr (look, routing cache | |
2570 | cannot know, that ttl is zero, so that packet | |
2571 | will not leave this host and route is valid). | |
2572 | Luckily, this hack is good workaround. | |
2573 | */ | |
2574 | ||
813b3b5d | 2575 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2576 | goto make_route; |
2577 | } | |
a210d01a | 2578 | |
813b3b5d | 2579 | if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { |
a210d01a | 2580 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2581 | if (!__ip_dev_find(net, fl4->saddr, false)) |
a210d01a | 2582 | goto out; |
a210d01a | 2583 | } |
1da177e4 LT |
2584 | } |
2585 | ||
2586 | ||
813b3b5d DM |
2587 | if (fl4->flowi4_oif) { |
2588 | dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); | |
b23dd4fe | 2589 | rth = ERR_PTR(-ENODEV); |
1da177e4 LT |
2590 | if (dev_out == NULL) |
2591 | goto out; | |
e5ed6399 HX |
2592 | |
2593 | /* RACE: Check return value of inet_select_addr instead. */ | |
fc75fc83 | 2594 | if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { |
b23dd4fe | 2595 | rth = ERR_PTR(-ENETUNREACH); |
fc75fc83 ED |
2596 | goto out; |
2597 | } | |
813b3b5d DM |
2598 | if (ipv4_is_local_multicast(fl4->daddr) || |
2599 | ipv4_is_lbcast(fl4->daddr)) { | |
2600 | if (!fl4->saddr) | |
2601 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2602 | RT_SCOPE_LINK); | |
1da177e4 LT |
2603 | goto make_route; |
2604 | } | |
813b3b5d DM |
2605 | if (fl4->saddr) { |
2606 | if (ipv4_is_multicast(fl4->daddr)) | |
2607 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2608 | fl4->flowi4_scope); | |
2609 | else if (!fl4->daddr) | |
2610 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2611 | RT_SCOPE_HOST); | |
1da177e4 LT |
2612 | } |
2613 | } | |
2614 | ||
813b3b5d DM |
2615 | if (!fl4->daddr) { |
2616 | fl4->daddr = fl4->saddr; | |
2617 | if (!fl4->daddr) | |
2618 | fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); | |
b40afd0e | 2619 | dev_out = net->loopback_dev; |
813b3b5d | 2620 | fl4->flowi4_oif = net->loopback_dev->ifindex; |
1da177e4 LT |
2621 | res.type = RTN_LOCAL; |
2622 | flags |= RTCF_LOCAL; | |
2623 | goto make_route; | |
2624 | } | |
2625 | ||
813b3b5d | 2626 | if (fib_lookup(net, fl4, &res)) { |
1da177e4 | 2627 | res.fi = NULL; |
8b96d22d | 2628 | res.table = NULL; |
813b3b5d | 2629 | if (fl4->flowi4_oif) { |
1da177e4 LT |
2630 | /* Apparently, routing tables are wrong. Assume, |
2631 | that the destination is on link. | |
2632 | ||
2633 | WHY? DW. | |
2634 | Because we are allowed to send to iface | |
2635 | even if it has NO routes and NO assigned | |
2636 | addresses. When oif is specified, routing | |
2637 | tables are looked up with only one purpose: | |
2638 | to catch if destination is gatewayed, rather than | |
2639 | direct. Moreover, if MSG_DONTROUTE is set, | |
2640 | we send packet, ignoring both routing tables | |
2641 | and ifaddr state. --ANK | |
2642 | ||
2643 | ||
2644 | We could make it even if oif is unknown, | |
2645 | likely IPv6, but we do not. | |
2646 | */ | |
2647 | ||
813b3b5d DM |
2648 | if (fl4->saddr == 0) |
2649 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2650 | RT_SCOPE_LINK); | |
1da177e4 LT |
2651 | res.type = RTN_UNICAST; |
2652 | goto make_route; | |
2653 | } | |
b23dd4fe | 2654 | rth = ERR_PTR(-ENETUNREACH); |
1da177e4 LT |
2655 | goto out; |
2656 | } | |
1da177e4 LT |
2657 | |
2658 | if (res.type == RTN_LOCAL) { | |
813b3b5d | 2659 | if (!fl4->saddr) { |
9fc3bbb4 | 2660 | if (res.fi->fib_prefsrc) |
813b3b5d | 2661 | fl4->saddr = res.fi->fib_prefsrc; |
9fc3bbb4 | 2662 | else |
813b3b5d | 2663 | fl4->saddr = fl4->daddr; |
9fc3bbb4 | 2664 | } |
b40afd0e | 2665 | dev_out = net->loopback_dev; |
813b3b5d | 2666 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2667 | res.fi = NULL; |
2668 | flags |= RTCF_LOCAL; | |
2669 | goto make_route; | |
2670 | } | |
2671 | ||
2672 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
813b3b5d | 2673 | if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0) |
1b7fe593 | 2674 | fib_select_multipath(&res); |
1da177e4 LT |
2675 | else |
2676 | #endif | |
21d8c49e DM |
2677 | if (!res.prefixlen && |
2678 | res.table->tb_num_default > 1 && | |
813b3b5d | 2679 | res.type == RTN_UNICAST && !fl4->flowi4_oif) |
0c838ff1 | 2680 | fib_select_default(&res); |
1da177e4 | 2681 | |
813b3b5d DM |
2682 | if (!fl4->saddr) |
2683 | fl4->saddr = FIB_RES_PREFSRC(net, res); | |
1da177e4 | 2684 | |
1da177e4 | 2685 | dev_out = FIB_RES_DEV(res); |
813b3b5d | 2686 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2687 | |
2688 | ||
2689 | make_route: | |
813b3b5d | 2690 | rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif, |
f61759e6 | 2691 | tos, dev_out, flags); |
b23dd4fe | 2692 | if (!IS_ERR(rth)) { |
5ada5527 DM |
2693 | unsigned int hash; |
2694 | ||
813b3b5d | 2695 | hash = rt_hash(orig_daddr, orig_saddr, orig_oif, |
5ada5527 | 2696 | rt_genid(dev_net(dev_out))); |
813b3b5d | 2697 | rth = rt_intern_hash(hash, rth, NULL, orig_oif); |
5ada5527 | 2698 | } |
1da177e4 | 2699 | |
010c2708 DM |
2700 | out: |
2701 | rcu_read_unlock(); | |
b23dd4fe | 2702 | return rth; |
1da177e4 LT |
2703 | } |
2704 | ||
813b3b5d | 2705 | struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4) |
1da177e4 | 2706 | { |
1da177e4 | 2707 | struct rtable *rth; |
010c2708 | 2708 | unsigned int hash; |
1da177e4 | 2709 | |
1080d709 NH |
2710 | if (!rt_caching(net)) |
2711 | goto slow_output; | |
2712 | ||
9d6ec938 | 2713 | hash = rt_hash(flp4->daddr, flp4->saddr, flp4->flowi4_oif, rt_genid(net)); |
1da177e4 LT |
2714 | |
2715 | rcu_read_lock_bh(); | |
a898def2 | 2716 | for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth; |
d8d1f30b | 2717 | rth = rcu_dereference_bh(rth->dst.rt_next)) { |
9d6ec938 DM |
2718 | if (rth->rt_key_dst == flp4->daddr && |
2719 | rth->rt_key_src == flp4->saddr && | |
c7537967 | 2720 | rt_is_output_route(rth) && |
9d6ec938 DM |
2721 | rth->rt_oif == flp4->flowi4_oif && |
2722 | rth->rt_mark == flp4->flowi4_mark && | |
475949d8 | 2723 | !((rth->rt_key_tos ^ flp4->flowi4_tos) & |
b5921910 | 2724 | (IPTOS_RT_MASK | RTO_ONLINK)) && |
d8d1f30b | 2725 | net_eq(dev_net(rth->dst.dev), net) && |
e84f84f2 | 2726 | !rt_is_expired(rth)) { |
de398fb8 | 2727 | ipv4_validate_peer(rth); |
d8d1f30b | 2728 | dst_use(&rth->dst, jiffies); |
1da177e4 LT |
2729 | RT_CACHE_STAT_INC(out_hit); |
2730 | rcu_read_unlock_bh(); | |
56157872 DM |
2731 | if (!flp4->saddr) |
2732 | flp4->saddr = rth->rt_src; | |
2733 | if (!flp4->daddr) | |
2734 | flp4->daddr = rth->rt_dst; | |
b23dd4fe | 2735 | return rth; |
1da177e4 LT |
2736 | } |
2737 | RT_CACHE_STAT_INC(out_hlist_search); | |
2738 | } | |
2739 | rcu_read_unlock_bh(); | |
2740 | ||
1080d709 | 2741 | slow_output: |
9d6ec938 | 2742 | return ip_route_output_slow(net, flp4); |
1da177e4 | 2743 | } |
d8c97a94 ACM |
2744 | EXPORT_SYMBOL_GPL(__ip_route_output_key); |
2745 | ||
ae2688d5 JW |
2746 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) |
2747 | { | |
2748 | return NULL; | |
2749 | } | |
2750 | ||
ebb762f2 | 2751 | static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst) |
ec831ea7 | 2752 | { |
618f9bc7 SK |
2753 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
2754 | ||
2755 | return mtu ? : dst->dev->mtu; | |
ec831ea7 RD |
2756 | } |
2757 | ||
14e50e57 DM |
2758 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) |
2759 | { | |
2760 | } | |
2761 | ||
0972ddb2 HB |
2762 | static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, |
2763 | unsigned long old) | |
2764 | { | |
2765 | return NULL; | |
2766 | } | |
2767 | ||
14e50e57 DM |
2768 | static struct dst_ops ipv4_dst_blackhole_ops = { |
2769 | .family = AF_INET, | |
09640e63 | 2770 | .protocol = cpu_to_be16(ETH_P_IP), |
14e50e57 | 2771 | .destroy = ipv4_dst_destroy, |
ae2688d5 | 2772 | .check = ipv4_blackhole_dst_check, |
ebb762f2 | 2773 | .mtu = ipv4_blackhole_mtu, |
214f45c9 | 2774 | .default_advmss = ipv4_default_advmss, |
14e50e57 | 2775 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, |
0972ddb2 | 2776 | .cow_metrics = ipv4_rt_blackhole_cow_metrics, |
d3aaeb38 | 2777 | .neigh_lookup = ipv4_neigh_lookup, |
14e50e57 DM |
2778 | }; |
2779 | ||
2774c131 | 2780 | struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) |
14e50e57 | 2781 | { |
5c1e6aa3 | 2782 | struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, 0, 0); |
2774c131 | 2783 | struct rtable *ort = (struct rtable *) dst_orig; |
14e50e57 DM |
2784 | |
2785 | if (rt) { | |
d8d1f30b | 2786 | struct dst_entry *new = &rt->dst; |
14e50e57 | 2787 | |
14e50e57 | 2788 | new->__use = 1; |
352e512c HX |
2789 | new->input = dst_discard; |
2790 | new->output = dst_discard; | |
defb3519 | 2791 | dst_copy_metrics(new, &ort->dst); |
14e50e57 | 2792 | |
d8d1f30b | 2793 | new->dev = ort->dst.dev; |
14e50e57 DM |
2794 | if (new->dev) |
2795 | dev_hold(new->dev); | |
2796 | ||
5e2b61f7 DM |
2797 | rt->rt_key_dst = ort->rt_key_dst; |
2798 | rt->rt_key_src = ort->rt_key_src; | |
475949d8 | 2799 | rt->rt_key_tos = ort->rt_key_tos; |
1b86a58f | 2800 | rt->rt_route_iif = ort->rt_route_iif; |
5e2b61f7 DM |
2801 | rt->rt_iif = ort->rt_iif; |
2802 | rt->rt_oif = ort->rt_oif; | |
2803 | rt->rt_mark = ort->rt_mark; | |
14e50e57 | 2804 | |
e84f84f2 | 2805 | rt->rt_genid = rt_genid(net); |
14e50e57 DM |
2806 | rt->rt_flags = ort->rt_flags; |
2807 | rt->rt_type = ort->rt_type; | |
2808 | rt->rt_dst = ort->rt_dst; | |
2809 | rt->rt_src = ort->rt_src; | |
14e50e57 | 2810 | rt->rt_gateway = ort->rt_gateway; |
97bab73f | 2811 | rt_transfer_peer(rt, ort); |
62fa8a84 DM |
2812 | rt->fi = ort->fi; |
2813 | if (rt->fi) | |
2814 | atomic_inc(&rt->fi->fib_clntref); | |
14e50e57 DM |
2815 | |
2816 | dst_free(new); | |
2817 | } | |
2818 | ||
2774c131 DM |
2819 | dst_release(dst_orig); |
2820 | ||
2821 | return rt ? &rt->dst : ERR_PTR(-ENOMEM); | |
14e50e57 DM |
2822 | } |
2823 | ||
9d6ec938 | 2824 | struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, |
b23dd4fe | 2825 | struct sock *sk) |
1da177e4 | 2826 | { |
9d6ec938 | 2827 | struct rtable *rt = __ip_route_output_key(net, flp4); |
1da177e4 | 2828 | |
b23dd4fe DM |
2829 | if (IS_ERR(rt)) |
2830 | return rt; | |
1da177e4 | 2831 | |
56157872 | 2832 | if (flp4->flowi4_proto) |
9d6ec938 DM |
2833 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
2834 | flowi4_to_flowi(flp4), | |
2835 | sk, 0); | |
1da177e4 | 2836 | |
b23dd4fe | 2837 | return rt; |
1da177e4 | 2838 | } |
d8c97a94 ACM |
2839 | EXPORT_SYMBOL_GPL(ip_route_output_flow); |
2840 | ||
4feb88e5 BT |
2841 | static int rt_fill_info(struct net *net, |
2842 | struct sk_buff *skb, u32 pid, u32 seq, int event, | |
b6544c0b | 2843 | int nowait, unsigned int flags) |
1da177e4 | 2844 | { |
511c3f92 | 2845 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 2846 | struct rtmsg *r; |
be403ea1 | 2847 | struct nlmsghdr *nlh; |
2bc8ca40 | 2848 | unsigned long expires = 0; |
81166dd6 | 2849 | u32 id = 0, error; |
be403ea1 TG |
2850 | |
2851 | nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags); | |
2852 | if (nlh == NULL) | |
26932566 | 2853 | return -EMSGSIZE; |
be403ea1 TG |
2854 | |
2855 | r = nlmsg_data(nlh); | |
1da177e4 LT |
2856 | r->rtm_family = AF_INET; |
2857 | r->rtm_dst_len = 32; | |
2858 | r->rtm_src_len = 0; | |
475949d8 | 2859 | r->rtm_tos = rt->rt_key_tos; |
1da177e4 | 2860 | r->rtm_table = RT_TABLE_MAIN; |
f3756b79 DM |
2861 | if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN)) |
2862 | goto nla_put_failure; | |
1da177e4 LT |
2863 | r->rtm_type = rt->rt_type; |
2864 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2865 | r->rtm_protocol = RTPROT_UNSPEC; | |
2866 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2867 | if (rt->rt_flags & RTCF_NOTIFY) | |
2868 | r->rtm_flags |= RTM_F_NOTIFY; | |
be403ea1 | 2869 | |
f3756b79 DM |
2870 | if (nla_put_be32(skb, RTA_DST, rt->rt_dst)) |
2871 | goto nla_put_failure; | |
5e2b61f7 | 2872 | if (rt->rt_key_src) { |
1da177e4 | 2873 | r->rtm_src_len = 32; |
f3756b79 DM |
2874 | if (nla_put_be32(skb, RTA_SRC, rt->rt_key_src)) |
2875 | goto nla_put_failure; | |
1da177e4 | 2876 | } |
f3756b79 DM |
2877 | if (rt->dst.dev && |
2878 | nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) | |
2879 | goto nla_put_failure; | |
c7066f70 | 2880 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
2881 | if (rt->dst.tclassid && |
2882 | nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid)) | |
2883 | goto nla_put_failure; | |
1da177e4 | 2884 | #endif |
41347dcd DM |
2885 | if (!rt_is_input_route(rt) && |
2886 | rt->rt_src != rt->rt_key_src) { | |
f3756b79 DM |
2887 | if (nla_put_be32(skb, RTA_PREFSRC, rt->rt_src)) |
2888 | goto nla_put_failure; | |
2889 | } | |
2890 | if (rt->rt_dst != rt->rt_gateway && | |
2891 | nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway)) | |
2892 | goto nla_put_failure; | |
be403ea1 | 2893 | |
defb3519 | 2894 | if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) |
be403ea1 TG |
2895 | goto nla_put_failure; |
2896 | ||
f3756b79 DM |
2897 | if (rt->rt_mark && |
2898 | nla_put_be32(skb, RTA_MARK, rt->rt_mark)) | |
2899 | goto nla_put_failure; | |
963bfeee | 2900 | |
d8d1f30b | 2901 | error = rt->dst.error; |
97bab73f DM |
2902 | if (rt_has_peer(rt)) { |
2903 | const struct inet_peer *peer = rt_peer_ptr(rt); | |
2904 | inet_peer_refcheck(peer); | |
fe6fe792 | 2905 | id = atomic_read(&peer->ip_id_count) & 0xffff; |
fe6fe792 | 2906 | expires = ACCESS_ONCE(peer->pmtu_expires); |
2bc8ca40 SK |
2907 | if (expires) { |
2908 | if (time_before(jiffies, expires)) | |
2909 | expires -= jiffies; | |
2910 | else | |
2911 | expires = 0; | |
2912 | } | |
1da177e4 | 2913 | } |
be403ea1 | 2914 | |
c7537967 | 2915 | if (rt_is_input_route(rt)) { |
1da177e4 | 2916 | #ifdef CONFIG_IP_MROUTE |
e448515c | 2917 | __be32 dst = rt->rt_dst; |
1da177e4 | 2918 | |
f97c1e0c | 2919 | if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) && |
4feb88e5 | 2920 | IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { |
9a1b9496 DM |
2921 | int err = ipmr_get_route(net, skb, |
2922 | rt->rt_src, rt->rt_dst, | |
2923 | r, nowait); | |
1da177e4 LT |
2924 | if (err <= 0) { |
2925 | if (!nowait) { | |
2926 | if (err == 0) | |
2927 | return 0; | |
be403ea1 | 2928 | goto nla_put_failure; |
1da177e4 LT |
2929 | } else { |
2930 | if (err == -EMSGSIZE) | |
be403ea1 | 2931 | goto nla_put_failure; |
e3703b3d | 2932 | error = err; |
1da177e4 LT |
2933 | } |
2934 | } | |
2935 | } else | |
2936 | #endif | |
f3756b79 DM |
2937 | if (nla_put_u32(skb, RTA_IIF, rt->rt_iif)) |
2938 | goto nla_put_failure; | |
1da177e4 LT |
2939 | } |
2940 | ||
81166dd6 | 2941 | if (rtnl_put_cacheinfo(skb, &rt->dst, id, 0, 0, |
e3703b3d TG |
2942 | expires, error) < 0) |
2943 | goto nla_put_failure; | |
be403ea1 TG |
2944 | |
2945 | return nlmsg_end(skb, nlh); | |
1da177e4 | 2946 | |
be403ea1 | 2947 | nla_put_failure: |
26932566 PM |
2948 | nlmsg_cancel(skb, nlh); |
2949 | return -EMSGSIZE; | |
1da177e4 LT |
2950 | } |
2951 | ||
5e73ea1a | 2952 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg) |
1da177e4 | 2953 | { |
3b1e0a65 | 2954 | struct net *net = sock_net(in_skb->sk); |
d889ce3b TG |
2955 | struct rtmsg *rtm; |
2956 | struct nlattr *tb[RTA_MAX+1]; | |
1da177e4 | 2957 | struct rtable *rt = NULL; |
9e12bb22 AV |
2958 | __be32 dst = 0; |
2959 | __be32 src = 0; | |
2960 | u32 iif; | |
d889ce3b | 2961 | int err; |
963bfeee | 2962 | int mark; |
1da177e4 LT |
2963 | struct sk_buff *skb; |
2964 | ||
d889ce3b TG |
2965 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); |
2966 | if (err < 0) | |
2967 | goto errout; | |
2968 | ||
2969 | rtm = nlmsg_data(nlh); | |
2970 | ||
1da177e4 | 2971 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
d889ce3b TG |
2972 | if (skb == NULL) { |
2973 | err = -ENOBUFS; | |
2974 | goto errout; | |
2975 | } | |
1da177e4 LT |
2976 | |
2977 | /* Reserve room for dummy headers, this skb can pass | |
2978 | through good chunk of routing engine. | |
2979 | */ | |
459a98ed | 2980 | skb_reset_mac_header(skb); |
c1d2bbe1 | 2981 | skb_reset_network_header(skb); |
d2c962b8 SH |
2982 | |
2983 | /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ | |
eddc9ec5 | 2984 | ip_hdr(skb)->protocol = IPPROTO_ICMP; |
1da177e4 LT |
2985 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); |
2986 | ||
17fb2c64 AV |
2987 | src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0; |
2988 | dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; | |
d889ce3b | 2989 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; |
963bfeee | 2990 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; |
1da177e4 LT |
2991 | |
2992 | if (iif) { | |
d889ce3b TG |
2993 | struct net_device *dev; |
2994 | ||
1937504d | 2995 | dev = __dev_get_by_index(net, iif); |
d889ce3b TG |
2996 | if (dev == NULL) { |
2997 | err = -ENODEV; | |
2998 | goto errout_free; | |
2999 | } | |
3000 | ||
1da177e4 LT |
3001 | skb->protocol = htons(ETH_P_IP); |
3002 | skb->dev = dev; | |
963bfeee | 3003 | skb->mark = mark; |
1da177e4 LT |
3004 | local_bh_disable(); |
3005 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
3006 | local_bh_enable(); | |
d889ce3b | 3007 | |
511c3f92 | 3008 | rt = skb_rtable(skb); |
d8d1f30b CG |
3009 | if (err == 0 && rt->dst.error) |
3010 | err = -rt->dst.error; | |
1da177e4 | 3011 | } else { |
68a5e3dd DM |
3012 | struct flowi4 fl4 = { |
3013 | .daddr = dst, | |
3014 | .saddr = src, | |
3015 | .flowi4_tos = rtm->rtm_tos, | |
3016 | .flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0, | |
3017 | .flowi4_mark = mark, | |
d889ce3b | 3018 | }; |
9d6ec938 | 3019 | rt = ip_route_output_key(net, &fl4); |
b23dd4fe DM |
3020 | |
3021 | err = 0; | |
3022 | if (IS_ERR(rt)) | |
3023 | err = PTR_ERR(rt); | |
1da177e4 | 3024 | } |
d889ce3b | 3025 | |
1da177e4 | 3026 | if (err) |
d889ce3b | 3027 | goto errout_free; |
1da177e4 | 3028 | |
d8d1f30b | 3029 | skb_dst_set(skb, &rt->dst); |
1da177e4 LT |
3030 | if (rtm->rtm_flags & RTM_F_NOTIFY) |
3031 | rt->rt_flags |= RTCF_NOTIFY; | |
3032 | ||
4feb88e5 | 3033 | err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, |
1937504d | 3034 | RTM_NEWROUTE, 0, 0); |
d889ce3b TG |
3035 | if (err <= 0) |
3036 | goto errout_free; | |
1da177e4 | 3037 | |
1937504d | 3038 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); |
d889ce3b | 3039 | errout: |
2942e900 | 3040 | return err; |
1da177e4 | 3041 | |
d889ce3b | 3042 | errout_free: |
1da177e4 | 3043 | kfree_skb(skb); |
d889ce3b | 3044 | goto errout; |
1da177e4 LT |
3045 | } |
3046 | ||
3047 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
3048 | { | |
3049 | struct rtable *rt; | |
3050 | int h, s_h; | |
3051 | int idx, s_idx; | |
1937504d DL |
3052 | struct net *net; |
3053 | ||
3b1e0a65 | 3054 | net = sock_net(skb->sk); |
1da177e4 LT |
3055 | |
3056 | s_h = cb->args[0]; | |
d8c92830 ED |
3057 | if (s_h < 0) |
3058 | s_h = 0; | |
1da177e4 | 3059 | s_idx = idx = cb->args[1]; |
a6272665 ED |
3060 | for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) { |
3061 | if (!rt_hash_table[h].chain) | |
3062 | continue; | |
1da177e4 | 3063 | rcu_read_lock_bh(); |
a898def2 | 3064 | for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt; |
d8d1f30b CG |
3065 | rt = rcu_dereference_bh(rt->dst.rt_next), idx++) { |
3066 | if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx) | |
1da177e4 | 3067 | continue; |
e84f84f2 | 3068 | if (rt_is_expired(rt)) |
29e75252 | 3069 | continue; |
d8d1f30b | 3070 | skb_dst_set_noref(skb, &rt->dst); |
4feb88e5 | 3071 | if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid, |
e905a9ed | 3072 | cb->nlh->nlmsg_seq, RTM_NEWROUTE, |
b6544c0b | 3073 | 1, NLM_F_MULTI) <= 0) { |
adf30907 | 3074 | skb_dst_drop(skb); |
1da177e4 LT |
3075 | rcu_read_unlock_bh(); |
3076 | goto done; | |
3077 | } | |
adf30907 | 3078 | skb_dst_drop(skb); |
1da177e4 LT |
3079 | } |
3080 | rcu_read_unlock_bh(); | |
3081 | } | |
3082 | ||
3083 | done: | |
3084 | cb->args[0] = h; | |
3085 | cb->args[1] = idx; | |
3086 | return skb->len; | |
3087 | } | |
3088 | ||
3089 | void ip_rt_multicast_event(struct in_device *in_dev) | |
3090 | { | |
76e6ebfb | 3091 | rt_cache_flush(dev_net(in_dev->dev), 0); |
1da177e4 LT |
3092 | } |
3093 | ||
3094 | #ifdef CONFIG_SYSCTL | |
81c684d1 | 3095 | static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, |
8d65af78 | 3096 | void __user *buffer, |
1da177e4 LT |
3097 | size_t *lenp, loff_t *ppos) |
3098 | { | |
3099 | if (write) { | |
639e104f | 3100 | int flush_delay; |
81c684d1 | 3101 | ctl_table ctl; |
39a23e75 | 3102 | struct net *net; |
639e104f | 3103 | |
81c684d1 DL |
3104 | memcpy(&ctl, __ctl, sizeof(ctl)); |
3105 | ctl.data = &flush_delay; | |
8d65af78 | 3106 | proc_dointvec(&ctl, write, buffer, lenp, ppos); |
639e104f | 3107 | |
81c684d1 | 3108 | net = (struct net *)__ctl->extra1; |
39a23e75 | 3109 | rt_cache_flush(net, flush_delay); |
1da177e4 | 3110 | return 0; |
e905a9ed | 3111 | } |
1da177e4 LT |
3112 | |
3113 | return -EINVAL; | |
3114 | } | |
3115 | ||
eeb61f71 | 3116 | static ctl_table ipv4_route_table[] = { |
1da177e4 | 3117 | { |
1da177e4 LT |
3118 | .procname = "gc_thresh", |
3119 | .data = &ipv4_dst_ops.gc_thresh, | |
3120 | .maxlen = sizeof(int), | |
3121 | .mode = 0644, | |
6d9f239a | 3122 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3123 | }, |
3124 | { | |
1da177e4 LT |
3125 | .procname = "max_size", |
3126 | .data = &ip_rt_max_size, | |
3127 | .maxlen = sizeof(int), | |
3128 | .mode = 0644, | |
6d9f239a | 3129 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3130 | }, |
3131 | { | |
3132 | /* Deprecated. Use gc_min_interval_ms */ | |
e905a9ed | 3133 | |
1da177e4 LT |
3134 | .procname = "gc_min_interval", |
3135 | .data = &ip_rt_gc_min_interval, | |
3136 | .maxlen = sizeof(int), | |
3137 | .mode = 0644, | |
6d9f239a | 3138 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3139 | }, |
3140 | { | |
1da177e4 LT |
3141 | .procname = "gc_min_interval_ms", |
3142 | .data = &ip_rt_gc_min_interval, | |
3143 | .maxlen = sizeof(int), | |
3144 | .mode = 0644, | |
6d9f239a | 3145 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 LT |
3146 | }, |
3147 | { | |
1da177e4 LT |
3148 | .procname = "gc_timeout", |
3149 | .data = &ip_rt_gc_timeout, | |
3150 | .maxlen = sizeof(int), | |
3151 | .mode = 0644, | |
6d9f239a | 3152 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 | 3153 | }, |
9f28a2fc ED |
3154 | { |
3155 | .procname = "gc_interval", | |
3156 | .data = &ip_rt_gc_interval, | |
3157 | .maxlen = sizeof(int), | |
3158 | .mode = 0644, | |
3159 | .proc_handler = proc_dointvec_jiffies, | |
3160 | }, | |
1da177e4 | 3161 | { |
1da177e4 LT |
3162 | .procname = "redirect_load", |
3163 | .data = &ip_rt_redirect_load, | |
3164 | .maxlen = sizeof(int), | |
3165 | .mode = 0644, | |
6d9f239a | 3166 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3167 | }, |
3168 | { | |
1da177e4 LT |
3169 | .procname = "redirect_number", |
3170 | .data = &ip_rt_redirect_number, | |
3171 | .maxlen = sizeof(int), | |
3172 | .mode = 0644, | |
6d9f239a | 3173 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3174 | }, |
3175 | { | |
1da177e4 LT |
3176 | .procname = "redirect_silence", |
3177 | .data = &ip_rt_redirect_silence, | |
3178 | .maxlen = sizeof(int), | |
3179 | .mode = 0644, | |
6d9f239a | 3180 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3181 | }, |
3182 | { | |
1da177e4 LT |
3183 | .procname = "error_cost", |
3184 | .data = &ip_rt_error_cost, | |
3185 | .maxlen = sizeof(int), | |
3186 | .mode = 0644, | |
6d9f239a | 3187 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3188 | }, |
3189 | { | |
1da177e4 LT |
3190 | .procname = "error_burst", |
3191 | .data = &ip_rt_error_burst, | |
3192 | .maxlen = sizeof(int), | |
3193 | .mode = 0644, | |
6d9f239a | 3194 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3195 | }, |
3196 | { | |
1da177e4 LT |
3197 | .procname = "gc_elasticity", |
3198 | .data = &ip_rt_gc_elasticity, | |
3199 | .maxlen = sizeof(int), | |
3200 | .mode = 0644, | |
6d9f239a | 3201 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3202 | }, |
3203 | { | |
1da177e4 LT |
3204 | .procname = "mtu_expires", |
3205 | .data = &ip_rt_mtu_expires, | |
3206 | .maxlen = sizeof(int), | |
3207 | .mode = 0644, | |
6d9f239a | 3208 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
3209 | }, |
3210 | { | |
1da177e4 LT |
3211 | .procname = "min_pmtu", |
3212 | .data = &ip_rt_min_pmtu, | |
3213 | .maxlen = sizeof(int), | |
3214 | .mode = 0644, | |
6d9f239a | 3215 | .proc_handler = proc_dointvec, |
1da177e4 LT |
3216 | }, |
3217 | { | |
1da177e4 LT |
3218 | .procname = "min_adv_mss", |
3219 | .data = &ip_rt_min_advmss, | |
3220 | .maxlen = sizeof(int), | |
3221 | .mode = 0644, | |
6d9f239a | 3222 | .proc_handler = proc_dointvec, |
1da177e4 | 3223 | }, |
f8572d8f | 3224 | { } |
1da177e4 | 3225 | }; |
39a23e75 | 3226 | |
39a23e75 DL |
3227 | static struct ctl_table ipv4_route_flush_table[] = { |
3228 | { | |
39a23e75 DL |
3229 | .procname = "flush", |
3230 | .maxlen = sizeof(int), | |
3231 | .mode = 0200, | |
6d9f239a | 3232 | .proc_handler = ipv4_sysctl_rtcache_flush, |
39a23e75 | 3233 | }, |
f8572d8f | 3234 | { }, |
39a23e75 DL |
3235 | }; |
3236 | ||
3237 | static __net_init int sysctl_route_net_init(struct net *net) | |
3238 | { | |
3239 | struct ctl_table *tbl; | |
3240 | ||
3241 | tbl = ipv4_route_flush_table; | |
09ad9bc7 | 3242 | if (!net_eq(net, &init_net)) { |
39a23e75 DL |
3243 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); |
3244 | if (tbl == NULL) | |
3245 | goto err_dup; | |
3246 | } | |
3247 | tbl[0].extra1 = net; | |
3248 | ||
ec8f23ce | 3249 | net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl); |
39a23e75 DL |
3250 | if (net->ipv4.route_hdr == NULL) |
3251 | goto err_reg; | |
3252 | return 0; | |
3253 | ||
3254 | err_reg: | |
3255 | if (tbl != ipv4_route_flush_table) | |
3256 | kfree(tbl); | |
3257 | err_dup: | |
3258 | return -ENOMEM; | |
3259 | } | |
3260 | ||
3261 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
3262 | { | |
3263 | struct ctl_table *tbl; | |
3264 | ||
3265 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
3266 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
3267 | BUG_ON(tbl == ipv4_route_flush_table); | |
3268 | kfree(tbl); | |
3269 | } | |
3270 | ||
3271 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
3272 | .init = sysctl_route_net_init, | |
3273 | .exit = sysctl_route_net_exit, | |
3274 | }; | |
1da177e4 LT |
3275 | #endif |
3276 | ||
3ee94372 | 3277 | static __net_init int rt_genid_init(struct net *net) |
9f5e97e5 | 3278 | { |
3ee94372 NH |
3279 | get_random_bytes(&net->ipv4.rt_genid, |
3280 | sizeof(net->ipv4.rt_genid)); | |
436c3b66 DM |
3281 | get_random_bytes(&net->ipv4.dev_addr_genid, |
3282 | sizeof(net->ipv4.dev_addr_genid)); | |
9f5e97e5 DL |
3283 | return 0; |
3284 | } | |
3285 | ||
3ee94372 NH |
3286 | static __net_initdata struct pernet_operations rt_genid_ops = { |
3287 | .init = rt_genid_init, | |
9f5e97e5 DL |
3288 | }; |
3289 | ||
c3426b47 DM |
3290 | static int __net_init ipv4_inetpeer_init(struct net *net) |
3291 | { | |
3292 | struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL); | |
3293 | ||
3294 | if (!bp) | |
3295 | return -ENOMEM; | |
3296 | inet_peer_base_init(bp); | |
3297 | net->ipv4.peers = bp; | |
3298 | return 0; | |
3299 | } | |
3300 | ||
3301 | static void __net_exit ipv4_inetpeer_exit(struct net *net) | |
3302 | { | |
3303 | struct inet_peer_base *bp = net->ipv4.peers; | |
3304 | ||
3305 | net->ipv4.peers = NULL; | |
56a6b248 | 3306 | inetpeer_invalidate_tree(bp); |
c3426b47 DM |
3307 | kfree(bp); |
3308 | } | |
3309 | ||
3310 | static __net_initdata struct pernet_operations ipv4_inetpeer_ops = { | |
3311 | .init = ipv4_inetpeer_init, | |
3312 | .exit = ipv4_inetpeer_exit, | |
3313 | }; | |
9f5e97e5 | 3314 | |
c7066f70 | 3315 | #ifdef CONFIG_IP_ROUTE_CLASSID |
7d720c3e | 3316 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; |
c7066f70 | 3317 | #endif /* CONFIG_IP_ROUTE_CLASSID */ |
1da177e4 LT |
3318 | |
3319 | static __initdata unsigned long rhash_entries; | |
3320 | static int __init set_rhash_entries(char *str) | |
3321 | { | |
413c27d8 EZ |
3322 | ssize_t ret; |
3323 | ||
1da177e4 LT |
3324 | if (!str) |
3325 | return 0; | |
413c27d8 EZ |
3326 | |
3327 | ret = kstrtoul(str, 0, &rhash_entries); | |
3328 | if (ret) | |
3329 | return 0; | |
3330 | ||
1da177e4 LT |
3331 | return 1; |
3332 | } | |
3333 | __setup("rhash_entries=", set_rhash_entries); | |
3334 | ||
3335 | int __init ip_rt_init(void) | |
3336 | { | |
424c4b70 | 3337 | int rc = 0; |
1da177e4 | 3338 | |
c7066f70 | 3339 | #ifdef CONFIG_IP_ROUTE_CLASSID |
0dcec8c2 | 3340 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); |
1da177e4 LT |
3341 | if (!ip_rt_acct) |
3342 | panic("IP: failed to allocate ip_rt_acct\n"); | |
1da177e4 LT |
3343 | #endif |
3344 | ||
e5d679f3 AD |
3345 | ipv4_dst_ops.kmem_cachep = |
3346 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
20c2df83 | 3347 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 3348 | |
14e50e57 DM |
3349 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; |
3350 | ||
fc66f95c ED |
3351 | if (dst_entries_init(&ipv4_dst_ops) < 0) |
3352 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
3353 | ||
3354 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
3355 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
3356 | ||
424c4b70 ED |
3357 | rt_hash_table = (struct rt_hash_bucket *) |
3358 | alloc_large_system_hash("IP route cache", | |
3359 | sizeof(struct rt_hash_bucket), | |
3360 | rhash_entries, | |
4481374c | 3361 | (totalram_pages >= 128 * 1024) ? |
18955cfc | 3362 | 15 : 17, |
8d1502de | 3363 | 0, |
424c4b70 ED |
3364 | &rt_hash_log, |
3365 | &rt_hash_mask, | |
31fe62b9 | 3366 | 0, |
c9503e0f | 3367 | rhash_entries ? 0 : 512 * 1024); |
22c047cc ED |
3368 | memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket)); |
3369 | rt_hash_lock_init(); | |
1da177e4 LT |
3370 | |
3371 | ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1); | |
3372 | ip_rt_max_size = (rt_hash_mask + 1) * 16; | |
3373 | ||
1da177e4 LT |
3374 | devinet_init(); |
3375 | ip_fib_init(); | |
3376 | ||
9f28a2fc ED |
3377 | INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func); |
3378 | expires_ljiffies = jiffies; | |
3379 | schedule_delayed_work(&expires_work, | |
3380 | net_random() % ip_rt_gc_interval + ip_rt_gc_interval); | |
3381 | ||
73b38711 | 3382 | if (ip_rt_proc_init()) |
058bd4d2 | 3383 | pr_err("Unable to create route proc files\n"); |
1da177e4 LT |
3384 | #ifdef CONFIG_XFRM |
3385 | xfrm_init(); | |
a33bc5c1 | 3386 | xfrm4_init(ip_rt_max_size); |
1da177e4 | 3387 | #endif |
c7ac8679 | 3388 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL); |
63f3444f | 3389 | |
39a23e75 DL |
3390 | #ifdef CONFIG_SYSCTL |
3391 | register_pernet_subsys(&sysctl_route_ops); | |
3392 | #endif | |
3ee94372 | 3393 | register_pernet_subsys(&rt_genid_ops); |
c3426b47 | 3394 | register_pernet_subsys(&ipv4_inetpeer_ops); |
1da177e4 LT |
3395 | return rc; |
3396 | } | |
3397 | ||
a1bc6eb4 | 3398 | #ifdef CONFIG_SYSCTL |
eeb61f71 AV |
3399 | /* |
3400 | * We really need to sanitize the damn ipv4 init order, then all | |
3401 | * this nonsense will go away. | |
3402 | */ | |
3403 | void __init ip_static_sysctl_init(void) | |
3404 | { | |
4e5ca785 | 3405 | register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table); |
eeb61f71 | 3406 | } |
a1bc6eb4 | 3407 | #endif |