Commit | Line | Data |
---|---|---|
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 LT |
72 | #include <linux/mm.h> |
73 | #include <linux/string.h> | |
74 | #include <linux/socket.h> | |
75 | #include <linux/sockios.h> | |
76 | #include <linux/errno.h> | |
77 | #include <linux/in.h> | |
78 | #include <linux/inet.h> | |
79 | #include <linux/netdevice.h> | |
80 | #include <linux/proc_fs.h> | |
81 | #include <linux/init.h> | |
82 | #include <linux/skbuff.h> | |
1da177e4 LT |
83 | #include <linux/inetdevice.h> |
84 | #include <linux/igmp.h> | |
85 | #include <linux/pkt_sched.h> | |
86 | #include <linux/mroute.h> | |
87 | #include <linux/netfilter_ipv4.h> | |
88 | #include <linux/random.h> | |
1da177e4 LT |
89 | #include <linux/rcupdate.h> |
90 | #include <linux/times.h> | |
5a0e3ad6 | 91 | #include <linux/slab.h> |
352e512c | 92 | #include <net/dst.h> |
457c4cbc | 93 | #include <net/net_namespace.h> |
1da177e4 LT |
94 | #include <net/protocol.h> |
95 | #include <net/ip.h> | |
96 | #include <net/route.h> | |
97 | #include <net/inetpeer.h> | |
98 | #include <net/sock.h> | |
99 | #include <net/ip_fib.h> | |
100 | #include <net/arp.h> | |
101 | #include <net/tcp.h> | |
102 | #include <net/icmp.h> | |
103 | #include <net/xfrm.h> | |
8d71740c | 104 | #include <net/netevent.h> |
63f3444f | 105 | #include <net/rtnetlink.h> |
1da177e4 LT |
106 | #ifdef CONFIG_SYSCTL |
107 | #include <linux/sysctl.h> | |
7426a564 | 108 | #include <linux/kmemleak.h> |
1da177e4 | 109 | #endif |
6e5714ea | 110 | #include <net/secure_seq.h> |
1da177e4 | 111 | |
68a5e3dd | 112 | #define RT_FL_TOS(oldflp4) \ |
f61759e6 | 113 | ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) |
1da177e4 LT |
114 | |
115 | #define IP_MAX_MTU 0xFFF0 | |
116 | ||
117 | #define RT_GC_TIMEOUT (300*HZ) | |
118 | ||
1da177e4 | 119 | static int ip_rt_max_size; |
817bc4db | 120 | static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; |
9f28a2fc | 121 | static int ip_rt_gc_interval __read_mostly = 60 * HZ; |
817bc4db SH |
122 | static int ip_rt_gc_min_interval __read_mostly = HZ / 2; |
123 | static int ip_rt_redirect_number __read_mostly = 9; | |
124 | static int ip_rt_redirect_load __read_mostly = HZ / 50; | |
125 | static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); | |
126 | static int ip_rt_error_cost __read_mostly = HZ; | |
127 | static int ip_rt_error_burst __read_mostly = 5 * HZ; | |
128 | static int ip_rt_gc_elasticity __read_mostly = 8; | |
129 | static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; | |
130 | static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; | |
131 | static int ip_rt_min_advmss __read_mostly = 256; | |
9f28a2fc | 132 | |
1da177e4 LT |
133 | /* |
134 | * Interface to generic destination cache. | |
135 | */ | |
136 | ||
137 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
0dbaee3b | 138 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst); |
ebb762f2 | 139 | static unsigned int ipv4_mtu(const struct dst_entry *dst); |
1da177e4 LT |
140 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); |
141 | static void ipv4_link_failure(struct sk_buff *skb); | |
6700c270 DM |
142 | static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, |
143 | struct sk_buff *skb, u32 mtu); | |
144 | static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, | |
145 | struct sk_buff *skb); | |
caacf05e | 146 | static void ipv4_dst_destroy(struct dst_entry *dst); |
1da177e4 | 147 | |
72cdd1d9 ED |
148 | static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, |
149 | int how) | |
150 | { | |
151 | } | |
1da177e4 | 152 | |
62fa8a84 DM |
153 | static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) |
154 | { | |
31248731 DM |
155 | WARN_ON(1); |
156 | return NULL; | |
62fa8a84 DM |
157 | } |
158 | ||
f894cbf8 DM |
159 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, |
160 | struct sk_buff *skb, | |
161 | const void *daddr); | |
d3aaeb38 | 162 | |
1da177e4 LT |
163 | static struct dst_ops ipv4_dst_ops = { |
164 | .family = AF_INET, | |
09640e63 | 165 | .protocol = cpu_to_be16(ETH_P_IP), |
1da177e4 | 166 | .check = ipv4_dst_check, |
0dbaee3b | 167 | .default_advmss = ipv4_default_advmss, |
ebb762f2 | 168 | .mtu = ipv4_mtu, |
62fa8a84 | 169 | .cow_metrics = ipv4_cow_metrics, |
caacf05e | 170 | .destroy = ipv4_dst_destroy, |
1da177e4 LT |
171 | .ifdown = ipv4_dst_ifdown, |
172 | .negative_advice = ipv4_negative_advice, | |
173 | .link_failure = ipv4_link_failure, | |
174 | .update_pmtu = ip_rt_update_pmtu, | |
e47a185b | 175 | .redirect = ip_do_redirect, |
1ac06e03 | 176 | .local_out = __ip_local_out, |
d3aaeb38 | 177 | .neigh_lookup = ipv4_neigh_lookup, |
1da177e4 LT |
178 | }; |
179 | ||
180 | #define ECN_OR_COST(class) TC_PRIO_##class | |
181 | ||
4839c52b | 182 | const __u8 ip_tos2prio[16] = { |
1da177e4 | 183 | TC_PRIO_BESTEFFORT, |
4a2b9c37 | 184 | ECN_OR_COST(BESTEFFORT), |
1da177e4 LT |
185 | TC_PRIO_BESTEFFORT, |
186 | ECN_OR_COST(BESTEFFORT), | |
187 | TC_PRIO_BULK, | |
188 | ECN_OR_COST(BULK), | |
189 | TC_PRIO_BULK, | |
190 | ECN_OR_COST(BULK), | |
191 | TC_PRIO_INTERACTIVE, | |
192 | ECN_OR_COST(INTERACTIVE), | |
193 | TC_PRIO_INTERACTIVE, | |
194 | ECN_OR_COST(INTERACTIVE), | |
195 | TC_PRIO_INTERACTIVE_BULK, | |
196 | ECN_OR_COST(INTERACTIVE_BULK), | |
197 | TC_PRIO_INTERACTIVE_BULK, | |
198 | ECN_OR_COST(INTERACTIVE_BULK) | |
199 | }; | |
d4a96865 | 200 | EXPORT_SYMBOL(ip_tos2prio); |
1da177e4 | 201 | |
2f970d83 | 202 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); |
27f39c73 | 203 | #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field) |
1da177e4 | 204 | |
1da177e4 | 205 | #ifdef CONFIG_PROC_FS |
1da177e4 LT |
206 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) |
207 | { | |
29e75252 | 208 | if (*pos) |
89aef892 | 209 | return NULL; |
29e75252 | 210 | return SEQ_START_TOKEN; |
1da177e4 LT |
211 | } |
212 | ||
213 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
214 | { | |
1da177e4 | 215 | ++*pos; |
89aef892 | 216 | return NULL; |
1da177e4 LT |
217 | } |
218 | ||
219 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
220 | { | |
1da177e4 LT |
221 | } |
222 | ||
223 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
224 | { | |
225 | if (v == SEQ_START_TOKEN) | |
226 | seq_printf(seq, "%-127s\n", | |
227 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
228 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
229 | "HHUptod\tSpecDst"); | |
e905a9ed | 230 | return 0; |
1da177e4 LT |
231 | } |
232 | ||
f690808e | 233 | static const struct seq_operations rt_cache_seq_ops = { |
1da177e4 LT |
234 | .start = rt_cache_seq_start, |
235 | .next = rt_cache_seq_next, | |
236 | .stop = rt_cache_seq_stop, | |
237 | .show = rt_cache_seq_show, | |
238 | }; | |
239 | ||
240 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
241 | { | |
89aef892 | 242 | return seq_open(file, &rt_cache_seq_ops); |
1da177e4 LT |
243 | } |
244 | ||
9a32144e | 245 | static const struct file_operations rt_cache_seq_fops = { |
1da177e4 LT |
246 | .owner = THIS_MODULE, |
247 | .open = rt_cache_seq_open, | |
248 | .read = seq_read, | |
249 | .llseek = seq_lseek, | |
89aef892 | 250 | .release = seq_release, |
1da177e4 LT |
251 | }; |
252 | ||
253 | ||
254 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
255 | { | |
256 | int cpu; | |
257 | ||
258 | if (*pos == 0) | |
259 | return SEQ_START_TOKEN; | |
260 | ||
0f23174a | 261 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
262 | if (!cpu_possible(cpu)) |
263 | continue; | |
264 | *pos = cpu+1; | |
2f970d83 | 265 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
266 | } |
267 | return NULL; | |
268 | } | |
269 | ||
270 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
271 | { | |
272 | int cpu; | |
273 | ||
0f23174a | 274 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
275 | if (!cpu_possible(cpu)) |
276 | continue; | |
277 | *pos = cpu+1; | |
2f970d83 | 278 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
279 | } |
280 | return NULL; | |
e905a9ed | 281 | |
1da177e4 LT |
282 | } |
283 | ||
284 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
285 | { | |
286 | ||
287 | } | |
288 | ||
289 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
290 | { | |
291 | struct rt_cache_stat *st = v; | |
292 | ||
293 | if (v == SEQ_START_TOKEN) { | |
5bec0039 | 294 | 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 |
295 | return 0; |
296 | } | |
e905a9ed | 297 | |
1da177e4 LT |
298 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " |
299 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
fc66f95c | 300 | dst_entries_get_slow(&ipv4_dst_ops), |
1da177e4 LT |
301 | st->in_hit, |
302 | st->in_slow_tot, | |
303 | st->in_slow_mc, | |
304 | st->in_no_route, | |
305 | st->in_brd, | |
306 | st->in_martian_dst, | |
307 | st->in_martian_src, | |
308 | ||
309 | st->out_hit, | |
310 | st->out_slow_tot, | |
e905a9ed | 311 | st->out_slow_mc, |
1da177e4 LT |
312 | |
313 | st->gc_total, | |
314 | st->gc_ignored, | |
315 | st->gc_goal_miss, | |
316 | st->gc_dst_overflow, | |
317 | st->in_hlist_search, | |
318 | st->out_hlist_search | |
319 | ); | |
320 | return 0; | |
321 | } | |
322 | ||
f690808e | 323 | static const struct seq_operations rt_cpu_seq_ops = { |
1da177e4 LT |
324 | .start = rt_cpu_seq_start, |
325 | .next = rt_cpu_seq_next, | |
326 | .stop = rt_cpu_seq_stop, | |
327 | .show = rt_cpu_seq_show, | |
328 | }; | |
329 | ||
330 | ||
331 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
332 | { | |
333 | return seq_open(file, &rt_cpu_seq_ops); | |
334 | } | |
335 | ||
9a32144e | 336 | static const struct file_operations rt_cpu_seq_fops = { |
1da177e4 LT |
337 | .owner = THIS_MODULE, |
338 | .open = rt_cpu_seq_open, | |
339 | .read = seq_read, | |
340 | .llseek = seq_lseek, | |
341 | .release = seq_release, | |
342 | }; | |
343 | ||
c7066f70 | 344 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 345 | static int rt_acct_proc_show(struct seq_file *m, void *v) |
78c686e9 | 346 | { |
a661c419 AD |
347 | struct ip_rt_acct *dst, *src; |
348 | unsigned int i, j; | |
349 | ||
350 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
351 | if (!dst) | |
352 | return -ENOMEM; | |
353 | ||
354 | for_each_possible_cpu(i) { | |
355 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
356 | for (j = 0; j < 256; j++) { | |
357 | dst[j].o_bytes += src[j].o_bytes; | |
358 | dst[j].o_packets += src[j].o_packets; | |
359 | dst[j].i_bytes += src[j].i_bytes; | |
360 | dst[j].i_packets += src[j].i_packets; | |
361 | } | |
78c686e9 PE |
362 | } |
363 | ||
a661c419 AD |
364 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); |
365 | kfree(dst); | |
366 | return 0; | |
367 | } | |
78c686e9 | 368 | |
a661c419 AD |
369 | static int rt_acct_proc_open(struct inode *inode, struct file *file) |
370 | { | |
371 | return single_open(file, rt_acct_proc_show, NULL); | |
78c686e9 | 372 | } |
a661c419 AD |
373 | |
374 | static const struct file_operations rt_acct_proc_fops = { | |
375 | .owner = THIS_MODULE, | |
376 | .open = rt_acct_proc_open, | |
377 | .read = seq_read, | |
378 | .llseek = seq_lseek, | |
379 | .release = single_release, | |
380 | }; | |
78c686e9 | 381 | #endif |
107f1634 | 382 | |
73b38711 | 383 | static int __net_init ip_rt_do_proc_init(struct net *net) |
107f1634 PE |
384 | { |
385 | struct proc_dir_entry *pde; | |
386 | ||
387 | pde = proc_net_fops_create(net, "rt_cache", S_IRUGO, | |
388 | &rt_cache_seq_fops); | |
389 | if (!pde) | |
390 | goto err1; | |
391 | ||
77020720 WC |
392 | pde = proc_create("rt_cache", S_IRUGO, |
393 | net->proc_net_stat, &rt_cpu_seq_fops); | |
107f1634 PE |
394 | if (!pde) |
395 | goto err2; | |
396 | ||
c7066f70 | 397 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 398 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); |
107f1634 PE |
399 | if (!pde) |
400 | goto err3; | |
401 | #endif | |
402 | return 0; | |
403 | ||
c7066f70 | 404 | #ifdef CONFIG_IP_ROUTE_CLASSID |
107f1634 PE |
405 | err3: |
406 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
407 | #endif | |
408 | err2: | |
409 | remove_proc_entry("rt_cache", net->proc_net); | |
410 | err1: | |
411 | return -ENOMEM; | |
412 | } | |
73b38711 DL |
413 | |
414 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
415 | { | |
416 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
417 | remove_proc_entry("rt_cache", net->proc_net); | |
c7066f70 | 418 | #ifdef CONFIG_IP_ROUTE_CLASSID |
73b38711 | 419 | remove_proc_entry("rt_acct", net->proc_net); |
0a931acf | 420 | #endif |
73b38711 DL |
421 | } |
422 | ||
423 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
424 | .init = ip_rt_do_proc_init, | |
425 | .exit = ip_rt_do_proc_exit, | |
426 | }; | |
427 | ||
428 | static int __init ip_rt_proc_init(void) | |
429 | { | |
430 | return register_pernet_subsys(&ip_rt_proc_ops); | |
431 | } | |
432 | ||
107f1634 | 433 | #else |
73b38711 | 434 | static inline int ip_rt_proc_init(void) |
107f1634 PE |
435 | { |
436 | return 0; | |
437 | } | |
1da177e4 | 438 | #endif /* CONFIG_PROC_FS */ |
e905a9ed | 439 | |
4331debc | 440 | static inline bool rt_is_expired(const struct rtable *rth) |
e84f84f2 | 441 | { |
d8d1f30b | 442 | return rth->rt_genid != rt_genid(dev_net(rth->dst.dev)); |
e84f84f2 DL |
443 | } |
444 | ||
4ccfe6d4 | 445 | void rt_cache_flush(struct net *net) |
1da177e4 | 446 | { |
b42664f8 | 447 | rt_genid_bump(net); |
98376387 ED |
448 | } |
449 | ||
f894cbf8 DM |
450 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, |
451 | struct sk_buff *skb, | |
452 | const void *daddr) | |
3769cffb | 453 | { |
d3aaeb38 DM |
454 | struct net_device *dev = dst->dev; |
455 | const __be32 *pkey = daddr; | |
39232973 | 456 | const struct rtable *rt; |
3769cffb DM |
457 | struct neighbour *n; |
458 | ||
39232973 | 459 | rt = (const struct rtable *) dst; |
a263b309 | 460 | if (rt->rt_gateway) |
39232973 | 461 | pkey = (const __be32 *) &rt->rt_gateway; |
f894cbf8 DM |
462 | else if (skb) |
463 | pkey = &ip_hdr(skb)->daddr; | |
d3aaeb38 | 464 | |
80703d26 | 465 | n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey); |
d3aaeb38 DM |
466 | if (n) |
467 | return n; | |
32092ecf | 468 | return neigh_create(&arp_tbl, pkey, dev); |
d3aaeb38 DM |
469 | } |
470 | ||
1da177e4 LT |
471 | /* |
472 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
473 | * we still can generate some output. | |
474 | * Random ID selection looks a bit dangerous because we have no chances to | |
475 | * select ID being unique in a reasonable period of time. | |
476 | * But broken packet identifier may be better than no packet at all. | |
477 | */ | |
478 | static void ip_select_fb_ident(struct iphdr *iph) | |
479 | { | |
480 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
481 | static u32 ip_fallback_id; | |
482 | u32 salt; | |
483 | ||
484 | spin_lock_bh(&ip_fb_id_lock); | |
e448515c | 485 | salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr); |
1da177e4 LT |
486 | iph->id = htons(salt & 0xFFFF); |
487 | ip_fallback_id = salt; | |
488 | spin_unlock_bh(&ip_fb_id_lock); | |
489 | } | |
490 | ||
491 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
492 | { | |
1d861aa4 DM |
493 | struct net *net = dev_net(dst->dev); |
494 | struct inet_peer *peer; | |
1da177e4 | 495 | |
1d861aa4 DM |
496 | peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1); |
497 | if (peer) { | |
498 | iph->id = htons(inet_getid(peer, more)); | |
499 | inet_putpeer(peer); | |
500 | return; | |
501 | } | |
1da177e4 LT |
502 | |
503 | ip_select_fb_ident(iph); | |
504 | } | |
4bc2f18b | 505 | EXPORT_SYMBOL(__ip_select_ident); |
1da177e4 | 506 | |
5abf7f7e | 507 | static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk, |
4895c771 DM |
508 | const struct iphdr *iph, |
509 | int oif, u8 tos, | |
510 | u8 prot, u32 mark, int flow_flags) | |
511 | { | |
512 | if (sk) { | |
513 | const struct inet_sock *inet = inet_sk(sk); | |
514 | ||
515 | oif = sk->sk_bound_dev_if; | |
516 | mark = sk->sk_mark; | |
517 | tos = RT_CONN_FLAGS(sk); | |
518 | prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol; | |
519 | } | |
520 | flowi4_init_output(fl4, oif, mark, tos, | |
521 | RT_SCOPE_UNIVERSE, prot, | |
522 | flow_flags, | |
523 | iph->daddr, iph->saddr, 0, 0); | |
524 | } | |
525 | ||
5abf7f7e ED |
526 | static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb, |
527 | const struct sock *sk) | |
4895c771 DM |
528 | { |
529 | const struct iphdr *iph = ip_hdr(skb); | |
530 | int oif = skb->dev->ifindex; | |
531 | u8 tos = RT_TOS(iph->tos); | |
532 | u8 prot = iph->protocol; | |
533 | u32 mark = skb->mark; | |
534 | ||
535 | __build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0); | |
536 | } | |
537 | ||
5abf7f7e | 538 | static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk) |
4895c771 DM |
539 | { |
540 | const struct inet_sock *inet = inet_sk(sk); | |
5abf7f7e | 541 | const struct ip_options_rcu *inet_opt; |
4895c771 DM |
542 | __be32 daddr = inet->inet_daddr; |
543 | ||
544 | rcu_read_lock(); | |
545 | inet_opt = rcu_dereference(inet->inet_opt); | |
546 | if (inet_opt && inet_opt->opt.srr) | |
547 | daddr = inet_opt->opt.faddr; | |
548 | flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark, | |
549 | RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, | |
550 | inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, | |
551 | inet_sk_flowi_flags(sk), | |
552 | daddr, inet->inet_saddr, 0, 0); | |
553 | rcu_read_unlock(); | |
554 | } | |
555 | ||
5abf7f7e ED |
556 | static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk, |
557 | const struct sk_buff *skb) | |
4895c771 DM |
558 | { |
559 | if (skb) | |
560 | build_skb_flow_key(fl4, skb, sk); | |
561 | else | |
562 | build_sk_flow_key(fl4, sk); | |
563 | } | |
564 | ||
c5038a83 DM |
565 | static inline void rt_free(struct rtable *rt) |
566 | { | |
567 | call_rcu(&rt->dst.rcu_head, dst_rcu_free); | |
568 | } | |
569 | ||
570 | static DEFINE_SPINLOCK(fnhe_lock); | |
4895c771 | 571 | |
aee06da6 | 572 | static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash) |
4895c771 DM |
573 | { |
574 | struct fib_nh_exception *fnhe, *oldest; | |
c5038a83 | 575 | struct rtable *orig; |
4895c771 DM |
576 | |
577 | oldest = rcu_dereference(hash->chain); | |
578 | for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe; | |
579 | fnhe = rcu_dereference(fnhe->fnhe_next)) { | |
580 | if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp)) | |
581 | oldest = fnhe; | |
582 | } | |
c5038a83 DM |
583 | orig = rcu_dereference(oldest->fnhe_rth); |
584 | if (orig) { | |
585 | RCU_INIT_POINTER(oldest->fnhe_rth, NULL); | |
586 | rt_free(orig); | |
587 | } | |
4895c771 DM |
588 | return oldest; |
589 | } | |
590 | ||
d3a25c98 DM |
591 | static inline u32 fnhe_hashfun(__be32 daddr) |
592 | { | |
593 | u32 hval; | |
594 | ||
595 | hval = (__force u32) daddr; | |
596 | hval ^= (hval >> 11) ^ (hval >> 22); | |
597 | ||
598 | return hval & (FNHE_HASH_SIZE - 1); | |
599 | } | |
600 | ||
aee06da6 JA |
601 | static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw, |
602 | u32 pmtu, unsigned long expires) | |
4895c771 | 603 | { |
aee06da6 | 604 | struct fnhe_hash_bucket *hash; |
4895c771 DM |
605 | struct fib_nh_exception *fnhe; |
606 | int depth; | |
aee06da6 JA |
607 | u32 hval = fnhe_hashfun(daddr); |
608 | ||
c5038a83 | 609 | spin_lock_bh(&fnhe_lock); |
4895c771 | 610 | |
aee06da6 | 611 | hash = nh->nh_exceptions; |
4895c771 | 612 | if (!hash) { |
aee06da6 | 613 | hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC); |
4895c771 | 614 | if (!hash) |
aee06da6 JA |
615 | goto out_unlock; |
616 | nh->nh_exceptions = hash; | |
4895c771 DM |
617 | } |
618 | ||
4895c771 DM |
619 | hash += hval; |
620 | ||
621 | depth = 0; | |
622 | for (fnhe = rcu_dereference(hash->chain); fnhe; | |
623 | fnhe = rcu_dereference(fnhe->fnhe_next)) { | |
624 | if (fnhe->fnhe_daddr == daddr) | |
aee06da6 | 625 | break; |
4895c771 DM |
626 | depth++; |
627 | } | |
628 | ||
aee06da6 JA |
629 | if (fnhe) { |
630 | if (gw) | |
631 | fnhe->fnhe_gw = gw; | |
632 | if (pmtu) { | |
633 | fnhe->fnhe_pmtu = pmtu; | |
634 | fnhe->fnhe_expires = expires; | |
635 | } | |
636 | } else { | |
637 | if (depth > FNHE_RECLAIM_DEPTH) | |
638 | fnhe = fnhe_oldest(hash); | |
639 | else { | |
640 | fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC); | |
641 | if (!fnhe) | |
642 | goto out_unlock; | |
643 | ||
644 | fnhe->fnhe_next = hash->chain; | |
645 | rcu_assign_pointer(hash->chain, fnhe); | |
646 | } | |
647 | fnhe->fnhe_daddr = daddr; | |
648 | fnhe->fnhe_gw = gw; | |
649 | fnhe->fnhe_pmtu = pmtu; | |
650 | fnhe->fnhe_expires = expires; | |
4895c771 | 651 | } |
4895c771 | 652 | |
4895c771 | 653 | fnhe->fnhe_stamp = jiffies; |
aee06da6 JA |
654 | |
655 | out_unlock: | |
c5038a83 | 656 | spin_unlock_bh(&fnhe_lock); |
aee06da6 | 657 | return; |
4895c771 DM |
658 | } |
659 | ||
ceb33206 DM |
660 | static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4, |
661 | bool kill_route) | |
1da177e4 | 662 | { |
e47a185b | 663 | __be32 new_gw = icmp_hdr(skb)->un.gateway; |
94206125 | 664 | __be32 old_gw = ip_hdr(skb)->saddr; |
e47a185b | 665 | struct net_device *dev = skb->dev; |
e47a185b | 666 | struct in_device *in_dev; |
4895c771 | 667 | struct fib_result res; |
e47a185b | 668 | struct neighbour *n; |
317805b8 | 669 | struct net *net; |
1da177e4 | 670 | |
94206125 DM |
671 | switch (icmp_hdr(skb)->code & 7) { |
672 | case ICMP_REDIR_NET: | |
673 | case ICMP_REDIR_NETTOS: | |
674 | case ICMP_REDIR_HOST: | |
675 | case ICMP_REDIR_HOSTTOS: | |
676 | break; | |
677 | ||
678 | default: | |
679 | return; | |
680 | } | |
681 | ||
e47a185b DM |
682 | if (rt->rt_gateway != old_gw) |
683 | return; | |
684 | ||
685 | in_dev = __in_dev_get_rcu(dev); | |
686 | if (!in_dev) | |
687 | return; | |
688 | ||
c346dca1 | 689 | net = dev_net(dev); |
9d4fb27d JP |
690 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || |
691 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
692 | ipv4_is_zeronet(new_gw)) | |
1da177e4 LT |
693 | goto reject_redirect; |
694 | ||
695 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
696 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
697 | goto reject_redirect; | |
698 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
699 | goto reject_redirect; | |
700 | } else { | |
317805b8 | 701 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) |
1da177e4 LT |
702 | goto reject_redirect; |
703 | } | |
704 | ||
4895c771 | 705 | n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw); |
e47a185b DM |
706 | if (n) { |
707 | if (!(n->nud_state & NUD_VALID)) { | |
708 | neigh_event_send(n, NULL); | |
709 | } else { | |
4895c771 DM |
710 | if (fib_lookup(net, fl4, &res) == 0) { |
711 | struct fib_nh *nh = &FIB_RES_NH(res); | |
4895c771 | 712 | |
aee06da6 JA |
713 | update_or_create_fnhe(nh, fl4->daddr, new_gw, |
714 | 0, 0); | |
4895c771 | 715 | } |
ceb33206 DM |
716 | if (kill_route) |
717 | rt->dst.obsolete = DST_OBSOLETE_KILL; | |
e47a185b DM |
718 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); |
719 | } | |
720 | neigh_release(n); | |
721 | } | |
722 | return; | |
723 | ||
724 | reject_redirect: | |
725 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
99ee038d DM |
726 | if (IN_DEV_LOG_MARTIANS(in_dev)) { |
727 | const struct iphdr *iph = (const struct iphdr *) skb->data; | |
728 | __be32 daddr = iph->daddr; | |
729 | __be32 saddr = iph->saddr; | |
730 | ||
e47a185b DM |
731 | net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n" |
732 | " Advised path = %pI4 -> %pI4\n", | |
733 | &old_gw, dev->name, &new_gw, | |
734 | &saddr, &daddr); | |
99ee038d | 735 | } |
e47a185b DM |
736 | #endif |
737 | ; | |
738 | } | |
739 | ||
4895c771 DM |
740 | static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb) |
741 | { | |
742 | struct rtable *rt; | |
743 | struct flowi4 fl4; | |
744 | ||
745 | rt = (struct rtable *) dst; | |
746 | ||
747 | ip_rt_build_flow_key(&fl4, sk, skb); | |
ceb33206 | 748 | __ip_do_redirect(rt, skb, &fl4, true); |
4895c771 DM |
749 | } |
750 | ||
1da177e4 LT |
751 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) |
752 | { | |
ee6b9673 | 753 | struct rtable *rt = (struct rtable *)dst; |
1da177e4 LT |
754 | struct dst_entry *ret = dst; |
755 | ||
756 | if (rt) { | |
d11a4dc1 | 757 | if (dst->obsolete > 0) { |
1da177e4 LT |
758 | ip_rt_put(rt); |
759 | ret = NULL; | |
5943634f DM |
760 | } else if ((rt->rt_flags & RTCF_REDIRECTED) || |
761 | rt->dst.expires) { | |
89aef892 | 762 | ip_rt_put(rt); |
1da177e4 LT |
763 | ret = NULL; |
764 | } | |
765 | } | |
766 | return ret; | |
767 | } | |
768 | ||
769 | /* | |
770 | * Algorithm: | |
771 | * 1. The first ip_rt_redirect_number redirects are sent | |
772 | * with exponential backoff, then we stop sending them at all, | |
773 | * assuming that the host ignores our redirects. | |
774 | * 2. If we did not see packets requiring redirects | |
775 | * during ip_rt_redirect_silence, we assume that the host | |
776 | * forgot redirected route and start to send redirects again. | |
777 | * | |
778 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
779 | * in icmp.c. | |
780 | * | |
781 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
782 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
783 | */ | |
784 | ||
785 | void ip_rt_send_redirect(struct sk_buff *skb) | |
786 | { | |
511c3f92 | 787 | struct rtable *rt = skb_rtable(skb); |
30038fc6 | 788 | struct in_device *in_dev; |
92d86829 | 789 | struct inet_peer *peer; |
1d861aa4 | 790 | struct net *net; |
30038fc6 | 791 | int log_martians; |
1da177e4 | 792 | |
30038fc6 | 793 | rcu_read_lock(); |
d8d1f30b | 794 | in_dev = __in_dev_get_rcu(rt->dst.dev); |
30038fc6 ED |
795 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { |
796 | rcu_read_unlock(); | |
1da177e4 | 797 | return; |
30038fc6 ED |
798 | } |
799 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
800 | rcu_read_unlock(); | |
1da177e4 | 801 | |
1d861aa4 DM |
802 | net = dev_net(rt->dst.dev); |
803 | peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1); | |
92d86829 DM |
804 | if (!peer) { |
805 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
806 | return; | |
807 | } | |
808 | ||
1da177e4 LT |
809 | /* No redirected packets during ip_rt_redirect_silence; |
810 | * reset the algorithm. | |
811 | */ | |
92d86829 DM |
812 | if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) |
813 | peer->rate_tokens = 0; | |
1da177e4 LT |
814 | |
815 | /* Too many ignored redirects; do not send anything | |
d8d1f30b | 816 | * set dst.rate_last to the last seen redirected packet. |
1da177e4 | 817 | */ |
92d86829 DM |
818 | if (peer->rate_tokens >= ip_rt_redirect_number) { |
819 | peer->rate_last = jiffies; | |
1d861aa4 | 820 | goto out_put_peer; |
1da177e4 LT |
821 | } |
822 | ||
823 | /* Check for load limit; set rate_last to the latest sent | |
824 | * redirect. | |
825 | */ | |
92d86829 | 826 | if (peer->rate_tokens == 0 || |
14fb8a76 | 827 | time_after(jiffies, |
92d86829 DM |
828 | (peer->rate_last + |
829 | (ip_rt_redirect_load << peer->rate_tokens)))) { | |
1da177e4 | 830 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); |
92d86829 DM |
831 | peer->rate_last = jiffies; |
832 | ++peer->rate_tokens; | |
1da177e4 | 833 | #ifdef CONFIG_IP_ROUTE_VERBOSE |
30038fc6 | 834 | if (log_martians && |
e87cc472 JP |
835 | peer->rate_tokens == ip_rt_redirect_number) |
836 | net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", | |
92101b3b | 837 | &ip_hdr(skb)->saddr, inet_iif(skb), |
f1ce3062 | 838 | &ip_hdr(skb)->daddr, &rt->rt_gateway); |
1da177e4 LT |
839 | #endif |
840 | } | |
1d861aa4 DM |
841 | out_put_peer: |
842 | inet_putpeer(peer); | |
1da177e4 LT |
843 | } |
844 | ||
845 | static int ip_error(struct sk_buff *skb) | |
846 | { | |
251da413 | 847 | struct in_device *in_dev = __in_dev_get_rcu(skb->dev); |
511c3f92 | 848 | struct rtable *rt = skb_rtable(skb); |
92d86829 | 849 | struct inet_peer *peer; |
1da177e4 | 850 | unsigned long now; |
251da413 | 851 | struct net *net; |
92d86829 | 852 | bool send; |
1da177e4 LT |
853 | int code; |
854 | ||
251da413 DM |
855 | net = dev_net(rt->dst.dev); |
856 | if (!IN_DEV_FORWARD(in_dev)) { | |
857 | switch (rt->dst.error) { | |
858 | case EHOSTUNREACH: | |
859 | IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS); | |
860 | break; | |
861 | ||
862 | case ENETUNREACH: | |
863 | IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES); | |
864 | break; | |
865 | } | |
866 | goto out; | |
867 | } | |
868 | ||
d8d1f30b | 869 | switch (rt->dst.error) { |
4500ebf8 JP |
870 | case EINVAL: |
871 | default: | |
872 | goto out; | |
873 | case EHOSTUNREACH: | |
874 | code = ICMP_HOST_UNREACH; | |
875 | break; | |
876 | case ENETUNREACH: | |
877 | code = ICMP_NET_UNREACH; | |
251da413 | 878 | IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES); |
4500ebf8 JP |
879 | break; |
880 | case EACCES: | |
881 | code = ICMP_PKT_FILTERED; | |
882 | break; | |
1da177e4 LT |
883 | } |
884 | ||
1d861aa4 | 885 | peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1); |
92d86829 DM |
886 | |
887 | send = true; | |
888 | if (peer) { | |
889 | now = jiffies; | |
890 | peer->rate_tokens += now - peer->rate_last; | |
891 | if (peer->rate_tokens > ip_rt_error_burst) | |
892 | peer->rate_tokens = ip_rt_error_burst; | |
893 | peer->rate_last = now; | |
894 | if (peer->rate_tokens >= ip_rt_error_cost) | |
895 | peer->rate_tokens -= ip_rt_error_cost; | |
896 | else | |
897 | send = false; | |
1d861aa4 | 898 | inet_putpeer(peer); |
1da177e4 | 899 | } |
92d86829 DM |
900 | if (send) |
901 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1da177e4 LT |
902 | |
903 | out: kfree_skb(skb); | |
904 | return 0; | |
e905a9ed | 905 | } |
1da177e4 | 906 | |
d851c12b | 907 | static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu) |
1da177e4 | 908 | { |
d851c12b | 909 | struct dst_entry *dst = &rt->dst; |
4895c771 | 910 | struct fib_result res; |
2c8cec5c | 911 | |
7f92d334 SK |
912 | if (dst->dev->mtu < mtu) |
913 | return; | |
914 | ||
5943634f DM |
915 | if (mtu < ip_rt_min_pmtu) |
916 | mtu = ip_rt_min_pmtu; | |
2c8cec5c | 917 | |
d851c12b SK |
918 | if (!rt->rt_pmtu) { |
919 | dst->obsolete = DST_OBSOLETE_KILL; | |
920 | } else { | |
921 | rt->rt_pmtu = mtu; | |
922 | dst->expires = max(1UL, jiffies + ip_rt_mtu_expires); | |
923 | } | |
924 | ||
c5ae7d41 | 925 | rcu_read_lock(); |
d851c12b | 926 | if (fib_lookup(dev_net(dst->dev), fl4, &res) == 0) { |
4895c771 | 927 | struct fib_nh *nh = &FIB_RES_NH(res); |
4895c771 | 928 | |
aee06da6 JA |
929 | update_or_create_fnhe(nh, fl4->daddr, 0, mtu, |
930 | jiffies + ip_rt_mtu_expires); | |
4895c771 | 931 | } |
c5ae7d41 | 932 | rcu_read_unlock(); |
1da177e4 LT |
933 | } |
934 | ||
4895c771 DM |
935 | static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, |
936 | struct sk_buff *skb, u32 mtu) | |
937 | { | |
938 | struct rtable *rt = (struct rtable *) dst; | |
939 | struct flowi4 fl4; | |
940 | ||
941 | ip_rt_build_flow_key(&fl4, sk, skb); | |
d851c12b | 942 | __ip_rt_update_pmtu(rt, &fl4, mtu); |
4895c771 DM |
943 | } |
944 | ||
36393395 DM |
945 | void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, |
946 | int oif, u32 mark, u8 protocol, int flow_flags) | |
947 | { | |
4895c771 | 948 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
36393395 DM |
949 | struct flowi4 fl4; |
950 | struct rtable *rt; | |
951 | ||
4895c771 DM |
952 | __build_flow_key(&fl4, NULL, iph, oif, |
953 | RT_TOS(iph->tos), protocol, mark, flow_flags); | |
36393395 DM |
954 | rt = __ip_route_output_key(net, &fl4); |
955 | if (!IS_ERR(rt)) { | |
4895c771 | 956 | __ip_rt_update_pmtu(rt, &fl4, mtu); |
36393395 DM |
957 | ip_rt_put(rt); |
958 | } | |
959 | } | |
960 | EXPORT_SYMBOL_GPL(ipv4_update_pmtu); | |
961 | ||
962 | void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) | |
963 | { | |
4895c771 DM |
964 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
965 | struct flowi4 fl4; | |
966 | struct rtable *rt; | |
36393395 | 967 | |
4895c771 DM |
968 | __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0); |
969 | rt = __ip_route_output_key(sock_net(sk), &fl4); | |
970 | if (!IS_ERR(rt)) { | |
971 | __ip_rt_update_pmtu(rt, &fl4, mtu); | |
972 | ip_rt_put(rt); | |
973 | } | |
36393395 DM |
974 | } |
975 | EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu); | |
f39925db | 976 | |
b42597e2 DM |
977 | void ipv4_redirect(struct sk_buff *skb, struct net *net, |
978 | int oif, u32 mark, u8 protocol, int flow_flags) | |
979 | { | |
4895c771 | 980 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
b42597e2 DM |
981 | struct flowi4 fl4; |
982 | struct rtable *rt; | |
983 | ||
4895c771 DM |
984 | __build_flow_key(&fl4, NULL, iph, oif, |
985 | RT_TOS(iph->tos), protocol, mark, flow_flags); | |
b42597e2 DM |
986 | rt = __ip_route_output_key(net, &fl4); |
987 | if (!IS_ERR(rt)) { | |
ceb33206 | 988 | __ip_do_redirect(rt, skb, &fl4, false); |
b42597e2 DM |
989 | ip_rt_put(rt); |
990 | } | |
991 | } | |
992 | EXPORT_SYMBOL_GPL(ipv4_redirect); | |
993 | ||
994 | void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk) | |
995 | { | |
4895c771 DM |
996 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
997 | struct flowi4 fl4; | |
998 | struct rtable *rt; | |
b42597e2 | 999 | |
4895c771 DM |
1000 | __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0); |
1001 | rt = __ip_route_output_key(sock_net(sk), &fl4); | |
1002 | if (!IS_ERR(rt)) { | |
ceb33206 | 1003 | __ip_do_redirect(rt, skb, &fl4, false); |
4895c771 DM |
1004 | ip_rt_put(rt); |
1005 | } | |
b42597e2 DM |
1006 | } |
1007 | EXPORT_SYMBOL_GPL(ipv4_sk_redirect); | |
1008 | ||
efbc368d DM |
1009 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) |
1010 | { | |
1011 | struct rtable *rt = (struct rtable *) dst; | |
1012 | ||
ceb33206 DM |
1013 | /* All IPV4 dsts are created with ->obsolete set to the value |
1014 | * DST_OBSOLETE_FORCE_CHK which forces validation calls down | |
1015 | * into this function always. | |
1016 | * | |
1017 | * When a PMTU/redirect information update invalidates a | |
1018 | * route, this is indicated by setting obsolete to | |
1019 | * DST_OBSOLETE_KILL. | |
1020 | */ | |
1021 | if (dst->obsolete == DST_OBSOLETE_KILL || rt_is_expired(rt)) | |
efbc368d | 1022 | return NULL; |
d11a4dc1 | 1023 | return dst; |
1da177e4 LT |
1024 | } |
1025 | ||
1da177e4 LT |
1026 | static void ipv4_link_failure(struct sk_buff *skb) |
1027 | { | |
1028 | struct rtable *rt; | |
1029 | ||
1030 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1031 | ||
511c3f92 | 1032 | rt = skb_rtable(skb); |
5943634f DM |
1033 | if (rt) |
1034 | dst_set_expires(&rt->dst, 0); | |
1da177e4 LT |
1035 | } |
1036 | ||
1037 | static int ip_rt_bug(struct sk_buff *skb) | |
1038 | { | |
91df42be JP |
1039 | pr_debug("%s: %pI4 -> %pI4, %s\n", |
1040 | __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1041 | skb->dev ? skb->dev->name : "?"); | |
1da177e4 | 1042 | kfree_skb(skb); |
c378a9c0 | 1043 | WARN_ON(1); |
1da177e4 LT |
1044 | return 0; |
1045 | } | |
1046 | ||
1047 | /* | |
1048 | We do not cache source address of outgoing interface, | |
1049 | because it is used only by IP RR, TS and SRR options, | |
1050 | so that it out of fast path. | |
1051 | ||
1052 | BTW remember: "addr" is allowed to be not aligned | |
1053 | in IP options! | |
1054 | */ | |
1055 | ||
8e36360a | 1056 | void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) |
1da177e4 | 1057 | { |
a61ced5d | 1058 | __be32 src; |
1da177e4 | 1059 | |
c7537967 | 1060 | if (rt_is_output_route(rt)) |
c5be24ff | 1061 | src = ip_hdr(skb)->saddr; |
ebc0ffae | 1062 | else { |
8e36360a DM |
1063 | struct fib_result res; |
1064 | struct flowi4 fl4; | |
1065 | struct iphdr *iph; | |
1066 | ||
1067 | iph = ip_hdr(skb); | |
1068 | ||
1069 | memset(&fl4, 0, sizeof(fl4)); | |
1070 | fl4.daddr = iph->daddr; | |
1071 | fl4.saddr = iph->saddr; | |
b0fe4a31 | 1072 | fl4.flowi4_tos = RT_TOS(iph->tos); |
8e36360a DM |
1073 | fl4.flowi4_oif = rt->dst.dev->ifindex; |
1074 | fl4.flowi4_iif = skb->dev->ifindex; | |
1075 | fl4.flowi4_mark = skb->mark; | |
5e2b61f7 | 1076 | |
ebc0ffae | 1077 | rcu_read_lock(); |
68a5e3dd | 1078 | if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0) |
436c3b66 | 1079 | src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); |
ebc0ffae | 1080 | else |
f8126f1d DM |
1081 | src = inet_select_addr(rt->dst.dev, |
1082 | rt_nexthop(rt, iph->daddr), | |
1083 | RT_SCOPE_UNIVERSE); | |
ebc0ffae ED |
1084 | rcu_read_unlock(); |
1085 | } | |
1da177e4 LT |
1086 | memcpy(addr, &src, 4); |
1087 | } | |
1088 | ||
c7066f70 | 1089 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1090 | static void set_class_tag(struct rtable *rt, u32 tag) |
1091 | { | |
d8d1f30b CG |
1092 | if (!(rt->dst.tclassid & 0xFFFF)) |
1093 | rt->dst.tclassid |= tag & 0xFFFF; | |
1094 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1095 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1da177e4 LT |
1096 | } |
1097 | #endif | |
1098 | ||
0dbaee3b DM |
1099 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst) |
1100 | { | |
1101 | unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS); | |
1102 | ||
1103 | if (advmss == 0) { | |
1104 | advmss = max_t(unsigned int, dst->dev->mtu - 40, | |
1105 | ip_rt_min_advmss); | |
1106 | if (advmss > 65535 - 40) | |
1107 | advmss = 65535 - 40; | |
1108 | } | |
1109 | return advmss; | |
1110 | } | |
1111 | ||
ebb762f2 | 1112 | static unsigned int ipv4_mtu(const struct dst_entry *dst) |
d33e4553 | 1113 | { |
261663b0 | 1114 | const struct rtable *rt = (const struct rtable *) dst; |
5943634f DM |
1115 | unsigned int mtu = rt->rt_pmtu; |
1116 | ||
98d75c37 | 1117 | if (!mtu || time_after_eq(jiffies, rt->dst.expires)) |
5943634f | 1118 | mtu = dst_metric_raw(dst, RTAX_MTU); |
618f9bc7 | 1119 | |
261663b0 | 1120 | if (mtu && rt_is_output_route(rt)) |
618f9bc7 SK |
1121 | return mtu; |
1122 | ||
1123 | mtu = dst->dev->mtu; | |
d33e4553 DM |
1124 | |
1125 | if (unlikely(dst_metric_locked(dst, RTAX_MTU))) { | |
f8126f1d | 1126 | if (rt->rt_gateway && mtu > 576) |
d33e4553 DM |
1127 | mtu = 576; |
1128 | } | |
1129 | ||
1130 | if (mtu > IP_MAX_MTU) | |
1131 | mtu = IP_MAX_MTU; | |
1132 | ||
1133 | return mtu; | |
1134 | } | |
1135 | ||
f2bb4bed | 1136 | static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr) |
4895c771 DM |
1137 | { |
1138 | struct fnhe_hash_bucket *hash = nh->nh_exceptions; | |
1139 | struct fib_nh_exception *fnhe; | |
1140 | u32 hval; | |
1141 | ||
f2bb4bed DM |
1142 | if (!hash) |
1143 | return NULL; | |
1144 | ||
d3a25c98 | 1145 | hval = fnhe_hashfun(daddr); |
4895c771 DM |
1146 | |
1147 | for (fnhe = rcu_dereference(hash[hval].chain); fnhe; | |
1148 | fnhe = rcu_dereference(fnhe->fnhe_next)) { | |
f2bb4bed DM |
1149 | if (fnhe->fnhe_daddr == daddr) |
1150 | return fnhe; | |
1151 | } | |
1152 | return NULL; | |
1153 | } | |
aee06da6 | 1154 | |
caacf05e | 1155 | static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe, |
f2bb4bed DM |
1156 | __be32 daddr) |
1157 | { | |
caacf05e DM |
1158 | bool ret = false; |
1159 | ||
c5038a83 | 1160 | spin_lock_bh(&fnhe_lock); |
f2bb4bed | 1161 | |
c5038a83 DM |
1162 | if (daddr == fnhe->fnhe_daddr) { |
1163 | struct rtable *orig; | |
f2bb4bed | 1164 | |
c5038a83 DM |
1165 | if (fnhe->fnhe_pmtu) { |
1166 | unsigned long expires = fnhe->fnhe_expires; | |
1167 | unsigned long diff = expires - jiffies; | |
1168 | ||
1169 | if (time_before(jiffies, expires)) { | |
1170 | rt->rt_pmtu = fnhe->fnhe_pmtu; | |
1171 | dst_set_expires(&rt->dst, diff); | |
1172 | } | |
1173 | } | |
1174 | if (fnhe->fnhe_gw) { | |
1175 | rt->rt_flags |= RTCF_REDIRECTED; | |
1176 | rt->rt_gateway = fnhe->fnhe_gw; | |
ceb33206 | 1177 | } |
f2bb4bed | 1178 | |
c5038a83 DM |
1179 | orig = rcu_dereference(fnhe->fnhe_rth); |
1180 | rcu_assign_pointer(fnhe->fnhe_rth, rt); | |
1181 | if (orig) | |
1182 | rt_free(orig); | |
1183 | ||
1184 | fnhe->fnhe_stamp = jiffies; | |
caacf05e | 1185 | ret = true; |
c5038a83 DM |
1186 | } else { |
1187 | /* Routes we intend to cache in nexthop exception have | |
1188 | * the DST_NOCACHE bit clear. However, if we are | |
1189 | * unsuccessful at storing this route into the cache | |
1190 | * we really need to set it. | |
1191 | */ | |
1192 | rt->dst.flags |= DST_NOCACHE; | |
1193 | } | |
1194 | spin_unlock_bh(&fnhe_lock); | |
caacf05e DM |
1195 | |
1196 | return ret; | |
54764bb6 ED |
1197 | } |
1198 | ||
caacf05e | 1199 | static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt) |
f2bb4bed | 1200 | { |
d26b3a7c | 1201 | struct rtable *orig, *prev, **p; |
caacf05e | 1202 | bool ret = true; |
f2bb4bed | 1203 | |
d26b3a7c | 1204 | if (rt_is_input_route(rt)) { |
54764bb6 | 1205 | p = (struct rtable **)&nh->nh_rth_input; |
d26b3a7c ED |
1206 | } else { |
1207 | if (!nh->nh_pcpu_rth_output) | |
1208 | goto nocache; | |
1209 | p = (struct rtable **)__this_cpu_ptr(nh->nh_pcpu_rth_output); | |
1210 | } | |
f2bb4bed DM |
1211 | orig = *p; |
1212 | ||
1213 | prev = cmpxchg(p, orig, rt); | |
1214 | if (prev == orig) { | |
f2bb4bed | 1215 | if (orig) |
54764bb6 | 1216 | rt_free(orig); |
c6cffba4 | 1217 | } else { |
54764bb6 ED |
1218 | /* Routes we intend to cache in the FIB nexthop have |
1219 | * the DST_NOCACHE bit clear. However, if we are | |
1220 | * unsuccessful at storing this route into the cache | |
1221 | * we really need to set it. | |
1222 | */ | |
d26b3a7c | 1223 | nocache: |
54764bb6 | 1224 | rt->dst.flags |= DST_NOCACHE; |
caacf05e DM |
1225 | ret = false; |
1226 | } | |
1227 | ||
1228 | return ret; | |
1229 | } | |
1230 | ||
1231 | static DEFINE_SPINLOCK(rt_uncached_lock); | |
1232 | static LIST_HEAD(rt_uncached_list); | |
1233 | ||
1234 | static void rt_add_uncached_list(struct rtable *rt) | |
1235 | { | |
1236 | spin_lock_bh(&rt_uncached_lock); | |
1237 | list_add_tail(&rt->rt_uncached, &rt_uncached_list); | |
1238 | spin_unlock_bh(&rt_uncached_lock); | |
1239 | } | |
1240 | ||
1241 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1242 | { | |
1243 | struct rtable *rt = (struct rtable *) dst; | |
1244 | ||
78df76a0 | 1245 | if (!list_empty(&rt->rt_uncached)) { |
caacf05e DM |
1246 | spin_lock_bh(&rt_uncached_lock); |
1247 | list_del(&rt->rt_uncached); | |
1248 | spin_unlock_bh(&rt_uncached_lock); | |
1249 | } | |
1250 | } | |
1251 | ||
1252 | void rt_flush_dev(struct net_device *dev) | |
1253 | { | |
1254 | if (!list_empty(&rt_uncached_list)) { | |
1255 | struct net *net = dev_net(dev); | |
1256 | struct rtable *rt; | |
1257 | ||
1258 | spin_lock_bh(&rt_uncached_lock); | |
1259 | list_for_each_entry(rt, &rt_uncached_list, rt_uncached) { | |
1260 | if (rt->dst.dev != dev) | |
1261 | continue; | |
1262 | rt->dst.dev = net->loopback_dev; | |
1263 | dev_hold(rt->dst.dev); | |
1264 | dev_put(dev); | |
1265 | } | |
1266 | spin_unlock_bh(&rt_uncached_lock); | |
4895c771 DM |
1267 | } |
1268 | } | |
1269 | ||
4331debc | 1270 | static bool rt_cache_valid(const struct rtable *rt) |
d2d68ba9 | 1271 | { |
4331debc ED |
1272 | return rt && |
1273 | rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK && | |
1274 | !rt_is_expired(rt); | |
d2d68ba9 DM |
1275 | } |
1276 | ||
f2bb4bed | 1277 | static void rt_set_nexthop(struct rtable *rt, __be32 daddr, |
5e2b61f7 | 1278 | const struct fib_result *res, |
f2bb4bed | 1279 | struct fib_nh_exception *fnhe, |
982721f3 | 1280 | struct fib_info *fi, u16 type, u32 itag) |
1da177e4 | 1281 | { |
caacf05e DM |
1282 | bool cached = false; |
1283 | ||
1da177e4 | 1284 | if (fi) { |
4895c771 DM |
1285 | struct fib_nh *nh = &FIB_RES_NH(*res); |
1286 | ||
1287 | if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) | |
1288 | rt->rt_gateway = nh->nh_gw; | |
2860583f | 1289 | dst_init_metrics(&rt->dst, fi->fib_metrics, true); |
c7066f70 | 1290 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f2bb4bed | 1291 | rt->dst.tclassid = nh->nh_tclassid; |
1da177e4 | 1292 | #endif |
c5038a83 | 1293 | if (unlikely(fnhe)) |
caacf05e | 1294 | cached = rt_bind_exception(rt, fnhe, daddr); |
c5038a83 | 1295 | else if (!(rt->dst.flags & DST_NOCACHE)) |
caacf05e | 1296 | cached = rt_cache_route(nh, rt); |
d33e4553 | 1297 | } |
caacf05e DM |
1298 | if (unlikely(!cached)) |
1299 | rt_add_uncached_list(rt); | |
defb3519 | 1300 | |
c7066f70 | 1301 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 | 1302 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
85b91b03 | 1303 | set_class_tag(rt, res->tclassid); |
1da177e4 LT |
1304 | #endif |
1305 | set_class_tag(rt, itag); | |
1306 | #endif | |
1da177e4 LT |
1307 | } |
1308 | ||
5c1e6aa3 | 1309 | static struct rtable *rt_dst_alloc(struct net_device *dev, |
f2bb4bed | 1310 | bool nopolicy, bool noxfrm, bool will_cache) |
0c4dcd58 | 1311 | { |
f5b0a874 | 1312 | return dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK, |
c6cffba4 | 1313 | (will_cache ? 0 : (DST_HOST | DST_NOCACHE)) | |
5c1e6aa3 DM |
1314 | (nopolicy ? DST_NOPOLICY : 0) | |
1315 | (noxfrm ? DST_NOXFRM : 0)); | |
0c4dcd58 DM |
1316 | } |
1317 | ||
96d36220 | 1318 | /* called in rcu_read_lock() section */ |
9e12bb22 | 1319 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1da177e4 LT |
1320 | u8 tos, struct net_device *dev, int our) |
1321 | { | |
1da177e4 | 1322 | struct rtable *rth; |
96d36220 | 1323 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 1324 | u32 itag = 0; |
b5f7e755 | 1325 | int err; |
1da177e4 LT |
1326 | |
1327 | /* Primary sanity checks. */ | |
1328 | ||
1329 | if (in_dev == NULL) | |
1330 | return -EINVAL; | |
1331 | ||
1e637c74 | 1332 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
d0daebc3 | 1333 | skb->protocol != htons(ETH_P_IP)) |
1da177e4 LT |
1334 | goto e_inval; |
1335 | ||
d0daebc3 TG |
1336 | if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) |
1337 | if (ipv4_is_loopback(saddr)) | |
1338 | goto e_inval; | |
1339 | ||
f97c1e0c JP |
1340 | if (ipv4_is_zeronet(saddr)) { |
1341 | if (!ipv4_is_local_multicast(daddr)) | |
1da177e4 | 1342 | goto e_inval; |
b5f7e755 | 1343 | } else { |
9e56e380 DM |
1344 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, |
1345 | in_dev, &itag); | |
b5f7e755 ED |
1346 | if (err < 0) |
1347 | goto e_err; | |
1348 | } | |
4e7b2f14 | 1349 | rth = rt_dst_alloc(dev_net(dev)->loopback_dev, |
f2bb4bed | 1350 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false); |
1da177e4 LT |
1351 | if (!rth) |
1352 | goto e_nobufs; | |
1353 | ||
cf911662 DM |
1354 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1355 | rth->dst.tclassid = itag; | |
1356 | #endif | |
d8d1f30b | 1357 | rth->dst.output = ip_rt_bug; |
1da177e4 | 1358 | |
cf911662 DM |
1359 | rth->rt_genid = rt_genid(dev_net(dev)); |
1360 | rth->rt_flags = RTCF_MULTICAST; | |
1361 | rth->rt_type = RTN_MULTICAST; | |
9917e1e8 | 1362 | rth->rt_is_input= 1; |
13378cad | 1363 | rth->rt_iif = 0; |
5943634f | 1364 | rth->rt_pmtu = 0; |
f8126f1d | 1365 | rth->rt_gateway = 0; |
caacf05e | 1366 | INIT_LIST_HEAD(&rth->rt_uncached); |
1da177e4 | 1367 | if (our) { |
d8d1f30b | 1368 | rth->dst.input= ip_local_deliver; |
1da177e4 LT |
1369 | rth->rt_flags |= RTCF_LOCAL; |
1370 | } | |
1371 | ||
1372 | #ifdef CONFIG_IP_MROUTE | |
f97c1e0c | 1373 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) |
d8d1f30b | 1374 | rth->dst.input = ip_mr_input; |
1da177e4 LT |
1375 | #endif |
1376 | RT_CACHE_STAT_INC(in_slow_mc); | |
1377 | ||
89aef892 DM |
1378 | skb_dst_set(skb, &rth->dst); |
1379 | return 0; | |
1da177e4 LT |
1380 | |
1381 | e_nobufs: | |
1da177e4 | 1382 | return -ENOBUFS; |
1da177e4 | 1383 | e_inval: |
96d36220 | 1384 | return -EINVAL; |
b5f7e755 | 1385 | e_err: |
b5f7e755 | 1386 | return err; |
1da177e4 LT |
1387 | } |
1388 | ||
1389 | ||
1390 | static void ip_handle_martian_source(struct net_device *dev, | |
1391 | struct in_device *in_dev, | |
1392 | struct sk_buff *skb, | |
9e12bb22 AV |
1393 | __be32 daddr, |
1394 | __be32 saddr) | |
1da177e4 LT |
1395 | { |
1396 | RT_CACHE_STAT_INC(in_martian_src); | |
1397 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1398 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
1399 | /* | |
1400 | * RFC1812 recommendation, if source is martian, | |
1401 | * the only hint is MAC header. | |
1402 | */ | |
058bd4d2 | 1403 | pr_warn("martian source %pI4 from %pI4, on dev %s\n", |
673d57e7 | 1404 | &daddr, &saddr, dev->name); |
98e399f8 | 1405 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { |
058bd4d2 JP |
1406 | print_hex_dump(KERN_WARNING, "ll header: ", |
1407 | DUMP_PREFIX_OFFSET, 16, 1, | |
1408 | skb_mac_header(skb), | |
1409 | dev->hard_header_len, true); | |
1da177e4 LT |
1410 | } |
1411 | } | |
1412 | #endif | |
1413 | } | |
1414 | ||
47360228 | 1415 | /* called in rcu_read_lock() section */ |
5969f71d | 1416 | static int __mkroute_input(struct sk_buff *skb, |
982721f3 | 1417 | const struct fib_result *res, |
5969f71d | 1418 | struct in_device *in_dev, |
c6cffba4 | 1419 | __be32 daddr, __be32 saddr, u32 tos) |
1da177e4 | 1420 | { |
1da177e4 LT |
1421 | struct rtable *rth; |
1422 | int err; | |
1423 | struct in_device *out_dev; | |
47360228 | 1424 | unsigned int flags = 0; |
d2d68ba9 | 1425 | bool do_cache; |
d9c9df8c | 1426 | u32 itag; |
1da177e4 LT |
1427 | |
1428 | /* get a working reference to the output device */ | |
47360228 | 1429 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); |
1da177e4 | 1430 | if (out_dev == NULL) { |
e87cc472 | 1431 | net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n"); |
1da177e4 LT |
1432 | return -EINVAL; |
1433 | } | |
1434 | ||
1435 | ||
5c04c819 | 1436 | err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), |
9e56e380 | 1437 | in_dev->dev, in_dev, &itag); |
1da177e4 | 1438 | if (err < 0) { |
e905a9ed | 1439 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, |
1da177e4 | 1440 | saddr); |
e905a9ed | 1441 | |
1da177e4 LT |
1442 | goto cleanup; |
1443 | } | |
1444 | ||
51b77cae | 1445 | if (out_dev == in_dev && err && |
1da177e4 LT |
1446 | (IN_DEV_SHARED_MEDIA(out_dev) || |
1447 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
1448 | flags |= RTCF_DOREDIRECT; | |
1449 | ||
1450 | if (skb->protocol != htons(ETH_P_IP)) { | |
1451 | /* Not IP (i.e. ARP). Do not create route, if it is | |
1452 | * invalid for proxy arp. DNAT routes are always valid. | |
65324144 JDB |
1453 | * |
1454 | * Proxy arp feature have been extended to allow, ARP | |
1455 | * replies back to the same interface, to support | |
1456 | * Private VLAN switch technologies. See arp.c. | |
1da177e4 | 1457 | */ |
65324144 JDB |
1458 | if (out_dev == in_dev && |
1459 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
1da177e4 LT |
1460 | err = -EINVAL; |
1461 | goto cleanup; | |
1462 | } | |
1463 | } | |
1464 | ||
d2d68ba9 DM |
1465 | do_cache = false; |
1466 | if (res->fi) { | |
fe3edf45 | 1467 | if (!itag) { |
54764bb6 | 1468 | rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input); |
d2d68ba9 | 1469 | if (rt_cache_valid(rth)) { |
c6cffba4 | 1470 | skb_dst_set_noref(skb, &rth->dst); |
d2d68ba9 DM |
1471 | goto out; |
1472 | } | |
1473 | do_cache = true; | |
1474 | } | |
1475 | } | |
f2bb4bed | 1476 | |
5c1e6aa3 DM |
1477 | rth = rt_dst_alloc(out_dev->dev, |
1478 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
d2d68ba9 | 1479 | IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache); |
1da177e4 LT |
1480 | if (!rth) { |
1481 | err = -ENOBUFS; | |
1482 | goto cleanup; | |
1483 | } | |
1484 | ||
cf911662 DM |
1485 | rth->rt_genid = rt_genid(dev_net(rth->dst.dev)); |
1486 | rth->rt_flags = flags; | |
1487 | rth->rt_type = res->type; | |
9917e1e8 | 1488 | rth->rt_is_input = 1; |
13378cad | 1489 | rth->rt_iif = 0; |
5943634f | 1490 | rth->rt_pmtu = 0; |
f8126f1d | 1491 | rth->rt_gateway = 0; |
caacf05e | 1492 | INIT_LIST_HEAD(&rth->rt_uncached); |
1da177e4 | 1493 | |
d8d1f30b CG |
1494 | rth->dst.input = ip_forward; |
1495 | rth->dst.output = ip_output; | |
1da177e4 | 1496 | |
d2d68ba9 | 1497 | rt_set_nexthop(rth, daddr, res, NULL, res->fi, res->type, itag); |
c6cffba4 | 1498 | skb_dst_set(skb, &rth->dst); |
d2d68ba9 | 1499 | out: |
1da177e4 LT |
1500 | err = 0; |
1501 | cleanup: | |
1da177e4 | 1502 | return err; |
e905a9ed | 1503 | } |
1da177e4 | 1504 | |
5969f71d SH |
1505 | static int ip_mkroute_input(struct sk_buff *skb, |
1506 | struct fib_result *res, | |
68a5e3dd | 1507 | const struct flowi4 *fl4, |
5969f71d SH |
1508 | struct in_device *in_dev, |
1509 | __be32 daddr, __be32 saddr, u32 tos) | |
1da177e4 | 1510 | { |
1da177e4 | 1511 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
ff3fccb3 | 1512 | if (res->fi && res->fi->fib_nhs > 1) |
1b7fe593 | 1513 | fib_select_multipath(res); |
1da177e4 LT |
1514 | #endif |
1515 | ||
1516 | /* create a routing cache entry */ | |
c6cffba4 | 1517 | return __mkroute_input(skb, res, in_dev, daddr, saddr, tos); |
1da177e4 LT |
1518 | } |
1519 | ||
1da177e4 LT |
1520 | /* |
1521 | * NOTE. We drop all the packets that has local source | |
1522 | * addresses, because every properly looped back packet | |
1523 | * must have correct destination already attached by output routine. | |
1524 | * | |
1525 | * Such approach solves two big problems: | |
1526 | * 1. Not simplex devices are handled properly. | |
1527 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
ebc0ffae | 1528 | * called with rcu_read_lock() |
1da177e4 LT |
1529 | */ |
1530 | ||
9e12bb22 | 1531 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
c10237e0 | 1532 | u8 tos, struct net_device *dev) |
1da177e4 LT |
1533 | { |
1534 | struct fib_result res; | |
96d36220 | 1535 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
68a5e3dd | 1536 | struct flowi4 fl4; |
95c96174 | 1537 | unsigned int flags = 0; |
1da177e4 | 1538 | u32 itag = 0; |
95c96174 | 1539 | struct rtable *rth; |
1da177e4 | 1540 | int err = -EINVAL; |
5e73ea1a | 1541 | struct net *net = dev_net(dev); |
d2d68ba9 | 1542 | bool do_cache; |
1da177e4 LT |
1543 | |
1544 | /* IP on this device is disabled. */ | |
1545 | ||
1546 | if (!in_dev) | |
1547 | goto out; | |
1548 | ||
1549 | /* Check for the most weird martians, which can be not detected | |
1550 | by fib_lookup. | |
1551 | */ | |
1552 | ||
d0daebc3 | 1553 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) |
1da177e4 LT |
1554 | goto martian_source; |
1555 | ||
d2d68ba9 | 1556 | res.fi = NULL; |
27a954bd | 1557 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) |
1da177e4 LT |
1558 | goto brd_input; |
1559 | ||
1560 | /* Accept zero addresses only to limited broadcast; | |
1561 | * I even do not know to fix it or not. Waiting for complains :-) | |
1562 | */ | |
f97c1e0c | 1563 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
1564 | goto martian_source; |
1565 | ||
d0daebc3 | 1566 | if (ipv4_is_zeronet(daddr)) |
1da177e4 LT |
1567 | goto martian_destination; |
1568 | ||
9eb43e76 ED |
1569 | /* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(), |
1570 | * and call it once if daddr or/and saddr are loopback addresses | |
1571 | */ | |
1572 | if (ipv4_is_loopback(daddr)) { | |
1573 | if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) | |
d0daebc3 | 1574 | goto martian_destination; |
9eb43e76 ED |
1575 | } else if (ipv4_is_loopback(saddr)) { |
1576 | if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) | |
d0daebc3 TG |
1577 | goto martian_source; |
1578 | } | |
1579 | ||
1da177e4 LT |
1580 | /* |
1581 | * Now we are ready to route packet. | |
1582 | */ | |
68a5e3dd DM |
1583 | fl4.flowi4_oif = 0; |
1584 | fl4.flowi4_iif = dev->ifindex; | |
1585 | fl4.flowi4_mark = skb->mark; | |
1586 | fl4.flowi4_tos = tos; | |
1587 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
1588 | fl4.daddr = daddr; | |
1589 | fl4.saddr = saddr; | |
1590 | err = fib_lookup(net, &fl4, &res); | |
251da413 | 1591 | if (err != 0) |
1da177e4 | 1592 | goto no_route; |
1da177e4 LT |
1593 | |
1594 | RT_CACHE_STAT_INC(in_slow_tot); | |
1595 | ||
1596 | if (res.type == RTN_BROADCAST) | |
1597 | goto brd_input; | |
1598 | ||
1599 | if (res.type == RTN_LOCAL) { | |
5c04c819 | 1600 | err = fib_validate_source(skb, saddr, daddr, tos, |
1fb9489b | 1601 | LOOPBACK_IFINDEX, |
9e56e380 | 1602 | dev, in_dev, &itag); |
b5f7e755 ED |
1603 | if (err < 0) |
1604 | goto martian_source_keep_err; | |
1da177e4 LT |
1605 | goto local_input; |
1606 | } | |
1607 | ||
1608 | if (!IN_DEV_FORWARD(in_dev)) | |
251da413 | 1609 | goto no_route; |
1da177e4 LT |
1610 | if (res.type != RTN_UNICAST) |
1611 | goto martian_destination; | |
1612 | ||
68a5e3dd | 1613 | err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos); |
1da177e4 LT |
1614 | out: return err; |
1615 | ||
1616 | brd_input: | |
1617 | if (skb->protocol != htons(ETH_P_IP)) | |
1618 | goto e_inval; | |
1619 | ||
41347dcd | 1620 | if (!ipv4_is_zeronet(saddr)) { |
9e56e380 DM |
1621 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, |
1622 | in_dev, &itag); | |
1da177e4 | 1623 | if (err < 0) |
b5f7e755 | 1624 | goto martian_source_keep_err; |
1da177e4 LT |
1625 | } |
1626 | flags |= RTCF_BROADCAST; | |
1627 | res.type = RTN_BROADCAST; | |
1628 | RT_CACHE_STAT_INC(in_brd); | |
1629 | ||
1630 | local_input: | |
d2d68ba9 DM |
1631 | do_cache = false; |
1632 | if (res.fi) { | |
fe3edf45 | 1633 | if (!itag) { |
54764bb6 | 1634 | rth = rcu_dereference(FIB_RES_NH(res).nh_rth_input); |
d2d68ba9 | 1635 | if (rt_cache_valid(rth)) { |
c6cffba4 DM |
1636 | skb_dst_set_noref(skb, &rth->dst); |
1637 | err = 0; | |
1638 | goto out; | |
d2d68ba9 DM |
1639 | } |
1640 | do_cache = true; | |
1641 | } | |
1642 | } | |
1643 | ||
5c1e6aa3 | 1644 | rth = rt_dst_alloc(net->loopback_dev, |
d2d68ba9 | 1645 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache); |
1da177e4 LT |
1646 | if (!rth) |
1647 | goto e_nobufs; | |
1648 | ||
cf911662 | 1649 | rth->dst.input= ip_local_deliver; |
d8d1f30b | 1650 | rth->dst.output= ip_rt_bug; |
cf911662 DM |
1651 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1652 | rth->dst.tclassid = itag; | |
1653 | #endif | |
1da177e4 | 1654 | |
cf911662 DM |
1655 | rth->rt_genid = rt_genid(net); |
1656 | rth->rt_flags = flags|RTCF_LOCAL; | |
1657 | rth->rt_type = res.type; | |
9917e1e8 | 1658 | rth->rt_is_input = 1; |
13378cad | 1659 | rth->rt_iif = 0; |
5943634f | 1660 | rth->rt_pmtu = 0; |
f8126f1d | 1661 | rth->rt_gateway = 0; |
caacf05e | 1662 | INIT_LIST_HEAD(&rth->rt_uncached); |
1da177e4 | 1663 | if (res.type == RTN_UNREACHABLE) { |
d8d1f30b CG |
1664 | rth->dst.input= ip_error; |
1665 | rth->dst.error= -err; | |
1da177e4 LT |
1666 | rth->rt_flags &= ~RTCF_LOCAL; |
1667 | } | |
d2d68ba9 DM |
1668 | if (do_cache) |
1669 | rt_cache_route(&FIB_RES_NH(res), rth); | |
89aef892 | 1670 | skb_dst_set(skb, &rth->dst); |
b23dd4fe | 1671 | err = 0; |
ebc0ffae | 1672 | goto out; |
1da177e4 LT |
1673 | |
1674 | no_route: | |
1675 | RT_CACHE_STAT_INC(in_no_route); | |
1da177e4 | 1676 | res.type = RTN_UNREACHABLE; |
7f53878d MC |
1677 | if (err == -ESRCH) |
1678 | err = -ENETUNREACH; | |
1da177e4 LT |
1679 | goto local_input; |
1680 | ||
1681 | /* | |
1682 | * Do not cache martian addresses: they should be logged (RFC1812) | |
1683 | */ | |
1684 | martian_destination: | |
1685 | RT_CACHE_STAT_INC(in_martian_dst); | |
1686 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
e87cc472 JP |
1687 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
1688 | net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n", | |
1689 | &daddr, &saddr, dev->name); | |
1da177e4 | 1690 | #endif |
2c2910a4 | 1691 | |
1da177e4 LT |
1692 | e_inval: |
1693 | err = -EINVAL; | |
ebc0ffae | 1694 | goto out; |
1da177e4 LT |
1695 | |
1696 | e_nobufs: | |
1697 | err = -ENOBUFS; | |
ebc0ffae | 1698 | goto out; |
1da177e4 LT |
1699 | |
1700 | martian_source: | |
b5f7e755 ED |
1701 | err = -EINVAL; |
1702 | martian_source_keep_err: | |
1da177e4 | 1703 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); |
ebc0ffae | 1704 | goto out; |
1da177e4 LT |
1705 | } |
1706 | ||
c6cffba4 DM |
1707 | int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1708 | u8 tos, struct net_device *dev) | |
1da177e4 | 1709 | { |
96d36220 | 1710 | int res; |
1da177e4 | 1711 | |
96d36220 ED |
1712 | rcu_read_lock(); |
1713 | ||
1da177e4 LT |
1714 | /* Multicast recognition logic is moved from route cache to here. |
1715 | The problem was that too many Ethernet cards have broken/missing | |
1716 | hardware multicast filters :-( As result the host on multicasting | |
1717 | network acquires a lot of useless route cache entries, sort of | |
1718 | SDR messages from all the world. Now we try to get rid of them. | |
1719 | Really, provided software IP multicast filter is organized | |
1720 | reasonably (at least, hashed), it does not result in a slowdown | |
1721 | comparing with route cache reject entries. | |
1722 | Note, that multicast routers are not affected, because | |
1723 | route cache entry is created eventually. | |
1724 | */ | |
f97c1e0c | 1725 | if (ipv4_is_multicast(daddr)) { |
96d36220 | 1726 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4 | 1727 | |
96d36220 | 1728 | if (in_dev) { |
dbdd9a52 DM |
1729 | int our = ip_check_mc_rcu(in_dev, daddr, saddr, |
1730 | ip_hdr(skb)->protocol); | |
1da177e4 LT |
1731 | if (our |
1732 | #ifdef CONFIG_IP_MROUTE | |
9d4fb27d JP |
1733 | || |
1734 | (!ipv4_is_local_multicast(daddr) && | |
1735 | IN_DEV_MFORWARD(in_dev)) | |
1da177e4 | 1736 | #endif |
9d4fb27d | 1737 | ) { |
96d36220 ED |
1738 | int res = ip_route_input_mc(skb, daddr, saddr, |
1739 | tos, dev, our); | |
1da177e4 | 1740 | rcu_read_unlock(); |
96d36220 | 1741 | return res; |
1da177e4 LT |
1742 | } |
1743 | } | |
1744 | rcu_read_unlock(); | |
1745 | return -EINVAL; | |
1746 | } | |
c10237e0 | 1747 | res = ip_route_input_slow(skb, daddr, saddr, tos, dev); |
96d36220 ED |
1748 | rcu_read_unlock(); |
1749 | return res; | |
1da177e4 | 1750 | } |
c6cffba4 | 1751 | EXPORT_SYMBOL(ip_route_input_noref); |
1da177e4 | 1752 | |
ebc0ffae | 1753 | /* called with rcu_read_lock() */ |
982721f3 | 1754 | static struct rtable *__mkroute_output(const struct fib_result *res, |
1a00fee4 | 1755 | const struct flowi4 *fl4, int orig_oif, |
f61759e6 | 1756 | struct net_device *dev_out, |
5ada5527 | 1757 | unsigned int flags) |
1da177e4 | 1758 | { |
982721f3 | 1759 | struct fib_info *fi = res->fi; |
f2bb4bed | 1760 | struct fib_nh_exception *fnhe; |
5ada5527 | 1761 | struct in_device *in_dev; |
982721f3 | 1762 | u16 type = res->type; |
5ada5527 | 1763 | struct rtable *rth; |
1da177e4 | 1764 | |
d0daebc3 TG |
1765 | in_dev = __in_dev_get_rcu(dev_out); |
1766 | if (!in_dev) | |
5ada5527 | 1767 | return ERR_PTR(-EINVAL); |
1da177e4 | 1768 | |
d0daebc3 TG |
1769 | if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) |
1770 | if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) | |
1771 | return ERR_PTR(-EINVAL); | |
1772 | ||
68a5e3dd | 1773 | if (ipv4_is_lbcast(fl4->daddr)) |
982721f3 | 1774 | type = RTN_BROADCAST; |
68a5e3dd | 1775 | else if (ipv4_is_multicast(fl4->daddr)) |
982721f3 | 1776 | type = RTN_MULTICAST; |
68a5e3dd | 1777 | else if (ipv4_is_zeronet(fl4->daddr)) |
5ada5527 | 1778 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
1779 | |
1780 | if (dev_out->flags & IFF_LOOPBACK) | |
1781 | flags |= RTCF_LOCAL; | |
1782 | ||
982721f3 | 1783 | if (type == RTN_BROADCAST) { |
1da177e4 | 1784 | flags |= RTCF_BROADCAST | RTCF_LOCAL; |
982721f3 DM |
1785 | fi = NULL; |
1786 | } else if (type == RTN_MULTICAST) { | |
dd28d1a0 | 1787 | flags |= RTCF_MULTICAST | RTCF_LOCAL; |
813b3b5d DM |
1788 | if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, |
1789 | fl4->flowi4_proto)) | |
1da177e4 LT |
1790 | flags &= ~RTCF_LOCAL; |
1791 | /* If multicast route do not exist use | |
dd28d1a0 ED |
1792 | * default one, but do not gateway in this case. |
1793 | * Yes, it is hack. | |
1da177e4 | 1794 | */ |
982721f3 DM |
1795 | if (fi && res->prefixlen < 4) |
1796 | fi = NULL; | |
1da177e4 LT |
1797 | } |
1798 | ||
f2bb4bed DM |
1799 | fnhe = NULL; |
1800 | if (fi) { | |
c5038a83 | 1801 | struct rtable __rcu **prth; |
d26b3a7c | 1802 | |
c5038a83 DM |
1803 | fnhe = find_exception(&FIB_RES_NH(*res), fl4->daddr); |
1804 | if (fnhe) | |
1805 | prth = &fnhe->fnhe_rth; | |
1806 | else | |
d26b3a7c | 1807 | prth = __this_cpu_ptr(FIB_RES_NH(*res).nh_pcpu_rth_output); |
c5038a83 DM |
1808 | rth = rcu_dereference(*prth); |
1809 | if (rt_cache_valid(rth)) { | |
1810 | dst_hold(&rth->dst); | |
1811 | return rth; | |
f2bb4bed DM |
1812 | } |
1813 | } | |
5c1e6aa3 DM |
1814 | rth = rt_dst_alloc(dev_out, |
1815 | IN_DEV_CONF_GET(in_dev, NOPOLICY), | |
f2bb4bed | 1816 | IN_DEV_CONF_GET(in_dev, NOXFRM), |
c5038a83 | 1817 | fi); |
8391d07b | 1818 | if (!rth) |
5ada5527 | 1819 | return ERR_PTR(-ENOBUFS); |
8391d07b | 1820 | |
cf911662 DM |
1821 | rth->dst.output = ip_output; |
1822 | ||
cf911662 DM |
1823 | rth->rt_genid = rt_genid(dev_net(dev_out)); |
1824 | rth->rt_flags = flags; | |
1825 | rth->rt_type = type; | |
9917e1e8 | 1826 | rth->rt_is_input = 0; |
13378cad | 1827 | rth->rt_iif = orig_oif ? : 0; |
5943634f | 1828 | rth->rt_pmtu = 0; |
f8126f1d | 1829 | rth->rt_gateway = 0; |
caacf05e | 1830 | INIT_LIST_HEAD(&rth->rt_uncached); |
1da177e4 LT |
1831 | |
1832 | RT_CACHE_STAT_INC(out_slow_tot); | |
1833 | ||
41347dcd | 1834 | if (flags & RTCF_LOCAL) |
d8d1f30b | 1835 | rth->dst.input = ip_local_deliver; |
1da177e4 | 1836 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
e905a9ed | 1837 | if (flags & RTCF_LOCAL && |
1da177e4 | 1838 | !(dev_out->flags & IFF_LOOPBACK)) { |
d8d1f30b | 1839 | rth->dst.output = ip_mc_output; |
1da177e4 LT |
1840 | RT_CACHE_STAT_INC(out_slow_mc); |
1841 | } | |
1842 | #ifdef CONFIG_IP_MROUTE | |
982721f3 | 1843 | if (type == RTN_MULTICAST) { |
1da177e4 | 1844 | if (IN_DEV_MFORWARD(in_dev) && |
813b3b5d | 1845 | !ipv4_is_local_multicast(fl4->daddr)) { |
d8d1f30b CG |
1846 | rth->dst.input = ip_mr_input; |
1847 | rth->dst.output = ip_mc_output; | |
1da177e4 LT |
1848 | } |
1849 | } | |
1850 | #endif | |
1851 | } | |
1852 | ||
f2bb4bed | 1853 | rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0); |
1da177e4 | 1854 | |
5ada5527 | 1855 | return rth; |
1da177e4 LT |
1856 | } |
1857 | ||
1da177e4 LT |
1858 | /* |
1859 | * Major route resolver routine. | |
1860 | */ | |
1861 | ||
89aef892 | 1862 | struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4) |
1da177e4 | 1863 | { |
1da177e4 | 1864 | struct net_device *dev_out = NULL; |
f61759e6 | 1865 | __u8 tos = RT_FL_TOS(fl4); |
813b3b5d DM |
1866 | unsigned int flags = 0; |
1867 | struct fib_result res; | |
5ada5527 | 1868 | struct rtable *rth; |
813b3b5d | 1869 | int orig_oif; |
1da177e4 | 1870 | |
85b91b03 | 1871 | res.tclassid = 0; |
1da177e4 | 1872 | res.fi = NULL; |
8b96d22d | 1873 | res.table = NULL; |
1da177e4 | 1874 | |
813b3b5d DM |
1875 | orig_oif = fl4->flowi4_oif; |
1876 | ||
1fb9489b | 1877 | fl4->flowi4_iif = LOOPBACK_IFINDEX; |
813b3b5d DM |
1878 | fl4->flowi4_tos = tos & IPTOS_RT_MASK; |
1879 | fl4->flowi4_scope = ((tos & RTO_ONLINK) ? | |
1880 | RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); | |
44713b67 | 1881 | |
010c2708 | 1882 | rcu_read_lock(); |
813b3b5d | 1883 | if (fl4->saddr) { |
b23dd4fe | 1884 | rth = ERR_PTR(-EINVAL); |
813b3b5d DM |
1885 | if (ipv4_is_multicast(fl4->saddr) || |
1886 | ipv4_is_lbcast(fl4->saddr) || | |
1887 | ipv4_is_zeronet(fl4->saddr)) | |
1da177e4 LT |
1888 | goto out; |
1889 | ||
1da177e4 LT |
1890 | /* I removed check for oif == dev_out->oif here. |
1891 | It was wrong for two reasons: | |
1ab35276 DL |
1892 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr |
1893 | is assigned to multiple interfaces. | |
1da177e4 LT |
1894 | 2. Moreover, we are allowed to send packets with saddr |
1895 | of another iface. --ANK | |
1896 | */ | |
1897 | ||
813b3b5d DM |
1898 | if (fl4->flowi4_oif == 0 && |
1899 | (ipv4_is_multicast(fl4->daddr) || | |
1900 | ipv4_is_lbcast(fl4->daddr))) { | |
a210d01a | 1901 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 1902 | dev_out = __ip_dev_find(net, fl4->saddr, false); |
a210d01a JA |
1903 | if (dev_out == NULL) |
1904 | goto out; | |
1905 | ||
1da177e4 LT |
1906 | /* Special hack: user can direct multicasts |
1907 | and limited broadcast via necessary interface | |
1908 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
1909 | This hack is not just for fun, it allows | |
1910 | vic,vat and friends to work. | |
1911 | They bind socket to loopback, set ttl to zero | |
1912 | and expect that it will work. | |
1913 | From the viewpoint of routing cache they are broken, | |
1914 | because we are not allowed to build multicast path | |
1915 | with loopback source addr (look, routing cache | |
1916 | cannot know, that ttl is zero, so that packet | |
1917 | will not leave this host and route is valid). | |
1918 | Luckily, this hack is good workaround. | |
1919 | */ | |
1920 | ||
813b3b5d | 1921 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
1922 | goto make_route; |
1923 | } | |
a210d01a | 1924 | |
813b3b5d | 1925 | if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { |
a210d01a | 1926 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 1927 | if (!__ip_dev_find(net, fl4->saddr, false)) |
a210d01a | 1928 | goto out; |
a210d01a | 1929 | } |
1da177e4 LT |
1930 | } |
1931 | ||
1932 | ||
813b3b5d DM |
1933 | if (fl4->flowi4_oif) { |
1934 | dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); | |
b23dd4fe | 1935 | rth = ERR_PTR(-ENODEV); |
1da177e4 LT |
1936 | if (dev_out == NULL) |
1937 | goto out; | |
e5ed6399 HX |
1938 | |
1939 | /* RACE: Check return value of inet_select_addr instead. */ | |
fc75fc83 | 1940 | if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { |
b23dd4fe | 1941 | rth = ERR_PTR(-ENETUNREACH); |
fc75fc83 ED |
1942 | goto out; |
1943 | } | |
813b3b5d DM |
1944 | if (ipv4_is_local_multicast(fl4->daddr) || |
1945 | ipv4_is_lbcast(fl4->daddr)) { | |
1946 | if (!fl4->saddr) | |
1947 | fl4->saddr = inet_select_addr(dev_out, 0, | |
1948 | RT_SCOPE_LINK); | |
1da177e4 LT |
1949 | goto make_route; |
1950 | } | |
813b3b5d DM |
1951 | if (fl4->saddr) { |
1952 | if (ipv4_is_multicast(fl4->daddr)) | |
1953 | fl4->saddr = inet_select_addr(dev_out, 0, | |
1954 | fl4->flowi4_scope); | |
1955 | else if (!fl4->daddr) | |
1956 | fl4->saddr = inet_select_addr(dev_out, 0, | |
1957 | RT_SCOPE_HOST); | |
1da177e4 LT |
1958 | } |
1959 | } | |
1960 | ||
813b3b5d DM |
1961 | if (!fl4->daddr) { |
1962 | fl4->daddr = fl4->saddr; | |
1963 | if (!fl4->daddr) | |
1964 | fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); | |
b40afd0e | 1965 | dev_out = net->loopback_dev; |
1fb9489b | 1966 | fl4->flowi4_oif = LOOPBACK_IFINDEX; |
1da177e4 LT |
1967 | res.type = RTN_LOCAL; |
1968 | flags |= RTCF_LOCAL; | |
1969 | goto make_route; | |
1970 | } | |
1971 | ||
813b3b5d | 1972 | if (fib_lookup(net, fl4, &res)) { |
1da177e4 | 1973 | res.fi = NULL; |
8b96d22d | 1974 | res.table = NULL; |
813b3b5d | 1975 | if (fl4->flowi4_oif) { |
1da177e4 LT |
1976 | /* Apparently, routing tables are wrong. Assume, |
1977 | that the destination is on link. | |
1978 | ||
1979 | WHY? DW. | |
1980 | Because we are allowed to send to iface | |
1981 | even if it has NO routes and NO assigned | |
1982 | addresses. When oif is specified, routing | |
1983 | tables are looked up with only one purpose: | |
1984 | to catch if destination is gatewayed, rather than | |
1985 | direct. Moreover, if MSG_DONTROUTE is set, | |
1986 | we send packet, ignoring both routing tables | |
1987 | and ifaddr state. --ANK | |
1988 | ||
1989 | ||
1990 | We could make it even if oif is unknown, | |
1991 | likely IPv6, but we do not. | |
1992 | */ | |
1993 | ||
813b3b5d DM |
1994 | if (fl4->saddr == 0) |
1995 | fl4->saddr = inet_select_addr(dev_out, 0, | |
1996 | RT_SCOPE_LINK); | |
1da177e4 LT |
1997 | res.type = RTN_UNICAST; |
1998 | goto make_route; | |
1999 | } | |
b23dd4fe | 2000 | rth = ERR_PTR(-ENETUNREACH); |
1da177e4 LT |
2001 | goto out; |
2002 | } | |
1da177e4 LT |
2003 | |
2004 | if (res.type == RTN_LOCAL) { | |
813b3b5d | 2005 | if (!fl4->saddr) { |
9fc3bbb4 | 2006 | if (res.fi->fib_prefsrc) |
813b3b5d | 2007 | fl4->saddr = res.fi->fib_prefsrc; |
9fc3bbb4 | 2008 | else |
813b3b5d | 2009 | fl4->saddr = fl4->daddr; |
9fc3bbb4 | 2010 | } |
b40afd0e | 2011 | dev_out = net->loopback_dev; |
813b3b5d | 2012 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2013 | flags |= RTCF_LOCAL; |
2014 | goto make_route; | |
2015 | } | |
2016 | ||
2017 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
813b3b5d | 2018 | if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0) |
1b7fe593 | 2019 | fib_select_multipath(&res); |
1da177e4 LT |
2020 | else |
2021 | #endif | |
21d8c49e DM |
2022 | if (!res.prefixlen && |
2023 | res.table->tb_num_default > 1 && | |
813b3b5d | 2024 | res.type == RTN_UNICAST && !fl4->flowi4_oif) |
0c838ff1 | 2025 | fib_select_default(&res); |
1da177e4 | 2026 | |
813b3b5d DM |
2027 | if (!fl4->saddr) |
2028 | fl4->saddr = FIB_RES_PREFSRC(net, res); | |
1da177e4 | 2029 | |
1da177e4 | 2030 | dev_out = FIB_RES_DEV(res); |
813b3b5d | 2031 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2032 | |
2033 | ||
2034 | make_route: | |
1a00fee4 | 2035 | rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags); |
1da177e4 | 2036 | |
010c2708 DM |
2037 | out: |
2038 | rcu_read_unlock(); | |
b23dd4fe | 2039 | return rth; |
1da177e4 | 2040 | } |
d8c97a94 ACM |
2041 | EXPORT_SYMBOL_GPL(__ip_route_output_key); |
2042 | ||
ae2688d5 JW |
2043 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) |
2044 | { | |
2045 | return NULL; | |
2046 | } | |
2047 | ||
ebb762f2 | 2048 | static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst) |
ec831ea7 | 2049 | { |
618f9bc7 SK |
2050 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
2051 | ||
2052 | return mtu ? : dst->dev->mtu; | |
ec831ea7 RD |
2053 | } |
2054 | ||
6700c270 DM |
2055 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk, |
2056 | struct sk_buff *skb, u32 mtu) | |
14e50e57 DM |
2057 | { |
2058 | } | |
2059 | ||
6700c270 DM |
2060 | static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk, |
2061 | struct sk_buff *skb) | |
b587ee3b DM |
2062 | { |
2063 | } | |
2064 | ||
0972ddb2 HB |
2065 | static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, |
2066 | unsigned long old) | |
2067 | { | |
2068 | return NULL; | |
2069 | } | |
2070 | ||
14e50e57 DM |
2071 | static struct dst_ops ipv4_dst_blackhole_ops = { |
2072 | .family = AF_INET, | |
09640e63 | 2073 | .protocol = cpu_to_be16(ETH_P_IP), |
ae2688d5 | 2074 | .check = ipv4_blackhole_dst_check, |
ebb762f2 | 2075 | .mtu = ipv4_blackhole_mtu, |
214f45c9 | 2076 | .default_advmss = ipv4_default_advmss, |
14e50e57 | 2077 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, |
b587ee3b | 2078 | .redirect = ipv4_rt_blackhole_redirect, |
0972ddb2 | 2079 | .cow_metrics = ipv4_rt_blackhole_cow_metrics, |
d3aaeb38 | 2080 | .neigh_lookup = ipv4_neigh_lookup, |
14e50e57 DM |
2081 | }; |
2082 | ||
2774c131 | 2083 | struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) |
14e50e57 | 2084 | { |
2774c131 | 2085 | struct rtable *ort = (struct rtable *) dst_orig; |
f5b0a874 | 2086 | struct rtable *rt; |
14e50e57 | 2087 | |
f5b0a874 | 2088 | rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE, 0); |
14e50e57 | 2089 | if (rt) { |
d8d1f30b | 2090 | struct dst_entry *new = &rt->dst; |
14e50e57 | 2091 | |
14e50e57 | 2092 | new->__use = 1; |
352e512c HX |
2093 | new->input = dst_discard; |
2094 | new->output = dst_discard; | |
14e50e57 | 2095 | |
d8d1f30b | 2096 | new->dev = ort->dst.dev; |
14e50e57 DM |
2097 | if (new->dev) |
2098 | dev_hold(new->dev); | |
2099 | ||
9917e1e8 | 2100 | rt->rt_is_input = ort->rt_is_input; |
5e2b61f7 | 2101 | rt->rt_iif = ort->rt_iif; |
5943634f | 2102 | rt->rt_pmtu = ort->rt_pmtu; |
14e50e57 | 2103 | |
e84f84f2 | 2104 | rt->rt_genid = rt_genid(net); |
14e50e57 DM |
2105 | rt->rt_flags = ort->rt_flags; |
2106 | rt->rt_type = ort->rt_type; | |
14e50e57 | 2107 | rt->rt_gateway = ort->rt_gateway; |
14e50e57 | 2108 | |
caacf05e DM |
2109 | INIT_LIST_HEAD(&rt->rt_uncached); |
2110 | ||
14e50e57 DM |
2111 | dst_free(new); |
2112 | } | |
2113 | ||
2774c131 DM |
2114 | dst_release(dst_orig); |
2115 | ||
2116 | return rt ? &rt->dst : ERR_PTR(-ENOMEM); | |
14e50e57 DM |
2117 | } |
2118 | ||
9d6ec938 | 2119 | struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, |
b23dd4fe | 2120 | struct sock *sk) |
1da177e4 | 2121 | { |
9d6ec938 | 2122 | struct rtable *rt = __ip_route_output_key(net, flp4); |
1da177e4 | 2123 | |
b23dd4fe DM |
2124 | if (IS_ERR(rt)) |
2125 | return rt; | |
1da177e4 | 2126 | |
56157872 | 2127 | if (flp4->flowi4_proto) |
9d6ec938 DM |
2128 | rt = (struct rtable *) xfrm_lookup(net, &rt->dst, |
2129 | flowi4_to_flowi(flp4), | |
2130 | sk, 0); | |
1da177e4 | 2131 | |
b23dd4fe | 2132 | return rt; |
1da177e4 | 2133 | } |
d8c97a94 ACM |
2134 | EXPORT_SYMBOL_GPL(ip_route_output_flow); |
2135 | ||
f1ce3062 | 2136 | static int rt_fill_info(struct net *net, __be32 dst, __be32 src, |
15e47304 | 2137 | struct flowi4 *fl4, struct sk_buff *skb, u32 portid, |
f1ce3062 | 2138 | u32 seq, int event, int nowait, unsigned int flags) |
1da177e4 | 2139 | { |
511c3f92 | 2140 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 2141 | struct rtmsg *r; |
be403ea1 | 2142 | struct nlmsghdr *nlh; |
2bc8ca40 | 2143 | unsigned long expires = 0; |
f185071d | 2144 | u32 error; |
521f5490 | 2145 | u32 metrics[RTAX_MAX]; |
be403ea1 | 2146 | |
15e47304 | 2147 | nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags); |
be403ea1 | 2148 | if (nlh == NULL) |
26932566 | 2149 | return -EMSGSIZE; |
be403ea1 TG |
2150 | |
2151 | r = nlmsg_data(nlh); | |
1da177e4 LT |
2152 | r->rtm_family = AF_INET; |
2153 | r->rtm_dst_len = 32; | |
2154 | r->rtm_src_len = 0; | |
d6c0a4f6 | 2155 | r->rtm_tos = fl4->flowi4_tos; |
1da177e4 | 2156 | r->rtm_table = RT_TABLE_MAIN; |
f3756b79 DM |
2157 | if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN)) |
2158 | goto nla_put_failure; | |
1da177e4 LT |
2159 | r->rtm_type = rt->rt_type; |
2160 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2161 | r->rtm_protocol = RTPROT_UNSPEC; | |
2162 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2163 | if (rt->rt_flags & RTCF_NOTIFY) | |
2164 | r->rtm_flags |= RTM_F_NOTIFY; | |
be403ea1 | 2165 | |
f1ce3062 | 2166 | if (nla_put_be32(skb, RTA_DST, dst)) |
f3756b79 | 2167 | goto nla_put_failure; |
1a00fee4 | 2168 | if (src) { |
1da177e4 | 2169 | r->rtm_src_len = 32; |
1a00fee4 | 2170 | if (nla_put_be32(skb, RTA_SRC, src)) |
f3756b79 | 2171 | goto nla_put_failure; |
1da177e4 | 2172 | } |
f3756b79 DM |
2173 | if (rt->dst.dev && |
2174 | nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) | |
2175 | goto nla_put_failure; | |
c7066f70 | 2176 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
2177 | if (rt->dst.tclassid && |
2178 | nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid)) | |
2179 | goto nla_put_failure; | |
1da177e4 | 2180 | #endif |
41347dcd | 2181 | if (!rt_is_input_route(rt) && |
d6c0a4f6 DM |
2182 | fl4->saddr != src) { |
2183 | if (nla_put_be32(skb, RTA_PREFSRC, fl4->saddr)) | |
f3756b79 DM |
2184 | goto nla_put_failure; |
2185 | } | |
f8126f1d | 2186 | if (rt->rt_gateway && |
f3756b79 DM |
2187 | nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway)) |
2188 | goto nla_put_failure; | |
be403ea1 | 2189 | |
521f5490 JA |
2190 | memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics)); |
2191 | if (rt->rt_pmtu) | |
2192 | metrics[RTAX_MTU - 1] = rt->rt_pmtu; | |
2193 | if (rtnetlink_put_metrics(skb, metrics) < 0) | |
be403ea1 TG |
2194 | goto nla_put_failure; |
2195 | ||
b4869889 DM |
2196 | if (fl4->flowi4_mark && |
2197 | nla_put_be32(skb, RTA_MARK, fl4->flowi4_mark)) | |
f3756b79 | 2198 | goto nla_put_failure; |
963bfeee | 2199 | |
d8d1f30b | 2200 | error = rt->dst.error; |
5943634f DM |
2201 | expires = rt->dst.expires; |
2202 | if (expires) { | |
2203 | if (time_before(jiffies, expires)) | |
2204 | expires -= jiffies; | |
2205 | else | |
2206 | expires = 0; | |
1da177e4 | 2207 | } |
be403ea1 | 2208 | |
c7537967 | 2209 | if (rt_is_input_route(rt)) { |
f1ce3062 DM |
2210 | if (nla_put_u32(skb, RTA_IIF, rt->rt_iif)) |
2211 | goto nla_put_failure; | |
1da177e4 LT |
2212 | } |
2213 | ||
f185071d | 2214 | if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0) |
e3703b3d | 2215 | goto nla_put_failure; |
be403ea1 TG |
2216 | |
2217 | return nlmsg_end(skb, nlh); | |
1da177e4 | 2218 | |
be403ea1 | 2219 | nla_put_failure: |
26932566 PM |
2220 | nlmsg_cancel(skb, nlh); |
2221 | return -EMSGSIZE; | |
1da177e4 LT |
2222 | } |
2223 | ||
5e73ea1a | 2224 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg) |
1da177e4 | 2225 | { |
3b1e0a65 | 2226 | struct net *net = sock_net(in_skb->sk); |
d889ce3b TG |
2227 | struct rtmsg *rtm; |
2228 | struct nlattr *tb[RTA_MAX+1]; | |
1da177e4 | 2229 | struct rtable *rt = NULL; |
d6c0a4f6 | 2230 | struct flowi4 fl4; |
9e12bb22 AV |
2231 | __be32 dst = 0; |
2232 | __be32 src = 0; | |
2233 | u32 iif; | |
d889ce3b | 2234 | int err; |
963bfeee | 2235 | int mark; |
1da177e4 LT |
2236 | struct sk_buff *skb; |
2237 | ||
d889ce3b TG |
2238 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); |
2239 | if (err < 0) | |
2240 | goto errout; | |
2241 | ||
2242 | rtm = nlmsg_data(nlh); | |
2243 | ||
1da177e4 | 2244 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
d889ce3b TG |
2245 | if (skb == NULL) { |
2246 | err = -ENOBUFS; | |
2247 | goto errout; | |
2248 | } | |
1da177e4 LT |
2249 | |
2250 | /* Reserve room for dummy headers, this skb can pass | |
2251 | through good chunk of routing engine. | |
2252 | */ | |
459a98ed | 2253 | skb_reset_mac_header(skb); |
c1d2bbe1 | 2254 | skb_reset_network_header(skb); |
d2c962b8 SH |
2255 | |
2256 | /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ | |
eddc9ec5 | 2257 | ip_hdr(skb)->protocol = IPPROTO_ICMP; |
1da177e4 LT |
2258 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); |
2259 | ||
17fb2c64 AV |
2260 | src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0; |
2261 | dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; | |
d889ce3b | 2262 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; |
963bfeee | 2263 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; |
1da177e4 | 2264 | |
d6c0a4f6 DM |
2265 | memset(&fl4, 0, sizeof(fl4)); |
2266 | fl4.daddr = dst; | |
2267 | fl4.saddr = src; | |
2268 | fl4.flowi4_tos = rtm->rtm_tos; | |
2269 | fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0; | |
2270 | fl4.flowi4_mark = mark; | |
2271 | ||
1da177e4 | 2272 | if (iif) { |
d889ce3b TG |
2273 | struct net_device *dev; |
2274 | ||
1937504d | 2275 | dev = __dev_get_by_index(net, iif); |
d889ce3b TG |
2276 | if (dev == NULL) { |
2277 | err = -ENODEV; | |
2278 | goto errout_free; | |
2279 | } | |
2280 | ||
1da177e4 LT |
2281 | skb->protocol = htons(ETH_P_IP); |
2282 | skb->dev = dev; | |
963bfeee | 2283 | skb->mark = mark; |
1da177e4 LT |
2284 | local_bh_disable(); |
2285 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
2286 | local_bh_enable(); | |
d889ce3b | 2287 | |
511c3f92 | 2288 | rt = skb_rtable(skb); |
d8d1f30b CG |
2289 | if (err == 0 && rt->dst.error) |
2290 | err = -rt->dst.error; | |
1da177e4 | 2291 | } else { |
9d6ec938 | 2292 | rt = ip_route_output_key(net, &fl4); |
b23dd4fe DM |
2293 | |
2294 | err = 0; | |
2295 | if (IS_ERR(rt)) | |
2296 | err = PTR_ERR(rt); | |
1da177e4 | 2297 | } |
d889ce3b | 2298 | |
1da177e4 | 2299 | if (err) |
d889ce3b | 2300 | goto errout_free; |
1da177e4 | 2301 | |
d8d1f30b | 2302 | skb_dst_set(skb, &rt->dst); |
1da177e4 LT |
2303 | if (rtm->rtm_flags & RTM_F_NOTIFY) |
2304 | rt->rt_flags |= RTCF_NOTIFY; | |
2305 | ||
f1ce3062 | 2306 | err = rt_fill_info(net, dst, src, &fl4, skb, |
15e47304 | 2307 | NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, |
1937504d | 2308 | RTM_NEWROUTE, 0, 0); |
d889ce3b TG |
2309 | if (err <= 0) |
2310 | goto errout_free; | |
1da177e4 | 2311 | |
15e47304 | 2312 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); |
d889ce3b | 2313 | errout: |
2942e900 | 2314 | return err; |
1da177e4 | 2315 | |
d889ce3b | 2316 | errout_free: |
1da177e4 | 2317 | kfree_skb(skb); |
d889ce3b | 2318 | goto errout; |
1da177e4 LT |
2319 | } |
2320 | ||
2321 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
2322 | { | |
1da177e4 LT |
2323 | return skb->len; |
2324 | } | |
2325 | ||
2326 | void ip_rt_multicast_event(struct in_device *in_dev) | |
2327 | { | |
4ccfe6d4 | 2328 | rt_cache_flush(dev_net(in_dev->dev)); |
1da177e4 LT |
2329 | } |
2330 | ||
2331 | #ifdef CONFIG_SYSCTL | |
81c684d1 | 2332 | static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, |
8d65af78 | 2333 | void __user *buffer, |
1da177e4 LT |
2334 | size_t *lenp, loff_t *ppos) |
2335 | { | |
2336 | if (write) { | |
4ccfe6d4 | 2337 | rt_cache_flush((struct net *)__ctl->extra1); |
1da177e4 | 2338 | return 0; |
e905a9ed | 2339 | } |
1da177e4 LT |
2340 | |
2341 | return -EINVAL; | |
2342 | } | |
2343 | ||
eeb61f71 | 2344 | static ctl_table ipv4_route_table[] = { |
1da177e4 | 2345 | { |
1da177e4 LT |
2346 | .procname = "gc_thresh", |
2347 | .data = &ipv4_dst_ops.gc_thresh, | |
2348 | .maxlen = sizeof(int), | |
2349 | .mode = 0644, | |
6d9f239a | 2350 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2351 | }, |
2352 | { | |
1da177e4 LT |
2353 | .procname = "max_size", |
2354 | .data = &ip_rt_max_size, | |
2355 | .maxlen = sizeof(int), | |
2356 | .mode = 0644, | |
6d9f239a | 2357 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2358 | }, |
2359 | { | |
2360 | /* Deprecated. Use gc_min_interval_ms */ | |
e905a9ed | 2361 | |
1da177e4 LT |
2362 | .procname = "gc_min_interval", |
2363 | .data = &ip_rt_gc_min_interval, | |
2364 | .maxlen = sizeof(int), | |
2365 | .mode = 0644, | |
6d9f239a | 2366 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
2367 | }, |
2368 | { | |
1da177e4 LT |
2369 | .procname = "gc_min_interval_ms", |
2370 | .data = &ip_rt_gc_min_interval, | |
2371 | .maxlen = sizeof(int), | |
2372 | .mode = 0644, | |
6d9f239a | 2373 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 LT |
2374 | }, |
2375 | { | |
1da177e4 LT |
2376 | .procname = "gc_timeout", |
2377 | .data = &ip_rt_gc_timeout, | |
2378 | .maxlen = sizeof(int), | |
2379 | .mode = 0644, | |
6d9f239a | 2380 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 | 2381 | }, |
9f28a2fc ED |
2382 | { |
2383 | .procname = "gc_interval", | |
2384 | .data = &ip_rt_gc_interval, | |
2385 | .maxlen = sizeof(int), | |
2386 | .mode = 0644, | |
2387 | .proc_handler = proc_dointvec_jiffies, | |
2388 | }, | |
1da177e4 | 2389 | { |
1da177e4 LT |
2390 | .procname = "redirect_load", |
2391 | .data = &ip_rt_redirect_load, | |
2392 | .maxlen = sizeof(int), | |
2393 | .mode = 0644, | |
6d9f239a | 2394 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2395 | }, |
2396 | { | |
1da177e4 LT |
2397 | .procname = "redirect_number", |
2398 | .data = &ip_rt_redirect_number, | |
2399 | .maxlen = sizeof(int), | |
2400 | .mode = 0644, | |
6d9f239a | 2401 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2402 | }, |
2403 | { | |
1da177e4 LT |
2404 | .procname = "redirect_silence", |
2405 | .data = &ip_rt_redirect_silence, | |
2406 | .maxlen = sizeof(int), | |
2407 | .mode = 0644, | |
6d9f239a | 2408 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2409 | }, |
2410 | { | |
1da177e4 LT |
2411 | .procname = "error_cost", |
2412 | .data = &ip_rt_error_cost, | |
2413 | .maxlen = sizeof(int), | |
2414 | .mode = 0644, | |
6d9f239a | 2415 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2416 | }, |
2417 | { | |
1da177e4 LT |
2418 | .procname = "error_burst", |
2419 | .data = &ip_rt_error_burst, | |
2420 | .maxlen = sizeof(int), | |
2421 | .mode = 0644, | |
6d9f239a | 2422 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2423 | }, |
2424 | { | |
1da177e4 LT |
2425 | .procname = "gc_elasticity", |
2426 | .data = &ip_rt_gc_elasticity, | |
2427 | .maxlen = sizeof(int), | |
2428 | .mode = 0644, | |
6d9f239a | 2429 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2430 | }, |
2431 | { | |
1da177e4 LT |
2432 | .procname = "mtu_expires", |
2433 | .data = &ip_rt_mtu_expires, | |
2434 | .maxlen = sizeof(int), | |
2435 | .mode = 0644, | |
6d9f239a | 2436 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
2437 | }, |
2438 | { | |
1da177e4 LT |
2439 | .procname = "min_pmtu", |
2440 | .data = &ip_rt_min_pmtu, | |
2441 | .maxlen = sizeof(int), | |
2442 | .mode = 0644, | |
6d9f239a | 2443 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2444 | }, |
2445 | { | |
1da177e4 LT |
2446 | .procname = "min_adv_mss", |
2447 | .data = &ip_rt_min_advmss, | |
2448 | .maxlen = sizeof(int), | |
2449 | .mode = 0644, | |
6d9f239a | 2450 | .proc_handler = proc_dointvec, |
1da177e4 | 2451 | }, |
f8572d8f | 2452 | { } |
1da177e4 | 2453 | }; |
39a23e75 | 2454 | |
39a23e75 DL |
2455 | static struct ctl_table ipv4_route_flush_table[] = { |
2456 | { | |
39a23e75 DL |
2457 | .procname = "flush", |
2458 | .maxlen = sizeof(int), | |
2459 | .mode = 0200, | |
6d9f239a | 2460 | .proc_handler = ipv4_sysctl_rtcache_flush, |
39a23e75 | 2461 | }, |
f8572d8f | 2462 | { }, |
39a23e75 DL |
2463 | }; |
2464 | ||
2465 | static __net_init int sysctl_route_net_init(struct net *net) | |
2466 | { | |
2467 | struct ctl_table *tbl; | |
2468 | ||
2469 | tbl = ipv4_route_flush_table; | |
09ad9bc7 | 2470 | if (!net_eq(net, &init_net)) { |
39a23e75 DL |
2471 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); |
2472 | if (tbl == NULL) | |
2473 | goto err_dup; | |
2474 | } | |
2475 | tbl[0].extra1 = net; | |
2476 | ||
ec8f23ce | 2477 | net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl); |
39a23e75 DL |
2478 | if (net->ipv4.route_hdr == NULL) |
2479 | goto err_reg; | |
2480 | return 0; | |
2481 | ||
2482 | err_reg: | |
2483 | if (tbl != ipv4_route_flush_table) | |
2484 | kfree(tbl); | |
2485 | err_dup: | |
2486 | return -ENOMEM; | |
2487 | } | |
2488 | ||
2489 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
2490 | { | |
2491 | struct ctl_table *tbl; | |
2492 | ||
2493 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
2494 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
2495 | BUG_ON(tbl == ipv4_route_flush_table); | |
2496 | kfree(tbl); | |
2497 | } | |
2498 | ||
2499 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
2500 | .init = sysctl_route_net_init, | |
2501 | .exit = sysctl_route_net_exit, | |
2502 | }; | |
1da177e4 LT |
2503 | #endif |
2504 | ||
3ee94372 | 2505 | static __net_init int rt_genid_init(struct net *net) |
9f5e97e5 | 2506 | { |
b42664f8 | 2507 | atomic_set(&net->rt_genid, 0); |
436c3b66 DM |
2508 | get_random_bytes(&net->ipv4.dev_addr_genid, |
2509 | sizeof(net->ipv4.dev_addr_genid)); | |
9f5e97e5 DL |
2510 | return 0; |
2511 | } | |
2512 | ||
3ee94372 NH |
2513 | static __net_initdata struct pernet_operations rt_genid_ops = { |
2514 | .init = rt_genid_init, | |
9f5e97e5 DL |
2515 | }; |
2516 | ||
c3426b47 DM |
2517 | static int __net_init ipv4_inetpeer_init(struct net *net) |
2518 | { | |
2519 | struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL); | |
2520 | ||
2521 | if (!bp) | |
2522 | return -ENOMEM; | |
2523 | inet_peer_base_init(bp); | |
2524 | net->ipv4.peers = bp; | |
2525 | return 0; | |
2526 | } | |
2527 | ||
2528 | static void __net_exit ipv4_inetpeer_exit(struct net *net) | |
2529 | { | |
2530 | struct inet_peer_base *bp = net->ipv4.peers; | |
2531 | ||
2532 | net->ipv4.peers = NULL; | |
56a6b248 | 2533 | inetpeer_invalidate_tree(bp); |
c3426b47 DM |
2534 | kfree(bp); |
2535 | } | |
2536 | ||
2537 | static __net_initdata struct pernet_operations ipv4_inetpeer_ops = { | |
2538 | .init = ipv4_inetpeer_init, | |
2539 | .exit = ipv4_inetpeer_exit, | |
2540 | }; | |
9f5e97e5 | 2541 | |
c7066f70 | 2542 | #ifdef CONFIG_IP_ROUTE_CLASSID |
7d720c3e | 2543 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; |
c7066f70 | 2544 | #endif /* CONFIG_IP_ROUTE_CLASSID */ |
1da177e4 | 2545 | |
1da177e4 LT |
2546 | int __init ip_rt_init(void) |
2547 | { | |
424c4b70 | 2548 | int rc = 0; |
1da177e4 | 2549 | |
c7066f70 | 2550 | #ifdef CONFIG_IP_ROUTE_CLASSID |
0dcec8c2 | 2551 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); |
1da177e4 LT |
2552 | if (!ip_rt_acct) |
2553 | panic("IP: failed to allocate ip_rt_acct\n"); | |
1da177e4 LT |
2554 | #endif |
2555 | ||
e5d679f3 AD |
2556 | ipv4_dst_ops.kmem_cachep = |
2557 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
20c2df83 | 2558 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 2559 | |
14e50e57 DM |
2560 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; |
2561 | ||
fc66f95c ED |
2562 | if (dst_entries_init(&ipv4_dst_ops) < 0) |
2563 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
2564 | ||
2565 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
2566 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
2567 | ||
89aef892 DM |
2568 | ipv4_dst_ops.gc_thresh = ~0; |
2569 | ip_rt_max_size = INT_MAX; | |
1da177e4 | 2570 | |
1da177e4 LT |
2571 | devinet_init(); |
2572 | ip_fib_init(); | |
2573 | ||
73b38711 | 2574 | if (ip_rt_proc_init()) |
058bd4d2 | 2575 | pr_err("Unable to create route proc files\n"); |
1da177e4 LT |
2576 | #ifdef CONFIG_XFRM |
2577 | xfrm_init(); | |
a33bc5c1 | 2578 | xfrm4_init(ip_rt_max_size); |
1da177e4 | 2579 | #endif |
c7ac8679 | 2580 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL); |
63f3444f | 2581 | |
39a23e75 DL |
2582 | #ifdef CONFIG_SYSCTL |
2583 | register_pernet_subsys(&sysctl_route_ops); | |
2584 | #endif | |
3ee94372 | 2585 | register_pernet_subsys(&rt_genid_ops); |
c3426b47 | 2586 | register_pernet_subsys(&ipv4_inetpeer_ops); |
1da177e4 LT |
2587 | return rc; |
2588 | } | |
2589 | ||
a1bc6eb4 | 2590 | #ifdef CONFIG_SYSCTL |
eeb61f71 AV |
2591 | /* |
2592 | * We really need to sanitize the damn ipv4 init order, then all | |
2593 | * this nonsense will go away. | |
2594 | */ | |
2595 | void __init ip_static_sysctl_init(void) | |
2596 | { | |
4e5ca785 | 2597 | register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table); |
eeb61f71 | 2598 | } |
a1bc6eb4 | 2599 | #endif |