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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * ROUTE - implementation of the IP router. | |
7 | * | |
02c30a84 | 8 | * Authors: Ross Biro |
1da177e4 LT |
9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
10 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
11 | * Linus Torvalds, <Linus.Torvalds@helsinki.fi> | |
12 | * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
13 | * | |
14 | * Fixes: | |
15 | * Alan Cox : Verify area fixes. | |
16 | * Alan Cox : cli() protects routing changes | |
17 | * Rui Oliveira : ICMP routing table updates | |
18 | * (rco@di.uminho.pt) Routing table insertion and update | |
19 | * Linus Torvalds : Rewrote bits to be sensible | |
20 | * Alan Cox : Added BSD route gw semantics | |
e905a9ed | 21 | * Alan Cox : Super /proc >4K |
1da177e4 LT |
22 | * Alan Cox : MTU in route table |
23 | * Alan Cox : MSS actually. Also added the window | |
24 | * clamper. | |
25 | * Sam Lantinga : Fixed route matching in rt_del() | |
26 | * Alan Cox : Routing cache support. | |
27 | * Alan Cox : Removed compatibility cruft. | |
28 | * Alan Cox : RTF_REJECT support. | |
29 | * Alan Cox : TCP irtt support. | |
30 | * Jonathan Naylor : Added Metric support. | |
31 | * Miquel van Smoorenburg : BSD API fixes. | |
32 | * Miquel van Smoorenburg : Metrics. | |
33 | * Alan Cox : Use __u32 properly | |
34 | * Alan Cox : Aligned routing errors more closely with BSD | |
35 | * our system is still very different. | |
36 | * Alan Cox : Faster /proc handling | |
37 | * Alexey Kuznetsov : Massive rework to support tree based routing, | |
38 | * routing caches and better behaviour. | |
e905a9ed | 39 | * |
1da177e4 LT |
40 | * Olaf Erb : irtt wasn't being copied right. |
41 | * Bjorn Ekwall : Kerneld route support. | |
42 | * Alan Cox : Multicast fixed (I hope) | |
43 | * Pavel Krauz : Limited broadcast fixed | |
44 | * Mike McLagan : Routing by source | |
45 | * Alexey Kuznetsov : End of old history. Split to fib.c and | |
46 | * route.c and rewritten from scratch. | |
47 | * Andi Kleen : Load-limit warning messages. | |
48 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. | |
49 | * Vitaly E. Lavrov : Race condition in ip_route_input_slow. | |
50 | * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow. | |
51 | * Vladimir V. Ivanov : IP rule info (flowid) is really useful. | |
52 | * Marc Boucher : routing by fwmark | |
53 | * Robert Olsson : Added rt_cache statistics | |
54 | * Arnaldo C. Melo : Convert proc stuff to seq_file | |
bb1d23b0 | 55 | * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes. |
cef2685e IS |
56 | * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect |
57 | * Ilia Sotnikov : Removed TOS from hash calculations | |
1da177e4 LT |
58 | * |
59 | * This program is free software; you can redistribute it and/or | |
60 | * modify it under the terms of the GNU General Public License | |
61 | * as published by the Free Software Foundation; either version | |
62 | * 2 of the License, or (at your option) any later version. | |
63 | */ | |
64 | ||
afd46503 JP |
65 | #define pr_fmt(fmt) "IPv4: " fmt |
66 | ||
1da177e4 | 67 | #include <linux/module.h> |
7c0f6ba6 | 68 | #include <linux/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> |
73f156a6 | 92 | #include <linux/jhash.h> |
352e512c | 93 | #include <net/dst.h> |
1b7179d3 | 94 | #include <net/dst_metadata.h> |
457c4cbc | 95 | #include <net/net_namespace.h> |
1da177e4 LT |
96 | #include <net/protocol.h> |
97 | #include <net/ip.h> | |
98 | #include <net/route.h> | |
99 | #include <net/inetpeer.h> | |
100 | #include <net/sock.h> | |
101 | #include <net/ip_fib.h> | |
102 | #include <net/arp.h> | |
103 | #include <net/tcp.h> | |
104 | #include <net/icmp.h> | |
105 | #include <net/xfrm.h> | |
571e7226 | 106 | #include <net/lwtunnel.h> |
8d71740c | 107 | #include <net/netevent.h> |
63f3444f | 108 | #include <net/rtnetlink.h> |
1da177e4 LT |
109 | #ifdef CONFIG_SYSCTL |
110 | #include <linux/sysctl.h> | |
7426a564 | 111 | #include <linux/kmemleak.h> |
1da177e4 | 112 | #endif |
6e5714ea | 113 | #include <net/secure_seq.h> |
1b7179d3 | 114 | #include <net/ip_tunnels.h> |
385add90 | 115 | #include <net/l3mdev.h> |
1da177e4 | 116 | |
b6179813 RP |
117 | #include "fib_lookup.h" |
118 | ||
68a5e3dd | 119 | #define RT_FL_TOS(oldflp4) \ |
f61759e6 | 120 | ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK)) |
1da177e4 | 121 | |
1da177e4 LT |
122 | #define RT_GC_TIMEOUT (300*HZ) |
123 | ||
1da177e4 | 124 | static int ip_rt_max_size; |
817bc4db SH |
125 | static int ip_rt_redirect_number __read_mostly = 9; |
126 | static int ip_rt_redirect_load __read_mostly = HZ / 50; | |
127 | static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); | |
128 | static int ip_rt_error_cost __read_mostly = HZ; | |
129 | static int ip_rt_error_burst __read_mostly = 5 * HZ; | |
817bc4db SH |
130 | static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; |
131 | static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; | |
132 | static int ip_rt_min_advmss __read_mostly = 256; | |
9f28a2fc | 133 | |
deed49df | 134 | static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; |
1da177e4 LT |
135 | /* |
136 | * Interface to generic destination cache. | |
137 | */ | |
138 | ||
139 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
0dbaee3b | 140 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst); |
ebb762f2 | 141 | static unsigned int ipv4_mtu(const struct dst_entry *dst); |
1da177e4 LT |
142 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); |
143 | static void ipv4_link_failure(struct sk_buff *skb); | |
6700c270 DM |
144 | static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, |
145 | struct sk_buff *skb, u32 mtu); | |
146 | static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, | |
147 | struct sk_buff *skb); | |
caacf05e | 148 | static void ipv4_dst_destroy(struct dst_entry *dst); |
1da177e4 | 149 | |
62fa8a84 DM |
150 | static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old) |
151 | { | |
31248731 DM |
152 | WARN_ON(1); |
153 | return NULL; | |
62fa8a84 DM |
154 | } |
155 | ||
f894cbf8 DM |
156 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, |
157 | struct sk_buff *skb, | |
158 | const void *daddr); | |
63fca65d | 159 | static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr); |
d3aaeb38 | 160 | |
1da177e4 LT |
161 | static struct dst_ops ipv4_dst_ops = { |
162 | .family = AF_INET, | |
1da177e4 | 163 | .check = ipv4_dst_check, |
0dbaee3b | 164 | .default_advmss = ipv4_default_advmss, |
ebb762f2 | 165 | .mtu = ipv4_mtu, |
62fa8a84 | 166 | .cow_metrics = ipv4_cow_metrics, |
caacf05e | 167 | .destroy = ipv4_dst_destroy, |
1da177e4 LT |
168 | .negative_advice = ipv4_negative_advice, |
169 | .link_failure = ipv4_link_failure, | |
170 | .update_pmtu = ip_rt_update_pmtu, | |
e47a185b | 171 | .redirect = ip_do_redirect, |
b92dacd4 | 172 | .local_out = __ip_local_out, |
d3aaeb38 | 173 | .neigh_lookup = ipv4_neigh_lookup, |
63fca65d | 174 | .confirm_neigh = ipv4_confirm_neigh, |
1da177e4 LT |
175 | }; |
176 | ||
177 | #define ECN_OR_COST(class) TC_PRIO_##class | |
178 | ||
4839c52b | 179 | const __u8 ip_tos2prio[16] = { |
1da177e4 | 180 | TC_PRIO_BESTEFFORT, |
4a2b9c37 | 181 | ECN_OR_COST(BESTEFFORT), |
1da177e4 LT |
182 | TC_PRIO_BESTEFFORT, |
183 | ECN_OR_COST(BESTEFFORT), | |
184 | TC_PRIO_BULK, | |
185 | ECN_OR_COST(BULK), | |
186 | TC_PRIO_BULK, | |
187 | ECN_OR_COST(BULK), | |
188 | TC_PRIO_INTERACTIVE, | |
189 | ECN_OR_COST(INTERACTIVE), | |
190 | TC_PRIO_INTERACTIVE, | |
191 | ECN_OR_COST(INTERACTIVE), | |
192 | TC_PRIO_INTERACTIVE_BULK, | |
193 | ECN_OR_COST(INTERACTIVE_BULK), | |
194 | TC_PRIO_INTERACTIVE_BULK, | |
195 | ECN_OR_COST(INTERACTIVE_BULK) | |
196 | }; | |
d4a96865 | 197 | EXPORT_SYMBOL(ip_tos2prio); |
1da177e4 | 198 | |
2f970d83 | 199 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); |
3ed66e91 | 200 | #define RT_CACHE_STAT_INC(field) raw_cpu_inc(rt_cache_stat.field) |
1da177e4 | 201 | |
1da177e4 | 202 | #ifdef CONFIG_PROC_FS |
1da177e4 LT |
203 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) |
204 | { | |
29e75252 | 205 | if (*pos) |
89aef892 | 206 | return NULL; |
29e75252 | 207 | return SEQ_START_TOKEN; |
1da177e4 LT |
208 | } |
209 | ||
210 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
211 | { | |
1da177e4 | 212 | ++*pos; |
89aef892 | 213 | return NULL; |
1da177e4 LT |
214 | } |
215 | ||
216 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
217 | { | |
1da177e4 LT |
218 | } |
219 | ||
220 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
221 | { | |
222 | if (v == SEQ_START_TOKEN) | |
223 | seq_printf(seq, "%-127s\n", | |
224 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
225 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
226 | "HHUptod\tSpecDst"); | |
e905a9ed | 227 | return 0; |
1da177e4 LT |
228 | } |
229 | ||
f690808e | 230 | static const struct seq_operations rt_cache_seq_ops = { |
1da177e4 LT |
231 | .start = rt_cache_seq_start, |
232 | .next = rt_cache_seq_next, | |
233 | .stop = rt_cache_seq_stop, | |
234 | .show = rt_cache_seq_show, | |
235 | }; | |
236 | ||
237 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
238 | { | |
89aef892 | 239 | return seq_open(file, &rt_cache_seq_ops); |
1da177e4 LT |
240 | } |
241 | ||
9a32144e | 242 | static const struct file_operations rt_cache_seq_fops = { |
1da177e4 LT |
243 | .owner = THIS_MODULE, |
244 | .open = rt_cache_seq_open, | |
245 | .read = seq_read, | |
246 | .llseek = seq_lseek, | |
89aef892 | 247 | .release = seq_release, |
1da177e4 LT |
248 | }; |
249 | ||
250 | ||
251 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
252 | { | |
253 | int cpu; | |
254 | ||
255 | if (*pos == 0) | |
256 | return SEQ_START_TOKEN; | |
257 | ||
0f23174a | 258 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
259 | if (!cpu_possible(cpu)) |
260 | continue; | |
261 | *pos = cpu+1; | |
2f970d83 | 262 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
263 | } |
264 | return NULL; | |
265 | } | |
266 | ||
267 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
268 | { | |
269 | int cpu; | |
270 | ||
0f23174a | 271 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { |
1da177e4 LT |
272 | if (!cpu_possible(cpu)) |
273 | continue; | |
274 | *pos = cpu+1; | |
2f970d83 | 275 | return &per_cpu(rt_cache_stat, cpu); |
1da177e4 LT |
276 | } |
277 | return NULL; | |
e905a9ed | 278 | |
1da177e4 LT |
279 | } |
280 | ||
281 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
282 | { | |
283 | ||
284 | } | |
285 | ||
286 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
287 | { | |
288 | struct rt_cache_stat *st = v; | |
289 | ||
290 | if (v == SEQ_START_TOKEN) { | |
5bec0039 | 291 | 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 |
292 | return 0; |
293 | } | |
e905a9ed | 294 | |
1da177e4 LT |
295 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " |
296 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
fc66f95c | 297 | dst_entries_get_slow(&ipv4_dst_ops), |
0baf2b35 | 298 | 0, /* st->in_hit */ |
1da177e4 LT |
299 | st->in_slow_tot, |
300 | st->in_slow_mc, | |
301 | st->in_no_route, | |
302 | st->in_brd, | |
303 | st->in_martian_dst, | |
304 | st->in_martian_src, | |
305 | ||
0baf2b35 | 306 | 0, /* st->out_hit */ |
1da177e4 | 307 | st->out_slow_tot, |
e905a9ed | 308 | st->out_slow_mc, |
1da177e4 | 309 | |
0baf2b35 ED |
310 | 0, /* st->gc_total */ |
311 | 0, /* st->gc_ignored */ | |
312 | 0, /* st->gc_goal_miss */ | |
313 | 0, /* st->gc_dst_overflow */ | |
314 | 0, /* st->in_hlist_search */ | |
315 | 0 /* st->out_hlist_search */ | |
1da177e4 LT |
316 | ); |
317 | return 0; | |
318 | } | |
319 | ||
f690808e | 320 | static const struct seq_operations rt_cpu_seq_ops = { |
1da177e4 LT |
321 | .start = rt_cpu_seq_start, |
322 | .next = rt_cpu_seq_next, | |
323 | .stop = rt_cpu_seq_stop, | |
324 | .show = rt_cpu_seq_show, | |
325 | }; | |
326 | ||
327 | ||
328 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
329 | { | |
330 | return seq_open(file, &rt_cpu_seq_ops); | |
331 | } | |
332 | ||
9a32144e | 333 | static const struct file_operations rt_cpu_seq_fops = { |
1da177e4 LT |
334 | .owner = THIS_MODULE, |
335 | .open = rt_cpu_seq_open, | |
336 | .read = seq_read, | |
337 | .llseek = seq_lseek, | |
338 | .release = seq_release, | |
339 | }; | |
340 | ||
c7066f70 | 341 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 342 | static int rt_acct_proc_show(struct seq_file *m, void *v) |
78c686e9 | 343 | { |
a661c419 AD |
344 | struct ip_rt_acct *dst, *src; |
345 | unsigned int i, j; | |
346 | ||
347 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
348 | if (!dst) | |
349 | return -ENOMEM; | |
350 | ||
351 | for_each_possible_cpu(i) { | |
352 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
353 | for (j = 0; j < 256; j++) { | |
354 | dst[j].o_bytes += src[j].o_bytes; | |
355 | dst[j].o_packets += src[j].o_packets; | |
356 | dst[j].i_bytes += src[j].i_bytes; | |
357 | dst[j].i_packets += src[j].i_packets; | |
358 | } | |
78c686e9 PE |
359 | } |
360 | ||
a661c419 AD |
361 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); |
362 | kfree(dst); | |
363 | return 0; | |
364 | } | |
78c686e9 | 365 | |
a661c419 AD |
366 | static int rt_acct_proc_open(struct inode *inode, struct file *file) |
367 | { | |
368 | return single_open(file, rt_acct_proc_show, NULL); | |
78c686e9 | 369 | } |
a661c419 AD |
370 | |
371 | static const struct file_operations rt_acct_proc_fops = { | |
372 | .owner = THIS_MODULE, | |
373 | .open = rt_acct_proc_open, | |
374 | .read = seq_read, | |
375 | .llseek = seq_lseek, | |
376 | .release = single_release, | |
377 | }; | |
78c686e9 | 378 | #endif |
107f1634 | 379 | |
73b38711 | 380 | static int __net_init ip_rt_do_proc_init(struct net *net) |
107f1634 PE |
381 | { |
382 | struct proc_dir_entry *pde; | |
383 | ||
d4beaa66 G |
384 | pde = proc_create("rt_cache", S_IRUGO, net->proc_net, |
385 | &rt_cache_seq_fops); | |
107f1634 PE |
386 | if (!pde) |
387 | goto err1; | |
388 | ||
77020720 WC |
389 | pde = proc_create("rt_cache", S_IRUGO, |
390 | net->proc_net_stat, &rt_cpu_seq_fops); | |
107f1634 PE |
391 | if (!pde) |
392 | goto err2; | |
393 | ||
c7066f70 | 394 | #ifdef CONFIG_IP_ROUTE_CLASSID |
a661c419 | 395 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); |
107f1634 PE |
396 | if (!pde) |
397 | goto err3; | |
398 | #endif | |
399 | return 0; | |
400 | ||
c7066f70 | 401 | #ifdef CONFIG_IP_ROUTE_CLASSID |
107f1634 PE |
402 | err3: |
403 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
404 | #endif | |
405 | err2: | |
406 | remove_proc_entry("rt_cache", net->proc_net); | |
407 | err1: | |
408 | return -ENOMEM; | |
409 | } | |
73b38711 DL |
410 | |
411 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
412 | { | |
413 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
414 | remove_proc_entry("rt_cache", net->proc_net); | |
c7066f70 | 415 | #ifdef CONFIG_IP_ROUTE_CLASSID |
73b38711 | 416 | remove_proc_entry("rt_acct", net->proc_net); |
0a931acf | 417 | #endif |
73b38711 DL |
418 | } |
419 | ||
420 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
421 | .init = ip_rt_do_proc_init, | |
422 | .exit = ip_rt_do_proc_exit, | |
423 | }; | |
424 | ||
425 | static int __init ip_rt_proc_init(void) | |
426 | { | |
427 | return register_pernet_subsys(&ip_rt_proc_ops); | |
428 | } | |
429 | ||
107f1634 | 430 | #else |
73b38711 | 431 | static inline int ip_rt_proc_init(void) |
107f1634 PE |
432 | { |
433 | return 0; | |
434 | } | |
1da177e4 | 435 | #endif /* CONFIG_PROC_FS */ |
e905a9ed | 436 | |
4331debc | 437 | static inline bool rt_is_expired(const struct rtable *rth) |
e84f84f2 | 438 | { |
ca4c3fc2 | 439 | return rth->rt_genid != rt_genid_ipv4(dev_net(rth->dst.dev)); |
e84f84f2 DL |
440 | } |
441 | ||
4ccfe6d4 | 442 | void rt_cache_flush(struct net *net) |
1da177e4 | 443 | { |
ca4c3fc2 | 444 | rt_genid_bump_ipv4(net); |
98376387 ED |
445 | } |
446 | ||
f894cbf8 DM |
447 | static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, |
448 | struct sk_buff *skb, | |
449 | const void *daddr) | |
3769cffb | 450 | { |
d3aaeb38 DM |
451 | struct net_device *dev = dst->dev; |
452 | const __be32 *pkey = daddr; | |
39232973 | 453 | const struct rtable *rt; |
3769cffb DM |
454 | struct neighbour *n; |
455 | ||
39232973 | 456 | rt = (const struct rtable *) dst; |
a263b309 | 457 | if (rt->rt_gateway) |
39232973 | 458 | pkey = (const __be32 *) &rt->rt_gateway; |
f894cbf8 DM |
459 | else if (skb) |
460 | pkey = &ip_hdr(skb)->daddr; | |
d3aaeb38 | 461 | |
80703d26 | 462 | n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey); |
d3aaeb38 DM |
463 | if (n) |
464 | return n; | |
32092ecf | 465 | return neigh_create(&arp_tbl, pkey, dev); |
d3aaeb38 DM |
466 | } |
467 | ||
63fca65d JA |
468 | static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr) |
469 | { | |
470 | struct net_device *dev = dst->dev; | |
471 | const __be32 *pkey = daddr; | |
472 | const struct rtable *rt; | |
473 | ||
474 | rt = (const struct rtable *)dst; | |
475 | if (rt->rt_gateway) | |
476 | pkey = (const __be32 *)&rt->rt_gateway; | |
477 | else if (!daddr || | |
478 | (rt->rt_flags & | |
479 | (RTCF_MULTICAST | RTCF_BROADCAST | RTCF_LOCAL))) | |
480 | return; | |
481 | ||
482 | __ipv4_confirm_neigh(dev, *(__force u32 *)pkey); | |
483 | } | |
484 | ||
04ca6973 | 485 | #define IP_IDENTS_SZ 2048u |
04ca6973 | 486 | |
355b590c ED |
487 | static atomic_t *ip_idents __read_mostly; |
488 | static u32 *ip_tstamps __read_mostly; | |
04ca6973 ED |
489 | |
490 | /* In order to protect privacy, we add a perturbation to identifiers | |
491 | * if one generator is seldom used. This makes hard for an attacker | |
492 | * to infer how many packets were sent between two points in time. | |
493 | */ | |
494 | u32 ip_idents_reserve(u32 hash, int segs) | |
495 | { | |
355b590c ED |
496 | u32 *p_tstamp = ip_tstamps + hash % IP_IDENTS_SZ; |
497 | atomic_t *p_id = ip_idents + hash % IP_IDENTS_SZ; | |
6aa7de05 | 498 | u32 old = READ_ONCE(*p_tstamp); |
04ca6973 | 499 | u32 now = (u32)jiffies; |
adb03115 | 500 | u32 new, delta = 0; |
04ca6973 | 501 | |
355b590c | 502 | if (old != now && cmpxchg(p_tstamp, old, now) == old) |
04ca6973 ED |
503 | delta = prandom_u32_max(now - old); |
504 | ||
adb03115 ED |
505 | /* Do not use atomic_add_return() as it makes UBSAN unhappy */ |
506 | do { | |
507 | old = (u32)atomic_read(p_id); | |
508 | new = old + delta + segs; | |
509 | } while (atomic_cmpxchg(p_id, old, new) != old); | |
510 | ||
511 | return new - segs; | |
04ca6973 ED |
512 | } |
513 | EXPORT_SYMBOL(ip_idents_reserve); | |
1da177e4 | 514 | |
b6a7719a | 515 | void __ip_select_ident(struct net *net, struct iphdr *iph, int segs) |
1da177e4 | 516 | { |
73f156a6 ED |
517 | static u32 ip_idents_hashrnd __read_mostly; |
518 | u32 hash, id; | |
1da177e4 | 519 | |
73f156a6 | 520 | net_get_random_once(&ip_idents_hashrnd, sizeof(ip_idents_hashrnd)); |
1da177e4 | 521 | |
04ca6973 ED |
522 | hash = jhash_3words((__force u32)iph->daddr, |
523 | (__force u32)iph->saddr, | |
b6a7719a | 524 | iph->protocol ^ net_hash_mix(net), |
04ca6973 | 525 | ip_idents_hashrnd); |
73f156a6 ED |
526 | id = ip_idents_reserve(hash, segs); |
527 | iph->id = htons(id); | |
1da177e4 | 528 | } |
4bc2f18b | 529 | EXPORT_SYMBOL(__ip_select_ident); |
1da177e4 | 530 | |
e2d118a1 LC |
531 | static void __build_flow_key(const struct net *net, struct flowi4 *fl4, |
532 | const struct sock *sk, | |
4895c771 DM |
533 | const struct iphdr *iph, |
534 | int oif, u8 tos, | |
535 | u8 prot, u32 mark, int flow_flags) | |
536 | { | |
537 | if (sk) { | |
538 | const struct inet_sock *inet = inet_sk(sk); | |
539 | ||
540 | oif = sk->sk_bound_dev_if; | |
541 | mark = sk->sk_mark; | |
542 | tos = RT_CONN_FLAGS(sk); | |
543 | prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol; | |
544 | } | |
545 | flowi4_init_output(fl4, oif, mark, tos, | |
546 | RT_SCOPE_UNIVERSE, prot, | |
547 | flow_flags, | |
e2d118a1 LC |
548 | iph->daddr, iph->saddr, 0, 0, |
549 | sock_net_uid(net, sk)); | |
4895c771 DM |
550 | } |
551 | ||
5abf7f7e ED |
552 | static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb, |
553 | const struct sock *sk) | |
4895c771 | 554 | { |
d109e61b | 555 | const struct net *net = dev_net(skb->dev); |
4895c771 DM |
556 | const struct iphdr *iph = ip_hdr(skb); |
557 | int oif = skb->dev->ifindex; | |
558 | u8 tos = RT_TOS(iph->tos); | |
559 | u8 prot = iph->protocol; | |
560 | u32 mark = skb->mark; | |
561 | ||
d109e61b | 562 | __build_flow_key(net, fl4, sk, iph, oif, tos, prot, mark, 0); |
4895c771 DM |
563 | } |
564 | ||
5abf7f7e | 565 | static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk) |
4895c771 DM |
566 | { |
567 | const struct inet_sock *inet = inet_sk(sk); | |
5abf7f7e | 568 | const struct ip_options_rcu *inet_opt; |
4895c771 DM |
569 | __be32 daddr = inet->inet_daddr; |
570 | ||
571 | rcu_read_lock(); | |
572 | inet_opt = rcu_dereference(inet->inet_opt); | |
573 | if (inet_opt && inet_opt->opt.srr) | |
574 | daddr = inet_opt->opt.faddr; | |
575 | flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark, | |
576 | RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, | |
577 | inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, | |
578 | inet_sk_flowi_flags(sk), | |
e2d118a1 | 579 | daddr, inet->inet_saddr, 0, 0, sk->sk_uid); |
4895c771 DM |
580 | rcu_read_unlock(); |
581 | } | |
582 | ||
5abf7f7e ED |
583 | static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk, |
584 | const struct sk_buff *skb) | |
4895c771 DM |
585 | { |
586 | if (skb) | |
587 | build_skb_flow_key(fl4, skb, sk); | |
588 | else | |
589 | build_sk_flow_key(fl4, sk); | |
590 | } | |
591 | ||
c5038a83 | 592 | static DEFINE_SPINLOCK(fnhe_lock); |
4895c771 | 593 | |
2ffae99d TT |
594 | static void fnhe_flush_routes(struct fib_nh_exception *fnhe) |
595 | { | |
596 | struct rtable *rt; | |
597 | ||
598 | rt = rcu_dereference(fnhe->fnhe_rth_input); | |
599 | if (rt) { | |
600 | RCU_INIT_POINTER(fnhe->fnhe_rth_input, NULL); | |
95c47f9c | 601 | dst_dev_put(&rt->dst); |
0830106c | 602 | dst_release(&rt->dst); |
2ffae99d TT |
603 | } |
604 | rt = rcu_dereference(fnhe->fnhe_rth_output); | |
605 | if (rt) { | |
606 | RCU_INIT_POINTER(fnhe->fnhe_rth_output, NULL); | |
95c47f9c | 607 | dst_dev_put(&rt->dst); |
0830106c | 608 | dst_release(&rt->dst); |
2ffae99d TT |
609 | } |
610 | } | |
611 | ||
aee06da6 | 612 | static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash) |
4895c771 DM |
613 | { |
614 | struct fib_nh_exception *fnhe, *oldest; | |
615 | ||
616 | oldest = rcu_dereference(hash->chain); | |
617 | for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe; | |
618 | fnhe = rcu_dereference(fnhe->fnhe_next)) { | |
619 | if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp)) | |
620 | oldest = fnhe; | |
621 | } | |
2ffae99d | 622 | fnhe_flush_routes(oldest); |
4895c771 DM |
623 | return oldest; |
624 | } | |
625 | ||
d3a25c98 DM |
626 | static inline u32 fnhe_hashfun(__be32 daddr) |
627 | { | |
d546c621 | 628 | static u32 fnhe_hashrnd __read_mostly; |
d3a25c98 DM |
629 | u32 hval; |
630 | ||
d546c621 ED |
631 | net_get_random_once(&fnhe_hashrnd, sizeof(fnhe_hashrnd)); |
632 | hval = jhash_1word((__force u32) daddr, fnhe_hashrnd); | |
633 | return hash_32(hval, FNHE_HASH_SHIFT); | |
d3a25c98 DM |
634 | } |
635 | ||
387aa65a TT |
636 | static void fill_route_from_fnhe(struct rtable *rt, struct fib_nh_exception *fnhe) |
637 | { | |
638 | rt->rt_pmtu = fnhe->fnhe_pmtu; | |
639 | rt->dst.expires = fnhe->fnhe_expires; | |
640 | ||
641 | if (fnhe->fnhe_gw) { | |
642 | rt->rt_flags |= RTCF_REDIRECTED; | |
643 | rt->rt_gateway = fnhe->fnhe_gw; | |
644 | rt->rt_uses_gateway = 1; | |
645 | } | |
646 | } | |
647 | ||
aee06da6 JA |
648 | static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw, |
649 | u32 pmtu, unsigned long expires) | |
4895c771 | 650 | { |
aee06da6 | 651 | struct fnhe_hash_bucket *hash; |
4895c771 | 652 | struct fib_nh_exception *fnhe; |
387aa65a | 653 | struct rtable *rt; |
cebe84c6 | 654 | u32 genid, hval; |
387aa65a | 655 | unsigned int i; |
4895c771 | 656 | int depth; |
cebe84c6 XL |
657 | |
658 | genid = fnhe_genid(dev_net(nh->nh_dev)); | |
659 | hval = fnhe_hashfun(daddr); | |
aee06da6 | 660 | |
c5038a83 | 661 | spin_lock_bh(&fnhe_lock); |
4895c771 | 662 | |
caa41527 | 663 | hash = rcu_dereference(nh->nh_exceptions); |
4895c771 | 664 | if (!hash) { |
aee06da6 | 665 | hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC); |
4895c771 | 666 | if (!hash) |
aee06da6 | 667 | goto out_unlock; |
caa41527 | 668 | rcu_assign_pointer(nh->nh_exceptions, hash); |
4895c771 DM |
669 | } |
670 | ||
4895c771 DM |
671 | hash += hval; |
672 | ||
673 | depth = 0; | |
674 | for (fnhe = rcu_dereference(hash->chain); fnhe; | |
675 | fnhe = rcu_dereference(fnhe->fnhe_next)) { | |
676 | if (fnhe->fnhe_daddr == daddr) | |
aee06da6 | 677 | break; |
4895c771 DM |
678 | depth++; |
679 | } | |
680 | ||
aee06da6 | 681 | if (fnhe) { |
cebe84c6 XL |
682 | if (fnhe->fnhe_genid != genid) |
683 | fnhe->fnhe_genid = genid; | |
aee06da6 JA |
684 | if (gw) |
685 | fnhe->fnhe_gw = gw; | |
e39d5246 | 686 | if (pmtu) |
aee06da6 | 687 | fnhe->fnhe_pmtu = pmtu; |
e39d5246 | 688 | fnhe->fnhe_expires = max(1UL, expires); |
387aa65a | 689 | /* Update all cached dsts too */ |
2ffae99d TT |
690 | rt = rcu_dereference(fnhe->fnhe_rth_input); |
691 | if (rt) | |
692 | fill_route_from_fnhe(rt, fnhe); | |
693 | rt = rcu_dereference(fnhe->fnhe_rth_output); | |
387aa65a TT |
694 | if (rt) |
695 | fill_route_from_fnhe(rt, fnhe); | |
aee06da6 JA |
696 | } else { |
697 | if (depth > FNHE_RECLAIM_DEPTH) | |
698 | fnhe = fnhe_oldest(hash); | |
699 | else { | |
700 | fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC); | |
701 | if (!fnhe) | |
702 | goto out_unlock; | |
703 | ||
704 | fnhe->fnhe_next = hash->chain; | |
705 | rcu_assign_pointer(hash->chain, fnhe); | |
706 | } | |
cebe84c6 | 707 | fnhe->fnhe_genid = genid; |
aee06da6 JA |
708 | fnhe->fnhe_daddr = daddr; |
709 | fnhe->fnhe_gw = gw; | |
710 | fnhe->fnhe_pmtu = pmtu; | |
711 | fnhe->fnhe_expires = expires; | |
387aa65a TT |
712 | |
713 | /* Exception created; mark the cached routes for the nexthop | |
714 | * stale, so anyone caching it rechecks if this exception | |
715 | * applies to them. | |
716 | */ | |
2ffae99d TT |
717 | rt = rcu_dereference(nh->nh_rth_input); |
718 | if (rt) | |
719 | rt->dst.obsolete = DST_OBSOLETE_KILL; | |
720 | ||
387aa65a TT |
721 | for_each_possible_cpu(i) { |
722 | struct rtable __rcu **prt; | |
723 | prt = per_cpu_ptr(nh->nh_pcpu_rth_output, i); | |
724 | rt = rcu_dereference(*prt); | |
725 | if (rt) | |
726 | rt->dst.obsolete = DST_OBSOLETE_KILL; | |
727 | } | |
4895c771 | 728 | } |
4895c771 | 729 | |
4895c771 | 730 | fnhe->fnhe_stamp = jiffies; |
aee06da6 JA |
731 | |
732 | out_unlock: | |
c5038a83 | 733 | spin_unlock_bh(&fnhe_lock); |
4895c771 DM |
734 | } |
735 | ||
ceb33206 DM |
736 | static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4, |
737 | bool kill_route) | |
1da177e4 | 738 | { |
e47a185b | 739 | __be32 new_gw = icmp_hdr(skb)->un.gateway; |
94206125 | 740 | __be32 old_gw = ip_hdr(skb)->saddr; |
e47a185b | 741 | struct net_device *dev = skb->dev; |
e47a185b | 742 | struct in_device *in_dev; |
4895c771 | 743 | struct fib_result res; |
e47a185b | 744 | struct neighbour *n; |
317805b8 | 745 | struct net *net; |
1da177e4 | 746 | |
94206125 DM |
747 | switch (icmp_hdr(skb)->code & 7) { |
748 | case ICMP_REDIR_NET: | |
749 | case ICMP_REDIR_NETTOS: | |
750 | case ICMP_REDIR_HOST: | |
751 | case ICMP_REDIR_HOSTTOS: | |
752 | break; | |
753 | ||
754 | default: | |
755 | return; | |
756 | } | |
757 | ||
e47a185b DM |
758 | if (rt->rt_gateway != old_gw) |
759 | return; | |
760 | ||
761 | in_dev = __in_dev_get_rcu(dev); | |
762 | if (!in_dev) | |
763 | return; | |
764 | ||
c346dca1 | 765 | net = dev_net(dev); |
9d4fb27d JP |
766 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || |
767 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
768 | ipv4_is_zeronet(new_gw)) | |
1da177e4 LT |
769 | goto reject_redirect; |
770 | ||
771 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
772 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
773 | goto reject_redirect; | |
774 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
775 | goto reject_redirect; | |
776 | } else { | |
317805b8 | 777 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) |
1da177e4 LT |
778 | goto reject_redirect; |
779 | } | |
780 | ||
969447f2 SSL |
781 | n = __ipv4_neigh_lookup(rt->dst.dev, new_gw); |
782 | if (!n) | |
783 | n = neigh_create(&arp_tbl, &new_gw, rt->dst.dev); | |
2c1a4311 | 784 | if (!IS_ERR(n)) { |
e47a185b DM |
785 | if (!(n->nud_state & NUD_VALID)) { |
786 | neigh_event_send(n, NULL); | |
787 | } else { | |
0eeb075f | 788 | if (fib_lookup(net, fl4, &res, 0) == 0) { |
4895c771 | 789 | struct fib_nh *nh = &FIB_RES_NH(res); |
4895c771 | 790 | |
aee06da6 | 791 | update_or_create_fnhe(nh, fl4->daddr, new_gw, |
deed49df | 792 | 0, jiffies + ip_rt_gc_timeout); |
4895c771 | 793 | } |
ceb33206 DM |
794 | if (kill_route) |
795 | rt->dst.obsolete = DST_OBSOLETE_KILL; | |
e47a185b DM |
796 | call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); |
797 | } | |
798 | neigh_release(n); | |
799 | } | |
800 | return; | |
801 | ||
802 | reject_redirect: | |
803 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
99ee038d DM |
804 | if (IN_DEV_LOG_MARTIANS(in_dev)) { |
805 | const struct iphdr *iph = (const struct iphdr *) skb->data; | |
806 | __be32 daddr = iph->daddr; | |
807 | __be32 saddr = iph->saddr; | |
808 | ||
e47a185b DM |
809 | net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n" |
810 | " Advised path = %pI4 -> %pI4\n", | |
811 | &old_gw, dev->name, &new_gw, | |
812 | &saddr, &daddr); | |
99ee038d | 813 | } |
e47a185b DM |
814 | #endif |
815 | ; | |
816 | } | |
817 | ||
4895c771 DM |
818 | static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb) |
819 | { | |
820 | struct rtable *rt; | |
821 | struct flowi4 fl4; | |
f96ef988 | 822 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
7d995694 | 823 | struct net *net = dev_net(skb->dev); |
f96ef988 MK |
824 | int oif = skb->dev->ifindex; |
825 | u8 tos = RT_TOS(iph->tos); | |
826 | u8 prot = iph->protocol; | |
827 | u32 mark = skb->mark; | |
4895c771 DM |
828 | |
829 | rt = (struct rtable *) dst; | |
830 | ||
7d995694 | 831 | __build_flow_key(net, &fl4, sk, iph, oif, tos, prot, mark, 0); |
ceb33206 | 832 | __ip_do_redirect(rt, skb, &fl4, true); |
4895c771 DM |
833 | } |
834 | ||
1da177e4 LT |
835 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) |
836 | { | |
ee6b9673 | 837 | struct rtable *rt = (struct rtable *)dst; |
1da177e4 LT |
838 | struct dst_entry *ret = dst; |
839 | ||
840 | if (rt) { | |
d11a4dc1 | 841 | if (dst->obsolete > 0) { |
1da177e4 LT |
842 | ip_rt_put(rt); |
843 | ret = NULL; | |
5943634f DM |
844 | } else if ((rt->rt_flags & RTCF_REDIRECTED) || |
845 | rt->dst.expires) { | |
89aef892 | 846 | ip_rt_put(rt); |
1da177e4 LT |
847 | ret = NULL; |
848 | } | |
849 | } | |
850 | return ret; | |
851 | } | |
852 | ||
853 | /* | |
854 | * Algorithm: | |
855 | * 1. The first ip_rt_redirect_number redirects are sent | |
856 | * with exponential backoff, then we stop sending them at all, | |
857 | * assuming that the host ignores our redirects. | |
858 | * 2. If we did not see packets requiring redirects | |
859 | * during ip_rt_redirect_silence, we assume that the host | |
860 | * forgot redirected route and start to send redirects again. | |
861 | * | |
862 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
863 | * in icmp.c. | |
864 | * | |
865 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
866 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
867 | */ | |
868 | ||
869 | void ip_rt_send_redirect(struct sk_buff *skb) | |
870 | { | |
511c3f92 | 871 | struct rtable *rt = skb_rtable(skb); |
30038fc6 | 872 | struct in_device *in_dev; |
92d86829 | 873 | struct inet_peer *peer; |
1d861aa4 | 874 | struct net *net; |
30038fc6 | 875 | int log_martians; |
192132b9 | 876 | int vif; |
1da177e4 | 877 | |
30038fc6 | 878 | rcu_read_lock(); |
d8d1f30b | 879 | in_dev = __in_dev_get_rcu(rt->dst.dev); |
30038fc6 ED |
880 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { |
881 | rcu_read_unlock(); | |
1da177e4 | 882 | return; |
30038fc6 ED |
883 | } |
884 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
385add90 | 885 | vif = l3mdev_master_ifindex_rcu(rt->dst.dev); |
30038fc6 | 886 | rcu_read_unlock(); |
1da177e4 | 887 | |
1d861aa4 | 888 | net = dev_net(rt->dst.dev); |
192132b9 | 889 | peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, vif, 1); |
92d86829 | 890 | if (!peer) { |
e81da0e1 JA |
891 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, |
892 | rt_nexthop(rt, ip_hdr(skb)->daddr)); | |
92d86829 DM |
893 | return; |
894 | } | |
895 | ||
1da177e4 LT |
896 | /* No redirected packets during ip_rt_redirect_silence; |
897 | * reset the algorithm. | |
898 | */ | |
92d86829 DM |
899 | if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) |
900 | peer->rate_tokens = 0; | |
1da177e4 LT |
901 | |
902 | /* Too many ignored redirects; do not send anything | |
d8d1f30b | 903 | * set dst.rate_last to the last seen redirected packet. |
1da177e4 | 904 | */ |
92d86829 DM |
905 | if (peer->rate_tokens >= ip_rt_redirect_number) { |
906 | peer->rate_last = jiffies; | |
1d861aa4 | 907 | goto out_put_peer; |
1da177e4 LT |
908 | } |
909 | ||
910 | /* Check for load limit; set rate_last to the latest sent | |
911 | * redirect. | |
912 | */ | |
92d86829 | 913 | if (peer->rate_tokens == 0 || |
14fb8a76 | 914 | time_after(jiffies, |
92d86829 DM |
915 | (peer->rate_last + |
916 | (ip_rt_redirect_load << peer->rate_tokens)))) { | |
e81da0e1 JA |
917 | __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr); |
918 | ||
919 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw); | |
92d86829 DM |
920 | peer->rate_last = jiffies; |
921 | ++peer->rate_tokens; | |
1da177e4 | 922 | #ifdef CONFIG_IP_ROUTE_VERBOSE |
30038fc6 | 923 | if (log_martians && |
e87cc472 JP |
924 | peer->rate_tokens == ip_rt_redirect_number) |
925 | net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n", | |
92101b3b | 926 | &ip_hdr(skb)->saddr, inet_iif(skb), |
e81da0e1 | 927 | &ip_hdr(skb)->daddr, &gw); |
1da177e4 LT |
928 | #endif |
929 | } | |
1d861aa4 DM |
930 | out_put_peer: |
931 | inet_putpeer(peer); | |
1da177e4 LT |
932 | } |
933 | ||
934 | static int ip_error(struct sk_buff *skb) | |
935 | { | |
251da413 | 936 | struct in_device *in_dev = __in_dev_get_rcu(skb->dev); |
511c3f92 | 937 | struct rtable *rt = skb_rtable(skb); |
92d86829 | 938 | struct inet_peer *peer; |
1da177e4 | 939 | unsigned long now; |
251da413 | 940 | struct net *net; |
92d86829 | 941 | bool send; |
1da177e4 LT |
942 | int code; |
943 | ||
381c759d EB |
944 | /* IP on this device is disabled. */ |
945 | if (!in_dev) | |
946 | goto out; | |
947 | ||
251da413 DM |
948 | net = dev_net(rt->dst.dev); |
949 | if (!IN_DEV_FORWARD(in_dev)) { | |
950 | switch (rt->dst.error) { | |
951 | case EHOSTUNREACH: | |
b45386ef | 952 | __IP_INC_STATS(net, IPSTATS_MIB_INADDRERRORS); |
251da413 DM |
953 | break; |
954 | ||
955 | case ENETUNREACH: | |
b45386ef | 956 | __IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES); |
251da413 DM |
957 | break; |
958 | } | |
959 | goto out; | |
960 | } | |
961 | ||
d8d1f30b | 962 | switch (rt->dst.error) { |
4500ebf8 JP |
963 | case EINVAL: |
964 | default: | |
965 | goto out; | |
966 | case EHOSTUNREACH: | |
967 | code = ICMP_HOST_UNREACH; | |
968 | break; | |
969 | case ENETUNREACH: | |
970 | code = ICMP_NET_UNREACH; | |
b45386ef | 971 | __IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES); |
4500ebf8 JP |
972 | break; |
973 | case EACCES: | |
974 | code = ICMP_PKT_FILTERED; | |
975 | break; | |
1da177e4 LT |
976 | } |
977 | ||
192132b9 | 978 | peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, |
385add90 | 979 | l3mdev_master_ifindex(skb->dev), 1); |
92d86829 DM |
980 | |
981 | send = true; | |
982 | if (peer) { | |
983 | now = jiffies; | |
984 | peer->rate_tokens += now - peer->rate_last; | |
985 | if (peer->rate_tokens > ip_rt_error_burst) | |
986 | peer->rate_tokens = ip_rt_error_burst; | |
987 | peer->rate_last = now; | |
988 | if (peer->rate_tokens >= ip_rt_error_cost) | |
989 | peer->rate_tokens -= ip_rt_error_cost; | |
990 | else | |
991 | send = false; | |
1d861aa4 | 992 | inet_putpeer(peer); |
1da177e4 | 993 | } |
92d86829 DM |
994 | if (send) |
995 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1da177e4 LT |
996 | |
997 | out: kfree_skb(skb); | |
998 | return 0; | |
e905a9ed | 999 | } |
1da177e4 | 1000 | |
d851c12b | 1001 | static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu) |
1da177e4 | 1002 | { |
d851c12b | 1003 | struct dst_entry *dst = &rt->dst; |
4895c771 | 1004 | struct fib_result res; |
2c8cec5c | 1005 | |
fa1e492a SK |
1006 | if (dst_metric_locked(dst, RTAX_MTU)) |
1007 | return; | |
1008 | ||
cb6ccf09 | 1009 | if (ipv4_mtu(dst) < mtu) |
3cdaa5be LW |
1010 | return; |
1011 | ||
5943634f DM |
1012 | if (mtu < ip_rt_min_pmtu) |
1013 | mtu = ip_rt_min_pmtu; | |
2c8cec5c | 1014 | |
f016229e TT |
1015 | if (rt->rt_pmtu == mtu && |
1016 | time_before(jiffies, dst->expires - ip_rt_mtu_expires / 2)) | |
1017 | return; | |
1018 | ||
c5ae7d41 | 1019 | rcu_read_lock(); |
0eeb075f | 1020 | if (fib_lookup(dev_net(dst->dev), fl4, &res, 0) == 0) { |
4895c771 | 1021 | struct fib_nh *nh = &FIB_RES_NH(res); |
4895c771 | 1022 | |
aee06da6 JA |
1023 | update_or_create_fnhe(nh, fl4->daddr, 0, mtu, |
1024 | jiffies + ip_rt_mtu_expires); | |
4895c771 | 1025 | } |
c5ae7d41 | 1026 | rcu_read_unlock(); |
1da177e4 LT |
1027 | } |
1028 | ||
4895c771 DM |
1029 | static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, |
1030 | struct sk_buff *skb, u32 mtu) | |
1031 | { | |
1032 | struct rtable *rt = (struct rtable *) dst; | |
1033 | struct flowi4 fl4; | |
1034 | ||
1035 | ip_rt_build_flow_key(&fl4, sk, skb); | |
d851c12b | 1036 | __ip_rt_update_pmtu(rt, &fl4, mtu); |
4895c771 DM |
1037 | } |
1038 | ||
36393395 DM |
1039 | void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, |
1040 | int oif, u32 mark, u8 protocol, int flow_flags) | |
1041 | { | |
4895c771 | 1042 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
36393395 DM |
1043 | struct flowi4 fl4; |
1044 | struct rtable *rt; | |
1045 | ||
1b3c61dc LC |
1046 | if (!mark) |
1047 | mark = IP4_REPLY_MARK(net, skb->mark); | |
1048 | ||
e2d118a1 | 1049 | __build_flow_key(net, &fl4, NULL, iph, oif, |
4895c771 | 1050 | RT_TOS(iph->tos), protocol, mark, flow_flags); |
36393395 DM |
1051 | rt = __ip_route_output_key(net, &fl4); |
1052 | if (!IS_ERR(rt)) { | |
4895c771 | 1053 | __ip_rt_update_pmtu(rt, &fl4, mtu); |
36393395 DM |
1054 | ip_rt_put(rt); |
1055 | } | |
1056 | } | |
1057 | EXPORT_SYMBOL_GPL(ipv4_update_pmtu); | |
1058 | ||
9cb3a50c | 1059 | static void __ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) |
36393395 | 1060 | { |
4895c771 DM |
1061 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
1062 | struct flowi4 fl4; | |
1063 | struct rtable *rt; | |
36393395 | 1064 | |
e2d118a1 | 1065 | __build_flow_key(sock_net(sk), &fl4, sk, iph, 0, 0, 0, 0, 0); |
1b3c61dc LC |
1066 | |
1067 | if (!fl4.flowi4_mark) | |
1068 | fl4.flowi4_mark = IP4_REPLY_MARK(sock_net(sk), skb->mark); | |
1069 | ||
4895c771 DM |
1070 | rt = __ip_route_output_key(sock_net(sk), &fl4); |
1071 | if (!IS_ERR(rt)) { | |
1072 | __ip_rt_update_pmtu(rt, &fl4, mtu); | |
1073 | ip_rt_put(rt); | |
1074 | } | |
36393395 | 1075 | } |
9cb3a50c SK |
1076 | |
1077 | void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) | |
1078 | { | |
1079 | const struct iphdr *iph = (const struct iphdr *) skb->data; | |
1080 | struct flowi4 fl4; | |
1081 | struct rtable *rt; | |
7f502361 | 1082 | struct dst_entry *odst = NULL; |
b44108db | 1083 | bool new = false; |
e2d118a1 | 1084 | struct net *net = sock_net(sk); |
9cb3a50c SK |
1085 | |
1086 | bh_lock_sock(sk); | |
482fc609 HFS |
1087 | |
1088 | if (!ip_sk_accept_pmtu(sk)) | |
1089 | goto out; | |
1090 | ||
7f502361 | 1091 | odst = sk_dst_get(sk); |
9cb3a50c | 1092 | |
7f502361 | 1093 | if (sock_owned_by_user(sk) || !odst) { |
9cb3a50c SK |
1094 | __ipv4_sk_update_pmtu(skb, sk, mtu); |
1095 | goto out; | |
1096 | } | |
1097 | ||
e2d118a1 | 1098 | __build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0); |
9cb3a50c | 1099 | |
7f502361 | 1100 | rt = (struct rtable *)odst; |
51456b29 | 1101 | if (odst->obsolete && !odst->ops->check(odst, 0)) { |
9cb3a50c SK |
1102 | rt = ip_route_output_flow(sock_net(sk), &fl4, sk); |
1103 | if (IS_ERR(rt)) | |
1104 | goto out; | |
b44108db SK |
1105 | |
1106 | new = true; | |
9cb3a50c SK |
1107 | } |
1108 | ||
0f6c480f | 1109 | __ip_rt_update_pmtu((struct rtable *) xfrm_dst_path(&rt->dst), &fl4, mtu); |
9cb3a50c | 1110 | |
7f502361 | 1111 | if (!dst_check(&rt->dst, 0)) { |
b44108db SK |
1112 | if (new) |
1113 | dst_release(&rt->dst); | |
1114 | ||
9cb3a50c SK |
1115 | rt = ip_route_output_flow(sock_net(sk), &fl4, sk); |
1116 | if (IS_ERR(rt)) | |
1117 | goto out; | |
1118 | ||
b44108db | 1119 | new = true; |
9cb3a50c SK |
1120 | } |
1121 | ||
b44108db | 1122 | if (new) |
7f502361 | 1123 | sk_dst_set(sk, &rt->dst); |
9cb3a50c SK |
1124 | |
1125 | out: | |
1126 | bh_unlock_sock(sk); | |
7f502361 | 1127 | dst_release(odst); |
9cb3a50c | 1128 | } |
36393395 | 1129 | EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu); |
f39925db | 1130 | |
b42597e2 DM |
1131 | void ipv4_redirect(struct sk_buff *skb, struct net *net, |
1132 | int oif, u32 mark, u8 protocol, int flow_flags) | |
1133 | { | |
4895c771 | 1134 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
b42597e2 DM |
1135 | struct flowi4 fl4; |
1136 | struct rtable *rt; | |
1137 | ||
e2d118a1 | 1138 | __build_flow_key(net, &fl4, NULL, iph, oif, |
4895c771 | 1139 | RT_TOS(iph->tos), protocol, mark, flow_flags); |
b42597e2 DM |
1140 | rt = __ip_route_output_key(net, &fl4); |
1141 | if (!IS_ERR(rt)) { | |
ceb33206 | 1142 | __ip_do_redirect(rt, skb, &fl4, false); |
b42597e2 DM |
1143 | ip_rt_put(rt); |
1144 | } | |
1145 | } | |
1146 | EXPORT_SYMBOL_GPL(ipv4_redirect); | |
1147 | ||
1148 | void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk) | |
1149 | { | |
4895c771 DM |
1150 | const struct iphdr *iph = (const struct iphdr *) skb->data; |
1151 | struct flowi4 fl4; | |
1152 | struct rtable *rt; | |
e2d118a1 | 1153 | struct net *net = sock_net(sk); |
b42597e2 | 1154 | |
e2d118a1 LC |
1155 | __build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0); |
1156 | rt = __ip_route_output_key(net, &fl4); | |
4895c771 | 1157 | if (!IS_ERR(rt)) { |
ceb33206 | 1158 | __ip_do_redirect(rt, skb, &fl4, false); |
4895c771 DM |
1159 | ip_rt_put(rt); |
1160 | } | |
b42597e2 DM |
1161 | } |
1162 | EXPORT_SYMBOL_GPL(ipv4_sk_redirect); | |
1163 | ||
efbc368d DM |
1164 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) |
1165 | { | |
1166 | struct rtable *rt = (struct rtable *) dst; | |
1167 | ||
ceb33206 DM |
1168 | /* All IPV4 dsts are created with ->obsolete set to the value |
1169 | * DST_OBSOLETE_FORCE_CHK which forces validation calls down | |
1170 | * into this function always. | |
1171 | * | |
387aa65a TT |
1172 | * When a PMTU/redirect information update invalidates a route, |
1173 | * this is indicated by setting obsolete to DST_OBSOLETE_KILL or | |
1174 | * DST_OBSOLETE_DEAD by dst_free(). | |
ceb33206 | 1175 | */ |
387aa65a | 1176 | if (dst->obsolete != DST_OBSOLETE_FORCE_CHK || rt_is_expired(rt)) |
efbc368d | 1177 | return NULL; |
d11a4dc1 | 1178 | return dst; |
1da177e4 LT |
1179 | } |
1180 | ||
1da177e4 LT |
1181 | static void ipv4_link_failure(struct sk_buff *skb) |
1182 | { | |
1183 | struct rtable *rt; | |
1184 | ||
1185 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1186 | ||
511c3f92 | 1187 | rt = skb_rtable(skb); |
5943634f DM |
1188 | if (rt) |
1189 | dst_set_expires(&rt->dst, 0); | |
1da177e4 LT |
1190 | } |
1191 | ||
ede2059d | 1192 | static int ip_rt_bug(struct net *net, struct sock *sk, struct sk_buff *skb) |
1da177e4 | 1193 | { |
91df42be JP |
1194 | pr_debug("%s: %pI4 -> %pI4, %s\n", |
1195 | __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1196 | skb->dev ? skb->dev->name : "?"); | |
1da177e4 | 1197 | kfree_skb(skb); |
c378a9c0 | 1198 | WARN_ON(1); |
1da177e4 LT |
1199 | return 0; |
1200 | } | |
1201 | ||
1202 | /* | |
1203 | We do not cache source address of outgoing interface, | |
1204 | because it is used only by IP RR, TS and SRR options, | |
1205 | so that it out of fast path. | |
1206 | ||
1207 | BTW remember: "addr" is allowed to be not aligned | |
1208 | in IP options! | |
1209 | */ | |
1210 | ||
8e36360a | 1211 | void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt) |
1da177e4 | 1212 | { |
a61ced5d | 1213 | __be32 src; |
1da177e4 | 1214 | |
c7537967 | 1215 | if (rt_is_output_route(rt)) |
c5be24ff | 1216 | src = ip_hdr(skb)->saddr; |
ebc0ffae | 1217 | else { |
8e36360a DM |
1218 | struct fib_result res; |
1219 | struct flowi4 fl4; | |
1220 | struct iphdr *iph; | |
1221 | ||
1222 | iph = ip_hdr(skb); | |
1223 | ||
1224 | memset(&fl4, 0, sizeof(fl4)); | |
1225 | fl4.daddr = iph->daddr; | |
1226 | fl4.saddr = iph->saddr; | |
b0fe4a31 | 1227 | fl4.flowi4_tos = RT_TOS(iph->tos); |
8e36360a DM |
1228 | fl4.flowi4_oif = rt->dst.dev->ifindex; |
1229 | fl4.flowi4_iif = skb->dev->ifindex; | |
1230 | fl4.flowi4_mark = skb->mark; | |
5e2b61f7 | 1231 | |
ebc0ffae | 1232 | rcu_read_lock(); |
0eeb075f | 1233 | if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0) |
436c3b66 | 1234 | src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res); |
ebc0ffae | 1235 | else |
f8126f1d DM |
1236 | src = inet_select_addr(rt->dst.dev, |
1237 | rt_nexthop(rt, iph->daddr), | |
1238 | RT_SCOPE_UNIVERSE); | |
ebc0ffae ED |
1239 | rcu_read_unlock(); |
1240 | } | |
1da177e4 LT |
1241 | memcpy(addr, &src, 4); |
1242 | } | |
1243 | ||
c7066f70 | 1244 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 LT |
1245 | static void set_class_tag(struct rtable *rt, u32 tag) |
1246 | { | |
d8d1f30b CG |
1247 | if (!(rt->dst.tclassid & 0xFFFF)) |
1248 | rt->dst.tclassid |= tag & 0xFFFF; | |
1249 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1250 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1da177e4 LT |
1251 | } |
1252 | #endif | |
1253 | ||
0dbaee3b DM |
1254 | static unsigned int ipv4_default_advmss(const struct dst_entry *dst) |
1255 | { | |
7ed14d97 | 1256 | unsigned int header_size = sizeof(struct tcphdr) + sizeof(struct iphdr); |
164a5e7a | 1257 | unsigned int advmss = max_t(unsigned int, ipv4_mtu(dst) - header_size, |
7ed14d97 | 1258 | ip_rt_min_advmss); |
0dbaee3b | 1259 | |
7ed14d97 | 1260 | return min(advmss, IPV4_MAX_PMTU - header_size); |
0dbaee3b DM |
1261 | } |
1262 | ||
ebb762f2 | 1263 | static unsigned int ipv4_mtu(const struct dst_entry *dst) |
d33e4553 | 1264 | { |
261663b0 | 1265 | const struct rtable *rt = (const struct rtable *) dst; |
5943634f DM |
1266 | unsigned int mtu = rt->rt_pmtu; |
1267 | ||
98d75c37 | 1268 | if (!mtu || time_after_eq(jiffies, rt->dst.expires)) |
5943634f | 1269 | mtu = dst_metric_raw(dst, RTAX_MTU); |
618f9bc7 | 1270 | |
38d523e2 | 1271 | if (mtu) |
618f9bc7 SK |
1272 | return mtu; |
1273 | ||
c780a049 | 1274 | mtu = READ_ONCE(dst->dev->mtu); |
d33e4553 DM |
1275 | |
1276 | if (unlikely(dst_metric_locked(dst, RTAX_MTU))) { | |
155e8336 | 1277 | if (rt->rt_uses_gateway && mtu > 576) |
d33e4553 DM |
1278 | mtu = 576; |
1279 | } | |
1280 | ||
14972cbd RP |
1281 | mtu = min_t(unsigned int, mtu, IP_MAX_MTU); |
1282 | ||
1283 | return mtu - lwtunnel_headroom(dst->lwtstate, mtu); | |
d33e4553 DM |
1284 | } |
1285 | ||
f2bb4bed | 1286 | static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr) |
4895c771 | 1287 | { |
caa41527 | 1288 | struct fnhe_hash_bucket *hash = rcu_dereference(nh->nh_exceptions); |
4895c771 DM |
1289 | struct fib_nh_exception *fnhe; |
1290 | u32 hval; | |
1291 | ||
f2bb4bed DM |
1292 | if (!hash) |
1293 | return NULL; | |
1294 | ||
d3a25c98 | 1295 | hval = fnhe_hashfun(daddr); |
4895c771 DM |
1296 | |
1297 | for (fnhe = rcu_dereference(hash[hval].chain); fnhe; | |
1298 | fnhe = rcu_dereference(fnhe->fnhe_next)) { | |
f2bb4bed DM |
1299 | if (fnhe->fnhe_daddr == daddr) |
1300 | return fnhe; | |
1301 | } | |
1302 | return NULL; | |
1303 | } | |
aee06da6 | 1304 | |
caacf05e | 1305 | static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe, |
a4c2fd7f | 1306 | __be32 daddr, const bool do_cache) |
f2bb4bed | 1307 | { |
caacf05e DM |
1308 | bool ret = false; |
1309 | ||
c5038a83 | 1310 | spin_lock_bh(&fnhe_lock); |
f2bb4bed | 1311 | |
c5038a83 | 1312 | if (daddr == fnhe->fnhe_daddr) { |
2ffae99d TT |
1313 | struct rtable __rcu **porig; |
1314 | struct rtable *orig; | |
5aad1de5 | 1315 | int genid = fnhe_genid(dev_net(rt->dst.dev)); |
2ffae99d TT |
1316 | |
1317 | if (rt_is_input_route(rt)) | |
1318 | porig = &fnhe->fnhe_rth_input; | |
1319 | else | |
1320 | porig = &fnhe->fnhe_rth_output; | |
1321 | orig = rcu_dereference(*porig); | |
5aad1de5 TT |
1322 | |
1323 | if (fnhe->fnhe_genid != genid) { | |
1324 | fnhe->fnhe_genid = genid; | |
13d82bf5 SK |
1325 | fnhe->fnhe_gw = 0; |
1326 | fnhe->fnhe_pmtu = 0; | |
1327 | fnhe->fnhe_expires = 0; | |
2ffae99d TT |
1328 | fnhe_flush_routes(fnhe); |
1329 | orig = NULL; | |
13d82bf5 | 1330 | } |
387aa65a TT |
1331 | fill_route_from_fnhe(rt, fnhe); |
1332 | if (!rt->rt_gateway) | |
155e8336 | 1333 | rt->rt_gateway = daddr; |
f2bb4bed | 1334 | |
a4c2fd7f | 1335 | if (do_cache) { |
0830106c | 1336 | dst_hold(&rt->dst); |
2ffae99d | 1337 | rcu_assign_pointer(*porig, rt); |
0830106c | 1338 | if (orig) { |
95c47f9c | 1339 | dst_dev_put(&orig->dst); |
0830106c | 1340 | dst_release(&orig->dst); |
0830106c | 1341 | } |
2ffae99d TT |
1342 | ret = true; |
1343 | } | |
c5038a83 DM |
1344 | |
1345 | fnhe->fnhe_stamp = jiffies; | |
c5038a83 DM |
1346 | } |
1347 | spin_unlock_bh(&fnhe_lock); | |
caacf05e DM |
1348 | |
1349 | return ret; | |
54764bb6 ED |
1350 | } |
1351 | ||
caacf05e | 1352 | static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt) |
f2bb4bed | 1353 | { |
d26b3a7c | 1354 | struct rtable *orig, *prev, **p; |
caacf05e | 1355 | bool ret = true; |
f2bb4bed | 1356 | |
d26b3a7c | 1357 | if (rt_is_input_route(rt)) { |
54764bb6 | 1358 | p = (struct rtable **)&nh->nh_rth_input; |
d26b3a7c | 1359 | } else { |
903ceff7 | 1360 | p = (struct rtable **)raw_cpu_ptr(nh->nh_pcpu_rth_output); |
d26b3a7c | 1361 | } |
f2bb4bed DM |
1362 | orig = *p; |
1363 | ||
0830106c WW |
1364 | /* hold dst before doing cmpxchg() to avoid race condition |
1365 | * on this dst | |
1366 | */ | |
1367 | dst_hold(&rt->dst); | |
f2bb4bed DM |
1368 | prev = cmpxchg(p, orig, rt); |
1369 | if (prev == orig) { | |
0830106c | 1370 | if (orig) { |
95c47f9c | 1371 | dst_dev_put(&orig->dst); |
0830106c | 1372 | dst_release(&orig->dst); |
0830106c WW |
1373 | } |
1374 | } else { | |
1375 | dst_release(&rt->dst); | |
caacf05e | 1376 | ret = false; |
0830106c | 1377 | } |
caacf05e DM |
1378 | |
1379 | return ret; | |
1380 | } | |
1381 | ||
5055c371 ED |
1382 | struct uncached_list { |
1383 | spinlock_t lock; | |
1384 | struct list_head head; | |
1385 | }; | |
1386 | ||
1387 | static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt_uncached_list); | |
caacf05e DM |
1388 | |
1389 | static void rt_add_uncached_list(struct rtable *rt) | |
1390 | { | |
5055c371 ED |
1391 | struct uncached_list *ul = raw_cpu_ptr(&rt_uncached_list); |
1392 | ||
1393 | rt->rt_uncached_list = ul; | |
1394 | ||
1395 | spin_lock_bh(&ul->lock); | |
1396 | list_add_tail(&rt->rt_uncached, &ul->head); | |
1397 | spin_unlock_bh(&ul->lock); | |
caacf05e DM |
1398 | } |
1399 | ||
1400 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1401 | { | |
3fb07daf | 1402 | struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); |
caacf05e DM |
1403 | struct rtable *rt = (struct rtable *) dst; |
1404 | ||
9620fef2 | 1405 | if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt)) |
3fb07daf ED |
1406 | kfree(p); |
1407 | ||
78df76a0 | 1408 | if (!list_empty(&rt->rt_uncached)) { |
5055c371 ED |
1409 | struct uncached_list *ul = rt->rt_uncached_list; |
1410 | ||
1411 | spin_lock_bh(&ul->lock); | |
caacf05e | 1412 | list_del(&rt->rt_uncached); |
5055c371 | 1413 | spin_unlock_bh(&ul->lock); |
caacf05e DM |
1414 | } |
1415 | } | |
1416 | ||
1417 | void rt_flush_dev(struct net_device *dev) | |
1418 | { | |
5055c371 ED |
1419 | struct net *net = dev_net(dev); |
1420 | struct rtable *rt; | |
1421 | int cpu; | |
1422 | ||
1423 | for_each_possible_cpu(cpu) { | |
1424 | struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu); | |
caacf05e | 1425 | |
5055c371 ED |
1426 | spin_lock_bh(&ul->lock); |
1427 | list_for_each_entry(rt, &ul->head, rt_uncached) { | |
caacf05e DM |
1428 | if (rt->dst.dev != dev) |
1429 | continue; | |
1430 | rt->dst.dev = net->loopback_dev; | |
1431 | dev_hold(rt->dst.dev); | |
1432 | dev_put(dev); | |
1433 | } | |
5055c371 | 1434 | spin_unlock_bh(&ul->lock); |
4895c771 DM |
1435 | } |
1436 | } | |
1437 | ||
4331debc | 1438 | static bool rt_cache_valid(const struct rtable *rt) |
d2d68ba9 | 1439 | { |
4331debc ED |
1440 | return rt && |
1441 | rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK && | |
1442 | !rt_is_expired(rt); | |
d2d68ba9 DM |
1443 | } |
1444 | ||
f2bb4bed | 1445 | static void rt_set_nexthop(struct rtable *rt, __be32 daddr, |
5e2b61f7 | 1446 | const struct fib_result *res, |
f2bb4bed | 1447 | struct fib_nh_exception *fnhe, |
a4c2fd7f WW |
1448 | struct fib_info *fi, u16 type, u32 itag, |
1449 | const bool do_cache) | |
1da177e4 | 1450 | { |
caacf05e DM |
1451 | bool cached = false; |
1452 | ||
1da177e4 | 1453 | if (fi) { |
4895c771 DM |
1454 | struct fib_nh *nh = &FIB_RES_NH(*res); |
1455 | ||
155e8336 | 1456 | if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) { |
4895c771 | 1457 | rt->rt_gateway = nh->nh_gw; |
155e8336 JA |
1458 | rt->rt_uses_gateway = 1; |
1459 | } | |
3fb07daf ED |
1460 | dst_init_metrics(&rt->dst, fi->fib_metrics->metrics, true); |
1461 | if (fi->fib_metrics != &dst_default_metrics) { | |
1462 | rt->dst._metrics |= DST_METRICS_REFCOUNTED; | |
9620fef2 | 1463 | refcount_inc(&fi->fib_metrics->refcnt); |
3fb07daf | 1464 | } |
c7066f70 | 1465 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f2bb4bed | 1466 | rt->dst.tclassid = nh->nh_tclassid; |
1da177e4 | 1467 | #endif |
61adedf3 | 1468 | rt->dst.lwtstate = lwtstate_get(nh->nh_lwtstate); |
c5038a83 | 1469 | if (unlikely(fnhe)) |
a4c2fd7f WW |
1470 | cached = rt_bind_exception(rt, fnhe, daddr, do_cache); |
1471 | else if (do_cache) | |
caacf05e | 1472 | cached = rt_cache_route(nh, rt); |
155e8336 JA |
1473 | if (unlikely(!cached)) { |
1474 | /* Routes we intend to cache in nexthop exception or | |
1475 | * FIB nexthop have the DST_NOCACHE bit clear. | |
1476 | * However, if we are unsuccessful at storing this | |
1477 | * route into the cache we really need to set it. | |
1478 | */ | |
155e8336 JA |
1479 | if (!rt->rt_gateway) |
1480 | rt->rt_gateway = daddr; | |
1481 | rt_add_uncached_list(rt); | |
1482 | } | |
1483 | } else | |
caacf05e | 1484 | rt_add_uncached_list(rt); |
defb3519 | 1485 | |
c7066f70 | 1486 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1da177e4 | 1487 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
85b91b03 | 1488 | set_class_tag(rt, res->tclassid); |
1da177e4 LT |
1489 | #endif |
1490 | set_class_tag(rt, itag); | |
1491 | #endif | |
1da177e4 LT |
1492 | } |
1493 | ||
9ab179d8 DA |
1494 | struct rtable *rt_dst_alloc(struct net_device *dev, |
1495 | unsigned int flags, u16 type, | |
1496 | bool nopolicy, bool noxfrm, bool will_cache) | |
0c4dcd58 | 1497 | { |
d08c4f35 DA |
1498 | struct rtable *rt; |
1499 | ||
1500 | rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK, | |
a4c2fd7f | 1501 | (will_cache ? 0 : DST_HOST) | |
d08c4f35 | 1502 | (nopolicy ? DST_NOPOLICY : 0) | |
b2a9c0ed | 1503 | (noxfrm ? DST_NOXFRM : 0)); |
d08c4f35 DA |
1504 | |
1505 | if (rt) { | |
1506 | rt->rt_genid = rt_genid_ipv4(dev_net(dev)); | |
1507 | rt->rt_flags = flags; | |
1508 | rt->rt_type = type; | |
1509 | rt->rt_is_input = 0; | |
1510 | rt->rt_iif = 0; | |
1511 | rt->rt_pmtu = 0; | |
1512 | rt->rt_gateway = 0; | |
1513 | rt->rt_uses_gateway = 0; | |
b7503e0c | 1514 | rt->rt_table_id = 0; |
d08c4f35 DA |
1515 | INIT_LIST_HEAD(&rt->rt_uncached); |
1516 | ||
1517 | rt->dst.output = ip_output; | |
1518 | if (flags & RTCF_LOCAL) | |
1519 | rt->dst.input = ip_local_deliver; | |
1520 | } | |
1521 | ||
1522 | return rt; | |
0c4dcd58 | 1523 | } |
9ab179d8 | 1524 | EXPORT_SYMBOL(rt_dst_alloc); |
0c4dcd58 | 1525 | |
96d36220 | 1526 | /* called in rcu_read_lock() section */ |
bc044e8d PA |
1527 | int ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
1528 | u8 tos, struct net_device *dev, | |
1529 | struct in_device *in_dev, u32 *itag) | |
1da177e4 | 1530 | { |
b5f7e755 | 1531 | int err; |
1da177e4 LT |
1532 | |
1533 | /* Primary sanity checks. */ | |
51456b29 | 1534 | if (!in_dev) |
1da177e4 LT |
1535 | return -EINVAL; |
1536 | ||
1e637c74 | 1537 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || |
d0daebc3 | 1538 | skb->protocol != htons(ETH_P_IP)) |
bc044e8d | 1539 | return -EINVAL; |
1da177e4 | 1540 | |
75fea73d | 1541 | if (ipv4_is_loopback(saddr) && !IN_DEV_ROUTE_LOCALNET(in_dev)) |
bc044e8d | 1542 | return -EINVAL; |
d0daebc3 | 1543 | |
f97c1e0c JP |
1544 | if (ipv4_is_zeronet(saddr)) { |
1545 | if (!ipv4_is_local_multicast(daddr)) | |
bc044e8d | 1546 | return -EINVAL; |
b5f7e755 | 1547 | } else { |
9e56e380 | 1548 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, |
bc044e8d | 1549 | in_dev, itag); |
b5f7e755 | 1550 | if (err < 0) |
bc044e8d | 1551 | return err; |
b5f7e755 | 1552 | } |
bc044e8d PA |
1553 | return 0; |
1554 | } | |
1555 | ||
1556 | /* called in rcu_read_lock() section */ | |
1557 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, | |
1558 | u8 tos, struct net_device *dev, int our) | |
1559 | { | |
1560 | struct in_device *in_dev = __in_dev_get_rcu(dev); | |
1561 | unsigned int flags = RTCF_MULTICAST; | |
1562 | struct rtable *rth; | |
1563 | u32 itag = 0; | |
1564 | int err; | |
1565 | ||
1566 | err = ip_mc_validate_source(skb, daddr, saddr, tos, dev, in_dev, &itag); | |
1567 | if (err) | |
1568 | return err; | |
1569 | ||
d08c4f35 DA |
1570 | if (our) |
1571 | flags |= RTCF_LOCAL; | |
1572 | ||
1573 | rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST, | |
f2bb4bed | 1574 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false); |
1da177e4 | 1575 | if (!rth) |
bc044e8d | 1576 | return -ENOBUFS; |
1da177e4 | 1577 | |
cf911662 DM |
1578 | #ifdef CONFIG_IP_ROUTE_CLASSID |
1579 | rth->dst.tclassid = itag; | |
1580 | #endif | |
d8d1f30b | 1581 | rth->dst.output = ip_rt_bug; |
9917e1e8 | 1582 | rth->rt_is_input= 1; |
1da177e4 LT |
1583 | |
1584 | #ifdef CONFIG_IP_MROUTE | |
f97c1e0c | 1585 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) |
d8d1f30b | 1586 | rth->dst.input = ip_mr_input; |
1da177e4 LT |
1587 | #endif |
1588 | RT_CACHE_STAT_INC(in_slow_mc); | |
1589 | ||
89aef892 DM |
1590 | skb_dst_set(skb, &rth->dst); |
1591 | return 0; | |
1da177e4 LT |
1592 | } |
1593 | ||
1594 | ||
1595 | static void ip_handle_martian_source(struct net_device *dev, | |
1596 | struct in_device *in_dev, | |
1597 | struct sk_buff *skb, | |
9e12bb22 AV |
1598 | __be32 daddr, |
1599 | __be32 saddr) | |
1da177e4 LT |
1600 | { |
1601 | RT_CACHE_STAT_INC(in_martian_src); | |
1602 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1603 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
1604 | /* | |
1605 | * RFC1812 recommendation, if source is martian, | |
1606 | * the only hint is MAC header. | |
1607 | */ | |
058bd4d2 | 1608 | pr_warn("martian source %pI4 from %pI4, on dev %s\n", |
673d57e7 | 1609 | &daddr, &saddr, dev->name); |
98e399f8 | 1610 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { |
058bd4d2 JP |
1611 | print_hex_dump(KERN_WARNING, "ll header: ", |
1612 | DUMP_PREFIX_OFFSET, 16, 1, | |
1613 | skb_mac_header(skb), | |
1614 | dev->hard_header_len, true); | |
1da177e4 LT |
1615 | } |
1616 | } | |
1617 | #endif | |
1618 | } | |
1619 | ||
deed49df XL |
1620 | static void ip_del_fnhe(struct fib_nh *nh, __be32 daddr) |
1621 | { | |
1622 | struct fnhe_hash_bucket *hash; | |
1623 | struct fib_nh_exception *fnhe, __rcu **fnhe_p; | |
1624 | u32 hval = fnhe_hashfun(daddr); | |
1625 | ||
1626 | spin_lock_bh(&fnhe_lock); | |
1627 | ||
1628 | hash = rcu_dereference_protected(nh->nh_exceptions, | |
1629 | lockdep_is_held(&fnhe_lock)); | |
1630 | hash += hval; | |
1631 | ||
1632 | fnhe_p = &hash->chain; | |
1633 | fnhe = rcu_dereference_protected(*fnhe_p, lockdep_is_held(&fnhe_lock)); | |
1634 | while (fnhe) { | |
1635 | if (fnhe->fnhe_daddr == daddr) { | |
1636 | rcu_assign_pointer(*fnhe_p, rcu_dereference_protected( | |
1637 | fnhe->fnhe_next, lockdep_is_held(&fnhe_lock))); | |
1638 | fnhe_flush_routes(fnhe); | |
1639 | kfree_rcu(fnhe, rcu); | |
1640 | break; | |
1641 | } | |
1642 | fnhe_p = &fnhe->fnhe_next; | |
1643 | fnhe = rcu_dereference_protected(fnhe->fnhe_next, | |
1644 | lockdep_is_held(&fnhe_lock)); | |
1645 | } | |
1646 | ||
1647 | spin_unlock_bh(&fnhe_lock); | |
1648 | } | |
1649 | ||
efd85700 TG |
1650 | static void set_lwt_redirect(struct rtable *rth) |
1651 | { | |
1652 | if (lwtunnel_output_redirect(rth->dst.lwtstate)) { | |
1653 | rth->dst.lwtstate->orig_output = rth->dst.output; | |
1654 | rth->dst.output = lwtunnel_output; | |
1655 | } | |
1656 | ||
1657 | if (lwtunnel_input_redirect(rth->dst.lwtstate)) { | |
1658 | rth->dst.lwtstate->orig_input = rth->dst.input; | |
1659 | rth->dst.input = lwtunnel_input; | |
1660 | } | |
1661 | } | |
1662 | ||
47360228 | 1663 | /* called in rcu_read_lock() section */ |
5969f71d | 1664 | static int __mkroute_input(struct sk_buff *skb, |
982721f3 | 1665 | const struct fib_result *res, |
5969f71d | 1666 | struct in_device *in_dev, |
c6cffba4 | 1667 | __be32 daddr, __be32 saddr, u32 tos) |
1da177e4 | 1668 | { |
2ffae99d | 1669 | struct fib_nh_exception *fnhe; |
1da177e4 LT |
1670 | struct rtable *rth; |
1671 | int err; | |
1672 | struct in_device *out_dev; | |
d2d68ba9 | 1673 | bool do_cache; |
fbdc0ad0 | 1674 | u32 itag = 0; |
1da177e4 LT |
1675 | |
1676 | /* get a working reference to the output device */ | |
47360228 | 1677 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); |
51456b29 | 1678 | if (!out_dev) { |
e87cc472 | 1679 | net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n"); |
1da177e4 LT |
1680 | return -EINVAL; |
1681 | } | |
1682 | ||
5c04c819 | 1683 | err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res), |
9e56e380 | 1684 | in_dev->dev, in_dev, &itag); |
1da177e4 | 1685 | if (err < 0) { |
e905a9ed | 1686 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, |
1da177e4 | 1687 | saddr); |
e905a9ed | 1688 | |
1da177e4 LT |
1689 | goto cleanup; |
1690 | } | |
1691 | ||
e81da0e1 JA |
1692 | do_cache = res->fi && !itag; |
1693 | if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) && | |
df4d9254 | 1694 | skb->protocol == htons(ETH_P_IP) && |
1da177e4 | 1695 | (IN_DEV_SHARED_MEDIA(out_dev) || |
df4d9254 HFS |
1696 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) |
1697 | IPCB(skb)->flags |= IPSKB_DOREDIRECT; | |
1da177e4 LT |
1698 | |
1699 | if (skb->protocol != htons(ETH_P_IP)) { | |
1700 | /* Not IP (i.e. ARP). Do not create route, if it is | |
1701 | * invalid for proxy arp. DNAT routes are always valid. | |
65324144 JDB |
1702 | * |
1703 | * Proxy arp feature have been extended to allow, ARP | |
1704 | * replies back to the same interface, to support | |
1705 | * Private VLAN switch technologies. See arp.c. | |
1da177e4 | 1706 | */ |
65324144 JDB |
1707 | if (out_dev == in_dev && |
1708 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
1da177e4 LT |
1709 | err = -EINVAL; |
1710 | goto cleanup; | |
1711 | } | |
1712 | } | |
1713 | ||
2ffae99d | 1714 | fnhe = find_exception(&FIB_RES_NH(*res), daddr); |
e81da0e1 | 1715 | if (do_cache) { |
deed49df | 1716 | if (fnhe) { |
2ffae99d | 1717 | rth = rcu_dereference(fnhe->fnhe_rth_input); |
deed49df XL |
1718 | if (rth && rth->dst.expires && |
1719 | time_after(jiffies, rth->dst.expires)) { | |
1720 | ip_del_fnhe(&FIB_RES_NH(*res), daddr); | |
1721 | fnhe = NULL; | |
1722 | } else { | |
1723 | goto rt_cache; | |
1724 | } | |
1725 | } | |
1726 | ||
1727 | rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input); | |
2ffae99d | 1728 | |
deed49df | 1729 | rt_cache: |
e81da0e1 JA |
1730 | if (rt_cache_valid(rth)) { |
1731 | skb_dst_set_noref(skb, &rth->dst); | |
1732 | goto out; | |
d2d68ba9 DM |
1733 | } |
1734 | } | |
f2bb4bed | 1735 | |
d08c4f35 | 1736 | rth = rt_dst_alloc(out_dev->dev, 0, res->type, |
5c1e6aa3 | 1737 | IN_DEV_CONF_GET(in_dev, NOPOLICY), |
d2d68ba9 | 1738 | IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache); |
1da177e4 LT |
1739 | if (!rth) { |
1740 | err = -ENOBUFS; | |
1741 | goto cleanup; | |
1742 | } | |
1743 | ||
9917e1e8 | 1744 | rth->rt_is_input = 1; |
b7503e0c DA |
1745 | if (res->table) |
1746 | rth->rt_table_id = res->table->tb_id; | |
a6254864 | 1747 | RT_CACHE_STAT_INC(in_slow_tot); |
1da177e4 | 1748 | |
d8d1f30b | 1749 | rth->dst.input = ip_forward; |
1da177e4 | 1750 | |
a4c2fd7f WW |
1751 | rt_set_nexthop(rth, daddr, res, fnhe, res->fi, res->type, itag, |
1752 | do_cache); | |
efd85700 | 1753 | set_lwt_redirect(rth); |
c6cffba4 | 1754 | skb_dst_set(skb, &rth->dst); |
d2d68ba9 | 1755 | out: |
1da177e4 LT |
1756 | err = 0; |
1757 | cleanup: | |
1da177e4 | 1758 | return err; |
e905a9ed | 1759 | } |
1da177e4 | 1760 | |
79a13159 | 1761 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
79a13159 | 1762 | /* To make ICMP packets follow the right flow, the multipath hash is |
bf4e0a3d | 1763 | * calculated from the inner IP addresses. |
79a13159 | 1764 | */ |
bf4e0a3d NA |
1765 | static void ip_multipath_l3_keys(const struct sk_buff *skb, |
1766 | struct flow_keys *hash_keys) | |
79a13159 PN |
1767 | { |
1768 | const struct iphdr *outer_iph = ip_hdr(skb); | |
bf4e0a3d | 1769 | const struct iphdr *inner_iph; |
79a13159 PN |
1770 | const struct icmphdr *icmph; |
1771 | struct iphdr _inner_iph; | |
bf4e0a3d NA |
1772 | struct icmphdr _icmph; |
1773 | ||
1774 | hash_keys->addrs.v4addrs.src = outer_iph->saddr; | |
1775 | hash_keys->addrs.v4addrs.dst = outer_iph->daddr; | |
1776 | if (likely(outer_iph->protocol != IPPROTO_ICMP)) | |
1777 | return; | |
79a13159 PN |
1778 | |
1779 | if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0)) | |
bf4e0a3d | 1780 | return; |
79a13159 PN |
1781 | |
1782 | icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph), | |
1783 | &_icmph); | |
1784 | if (!icmph) | |
bf4e0a3d | 1785 | return; |
79a13159 PN |
1786 | |
1787 | if (icmph->type != ICMP_DEST_UNREACH && | |
1788 | icmph->type != ICMP_REDIRECT && | |
1789 | icmph->type != ICMP_TIME_EXCEEDED && | |
bf4e0a3d NA |
1790 | icmph->type != ICMP_PARAMETERPROB) |
1791 | return; | |
79a13159 PN |
1792 | |
1793 | inner_iph = skb_header_pointer(skb, | |
1794 | outer_iph->ihl * 4 + sizeof(_icmph), | |
1795 | sizeof(_inner_iph), &_inner_iph); | |
1796 | if (!inner_iph) | |
bf4e0a3d NA |
1797 | return; |
1798 | hash_keys->addrs.v4addrs.src = inner_iph->saddr; | |
1799 | hash_keys->addrs.v4addrs.dst = inner_iph->daddr; | |
1800 | } | |
79a13159 | 1801 | |
bf4e0a3d NA |
1802 | /* if skb is set it will be used and fl4 can be NULL */ |
1803 | int fib_multipath_hash(const struct fib_info *fi, const struct flowi4 *fl4, | |
1804 | const struct sk_buff *skb) | |
1805 | { | |
1806 | struct net *net = fi->fib_net; | |
1807 | struct flow_keys hash_keys; | |
1808 | u32 mhash; | |
79a13159 | 1809 | |
bf4e0a3d NA |
1810 | switch (net->ipv4.sysctl_fib_multipath_hash_policy) { |
1811 | case 0: | |
1812 | memset(&hash_keys, 0, sizeof(hash_keys)); | |
1813 | hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; | |
1814 | if (skb) { | |
1815 | ip_multipath_l3_keys(skb, &hash_keys); | |
1816 | } else { | |
1817 | hash_keys.addrs.v4addrs.src = fl4->saddr; | |
1818 | hash_keys.addrs.v4addrs.dst = fl4->daddr; | |
1819 | } | |
1820 | break; | |
1821 | case 1: | |
1822 | /* skb is currently provided only when forwarding */ | |
1823 | if (skb) { | |
1824 | unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP; | |
1825 | struct flow_keys keys; | |
1826 | ||
1827 | /* short-circuit if we already have L4 hash present */ | |
1828 | if (skb->l4_hash) | |
1829 | return skb_get_hash_raw(skb) >> 1; | |
1830 | memset(&hash_keys, 0, sizeof(hash_keys)); | |
1831 | skb_flow_dissect_flow_keys(skb, &keys, flag); | |
1832 | hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src; | |
1833 | hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst; | |
1834 | hash_keys.ports.src = keys.ports.src; | |
1835 | hash_keys.ports.dst = keys.ports.dst; | |
1836 | hash_keys.basic.ip_proto = keys.basic.ip_proto; | |
1837 | } else { | |
1838 | memset(&hash_keys, 0, sizeof(hash_keys)); | |
1839 | hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; | |
1840 | hash_keys.addrs.v4addrs.src = fl4->saddr; | |
1841 | hash_keys.addrs.v4addrs.dst = fl4->daddr; | |
1842 | hash_keys.ports.src = fl4->fl4_sport; | |
1843 | hash_keys.ports.dst = fl4->fl4_dport; | |
1844 | hash_keys.basic.ip_proto = fl4->flowi4_proto; | |
1845 | } | |
1846 | break; | |
1847 | } | |
1848 | mhash = flow_hash_from_keys(&hash_keys); | |
79a13159 | 1849 | |
bf4e0a3d NA |
1850 | return mhash >> 1; |
1851 | } | |
1852 | EXPORT_SYMBOL_GPL(fib_multipath_hash); | |
79a13159 PN |
1853 | #endif /* CONFIG_IP_ROUTE_MULTIPATH */ |
1854 | ||
5969f71d SH |
1855 | static int ip_mkroute_input(struct sk_buff *skb, |
1856 | struct fib_result *res, | |
5969f71d SH |
1857 | struct in_device *in_dev, |
1858 | __be32 daddr, __be32 saddr, u32 tos) | |
1da177e4 | 1859 | { |
1da177e4 | 1860 | #ifdef CONFIG_IP_ROUTE_MULTIPATH |
0e884c78 | 1861 | if (res->fi && res->fi->fib_nhs > 1) { |
bf4e0a3d | 1862 | int h = fib_multipath_hash(res->fi, NULL, skb); |
0e884c78 | 1863 | |
0e884c78 PN |
1864 | fib_select_multipath(res, h); |
1865 | } | |
1da177e4 LT |
1866 | #endif |
1867 | ||
1868 | /* create a routing cache entry */ | |
c6cffba4 | 1869 | return __mkroute_input(skb, res, in_dev, daddr, saddr, tos); |
1da177e4 LT |
1870 | } |
1871 | ||
1da177e4 LT |
1872 | /* |
1873 | * NOTE. We drop all the packets that has local source | |
1874 | * addresses, because every properly looped back packet | |
1875 | * must have correct destination already attached by output routine. | |
1876 | * | |
1877 | * Such approach solves two big problems: | |
1878 | * 1. Not simplex devices are handled properly. | |
1879 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
ebc0ffae | 1880 | * called with rcu_read_lock() |
1da177e4 LT |
1881 | */ |
1882 | ||
9e12bb22 | 1883 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
5510cdf7 DA |
1884 | u8 tos, struct net_device *dev, |
1885 | struct fib_result *res) | |
1da177e4 | 1886 | { |
96d36220 | 1887 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
1b7179d3 | 1888 | struct ip_tunnel_info *tun_info; |
68a5e3dd | 1889 | struct flowi4 fl4; |
95c96174 | 1890 | unsigned int flags = 0; |
1da177e4 | 1891 | u32 itag = 0; |
95c96174 | 1892 | struct rtable *rth; |
1da177e4 | 1893 | int err = -EINVAL; |
5e73ea1a | 1894 | struct net *net = dev_net(dev); |
d2d68ba9 | 1895 | bool do_cache; |
1da177e4 LT |
1896 | |
1897 | /* IP on this device is disabled. */ | |
1898 | ||
1899 | if (!in_dev) | |
1900 | goto out; | |
1901 | ||
1902 | /* Check for the most weird martians, which can be not detected | |
1903 | by fib_lookup. | |
1904 | */ | |
1905 | ||
61adedf3 | 1906 | tun_info = skb_tunnel_info(skb); |
46fa062a | 1907 | if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX)) |
1b7179d3 TG |
1908 | fl4.flowi4_tun_key.tun_id = tun_info->key.tun_id; |
1909 | else | |
1910 | fl4.flowi4_tun_key.tun_id = 0; | |
f38a9eb1 TG |
1911 | skb_dst_drop(skb); |
1912 | ||
d0daebc3 | 1913 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) |
1da177e4 LT |
1914 | goto martian_source; |
1915 | ||
5510cdf7 DA |
1916 | res->fi = NULL; |
1917 | res->table = NULL; | |
27a954bd | 1918 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) |
1da177e4 LT |
1919 | goto brd_input; |
1920 | ||
1921 | /* Accept zero addresses only to limited broadcast; | |
1922 | * I even do not know to fix it or not. Waiting for complains :-) | |
1923 | */ | |
f97c1e0c | 1924 | if (ipv4_is_zeronet(saddr)) |
1da177e4 LT |
1925 | goto martian_source; |
1926 | ||
d0daebc3 | 1927 | if (ipv4_is_zeronet(daddr)) |
1da177e4 LT |
1928 | goto martian_destination; |
1929 | ||
9eb43e76 ED |
1930 | /* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(), |
1931 | * and call it once if daddr or/and saddr are loopback addresses | |
1932 | */ | |
1933 | if (ipv4_is_loopback(daddr)) { | |
1934 | if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) | |
d0daebc3 | 1935 | goto martian_destination; |
9eb43e76 ED |
1936 | } else if (ipv4_is_loopback(saddr)) { |
1937 | if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) | |
d0daebc3 TG |
1938 | goto martian_source; |
1939 | } | |
1940 | ||
1da177e4 LT |
1941 | /* |
1942 | * Now we are ready to route packet. | |
1943 | */ | |
68a5e3dd | 1944 | fl4.flowi4_oif = 0; |
e0d56fdd | 1945 | fl4.flowi4_iif = dev->ifindex; |
68a5e3dd DM |
1946 | fl4.flowi4_mark = skb->mark; |
1947 | fl4.flowi4_tos = tos; | |
1948 | fl4.flowi4_scope = RT_SCOPE_UNIVERSE; | |
b84f7878 | 1949 | fl4.flowi4_flags = 0; |
68a5e3dd DM |
1950 | fl4.daddr = daddr; |
1951 | fl4.saddr = saddr; | |
8bcfd092 | 1952 | fl4.flowi4_uid = sock_net_uid(net, NULL); |
5510cdf7 | 1953 | err = fib_lookup(net, &fl4, res, 0); |
cd0f0b95 DJ |
1954 | if (err != 0) { |
1955 | if (!IN_DEV_FORWARD(in_dev)) | |
1956 | err = -EHOSTUNREACH; | |
1da177e4 | 1957 | goto no_route; |
cd0f0b95 | 1958 | } |
1da177e4 | 1959 | |
5510cdf7 | 1960 | if (res->type == RTN_BROADCAST) |
1da177e4 LT |
1961 | goto brd_input; |
1962 | ||
5510cdf7 | 1963 | if (res->type == RTN_LOCAL) { |
5c04c819 | 1964 | err = fib_validate_source(skb, saddr, daddr, tos, |
0d5edc68 | 1965 | 0, dev, in_dev, &itag); |
b5f7e755 | 1966 | if (err < 0) |
0d753960 | 1967 | goto martian_source; |
1da177e4 LT |
1968 | goto local_input; |
1969 | } | |
1970 | ||
cd0f0b95 DJ |
1971 | if (!IN_DEV_FORWARD(in_dev)) { |
1972 | err = -EHOSTUNREACH; | |
251da413 | 1973 | goto no_route; |
cd0f0b95 | 1974 | } |
5510cdf7 | 1975 | if (res->type != RTN_UNICAST) |
1da177e4 LT |
1976 | goto martian_destination; |
1977 | ||
5510cdf7 | 1978 | err = ip_mkroute_input(skb, res, in_dev, daddr, saddr, tos); |
1da177e4 LT |
1979 | out: return err; |
1980 | ||
1981 | brd_input: | |
1982 | if (skb->protocol != htons(ETH_P_IP)) | |
1983 | goto e_inval; | |
1984 | ||
41347dcd | 1985 | if (!ipv4_is_zeronet(saddr)) { |
9e56e380 DM |
1986 | err = fib_validate_source(skb, saddr, 0, tos, 0, dev, |
1987 | in_dev, &itag); | |
1da177e4 | 1988 | if (err < 0) |
0d753960 | 1989 | goto martian_source; |
1da177e4 LT |
1990 | } |
1991 | flags |= RTCF_BROADCAST; | |
5510cdf7 | 1992 | res->type = RTN_BROADCAST; |
1da177e4 LT |
1993 | RT_CACHE_STAT_INC(in_brd); |
1994 | ||
1995 | local_input: | |
d2d68ba9 | 1996 | do_cache = false; |
5510cdf7 | 1997 | if (res->fi) { |
fe3edf45 | 1998 | if (!itag) { |
5510cdf7 | 1999 | rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input); |
d2d68ba9 | 2000 | if (rt_cache_valid(rth)) { |
c6cffba4 DM |
2001 | skb_dst_set_noref(skb, &rth->dst); |
2002 | err = 0; | |
2003 | goto out; | |
d2d68ba9 DM |
2004 | } |
2005 | do_cache = true; | |
2006 | } | |
2007 | } | |
2008 | ||
f5a0aab8 | 2009 | rth = rt_dst_alloc(l3mdev_master_dev_rcu(dev) ? : net->loopback_dev, |
5510cdf7 | 2010 | flags | RTCF_LOCAL, res->type, |
d2d68ba9 | 2011 | IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache); |
1da177e4 LT |
2012 | if (!rth) |
2013 | goto e_nobufs; | |
2014 | ||
d8d1f30b | 2015 | rth->dst.output= ip_rt_bug; |
cf911662 DM |
2016 | #ifdef CONFIG_IP_ROUTE_CLASSID |
2017 | rth->dst.tclassid = itag; | |
2018 | #endif | |
9917e1e8 | 2019 | rth->rt_is_input = 1; |
5510cdf7 DA |
2020 | if (res->table) |
2021 | rth->rt_table_id = res->table->tb_id; | |
571e7226 | 2022 | |
a6254864 | 2023 | RT_CACHE_STAT_INC(in_slow_tot); |
5510cdf7 | 2024 | if (res->type == RTN_UNREACHABLE) { |
d8d1f30b CG |
2025 | rth->dst.input= ip_error; |
2026 | rth->dst.error= -err; | |
1da177e4 LT |
2027 | rth->rt_flags &= ~RTCF_LOCAL; |
2028 | } | |
efd85700 | 2029 | |
dcdfdf56 | 2030 | if (do_cache) { |
5510cdf7 | 2031 | struct fib_nh *nh = &FIB_RES_NH(*res); |
efd85700 TG |
2032 | |
2033 | rth->dst.lwtstate = lwtstate_get(nh->nh_lwtstate); | |
2034 | if (lwtunnel_input_redirect(rth->dst.lwtstate)) { | |
2035 | WARN_ON(rth->dst.input == lwtunnel_input); | |
2036 | rth->dst.lwtstate->orig_input = rth->dst.input; | |
2037 | rth->dst.input = lwtunnel_input; | |
2038 | } | |
2039 | ||
a4c2fd7f | 2040 | if (unlikely(!rt_cache_route(nh, rth))) |
dcdfdf56 | 2041 | rt_add_uncached_list(rth); |
dcdfdf56 | 2042 | } |
89aef892 | 2043 | skb_dst_set(skb, &rth->dst); |
b23dd4fe | 2044 | err = 0; |
ebc0ffae | 2045 | goto out; |
1da177e4 LT |
2046 | |
2047 | no_route: | |
2048 | RT_CACHE_STAT_INC(in_no_route); | |
5510cdf7 DA |
2049 | res->type = RTN_UNREACHABLE; |
2050 | res->fi = NULL; | |
2051 | res->table = NULL; | |
1da177e4 LT |
2052 | goto local_input; |
2053 | ||
2054 | /* | |
2055 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2056 | */ | |
2057 | martian_destination: | |
2058 | RT_CACHE_STAT_INC(in_martian_dst); | |
2059 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
e87cc472 JP |
2060 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
2061 | net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n", | |
2062 | &daddr, &saddr, dev->name); | |
1da177e4 | 2063 | #endif |
2c2910a4 | 2064 | |
1da177e4 LT |
2065 | e_inval: |
2066 | err = -EINVAL; | |
ebc0ffae | 2067 | goto out; |
1da177e4 LT |
2068 | |
2069 | e_nobufs: | |
2070 | err = -ENOBUFS; | |
ebc0ffae | 2071 | goto out; |
1da177e4 LT |
2072 | |
2073 | martian_source: | |
2074 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); | |
ebc0ffae | 2075 | goto out; |
1da177e4 LT |
2076 | } |
2077 | ||
c6cffba4 DM |
2078 | int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr, |
2079 | u8 tos, struct net_device *dev) | |
1da177e4 | 2080 | { |
5510cdf7 DA |
2081 | struct fib_result res; |
2082 | int err; | |
1da177e4 | 2083 | |
6e28099d | 2084 | tos &= IPTOS_RT_MASK; |
96d36220 | 2085 | rcu_read_lock(); |
5510cdf7 DA |
2086 | err = ip_route_input_rcu(skb, daddr, saddr, tos, dev, &res); |
2087 | rcu_read_unlock(); | |
96d36220 | 2088 | |
5510cdf7 DA |
2089 | return err; |
2090 | } | |
2091 | EXPORT_SYMBOL(ip_route_input_noref); | |
2092 | ||
2093 | /* called with rcu_read_lock held */ | |
2094 | int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr, | |
2095 | u8 tos, struct net_device *dev, struct fib_result *res) | |
2096 | { | |
1da177e4 LT |
2097 | /* Multicast recognition logic is moved from route cache to here. |
2098 | The problem was that too many Ethernet cards have broken/missing | |
2099 | hardware multicast filters :-( As result the host on multicasting | |
2100 | network acquires a lot of useless route cache entries, sort of | |
2101 | SDR messages from all the world. Now we try to get rid of them. | |
2102 | Really, provided software IP multicast filter is organized | |
2103 | reasonably (at least, hashed), it does not result in a slowdown | |
2104 | comparing with route cache reject entries. | |
2105 | Note, that multicast routers are not affected, because | |
2106 | route cache entry is created eventually. | |
2107 | */ | |
f97c1e0c | 2108 | if (ipv4_is_multicast(daddr)) { |
96d36220 | 2109 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
e58e4159 | 2110 | int our = 0; |
5510cdf7 | 2111 | int err = -EINVAL; |
1da177e4 | 2112 | |
e58e4159 DA |
2113 | if (in_dev) |
2114 | our = ip_check_mc_rcu(in_dev, daddr, saddr, | |
2115 | ip_hdr(skb)->protocol); | |
2116 | ||
2117 | /* check l3 master if no match yet */ | |
2118 | if ((!in_dev || !our) && netif_is_l3_slave(dev)) { | |
2119 | struct in_device *l3_in_dev; | |
2120 | ||
2121 | l3_in_dev = __in_dev_get_rcu(skb->dev); | |
2122 | if (l3_in_dev) | |
2123 | our = ip_check_mc_rcu(l3_in_dev, daddr, saddr, | |
2124 | ip_hdr(skb)->protocol); | |
2125 | } | |
2126 | ||
e58e4159 | 2127 | if (our |
1da177e4 | 2128 | #ifdef CONFIG_IP_MROUTE |
e58e4159 DA |
2129 | || |
2130 | (!ipv4_is_local_multicast(daddr) && | |
2131 | IN_DEV_MFORWARD(in_dev)) | |
1da177e4 | 2132 | #endif |
e58e4159 | 2133 | ) { |
5510cdf7 | 2134 | err = ip_route_input_mc(skb, daddr, saddr, |
e58e4159 | 2135 | tos, dev, our); |
1da177e4 | 2136 | } |
5510cdf7 | 2137 | return err; |
1da177e4 | 2138 | } |
5510cdf7 DA |
2139 | |
2140 | return ip_route_input_slow(skb, daddr, saddr, tos, dev, res); | |
1da177e4 LT |
2141 | } |
2142 | ||
ebc0ffae | 2143 | /* called with rcu_read_lock() */ |
982721f3 | 2144 | static struct rtable *__mkroute_output(const struct fib_result *res, |
1a00fee4 | 2145 | const struct flowi4 *fl4, int orig_oif, |
f61759e6 | 2146 | struct net_device *dev_out, |
5ada5527 | 2147 | unsigned int flags) |
1da177e4 | 2148 | { |
982721f3 | 2149 | struct fib_info *fi = res->fi; |
f2bb4bed | 2150 | struct fib_nh_exception *fnhe; |
5ada5527 | 2151 | struct in_device *in_dev; |
982721f3 | 2152 | u16 type = res->type; |
5ada5527 | 2153 | struct rtable *rth; |
c92b9655 | 2154 | bool do_cache; |
1da177e4 | 2155 | |
d0daebc3 TG |
2156 | in_dev = __in_dev_get_rcu(dev_out); |
2157 | if (!in_dev) | |
5ada5527 | 2158 | return ERR_PTR(-EINVAL); |
1da177e4 | 2159 | |
d0daebc3 | 2160 | if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) |
5f02ce24 DA |
2161 | if (ipv4_is_loopback(fl4->saddr) && |
2162 | !(dev_out->flags & IFF_LOOPBACK) && | |
2163 | !netif_is_l3_master(dev_out)) | |
d0daebc3 TG |
2164 | return ERR_PTR(-EINVAL); |
2165 | ||
68a5e3dd | 2166 | if (ipv4_is_lbcast(fl4->daddr)) |
982721f3 | 2167 | type = RTN_BROADCAST; |
68a5e3dd | 2168 | else if (ipv4_is_multicast(fl4->daddr)) |
982721f3 | 2169 | type = RTN_MULTICAST; |
68a5e3dd | 2170 | else if (ipv4_is_zeronet(fl4->daddr)) |
5ada5527 | 2171 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
2172 | |
2173 | if (dev_out->flags & IFF_LOOPBACK) | |
2174 | flags |= RTCF_LOCAL; | |
2175 | ||
63617421 | 2176 | do_cache = true; |
982721f3 | 2177 | if (type == RTN_BROADCAST) { |
1da177e4 | 2178 | flags |= RTCF_BROADCAST | RTCF_LOCAL; |
982721f3 DM |
2179 | fi = NULL; |
2180 | } else if (type == RTN_MULTICAST) { | |
dd28d1a0 | 2181 | flags |= RTCF_MULTICAST | RTCF_LOCAL; |
813b3b5d DM |
2182 | if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr, |
2183 | fl4->flowi4_proto)) | |
1da177e4 | 2184 | flags &= ~RTCF_LOCAL; |
63617421 JA |
2185 | else |
2186 | do_cache = false; | |
1da177e4 | 2187 | /* If multicast route do not exist use |
dd28d1a0 ED |
2188 | * default one, but do not gateway in this case. |
2189 | * Yes, it is hack. | |
1da177e4 | 2190 | */ |
982721f3 DM |
2191 | if (fi && res->prefixlen < 4) |
2192 | fi = NULL; | |
d6d5e999 CF |
2193 | } else if ((type == RTN_LOCAL) && (orig_oif != 0) && |
2194 | (orig_oif != dev_out->ifindex)) { | |
2195 | /* For local routes that require a particular output interface | |
2196 | * we do not want to cache the result. Caching the result | |
2197 | * causes incorrect behaviour when there are multiple source | |
2198 | * addresses on the interface, the end result being that if the | |
2199 | * intended recipient is waiting on that interface for the | |
2200 | * packet he won't receive it because it will be delivered on | |
2201 | * the loopback interface and the IP_PKTINFO ipi_ifindex will | |
2202 | * be set to the loopback interface as well. | |
2203 | */ | |
2204 | fi = NULL; | |
1da177e4 LT |
2205 | } |
2206 | ||
f2bb4bed | 2207 | fnhe = NULL; |
63617421 JA |
2208 | do_cache &= fi != NULL; |
2209 | if (do_cache) { | |
c5038a83 | 2210 | struct rtable __rcu **prth; |
c92b9655 | 2211 | struct fib_nh *nh = &FIB_RES_NH(*res); |
d26b3a7c | 2212 | |
c92b9655 | 2213 | fnhe = find_exception(nh, fl4->daddr); |
deed49df | 2214 | if (fnhe) { |
2ffae99d | 2215 | prth = &fnhe->fnhe_rth_output; |
deed49df XL |
2216 | rth = rcu_dereference(*prth); |
2217 | if (rth && rth->dst.expires && | |
2218 | time_after(jiffies, rth->dst.expires)) { | |
2219 | ip_del_fnhe(nh, fl4->daddr); | |
2220 | fnhe = NULL; | |
2221 | } else { | |
2222 | goto rt_cache; | |
c92b9655 | 2223 | } |
c92b9655 | 2224 | } |
deed49df XL |
2225 | |
2226 | if (unlikely(fl4->flowi4_flags & | |
2227 | FLOWI_FLAG_KNOWN_NH && | |
2228 | !(nh->nh_gw && | |
2229 | nh->nh_scope == RT_SCOPE_LINK))) { | |
2230 | do_cache = false; | |
2231 | goto add; | |
2232 | } | |
2233 | prth = raw_cpu_ptr(nh->nh_pcpu_rth_output); | |
c5038a83 | 2234 | rth = rcu_dereference(*prth); |
deed49df XL |
2235 | |
2236 | rt_cache: | |
9df16efa | 2237 | if (rt_cache_valid(rth) && dst_hold_safe(&rth->dst)) |
c5038a83 | 2238 | return rth; |
f2bb4bed | 2239 | } |
c92b9655 JA |
2240 | |
2241 | add: | |
d08c4f35 | 2242 | rth = rt_dst_alloc(dev_out, flags, type, |
5c1e6aa3 | 2243 | IN_DEV_CONF_GET(in_dev, NOPOLICY), |
f2bb4bed | 2244 | IN_DEV_CONF_GET(in_dev, NOXFRM), |
c92b9655 | 2245 | do_cache); |
8391d07b | 2246 | if (!rth) |
5ada5527 | 2247 | return ERR_PTR(-ENOBUFS); |
8391d07b | 2248 | |
9438c871 | 2249 | rth->rt_iif = orig_oif; |
b7503e0c DA |
2250 | if (res->table) |
2251 | rth->rt_table_id = res->table->tb_id; | |
2252 | ||
1da177e4 LT |
2253 | RT_CACHE_STAT_INC(out_slow_tot); |
2254 | ||
1da177e4 | 2255 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { |
e905a9ed | 2256 | if (flags & RTCF_LOCAL && |
1da177e4 | 2257 | !(dev_out->flags & IFF_LOOPBACK)) { |
d8d1f30b | 2258 | rth->dst.output = ip_mc_output; |
1da177e4 LT |
2259 | RT_CACHE_STAT_INC(out_slow_mc); |
2260 | } | |
2261 | #ifdef CONFIG_IP_MROUTE | |
982721f3 | 2262 | if (type == RTN_MULTICAST) { |
1da177e4 | 2263 | if (IN_DEV_MFORWARD(in_dev) && |
813b3b5d | 2264 | !ipv4_is_local_multicast(fl4->daddr)) { |
d8d1f30b CG |
2265 | rth->dst.input = ip_mr_input; |
2266 | rth->dst.output = ip_mc_output; | |
1da177e4 LT |
2267 | } |
2268 | } | |
2269 | #endif | |
2270 | } | |
2271 | ||
a4c2fd7f | 2272 | rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0, do_cache); |
efd85700 | 2273 | set_lwt_redirect(rth); |
1da177e4 | 2274 | |
5ada5527 | 2275 | return rth; |
1da177e4 LT |
2276 | } |
2277 | ||
1da177e4 LT |
2278 | /* |
2279 | * Major route resolver routine. | |
2280 | */ | |
2281 | ||
3abd1ade DA |
2282 | struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *fl4, |
2283 | const struct sk_buff *skb) | |
1da177e4 | 2284 | { |
f61759e6 | 2285 | __u8 tos = RT_FL_TOS(fl4); |
813b3b5d | 2286 | struct fib_result res; |
5ada5527 | 2287 | struct rtable *rth; |
1da177e4 | 2288 | |
85b91b03 | 2289 | res.tclassid = 0; |
1da177e4 | 2290 | res.fi = NULL; |
8b96d22d | 2291 | res.table = NULL; |
1da177e4 | 2292 | |
1fb9489b | 2293 | fl4->flowi4_iif = LOOPBACK_IFINDEX; |
813b3b5d DM |
2294 | fl4->flowi4_tos = tos & IPTOS_RT_MASK; |
2295 | fl4->flowi4_scope = ((tos & RTO_ONLINK) ? | |
2296 | RT_SCOPE_LINK : RT_SCOPE_UNIVERSE); | |
44713b67 | 2297 | |
010c2708 | 2298 | rcu_read_lock(); |
3abd1ade DA |
2299 | rth = ip_route_output_key_hash_rcu(net, fl4, &res, skb); |
2300 | rcu_read_unlock(); | |
2301 | ||
2302 | return rth; | |
2303 | } | |
2304 | EXPORT_SYMBOL_GPL(ip_route_output_key_hash); | |
2305 | ||
2306 | struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4 *fl4, | |
2307 | struct fib_result *res, | |
2308 | const struct sk_buff *skb) | |
2309 | { | |
2310 | struct net_device *dev_out = NULL; | |
2311 | int orig_oif = fl4->flowi4_oif; | |
2312 | unsigned int flags = 0; | |
2313 | struct rtable *rth; | |
2314 | int err = -ENETUNREACH; | |
2315 | ||
813b3b5d | 2316 | if (fl4->saddr) { |
b23dd4fe | 2317 | rth = ERR_PTR(-EINVAL); |
813b3b5d DM |
2318 | if (ipv4_is_multicast(fl4->saddr) || |
2319 | ipv4_is_lbcast(fl4->saddr) || | |
2320 | ipv4_is_zeronet(fl4->saddr)) | |
1da177e4 LT |
2321 | goto out; |
2322 | ||
1da177e4 LT |
2323 | /* I removed check for oif == dev_out->oif here. |
2324 | It was wrong for two reasons: | |
1ab35276 DL |
2325 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr |
2326 | is assigned to multiple interfaces. | |
1da177e4 LT |
2327 | 2. Moreover, we are allowed to send packets with saddr |
2328 | of another iface. --ANK | |
2329 | */ | |
2330 | ||
813b3b5d DM |
2331 | if (fl4->flowi4_oif == 0 && |
2332 | (ipv4_is_multicast(fl4->daddr) || | |
2333 | ipv4_is_lbcast(fl4->daddr))) { | |
a210d01a | 2334 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2335 | dev_out = __ip_dev_find(net, fl4->saddr, false); |
51456b29 | 2336 | if (!dev_out) |
a210d01a JA |
2337 | goto out; |
2338 | ||
1da177e4 LT |
2339 | /* Special hack: user can direct multicasts |
2340 | and limited broadcast via necessary interface | |
2341 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2342 | This hack is not just for fun, it allows | |
2343 | vic,vat and friends to work. | |
2344 | They bind socket to loopback, set ttl to zero | |
2345 | and expect that it will work. | |
2346 | From the viewpoint of routing cache they are broken, | |
2347 | because we are not allowed to build multicast path | |
2348 | with loopback source addr (look, routing cache | |
2349 | cannot know, that ttl is zero, so that packet | |
2350 | will not leave this host and route is valid). | |
2351 | Luckily, this hack is good workaround. | |
2352 | */ | |
2353 | ||
813b3b5d | 2354 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2355 | goto make_route; |
2356 | } | |
a210d01a | 2357 | |
813b3b5d | 2358 | if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) { |
a210d01a | 2359 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ |
813b3b5d | 2360 | if (!__ip_dev_find(net, fl4->saddr, false)) |
a210d01a | 2361 | goto out; |
a210d01a | 2362 | } |
1da177e4 LT |
2363 | } |
2364 | ||
2365 | ||
813b3b5d DM |
2366 | if (fl4->flowi4_oif) { |
2367 | dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif); | |
b23dd4fe | 2368 | rth = ERR_PTR(-ENODEV); |
51456b29 | 2369 | if (!dev_out) |
1da177e4 | 2370 | goto out; |
e5ed6399 HX |
2371 | |
2372 | /* RACE: Check return value of inet_select_addr instead. */ | |
fc75fc83 | 2373 | if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) { |
b23dd4fe | 2374 | rth = ERR_PTR(-ENETUNREACH); |
fc75fc83 ED |
2375 | goto out; |
2376 | } | |
813b3b5d | 2377 | if (ipv4_is_local_multicast(fl4->daddr) || |
6a211654 AL |
2378 | ipv4_is_lbcast(fl4->daddr) || |
2379 | fl4->flowi4_proto == IPPROTO_IGMP) { | |
813b3b5d DM |
2380 | if (!fl4->saddr) |
2381 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2382 | RT_SCOPE_LINK); | |
1da177e4 LT |
2383 | goto make_route; |
2384 | } | |
0a7e2260 | 2385 | if (!fl4->saddr) { |
813b3b5d DM |
2386 | if (ipv4_is_multicast(fl4->daddr)) |
2387 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2388 | fl4->flowi4_scope); | |
2389 | else if (!fl4->daddr) | |
2390 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2391 | RT_SCOPE_HOST); | |
1da177e4 LT |
2392 | } |
2393 | } | |
2394 | ||
813b3b5d DM |
2395 | if (!fl4->daddr) { |
2396 | fl4->daddr = fl4->saddr; | |
2397 | if (!fl4->daddr) | |
2398 | fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK); | |
b40afd0e | 2399 | dev_out = net->loopback_dev; |
1fb9489b | 2400 | fl4->flowi4_oif = LOOPBACK_IFINDEX; |
3abd1ade | 2401 | res->type = RTN_LOCAL; |
1da177e4 LT |
2402 | flags |= RTCF_LOCAL; |
2403 | goto make_route; | |
2404 | } | |
2405 | ||
3abd1ade | 2406 | err = fib_lookup(net, fl4, res, 0); |
0315e382 | 2407 | if (err) { |
3abd1ade DA |
2408 | res->fi = NULL; |
2409 | res->table = NULL; | |
6104e112 | 2410 | if (fl4->flowi4_oif && |
e58e4159 DA |
2411 | (ipv4_is_multicast(fl4->daddr) || |
2412 | !netif_index_is_l3_master(net, fl4->flowi4_oif))) { | |
1da177e4 LT |
2413 | /* Apparently, routing tables are wrong. Assume, |
2414 | that the destination is on link. | |
2415 | ||
2416 | WHY? DW. | |
2417 | Because we are allowed to send to iface | |
2418 | even if it has NO routes and NO assigned | |
2419 | addresses. When oif is specified, routing | |
2420 | tables are looked up with only one purpose: | |
2421 | to catch if destination is gatewayed, rather than | |
2422 | direct. Moreover, if MSG_DONTROUTE is set, | |
2423 | we send packet, ignoring both routing tables | |
2424 | and ifaddr state. --ANK | |
2425 | ||
2426 | ||
2427 | We could make it even if oif is unknown, | |
2428 | likely IPv6, but we do not. | |
2429 | */ | |
2430 | ||
813b3b5d DM |
2431 | if (fl4->saddr == 0) |
2432 | fl4->saddr = inet_select_addr(dev_out, 0, | |
2433 | RT_SCOPE_LINK); | |
3abd1ade | 2434 | res->type = RTN_UNICAST; |
1da177e4 LT |
2435 | goto make_route; |
2436 | } | |
0315e382 | 2437 | rth = ERR_PTR(err); |
1da177e4 LT |
2438 | goto out; |
2439 | } | |
1da177e4 | 2440 | |
3abd1ade | 2441 | if (res->type == RTN_LOCAL) { |
813b3b5d | 2442 | if (!fl4->saddr) { |
3abd1ade DA |
2443 | if (res->fi->fib_prefsrc) |
2444 | fl4->saddr = res->fi->fib_prefsrc; | |
9fc3bbb4 | 2445 | else |
813b3b5d | 2446 | fl4->saddr = fl4->daddr; |
9fc3bbb4 | 2447 | } |
5f02ce24 DA |
2448 | |
2449 | /* L3 master device is the loopback for that domain */ | |
3abd1ade | 2450 | dev_out = l3mdev_master_dev_rcu(FIB_RES_DEV(*res)) ? : |
b7c8487c | 2451 | net->loopback_dev; |
839da4d9 DA |
2452 | |
2453 | /* make sure orig_oif points to fib result device even | |
2454 | * though packet rx/tx happens over loopback or l3mdev | |
2455 | */ | |
2456 | orig_oif = FIB_RES_OIF(*res); | |
2457 | ||
813b3b5d | 2458 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2459 | flags |= RTCF_LOCAL; |
2460 | goto make_route; | |
2461 | } | |
2462 | ||
3abd1ade | 2463 | fib_select_path(net, res, fl4, skb); |
1da177e4 | 2464 | |
3abd1ade | 2465 | dev_out = FIB_RES_DEV(*res); |
813b3b5d | 2466 | fl4->flowi4_oif = dev_out->ifindex; |
1da177e4 LT |
2467 | |
2468 | ||
2469 | make_route: | |
3abd1ade | 2470 | rth = __mkroute_output(res, fl4, orig_oif, dev_out, flags); |
1da177e4 | 2471 | |
010c2708 | 2472 | out: |
b23dd4fe | 2473 | return rth; |
1da177e4 | 2474 | } |
d8c97a94 | 2475 | |
ae2688d5 JW |
2476 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) |
2477 | { | |
2478 | return NULL; | |
2479 | } | |
2480 | ||
ebb762f2 | 2481 | static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst) |
ec831ea7 | 2482 | { |
618f9bc7 SK |
2483 | unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); |
2484 | ||
2485 | return mtu ? : dst->dev->mtu; | |
ec831ea7 RD |
2486 | } |
2487 | ||
6700c270 DM |
2488 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk, |
2489 | struct sk_buff *skb, u32 mtu) | |
14e50e57 DM |
2490 | { |
2491 | } | |
2492 | ||
6700c270 DM |
2493 | static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk, |
2494 | struct sk_buff *skb) | |
b587ee3b DM |
2495 | { |
2496 | } | |
2497 | ||
0972ddb2 HB |
2498 | static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst, |
2499 | unsigned long old) | |
2500 | { | |
2501 | return NULL; | |
2502 | } | |
2503 | ||
14e50e57 DM |
2504 | static struct dst_ops ipv4_dst_blackhole_ops = { |
2505 | .family = AF_INET, | |
ae2688d5 | 2506 | .check = ipv4_blackhole_dst_check, |
ebb762f2 | 2507 | .mtu = ipv4_blackhole_mtu, |
214f45c9 | 2508 | .default_advmss = ipv4_default_advmss, |
14e50e57 | 2509 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, |
b587ee3b | 2510 | .redirect = ipv4_rt_blackhole_redirect, |
0972ddb2 | 2511 | .cow_metrics = ipv4_rt_blackhole_cow_metrics, |
d3aaeb38 | 2512 | .neigh_lookup = ipv4_neigh_lookup, |
14e50e57 DM |
2513 | }; |
2514 | ||
2774c131 | 2515 | struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig) |
14e50e57 | 2516 | { |
2774c131 | 2517 | struct rtable *ort = (struct rtable *) dst_orig; |
f5b0a874 | 2518 | struct rtable *rt; |
14e50e57 | 2519 | |
6c0e7284 | 2520 | rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_DEAD, 0); |
14e50e57 | 2521 | if (rt) { |
d8d1f30b | 2522 | struct dst_entry *new = &rt->dst; |
14e50e57 | 2523 | |
14e50e57 | 2524 | new->__use = 1; |
352e512c | 2525 | new->input = dst_discard; |
ede2059d | 2526 | new->output = dst_discard_out; |
14e50e57 | 2527 | |
1dbe3252 | 2528 | new->dev = net->loopback_dev; |
14e50e57 DM |
2529 | if (new->dev) |
2530 | dev_hold(new->dev); | |
2531 | ||
9917e1e8 | 2532 | rt->rt_is_input = ort->rt_is_input; |
5e2b61f7 | 2533 | rt->rt_iif = ort->rt_iif; |
5943634f | 2534 | rt->rt_pmtu = ort->rt_pmtu; |
14e50e57 | 2535 | |
ca4c3fc2 | 2536 | rt->rt_genid = rt_genid_ipv4(net); |
14e50e57 DM |
2537 | rt->rt_flags = ort->rt_flags; |
2538 | rt->rt_type = ort->rt_type; | |
14e50e57 | 2539 | rt->rt_gateway = ort->rt_gateway; |
155e8336 | 2540 | rt->rt_uses_gateway = ort->rt_uses_gateway; |
14e50e57 | 2541 | |
caacf05e | 2542 | INIT_LIST_HEAD(&rt->rt_uncached); |
14e50e57 DM |
2543 | } |
2544 | ||
2774c131 DM |
2545 | dst_release(dst_orig); |
2546 | ||
2547 | return rt ? &rt->dst : ERR_PTR(-ENOMEM); | |
14e50e57 DM |
2548 | } |
2549 | ||
9d6ec938 | 2550 | struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4, |
6f9c9615 | 2551 | const struct sock *sk) |
1da177e4 | 2552 | { |
9d6ec938 | 2553 | struct rtable *rt = __ip_route_output_key(net, flp4); |
1da177e4 | 2554 | |
b23dd4fe DM |
2555 | if (IS_ERR(rt)) |
2556 | return rt; | |
1da177e4 | 2557 | |
56157872 | 2558 | if (flp4->flowi4_proto) |
f92ee619 SK |
2559 | rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst, |
2560 | flowi4_to_flowi(flp4), | |
2561 | sk, 0); | |
1da177e4 | 2562 | |
b23dd4fe | 2563 | return rt; |
1da177e4 | 2564 | } |
d8c97a94 ACM |
2565 | EXPORT_SYMBOL_GPL(ip_route_output_flow); |
2566 | ||
3765d35e | 2567 | /* called with rcu_read_lock held */ |
c36ba660 | 2568 | static int rt_fill_info(struct net *net, __be32 dst, __be32 src, u32 table_id, |
15e47304 | 2569 | struct flowi4 *fl4, struct sk_buff *skb, u32 portid, |
ba52d61e | 2570 | u32 seq) |
1da177e4 | 2571 | { |
ba52d61e | 2572 | struct rtable *rt = skb_rtable(skb); |
1da177e4 | 2573 | struct rtmsg *r; |
be403ea1 | 2574 | struct nlmsghdr *nlh; |
2bc8ca40 | 2575 | unsigned long expires = 0; |
f185071d | 2576 | u32 error; |
521f5490 | 2577 | u32 metrics[RTAX_MAX]; |
be403ea1 | 2578 | |
d3166e0c | 2579 | nlh = nlmsg_put(skb, portid, seq, RTM_NEWROUTE, sizeof(*r), 0); |
51456b29 | 2580 | if (!nlh) |
26932566 | 2581 | return -EMSGSIZE; |
be403ea1 TG |
2582 | |
2583 | r = nlmsg_data(nlh); | |
1da177e4 LT |
2584 | r->rtm_family = AF_INET; |
2585 | r->rtm_dst_len = 32; | |
2586 | r->rtm_src_len = 0; | |
d6c0a4f6 | 2587 | r->rtm_tos = fl4->flowi4_tos; |
8a430ed5 | 2588 | r->rtm_table = table_id < 256 ? table_id : RT_TABLE_COMPAT; |
c36ba660 | 2589 | if (nla_put_u32(skb, RTA_TABLE, table_id)) |
f3756b79 | 2590 | goto nla_put_failure; |
1da177e4 LT |
2591 | r->rtm_type = rt->rt_type; |
2592 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2593 | r->rtm_protocol = RTPROT_UNSPEC; | |
2594 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2595 | if (rt->rt_flags & RTCF_NOTIFY) | |
2596 | r->rtm_flags |= RTM_F_NOTIFY; | |
df4d9254 HFS |
2597 | if (IPCB(skb)->flags & IPSKB_DOREDIRECT) |
2598 | r->rtm_flags |= RTCF_DOREDIRECT; | |
be403ea1 | 2599 | |
930345ea | 2600 | if (nla_put_in_addr(skb, RTA_DST, dst)) |
f3756b79 | 2601 | goto nla_put_failure; |
1a00fee4 | 2602 | if (src) { |
1da177e4 | 2603 | r->rtm_src_len = 32; |
930345ea | 2604 | if (nla_put_in_addr(skb, RTA_SRC, src)) |
f3756b79 | 2605 | goto nla_put_failure; |
1da177e4 | 2606 | } |
f3756b79 DM |
2607 | if (rt->dst.dev && |
2608 | nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) | |
2609 | goto nla_put_failure; | |
c7066f70 | 2610 | #ifdef CONFIG_IP_ROUTE_CLASSID |
f3756b79 DM |
2611 | if (rt->dst.tclassid && |
2612 | nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid)) | |
2613 | goto nla_put_failure; | |
1da177e4 | 2614 | #endif |
41347dcd | 2615 | if (!rt_is_input_route(rt) && |
d6c0a4f6 | 2616 | fl4->saddr != src) { |
930345ea | 2617 | if (nla_put_in_addr(skb, RTA_PREFSRC, fl4->saddr)) |
f3756b79 DM |
2618 | goto nla_put_failure; |
2619 | } | |
155e8336 | 2620 | if (rt->rt_uses_gateway && |
930345ea | 2621 | nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gateway)) |
f3756b79 | 2622 | goto nla_put_failure; |
be403ea1 | 2623 | |
ee9a8f7a SK |
2624 | expires = rt->dst.expires; |
2625 | if (expires) { | |
2626 | unsigned long now = jiffies; | |
2627 | ||
2628 | if (time_before(now, expires)) | |
2629 | expires -= now; | |
2630 | else | |
2631 | expires = 0; | |
2632 | } | |
2633 | ||
521f5490 | 2634 | memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics)); |
ee9a8f7a | 2635 | if (rt->rt_pmtu && expires) |
521f5490 JA |
2636 | metrics[RTAX_MTU - 1] = rt->rt_pmtu; |
2637 | if (rtnetlink_put_metrics(skb, metrics) < 0) | |
be403ea1 TG |
2638 | goto nla_put_failure; |
2639 | ||
b4869889 | 2640 | if (fl4->flowi4_mark && |
68aaed54 | 2641 | nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark)) |
f3756b79 | 2642 | goto nla_put_failure; |
963bfeee | 2643 | |
622ec2c9 LC |
2644 | if (!uid_eq(fl4->flowi4_uid, INVALID_UID) && |
2645 | nla_put_u32(skb, RTA_UID, | |
2646 | from_kuid_munged(current_user_ns(), fl4->flowi4_uid))) | |
2647 | goto nla_put_failure; | |
2648 | ||
d8d1f30b | 2649 | error = rt->dst.error; |
be403ea1 | 2650 | |
c7537967 | 2651 | if (rt_is_input_route(rt)) { |
8caaf7b6 ND |
2652 | #ifdef CONFIG_IP_MROUTE |
2653 | if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) && | |
2654 | IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { | |
2655 | int err = ipmr_get_route(net, skb, | |
2656 | fl4->saddr, fl4->daddr, | |
9f09eaea | 2657 | r, portid); |
2cf75070 | 2658 | |
8caaf7b6 | 2659 | if (err <= 0) { |
0c8d803f DA |
2660 | if (err == 0) |
2661 | return 0; | |
2662 | goto nla_put_failure; | |
8caaf7b6 ND |
2663 | } |
2664 | } else | |
2665 | #endif | |
91146153 | 2666 | if (nla_put_u32(skb, RTA_IIF, skb->dev->ifindex)) |
8caaf7b6 | 2667 | goto nla_put_failure; |
1da177e4 LT |
2668 | } |
2669 | ||
f185071d | 2670 | if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0) |
e3703b3d | 2671 | goto nla_put_failure; |
be403ea1 | 2672 | |
053c095a JB |
2673 | nlmsg_end(skb, nlh); |
2674 | return 0; | |
1da177e4 | 2675 | |
be403ea1 | 2676 | nla_put_failure: |
26932566 PM |
2677 | nlmsg_cancel(skb, nlh); |
2678 | return -EMSGSIZE; | |
1da177e4 LT |
2679 | } |
2680 | ||
c21ef3e3 DA |
2681 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, |
2682 | struct netlink_ext_ack *extack) | |
1da177e4 | 2683 | { |
3b1e0a65 | 2684 | struct net *net = sock_net(in_skb->sk); |
d889ce3b TG |
2685 | struct rtmsg *rtm; |
2686 | struct nlattr *tb[RTA_MAX+1]; | |
3765d35e | 2687 | struct fib_result res = {}; |
1da177e4 | 2688 | struct rtable *rt = NULL; |
d6c0a4f6 | 2689 | struct flowi4 fl4; |
9e12bb22 AV |
2690 | __be32 dst = 0; |
2691 | __be32 src = 0; | |
2692 | u32 iif; | |
d889ce3b | 2693 | int err; |
963bfeee | 2694 | int mark; |
1da177e4 | 2695 | struct sk_buff *skb; |
c36ba660 | 2696 | u32 table_id = RT_TABLE_MAIN; |
622ec2c9 | 2697 | kuid_t uid; |
1da177e4 | 2698 | |
fceb6435 | 2699 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy, |
c21ef3e3 | 2700 | extack); |
d889ce3b TG |
2701 | if (err < 0) |
2702 | goto errout; | |
2703 | ||
2704 | rtm = nlmsg_data(nlh); | |
2705 | ||
1da177e4 | 2706 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
51456b29 | 2707 | if (!skb) { |
d889ce3b TG |
2708 | err = -ENOBUFS; |
2709 | goto errout; | |
2710 | } | |
1da177e4 LT |
2711 | |
2712 | /* Reserve room for dummy headers, this skb can pass | |
2713 | through good chunk of routing engine. | |
2714 | */ | |
459a98ed | 2715 | skb_reset_mac_header(skb); |
c1d2bbe1 | 2716 | skb_reset_network_header(skb); |
d2c962b8 | 2717 | |
67b61f6c JB |
2718 | src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0; |
2719 | dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0; | |
d889ce3b | 2720 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; |
963bfeee | 2721 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; |
622ec2c9 LC |
2722 | if (tb[RTA_UID]) |
2723 | uid = make_kuid(current_user_ns(), nla_get_u32(tb[RTA_UID])); | |
2724 | else | |
2725 | uid = (iif ? INVALID_UID : current_uid()); | |
1da177e4 | 2726 | |
bbadb9a2 FL |
2727 | /* Bugfix: need to give ip_route_input enough of an IP header to |
2728 | * not gag. | |
2729 | */ | |
2730 | ip_hdr(skb)->protocol = IPPROTO_UDP; | |
2731 | ip_hdr(skb)->saddr = src; | |
2732 | ip_hdr(skb)->daddr = dst; | |
2733 | ||
2734 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); | |
2735 | ||
d6c0a4f6 DM |
2736 | memset(&fl4, 0, sizeof(fl4)); |
2737 | fl4.daddr = dst; | |
2738 | fl4.saddr = src; | |
2739 | fl4.flowi4_tos = rtm->rtm_tos; | |
2740 | fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0; | |
2741 | fl4.flowi4_mark = mark; | |
622ec2c9 | 2742 | fl4.flowi4_uid = uid; |
d6c0a4f6 | 2743 | |
3765d35e DA |
2744 | rcu_read_lock(); |
2745 | ||
1da177e4 | 2746 | if (iif) { |
d889ce3b TG |
2747 | struct net_device *dev; |
2748 | ||
3765d35e | 2749 | dev = dev_get_by_index_rcu(net, iif); |
51456b29 | 2750 | if (!dev) { |
d889ce3b TG |
2751 | err = -ENODEV; |
2752 | goto errout_free; | |
2753 | } | |
2754 | ||
1da177e4 LT |
2755 | skb->protocol = htons(ETH_P_IP); |
2756 | skb->dev = dev; | |
963bfeee | 2757 | skb->mark = mark; |
3765d35e DA |
2758 | err = ip_route_input_rcu(skb, dst, src, rtm->rtm_tos, |
2759 | dev, &res); | |
d889ce3b | 2760 | |
511c3f92 | 2761 | rt = skb_rtable(skb); |
d8d1f30b CG |
2762 | if (err == 0 && rt->dst.error) |
2763 | err = -rt->dst.error; | |
1da177e4 | 2764 | } else { |
3765d35e | 2765 | rt = ip_route_output_key_hash_rcu(net, &fl4, &res, skb); |
b23dd4fe DM |
2766 | err = 0; |
2767 | if (IS_ERR(rt)) | |
2768 | err = PTR_ERR(rt); | |
2c87d63a FW |
2769 | else |
2770 | skb_dst_set(skb, &rt->dst); | |
1da177e4 | 2771 | } |
d889ce3b | 2772 | |
1da177e4 | 2773 | if (err) |
d889ce3b | 2774 | goto errout_free; |
1da177e4 | 2775 | |
1da177e4 LT |
2776 | if (rtm->rtm_flags & RTM_F_NOTIFY) |
2777 | rt->rt_flags |= RTCF_NOTIFY; | |
2778 | ||
c36ba660 DA |
2779 | if (rtm->rtm_flags & RTM_F_LOOKUP_TABLE) |
2780 | table_id = rt->rt_table_id; | |
2781 | ||
bc3aae2b RP |
2782 | if (rtm->rtm_flags & RTM_F_FIB_MATCH) { |
2783 | if (!res.fi) { | |
2784 | err = fib_props[res.type].error; | |
2785 | if (!err) | |
2786 | err = -EHOSTUNREACH; | |
2787 | goto errout_free; | |
2788 | } | |
b6179813 RP |
2789 | err = fib_dump_info(skb, NETLINK_CB(in_skb).portid, |
2790 | nlh->nlmsg_seq, RTM_NEWROUTE, table_id, | |
2791 | rt->rt_type, res.prefix, res.prefixlen, | |
2792 | fl4.flowi4_tos, res.fi, 0); | |
bc3aae2b | 2793 | } else { |
b6179813 | 2794 | err = rt_fill_info(net, dst, src, table_id, &fl4, skb, |
ba52d61e | 2795 | NETLINK_CB(in_skb).portid, nlh->nlmsg_seq); |
bc3aae2b | 2796 | } |
7b46a644 | 2797 | if (err < 0) |
d889ce3b | 2798 | goto errout_free; |
1da177e4 | 2799 | |
3765d35e DA |
2800 | rcu_read_unlock(); |
2801 | ||
15e47304 | 2802 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); |
d889ce3b | 2803 | errout: |
2942e900 | 2804 | return err; |
1da177e4 | 2805 | |
d889ce3b | 2806 | errout_free: |
3765d35e | 2807 | rcu_read_unlock(); |
1da177e4 | 2808 | kfree_skb(skb); |
d889ce3b | 2809 | goto errout; |
1da177e4 LT |
2810 | } |
2811 | ||
1da177e4 LT |
2812 | void ip_rt_multicast_event(struct in_device *in_dev) |
2813 | { | |
4ccfe6d4 | 2814 | rt_cache_flush(dev_net(in_dev->dev)); |
1da177e4 LT |
2815 | } |
2816 | ||
2817 | #ifdef CONFIG_SYSCTL | |
082c7ca4 G |
2818 | static int ip_rt_gc_interval __read_mostly = 60 * HZ; |
2819 | static int ip_rt_gc_min_interval __read_mostly = HZ / 2; | |
2820 | static int ip_rt_gc_elasticity __read_mostly = 8; | |
2821 | ||
fe2c6338 | 2822 | static int ipv4_sysctl_rtcache_flush(struct ctl_table *__ctl, int write, |
8d65af78 | 2823 | void __user *buffer, |
1da177e4 LT |
2824 | size_t *lenp, loff_t *ppos) |
2825 | { | |
5aad1de5 TT |
2826 | struct net *net = (struct net *)__ctl->extra1; |
2827 | ||
1da177e4 | 2828 | if (write) { |
5aad1de5 TT |
2829 | rt_cache_flush(net); |
2830 | fnhe_genid_bump(net); | |
1da177e4 | 2831 | return 0; |
e905a9ed | 2832 | } |
1da177e4 LT |
2833 | |
2834 | return -EINVAL; | |
2835 | } | |
2836 | ||
fe2c6338 | 2837 | static struct ctl_table ipv4_route_table[] = { |
1da177e4 | 2838 | { |
1da177e4 LT |
2839 | .procname = "gc_thresh", |
2840 | .data = &ipv4_dst_ops.gc_thresh, | |
2841 | .maxlen = sizeof(int), | |
2842 | .mode = 0644, | |
6d9f239a | 2843 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2844 | }, |
2845 | { | |
1da177e4 LT |
2846 | .procname = "max_size", |
2847 | .data = &ip_rt_max_size, | |
2848 | .maxlen = sizeof(int), | |
2849 | .mode = 0644, | |
6d9f239a | 2850 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2851 | }, |
2852 | { | |
2853 | /* Deprecated. Use gc_min_interval_ms */ | |
e905a9ed | 2854 | |
1da177e4 LT |
2855 | .procname = "gc_min_interval", |
2856 | .data = &ip_rt_gc_min_interval, | |
2857 | .maxlen = sizeof(int), | |
2858 | .mode = 0644, | |
6d9f239a | 2859 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
2860 | }, |
2861 | { | |
1da177e4 LT |
2862 | .procname = "gc_min_interval_ms", |
2863 | .data = &ip_rt_gc_min_interval, | |
2864 | .maxlen = sizeof(int), | |
2865 | .mode = 0644, | |
6d9f239a | 2866 | .proc_handler = proc_dointvec_ms_jiffies, |
1da177e4 LT |
2867 | }, |
2868 | { | |
1da177e4 LT |
2869 | .procname = "gc_timeout", |
2870 | .data = &ip_rt_gc_timeout, | |
2871 | .maxlen = sizeof(int), | |
2872 | .mode = 0644, | |
6d9f239a | 2873 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 | 2874 | }, |
9f28a2fc ED |
2875 | { |
2876 | .procname = "gc_interval", | |
2877 | .data = &ip_rt_gc_interval, | |
2878 | .maxlen = sizeof(int), | |
2879 | .mode = 0644, | |
2880 | .proc_handler = proc_dointvec_jiffies, | |
2881 | }, | |
1da177e4 | 2882 | { |
1da177e4 LT |
2883 | .procname = "redirect_load", |
2884 | .data = &ip_rt_redirect_load, | |
2885 | .maxlen = sizeof(int), | |
2886 | .mode = 0644, | |
6d9f239a | 2887 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2888 | }, |
2889 | { | |
1da177e4 LT |
2890 | .procname = "redirect_number", |
2891 | .data = &ip_rt_redirect_number, | |
2892 | .maxlen = sizeof(int), | |
2893 | .mode = 0644, | |
6d9f239a | 2894 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2895 | }, |
2896 | { | |
1da177e4 LT |
2897 | .procname = "redirect_silence", |
2898 | .data = &ip_rt_redirect_silence, | |
2899 | .maxlen = sizeof(int), | |
2900 | .mode = 0644, | |
6d9f239a | 2901 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2902 | }, |
2903 | { | |
1da177e4 LT |
2904 | .procname = "error_cost", |
2905 | .data = &ip_rt_error_cost, | |
2906 | .maxlen = sizeof(int), | |
2907 | .mode = 0644, | |
6d9f239a | 2908 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2909 | }, |
2910 | { | |
1da177e4 LT |
2911 | .procname = "error_burst", |
2912 | .data = &ip_rt_error_burst, | |
2913 | .maxlen = sizeof(int), | |
2914 | .mode = 0644, | |
6d9f239a | 2915 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2916 | }, |
2917 | { | |
1da177e4 LT |
2918 | .procname = "gc_elasticity", |
2919 | .data = &ip_rt_gc_elasticity, | |
2920 | .maxlen = sizeof(int), | |
2921 | .mode = 0644, | |
6d9f239a | 2922 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2923 | }, |
2924 | { | |
1da177e4 LT |
2925 | .procname = "mtu_expires", |
2926 | .data = &ip_rt_mtu_expires, | |
2927 | .maxlen = sizeof(int), | |
2928 | .mode = 0644, | |
6d9f239a | 2929 | .proc_handler = proc_dointvec_jiffies, |
1da177e4 LT |
2930 | }, |
2931 | { | |
1da177e4 LT |
2932 | .procname = "min_pmtu", |
2933 | .data = &ip_rt_min_pmtu, | |
2934 | .maxlen = sizeof(int), | |
2935 | .mode = 0644, | |
6d9f239a | 2936 | .proc_handler = proc_dointvec, |
1da177e4 LT |
2937 | }, |
2938 | { | |
1da177e4 LT |
2939 | .procname = "min_adv_mss", |
2940 | .data = &ip_rt_min_advmss, | |
2941 | .maxlen = sizeof(int), | |
2942 | .mode = 0644, | |
6d9f239a | 2943 | .proc_handler = proc_dointvec, |
1da177e4 | 2944 | }, |
f8572d8f | 2945 | { } |
1da177e4 | 2946 | }; |
39a23e75 | 2947 | |
39a23e75 DL |
2948 | static struct ctl_table ipv4_route_flush_table[] = { |
2949 | { | |
39a23e75 DL |
2950 | .procname = "flush", |
2951 | .maxlen = sizeof(int), | |
2952 | .mode = 0200, | |
6d9f239a | 2953 | .proc_handler = ipv4_sysctl_rtcache_flush, |
39a23e75 | 2954 | }, |
f8572d8f | 2955 | { }, |
39a23e75 DL |
2956 | }; |
2957 | ||
2958 | static __net_init int sysctl_route_net_init(struct net *net) | |
2959 | { | |
2960 | struct ctl_table *tbl; | |
2961 | ||
2962 | tbl = ipv4_route_flush_table; | |
09ad9bc7 | 2963 | if (!net_eq(net, &init_net)) { |
39a23e75 | 2964 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); |
51456b29 | 2965 | if (!tbl) |
39a23e75 | 2966 | goto err_dup; |
464dc801 EB |
2967 | |
2968 | /* Don't export sysctls to unprivileged users */ | |
2969 | if (net->user_ns != &init_user_ns) | |
2970 | tbl[0].procname = NULL; | |
39a23e75 DL |
2971 | } |
2972 | tbl[0].extra1 = net; | |
2973 | ||
ec8f23ce | 2974 | net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl); |
51456b29 | 2975 | if (!net->ipv4.route_hdr) |
39a23e75 DL |
2976 | goto err_reg; |
2977 | return 0; | |
2978 | ||
2979 | err_reg: | |
2980 | if (tbl != ipv4_route_flush_table) | |
2981 | kfree(tbl); | |
2982 | err_dup: | |
2983 | return -ENOMEM; | |
2984 | } | |
2985 | ||
2986 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
2987 | { | |
2988 | struct ctl_table *tbl; | |
2989 | ||
2990 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
2991 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
2992 | BUG_ON(tbl == ipv4_route_flush_table); | |
2993 | kfree(tbl); | |
2994 | } | |
2995 | ||
2996 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
2997 | .init = sysctl_route_net_init, | |
2998 | .exit = sysctl_route_net_exit, | |
2999 | }; | |
1da177e4 LT |
3000 | #endif |
3001 | ||
3ee94372 | 3002 | static __net_init int rt_genid_init(struct net *net) |
9f5e97e5 | 3003 | { |
ca4c3fc2 | 3004 | atomic_set(&net->ipv4.rt_genid, 0); |
5aad1de5 | 3005 | atomic_set(&net->fnhe_genid, 0); |
7aed9f72 | 3006 | atomic_set(&net->ipv4.dev_addr_genid, get_random_int()); |
9f5e97e5 DL |
3007 | return 0; |
3008 | } | |
3009 | ||
3ee94372 NH |
3010 | static __net_initdata struct pernet_operations rt_genid_ops = { |
3011 | .init = rt_genid_init, | |
9f5e97e5 DL |
3012 | }; |
3013 | ||
c3426b47 DM |
3014 | static int __net_init ipv4_inetpeer_init(struct net *net) |
3015 | { | |
3016 | struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL); | |
3017 | ||
3018 | if (!bp) | |
3019 | return -ENOMEM; | |
3020 | inet_peer_base_init(bp); | |
3021 | net->ipv4.peers = bp; | |
3022 | return 0; | |
3023 | } | |
3024 | ||
3025 | static void __net_exit ipv4_inetpeer_exit(struct net *net) | |
3026 | { | |
3027 | struct inet_peer_base *bp = net->ipv4.peers; | |
3028 | ||
3029 | net->ipv4.peers = NULL; | |
56a6b248 | 3030 | inetpeer_invalidate_tree(bp); |
c3426b47 DM |
3031 | kfree(bp); |
3032 | } | |
3033 | ||
3034 | static __net_initdata struct pernet_operations ipv4_inetpeer_ops = { | |
3035 | .init = ipv4_inetpeer_init, | |
3036 | .exit = ipv4_inetpeer_exit, | |
3037 | }; | |
9f5e97e5 | 3038 | |
c7066f70 | 3039 | #ifdef CONFIG_IP_ROUTE_CLASSID |
7d720c3e | 3040 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; |
c7066f70 | 3041 | #endif /* CONFIG_IP_ROUTE_CLASSID */ |
1da177e4 | 3042 | |
1da177e4 LT |
3043 | int __init ip_rt_init(void) |
3044 | { | |
5055c371 | 3045 | int cpu; |
1da177e4 | 3046 | |
73f156a6 ED |
3047 | ip_idents = kmalloc(IP_IDENTS_SZ * sizeof(*ip_idents), GFP_KERNEL); |
3048 | if (!ip_idents) | |
3049 | panic("IP: failed to allocate ip_idents\n"); | |
3050 | ||
3051 | prandom_bytes(ip_idents, IP_IDENTS_SZ * sizeof(*ip_idents)); | |
3052 | ||
355b590c ED |
3053 | ip_tstamps = kcalloc(IP_IDENTS_SZ, sizeof(*ip_tstamps), GFP_KERNEL); |
3054 | if (!ip_tstamps) | |
3055 | panic("IP: failed to allocate ip_tstamps\n"); | |
3056 | ||
5055c371 ED |
3057 | for_each_possible_cpu(cpu) { |
3058 | struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu); | |
3059 | ||
3060 | INIT_LIST_HEAD(&ul->head); | |
3061 | spin_lock_init(&ul->lock); | |
3062 | } | |
c7066f70 | 3063 | #ifdef CONFIG_IP_ROUTE_CLASSID |
0dcec8c2 | 3064 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); |
1da177e4 LT |
3065 | if (!ip_rt_acct) |
3066 | panic("IP: failed to allocate ip_rt_acct\n"); | |
1da177e4 LT |
3067 | #endif |
3068 | ||
e5d679f3 AD |
3069 | ipv4_dst_ops.kmem_cachep = |
3070 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
20c2df83 | 3071 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); |
1da177e4 | 3072 | |
14e50e57 DM |
3073 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; |
3074 | ||
fc66f95c ED |
3075 | if (dst_entries_init(&ipv4_dst_ops) < 0) |
3076 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
3077 | ||
3078 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
3079 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
3080 | ||
89aef892 DM |
3081 | ipv4_dst_ops.gc_thresh = ~0; |
3082 | ip_rt_max_size = INT_MAX; | |
1da177e4 | 3083 | |
1da177e4 LT |
3084 | devinet_init(); |
3085 | ip_fib_init(); | |
3086 | ||
73b38711 | 3087 | if (ip_rt_proc_init()) |
058bd4d2 | 3088 | pr_err("Unable to create route proc files\n"); |
1da177e4 LT |
3089 | #ifdef CONFIG_XFRM |
3090 | xfrm_init(); | |
703fb94e | 3091 | xfrm4_init(); |
1da177e4 | 3092 | #endif |
394f51ab FW |
3093 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, |
3094 | RTNL_FLAG_DOIT_UNLOCKED); | |
63f3444f | 3095 | |
39a23e75 DL |
3096 | #ifdef CONFIG_SYSCTL |
3097 | register_pernet_subsys(&sysctl_route_ops); | |
3098 | #endif | |
3ee94372 | 3099 | register_pernet_subsys(&rt_genid_ops); |
c3426b47 | 3100 | register_pernet_subsys(&ipv4_inetpeer_ops); |
1bcdca3f | 3101 | return 0; |
1da177e4 LT |
3102 | } |
3103 | ||
a1bc6eb4 | 3104 | #ifdef CONFIG_SYSCTL |
eeb61f71 AV |
3105 | /* |
3106 | * We really need to sanitize the damn ipv4 init order, then all | |
3107 | * this nonsense will go away. | |
3108 | */ | |
3109 | void __init ip_static_sysctl_init(void) | |
3110 | { | |
4e5ca785 | 3111 | register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table); |
eeb61f71 | 3112 | } |
a1bc6eb4 | 3113 | #endif |