blob: 02c62299d717b9f6c38a5227e3b3ae376e0015b6 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 *
Jesper Juhl02c30a82005-05-05 16:16:16 -07008 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * 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
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090021 * Alan Cox : Super /proc >4K
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 * 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.
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090039 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 * 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
Eric Dumazetbb1d23b2005-07-05 15:00:32 -070055 * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes.
Ilia Sotnikovcef26852006-03-25 01:38:55 -080056 * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect
57 * Ilia Sotnikov : Removed TOS from hash calculations
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 *
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
Joe Perchesafd465032012-03-12 07:03:32 +000065#define pr_fmt(fmt) "IPv4: " fmt
66
Linus Torvalds1da177e2005-04-16 15:20:36 -070067#include <linux/module.h>
68#include <asm/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070069#include <linux/bitops.h>
70#include <linux/types.h>
71#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070072#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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070083#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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070089#include <linux/rcupdate.h>
90#include <linux/times.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090091#include <linux/slab.h>
Eric Dumazet73f156a2014-06-02 05:26:03 -070092#include <linux/jhash.h>
Herbert Xu352e5122007-11-13 21:34:06 -080093#include <net/dst.h>
Thomas Graf1b7179d2015-07-21 10:43:59 +020094#include <net/dst_metadata.h>
Eric W. Biederman457c4cb2007-09-12 12:01:34 +020095#include <net/net_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070096#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>
Roopa Prabhu571e7222015-07-21 10:43:47 +0200106#include <net/lwtunnel.h>
Tom Tucker8d717402006-07-30 20:43:36 -0700107#include <net/netevent.h>
Thomas Graf63f34442007-03-22 11:55:17 -0700108#include <net/rtnetlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109#ifdef CONFIG_SYSCTL
110#include <linux/sysctl.h>
Shan Wei7426a562012-04-18 18:05:46 +0000111#include <linux/kmemleak.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112#endif
David S. Miller6e5714e2011-08-03 20:50:44 -0700113#include <net/secure_seq.h>
Thomas Graf1b7179d2015-07-21 10:43:59 +0200114#include <net/ip_tunnels.h>
David Ahern385add92015-09-29 20:07:13 -0700115#include <net/l3mdev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116
David S. Miller68a5e3d2011-03-11 20:07:33 -0500117#define RT_FL_TOS(oldflp4) \
Julian Anastasovf61759e2011-12-02 11:39:42 +0000118 ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120#define RT_GC_TIMEOUT (300*HZ)
121
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122static int ip_rt_max_size;
Stephen Hemminger817bc4d2008-03-22 17:43:59 -0700123static int ip_rt_redirect_number __read_mostly = 9;
124static int ip_rt_redirect_load __read_mostly = HZ / 50;
125static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
126static int ip_rt_error_cost __read_mostly = HZ;
127static int ip_rt_error_burst __read_mostly = 5 * HZ;
Stephen Hemminger817bc4d2008-03-22 17:43:59 -0700128static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
129static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
130static int ip_rt_min_advmss __read_mostly = 256;
Eric Dumazet9f28a2f2011-12-21 15:47:16 -0500131
Xin Longdeed49d2016-02-18 21:21:19 +0800132static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133/*
134 * Interface to generic destination cache.
135 */
136
137static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
David S. Miller0dbaee32010-12-13 12:52:14 -0800138static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
Steffen Klassertebb762f2011-11-23 02:12:51 +0000139static unsigned int ipv4_mtu(const struct dst_entry *dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
141static void ipv4_link_failure(struct sk_buff *skb);
David S. Miller6700c272012-07-17 03:29:28 -0700142static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
143 struct sk_buff *skb, u32 mtu);
144static void ip_do_redirect(struct dst_entry *dst, struct sock *sk,
145 struct sk_buff *skb);
David S. Millercaacf052012-07-31 15:06:50 -0700146static void ipv4_dst_destroy(struct dst_entry *dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147
David S. Miller62fa8a82011-01-26 20:51:05 -0800148static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
149{
David S. Miller31248732012-07-10 07:08:18 -0700150 WARN_ON(1);
151 return NULL;
David S. Miller62fa8a82011-01-26 20:51:05 -0800152}
153
David S. Millerf894cbf2012-07-02 21:52:24 -0700154static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
155 struct sk_buff *skb,
156 const void *daddr);
David S. Millerd3aaeb32011-07-18 00:40:17 -0700157
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158static struct dst_ops ipv4_dst_ops = {
159 .family = AF_INET,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 .check = ipv4_dst_check,
David S. Miller0dbaee32010-12-13 12:52:14 -0800161 .default_advmss = ipv4_default_advmss,
Steffen Klassertebb762f2011-11-23 02:12:51 +0000162 .mtu = ipv4_mtu,
David S. Miller62fa8a82011-01-26 20:51:05 -0800163 .cow_metrics = ipv4_cow_metrics,
David S. Millercaacf052012-07-31 15:06:50 -0700164 .destroy = ipv4_dst_destroy,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 .negative_advice = ipv4_negative_advice,
166 .link_failure = ipv4_link_failure,
167 .update_pmtu = ip_rt_update_pmtu,
David S. Millere47a1852012-07-11 20:55:47 -0700168 .redirect = ip_do_redirect,
Eric W. Biedermanb92dacd2015-10-07 16:48:37 -0500169 .local_out = __ip_local_out,
David S. Millerd3aaeb32011-07-18 00:40:17 -0700170 .neigh_lookup = ipv4_neigh_lookup,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171};
172
173#define ECN_OR_COST(class) TC_PRIO_##class
174
Philippe De Muyter4839c522007-07-09 15:32:57 -0700175const __u8 ip_tos2prio[16] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 TC_PRIO_BESTEFFORT,
Dan Siemon4a2b9c32011-03-15 13:56:07 +0000177 ECN_OR_COST(BESTEFFORT),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 TC_PRIO_BESTEFFORT,
179 ECN_OR_COST(BESTEFFORT),
180 TC_PRIO_BULK,
181 ECN_OR_COST(BULK),
182 TC_PRIO_BULK,
183 ECN_OR_COST(BULK),
184 TC_PRIO_INTERACTIVE,
185 ECN_OR_COST(INTERACTIVE),
186 TC_PRIO_INTERACTIVE,
187 ECN_OR_COST(INTERACTIVE),
188 TC_PRIO_INTERACTIVE_BULK,
189 ECN_OR_COST(INTERACTIVE_BULK),
190 TC_PRIO_INTERACTIVE_BULK,
191 ECN_OR_COST(INTERACTIVE_BULK)
192};
Amir Vadaid4a96862012-04-04 21:33:28 +0000193EXPORT_SYMBOL(ip_tos2prio);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194
Eric Dumazet2f970d82006-01-17 02:54:36 -0800195static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
Christoph Lameter3ed66e92014-04-07 15:39:40 -0700196#define RT_CACHE_STAT_INC(field) raw_cpu_inc(rt_cache_stat.field)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198#ifdef CONFIG_PROC_FS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
200{
Eric Dumazet29e75252008-01-31 17:05:09 -0800201 if (*pos)
David S. Miller89aef892012-07-17 11:00:09 -0700202 return NULL;
Eric Dumazet29e75252008-01-31 17:05:09 -0800203 return SEQ_START_TOKEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204}
205
206static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
207{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 ++*pos;
David S. Miller89aef892012-07-17 11:00:09 -0700209 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210}
211
212static void rt_cache_seq_stop(struct seq_file *seq, void *v)
213{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214}
215
216static int rt_cache_seq_show(struct seq_file *seq, void *v)
217{
218 if (v == SEQ_START_TOKEN)
219 seq_printf(seq, "%-127s\n",
220 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
221 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
222 "HHUptod\tSpecDst");
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900223 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224}
225
Stephen Hemmingerf6908082007-03-12 14:34:29 -0700226static const struct seq_operations rt_cache_seq_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 .start = rt_cache_seq_start,
228 .next = rt_cache_seq_next,
229 .stop = rt_cache_seq_stop,
230 .show = rt_cache_seq_show,
231};
232
233static int rt_cache_seq_open(struct inode *inode, struct file *file)
234{
David S. Miller89aef892012-07-17 11:00:09 -0700235 return seq_open(file, &rt_cache_seq_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236}
237
Arjan van de Ven9a321442007-02-12 00:55:35 -0800238static const struct file_operations rt_cache_seq_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 .owner = THIS_MODULE,
240 .open = rt_cache_seq_open,
241 .read = seq_read,
242 .llseek = seq_lseek,
David S. Miller89aef892012-07-17 11:00:09 -0700243 .release = seq_release,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244};
245
246
247static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
248{
249 int cpu;
250
251 if (*pos == 0)
252 return SEQ_START_TOKEN;
253
Rusty Russell0f23174a2008-12-29 12:23:42 +0000254 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 if (!cpu_possible(cpu))
256 continue;
257 *pos = cpu+1;
Eric Dumazet2f970d82006-01-17 02:54:36 -0800258 return &per_cpu(rt_cache_stat, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 }
260 return NULL;
261}
262
263static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
264{
265 int cpu;
266
Rusty Russell0f23174a2008-12-29 12:23:42 +0000267 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 if (!cpu_possible(cpu))
269 continue;
270 *pos = cpu+1;
Eric Dumazet2f970d82006-01-17 02:54:36 -0800271 return &per_cpu(rt_cache_stat, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 }
273 return NULL;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900274
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275}
276
277static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
278{
279
280}
281
282static int rt_cpu_seq_show(struct seq_file *seq, void *v)
283{
284 struct rt_cache_stat *st = v;
285
286 if (v == SEQ_START_TOKEN) {
Olaf Rempel5bec0032005-04-28 12:16:08 -0700287 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");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 return 0;
289 }
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900290
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
292 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
Eric Dumazetfc66f952010-10-08 06:37:34 +0000293 dst_entries_get_slow(&ipv4_dst_ops),
Eric Dumazet0baf2b32013-10-16 02:49:04 -0700294 0, /* st->in_hit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 st->in_slow_tot,
296 st->in_slow_mc,
297 st->in_no_route,
298 st->in_brd,
299 st->in_martian_dst,
300 st->in_martian_src,
301
Eric Dumazet0baf2b32013-10-16 02:49:04 -0700302 0, /* st->out_hit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 st->out_slow_tot,
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900304 st->out_slow_mc,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
Eric Dumazet0baf2b32013-10-16 02:49:04 -0700306 0, /* st->gc_total */
307 0, /* st->gc_ignored */
308 0, /* st->gc_goal_miss */
309 0, /* st->gc_dst_overflow */
310 0, /* st->in_hlist_search */
311 0 /* st->out_hlist_search */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 );
313 return 0;
314}
315
Stephen Hemmingerf6908082007-03-12 14:34:29 -0700316static const struct seq_operations rt_cpu_seq_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 .start = rt_cpu_seq_start,
318 .next = rt_cpu_seq_next,
319 .stop = rt_cpu_seq_stop,
320 .show = rt_cpu_seq_show,
321};
322
323
324static int rt_cpu_seq_open(struct inode *inode, struct file *file)
325{
326 return seq_open(file, &rt_cpu_seq_ops);
327}
328
Arjan van de Ven9a321442007-02-12 00:55:35 -0800329static const struct file_operations rt_cpu_seq_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 .owner = THIS_MODULE,
331 .open = rt_cpu_seq_open,
332 .read = seq_read,
333 .llseek = seq_lseek,
334 .release = seq_release,
335};
336
Patrick McHardyc7066f72011-01-14 13:36:42 +0100337#ifdef CONFIG_IP_ROUTE_CLASSID
Alexey Dobriyana661c412009-11-25 15:40:35 -0800338static int rt_acct_proc_show(struct seq_file *m, void *v)
Pavel Emelyanov78c686e2007-12-05 21:13:48 -0800339{
Alexey Dobriyana661c412009-11-25 15:40:35 -0800340 struct ip_rt_acct *dst, *src;
341 unsigned int i, j;
Pavel Emelyanov78c686e2007-12-05 21:13:48 -0800342
Alexey Dobriyana661c412009-11-25 15:40:35 -0800343 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
344 if (!dst)
345 return -ENOMEM;
Pavel Emelyanov78c686e2007-12-05 21:13:48 -0800346
Alexey Dobriyana661c412009-11-25 15:40:35 -0800347 for_each_possible_cpu(i) {
348 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
349 for (j = 0; j < 256; j++) {
350 dst[j].o_bytes += src[j].o_bytes;
351 dst[j].o_packets += src[j].o_packets;
352 dst[j].i_bytes += src[j].i_bytes;
353 dst[j].i_packets += src[j].i_packets;
Pavel Emelyanov78c686e2007-12-05 21:13:48 -0800354 }
355 }
Alexey Dobriyana661c412009-11-25 15:40:35 -0800356
357 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
358 kfree(dst);
359 return 0;
Pavel Emelyanov78c686e2007-12-05 21:13:48 -0800360}
Alexey Dobriyana661c412009-11-25 15:40:35 -0800361
362static int rt_acct_proc_open(struct inode *inode, struct file *file)
363{
364 return single_open(file, rt_acct_proc_show, NULL);
365}
366
367static const struct file_operations rt_acct_proc_fops = {
368 .owner = THIS_MODULE,
369 .open = rt_acct_proc_open,
370 .read = seq_read,
371 .llseek = seq_lseek,
372 .release = single_release,
373};
Pavel Emelyanov78c686e2007-12-05 21:13:48 -0800374#endif
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800375
Denis V. Lunev73b38712008-02-28 20:51:18 -0800376static int __net_init ip_rt_do_proc_init(struct net *net)
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800377{
378 struct proc_dir_entry *pde;
379
Gao fengd4beaa62013-02-18 01:34:54 +0000380 pde = proc_create("rt_cache", S_IRUGO, net->proc_net,
381 &rt_cache_seq_fops);
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800382 if (!pde)
383 goto err1;
384
Wang Chen77020722008-02-28 14:14:25 -0800385 pde = proc_create("rt_cache", S_IRUGO,
386 net->proc_net_stat, &rt_cpu_seq_fops);
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800387 if (!pde)
388 goto err2;
389
Patrick McHardyc7066f72011-01-14 13:36:42 +0100390#ifdef CONFIG_IP_ROUTE_CLASSID
Alexey Dobriyana661c412009-11-25 15:40:35 -0800391 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800392 if (!pde)
393 goto err3;
394#endif
395 return 0;
396
Patrick McHardyc7066f72011-01-14 13:36:42 +0100397#ifdef CONFIG_IP_ROUTE_CLASSID
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800398err3:
399 remove_proc_entry("rt_cache", net->proc_net_stat);
400#endif
401err2:
402 remove_proc_entry("rt_cache", net->proc_net);
403err1:
404 return -ENOMEM;
405}
Denis V. Lunev73b38712008-02-28 20:51:18 -0800406
407static void __net_exit ip_rt_do_proc_exit(struct net *net)
408{
409 remove_proc_entry("rt_cache", net->proc_net_stat);
410 remove_proc_entry("rt_cache", net->proc_net);
Patrick McHardyc7066f72011-01-14 13:36:42 +0100411#ifdef CONFIG_IP_ROUTE_CLASSID
Denis V. Lunev73b38712008-02-28 20:51:18 -0800412 remove_proc_entry("rt_acct", net->proc_net);
Alexey Dobriyan0a931ac2010-01-17 03:32:50 +0000413#endif
Denis V. Lunev73b38712008-02-28 20:51:18 -0800414}
415
416static struct pernet_operations ip_rt_proc_ops __net_initdata = {
417 .init = ip_rt_do_proc_init,
418 .exit = ip_rt_do_proc_exit,
419};
420
421static int __init ip_rt_proc_init(void)
422{
423 return register_pernet_subsys(&ip_rt_proc_ops);
424}
425
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800426#else
Denis V. Lunev73b38712008-02-28 20:51:18 -0800427static inline int ip_rt_proc_init(void)
Pavel Emelyanov107f1632007-12-05 21:14:28 -0800428{
429 return 0;
430}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431#endif /* CONFIG_PROC_FS */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900432
Eric Dumazet4331deb2012-07-25 05:11:23 +0000433static inline bool rt_is_expired(const struct rtable *rth)
Denis V. Luneve84f84f2008-07-05 19:04:32 -0700434{
fan.duca4c3fc2013-07-30 08:33:53 +0800435 return rth->rt_genid != rt_genid_ipv4(dev_net(rth->dst.dev));
Denis V. Luneve84f84f2008-07-05 19:04:32 -0700436}
437
Nicolas Dichtel4ccfe6d2012-09-07 00:45:29 +0000438void rt_cache_flush(struct net *net)
Eric Dumazet29e75252008-01-31 17:05:09 -0800439{
fan.duca4c3fc2013-07-30 08:33:53 +0800440 rt_genid_bump_ipv4(net);
Eric Dumazet98376382010-03-08 03:20:00 +0000441}
442
David S. Millerf894cbf2012-07-02 21:52:24 -0700443static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
444 struct sk_buff *skb,
445 const void *daddr)
David Miller3769cff2011-07-11 22:44:24 +0000446{
David S. Millerd3aaeb32011-07-18 00:40:17 -0700447 struct net_device *dev = dst->dev;
448 const __be32 *pkey = daddr;
David S. Miller39232972012-01-26 15:22:32 -0500449 const struct rtable *rt;
David Miller3769cff2011-07-11 22:44:24 +0000450 struct neighbour *n;
451
David S. Miller39232972012-01-26 15:22:32 -0500452 rt = (const struct rtable *) dst;
David S. Millera263b302012-07-02 02:02:15 -0700453 if (rt->rt_gateway)
David S. Miller39232972012-01-26 15:22:32 -0500454 pkey = (const __be32 *) &rt->rt_gateway;
David S. Millerf894cbf2012-07-02 21:52:24 -0700455 else if (skb)
456 pkey = &ip_hdr(skb)->daddr;
David S. Millerd3aaeb32011-07-18 00:40:17 -0700457
David S. Miller80703d22012-02-15 17:48:35 -0500458 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
David S. Millerd3aaeb32011-07-18 00:40:17 -0700459 if (n)
460 return n;
David Miller32092ec2011-07-25 00:01:41 +0000461 return neigh_create(&arp_tbl, pkey, dev);
David S. Millerd3aaeb32011-07-18 00:40:17 -0700462}
463
Eric Dumazet04ca6972014-07-26 08:58:10 +0200464#define IP_IDENTS_SZ 2048u
Eric Dumazet04ca6972014-07-26 08:58:10 +0200465
Eric Dumazet355b5902015-05-01 10:37:49 -0700466static atomic_t *ip_idents __read_mostly;
467static u32 *ip_tstamps __read_mostly;
Eric Dumazet04ca6972014-07-26 08:58:10 +0200468
469/* In order to protect privacy, we add a perturbation to identifiers
470 * if one generator is seldom used. This makes hard for an attacker
471 * to infer how many packets were sent between two points in time.
472 */
473u32 ip_idents_reserve(u32 hash, int segs)
474{
Eric Dumazet355b5902015-05-01 10:37:49 -0700475 u32 *p_tstamp = ip_tstamps + hash % IP_IDENTS_SZ;
476 atomic_t *p_id = ip_idents + hash % IP_IDENTS_SZ;
477 u32 old = ACCESS_ONCE(*p_tstamp);
Eric Dumazet04ca6972014-07-26 08:58:10 +0200478 u32 now = (u32)jiffies;
479 u32 delta = 0;
480
Eric Dumazet355b5902015-05-01 10:37:49 -0700481 if (old != now && cmpxchg(p_tstamp, old, now) == old)
Eric Dumazet04ca6972014-07-26 08:58:10 +0200482 delta = prandom_u32_max(now - old);
483
Eric Dumazet355b5902015-05-01 10:37:49 -0700484 return atomic_add_return(segs + delta, p_id) - segs;
Eric Dumazet04ca6972014-07-26 08:58:10 +0200485}
486EXPORT_SYMBOL(ip_idents_reserve);
Eric Dumazet73f156a2014-06-02 05:26:03 -0700487
Hannes Frederic Sowab6a77192015-03-25 17:07:44 +0100488void __ip_select_ident(struct net *net, struct iphdr *iph, int segs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489{
Eric Dumazet73f156a2014-06-02 05:26:03 -0700490 static u32 ip_idents_hashrnd __read_mostly;
491 u32 hash, id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492
Eric Dumazet73f156a2014-06-02 05:26:03 -0700493 net_get_random_once(&ip_idents_hashrnd, sizeof(ip_idents_hashrnd));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
Eric Dumazet04ca6972014-07-26 08:58:10 +0200495 hash = jhash_3words((__force u32)iph->daddr,
496 (__force u32)iph->saddr,
Hannes Frederic Sowab6a77192015-03-25 17:07:44 +0100497 iph->protocol ^ net_hash_mix(net),
Eric Dumazet04ca6972014-07-26 08:58:10 +0200498 ip_idents_hashrnd);
Eric Dumazet73f156a2014-06-02 05:26:03 -0700499 id = ip_idents_reserve(hash, segs);
500 iph->id = htons(id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501}
Eric Dumazet4bc2f182010-07-09 21:22:10 +0000502EXPORT_SYMBOL(__ip_select_ident);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503
Eric Dumazet5abf7f72012-07-17 22:42:13 +0200504static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk,
David S. Miller4895c772012-07-17 04:19:00 -0700505 const struct iphdr *iph,
506 int oif, u8 tos,
507 u8 prot, u32 mark, int flow_flags)
508{
509 if (sk) {
510 const struct inet_sock *inet = inet_sk(sk);
511
512 oif = sk->sk_bound_dev_if;
513 mark = sk->sk_mark;
514 tos = RT_CONN_FLAGS(sk);
515 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
516 }
517 flowi4_init_output(fl4, oif, mark, tos,
518 RT_SCOPE_UNIVERSE, prot,
519 flow_flags,
520 iph->daddr, iph->saddr, 0, 0);
521}
522
Eric Dumazet5abf7f72012-07-17 22:42:13 +0200523static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
524 const struct sock *sk)
David S. Miller4895c772012-07-17 04:19:00 -0700525{
526 const struct iphdr *iph = ip_hdr(skb);
527 int oif = skb->dev->ifindex;
528 u8 tos = RT_TOS(iph->tos);
529 u8 prot = iph->protocol;
530 u32 mark = skb->mark;
531
532 __build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0);
533}
534
Eric Dumazet5abf7f72012-07-17 22:42:13 +0200535static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
David S. Miller4895c772012-07-17 04:19:00 -0700536{
537 const struct inet_sock *inet = inet_sk(sk);
Eric Dumazet5abf7f72012-07-17 22:42:13 +0200538 const struct ip_options_rcu *inet_opt;
David S. Miller4895c772012-07-17 04:19:00 -0700539 __be32 daddr = inet->inet_daddr;
540
541 rcu_read_lock();
542 inet_opt = rcu_dereference(inet->inet_opt);
543 if (inet_opt && inet_opt->opt.srr)
544 daddr = inet_opt->opt.faddr;
545 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
546 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
547 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
548 inet_sk_flowi_flags(sk),
549 daddr, inet->inet_saddr, 0, 0);
550 rcu_read_unlock();
551}
552
Eric Dumazet5abf7f72012-07-17 22:42:13 +0200553static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
554 const struct sk_buff *skb)
David S. Miller4895c772012-07-17 04:19:00 -0700555{
556 if (skb)
557 build_skb_flow_key(fl4, skb, sk);
558 else
559 build_sk_flow_key(fl4, sk);
560}
561
David S. Millerc5038a82012-07-31 15:02:02 -0700562static inline void rt_free(struct rtable *rt)
563{
564 call_rcu(&rt->dst.rcu_head, dst_rcu_free);
565}
566
567static DEFINE_SPINLOCK(fnhe_lock);
David S. Miller4895c772012-07-17 04:19:00 -0700568
Timo Teräs2ffae992013-06-27 10:27:05 +0300569static void fnhe_flush_routes(struct fib_nh_exception *fnhe)
570{
571 struct rtable *rt;
572
573 rt = rcu_dereference(fnhe->fnhe_rth_input);
574 if (rt) {
575 RCU_INIT_POINTER(fnhe->fnhe_rth_input, NULL);
576 rt_free(rt);
577 }
578 rt = rcu_dereference(fnhe->fnhe_rth_output);
579 if (rt) {
580 RCU_INIT_POINTER(fnhe->fnhe_rth_output, NULL);
581 rt_free(rt);
582 }
583}
584
Julian Anastasovaee06da2012-07-18 10:15:35 +0000585static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
David S. Miller4895c772012-07-17 04:19:00 -0700586{
587 struct fib_nh_exception *fnhe, *oldest;
588
589 oldest = rcu_dereference(hash->chain);
590 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
591 fnhe = rcu_dereference(fnhe->fnhe_next)) {
592 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
593 oldest = fnhe;
594 }
Timo Teräs2ffae992013-06-27 10:27:05 +0300595 fnhe_flush_routes(oldest);
David S. Miller4895c772012-07-17 04:19:00 -0700596 return oldest;
597}
598
David S. Millerd3a25c92012-07-17 13:23:08 -0700599static inline u32 fnhe_hashfun(__be32 daddr)
600{
Eric Dumazetd546c622014-09-04 08:21:31 -0700601 static u32 fnhe_hashrnd __read_mostly;
David S. Millerd3a25c92012-07-17 13:23:08 -0700602 u32 hval;
603
Eric Dumazetd546c622014-09-04 08:21:31 -0700604 net_get_random_once(&fnhe_hashrnd, sizeof(fnhe_hashrnd));
605 hval = jhash_1word((__force u32) daddr, fnhe_hashrnd);
606 return hash_32(hval, FNHE_HASH_SHIFT);
David S. Millerd3a25c92012-07-17 13:23:08 -0700607}
608
Timo Teräs387aa652013-05-27 20:46:31 +0000609static void fill_route_from_fnhe(struct rtable *rt, struct fib_nh_exception *fnhe)
610{
611 rt->rt_pmtu = fnhe->fnhe_pmtu;
612 rt->dst.expires = fnhe->fnhe_expires;
613
614 if (fnhe->fnhe_gw) {
615 rt->rt_flags |= RTCF_REDIRECTED;
616 rt->rt_gateway = fnhe->fnhe_gw;
617 rt->rt_uses_gateway = 1;
618 }
619}
620
Julian Anastasovaee06da2012-07-18 10:15:35 +0000621static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
622 u32 pmtu, unsigned long expires)
David S. Miller4895c772012-07-17 04:19:00 -0700623{
Julian Anastasovaee06da2012-07-18 10:15:35 +0000624 struct fnhe_hash_bucket *hash;
David S. Miller4895c772012-07-17 04:19:00 -0700625 struct fib_nh_exception *fnhe;
Timo Teräs387aa652013-05-27 20:46:31 +0000626 struct rtable *rt;
627 unsigned int i;
David S. Miller4895c772012-07-17 04:19:00 -0700628 int depth;
Julian Anastasovaee06da2012-07-18 10:15:35 +0000629 u32 hval = fnhe_hashfun(daddr);
David S. Miller4895c772012-07-17 04:19:00 -0700630
David S. Millerc5038a82012-07-31 15:02:02 -0700631 spin_lock_bh(&fnhe_lock);
Julian Anastasovaee06da2012-07-18 10:15:35 +0000632
Eric Dumazetcaa41522014-09-03 22:21:56 -0700633 hash = rcu_dereference(nh->nh_exceptions);
David S. Miller4895c772012-07-17 04:19:00 -0700634 if (!hash) {
Julian Anastasovaee06da2012-07-18 10:15:35 +0000635 hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC);
David S. Miller4895c772012-07-17 04:19:00 -0700636 if (!hash)
Julian Anastasovaee06da2012-07-18 10:15:35 +0000637 goto out_unlock;
Eric Dumazetcaa41522014-09-03 22:21:56 -0700638 rcu_assign_pointer(nh->nh_exceptions, hash);
David S. Miller4895c772012-07-17 04:19:00 -0700639 }
640
David S. Miller4895c772012-07-17 04:19:00 -0700641 hash += hval;
642
643 depth = 0;
644 for (fnhe = rcu_dereference(hash->chain); fnhe;
645 fnhe = rcu_dereference(fnhe->fnhe_next)) {
646 if (fnhe->fnhe_daddr == daddr)
Julian Anastasovaee06da2012-07-18 10:15:35 +0000647 break;
David S. Miller4895c772012-07-17 04:19:00 -0700648 depth++;
649 }
650
Julian Anastasovaee06da2012-07-18 10:15:35 +0000651 if (fnhe) {
652 if (gw)
653 fnhe->fnhe_gw = gw;
654 if (pmtu) {
655 fnhe->fnhe_pmtu = pmtu;
Timo Teräs387aa652013-05-27 20:46:31 +0000656 fnhe->fnhe_expires = max(1UL, expires);
Julian Anastasovaee06da2012-07-18 10:15:35 +0000657 }
Timo Teräs387aa652013-05-27 20:46:31 +0000658 /* Update all cached dsts too */
Timo Teräs2ffae992013-06-27 10:27:05 +0300659 rt = rcu_dereference(fnhe->fnhe_rth_input);
660 if (rt)
661 fill_route_from_fnhe(rt, fnhe);
662 rt = rcu_dereference(fnhe->fnhe_rth_output);
Timo Teräs387aa652013-05-27 20:46:31 +0000663 if (rt)
664 fill_route_from_fnhe(rt, fnhe);
Julian Anastasovaee06da2012-07-18 10:15:35 +0000665 } else {
666 if (depth > FNHE_RECLAIM_DEPTH)
667 fnhe = fnhe_oldest(hash);
668 else {
669 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
670 if (!fnhe)
671 goto out_unlock;
672
673 fnhe->fnhe_next = hash->chain;
674 rcu_assign_pointer(hash->chain, fnhe);
675 }
Timo Teräs5aad1de2013-05-27 20:46:33 +0000676 fnhe->fnhe_genid = fnhe_genid(dev_net(nh->nh_dev));
Julian Anastasovaee06da2012-07-18 10:15:35 +0000677 fnhe->fnhe_daddr = daddr;
678 fnhe->fnhe_gw = gw;
679 fnhe->fnhe_pmtu = pmtu;
680 fnhe->fnhe_expires = expires;
Timo Teräs387aa652013-05-27 20:46:31 +0000681
682 /* Exception created; mark the cached routes for the nexthop
683 * stale, so anyone caching it rechecks if this exception
684 * applies to them.
685 */
Timo Teräs2ffae992013-06-27 10:27:05 +0300686 rt = rcu_dereference(nh->nh_rth_input);
687 if (rt)
688 rt->dst.obsolete = DST_OBSOLETE_KILL;
689
Timo Teräs387aa652013-05-27 20:46:31 +0000690 for_each_possible_cpu(i) {
691 struct rtable __rcu **prt;
692 prt = per_cpu_ptr(nh->nh_pcpu_rth_output, i);
693 rt = rcu_dereference(*prt);
694 if (rt)
695 rt->dst.obsolete = DST_OBSOLETE_KILL;
696 }
David S. Miller4895c772012-07-17 04:19:00 -0700697 }
David S. Miller4895c772012-07-17 04:19:00 -0700698
David S. Miller4895c772012-07-17 04:19:00 -0700699 fnhe->fnhe_stamp = jiffies;
Julian Anastasovaee06da2012-07-18 10:15:35 +0000700
701out_unlock:
David S. Millerc5038a82012-07-31 15:02:02 -0700702 spin_unlock_bh(&fnhe_lock);
David S. Miller4895c772012-07-17 04:19:00 -0700703}
704
David S. Millerceb33202012-07-17 11:31:28 -0700705static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4,
706 bool kill_route)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707{
David S. Millere47a1852012-07-11 20:55:47 -0700708 __be32 new_gw = icmp_hdr(skb)->un.gateway;
David S. Miller94206122012-07-11 20:38:08 -0700709 __be32 old_gw = ip_hdr(skb)->saddr;
David S. Millere47a1852012-07-11 20:55:47 -0700710 struct net_device *dev = skb->dev;
David S. Millere47a1852012-07-11 20:55:47 -0700711 struct in_device *in_dev;
David S. Miller4895c772012-07-17 04:19:00 -0700712 struct fib_result res;
David S. Millere47a1852012-07-11 20:55:47 -0700713 struct neighbour *n;
Denis V. Lunev317805b2008-02-28 20:50:06 -0800714 struct net *net;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715
David S. Miller94206122012-07-11 20:38:08 -0700716 switch (icmp_hdr(skb)->code & 7) {
717 case ICMP_REDIR_NET:
718 case ICMP_REDIR_NETTOS:
719 case ICMP_REDIR_HOST:
720 case ICMP_REDIR_HOSTTOS:
721 break;
722
723 default:
724 return;
725 }
726
David S. Millere47a1852012-07-11 20:55:47 -0700727 if (rt->rt_gateway != old_gw)
728 return;
729
730 in_dev = __in_dev_get_rcu(dev);
731 if (!in_dev)
732 return;
733
YOSHIFUJI Hideakic346dca2008-03-25 21:47:49 +0900734 net = dev_net(dev);
Joe Perches9d4fb272009-11-23 10:41:23 -0800735 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
736 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
737 ipv4_is_zeronet(new_gw))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 goto reject_redirect;
739
740 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
741 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
742 goto reject_redirect;
743 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
744 goto reject_redirect;
745 } else {
Denis V. Lunev317805b2008-02-28 20:50:06 -0800746 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 goto reject_redirect;
748 }
749
David S. Miller4895c772012-07-17 04:19:00 -0700750 n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw);
WANG Cong2c1a4312014-09-24 17:07:53 -0700751 if (!IS_ERR(n)) {
David S. Millere47a1852012-07-11 20:55:47 -0700752 if (!(n->nud_state & NUD_VALID)) {
753 neigh_event_send(n, NULL);
754 } else {
Andy Gospodarek0eeb0752015-06-23 13:45:37 -0400755 if (fib_lookup(net, fl4, &res, 0) == 0) {
David S. Miller4895c772012-07-17 04:19:00 -0700756 struct fib_nh *nh = &FIB_RES_NH(res);
David S. Miller4895c772012-07-17 04:19:00 -0700757
Julian Anastasovaee06da2012-07-18 10:15:35 +0000758 update_or_create_fnhe(nh, fl4->daddr, new_gw,
Xin Longdeed49d2016-02-18 21:21:19 +0800759 0, jiffies + ip_rt_gc_timeout);
David S. Miller4895c772012-07-17 04:19:00 -0700760 }
David S. Millerceb33202012-07-17 11:31:28 -0700761 if (kill_route)
762 rt->dst.obsolete = DST_OBSOLETE_KILL;
David S. Millere47a1852012-07-11 20:55:47 -0700763 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
764 }
765 neigh_release(n);
766 }
767 return;
768
769reject_redirect:
770#ifdef CONFIG_IP_ROUTE_VERBOSE
David S. Miller99ee0382012-07-12 07:40:05 -0700771 if (IN_DEV_LOG_MARTIANS(in_dev)) {
772 const struct iphdr *iph = (const struct iphdr *) skb->data;
773 __be32 daddr = iph->daddr;
774 __be32 saddr = iph->saddr;
775
David S. Millere47a1852012-07-11 20:55:47 -0700776 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
777 " Advised path = %pI4 -> %pI4\n",
778 &old_gw, dev->name, &new_gw,
779 &saddr, &daddr);
David S. Miller99ee0382012-07-12 07:40:05 -0700780 }
David S. Millere47a1852012-07-11 20:55:47 -0700781#endif
782 ;
783}
784
David S. Miller4895c772012-07-17 04:19:00 -0700785static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
786{
787 struct rtable *rt;
788 struct flowi4 fl4;
Michal Kubecekf96ef982013-05-28 08:26:49 +0200789 const struct iphdr *iph = (const struct iphdr *) skb->data;
790 int oif = skb->dev->ifindex;
791 u8 tos = RT_TOS(iph->tos);
792 u8 prot = iph->protocol;
793 u32 mark = skb->mark;
David S. Miller4895c772012-07-17 04:19:00 -0700794
795 rt = (struct rtable *) dst;
796
Michal Kubecekf96ef982013-05-28 08:26:49 +0200797 __build_flow_key(&fl4, sk, iph, oif, tos, prot, mark, 0);
David S. Millerceb33202012-07-17 11:31:28 -0700798 __ip_do_redirect(rt, skb, &fl4, true);
David S. Miller4895c772012-07-17 04:19:00 -0700799}
800
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
802{
Eric Dumazetee6b9672008-03-05 18:30:47 -0800803 struct rtable *rt = (struct rtable *)dst;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804 struct dst_entry *ret = dst;
805
806 if (rt) {
Timo Teräsd11a4dc2010-03-18 23:20:20 +0000807 if (dst->obsolete > 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 ip_rt_put(rt);
809 ret = NULL;
David S. Miller59436342012-07-10 06:58:42 -0700810 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
811 rt->dst.expires) {
David S. Miller89aef892012-07-17 11:00:09 -0700812 ip_rt_put(rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 ret = NULL;
814 }
815 }
816 return ret;
817}
818
819/*
820 * Algorithm:
821 * 1. The first ip_rt_redirect_number redirects are sent
822 * with exponential backoff, then we stop sending them at all,
823 * assuming that the host ignores our redirects.
824 * 2. If we did not see packets requiring redirects
825 * during ip_rt_redirect_silence, we assume that the host
826 * forgot redirected route and start to send redirects again.
827 *
828 * This algorithm is much cheaper and more intelligent than dumb load limiting
829 * in icmp.c.
830 *
831 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
832 * and "frag. need" (breaks PMTU discovery) in icmp.c.
833 */
834
835void ip_rt_send_redirect(struct sk_buff *skb)
836{
Eric Dumazet511c3f92009-06-02 05:14:27 +0000837 struct rtable *rt = skb_rtable(skb);
Eric Dumazet30038fc2009-08-28 23:52:01 -0700838 struct in_device *in_dev;
David S. Miller92d86822011-02-04 15:55:25 -0800839 struct inet_peer *peer;
David S. Miller1d861aa2012-07-10 03:58:16 -0700840 struct net *net;
Eric Dumazet30038fc2009-08-28 23:52:01 -0700841 int log_martians;
David Ahern192132b2015-08-27 16:07:03 -0700842 int vif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843
Eric Dumazet30038fc2009-08-28 23:52:01 -0700844 rcu_read_lock();
Changli Gaod8d1f302010-06-10 23:31:35 -0700845 in_dev = __in_dev_get_rcu(rt->dst.dev);
Eric Dumazet30038fc2009-08-28 23:52:01 -0700846 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
847 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 return;
Eric Dumazet30038fc2009-08-28 23:52:01 -0700849 }
850 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
David Ahern385add92015-09-29 20:07:13 -0700851 vif = l3mdev_master_ifindex_rcu(rt->dst.dev);
Eric Dumazet30038fc2009-08-28 23:52:01 -0700852 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853
David S. Miller1d861aa2012-07-10 03:58:16 -0700854 net = dev_net(rt->dst.dev);
David Ahern192132b2015-08-27 16:07:03 -0700855 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, vif, 1);
David S. Miller92d86822011-02-04 15:55:25 -0800856 if (!peer) {
Julian Anastasove81da0e2012-10-08 11:41:15 +0000857 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST,
858 rt_nexthop(rt, ip_hdr(skb)->daddr));
David S. Miller92d86822011-02-04 15:55:25 -0800859 return;
860 }
861
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 /* No redirected packets during ip_rt_redirect_silence;
863 * reset the algorithm.
864 */
David S. Miller92d86822011-02-04 15:55:25 -0800865 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
866 peer->rate_tokens = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867
868 /* Too many ignored redirects; do not send anything
Changli Gaod8d1f302010-06-10 23:31:35 -0700869 * set dst.rate_last to the last seen redirected packet.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 */
David S. Miller92d86822011-02-04 15:55:25 -0800871 if (peer->rate_tokens >= ip_rt_redirect_number) {
872 peer->rate_last = jiffies;
David S. Miller1d861aa2012-07-10 03:58:16 -0700873 goto out_put_peer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 }
875
876 /* Check for load limit; set rate_last to the latest sent
877 * redirect.
878 */
David S. Miller92d86822011-02-04 15:55:25 -0800879 if (peer->rate_tokens == 0 ||
Li Yewang14fb8a72006-12-18 00:26:35 -0800880 time_after(jiffies,
David S. Miller92d86822011-02-04 15:55:25 -0800881 (peer->rate_last +
882 (ip_rt_redirect_load << peer->rate_tokens)))) {
Julian Anastasove81da0e2012-10-08 11:41:15 +0000883 __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr);
884
885 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw);
David S. Miller92d86822011-02-04 15:55:25 -0800886 peer->rate_last = jiffies;
887 ++peer->rate_tokens;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888#ifdef CONFIG_IP_ROUTE_VERBOSE
Eric Dumazet30038fc2009-08-28 23:52:01 -0700889 if (log_martians &&
Joe Perchese87cc472012-05-13 21:56:26 +0000890 peer->rate_tokens == ip_rt_redirect_number)
891 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
David S. Miller92101b32012-07-23 16:29:00 -0700892 &ip_hdr(skb)->saddr, inet_iif(skb),
Julian Anastasove81da0e2012-10-08 11:41:15 +0000893 &ip_hdr(skb)->daddr, &gw);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894#endif
895 }
David S. Miller1d861aa2012-07-10 03:58:16 -0700896out_put_peer:
897 inet_putpeer(peer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898}
899
900static int ip_error(struct sk_buff *skb)
901{
David S. Miller251da412012-06-26 16:27:09 -0700902 struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
Eric Dumazet511c3f92009-06-02 05:14:27 +0000903 struct rtable *rt = skb_rtable(skb);
David S. Miller92d86822011-02-04 15:55:25 -0800904 struct inet_peer *peer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 unsigned long now;
David S. Miller251da412012-06-26 16:27:09 -0700906 struct net *net;
David S. Miller92d86822011-02-04 15:55:25 -0800907 bool send;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 int code;
909
Eric W. Biederman381c7592015-05-22 04:58:12 -0500910 /* IP on this device is disabled. */
911 if (!in_dev)
912 goto out;
913
David S. Miller251da412012-06-26 16:27:09 -0700914 net = dev_net(rt->dst.dev);
915 if (!IN_DEV_FORWARD(in_dev)) {
916 switch (rt->dst.error) {
917 case EHOSTUNREACH:
918 IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS);
919 break;
920
921 case ENETUNREACH:
922 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
923 break;
924 }
925 goto out;
926 }
927
Changli Gaod8d1f302010-06-10 23:31:35 -0700928 switch (rt->dst.error) {
Joe Perches4500ebf2011-07-01 09:43:07 +0000929 case EINVAL:
930 default:
931 goto out;
932 case EHOSTUNREACH:
933 code = ICMP_HOST_UNREACH;
934 break;
935 case ENETUNREACH:
936 code = ICMP_NET_UNREACH;
David S. Miller251da412012-06-26 16:27:09 -0700937 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
Joe Perches4500ebf2011-07-01 09:43:07 +0000938 break;
939 case EACCES:
940 code = ICMP_PKT_FILTERED;
941 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 }
943
David Ahern192132b2015-08-27 16:07:03 -0700944 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr,
David Ahern385add92015-09-29 20:07:13 -0700945 l3mdev_master_ifindex(skb->dev), 1);
David S. Miller92d86822011-02-04 15:55:25 -0800946
947 send = true;
948 if (peer) {
949 now = jiffies;
950 peer->rate_tokens += now - peer->rate_last;
951 if (peer->rate_tokens > ip_rt_error_burst)
952 peer->rate_tokens = ip_rt_error_burst;
953 peer->rate_last = now;
954 if (peer->rate_tokens >= ip_rt_error_cost)
955 peer->rate_tokens -= ip_rt_error_cost;
956 else
957 send = false;
David S. Miller1d861aa2012-07-10 03:58:16 -0700958 inet_putpeer(peer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959 }
David S. Miller92d86822011-02-04 15:55:25 -0800960 if (send)
961 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962
963out: kfree_skb(skb);
964 return 0;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900965}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966
Steffen Klassertd851c122012-10-07 22:47:25 +0000967static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968{
Steffen Klassertd851c122012-10-07 22:47:25 +0000969 struct dst_entry *dst = &rt->dst;
David S. Miller4895c772012-07-17 04:19:00 -0700970 struct fib_result res;
David S. Miller2c8cec52011-02-09 20:42:07 -0800971
Steffen Klassertfa1e4922013-01-16 20:58:10 +0000972 if (dst_metric_locked(dst, RTAX_MTU))
973 return;
974
Herbert Xucb6ccf02015-04-28 11:43:15 +0800975 if (ipv4_mtu(dst) < mtu)
Li Wei3cdaa5b2015-01-29 16:09:03 +0800976 return;
977
David S. Miller59436342012-07-10 06:58:42 -0700978 if (mtu < ip_rt_min_pmtu)
979 mtu = ip_rt_min_pmtu;
Eric Dumazetfe6fe792011-06-08 06:07:07 +0000980
Timo Teräsf0162292013-05-27 20:46:32 +0000981 if (rt->rt_pmtu == mtu &&
982 time_before(jiffies, dst->expires - ip_rt_mtu_expires / 2))
983 return;
984
Eric Dumazetc5ae7d42012-08-28 12:33:07 +0000985 rcu_read_lock();
Andy Gospodarek0eeb0752015-06-23 13:45:37 -0400986 if (fib_lookup(dev_net(dst->dev), fl4, &res, 0) == 0) {
David S. Miller4895c772012-07-17 04:19:00 -0700987 struct fib_nh *nh = &FIB_RES_NH(res);
David S. Miller4895c772012-07-17 04:19:00 -0700988
Julian Anastasovaee06da2012-07-18 10:15:35 +0000989 update_or_create_fnhe(nh, fl4->daddr, 0, mtu,
990 jiffies + ip_rt_mtu_expires);
David S. Miller4895c772012-07-17 04:19:00 -0700991 }
Eric Dumazetc5ae7d42012-08-28 12:33:07 +0000992 rcu_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993}
994
David S. Miller4895c772012-07-17 04:19:00 -0700995static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
996 struct sk_buff *skb, u32 mtu)
997{
998 struct rtable *rt = (struct rtable *) dst;
999 struct flowi4 fl4;
1000
1001 ip_rt_build_flow_key(&fl4, sk, skb);
Steffen Klassertd851c122012-10-07 22:47:25 +00001002 __ip_rt_update_pmtu(rt, &fl4, mtu);
David S. Miller4895c772012-07-17 04:19:00 -07001003}
1004
David S. Miller36393392012-06-14 22:21:46 -07001005void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
1006 int oif, u32 mark, u8 protocol, int flow_flags)
1007{
David S. Miller4895c772012-07-17 04:19:00 -07001008 const struct iphdr *iph = (const struct iphdr *) skb->data;
David S. Miller36393392012-06-14 22:21:46 -07001009 struct flowi4 fl4;
1010 struct rtable *rt;
1011
Lorenzo Colitti1b3c61d2014-05-13 10:17:34 -07001012 if (!mark)
1013 mark = IP4_REPLY_MARK(net, skb->mark);
1014
David S. Miller4895c772012-07-17 04:19:00 -07001015 __build_flow_key(&fl4, NULL, iph, oif,
1016 RT_TOS(iph->tos), protocol, mark, flow_flags);
David S. Miller36393392012-06-14 22:21:46 -07001017 rt = __ip_route_output_key(net, &fl4);
1018 if (!IS_ERR(rt)) {
David S. Miller4895c772012-07-17 04:19:00 -07001019 __ip_rt_update_pmtu(rt, &fl4, mtu);
David S. Miller36393392012-06-14 22:21:46 -07001020 ip_rt_put(rt);
1021 }
1022}
1023EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
1024
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001025static void __ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
David S. Miller36393392012-06-14 22:21:46 -07001026{
David S. Miller4895c772012-07-17 04:19:00 -07001027 const struct iphdr *iph = (const struct iphdr *) skb->data;
1028 struct flowi4 fl4;
1029 struct rtable *rt;
David S. Miller36393392012-06-14 22:21:46 -07001030
David S. Miller4895c772012-07-17 04:19:00 -07001031 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
Lorenzo Colitti1b3c61d2014-05-13 10:17:34 -07001032
1033 if (!fl4.flowi4_mark)
1034 fl4.flowi4_mark = IP4_REPLY_MARK(sock_net(sk), skb->mark);
1035
David S. Miller4895c772012-07-17 04:19:00 -07001036 rt = __ip_route_output_key(sock_net(sk), &fl4);
1037 if (!IS_ERR(rt)) {
1038 __ip_rt_update_pmtu(rt, &fl4, mtu);
1039 ip_rt_put(rt);
1040 }
David S. Miller36393392012-06-14 22:21:46 -07001041}
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001042
1043void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
1044{
1045 const struct iphdr *iph = (const struct iphdr *) skb->data;
1046 struct flowi4 fl4;
1047 struct rtable *rt;
Eric Dumazet7f502362014-06-30 01:26:23 -07001048 struct dst_entry *odst = NULL;
Steffen Klassertb44108d2013-01-22 00:01:28 +00001049 bool new = false;
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001050
1051 bh_lock_sock(sk);
Hannes Frederic Sowa482fc602013-11-05 02:24:17 +01001052
1053 if (!ip_sk_accept_pmtu(sk))
1054 goto out;
1055
Eric Dumazet7f502362014-06-30 01:26:23 -07001056 odst = sk_dst_get(sk);
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001057
Eric Dumazet7f502362014-06-30 01:26:23 -07001058 if (sock_owned_by_user(sk) || !odst) {
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001059 __ipv4_sk_update_pmtu(skb, sk, mtu);
1060 goto out;
1061 }
1062
1063 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
1064
Eric Dumazet7f502362014-06-30 01:26:23 -07001065 rt = (struct rtable *)odst;
Ian Morris51456b22015-04-03 09:17:26 +01001066 if (odst->obsolete && !odst->ops->check(odst, 0)) {
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001067 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
1068 if (IS_ERR(rt))
1069 goto out;
Steffen Klassertb44108d2013-01-22 00:01:28 +00001070
1071 new = true;
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001072 }
1073
1074 __ip_rt_update_pmtu((struct rtable *) rt->dst.path, &fl4, mtu);
1075
Eric Dumazet7f502362014-06-30 01:26:23 -07001076 if (!dst_check(&rt->dst, 0)) {
Steffen Klassertb44108d2013-01-22 00:01:28 +00001077 if (new)
1078 dst_release(&rt->dst);
1079
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001080 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
1081 if (IS_ERR(rt))
1082 goto out;
1083
Steffen Klassertb44108d2013-01-22 00:01:28 +00001084 new = true;
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001085 }
1086
Steffen Klassertb44108d2013-01-22 00:01:28 +00001087 if (new)
Eric Dumazet7f502362014-06-30 01:26:23 -07001088 sk_dst_set(sk, &rt->dst);
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001089
1090out:
1091 bh_unlock_sock(sk);
Eric Dumazet7f502362014-06-30 01:26:23 -07001092 dst_release(odst);
Steffen Klassert9cb3a502013-01-21 01:59:11 +00001093}
David S. Miller36393392012-06-14 22:21:46 -07001094EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
David S. Millerf39925d2011-02-09 22:00:16 -08001095
David S. Millerb42597e2012-07-11 21:25:45 -07001096void ipv4_redirect(struct sk_buff *skb, struct net *net,
1097 int oif, u32 mark, u8 protocol, int flow_flags)
1098{
David S. Miller4895c772012-07-17 04:19:00 -07001099 const struct iphdr *iph = (const struct iphdr *) skb->data;
David S. Millerb42597e2012-07-11 21:25:45 -07001100 struct flowi4 fl4;
1101 struct rtable *rt;
1102
David S. Miller4895c772012-07-17 04:19:00 -07001103 __build_flow_key(&fl4, NULL, iph, oif,
1104 RT_TOS(iph->tos), protocol, mark, flow_flags);
David S. Millerb42597e2012-07-11 21:25:45 -07001105 rt = __ip_route_output_key(net, &fl4);
1106 if (!IS_ERR(rt)) {
David S. Millerceb33202012-07-17 11:31:28 -07001107 __ip_do_redirect(rt, skb, &fl4, false);
David S. Millerb42597e2012-07-11 21:25:45 -07001108 ip_rt_put(rt);
1109 }
1110}
1111EXPORT_SYMBOL_GPL(ipv4_redirect);
1112
1113void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
1114{
David S. Miller4895c772012-07-17 04:19:00 -07001115 const struct iphdr *iph = (const struct iphdr *) skb->data;
1116 struct flowi4 fl4;
1117 struct rtable *rt;
David S. Millerb42597e2012-07-11 21:25:45 -07001118
David S. Miller4895c772012-07-17 04:19:00 -07001119 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
1120 rt = __ip_route_output_key(sock_net(sk), &fl4);
1121 if (!IS_ERR(rt)) {
David S. Millerceb33202012-07-17 11:31:28 -07001122 __ip_do_redirect(rt, skb, &fl4, false);
David S. Miller4895c772012-07-17 04:19:00 -07001123 ip_rt_put(rt);
1124 }
David S. Millerb42597e2012-07-11 21:25:45 -07001125}
1126EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1127
David S. Millerefbc3682011-12-01 13:38:59 -05001128static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1129{
1130 struct rtable *rt = (struct rtable *) dst;
1131
David S. Millerceb33202012-07-17 11:31:28 -07001132 /* All IPV4 dsts are created with ->obsolete set to the value
1133 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1134 * into this function always.
1135 *
Timo Teräs387aa652013-05-27 20:46:31 +00001136 * When a PMTU/redirect information update invalidates a route,
1137 * this is indicated by setting obsolete to DST_OBSOLETE_KILL or
1138 * DST_OBSOLETE_DEAD by dst_free().
David S. Millerceb33202012-07-17 11:31:28 -07001139 */
Timo Teräs387aa652013-05-27 20:46:31 +00001140 if (dst->obsolete != DST_OBSOLETE_FORCE_CHK || rt_is_expired(rt))
David S. Millerefbc3682011-12-01 13:38:59 -05001141 return NULL;
Timo Teräsd11a4dc2010-03-18 23:20:20 +00001142 return dst;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143}
1144
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145static void ipv4_link_failure(struct sk_buff *skb)
1146{
1147 struct rtable *rt;
1148
1149 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1150
Eric Dumazet511c3f92009-06-02 05:14:27 +00001151 rt = skb_rtable(skb);
David S. Miller59436342012-07-10 06:58:42 -07001152 if (rt)
1153 dst_set_expires(&rt->dst, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154}
1155
Eric W. Biedermanede20592015-10-07 16:48:47 -05001156static int ip_rt_bug(struct net *net, struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001157{
Joe Perches91df42b2012-05-15 14:11:54 +00001158 pr_debug("%s: %pI4 -> %pI4, %s\n",
1159 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1160 skb->dev ? skb->dev->name : "?");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001161 kfree_skb(skb);
Dave Jonesc378a9c2011-05-21 07:16:42 +00001162 WARN_ON(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001163 return 0;
1164}
1165
1166/*
1167 We do not cache source address of outgoing interface,
1168 because it is used only by IP RR, TS and SRR options,
1169 so that it out of fast path.
1170
1171 BTW remember: "addr" is allowed to be not aligned
1172 in IP options!
1173 */
1174
David S. Miller8e363602011-05-13 17:29:41 -04001175void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176{
Al Viroa61ced52006-09-26 21:27:54 -07001177 __be32 src;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178
David S. Millerc7537962010-11-11 17:07:48 -08001179 if (rt_is_output_route(rt))
David S. Millerc5be24f2011-05-13 18:01:21 -04001180 src = ip_hdr(skb)->saddr;
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001181 else {
David S. Miller8e363602011-05-13 17:29:41 -04001182 struct fib_result res;
1183 struct flowi4 fl4;
1184 struct iphdr *iph;
1185
1186 iph = ip_hdr(skb);
1187
1188 memset(&fl4, 0, sizeof(fl4));
1189 fl4.daddr = iph->daddr;
1190 fl4.saddr = iph->saddr;
Julian Anastasovb0fe4a32011-07-23 02:00:41 +00001191 fl4.flowi4_tos = RT_TOS(iph->tos);
David S. Miller8e363602011-05-13 17:29:41 -04001192 fl4.flowi4_oif = rt->dst.dev->ifindex;
1193 fl4.flowi4_iif = skb->dev->ifindex;
1194 fl4.flowi4_mark = skb->mark;
David S. Miller5e2b61f2011-03-04 21:47:09 -08001195
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001196 rcu_read_lock();
Andy Gospodarek0eeb0752015-06-23 13:45:37 -04001197 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0)
David S. Miller436c3b62011-03-24 17:42:21 -07001198 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001199 else
David S. Millerf8126f12012-07-13 05:03:45 -07001200 src = inet_select_addr(rt->dst.dev,
1201 rt_nexthop(rt, iph->daddr),
1202 RT_SCOPE_UNIVERSE);
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001203 rcu_read_unlock();
1204 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205 memcpy(addr, &src, 4);
1206}
1207
Patrick McHardyc7066f72011-01-14 13:36:42 +01001208#ifdef CONFIG_IP_ROUTE_CLASSID
Linus Torvalds1da177e2005-04-16 15:20:36 -07001209static void set_class_tag(struct rtable *rt, u32 tag)
1210{
Changli Gaod8d1f302010-06-10 23:31:35 -07001211 if (!(rt->dst.tclassid & 0xFFFF))
1212 rt->dst.tclassid |= tag & 0xFFFF;
1213 if (!(rt->dst.tclassid & 0xFFFF0000))
1214 rt->dst.tclassid |= tag & 0xFFFF0000;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001215}
1216#endif
1217
David S. Miller0dbaee32010-12-13 12:52:14 -08001218static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1219{
1220 unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
1221
1222 if (advmss == 0) {
1223 advmss = max_t(unsigned int, dst->dev->mtu - 40,
1224 ip_rt_min_advmss);
1225 if (advmss > 65535 - 40)
1226 advmss = 65535 - 40;
1227 }
1228 return advmss;
1229}
1230
Steffen Klassertebb762f2011-11-23 02:12:51 +00001231static unsigned int ipv4_mtu(const struct dst_entry *dst)
David S. Millerd33e4552010-12-14 13:01:14 -08001232{
Steffen Klassert261663b2011-11-23 02:14:50 +00001233 const struct rtable *rt = (const struct rtable *) dst;
David S. Miller59436342012-07-10 06:58:42 -07001234 unsigned int mtu = rt->rt_pmtu;
1235
Alexander Duyck98d75c32012-08-27 06:30:01 +00001236 if (!mtu || time_after_eq(jiffies, rt->dst.expires))
David S. Miller59436342012-07-10 06:58:42 -07001237 mtu = dst_metric_raw(dst, RTAX_MTU);
Steffen Klassert618f9bc2011-11-23 02:13:31 +00001238
Steffen Klassert38d523e2013-01-16 20:55:01 +00001239 if (mtu)
Steffen Klassert618f9bc2011-11-23 02:13:31 +00001240 return mtu;
1241
1242 mtu = dst->dev->mtu;
David S. Millerd33e4552010-12-14 13:01:14 -08001243
1244 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
Julian Anastasov155e8332012-10-08 11:41:18 +00001245 if (rt->rt_uses_gateway && mtu > 576)
David S. Millerd33e4552010-12-14 13:01:14 -08001246 mtu = 576;
1247 }
1248
Eric Dumazet734d2722013-08-18 19:08:07 -07001249 return min_t(unsigned int, mtu, IP_MAX_MTU);
David S. Millerd33e4552010-12-14 13:01:14 -08001250}
1251
David S. Millerf2bb4be2012-07-17 12:20:47 -07001252static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
David S. Miller4895c772012-07-17 04:19:00 -07001253{
Eric Dumazetcaa41522014-09-03 22:21:56 -07001254 struct fnhe_hash_bucket *hash = rcu_dereference(nh->nh_exceptions);
David S. Miller4895c772012-07-17 04:19:00 -07001255 struct fib_nh_exception *fnhe;
1256 u32 hval;
1257
David S. Millerf2bb4be2012-07-17 12:20:47 -07001258 if (!hash)
1259 return NULL;
1260
David S. Millerd3a25c92012-07-17 13:23:08 -07001261 hval = fnhe_hashfun(daddr);
David S. Miller4895c772012-07-17 04:19:00 -07001262
1263 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1264 fnhe = rcu_dereference(fnhe->fnhe_next)) {
David S. Millerf2bb4be2012-07-17 12:20:47 -07001265 if (fnhe->fnhe_daddr == daddr)
1266 return fnhe;
1267 }
1268 return NULL;
1269}
David S. Miller4895c772012-07-17 04:19:00 -07001270
David S. Millercaacf052012-07-31 15:06:50 -07001271static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
David S. Millerf2bb4be2012-07-17 12:20:47 -07001272 __be32 daddr)
1273{
David S. Millercaacf052012-07-31 15:06:50 -07001274 bool ret = false;
1275
David S. Millerc5038a82012-07-31 15:02:02 -07001276 spin_lock_bh(&fnhe_lock);
Julian Anastasovaee06da2012-07-18 10:15:35 +00001277
David S. Millerc5038a82012-07-31 15:02:02 -07001278 if (daddr == fnhe->fnhe_daddr) {
Timo Teräs2ffae992013-06-27 10:27:05 +03001279 struct rtable __rcu **porig;
1280 struct rtable *orig;
Timo Teräs5aad1de2013-05-27 20:46:33 +00001281 int genid = fnhe_genid(dev_net(rt->dst.dev));
Timo Teräs2ffae992013-06-27 10:27:05 +03001282
1283 if (rt_is_input_route(rt))
1284 porig = &fnhe->fnhe_rth_input;
1285 else
1286 porig = &fnhe->fnhe_rth_output;
1287 orig = rcu_dereference(*porig);
Timo Teräs5aad1de2013-05-27 20:46:33 +00001288
1289 if (fnhe->fnhe_genid != genid) {
1290 fnhe->fnhe_genid = genid;
Steffen Klassert13d82bf2012-10-17 21:17:44 +00001291 fnhe->fnhe_gw = 0;
1292 fnhe->fnhe_pmtu = 0;
1293 fnhe->fnhe_expires = 0;
Timo Teräs2ffae992013-06-27 10:27:05 +03001294 fnhe_flush_routes(fnhe);
1295 orig = NULL;
Steffen Klassert13d82bf2012-10-17 21:17:44 +00001296 }
Timo Teräs387aa652013-05-27 20:46:31 +00001297 fill_route_from_fnhe(rt, fnhe);
1298 if (!rt->rt_gateway)
Julian Anastasov155e8332012-10-08 11:41:18 +00001299 rt->rt_gateway = daddr;
David S. Millerf2bb4be2012-07-17 12:20:47 -07001300
Timo Teräs2ffae992013-06-27 10:27:05 +03001301 if (!(rt->dst.flags & DST_NOCACHE)) {
1302 rcu_assign_pointer(*porig, rt);
1303 if (orig)
1304 rt_free(orig);
1305 ret = true;
1306 }
David S. Millerc5038a82012-07-31 15:02:02 -07001307
1308 fnhe->fnhe_stamp = jiffies;
David S. Millerc5038a82012-07-31 15:02:02 -07001309 }
1310 spin_unlock_bh(&fnhe_lock);
David S. Millercaacf052012-07-31 15:06:50 -07001311
1312 return ret;
Eric Dumazet54764bb2012-07-31 01:08:23 +00001313}
1314
David S. Millercaacf052012-07-31 15:06:50 -07001315static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt)
David S. Millerf2bb4be2012-07-17 12:20:47 -07001316{
Eric Dumazetd26b3a72012-07-31 05:45:30 +00001317 struct rtable *orig, *prev, **p;
David S. Millercaacf052012-07-31 15:06:50 -07001318 bool ret = true;
David S. Millerf2bb4be2012-07-17 12:20:47 -07001319
Eric Dumazetd26b3a72012-07-31 05:45:30 +00001320 if (rt_is_input_route(rt)) {
Eric Dumazet54764bb2012-07-31 01:08:23 +00001321 p = (struct rtable **)&nh->nh_rth_input;
Eric Dumazetd26b3a72012-07-31 05:45:30 +00001322 } else {
Christoph Lameter903ceff2014-08-17 12:30:35 -05001323 p = (struct rtable **)raw_cpu_ptr(nh->nh_pcpu_rth_output);
Eric Dumazetd26b3a72012-07-31 05:45:30 +00001324 }
David S. Millerf2bb4be2012-07-17 12:20:47 -07001325 orig = *p;
1326
1327 prev = cmpxchg(p, orig, rt);
1328 if (prev == orig) {
David S. Millerf2bb4be2012-07-17 12:20:47 -07001329 if (orig)
Eric Dumazet54764bb2012-07-31 01:08:23 +00001330 rt_free(orig);
Julian Anastasov155e8332012-10-08 11:41:18 +00001331 } else
David S. Millercaacf052012-07-31 15:06:50 -07001332 ret = false;
David S. Millercaacf052012-07-31 15:06:50 -07001333
1334 return ret;
1335}
1336
Eric Dumazet5055c372015-01-14 15:17:06 -08001337struct uncached_list {
1338 spinlock_t lock;
1339 struct list_head head;
1340};
1341
1342static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt_uncached_list);
David S. Millercaacf052012-07-31 15:06:50 -07001343
1344static void rt_add_uncached_list(struct rtable *rt)
1345{
Eric Dumazet5055c372015-01-14 15:17:06 -08001346 struct uncached_list *ul = raw_cpu_ptr(&rt_uncached_list);
1347
1348 rt->rt_uncached_list = ul;
1349
1350 spin_lock_bh(&ul->lock);
1351 list_add_tail(&rt->rt_uncached, &ul->head);
1352 spin_unlock_bh(&ul->lock);
David S. Millercaacf052012-07-31 15:06:50 -07001353}
1354
1355static void ipv4_dst_destroy(struct dst_entry *dst)
1356{
1357 struct rtable *rt = (struct rtable *) dst;
1358
Eric Dumazet78df76a2012-08-24 05:40:47 +00001359 if (!list_empty(&rt->rt_uncached)) {
Eric Dumazet5055c372015-01-14 15:17:06 -08001360 struct uncached_list *ul = rt->rt_uncached_list;
1361
1362 spin_lock_bh(&ul->lock);
David S. Millercaacf052012-07-31 15:06:50 -07001363 list_del(&rt->rt_uncached);
Eric Dumazet5055c372015-01-14 15:17:06 -08001364 spin_unlock_bh(&ul->lock);
David S. Millercaacf052012-07-31 15:06:50 -07001365 }
1366}
1367
1368void rt_flush_dev(struct net_device *dev)
1369{
Eric Dumazet5055c372015-01-14 15:17:06 -08001370 struct net *net = dev_net(dev);
1371 struct rtable *rt;
1372 int cpu;
David S. Millercaacf052012-07-31 15:06:50 -07001373
Eric Dumazet5055c372015-01-14 15:17:06 -08001374 for_each_possible_cpu(cpu) {
1375 struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
1376
1377 spin_lock_bh(&ul->lock);
1378 list_for_each_entry(rt, &ul->head, rt_uncached) {
David S. Millercaacf052012-07-31 15:06:50 -07001379 if (rt->dst.dev != dev)
1380 continue;
1381 rt->dst.dev = net->loopback_dev;
1382 dev_hold(rt->dst.dev);
1383 dev_put(dev);
1384 }
Eric Dumazet5055c372015-01-14 15:17:06 -08001385 spin_unlock_bh(&ul->lock);
David S. Miller4895c772012-07-17 04:19:00 -07001386 }
1387}
1388
Eric Dumazet4331deb2012-07-25 05:11:23 +00001389static bool rt_cache_valid(const struct rtable *rt)
David S. Millerd2d68ba2012-07-17 12:58:50 -07001390{
Eric Dumazet4331deb2012-07-25 05:11:23 +00001391 return rt &&
1392 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1393 !rt_is_expired(rt);
David S. Millerd2d68ba2012-07-17 12:58:50 -07001394}
1395
David S. Millerf2bb4be2012-07-17 12:20:47 -07001396static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
David S. Miller5e2b61f2011-03-04 21:47:09 -08001397 const struct fib_result *res,
David S. Millerf2bb4be2012-07-17 12:20:47 -07001398 struct fib_nh_exception *fnhe,
David S. Miller982721f2011-02-16 21:44:24 -08001399 struct fib_info *fi, u16 type, u32 itag)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001400{
David S. Millercaacf052012-07-31 15:06:50 -07001401 bool cached = false;
1402
Linus Torvalds1da177e2005-04-16 15:20:36 -07001403 if (fi) {
David S. Miller4895c772012-07-17 04:19:00 -07001404 struct fib_nh *nh = &FIB_RES_NH(*res);
1405
Julian Anastasov155e8332012-10-08 11:41:18 +00001406 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) {
David S. Miller4895c772012-07-17 04:19:00 -07001407 rt->rt_gateway = nh->nh_gw;
Julian Anastasov155e8332012-10-08 11:41:18 +00001408 rt->rt_uses_gateway = 1;
1409 }
David S. Miller28605832012-07-17 14:55:59 -07001410 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
Patrick McHardyc7066f72011-01-14 13:36:42 +01001411#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Millerf2bb4be2012-07-17 12:20:47 -07001412 rt->dst.tclassid = nh->nh_tclassid;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413#endif
Jiri Benc61adedf2015-08-20 13:56:25 +02001414 rt->dst.lwtstate = lwtstate_get(nh->nh_lwtstate);
David S. Millerc5038a82012-07-31 15:02:02 -07001415 if (unlikely(fnhe))
David S. Millercaacf052012-07-31 15:06:50 -07001416 cached = rt_bind_exception(rt, fnhe, daddr);
David S. Millerc5038a82012-07-31 15:02:02 -07001417 else if (!(rt->dst.flags & DST_NOCACHE))
David S. Millercaacf052012-07-31 15:06:50 -07001418 cached = rt_cache_route(nh, rt);
Julian Anastasov155e8332012-10-08 11:41:18 +00001419 if (unlikely(!cached)) {
1420 /* Routes we intend to cache in nexthop exception or
1421 * FIB nexthop have the DST_NOCACHE bit clear.
1422 * However, if we are unsuccessful at storing this
1423 * route into the cache we really need to set it.
1424 */
1425 rt->dst.flags |= DST_NOCACHE;
1426 if (!rt->rt_gateway)
1427 rt->rt_gateway = daddr;
1428 rt_add_uncached_list(rt);
1429 }
1430 } else
David S. Millercaacf052012-07-31 15:06:50 -07001431 rt_add_uncached_list(rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432
Patrick McHardyc7066f72011-01-14 13:36:42 +01001433#ifdef CONFIG_IP_ROUTE_CLASSID
Linus Torvalds1da177e2005-04-16 15:20:36 -07001434#ifdef CONFIG_IP_MULTIPLE_TABLES
David S. Miller85b91b02012-07-13 08:21:29 -07001435 set_class_tag(rt, res->tclassid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001436#endif
1437 set_class_tag(rt, itag);
1438#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001439}
1440
David S. Miller5c1e6aa2011-04-28 14:13:38 -07001441static struct rtable *rt_dst_alloc(struct net_device *dev,
David Ahernd08c4f32015-09-02 13:58:34 -07001442 unsigned int flags, u16 type,
David S. Millerf2bb4be2012-07-17 12:20:47 -07001443 bool nopolicy, bool noxfrm, bool will_cache)
David S. Miller0c4dcd52011-02-17 15:42:37 -08001444{
David Ahernd08c4f32015-09-02 13:58:34 -07001445 struct rtable *rt;
1446
1447 rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
1448 (will_cache ? 0 : (DST_HOST | DST_NOCACHE)) |
1449 (nopolicy ? DST_NOPOLICY : 0) |
1450 (noxfrm ? DST_NOXFRM : 0));
1451
1452 if (rt) {
1453 rt->rt_genid = rt_genid_ipv4(dev_net(dev));
1454 rt->rt_flags = flags;
1455 rt->rt_type = type;
1456 rt->rt_is_input = 0;
1457 rt->rt_iif = 0;
1458 rt->rt_pmtu = 0;
1459 rt->rt_gateway = 0;
1460 rt->rt_uses_gateway = 0;
David Ahernb7503e02015-09-02 13:58:35 -07001461 rt->rt_table_id = 0;
David Ahernd08c4f32015-09-02 13:58:34 -07001462 INIT_LIST_HEAD(&rt->rt_uncached);
1463
1464 rt->dst.output = ip_output;
1465 if (flags & RTCF_LOCAL)
1466 rt->dst.input = ip_local_deliver;
1467 }
1468
1469 return rt;
David S. Miller0c4dcd52011-02-17 15:42:37 -08001470}
1471
Eric Dumazet96d36222010-06-02 19:21:31 +00001472/* called in rcu_read_lock() section */
Al Viro9e12bb22006-09-26 21:25:20 -07001473static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474 u8 tos, struct net_device *dev, int our)
1475{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476 struct rtable *rth;
Eric Dumazet96d36222010-06-02 19:21:31 +00001477 struct in_device *in_dev = __in_dev_get_rcu(dev);
David Ahernd08c4f32015-09-02 13:58:34 -07001478 unsigned int flags = RTCF_MULTICAST;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479 u32 itag = 0;
Eric Dumazetb5f7e752010-06-02 12:05:27 +00001480 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001481
1482 /* Primary sanity checks. */
1483
Ian Morris51456b22015-04-03 09:17:26 +01001484 if (!in_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001485 return -EINVAL;
1486
Jan Engelhardt1e637c72008-01-21 03:18:08 -08001487 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
Thomas Grafd0daebc32012-06-12 00:44:01 +00001488 skb->protocol != htons(ETH_P_IP))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001489 goto e_inval;
1490
Alexander Duyck75fea732015-09-28 11:10:38 -07001491 if (ipv4_is_loopback(saddr) && !IN_DEV_ROUTE_LOCALNET(in_dev))
1492 goto e_inval;
Thomas Grafd0daebc32012-06-12 00:44:01 +00001493
Joe Perchesf97c1e02007-12-16 13:45:43 -08001494 if (ipv4_is_zeronet(saddr)) {
1495 if (!ipv4_is_local_multicast(daddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496 goto e_inval;
Eric Dumazetb5f7e752010-06-02 12:05:27 +00001497 } else {
David S. Miller9e56e382012-06-28 18:54:02 -07001498 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1499 in_dev, &itag);
Eric Dumazetb5f7e752010-06-02 12:05:27 +00001500 if (err < 0)
1501 goto e_err;
1502 }
David Ahernd08c4f32015-09-02 13:58:34 -07001503 if (our)
1504 flags |= RTCF_LOCAL;
1505
1506 rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST,
David S. Millerf2bb4be2012-07-17 12:20:47 -07001507 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001508 if (!rth)
1509 goto e_nobufs;
1510
Patrick McHardyc7066f72011-01-14 13:36:42 +01001511#ifdef CONFIG_IP_ROUTE_CLASSID
Changli Gaod8d1f302010-06-10 23:31:35 -07001512 rth->dst.tclassid = itag;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001513#endif
David S. Millercf911662011-04-28 14:31:47 -07001514 rth->dst.output = ip_rt_bug;
David S. Miller9917e1e82012-07-17 14:44:26 -07001515 rth->rt_is_input= 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001516
1517#ifdef CONFIG_IP_MROUTE
Joe Perchesf97c1e02007-12-16 13:45:43 -08001518 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
Changli Gaod8d1f302010-06-10 23:31:35 -07001519 rth->dst.input = ip_mr_input;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520#endif
1521 RT_CACHE_STAT_INC(in_slow_mc);
1522
David S. Miller89aef892012-07-17 11:00:09 -07001523 skb_dst_set(skb, &rth->dst);
1524 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001525
1526e_nobufs:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527 return -ENOBUFS;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001528e_inval:
Eric Dumazet96d36222010-06-02 19:21:31 +00001529 return -EINVAL;
Eric Dumazetb5f7e752010-06-02 12:05:27 +00001530e_err:
Eric Dumazetb5f7e752010-06-02 12:05:27 +00001531 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001532}
1533
1534
1535static void ip_handle_martian_source(struct net_device *dev,
1536 struct in_device *in_dev,
1537 struct sk_buff *skb,
Al Viro9e12bb22006-09-26 21:25:20 -07001538 __be32 daddr,
1539 __be32 saddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540{
1541 RT_CACHE_STAT_INC(in_martian_src);
1542#ifdef CONFIG_IP_ROUTE_VERBOSE
1543 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1544 /*
1545 * RFC1812 recommendation, if source is martian,
1546 * the only hint is MAC header.
1547 */
Joe Perches058bd4d2012-03-11 18:36:11 +00001548 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
Harvey Harrison673d57e2008-10-31 00:53:57 -07001549 &daddr, &saddr, dev->name);
Arnaldo Carvalho de Melo98e399f2007-03-19 15:33:04 -07001550 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
Joe Perches058bd4d2012-03-11 18:36:11 +00001551 print_hex_dump(KERN_WARNING, "ll header: ",
1552 DUMP_PREFIX_OFFSET, 16, 1,
1553 skb_mac_header(skb),
1554 dev->hard_header_len, true);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 }
1556 }
1557#endif
1558}
1559
Xin Longdeed49d2016-02-18 21:21:19 +08001560static void ip_del_fnhe(struct fib_nh *nh, __be32 daddr)
1561{
1562 struct fnhe_hash_bucket *hash;
1563 struct fib_nh_exception *fnhe, __rcu **fnhe_p;
1564 u32 hval = fnhe_hashfun(daddr);
1565
1566 spin_lock_bh(&fnhe_lock);
1567
1568 hash = rcu_dereference_protected(nh->nh_exceptions,
1569 lockdep_is_held(&fnhe_lock));
1570 hash += hval;
1571
1572 fnhe_p = &hash->chain;
1573 fnhe = rcu_dereference_protected(*fnhe_p, lockdep_is_held(&fnhe_lock));
1574 while (fnhe) {
1575 if (fnhe->fnhe_daddr == daddr) {
1576 rcu_assign_pointer(*fnhe_p, rcu_dereference_protected(
1577 fnhe->fnhe_next, lockdep_is_held(&fnhe_lock)));
1578 fnhe_flush_routes(fnhe);
1579 kfree_rcu(fnhe, rcu);
1580 break;
1581 }
1582 fnhe_p = &fnhe->fnhe_next;
1583 fnhe = rcu_dereference_protected(fnhe->fnhe_next,
1584 lockdep_is_held(&fnhe_lock));
1585 }
1586
1587 spin_unlock_bh(&fnhe_lock);
1588}
1589
Eric Dumazet47360222010-06-03 04:13:21 +00001590/* called in rcu_read_lock() section */
Stephen Hemminger5969f712008-04-10 01:52:09 -07001591static int __mkroute_input(struct sk_buff *skb,
David S. Miller982721f2011-02-16 21:44:24 -08001592 const struct fib_result *res,
Stephen Hemminger5969f712008-04-10 01:52:09 -07001593 struct in_device *in_dev,
David S. Millerc6cffba2012-07-26 11:14:38 +00001594 __be32 daddr, __be32 saddr, u32 tos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001595{
Timo Teräs2ffae992013-06-27 10:27:05 +03001596 struct fib_nh_exception *fnhe;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 struct rtable *rth;
1598 int err;
1599 struct in_device *out_dev;
David S. Millerd2d68ba2012-07-17 12:58:50 -07001600 bool do_cache;
Li RongQingfbdc0ad2014-05-22 16:36:55 +08001601 u32 itag = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001602
1603 /* get a working reference to the output device */
Eric Dumazet47360222010-06-03 04:13:21 +00001604 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
Ian Morris51456b22015-04-03 09:17:26 +01001605 if (!out_dev) {
Joe Perchese87cc472012-05-13 21:56:26 +00001606 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001607 return -EINVAL;
1608 }
1609
Michael Smith5c04c812011-04-07 04:51:50 +00001610 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
David S. Miller9e56e382012-06-28 18:54:02 -07001611 in_dev->dev, in_dev, &itag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612 if (err < 0) {
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001613 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614 saddr);
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001615
Linus Torvalds1da177e2005-04-16 15:20:36 -07001616 goto cleanup;
1617 }
1618
Julian Anastasove81da0e2012-10-08 11:41:15 +00001619 do_cache = res->fi && !itag;
1620 if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
Hannes Frederic Sowadf4d9252015-01-23 12:01:26 +01001621 skb->protocol == htons(ETH_P_IP) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07001622 (IN_DEV_SHARED_MEDIA(out_dev) ||
Hannes Frederic Sowadf4d9252015-01-23 12:01:26 +01001623 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1624 IPCB(skb)->flags |= IPSKB_DOREDIRECT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625
1626 if (skb->protocol != htons(ETH_P_IP)) {
1627 /* Not IP (i.e. ARP). Do not create route, if it is
1628 * invalid for proxy arp. DNAT routes are always valid.
Jesper Dangaard Brouer65324142010-01-05 05:50:47 +00001629 *
1630 * Proxy arp feature have been extended to allow, ARP
1631 * replies back to the same interface, to support
1632 * Private VLAN switch technologies. See arp.c.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633 */
Jesper Dangaard Brouer65324142010-01-05 05:50:47 +00001634 if (out_dev == in_dev &&
1635 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636 err = -EINVAL;
1637 goto cleanup;
1638 }
1639 }
1640
Timo Teräs2ffae992013-06-27 10:27:05 +03001641 fnhe = find_exception(&FIB_RES_NH(*res), daddr);
Julian Anastasove81da0e2012-10-08 11:41:15 +00001642 if (do_cache) {
Xin Longdeed49d2016-02-18 21:21:19 +08001643 if (fnhe) {
Timo Teräs2ffae992013-06-27 10:27:05 +03001644 rth = rcu_dereference(fnhe->fnhe_rth_input);
Xin Longdeed49d2016-02-18 21:21:19 +08001645 if (rth && rth->dst.expires &&
1646 time_after(jiffies, rth->dst.expires)) {
1647 ip_del_fnhe(&FIB_RES_NH(*res), daddr);
1648 fnhe = NULL;
1649 } else {
1650 goto rt_cache;
1651 }
1652 }
Timo Teräs2ffae992013-06-27 10:27:05 +03001653
Xin Longdeed49d2016-02-18 21:21:19 +08001654 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1655
1656rt_cache:
Julian Anastasove81da0e2012-10-08 11:41:15 +00001657 if (rt_cache_valid(rth)) {
1658 skb_dst_set_noref(skb, &rth->dst);
1659 goto out;
David S. Millerd2d68ba2012-07-17 12:58:50 -07001660 }
1661 }
David S. Millerf2bb4be2012-07-17 12:20:47 -07001662
David Ahernd08c4f32015-09-02 13:58:34 -07001663 rth = rt_dst_alloc(out_dev->dev, 0, res->type,
David S. Miller5c1e6aa2011-04-28 14:13:38 -07001664 IN_DEV_CONF_GET(in_dev, NOPOLICY),
David S. Millerd2d68ba2012-07-17 12:58:50 -07001665 IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 if (!rth) {
1667 err = -ENOBUFS;
1668 goto cleanup;
1669 }
1670
David S. Miller9917e1e82012-07-17 14:44:26 -07001671 rth->rt_is_input = 1;
David Ahernb7503e02015-09-02 13:58:35 -07001672 if (res->table)
1673 rth->rt_table_id = res->table->tb_id;
Duan Jionga6254862014-02-17 15:23:43 +08001674 RT_CACHE_STAT_INC(in_slow_tot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001675
Changli Gaod8d1f302010-06-10 23:31:35 -07001676 rth->dst.input = ip_forward;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001677
Timo Teräs2ffae992013-06-27 10:27:05 +03001678 rt_set_nexthop(rth, daddr, res, fnhe, res->fi, res->type, itag);
Jiri Benc61adedf2015-08-20 13:56:25 +02001679 if (lwtunnel_output_redirect(rth->dst.lwtstate)) {
1680 rth->dst.lwtstate->orig_output = rth->dst.output;
Roopa Prabhu8602a622015-07-21 10:43:50 +02001681 rth->dst.output = lwtunnel_output;
Tom Herbert25368622015-08-17 13:42:24 -07001682 }
Jiri Benc61adedf2015-08-20 13:56:25 +02001683 if (lwtunnel_input_redirect(rth->dst.lwtstate)) {
1684 rth->dst.lwtstate->orig_input = rth->dst.input;
Tom Herbert25368622015-08-17 13:42:24 -07001685 rth->dst.input = lwtunnel_input;
1686 }
David S. Millerc6cffba2012-07-26 11:14:38 +00001687 skb_dst_set(skb, &rth->dst);
David S. Millerd2d68ba2012-07-17 12:58:50 -07001688out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689 err = 0;
1690 cleanup:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001691 return err;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001692}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001693
Peter Nørlund79a13152015-09-30 10:12:22 +02001694#ifdef CONFIG_IP_ROUTE_MULTIPATH
1695
1696/* To make ICMP packets follow the right flow, the multipath hash is
1697 * calculated from the inner IP addresses in reverse order.
1698 */
1699static int ip_multipath_icmp_hash(struct sk_buff *skb)
1700{
1701 const struct iphdr *outer_iph = ip_hdr(skb);
1702 struct icmphdr _icmph;
1703 const struct icmphdr *icmph;
1704 struct iphdr _inner_iph;
1705 const struct iphdr *inner_iph;
1706
1707 if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0))
1708 goto standard_hash;
1709
1710 icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph),
1711 &_icmph);
1712 if (!icmph)
1713 goto standard_hash;
1714
1715 if (icmph->type != ICMP_DEST_UNREACH &&
1716 icmph->type != ICMP_REDIRECT &&
1717 icmph->type != ICMP_TIME_EXCEEDED &&
1718 icmph->type != ICMP_PARAMETERPROB) {
1719 goto standard_hash;
1720 }
1721
1722 inner_iph = skb_header_pointer(skb,
1723 outer_iph->ihl * 4 + sizeof(_icmph),
1724 sizeof(_inner_iph), &_inner_iph);
1725 if (!inner_iph)
1726 goto standard_hash;
1727
1728 return fib_multipath_hash(inner_iph->daddr, inner_iph->saddr);
1729
1730standard_hash:
1731 return fib_multipath_hash(outer_iph->saddr, outer_iph->daddr);
1732}
1733
1734#endif /* CONFIG_IP_ROUTE_MULTIPATH */
1735
Stephen Hemminger5969f712008-04-10 01:52:09 -07001736static int ip_mkroute_input(struct sk_buff *skb,
1737 struct fib_result *res,
David S. Miller68a5e3d2011-03-11 20:07:33 -05001738 const struct flowi4 *fl4,
Stephen Hemminger5969f712008-04-10 01:52:09 -07001739 struct in_device *in_dev,
1740 __be32 daddr, __be32 saddr, u32 tos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001741{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742#ifdef CONFIG_IP_ROUTE_MULTIPATH
Peter Nørlund0e884c72015-09-30 10:12:21 +02001743 if (res->fi && res->fi->fib_nhs > 1) {
1744 int h;
1745
Peter Nørlund79a13152015-09-30 10:12:22 +02001746 if (unlikely(ip_hdr(skb)->protocol == IPPROTO_ICMP))
1747 h = ip_multipath_icmp_hash(skb);
1748 else
1749 h = fib_multipath_hash(saddr, daddr);
Peter Nørlund0e884c72015-09-30 10:12:21 +02001750 fib_select_multipath(res, h);
1751 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001752#endif
1753
1754 /* create a routing cache entry */
David S. Millerc6cffba2012-07-26 11:14:38 +00001755 return __mkroute_input(skb, res, in_dev, daddr, saddr, tos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001756}
1757
Linus Torvalds1da177e2005-04-16 15:20:36 -07001758/*
1759 * NOTE. We drop all the packets that has local source
1760 * addresses, because every properly looped back packet
1761 * must have correct destination already attached by output routine.
1762 *
1763 * Such approach solves two big problems:
1764 * 1. Not simplex devices are handled properly.
1765 * 2. IP spoofing attempts are filtered with 100% of guarantee.
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001766 * called with rcu_read_lock()
Linus Torvalds1da177e2005-04-16 15:20:36 -07001767 */
1768
Al Viro9e12bb22006-09-26 21:25:20 -07001769static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
David S. Millerc10237e2012-06-27 17:05:06 -07001770 u8 tos, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771{
1772 struct fib_result res;
Eric Dumazet96d36222010-06-02 19:21:31 +00001773 struct in_device *in_dev = __in_dev_get_rcu(dev);
Thomas Graf1b7179d2015-07-21 10:43:59 +02001774 struct ip_tunnel_info *tun_info;
David S. Miller68a5e3d2011-03-11 20:07:33 -05001775 struct flowi4 fl4;
Eric Dumazet95c96172012-04-15 05:58:06 +00001776 unsigned int flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001777 u32 itag = 0;
Eric Dumazet95c96172012-04-15 05:58:06 +00001778 struct rtable *rth;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001779 int err = -EINVAL;
Daniel Baluta5e73ea12012-04-15 01:34:41 +00001780 struct net *net = dev_net(dev);
David S. Millerd2d68ba2012-07-17 12:58:50 -07001781 bool do_cache;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001782
1783 /* IP on this device is disabled. */
1784
1785 if (!in_dev)
1786 goto out;
1787
1788 /* Check for the most weird martians, which can be not detected
1789 by fib_lookup.
1790 */
1791
Jiri Benc61adedf2015-08-20 13:56:25 +02001792 tun_info = skb_tunnel_info(skb);
Jiri Benc46fa0622015-08-28 20:48:19 +02001793 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
Thomas Graf1b7179d2015-07-21 10:43:59 +02001794 fl4.flowi4_tun_key.tun_id = tun_info->key.tun_id;
1795 else
1796 fl4.flowi4_tun_key.tun_id = 0;
Thomas Graff38a9eb2015-07-21 10:43:56 +02001797 skb_dst_drop(skb);
1798
Thomas Grafd0daebc32012-06-12 00:44:01 +00001799 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001800 goto martian_source;
1801
David S. Millerd2d68ba2012-07-17 12:58:50 -07001802 res.fi = NULL;
David Ahernbde6f9d2015-09-16 10:16:39 -06001803 res.table = NULL;
Andy Walls27a954b2010-10-17 15:11:22 +00001804 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001805 goto brd_input;
1806
1807 /* Accept zero addresses only to limited broadcast;
1808 * I even do not know to fix it or not. Waiting for complains :-)
1809 */
Joe Perchesf97c1e02007-12-16 13:45:43 -08001810 if (ipv4_is_zeronet(saddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001811 goto martian_source;
1812
Thomas Grafd0daebc32012-06-12 00:44:01 +00001813 if (ipv4_is_zeronet(daddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001814 goto martian_destination;
1815
Eric Dumazet9eb43e72012-08-03 21:27:25 +00001816 /* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(),
1817 * and call it once if daddr or/and saddr are loopback addresses
1818 */
1819 if (ipv4_is_loopback(daddr)) {
1820 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
Thomas Grafd0daebc32012-06-12 00:44:01 +00001821 goto martian_destination;
Eric Dumazet9eb43e72012-08-03 21:27:25 +00001822 } else if (ipv4_is_loopback(saddr)) {
1823 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
Thomas Grafd0daebc32012-06-12 00:44:01 +00001824 goto martian_source;
1825 }
1826
Linus Torvalds1da177e2005-04-16 15:20:36 -07001827 /*
1828 * Now we are ready to route packet.
1829 */
David S. Miller68a5e3d2011-03-11 20:07:33 -05001830 fl4.flowi4_oif = 0;
David Ahern385add92015-09-29 20:07:13 -07001831 fl4.flowi4_iif = l3mdev_fib_oif_rcu(dev);
David S. Miller68a5e3d2011-03-11 20:07:33 -05001832 fl4.flowi4_mark = skb->mark;
1833 fl4.flowi4_tos = tos;
1834 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
David Ahernb84f7872015-09-29 19:07:07 -07001835 fl4.flowi4_flags = 0;
David S. Miller68a5e3d2011-03-11 20:07:33 -05001836 fl4.daddr = daddr;
1837 fl4.saddr = saddr;
Andy Gospodarek0eeb0752015-06-23 13:45:37 -04001838 err = fib_lookup(net, &fl4, &res, 0);
Duan Jiongcd0f0b92014-02-14 18:26:22 +08001839 if (err != 0) {
1840 if (!IN_DEV_FORWARD(in_dev))
1841 err = -EHOSTUNREACH;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001842 goto no_route;
Duan Jiongcd0f0b92014-02-14 18:26:22 +08001843 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001844
1845 if (res.type == RTN_BROADCAST)
1846 goto brd_input;
1847
1848 if (res.type == RTN_LOCAL) {
Michael Smith5c04c812011-04-07 04:51:50 +00001849 err = fib_validate_source(skb, saddr, daddr, tos,
Cong Wang0d5edc62014-04-15 16:25:35 -07001850 0, dev, in_dev, &itag);
Eric Dumazetb5f7e752010-06-02 12:05:27 +00001851 if (err < 0)
David Ahern0d753962015-09-28 11:10:44 -07001852 goto martian_source;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001853 goto local_input;
1854 }
1855
Duan Jiongcd0f0b92014-02-14 18:26:22 +08001856 if (!IN_DEV_FORWARD(in_dev)) {
1857 err = -EHOSTUNREACH;
David S. Miller251da412012-06-26 16:27:09 -07001858 goto no_route;
Duan Jiongcd0f0b92014-02-14 18:26:22 +08001859 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001860 if (res.type != RTN_UNICAST)
1861 goto martian_destination;
1862
David S. Miller68a5e3d2011-03-11 20:07:33 -05001863 err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001864out: return err;
1865
1866brd_input:
1867 if (skb->protocol != htons(ETH_P_IP))
1868 goto e_inval;
1869
David S. Miller41347dc2012-06-28 04:05:27 -07001870 if (!ipv4_is_zeronet(saddr)) {
David S. Miller9e56e382012-06-28 18:54:02 -07001871 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1872 in_dev, &itag);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001873 if (err < 0)
David Ahern0d753962015-09-28 11:10:44 -07001874 goto martian_source;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001875 }
1876 flags |= RTCF_BROADCAST;
1877 res.type = RTN_BROADCAST;
1878 RT_CACHE_STAT_INC(in_brd);
1879
1880local_input:
David S. Millerd2d68ba2012-07-17 12:58:50 -07001881 do_cache = false;
1882 if (res.fi) {
David S. Millerfe3edf42012-07-23 13:22:20 -07001883 if (!itag) {
Eric Dumazet54764bb2012-07-31 01:08:23 +00001884 rth = rcu_dereference(FIB_RES_NH(res).nh_rth_input);
David S. Millerd2d68ba2012-07-17 12:58:50 -07001885 if (rt_cache_valid(rth)) {
David S. Millerc6cffba2012-07-26 11:14:38 +00001886 skb_dst_set_noref(skb, &rth->dst);
1887 err = 0;
1888 goto out;
David S. Millerd2d68ba2012-07-17 12:58:50 -07001889 }
1890 do_cache = true;
1891 }
1892 }
1893
David Ahernd08c4f32015-09-02 13:58:34 -07001894 rth = rt_dst_alloc(net->loopback_dev, flags | RTCF_LOCAL, res.type,
David S. Millerd2d68ba2012-07-17 12:58:50 -07001895 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001896 if (!rth)
1897 goto e_nobufs;
1898
Changli Gaod8d1f302010-06-10 23:31:35 -07001899 rth->dst.output= ip_rt_bug;
David S. Millercf911662011-04-28 14:31:47 -07001900#ifdef CONFIG_IP_ROUTE_CLASSID
1901 rth->dst.tclassid = itag;
1902#endif
David S. Miller9917e1e82012-07-17 14:44:26 -07001903 rth->rt_is_input = 1;
David Ahernb7503e02015-09-02 13:58:35 -07001904 if (res.table)
1905 rth->rt_table_id = res.table->tb_id;
Roopa Prabhu571e7222015-07-21 10:43:47 +02001906
Duan Jionga6254862014-02-17 15:23:43 +08001907 RT_CACHE_STAT_INC(in_slow_tot);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001908 if (res.type == RTN_UNREACHABLE) {
Changli Gaod8d1f302010-06-10 23:31:35 -07001909 rth->dst.input= ip_error;
1910 rth->dst.error= -err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001911 rth->rt_flags &= ~RTCF_LOCAL;
1912 }
Alexei Starovoitovdcdfdf52013-11-19 19:12:34 -08001913 if (do_cache) {
1914 if (unlikely(!rt_cache_route(&FIB_RES_NH(res), rth))) {
1915 rth->dst.flags |= DST_NOCACHE;
1916 rt_add_uncached_list(rth);
1917 }
1918 }
David S. Miller89aef892012-07-17 11:00:09 -07001919 skb_dst_set(skb, &rth->dst);
David S. Millerb23dd4f2011-03-02 14:31:35 -08001920 err = 0;
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001921 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001922
1923no_route:
1924 RT_CACHE_STAT_INC(in_no_route);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001925 res.type = RTN_UNREACHABLE;
Nicolas Cavallarifa19c2b02014-10-30 10:09:53 +01001926 res.fi = NULL;
David Ahernbde6f9d2015-09-16 10:16:39 -06001927 res.table = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001928 goto local_input;
1929
1930 /*
1931 * Do not cache martian addresses: they should be logged (RFC1812)
1932 */
1933martian_destination:
1934 RT_CACHE_STAT_INC(in_martian_dst);
1935#ifdef CONFIG_IP_ROUTE_VERBOSE
Joe Perchese87cc472012-05-13 21:56:26 +00001936 if (IN_DEV_LOG_MARTIANS(in_dev))
1937 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
1938 &daddr, &saddr, dev->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939#endif
Dietmar Eggemann2c2910a2005-06-28 13:06:23 -07001940
Linus Torvalds1da177e2005-04-16 15:20:36 -07001941e_inval:
1942 err = -EINVAL;
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001943 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001944
1945e_nobufs:
1946 err = -ENOBUFS;
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001947 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001948
1949martian_source:
1950 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00001951 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001952}
1953
David S. Millerc6cffba2012-07-26 11:14:38 +00001954int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1955 u8 tos, struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001956{
Eric Dumazet96d36222010-06-02 19:21:31 +00001957 int res;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001958
Eric Dumazet96d36222010-06-02 19:21:31 +00001959 rcu_read_lock();
1960
Linus Torvalds1da177e2005-04-16 15:20:36 -07001961 /* Multicast recognition logic is moved from route cache to here.
1962 The problem was that too many Ethernet cards have broken/missing
1963 hardware multicast filters :-( As result the host on multicasting
1964 network acquires a lot of useless route cache entries, sort of
1965 SDR messages from all the world. Now we try to get rid of them.
1966 Really, provided software IP multicast filter is organized
1967 reasonably (at least, hashed), it does not result in a slowdown
1968 comparing with route cache reject entries.
1969 Note, that multicast routers are not affected, because
1970 route cache entry is created eventually.
1971 */
Joe Perchesf97c1e02007-12-16 13:45:43 -08001972 if (ipv4_is_multicast(daddr)) {
Eric Dumazet96d36222010-06-02 19:21:31 +00001973 struct in_device *in_dev = __in_dev_get_rcu(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001974
Eric Dumazet96d36222010-06-02 19:21:31 +00001975 if (in_dev) {
David S. Millerdbdd9a52011-03-10 16:34:38 -08001976 int our = ip_check_mc_rcu(in_dev, daddr, saddr,
1977 ip_hdr(skb)->protocol);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001978 if (our
1979#ifdef CONFIG_IP_MROUTE
Joe Perches9d4fb272009-11-23 10:41:23 -08001980 ||
1981 (!ipv4_is_local_multicast(daddr) &&
1982 IN_DEV_MFORWARD(in_dev))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001983#endif
Joe Perches9d4fb272009-11-23 10:41:23 -08001984 ) {
Eric Dumazet96d36222010-06-02 19:21:31 +00001985 int res = ip_route_input_mc(skb, daddr, saddr,
1986 tos, dev, our);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001987 rcu_read_unlock();
Eric Dumazet96d36222010-06-02 19:21:31 +00001988 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001989 }
1990 }
1991 rcu_read_unlock();
1992 return -EINVAL;
1993 }
David S. Millerc10237e2012-06-27 17:05:06 -07001994 res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
Eric Dumazet96d36222010-06-02 19:21:31 +00001995 rcu_read_unlock();
1996 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001997}
David S. Millerc6cffba2012-07-26 11:14:38 +00001998EXPORT_SYMBOL(ip_route_input_noref);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001999
Eric Dumazetebc0ffa2010-10-05 10:41:36 +00002000/* called with rcu_read_lock() */
David S. Miller982721f2011-02-16 21:44:24 -08002001static struct rtable *__mkroute_output(const struct fib_result *res,
David Miller1a00fee2012-07-01 02:02:56 +00002002 const struct flowi4 *fl4, int orig_oif,
Julian Anastasovf61759e2011-12-02 11:39:42 +00002003 struct net_device *dev_out,
David S. Miller5ada5522011-02-17 15:29:00 -08002004 unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002005{
David S. Miller982721f2011-02-16 21:44:24 -08002006 struct fib_info *fi = res->fi;
David S. Millerf2bb4be2012-07-17 12:20:47 -07002007 struct fib_nh_exception *fnhe;
David S. Miller5ada5522011-02-17 15:29:00 -08002008 struct in_device *in_dev;
David S. Miller982721f2011-02-16 21:44:24 -08002009 u16 type = res->type;
David S. Miller5ada5522011-02-17 15:29:00 -08002010 struct rtable *rth;
Julian Anastasovc92b9652012-10-08 11:41:19 +00002011 bool do_cache;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002012
Thomas Grafd0daebc32012-06-12 00:44:01 +00002013 in_dev = __in_dev_get_rcu(dev_out);
2014 if (!in_dev)
David S. Miller5ada5522011-02-17 15:29:00 -08002015 return ERR_PTR(-EINVAL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002016
Thomas Grafd0daebc32012-06-12 00:44:01 +00002017 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
2018 if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
2019 return ERR_PTR(-EINVAL);
2020
David S. Miller68a5e3d2011-03-11 20:07:33 -05002021 if (ipv4_is_lbcast(fl4->daddr))
David S. Miller982721f2011-02-16 21:44:24 -08002022 type = RTN_BROADCAST;
David S. Miller68a5e3d2011-03-11 20:07:33 -05002023 else if (ipv4_is_multicast(fl4->daddr))
David S. Miller982721f2011-02-16 21:44:24 -08002024 type = RTN_MULTICAST;
David S. Miller68a5e3d2011-03-11 20:07:33 -05002025 else if (ipv4_is_zeronet(fl4->daddr))
David S. Miller5ada5522011-02-17 15:29:00 -08002026 return ERR_PTR(-EINVAL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002027
2028 if (dev_out->flags & IFF_LOOPBACK)
2029 flags |= RTCF_LOCAL;
2030
Julian Anastasov63617422012-11-22 23:04:14 +02002031 do_cache = true;
David S. Miller982721f2011-02-16 21:44:24 -08002032 if (type == RTN_BROADCAST) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002033 flags |= RTCF_BROADCAST | RTCF_LOCAL;
David S. Miller982721f2011-02-16 21:44:24 -08002034 fi = NULL;
2035 } else if (type == RTN_MULTICAST) {
Eric Dumazetdd28d1a2010-09-29 11:53:50 +00002036 flags |= RTCF_MULTICAST | RTCF_LOCAL;
David S. Miller813b3b52011-04-28 14:48:42 -07002037 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
2038 fl4->flowi4_proto))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002039 flags &= ~RTCF_LOCAL;
Julian Anastasov63617422012-11-22 23:04:14 +02002040 else
2041 do_cache = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002042 /* If multicast route do not exist use
Eric Dumazetdd28d1a2010-09-29 11:53:50 +00002043 * default one, but do not gateway in this case.
2044 * Yes, it is hack.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002045 */
David S. Miller982721f2011-02-16 21:44:24 -08002046 if (fi && res->prefixlen < 4)
2047 fi = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002048 }
2049
David S. Millerf2bb4be2012-07-17 12:20:47 -07002050 fnhe = NULL;
Julian Anastasov63617422012-11-22 23:04:14 +02002051 do_cache &= fi != NULL;
2052 if (do_cache) {
David S. Millerc5038a82012-07-31 15:02:02 -07002053 struct rtable __rcu **prth;
Julian Anastasovc92b9652012-10-08 11:41:19 +00002054 struct fib_nh *nh = &FIB_RES_NH(*res);
Eric Dumazetd26b3a72012-07-31 05:45:30 +00002055
Julian Anastasovc92b9652012-10-08 11:41:19 +00002056 fnhe = find_exception(nh, fl4->daddr);
Xin Longdeed49d2016-02-18 21:21:19 +08002057 if (fnhe) {
Timo Teräs2ffae992013-06-27 10:27:05 +03002058 prth = &fnhe->fnhe_rth_output;
Xin Longdeed49d2016-02-18 21:21:19 +08002059 rth = rcu_dereference(*prth);
2060 if (rth && rth->dst.expires &&
2061 time_after(jiffies, rth->dst.expires)) {
2062 ip_del_fnhe(nh, fl4->daddr);
2063 fnhe = NULL;
2064 } else {
2065 goto rt_cache;
Julian Anastasovc92b9652012-10-08 11:41:19 +00002066 }
Julian Anastasovc92b9652012-10-08 11:41:19 +00002067 }
Xin Longdeed49d2016-02-18 21:21:19 +08002068
2069 if (unlikely(fl4->flowi4_flags &
2070 FLOWI_FLAG_KNOWN_NH &&
2071 !(nh->nh_gw &&
2072 nh->nh_scope == RT_SCOPE_LINK))) {
2073 do_cache = false;
2074 goto add;
2075 }
2076 prth = raw_cpu_ptr(nh->nh_pcpu_rth_output);
David S. Millerc5038a82012-07-31 15:02:02 -07002077 rth = rcu_dereference(*prth);
Xin Longdeed49d2016-02-18 21:21:19 +08002078
2079rt_cache:
David S. Millerc5038a82012-07-31 15:02:02 -07002080 if (rt_cache_valid(rth)) {
2081 dst_hold(&rth->dst);
2082 return rth;
David S. Millerf2bb4be2012-07-17 12:20:47 -07002083 }
2084 }
Julian Anastasovc92b9652012-10-08 11:41:19 +00002085
2086add:
David Ahernd08c4f32015-09-02 13:58:34 -07002087 rth = rt_dst_alloc(dev_out, flags, type,
David S. Miller5c1e6aa2011-04-28 14:13:38 -07002088 IN_DEV_CONF_GET(in_dev, NOPOLICY),
David S. Millerf2bb4be2012-07-17 12:20:47 -07002089 IN_DEV_CONF_GET(in_dev, NOXFRM),
Julian Anastasovc92b9652012-10-08 11:41:19 +00002090 do_cache);
Dimitris Michailidis8391d072010-10-07 14:48:38 +00002091 if (!rth)
David S. Miller5ada5522011-02-17 15:29:00 -08002092 return ERR_PTR(-ENOBUFS);
Dimitris Michailidis8391d072010-10-07 14:48:38 +00002093
David S. Miller13378ca2012-07-23 13:57:45 -07002094 rth->rt_iif = orig_oif ? : 0;
David Ahernb7503e02015-09-02 13:58:35 -07002095 if (res->table)
2096 rth->rt_table_id = res->table->tb_id;
2097
Linus Torvalds1da177e2005-04-16 15:20:36 -07002098 RT_CACHE_STAT_INC(out_slow_tot);
2099
Linus Torvalds1da177e2005-04-16 15:20:36 -07002100 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09002101 if (flags & RTCF_LOCAL &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07002102 !(dev_out->flags & IFF_LOOPBACK)) {
Changli Gaod8d1f302010-06-10 23:31:35 -07002103 rth->dst.output = ip_mc_output;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002104 RT_CACHE_STAT_INC(out_slow_mc);
2105 }
2106#ifdef CONFIG_IP_MROUTE
David S. Miller982721f2011-02-16 21:44:24 -08002107 if (type == RTN_MULTICAST) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002108 if (IN_DEV_MFORWARD(in_dev) &&
David S. Miller813b3b52011-04-28 14:48:42 -07002109 !ipv4_is_local_multicast(fl4->daddr)) {
Changli Gaod8d1f302010-06-10 23:31:35 -07002110 rth->dst.input = ip_mr_input;
2111 rth->dst.output = ip_mc_output;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002112 }
2113 }
2114#endif
2115 }
2116
David S. Millerf2bb4be2012-07-17 12:20:47 -07002117 rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0);
Jiri Benc61adedf2015-08-20 13:56:25 +02002118 if (lwtunnel_output_redirect(rth->dst.lwtstate))
Robert Shearman0335f5b2015-08-03 17:39:21 +01002119 rth->dst.output = lwtunnel_output;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002120
David S. Miller5ada5522011-02-17 15:29:00 -08002121 return rth;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122}
2123
Linus Torvalds1da177e2005-04-16 15:20:36 -07002124/*
2125 * Major route resolver routine.
2126 */
2127
Peter Nørlund79a13152015-09-30 10:12:22 +02002128struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
2129 int mp_hash)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002130{
Linus Torvalds1da177e2005-04-16 15:20:36 -07002131 struct net_device *dev_out = NULL;
Julian Anastasovf61759e2011-12-02 11:39:42 +00002132 __u8 tos = RT_FL_TOS(fl4);
David S. Miller813b3b52011-04-28 14:48:42 -07002133 unsigned int flags = 0;
2134 struct fib_result res;
David S. Miller5ada5522011-02-17 15:29:00 -08002135 struct rtable *rth;
David S. Miller813b3b52011-04-28 14:48:42 -07002136 int orig_oif;
Nikola ForrĂ³0315e382015-09-17 16:01:32 +02002137 int err = -ENETUNREACH;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002138
David S. Miller85b91b02012-07-13 08:21:29 -07002139 res.tclassid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002140 res.fi = NULL;
David S. Miller8b96d222012-06-11 02:01:56 -07002141 res.table = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002142
David S. Miller813b3b52011-04-28 14:48:42 -07002143 orig_oif = fl4->flowi4_oif;
2144
Pavel Emelyanov1fb94892012-08-08 21:53:36 +00002145 fl4->flowi4_iif = LOOPBACK_IFINDEX;
David S. Miller813b3b52011-04-28 14:48:42 -07002146 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
2147 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
2148 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
David S. Miller44713b62011-03-04 21:24:47 -08002149
David S. Miller010c2702011-02-17 15:37:09 -08002150 rcu_read_lock();
David S. Miller813b3b52011-04-28 14:48:42 -07002151 if (fl4->saddr) {
David S. Millerb23dd4f2011-03-02 14:31:35 -08002152 rth = ERR_PTR(-EINVAL);
David S. Miller813b3b52011-04-28 14:48:42 -07002153 if (ipv4_is_multicast(fl4->saddr) ||
2154 ipv4_is_lbcast(fl4->saddr) ||
2155 ipv4_is_zeronet(fl4->saddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002156 goto out;
2157
Linus Torvalds1da177e2005-04-16 15:20:36 -07002158 /* I removed check for oif == dev_out->oif here.
2159 It was wrong for two reasons:
Denis V. Lunev1ab35272008-01-22 22:04:30 -08002160 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
2161 is assigned to multiple interfaces.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002162 2. Moreover, we are allowed to send packets with saddr
2163 of another iface. --ANK
2164 */
2165
David S. Miller813b3b52011-04-28 14:48:42 -07002166 if (fl4->flowi4_oif == 0 &&
2167 (ipv4_is_multicast(fl4->daddr) ||
2168 ipv4_is_lbcast(fl4->daddr))) {
Julian Anastasova210d012008-10-01 07:28:28 -07002169 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
David S. Miller813b3b52011-04-28 14:48:42 -07002170 dev_out = __ip_dev_find(net, fl4->saddr, false);
Ian Morris51456b22015-04-03 09:17:26 +01002171 if (!dev_out)
Julian Anastasova210d012008-10-01 07:28:28 -07002172 goto out;
2173
Linus Torvalds1da177e2005-04-16 15:20:36 -07002174 /* Special hack: user can direct multicasts
2175 and limited broadcast via necessary interface
2176 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
2177 This hack is not just for fun, it allows
2178 vic,vat and friends to work.
2179 They bind socket to loopback, set ttl to zero
2180 and expect that it will work.
2181 From the viewpoint of routing cache they are broken,
2182 because we are not allowed to build multicast path
2183 with loopback source addr (look, routing cache
2184 cannot know, that ttl is zero, so that packet
2185 will not leave this host and route is valid).
2186 Luckily, this hack is good workaround.
2187 */
2188
David S. Miller813b3b52011-04-28 14:48:42 -07002189 fl4->flowi4_oif = dev_out->ifindex;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002190 goto make_route;
2191 }
Julian Anastasova210d012008-10-01 07:28:28 -07002192
David S. Miller813b3b52011-04-28 14:48:42 -07002193 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
Julian Anastasova210d012008-10-01 07:28:28 -07002194 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
David S. Miller813b3b52011-04-28 14:48:42 -07002195 if (!__ip_dev_find(net, fl4->saddr, false))
Julian Anastasova210d012008-10-01 07:28:28 -07002196 goto out;
Julian Anastasova210d012008-10-01 07:28:28 -07002197 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002198 }
2199
2200
David S. Miller813b3b52011-04-28 14:48:42 -07002201 if (fl4->flowi4_oif) {
2202 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
David S. Millerb23dd4f2011-03-02 14:31:35 -08002203 rth = ERR_PTR(-ENODEV);
Ian Morris51456b22015-04-03 09:17:26 +01002204 if (!dev_out)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002205 goto out;
Herbert Xue5ed6392005-10-03 14:35:55 -07002206
2207 /* RACE: Check return value of inet_select_addr instead. */
Eric Dumazetfc75fc82010-12-22 04:39:39 +00002208 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
David S. Millerb23dd4f2011-03-02 14:31:35 -08002209 rth = ERR_PTR(-ENETUNREACH);
Eric Dumazetfc75fc82010-12-22 04:39:39 +00002210 goto out;
2211 }
David S. Miller813b3b52011-04-28 14:48:42 -07002212 if (ipv4_is_local_multicast(fl4->daddr) ||
Andrew Lunn6a211652015-05-01 16:39:54 +02002213 ipv4_is_lbcast(fl4->daddr) ||
2214 fl4->flowi4_proto == IPPROTO_IGMP) {
David S. Miller813b3b52011-04-28 14:48:42 -07002215 if (!fl4->saddr)
2216 fl4->saddr = inet_select_addr(dev_out, 0,
2217 RT_SCOPE_LINK);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002218 goto make_route;
2219 }
Jiri Benc0a7e2262013-10-04 17:04:48 +02002220 if (!fl4->saddr) {
David S. Miller813b3b52011-04-28 14:48:42 -07002221 if (ipv4_is_multicast(fl4->daddr))
2222 fl4->saddr = inet_select_addr(dev_out, 0,
2223 fl4->flowi4_scope);
2224 else if (!fl4->daddr)
2225 fl4->saddr = inet_select_addr(dev_out, 0,
2226 RT_SCOPE_HOST);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002227 }
David Ahern8e1ed702015-09-29 20:07:15 -07002228
2229 rth = l3mdev_get_rtable(dev_out, fl4);
2230 if (rth)
David Ahern613d09b2015-08-13 14:59:02 -06002231 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002232 }
2233
David S. Miller813b3b52011-04-28 14:48:42 -07002234 if (!fl4->daddr) {
2235 fl4->daddr = fl4->saddr;
2236 if (!fl4->daddr)
2237 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
Denis V. Lunevb40afd02008-01-22 22:06:19 -08002238 dev_out = net->loopback_dev;
Pavel Emelyanov1fb94892012-08-08 21:53:36 +00002239 fl4->flowi4_oif = LOOPBACK_IFINDEX;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002240 res.type = RTN_LOCAL;
2241 flags |= RTCF_LOCAL;
2242 goto make_route;
2243 }
2244
Nikola ForrĂ³0315e382015-09-17 16:01:32 +02002245 err = fib_lookup(net, fl4, &res, 0);
2246 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002247 res.fi = NULL;
David S. Miller8b96d222012-06-11 02:01:56 -07002248 res.table = NULL;
David Ahern28335a72015-10-07 08:40:13 -07002249 if (fl4->flowi4_oif &&
2250 !netif_index_is_l3_master(net, fl4->flowi4_oif)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002251 /* Apparently, routing tables are wrong. Assume,
2252 that the destination is on link.
2253
2254 WHY? DW.
2255 Because we are allowed to send to iface
2256 even if it has NO routes and NO assigned
2257 addresses. When oif is specified, routing
2258 tables are looked up with only one purpose:
2259 to catch if destination is gatewayed, rather than
2260 direct. Moreover, if MSG_DONTROUTE is set,
2261 we send packet, ignoring both routing tables
2262 and ifaddr state. --ANK
2263
2264
2265 We could make it even if oif is unknown,
2266 likely IPv6, but we do not.
2267 */
2268
David S. Miller813b3b52011-04-28 14:48:42 -07002269 if (fl4->saddr == 0)
2270 fl4->saddr = inet_select_addr(dev_out, 0,
2271 RT_SCOPE_LINK);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002272 res.type = RTN_UNICAST;
2273 goto make_route;
2274 }
Nikola ForrĂ³0315e382015-09-17 16:01:32 +02002275 rth = ERR_PTR(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002276 goto out;
2277 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002278
2279 if (res.type == RTN_LOCAL) {
David S. Miller813b3b52011-04-28 14:48:42 -07002280 if (!fl4->saddr) {
Joel Sing9fc3bbb2011-01-03 20:24:20 +00002281 if (res.fi->fib_prefsrc)
David S. Miller813b3b52011-04-28 14:48:42 -07002282 fl4->saddr = res.fi->fib_prefsrc;
Joel Sing9fc3bbb2011-01-03 20:24:20 +00002283 else
David S. Miller813b3b52011-04-28 14:48:42 -07002284 fl4->saddr = fl4->daddr;
Joel Sing9fc3bbb2011-01-03 20:24:20 +00002285 }
Denis V. Lunevb40afd02008-01-22 22:06:19 -08002286 dev_out = net->loopback_dev;
David S. Miller813b3b52011-04-28 14:48:42 -07002287 fl4->flowi4_oif = dev_out->ifindex;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002288 flags |= RTCF_LOCAL;
2289 goto make_route;
2290 }
2291
David Ahern3ce58d82015-10-05 08:51:25 -07002292 fib_select_path(net, &res, fl4, mp_hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002293
Linus Torvalds1da177e2005-04-16 15:20:36 -07002294 dev_out = FIB_RES_DEV(res);
David S. Miller813b3b52011-04-28 14:48:42 -07002295 fl4->flowi4_oif = dev_out->ifindex;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002296
2297
2298make_route:
David Miller1a00fee2012-07-01 02:02:56 +00002299 rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002300
David S. Miller010c2702011-02-17 15:37:09 -08002301out:
2302 rcu_read_unlock();
David S. Millerb23dd4f2011-03-02 14:31:35 -08002303 return rth;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002304}
Peter Nørlund79a13152015-09-30 10:12:22 +02002305EXPORT_SYMBOL_GPL(__ip_route_output_key_hash);
Arnaldo Carvalho de Melod8c97a92005-08-09 20:12:12 -07002306
Jianzhao Wangae2688d2010-09-08 14:35:43 -07002307static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2308{
2309 return NULL;
2310}
2311
Steffen Klassertebb762f2011-11-23 02:12:51 +00002312static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
Roland Dreierec831ea2011-01-31 13:16:00 -08002313{
Steffen Klassert618f9bc2011-11-23 02:13:31 +00002314 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2315
2316 return mtu ? : dst->dev->mtu;
Roland Dreierec831ea2011-01-31 13:16:00 -08002317}
2318
David S. Miller6700c272012-07-17 03:29:28 -07002319static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
2320 struct sk_buff *skb, u32 mtu)
David S. Miller14e50e52007-05-24 18:17:54 -07002321{
2322}
2323
David S. Miller6700c272012-07-17 03:29:28 -07002324static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
2325 struct sk_buff *skb)
David S. Millerb587ee32012-07-12 00:39:24 -07002326{
2327}
2328
Held Bernhard0972ddb2011-04-24 22:07:32 +00002329static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
2330 unsigned long old)
2331{
2332 return NULL;
2333}
2334
David S. Miller14e50e52007-05-24 18:17:54 -07002335static struct dst_ops ipv4_dst_blackhole_ops = {
2336 .family = AF_INET,
Jianzhao Wangae2688d2010-09-08 14:35:43 -07002337 .check = ipv4_blackhole_dst_check,
Steffen Klassertebb762f2011-11-23 02:12:51 +00002338 .mtu = ipv4_blackhole_mtu,
Eric Dumazet214f45c2011-02-18 11:39:01 -08002339 .default_advmss = ipv4_default_advmss,
David S. Miller14e50e52007-05-24 18:17:54 -07002340 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
David S. Millerb587ee32012-07-12 00:39:24 -07002341 .redirect = ipv4_rt_blackhole_redirect,
Held Bernhard0972ddb2011-04-24 22:07:32 +00002342 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
David S. Millerd3aaeb32011-07-18 00:40:17 -07002343 .neigh_lookup = ipv4_neigh_lookup,
David S. Miller14e50e52007-05-24 18:17:54 -07002344};
2345
David S. Miller2774c132011-03-01 14:59:04 -08002346struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
David S. Miller14e50e52007-05-24 18:17:54 -07002347{
David S. Miller2774c132011-03-01 14:59:04 -08002348 struct rtable *ort = (struct rtable *) dst_orig;
David S. Millerf5b0a872012-07-19 12:31:33 -07002349 struct rtable *rt;
David S. Miller14e50e52007-05-24 18:17:54 -07002350
David S. Millerf5b0a872012-07-19 12:31:33 -07002351 rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
David S. Miller14e50e52007-05-24 18:17:54 -07002352 if (rt) {
Changli Gaod8d1f302010-06-10 23:31:35 -07002353 struct dst_entry *new = &rt->dst;
David S. Miller14e50e52007-05-24 18:17:54 -07002354
David S. Miller14e50e52007-05-24 18:17:54 -07002355 new->__use = 1;
Herbert Xu352e5122007-11-13 21:34:06 -08002356 new->input = dst_discard;
Eric W. Biedermanede20592015-10-07 16:48:47 -05002357 new->output = dst_discard_out;
David S. Miller14e50e52007-05-24 18:17:54 -07002358
Changli Gaod8d1f302010-06-10 23:31:35 -07002359 new->dev = ort->dst.dev;
David S. Miller14e50e52007-05-24 18:17:54 -07002360 if (new->dev)
2361 dev_hold(new->dev);
2362
David S. Miller9917e1e82012-07-17 14:44:26 -07002363 rt->rt_is_input = ort->rt_is_input;
David S. Miller5e2b61f2011-03-04 21:47:09 -08002364 rt->rt_iif = ort->rt_iif;
David S. Miller59436342012-07-10 06:58:42 -07002365 rt->rt_pmtu = ort->rt_pmtu;
David S. Miller14e50e52007-05-24 18:17:54 -07002366
fan.duca4c3fc2013-07-30 08:33:53 +08002367 rt->rt_genid = rt_genid_ipv4(net);
David S. Miller14e50e52007-05-24 18:17:54 -07002368 rt->rt_flags = ort->rt_flags;
2369 rt->rt_type = ort->rt_type;
David S. Miller14e50e52007-05-24 18:17:54 -07002370 rt->rt_gateway = ort->rt_gateway;
Julian Anastasov155e8332012-10-08 11:41:18 +00002371 rt->rt_uses_gateway = ort->rt_uses_gateway;
David S. Miller14e50e52007-05-24 18:17:54 -07002372
David S. Millercaacf052012-07-31 15:06:50 -07002373 INIT_LIST_HEAD(&rt->rt_uncached);
David S. Miller14e50e52007-05-24 18:17:54 -07002374 dst_free(new);
2375 }
2376
David S. Miller2774c132011-03-01 14:59:04 -08002377 dst_release(dst_orig);
2378
2379 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
David S. Miller14e50e52007-05-24 18:17:54 -07002380}
2381
David S. Miller9d6ec932011-03-12 01:12:47 -05002382struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
Eric Dumazet6f9c9612015-09-25 07:39:10 -07002383 const struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002384{
David S. Miller9d6ec932011-03-12 01:12:47 -05002385 struct rtable *rt = __ip_route_output_key(net, flp4);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002386
David S. Millerb23dd4f2011-03-02 14:31:35 -08002387 if (IS_ERR(rt))
2388 return rt;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002389
David S. Miller56157872011-05-02 14:37:45 -07002390 if (flp4->flowi4_proto)
Steffen Klassertf92ee612014-09-16 10:08:40 +02002391 rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst,
2392 flowi4_to_flowi(flp4),
2393 sk, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002394
David S. Millerb23dd4f2011-03-02 14:31:35 -08002395 return rt;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002396}
Arnaldo Carvalho de Melod8c97a92005-08-09 20:12:12 -07002397EXPORT_SYMBOL_GPL(ip_route_output_flow);
2398
David Ahernc36ba662015-09-02 13:58:36 -07002399static int rt_fill_info(struct net *net, __be32 dst, __be32 src, u32 table_id,
Eric W. Biederman15e47302012-09-07 20:12:54 +00002400 struct flowi4 *fl4, struct sk_buff *skb, u32 portid,
David S. Millerf1ce3062012-07-12 10:10:17 -07002401 u32 seq, int event, int nowait, unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002402{
Eric Dumazet511c3f92009-06-02 05:14:27 +00002403 struct rtable *rt = skb_rtable(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002404 struct rtmsg *r;
Thomas Grafbe403ea2006-08-17 18:15:17 -07002405 struct nlmsghdr *nlh;
Steffen Klassert2bc8ca42011-10-11 01:12:02 +00002406 unsigned long expires = 0;
David S. Millerf1850712012-07-10 07:26:01 -07002407 u32 error;
Julian Anastasov521f5492012-07-20 12:02:08 +03002408 u32 metrics[RTAX_MAX];
Thomas Grafbe403ea2006-08-17 18:15:17 -07002409
Eric W. Biederman15e47302012-09-07 20:12:54 +00002410 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
Ian Morris51456b22015-04-03 09:17:26 +01002411 if (!nlh)
Patrick McHardy26932562007-01-31 23:16:40 -08002412 return -EMSGSIZE;
Thomas Grafbe403ea2006-08-17 18:15:17 -07002413
2414 r = nlmsg_data(nlh);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002415 r->rtm_family = AF_INET;
2416 r->rtm_dst_len = 32;
2417 r->rtm_src_len = 0;
David Millerd6c0a4f2012-07-01 02:02:59 +00002418 r->rtm_tos = fl4->flowi4_tos;
David Ahernc36ba662015-09-02 13:58:36 -07002419 r->rtm_table = table_id;
2420 if (nla_put_u32(skb, RTA_TABLE, table_id))
David S. Millerf3756b72012-04-01 20:39:02 -04002421 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002422 r->rtm_type = rt->rt_type;
2423 r->rtm_scope = RT_SCOPE_UNIVERSE;
2424 r->rtm_protocol = RTPROT_UNSPEC;
2425 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2426 if (rt->rt_flags & RTCF_NOTIFY)
2427 r->rtm_flags |= RTM_F_NOTIFY;
Hannes Frederic Sowadf4d9252015-01-23 12:01:26 +01002428 if (IPCB(skb)->flags & IPSKB_DOREDIRECT)
2429 r->rtm_flags |= RTCF_DOREDIRECT;
Thomas Grafbe403ea2006-08-17 18:15:17 -07002430
Jiri Benc930345e2015-03-29 16:59:25 +02002431 if (nla_put_in_addr(skb, RTA_DST, dst))
David S. Millerf3756b72012-04-01 20:39:02 -04002432 goto nla_put_failure;
David Miller1a00fee2012-07-01 02:02:56 +00002433 if (src) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002434 r->rtm_src_len = 32;
Jiri Benc930345e2015-03-29 16:59:25 +02002435 if (nla_put_in_addr(skb, RTA_SRC, src))
David S. Millerf3756b72012-04-01 20:39:02 -04002436 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002437 }
David S. Millerf3756b72012-04-01 20:39:02 -04002438 if (rt->dst.dev &&
2439 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2440 goto nla_put_failure;
Patrick McHardyc7066f72011-01-14 13:36:42 +01002441#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Millerf3756b72012-04-01 20:39:02 -04002442 if (rt->dst.tclassid &&
2443 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2444 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002445#endif
David S. Miller41347dc2012-06-28 04:05:27 -07002446 if (!rt_is_input_route(rt) &&
David Millerd6c0a4f2012-07-01 02:02:59 +00002447 fl4->saddr != src) {
Jiri Benc930345e2015-03-29 16:59:25 +02002448 if (nla_put_in_addr(skb, RTA_PREFSRC, fl4->saddr))
David S. Millerf3756b72012-04-01 20:39:02 -04002449 goto nla_put_failure;
2450 }
Julian Anastasov155e8332012-10-08 11:41:18 +00002451 if (rt->rt_uses_gateway &&
Jiri Benc930345e2015-03-29 16:59:25 +02002452 nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gateway))
David S. Millerf3756b72012-04-01 20:39:02 -04002453 goto nla_put_failure;
Thomas Grafbe403ea2006-08-17 18:15:17 -07002454
Steffen Klassertee9a8f72012-10-08 00:56:54 +00002455 expires = rt->dst.expires;
2456 if (expires) {
2457 unsigned long now = jiffies;
2458
2459 if (time_before(now, expires))
2460 expires -= now;
2461 else
2462 expires = 0;
2463 }
2464
Julian Anastasov521f5492012-07-20 12:02:08 +03002465 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
Steffen Klassertee9a8f72012-10-08 00:56:54 +00002466 if (rt->rt_pmtu && expires)
Julian Anastasov521f5492012-07-20 12:02:08 +03002467 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2468 if (rtnetlink_put_metrics(skb, metrics) < 0)
Thomas Grafbe403ea2006-08-17 18:15:17 -07002469 goto nla_put_failure;
2470
David Millerb4869882012-07-01 02:03:01 +00002471 if (fl4->flowi4_mark &&
stephen hemminger68aaed52012-10-10 08:27:25 +00002472 nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark))
David S. Millerf3756b72012-04-01 20:39:02 -04002473 goto nla_put_failure;
Eric Dumazet963bfee2010-07-20 22:03:14 +00002474
Changli Gaod8d1f302010-06-10 23:31:35 -07002475 error = rt->dst.error;
Thomas Grafbe403ea2006-08-17 18:15:17 -07002476
David S. Millerc7537962010-11-11 17:07:48 -08002477 if (rt_is_input_route(rt)) {
Nicolas Dichtel8caaf7b2012-12-04 01:03:07 +00002478#ifdef CONFIG_IP_MROUTE
2479 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2480 IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
2481 int err = ipmr_get_route(net, skb,
2482 fl4->saddr, fl4->daddr,
2483 r, nowait);
2484 if (err <= 0) {
2485 if (!nowait) {
2486 if (err == 0)
2487 return 0;
2488 goto nla_put_failure;
2489 } else {
2490 if (err == -EMSGSIZE)
2491 goto nla_put_failure;
2492 error = err;
2493 }
2494 }
2495 } else
2496#endif
Julian Anastasov91146152014-04-13 18:08:02 +03002497 if (nla_put_u32(skb, RTA_IIF, skb->dev->ifindex))
Nicolas Dichtel8caaf7b2012-12-04 01:03:07 +00002498 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002499 }
2500
David S. Millerf1850712012-07-10 07:26:01 -07002501 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
Thomas Grafe3703b32006-11-27 09:27:07 -08002502 goto nla_put_failure;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002503
Johannes Berg053c0952015-01-16 22:09:00 +01002504 nlmsg_end(skb, nlh);
2505 return 0;
Thomas Grafbe403ea2006-08-17 18:15:17 -07002506
2507nla_put_failure:
Patrick McHardy26932562007-01-31 23:16:40 -08002508 nlmsg_cancel(skb, nlh);
2509 return -EMSGSIZE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002510}
2511
Thomas Graf661d2962013-03-21 07:45:29 +00002512static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002513{
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +09002514 struct net *net = sock_net(in_skb->sk);
Thomas Grafd889ce32006-08-17 18:15:44 -07002515 struct rtmsg *rtm;
2516 struct nlattr *tb[RTA_MAX+1];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002517 struct rtable *rt = NULL;
David Millerd6c0a4f2012-07-01 02:02:59 +00002518 struct flowi4 fl4;
Al Viro9e12bb22006-09-26 21:25:20 -07002519 __be32 dst = 0;
2520 __be32 src = 0;
2521 u32 iif;
Thomas Grafd889ce32006-08-17 18:15:44 -07002522 int err;
Eric Dumazet963bfee2010-07-20 22:03:14 +00002523 int mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002524 struct sk_buff *skb;
David Ahernc36ba662015-09-02 13:58:36 -07002525 u32 table_id = RT_TABLE_MAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002526
Thomas Grafd889ce32006-08-17 18:15:44 -07002527 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2528 if (err < 0)
2529 goto errout;
2530
2531 rtm = nlmsg_data(nlh);
2532
Linus Torvalds1da177e2005-04-16 15:20:36 -07002533 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
Ian Morris51456b22015-04-03 09:17:26 +01002534 if (!skb) {
Thomas Grafd889ce32006-08-17 18:15:44 -07002535 err = -ENOBUFS;
2536 goto errout;
2537 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002538
2539 /* Reserve room for dummy headers, this skb can pass
2540 through good chunk of routing engine.
2541 */
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -07002542 skb_reset_mac_header(skb);
Arnaldo Carvalho de Meloc1d2bbe2007-04-10 20:45:18 -07002543 skb_reset_network_header(skb);
Stephen Hemmingerd2c962b2006-04-17 17:27:11 -07002544
2545 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -07002546 ip_hdr(skb)->protocol = IPPROTO_ICMP;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002547 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2548
Jiri Benc67b61f62015-03-29 16:59:26 +02002549 src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
2550 dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
Thomas Grafd889ce32006-08-17 18:15:44 -07002551 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
Eric Dumazet963bfee2010-07-20 22:03:14 +00002552 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002553
David Millerd6c0a4f2012-07-01 02:02:59 +00002554 memset(&fl4, 0, sizeof(fl4));
2555 fl4.daddr = dst;
2556 fl4.saddr = src;
2557 fl4.flowi4_tos = rtm->rtm_tos;
2558 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2559 fl4.flowi4_mark = mark;
2560
David Aherndeaa0a62015-10-05 10:49:04 -07002561 if (netif_index_is_l3_master(net, fl4.flowi4_oif))
2562 fl4.flowi4_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF;
2563
Linus Torvalds1da177e2005-04-16 15:20:36 -07002564 if (iif) {
Thomas Grafd889ce32006-08-17 18:15:44 -07002565 struct net_device *dev;
2566
Denis V. Lunev19375042008-02-28 20:52:04 -08002567 dev = __dev_get_by_index(net, iif);
Ian Morris51456b22015-04-03 09:17:26 +01002568 if (!dev) {
Thomas Grafd889ce32006-08-17 18:15:44 -07002569 err = -ENODEV;
2570 goto errout_free;
2571 }
2572
Linus Torvalds1da177e2005-04-16 15:20:36 -07002573 skb->protocol = htons(ETH_P_IP);
2574 skb->dev = dev;
Eric Dumazet963bfee2010-07-20 22:03:14 +00002575 skb->mark = mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002576 local_bh_disable();
2577 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2578 local_bh_enable();
Thomas Grafd889ce32006-08-17 18:15:44 -07002579
Eric Dumazet511c3f92009-06-02 05:14:27 +00002580 rt = skb_rtable(skb);
Changli Gaod8d1f302010-06-10 23:31:35 -07002581 if (err == 0 && rt->dst.error)
2582 err = -rt->dst.error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002583 } else {
David S. Miller9d6ec932011-03-12 01:12:47 -05002584 rt = ip_route_output_key(net, &fl4);
David S. Millerb23dd4f2011-03-02 14:31:35 -08002585
2586 err = 0;
2587 if (IS_ERR(rt))
2588 err = PTR_ERR(rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002589 }
Thomas Grafd889ce32006-08-17 18:15:44 -07002590
Linus Torvalds1da177e2005-04-16 15:20:36 -07002591 if (err)
Thomas Grafd889ce32006-08-17 18:15:44 -07002592 goto errout_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002593
Changli Gaod8d1f302010-06-10 23:31:35 -07002594 skb_dst_set(skb, &rt->dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002595 if (rtm->rtm_flags & RTM_F_NOTIFY)
2596 rt->rt_flags |= RTCF_NOTIFY;
2597
David Ahernc36ba662015-09-02 13:58:36 -07002598 if (rtm->rtm_flags & RTM_F_LOOKUP_TABLE)
2599 table_id = rt->rt_table_id;
2600
2601 err = rt_fill_info(net, dst, src, table_id, &fl4, skb,
Eric W. Biederman15e47302012-09-07 20:12:54 +00002602 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
Denis V. Lunev19375042008-02-28 20:52:04 -08002603 RTM_NEWROUTE, 0, 0);
David S. Miller7b46a642015-01-18 23:36:08 -05002604 if (err < 0)
Thomas Grafd889ce32006-08-17 18:15:44 -07002605 goto errout_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002606
Eric W. Biederman15e47302012-09-07 20:12:54 +00002607 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
Thomas Grafd889ce32006-08-17 18:15:44 -07002608errout:
Thomas Graf2942e902006-08-15 00:30:25 -07002609 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002610
Thomas Grafd889ce32006-08-17 18:15:44 -07002611errout_free:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002612 kfree_skb(skb);
Thomas Grafd889ce32006-08-17 18:15:44 -07002613 goto errout;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002614}
2615
Linus Torvalds1da177e2005-04-16 15:20:36 -07002616void ip_rt_multicast_event(struct in_device *in_dev)
2617{
Nicolas Dichtel4ccfe6d2012-09-07 00:45:29 +00002618 rt_cache_flush(dev_net(in_dev->dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002619}
2620
2621#ifdef CONFIG_SYSCTL
Gao feng082c7ca2013-02-19 00:43:12 +00002622static int ip_rt_gc_interval __read_mostly = 60 * HZ;
2623static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
2624static int ip_rt_gc_elasticity __read_mostly = 8;
2625
Joe Perchesfe2c6332013-06-11 23:04:25 -07002626static int ipv4_sysctl_rtcache_flush(struct ctl_table *__ctl, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002627 void __user *buffer,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002628 size_t *lenp, loff_t *ppos)
2629{
Timo Teräs5aad1de2013-05-27 20:46:33 +00002630 struct net *net = (struct net *)__ctl->extra1;
2631
Linus Torvalds1da177e2005-04-16 15:20:36 -07002632 if (write) {
Timo Teräs5aad1de2013-05-27 20:46:33 +00002633 rt_cache_flush(net);
2634 fnhe_genid_bump(net);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002635 return 0;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09002636 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002637
2638 return -EINVAL;
2639}
2640
Joe Perchesfe2c6332013-06-11 23:04:25 -07002641static struct ctl_table ipv4_route_table[] = {
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09002642 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002643 .procname = "gc_thresh",
2644 .data = &ipv4_dst_ops.gc_thresh,
2645 .maxlen = sizeof(int),
2646 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002647 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002648 },
2649 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002650 .procname = "max_size",
2651 .data = &ip_rt_max_size,
2652 .maxlen = sizeof(int),
2653 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002654 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002655 },
2656 {
2657 /* Deprecated. Use gc_min_interval_ms */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09002658
Linus Torvalds1da177e2005-04-16 15:20:36 -07002659 .procname = "gc_min_interval",
2660 .data = &ip_rt_gc_min_interval,
2661 .maxlen = sizeof(int),
2662 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002663 .proc_handler = proc_dointvec_jiffies,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002664 },
2665 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002666 .procname = "gc_min_interval_ms",
2667 .data = &ip_rt_gc_min_interval,
2668 .maxlen = sizeof(int),
2669 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002670 .proc_handler = proc_dointvec_ms_jiffies,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002671 },
2672 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002673 .procname = "gc_timeout",
2674 .data = &ip_rt_gc_timeout,
2675 .maxlen = sizeof(int),
2676 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002677 .proc_handler = proc_dointvec_jiffies,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002678 },
2679 {
Eric Dumazet9f28a2f2011-12-21 15:47:16 -05002680 .procname = "gc_interval",
2681 .data = &ip_rt_gc_interval,
2682 .maxlen = sizeof(int),
2683 .mode = 0644,
2684 .proc_handler = proc_dointvec_jiffies,
2685 },
2686 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002687 .procname = "redirect_load",
2688 .data = &ip_rt_redirect_load,
2689 .maxlen = sizeof(int),
2690 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002691 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002692 },
2693 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002694 .procname = "redirect_number",
2695 .data = &ip_rt_redirect_number,
2696 .maxlen = sizeof(int),
2697 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002698 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002699 },
2700 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002701 .procname = "redirect_silence",
2702 .data = &ip_rt_redirect_silence,
2703 .maxlen = sizeof(int),
2704 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002705 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002706 },
2707 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002708 .procname = "error_cost",
2709 .data = &ip_rt_error_cost,
2710 .maxlen = sizeof(int),
2711 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002712 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002713 },
2714 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002715 .procname = "error_burst",
2716 .data = &ip_rt_error_burst,
2717 .maxlen = sizeof(int),
2718 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002719 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002720 },
2721 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002722 .procname = "gc_elasticity",
2723 .data = &ip_rt_gc_elasticity,
2724 .maxlen = sizeof(int),
2725 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002726 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002727 },
2728 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002729 .procname = "mtu_expires",
2730 .data = &ip_rt_mtu_expires,
2731 .maxlen = sizeof(int),
2732 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002733 .proc_handler = proc_dointvec_jiffies,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002734 },
2735 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002736 .procname = "min_pmtu",
2737 .data = &ip_rt_min_pmtu,
2738 .maxlen = sizeof(int),
2739 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002740 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002741 },
2742 {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002743 .procname = "min_adv_mss",
2744 .data = &ip_rt_min_advmss,
2745 .maxlen = sizeof(int),
2746 .mode = 0644,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002747 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002748 },
Eric W. Biedermanf8572d82009-11-05 13:32:03 -08002749 { }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002750};
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002751
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002752static struct ctl_table ipv4_route_flush_table[] = {
2753 {
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002754 .procname = "flush",
2755 .maxlen = sizeof(int),
2756 .mode = 0200,
Alexey Dobriyan6d9f2392008-11-03 18:21:05 -08002757 .proc_handler = ipv4_sysctl_rtcache_flush,
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002758 },
Eric W. Biedermanf8572d82009-11-05 13:32:03 -08002759 { },
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002760};
2761
2762static __net_init int sysctl_route_net_init(struct net *net)
2763{
2764 struct ctl_table *tbl;
2765
2766 tbl = ipv4_route_flush_table;
Octavian Purdila09ad9bc2009-11-25 15:14:13 -08002767 if (!net_eq(net, &init_net)) {
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002768 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
Ian Morris51456b22015-04-03 09:17:26 +01002769 if (!tbl)
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002770 goto err_dup;
Eric W. Biederman464dc802012-11-16 03:02:59 +00002771
2772 /* Don't export sysctls to unprivileged users */
2773 if (net->user_ns != &init_user_ns)
2774 tbl[0].procname = NULL;
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002775 }
2776 tbl[0].extra1 = net;
2777
Eric W. Biedermanec8f23c2012-04-19 13:44:49 +00002778 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
Ian Morris51456b22015-04-03 09:17:26 +01002779 if (!net->ipv4.route_hdr)
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002780 goto err_reg;
2781 return 0;
2782
2783err_reg:
2784 if (tbl != ipv4_route_flush_table)
2785 kfree(tbl);
2786err_dup:
2787 return -ENOMEM;
2788}
2789
2790static __net_exit void sysctl_route_net_exit(struct net *net)
2791{
2792 struct ctl_table *tbl;
2793
2794 tbl = net->ipv4.route_hdr->ctl_table_arg;
2795 unregister_net_sysctl_table(net->ipv4.route_hdr);
2796 BUG_ON(tbl == ipv4_route_flush_table);
2797 kfree(tbl);
2798}
2799
2800static __net_initdata struct pernet_operations sysctl_route_ops = {
2801 .init = sysctl_route_net_init,
2802 .exit = sysctl_route_net_exit,
2803};
Linus Torvalds1da177e2005-04-16 15:20:36 -07002804#endif
2805
Neil Horman3ee94372010-05-08 01:57:52 -07002806static __net_init int rt_genid_init(struct net *net)
Denis V. Lunev9f5e97e2008-07-05 19:02:59 -07002807{
fan.duca4c3fc2013-07-30 08:33:53 +08002808 atomic_set(&net->ipv4.rt_genid, 0);
Timo Teräs5aad1de2013-05-27 20:46:33 +00002809 atomic_set(&net->fnhe_genid, 0);
David S. Miller436c3b62011-03-24 17:42:21 -07002810 get_random_bytes(&net->ipv4.dev_addr_genid,
2811 sizeof(net->ipv4.dev_addr_genid));
Denis V. Lunev9f5e97e2008-07-05 19:02:59 -07002812 return 0;
2813}
2814
Neil Horman3ee94372010-05-08 01:57:52 -07002815static __net_initdata struct pernet_operations rt_genid_ops = {
2816 .init = rt_genid_init,
Denis V. Lunev9f5e97e2008-07-05 19:02:59 -07002817};
2818
David S. Millerc3426b42012-06-09 16:27:05 -07002819static int __net_init ipv4_inetpeer_init(struct net *net)
2820{
2821 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
2822
2823 if (!bp)
2824 return -ENOMEM;
2825 inet_peer_base_init(bp);
2826 net->ipv4.peers = bp;
2827 return 0;
2828}
2829
2830static void __net_exit ipv4_inetpeer_exit(struct net *net)
2831{
2832 struct inet_peer_base *bp = net->ipv4.peers;
2833
2834 net->ipv4.peers = NULL;
David S. Miller56a6b242012-06-09 16:32:41 -07002835 inetpeer_invalidate_tree(bp);
David S. Millerc3426b42012-06-09 16:27:05 -07002836 kfree(bp);
2837}
2838
2839static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
2840 .init = ipv4_inetpeer_init,
2841 .exit = ipv4_inetpeer_exit,
2842};
Denis V. Lunev9f5e97e2008-07-05 19:02:59 -07002843
Patrick McHardyc7066f72011-01-14 13:36:42 +01002844#ifdef CONFIG_IP_ROUTE_CLASSID
Tejun Heo7d720c32010-02-16 15:20:26 +00002845struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
Patrick McHardyc7066f72011-01-14 13:36:42 +01002846#endif /* CONFIG_IP_ROUTE_CLASSID */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002847
Linus Torvalds1da177e2005-04-16 15:20:36 -07002848int __init ip_rt_init(void)
2849{
Eric Dumazet424c4b72005-07-05 14:58:19 -07002850 int rc = 0;
Eric Dumazet5055c372015-01-14 15:17:06 -08002851 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002852
Eric Dumazet73f156a2014-06-02 05:26:03 -07002853 ip_idents = kmalloc(IP_IDENTS_SZ * sizeof(*ip_idents), GFP_KERNEL);
2854 if (!ip_idents)
2855 panic("IP: failed to allocate ip_idents\n");
2856
2857 prandom_bytes(ip_idents, IP_IDENTS_SZ * sizeof(*ip_idents));
2858
Eric Dumazet355b5902015-05-01 10:37:49 -07002859 ip_tstamps = kcalloc(IP_IDENTS_SZ, sizeof(*ip_tstamps), GFP_KERNEL);
2860 if (!ip_tstamps)
2861 panic("IP: failed to allocate ip_tstamps\n");
2862
Eric Dumazet5055c372015-01-14 15:17:06 -08002863 for_each_possible_cpu(cpu) {
2864 struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
2865
2866 INIT_LIST_HEAD(&ul->head);
2867 spin_lock_init(&ul->lock);
2868 }
Patrick McHardyc7066f72011-01-14 13:36:42 +01002869#ifdef CONFIG_IP_ROUTE_CLASSID
Ingo Molnar0dcec8c2009-02-25 14:07:33 +01002870 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002871 if (!ip_rt_acct)
2872 panic("IP: failed to allocate ip_rt_acct\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002873#endif
2874
Alexey Dobriyane5d679f332006-08-26 19:25:52 -07002875 ipv4_dst_ops.kmem_cachep =
2876 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
Paul Mundt20c2df82007-07-20 10:11:58 +09002877 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002878
David S. Miller14e50e52007-05-24 18:17:54 -07002879 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
2880
Eric Dumazetfc66f952010-10-08 06:37:34 +00002881 if (dst_entries_init(&ipv4_dst_ops) < 0)
2882 panic("IP: failed to allocate ipv4_dst_ops counter\n");
2883
2884 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
2885 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
2886
David S. Miller89aef892012-07-17 11:00:09 -07002887 ipv4_dst_ops.gc_thresh = ~0;
2888 ip_rt_max_size = INT_MAX;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002889
Linus Torvalds1da177e2005-04-16 15:20:36 -07002890 devinet_init();
2891 ip_fib_init();
2892
Denis V. Lunev73b38712008-02-28 20:51:18 -08002893 if (ip_rt_proc_init())
Joe Perches058bd4d2012-03-11 18:36:11 +00002894 pr_err("Unable to create route proc files\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002895#ifdef CONFIG_XFRM
2896 xfrm_init();
Steffen Klassert703fb942012-11-13 08:52:24 +01002897 xfrm4_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002898#endif
Greg Rosec7ac8672011-06-10 01:27:09 +00002899 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL);
Thomas Graf63f34442007-03-22 11:55:17 -07002900
Denis V. Lunev39a23e72008-07-05 19:02:33 -07002901#ifdef CONFIG_SYSCTL
2902 register_pernet_subsys(&sysctl_route_ops);
2903#endif
Neil Horman3ee94372010-05-08 01:57:52 -07002904 register_pernet_subsys(&rt_genid_ops);
David S. Millerc3426b42012-06-09 16:27:05 -07002905 register_pernet_subsys(&ipv4_inetpeer_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002906 return rc;
2907}
2908
Al Viroa1bc6eb2008-07-30 06:32:52 -04002909#ifdef CONFIG_SYSCTL
Al Viroeeb61f72008-07-27 08:59:33 +01002910/*
2911 * We really need to sanitize the damn ipv4 init order, then all
2912 * this nonsense will go away.
2913 */
2914void __init ip_static_sysctl_init(void)
2915{
Eric W. Biederman4e5ca782012-04-19 13:32:39 +00002916 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);
Al Viroeeb61f72008-07-27 08:59:33 +01002917}
Al Viroa1bc6eb2008-07-30 06:32:52 -04002918#endif