blob: 26aa65d1fce49dfeaa45cbc02046218b5bc70453 [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 * IPv4 Forwarding Information Base: policy rules.
7 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
Eric Dumazet6a31d2a2010-10-04 20:00:18 +00009 * Thomas Graf <tgraf@suug.ch>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 *
16 * Fixes:
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000017 * Rani Assaf : local_rule cannot be deleted
Linus Torvalds1da177e2005-04-16 15:20:36 -070018 * Marc Boucher : routing by fwmark
19 */
20
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/types.h>
22#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/netdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/netlink.h>
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070025#include <linux/inetdevice.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/init.h>
Robert Olsson7b204af2006-03-20 17:18:53 -080027#include <linux/list.h>
28#include <linux/rcupdate.h>
Paul Gortmakerbc3b2d72011-07-15 11:47:34 -040029#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <net/ip.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <net/route.h>
32#include <net/tcp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <net/ip_fib.h>
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070034#include <net/fib_rules.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000036struct fib4_rule {
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070037 struct fib_rule common;
38 u8 dst_len;
39 u8 src_len;
40 u8 tos;
Al Viro81f7bf62006-09-27 18:40:00 -070041 __be32 src;
42 __be32 srcmask;
43 __be32 dst;
44 __be32 dstmask;
Patrick McHardyc7066f72011-01-14 13:36:42 +010045#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070046 u32 tclassid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070047#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070048};
49
David S. Millerf4530fa2012-07-05 22:13:13 -070050int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070051{
52 struct fib_lookup_arg arg = {
53 .result = res,
Eric Dumazetebc0ffa2010-10-05 10:41:36 +000054 .flags = FIB_LOOKUP_NOREF,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070055 };
56 int err;
57
David S. Miller22bd5b92011-03-11 19:54:08 -050058 err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
David S. Miller85b91b02012-07-13 08:21:29 -070059#ifdef CONFIG_IP_ROUTE_CLASSID
60 if (arg.rule)
61 res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
62 else
63 res->tclassid = 0;
64#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 return err;
66}
David S. Millerf4530fa2012-07-05 22:13:13 -070067EXPORT_SYMBOL_GPL(__fib_lookup);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
Adrian Bunk8ce11e62006-08-07 21:50:48 -070069static int fib4_rule_action(struct fib_rule *rule, struct flowi *flp,
70 int flags, struct fib_lookup_arg *arg)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070071{
72 int err = -EAGAIN;
73 struct fib_table *tbl;
74
75 switch (rule->action) {
76 case FR_ACT_TO_TBL:
77 break;
78
79 case FR_ACT_UNREACHABLE:
80 err = -ENETUNREACH;
81 goto errout;
82
83 case FR_ACT_PROHIBIT:
84 err = -EACCES;
85 goto errout;
86
87 case FR_ACT_BLACKHOLE:
88 default:
89 err = -EINVAL;
90 goto errout;
91 }
92
Eric Dumazet6a31d2a2010-10-04 20:00:18 +000093 tbl = fib_get_table(rule->fr_net, rule->table);
94 if (!tbl)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070095 goto errout;
96
David S. Miller22bd5b92011-03-11 19:54:08 -050097 err = fib_table_lookup(tbl, &flp->u.ip4, (struct fib_result *) arg->result, arg->flags);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070098 if (err > 0)
99 err = -EAGAIN;
100errout:
101 return err;
102}
103
104
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700105static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
106{
107 struct fib4_rule *r = (struct fib4_rule *) rule;
David S. Miller9ade2282011-03-12 02:02:42 -0500108 struct flowi4 *fl4 = &fl->u.ip4;
109 __be32 daddr = fl4->daddr;
110 __be32 saddr = fl4->saddr;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700111
112 if (((saddr ^ r->src) & r->srcmask) ||
113 ((daddr ^ r->dst) & r->dstmask))
114 return 0;
115
David S. Miller9ade2282011-03-12 02:02:42 -0500116 if (r->tos && (r->tos != fl4->flowi4_tos))
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700117 return 0;
118
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700119 return 1;
120}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
Denis V. Lunev8ad49422008-01-10 03:24:11 -0800122static struct fib_table *fib_empty_table(struct net *net)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123{
Patrick McHardy2dfe55b2006-08-10 23:08:33 -0700124 u32 id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
126 for (id = 1; id <= RT_TABLE_MAX; id++)
Denis V. Lunev8ad49422008-01-10 03:24:11 -0800127 if (fib_get_table(net, id) == NULL)
128 return fib_new_table(net, id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 return NULL;
130}
131
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700132static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
Thomas Graf1f6c9552006-11-09 15:22:48 -0800133 FRA_GENERIC_POLICY,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700134 [FRA_FLOW] = { .type = NLA_U32 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135};
136
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700137static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
Rami Rosen8b3521e2009-05-11 05:52:49 +0000138 struct fib_rule_hdr *frh,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700139 struct nlattr **tb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140{
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900141 struct net *net = sock_net(skb->sk);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700142 int err = -EINVAL;
143 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
Thomas Grafe1701c62007-03-24 12:46:02 -0700145 if (frh->tos & ~IPTOS_TOS_MASK)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700146 goto errout;
147
148 if (rule->table == RT_TABLE_UNSPEC) {
149 if (rule->action == FR_ACT_TO_TBL) {
150 struct fib_table *table;
151
Denis V. Luneve4e49712008-01-10 03:27:51 -0800152 table = fib_empty_table(net);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700153 if (table == NULL) {
154 err = -ENOBUFS;
155 goto errout;
156 }
157
158 rule->table = table->tb_id;
159 }
160 }
161
Thomas Grafe1701c62007-03-24 12:46:02 -0700162 if (frh->src_len)
Al Viro45d60b92006-09-27 18:40:27 -0700163 rule4->src = nla_get_be32(tb[FRA_SRC]);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700164
Thomas Grafe1701c62007-03-24 12:46:02 -0700165 if (frh->dst_len)
Al Viro45d60b92006-09-27 18:40:27 -0700166 rule4->dst = nla_get_be32(tb[FRA_DST]);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700167
Patrick McHardyc7066f72011-01-14 13:36:42 +0100168#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700169 if (tb[FRA_FLOW]) {
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700170 rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700171 if (rule4->tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700172 net->ipv4.fib_num_tclassid_users++;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700173 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700176 rule4->src_len = frh->src_len;
177 rule4->srcmask = inet_make_mask(rule4->src_len);
178 rule4->dst_len = frh->dst_len;
179 rule4->dstmask = inet_make_mask(rule4->dst_len);
180 rule4->tos = frh->tos;
181
David S. Millerf4530fa2012-07-05 22:13:13 -0700182 net->ipv4.fib_has_custom_rules = true;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700183 err = 0;
184errout:
185 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186}
187
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700188static void fib4_rule_delete(struct fib_rule *rule)
189{
David S. Millerf4530fa2012-07-05 22:13:13 -0700190 struct net *net = rule->fr_net;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700191#ifdef CONFIG_IP_ROUTE_CLASSID
192 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
193
194 if (rule4->tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700195 net->ipv4.fib_num_tclassid_users--;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700196#endif
David S. Millerf4530fa2012-07-05 22:13:13 -0700197 net->ipv4.fib_has_custom_rules = true;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700198}
199
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700200static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
201 struct nlattr **tb)
Patrick McHardya5cdc032006-03-23 01:16:06 -0800202{
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700203 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
Patrick McHardya5cdc032006-03-23 01:16:06 -0800204
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700205 if (frh->src_len && (rule4->src_len != frh->src_len))
206 return 0;
207
208 if (frh->dst_len && (rule4->dst_len != frh->dst_len))
209 return 0;
210
211 if (frh->tos && (rule4->tos != frh->tos))
212 return 0;
213
Patrick McHardyc7066f72011-01-14 13:36:42 +0100214#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700215 if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
216 return 0;
217#endif
218
Thomas Grafe1701c62007-03-24 12:46:02 -0700219 if (frh->src_len && (rule4->src != nla_get_be32(tb[FRA_SRC])))
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700220 return 0;
221
Thomas Grafe1701c62007-03-24 12:46:02 -0700222 if (frh->dst_len && (rule4->dst != nla_get_be32(tb[FRA_DST])))
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700223 return 0;
224
225 return 1;
226}
227
228static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
Rami Rosen04af8cf2009-05-20 17:26:23 -0700229 struct fib_rule_hdr *frh)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700230{
231 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
232
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700233 frh->dst_len = rule4->dst_len;
234 frh->src_len = rule4->src_len;
235 frh->tos = rule4->tos;
236
David S. Millerf3756b72012-04-01 20:39:02 -0400237 if ((rule4->dst_len &&
238 nla_put_be32(skb, FRA_DST, rule4->dst)) ||
239 (rule4->src_len &&
240 nla_put_be32(skb, FRA_SRC, rule4->src)))
241 goto nla_put_failure;
Patrick McHardyc7066f72011-01-14 13:36:42 +0100242#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Millerf3756b72012-04-01 20:39:02 -0400243 if (rule4->tclassid &&
244 nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
245 goto nla_put_failure;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700246#endif
247 return 0;
248
249nla_put_failure:
250 return -ENOBUFS;
251}
252
Thomas Graf339bf982006-11-10 14:10:15 -0800253static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
254{
255 return nla_total_size(4) /* dst */
256 + nla_total_size(4) /* src */
257 + nla_total_size(4); /* flow */
258}
259
Denis V. Lunevae299fc2008-07-05 19:01:28 -0700260static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
Thomas Graf73417f62007-03-27 13:56:52 -0700261{
Nicolas Dichtelbafa6d92012-09-07 00:45:29 +0000262 rt_cache_flush(ops->fro_net);
Thomas Graf73417f62007-03-27 13:56:52 -0700263}
264
Andi Kleen04a6f822012-10-04 17:12:11 -0700265static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
Patrick McHardy25239ce2010-04-26 16:02:05 +0200266 .family = AF_INET,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700267 .rule_size = sizeof(struct fib4_rule),
Thomas Grafe1701c62007-03-24 12:46:02 -0700268 .addr_size = sizeof(u32),
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700269 .action = fib4_rule_action,
270 .match = fib4_rule_match,
271 .configure = fib4_rule_configure,
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700272 .delete = fib4_rule_delete,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700273 .compare = fib4_rule_compare,
274 .fill = fib4_rule_fill,
Patrick McHardyd8a566b2010-04-13 05:03:15 +0000275 .default_pref = fib_default_rule_pref,
Thomas Graf339bf982006-11-10 14:10:15 -0800276 .nlmsg_payload = fib4_rule_nlmsg_payload,
Thomas Graf73417f62007-03-27 13:56:52 -0700277 .flush_cache = fib4_rule_flush_cache,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700278 .nlgroup = RTNLGRP_IPV4_RULE,
279 .policy = fib4_rule_policy,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700280 .owner = THIS_MODULE,
281};
282
Denis V. Luneve4e49712008-01-10 03:27:51 -0800283static int fib_default_rules_init(struct fib_rules_ops *ops)
Denis V. Lunev2994c632007-11-10 22:12:03 -0800284{
285 int err;
286
Patrick McHardy5adef182009-12-03 01:25:57 +0000287 err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
Denis V. Lunev2994c632007-11-10 22:12:03 -0800288 if (err < 0)
289 return err;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800290 err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
Denis V. Lunev2994c632007-11-10 22:12:03 -0800291 if (err < 0)
292 return err;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800293 err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
Denis V. Lunev2994c632007-11-10 22:12:03 -0800294 if (err < 0)
295 return err;
296 return 0;
297}
298
Denis V. Lunev7b1a74f2008-01-10 03:22:17 -0800299int __net_init fib4_rules_init(struct net *net)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300{
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800301 int err;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800302 struct fib_rules_ops *ops;
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800303
Eric W. Biedermane9c51582009-12-03 12:22:55 -0800304 ops = fib_rules_register(&fib4_rules_ops_template, net);
305 if (IS_ERR(ops))
306 return PTR_ERR(ops);
Denis V. Luneve4e49712008-01-10 03:27:51 -0800307
308 err = fib_default_rules_init(ops);
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800309 if (err < 0)
310 goto fail;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800311 net->ipv4.rules_ops = ops;
David S. Millerf4530fa2012-07-05 22:13:13 -0700312 net->ipv4.fib_has_custom_rules = false;
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800313 return 0;
314
315fail:
316 /* also cleans all rules already added */
Denis V. Lunev9e3a5482008-01-20 16:46:41 -0800317 fib_rules_unregister(ops);
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800318 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319}
Denis V. Lunev7b1a74f2008-01-10 03:22:17 -0800320
321void __net_exit fib4_rules_exit(struct net *net)
322{
Denis V. Lunev9e3a5482008-01-20 16:46:41 -0800323 fib_rules_unregister(net->ipv4.rules_ops);
Denis V. Lunev7b1a74f2008-01-10 03:22:17 -0800324}