blob: f2bda9e89c61b251b66ed1201c14e568bd5078b3 [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
Andy Gospodarek0eeb0752015-06-23 13:45:37 -040050int __fib_lookup(struct net *net, struct flowi4 *flp,
51 struct fib_result *res, unsigned int flags)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070052{
53 struct fib_lookup_arg arg = {
54 .result = res,
Andy Gospodarek0eeb0752015-06-23 13:45:37 -040055 .flags = flags,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070056 };
57 int err;
58
David S. Miller22bd5b92011-03-11 19:54:08 -050059 err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
David S. Miller85b91b02012-07-13 08:21:29 -070060#ifdef CONFIG_IP_ROUTE_CLASSID
61 if (arg.rule)
62 res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
63 else
64 res->tclassid = 0;
65#endif
Panu Matilainen49dd18b2014-11-14 13:14:32 +020066
67 if (err == -ESRCH)
68 err = -ENETUNREACH;
69
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 return err;
71}
David S. Millerf4530fa2012-07-05 22:13:13 -070072EXPORT_SYMBOL_GPL(__fib_lookup);
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
Adrian Bunk8ce11e62006-08-07 21:50:48 -070074static int fib4_rule_action(struct fib_rule *rule, struct flowi *flp,
75 int flags, struct fib_lookup_arg *arg)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070076{
77 int err = -EAGAIN;
78 struct fib_table *tbl;
79
80 switch (rule->action) {
81 case FR_ACT_TO_TBL:
82 break;
83
84 case FR_ACT_UNREACHABLE:
Alexander Duyck345e9b52014-12-31 10:56:24 -080085 return -ENETUNREACH;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070086
87 case FR_ACT_PROHIBIT:
Alexander Duyck345e9b52014-12-31 10:56:24 -080088 return -EACCES;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070089
90 case FR_ACT_BLACKHOLE:
91 default:
Alexander Duyck345e9b52014-12-31 10:56:24 -080092 return -EINVAL;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070093 }
94
Alexander Duyck345e9b52014-12-31 10:56:24 -080095 rcu_read_lock();
Thomas Grafe1ef4bf2006-08-04 03:39:22 -070096
Alexander Duyck345e9b52014-12-31 10:56:24 -080097 tbl = fib_get_table(rule->fr_net, rule->table);
98 if (tbl)
99 err = fib_table_lookup(tbl, &flp->u.ip4,
100 (struct fib_result *)arg->result,
101 arg->flags);
102
103 rcu_read_unlock();
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700104 return err;
105}
106
Stefan Tomanek7764a452013-08-01 02:17:15 +0200107static bool fib4_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
108{
Stefan Tomanek6ef94cf2013-08-02 17:19:56 +0200109 struct fib_result *result = (struct fib_result *) arg->result;
Stefan Tomanek673498b2013-12-10 23:21:25 +0100110 struct net_device *dev = NULL;
111
112 if (result->fi)
113 dev = result->fi->fib_dev;
Stefan Tomanek6ef94cf2013-08-02 17:19:56 +0200114
Stefan Tomanek7764a452013-08-01 02:17:15 +0200115 /* do not accept result if the route does
116 * not meet the required prefix length
117 */
Stefan Tomanek73f56982013-08-03 14:14:43 +0200118 if (result->prefixlen <= rule->suppress_prefixlen)
Stefan Tomanek6ef94cf2013-08-02 17:19:56 +0200119 goto suppress_route;
120
121 /* do not accept result if the route uses a device
122 * belonging to a forbidden interface group
123 */
124 if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
125 goto suppress_route;
126
Stefan Tomanek7764a452013-08-01 02:17:15 +0200127 return false;
Stefan Tomanek6ef94cf2013-08-02 17:19:56 +0200128
129suppress_route:
130 if (!(arg->flags & FIB_LOOKUP_NOREF))
131 fib_info_put(result->fi);
132 return true;
Stefan Tomanek7764a452013-08-01 02:17:15 +0200133}
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700134
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700135static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
136{
137 struct fib4_rule *r = (struct fib4_rule *) rule;
David S. Miller9ade2282011-03-12 02:02:42 -0500138 struct flowi4 *fl4 = &fl->u.ip4;
139 __be32 daddr = fl4->daddr;
140 __be32 saddr = fl4->saddr;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700141
142 if (((saddr ^ r->src) & r->srcmask) ||
143 ((daddr ^ r->dst) & r->dstmask))
144 return 0;
145
David S. Miller9ade2282011-03-12 02:02:42 -0500146 if (r->tos && (r->tos != fl4->flowi4_tos))
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700147 return 0;
148
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700149 return 1;
150}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151
Denis V. Lunev8ad49422008-01-10 03:24:11 -0800152static struct fib_table *fib_empty_table(struct net *net)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153{
Patrick McHardy2dfe55b2006-08-10 23:08:33 -0700154 u32 id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155
156 for (id = 1; id <= RT_TABLE_MAX; id++)
Ian Morris51456b22015-04-03 09:17:26 +0100157 if (!fib_get_table(net, id))
Denis V. Lunev8ad49422008-01-10 03:24:11 -0800158 return fib_new_table(net, id);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 return NULL;
160}
161
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700162static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
Thomas Graf1f6c9552006-11-09 15:22:48 -0800163 FRA_GENERIC_POLICY,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700164 [FRA_FLOW] = { .type = NLA_U32 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165};
166
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700167static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
Rami Rosen8b3521e2009-05-11 05:52:49 +0000168 struct fib_rule_hdr *frh,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700169 struct nlattr **tb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170{
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900171 struct net *net = sock_net(skb->sk);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700172 int err = -EINVAL;
173 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174
Thomas Grafe1701c62007-03-24 12:46:02 -0700175 if (frh->tos & ~IPTOS_TOS_MASK)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700176 goto errout;
177
Alexander Duyck0ddcf432015-03-06 13:47:00 -0800178 /* split local/main if they are not already split */
179 err = fib_unmerge(net);
180 if (err)
181 goto errout;
182
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700183 if (rule->table == RT_TABLE_UNSPEC) {
184 if (rule->action == FR_ACT_TO_TBL) {
185 struct fib_table *table;
186
Denis V. Luneve4e49712008-01-10 03:27:51 -0800187 table = fib_empty_table(net);
Ian Morris51456b22015-04-03 09:17:26 +0100188 if (!table) {
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700189 err = -ENOBUFS;
190 goto errout;
191 }
192
193 rule->table = table->tb_id;
194 }
195 }
196
Thomas Grafe1701c62007-03-24 12:46:02 -0700197 if (frh->src_len)
Jiri Benc67b61f62015-03-29 16:59:26 +0200198 rule4->src = nla_get_in_addr(tb[FRA_SRC]);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700199
Thomas Grafe1701c62007-03-24 12:46:02 -0700200 if (frh->dst_len)
Jiri Benc67b61f62015-03-29 16:59:26 +0200201 rule4->dst = nla_get_in_addr(tb[FRA_DST]);
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700202
Patrick McHardyc7066f72011-01-14 13:36:42 +0100203#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700204 if (tb[FRA_FLOW]) {
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700205 rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700206 if (rule4->tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700207 net->ipv4.fib_num_tclassid_users++;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700208 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700211 rule4->src_len = frh->src_len;
212 rule4->srcmask = inet_make_mask(rule4->src_len);
213 rule4->dst_len = frh->dst_len;
214 rule4->dstmask = inet_make_mask(rule4->dst_len);
215 rule4->tos = frh->tos;
216
David S. Millerf4530fa2012-07-05 22:13:13 -0700217 net->ipv4.fib_has_custom_rules = true;
Scott Feldman104616e2015-03-05 21:21:16 -0800218 fib_flush_external(rule->fr_net);
219
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700220 err = 0;
221errout:
222 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223}
224
Alexander Duyck0ddcf432015-03-06 13:47:00 -0800225static int fib4_rule_delete(struct fib_rule *rule)
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700226{
David S. Millerf4530fa2012-07-05 22:13:13 -0700227 struct net *net = rule->fr_net;
Alexander Duyck0ddcf432015-03-06 13:47:00 -0800228 int err;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700229
Alexander Duyck0ddcf432015-03-06 13:47:00 -0800230 /* split local/main if they are not already split */
231 err = fib_unmerge(net);
232 if (err)
233 goto errout;
234
235#ifdef CONFIG_IP_ROUTE_CLASSID
236 if (((struct fib4_rule *)rule)->tclassid)
David S. Millerf4530fa2012-07-05 22:13:13 -0700237 net->ipv4.fib_num_tclassid_users--;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700238#endif
David S. Millerf4530fa2012-07-05 22:13:13 -0700239 net->ipv4.fib_has_custom_rules = true;
Scott Feldman104616e2015-03-05 21:21:16 -0800240 fib_flush_external(rule->fr_net);
Alexander Duyck0ddcf432015-03-06 13:47:00 -0800241errout:
242 return err;
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700243}
244
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700245static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
246 struct nlattr **tb)
Patrick McHardya5cdc032006-03-23 01:16:06 -0800247{
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700248 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
Patrick McHardya5cdc032006-03-23 01:16:06 -0800249
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700250 if (frh->src_len && (rule4->src_len != frh->src_len))
251 return 0;
252
253 if (frh->dst_len && (rule4->dst_len != frh->dst_len))
254 return 0;
255
256 if (frh->tos && (rule4->tos != frh->tos))
257 return 0;
258
Patrick McHardyc7066f72011-01-14 13:36:42 +0100259#ifdef CONFIG_IP_ROUTE_CLASSID
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700260 if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
261 return 0;
262#endif
263
Jiri Benc67b61f62015-03-29 16:59:26 +0200264 if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700265 return 0;
266
Jiri Benc67b61f62015-03-29 16:59:26 +0200267 if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700268 return 0;
269
270 return 1;
271}
272
273static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
Rami Rosen04af8cf2009-05-20 17:26:23 -0700274 struct fib_rule_hdr *frh)
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700275{
276 struct fib4_rule *rule4 = (struct fib4_rule *) rule;
277
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700278 frh->dst_len = rule4->dst_len;
279 frh->src_len = rule4->src_len;
280 frh->tos = rule4->tos;
281
David S. Millerf3756b72012-04-01 20:39:02 -0400282 if ((rule4->dst_len &&
Jiri Benc930345e2015-03-29 16:59:25 +0200283 nla_put_in_addr(skb, FRA_DST, rule4->dst)) ||
David S. Millerf3756b72012-04-01 20:39:02 -0400284 (rule4->src_len &&
Jiri Benc930345e2015-03-29 16:59:25 +0200285 nla_put_in_addr(skb, FRA_SRC, rule4->src)))
David S. Millerf3756b72012-04-01 20:39:02 -0400286 goto nla_put_failure;
Patrick McHardyc7066f72011-01-14 13:36:42 +0100287#ifdef CONFIG_IP_ROUTE_CLASSID
David S. Millerf3756b72012-04-01 20:39:02 -0400288 if (rule4->tclassid &&
289 nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
290 goto nla_put_failure;
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700291#endif
292 return 0;
293
294nla_put_failure:
295 return -ENOBUFS;
296}
297
Thomas Graf339bf982006-11-10 14:10:15 -0800298static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
299{
300 return nla_total_size(4) /* dst */
301 + nla_total_size(4) /* src */
302 + nla_total_size(4); /* flow */
303}
304
Denis V. Lunevae299fc2008-07-05 19:01:28 -0700305static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
Thomas Graf73417f62007-03-27 13:56:52 -0700306{
Nicolas Dichtelbafa6d92012-09-07 00:45:29 +0000307 rt_cache_flush(ops->fro_net);
Thomas Graf73417f62007-03-27 13:56:52 -0700308}
309
Andi Kleen04a6f822012-10-04 17:12:11 -0700310static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
Patrick McHardy25239ce2010-04-26 16:02:05 +0200311 .family = AF_INET,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700312 .rule_size = sizeof(struct fib4_rule),
Thomas Grafe1701c62007-03-24 12:46:02 -0700313 .addr_size = sizeof(u32),
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700314 .action = fib4_rule_action,
Stefan Tomanek7764a452013-08-01 02:17:15 +0200315 .suppress = fib4_rule_suppress,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700316 .match = fib4_rule_match,
317 .configure = fib4_rule_configure,
David S. Miller7a9bc9b2012-06-29 01:32:45 -0700318 .delete = fib4_rule_delete,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700319 .compare = fib4_rule_compare,
320 .fill = fib4_rule_fill,
Thomas Graf339bf982006-11-10 14:10:15 -0800321 .nlmsg_payload = fib4_rule_nlmsg_payload,
Thomas Graf73417f62007-03-27 13:56:52 -0700322 .flush_cache = fib4_rule_flush_cache,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700323 .nlgroup = RTNLGRP_IPV4_RULE,
324 .policy = fib4_rule_policy,
Thomas Grafe1ef4bf2006-08-04 03:39:22 -0700325 .owner = THIS_MODULE,
326};
327
Denis V. Luneve4e49712008-01-10 03:27:51 -0800328static int fib_default_rules_init(struct fib_rules_ops *ops)
Denis V. Lunev2994c632007-11-10 22:12:03 -0800329{
330 int err;
331
Patrick McHardy5adef182009-12-03 01:25:57 +0000332 err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
Denis V. Lunev2994c632007-11-10 22:12:03 -0800333 if (err < 0)
334 return err;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800335 err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
Denis V. Lunev2994c632007-11-10 22:12:03 -0800336 if (err < 0)
337 return err;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800338 err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
Denis V. Lunev2994c632007-11-10 22:12:03 -0800339 if (err < 0)
340 return err;
341 return 0;
342}
343
Denis V. Lunev7b1a74f2008-01-10 03:22:17 -0800344int __net_init fib4_rules_init(struct net *net)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345{
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800346 int err;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800347 struct fib_rules_ops *ops;
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800348
Eric W. Biedermane9c51582009-12-03 12:22:55 -0800349 ops = fib_rules_register(&fib4_rules_ops_template, net);
350 if (IS_ERR(ops))
351 return PTR_ERR(ops);
Denis V. Luneve4e49712008-01-10 03:27:51 -0800352
353 err = fib_default_rules_init(ops);
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800354 if (err < 0)
355 goto fail;
Denis V. Luneve4e49712008-01-10 03:27:51 -0800356 net->ipv4.rules_ops = ops;
David S. Millerf4530fa2012-07-05 22:13:13 -0700357 net->ipv4.fib_has_custom_rules = false;
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800358 return 0;
359
360fail:
361 /* also cleans all rules already added */
Denis V. Lunev9e3a5482008-01-20 16:46:41 -0800362 fib_rules_unregister(ops);
Denis V. Lunevdbb50162008-01-10 03:21:49 -0800363 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364}
Denis V. Lunev7b1a74f2008-01-10 03:22:17 -0800365
366void __net_exit fib4_rules_exit(struct net *net)
367{
Denis V. Lunev9e3a5482008-01-20 16:46:41 -0800368 fib_rules_unregister(net->ipv4.rules_ops);
Denis V. Lunev7b1a74f2008-01-10 03:22:17 -0800369}