blob: 8d05527524e39063eb941494ec80e0678702a30b [file] [log] [blame]
Thomas Graf101367c2006-08-04 03:39:02 -07001/*
2 * net/ipv6/fib6_rules.c IPv6 Routing Policy Rules
3 *
4 * Copyright (C)2003-2006 Helsinki University of Technology
5 * Copyright (C)2003-2006 USAGI/WIDE Project
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation, version 2.
10 *
11 * Authors
12 * Thomas Graf <tgraf@suug.ch>
13 * Ville Nuorvala <vnuorval@tcs.hut.fi>
14 */
15
Thomas Graf101367c2006-08-04 03:39:02 -070016#include <linux/netdevice.h>
17
18#include <net/fib_rules.h>
19#include <net/ipv6.h>
YOSHIFUJI Hideaki29f6af72007-04-06 11:45:39 -070020#include <net/addrconf.h>
Thomas Graf101367c2006-08-04 03:39:02 -070021#include <net/ip6_route.h>
22#include <net/netlink.h>
23
24struct fib6_rule
25{
26 struct fib_rule common;
27 struct rt6key src;
28 struct rt6key dst;
29 u8 tclass;
30};
31
Daniel Lezcano58f09b72008-03-03 23:25:27 -080032struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl,
33 int flags, pol_lookup_t lookup)
Thomas Graf101367c2006-08-04 03:39:02 -070034{
35 struct fib_lookup_arg arg = {
36 .lookup_ptr = lookup,
37 };
38
Daniel Lezcanodcabb812008-03-03 23:33:08 -080039 fib_rules_lookup(net->ipv6.fib6_rules_ops, fl, flags, &arg);
Thomas Graf101367c2006-08-04 03:39:02 -070040 if (arg.rule)
41 fib_rule_put(arg.rule);
42
Ville Nuorvalab1429552006-08-08 16:44:17 -070043 if (arg.result)
YOSHIFUJI Hideaki40aa7b92006-10-19 13:50:09 +090044 return arg.result;
Ville Nuorvalab1429552006-08-08 16:44:17 -070045
Daniel Lezcano8ed67782008-03-04 13:48:30 -080046 dst_hold(&net->ipv6.ip6_null_entry->u.dst);
47 return &net->ipv6.ip6_null_entry->u.dst;
Thomas Graf101367c2006-08-04 03:39:02 -070048}
49
Adrian Bunk8ce11e62006-08-07 21:50:48 -070050static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
51 int flags, struct fib_lookup_arg *arg)
Thomas Graf101367c2006-08-04 03:39:02 -070052{
53 struct rt6_info *rt = NULL;
54 struct fib6_table *table;
Daniel Lezcano8ed67782008-03-04 13:48:30 -080055 struct net *net = rule->fr_net;
Thomas Graf101367c2006-08-04 03:39:02 -070056 pol_lookup_t lookup = arg->lookup_ptr;
57
58 switch (rule->action) {
59 case FR_ACT_TO_TBL:
60 break;
61 case FR_ACT_UNREACHABLE:
Daniel Lezcano8ed67782008-03-04 13:48:30 -080062 rt = net->ipv6.ip6_null_entry;
Thomas Graf101367c2006-08-04 03:39:02 -070063 goto discard_pkt;
64 default:
65 case FR_ACT_BLACKHOLE:
Daniel Lezcano8ed67782008-03-04 13:48:30 -080066 rt = net->ipv6.ip6_blk_hole_entry;
Thomas Graf101367c2006-08-04 03:39:02 -070067 goto discard_pkt;
68 case FR_ACT_PROHIBIT:
Daniel Lezcano8ed67782008-03-04 13:48:30 -080069 rt = net->ipv6.ip6_prohibit_entry;
Thomas Graf101367c2006-08-04 03:39:02 -070070 goto discard_pkt;
71 }
72
Daniel Lezcano8ed67782008-03-04 13:48:30 -080073 table = fib6_get_table(net, rule->table);
Thomas Graf101367c2006-08-04 03:39:02 -070074 if (table)
Daniel Lezcano8ed67782008-03-04 13:48:30 -080075 rt = lookup(net, table, flp, flags);
Thomas Graf101367c2006-08-04 03:39:02 -070076
Daniel Lezcano8ed67782008-03-04 13:48:30 -080077 if (rt != net->ipv6.ip6_null_entry) {
YOSHIFUJI Hideaki29f6af72007-04-06 11:45:39 -070078 struct fib6_rule *r = (struct fib6_rule *)rule;
79
80 /*
81 * If we need to find a source address for this traffic,
82 * we check the result if it meets requirement of the rule.
83 */
84 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
85 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
86 struct in6_addr saddr;
YOSHIFUJI Hideaki7cbca672008-03-25 09:37:42 +090087 unsigned int srcprefs = 0;
88
89 if (flags & RT6_LOOKUP_F_SRCPREF_TMP)
90 srcprefs |= IPV6_PREFER_SRC_TMP;
91 if (flags & RT6_LOOKUP_F_SRCPREF_PUBLIC)
92 srcprefs |= IPV6_PREFER_SRC_PUBLIC;
93 if (flags & RT6_LOOKUP_F_SRCPREF_COA)
94 srcprefs |= IPV6_PREFER_SRC_COA;
95
YOSHIFUJI Hideaki5e5f3f02008-03-03 21:44:34 +090096 if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev,
YOSHIFUJI Hideaki7cbca672008-03-25 09:37:42 +090097 &flp->fl6_dst, srcprefs,
98 &saddr))
YOSHIFUJI Hideaki29f6af72007-04-06 11:45:39 -070099 goto again;
100 if (!ipv6_prefix_equal(&saddr, &r->src.addr,
101 r->src.plen))
102 goto again;
103 ipv6_addr_copy(&flp->fl6_src, &saddr);
104 }
Thomas Graf101367c2006-08-04 03:39:02 -0700105 goto out;
YOSHIFUJI Hideaki29f6af72007-04-06 11:45:39 -0700106 }
107again:
Thomas Graf101367c2006-08-04 03:39:02 -0700108 dst_release(&rt->u.dst);
Patrick McHardy3226f6882006-08-06 22:24:08 -0700109 rt = NULL;
110 goto out;
111
Thomas Graf101367c2006-08-04 03:39:02 -0700112discard_pkt:
113 dst_hold(&rt->u.dst);
114out:
115 arg->result = rt;
116 return rt == NULL ? -EAGAIN : 0;
117}
118
119
120static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
121{
122 struct fib6_rule *r = (struct fib6_rule *) rule;
123
Thomas Grafadaa70b2006-10-13 15:01:03 -0700124 if (r->dst.plen &&
125 !ipv6_prefix_equal(&fl->fl6_dst, &r->dst.addr, r->dst.plen))
Thomas Graf101367c2006-08-04 03:39:02 -0700126 return 0;
127
YOSHIFUJI Hideaki29f6af72007-04-06 11:45:39 -0700128 /*
129 * If FIB_RULE_FIND_SADDR is set and we do not have a
130 * source address for the traffic, we defer check for
131 * source address.
132 */
Thomas Grafadaa70b2006-10-13 15:01:03 -0700133 if (r->src.plen) {
YOSHIFUJI Hideaki29f6af72007-04-06 11:45:39 -0700134 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
135 if (!ipv6_prefix_equal(&fl->fl6_src, &r->src.addr,
136 r->src.plen))
137 return 0;
138 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
Thomas Grafadaa70b2006-10-13 15:01:03 -0700139 return 0;
140 }
Thomas Graf101367c2006-08-04 03:39:02 -0700141
YOSHIFUJI Hideaki2cc67cc2006-08-21 19:18:57 +0900142 if (r->tclass && r->tclass != ((ntohl(fl->fl6_flowlabel) >> 20) & 0xff))
143 return 0;
144
Thomas Graf101367c2006-08-04 03:39:02 -0700145 return 1;
146}
147
Patrick McHardyef7c79e2007-06-05 12:38:30 -0700148static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
Thomas Graf1f6c9552006-11-09 15:22:48 -0800149 FRA_GENERIC_POLICY,
Thomas Graf101367c2006-08-04 03:39:02 -0700150};
151
152static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
153 struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
154 struct nlattr **tb)
155{
156 int err = -EINVAL;
YOSHIFUJI Hideaki3b1e0a62008-03-26 02:26:21 +0900157 struct net *net = sock_net(skb->sk);
Thomas Graf101367c2006-08-04 03:39:02 -0700158 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
159
Thomas Graf101367c2006-08-04 03:39:02 -0700160 if (rule->action == FR_ACT_TO_TBL) {
161 if (rule->table == RT6_TABLE_UNSPEC)
162 goto errout;
163
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800164 if (fib6_new_table(net, rule->table) == NULL) {
Thomas Graf101367c2006-08-04 03:39:02 -0700165 err = -ENOBUFS;
166 goto errout;
167 }
168 }
169
Thomas Grafe1701c62007-03-24 12:46:02 -0700170 if (frh->src_len)
Thomas Graf101367c2006-08-04 03:39:02 -0700171 nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
172 sizeof(struct in6_addr));
173
Thomas Grafe1701c62007-03-24 12:46:02 -0700174 if (frh->dst_len)
Thomas Graf101367c2006-08-04 03:39:02 -0700175 nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
176 sizeof(struct in6_addr));
177
178 rule6->src.plen = frh->src_len;
179 rule6->dst.plen = frh->dst_len;
180 rule6->tclass = frh->tos;
181
182 err = 0;
183errout:
184 return err;
185}
186
187static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
188 struct nlattr **tb)
189{
190 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
191
192 if (frh->src_len && (rule6->src.plen != frh->src_len))
193 return 0;
194
195 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
196 return 0;
197
198 if (frh->tos && (rule6->tclass != frh->tos))
199 return 0;
200
Thomas Grafe1701c62007-03-24 12:46:02 -0700201 if (frh->src_len &&
Thomas Graf101367c2006-08-04 03:39:02 -0700202 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
203 return 0;
204
Thomas Grafe1701c62007-03-24 12:46:02 -0700205 if (frh->dst_len &&
Thomas Graf101367c2006-08-04 03:39:02 -0700206 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
207 return 0;
208
209 return 1;
210}
211
212static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
213 struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
214{
215 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
216
217 frh->family = AF_INET6;
218 frh->dst_len = rule6->dst.plen;
219 frh->src_len = rule6->src.plen;
220 frh->tos = rule6->tclass;
221
222 if (rule6->dst.plen)
223 NLA_PUT(skb, FRA_DST, sizeof(struct in6_addr),
224 &rule6->dst.addr);
225
226 if (rule6->src.plen)
227 NLA_PUT(skb, FRA_SRC, sizeof(struct in6_addr),
228 &rule6->src.addr);
229
Thomas Graf101367c2006-08-04 03:39:02 -0700230 return 0;
231
232nla_put_failure:
233 return -ENOBUFS;
234}
235
Denis V. Lunev868d13a2008-01-10 03:18:25 -0800236static u32 fib6_rule_default_pref(struct fib_rules_ops *ops)
Thomas Graf101367c2006-08-04 03:39:02 -0700237{
238 return 0x3FFF;
239}
240
Thomas Graf339bf982006-11-10 14:10:15 -0800241static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
242{
243 return nla_total_size(16) /* dst */
244 + nla_total_size(16); /* src */
245}
246
Daniel Lezcanoeb5564b2008-03-03 23:32:30 -0800247static struct fib_rules_ops fib6_rules_ops_template = {
Thomas Graf101367c2006-08-04 03:39:02 -0700248 .family = AF_INET6,
249 .rule_size = sizeof(struct fib6_rule),
Thomas Grafe1701c62007-03-24 12:46:02 -0700250 .addr_size = sizeof(struct in6_addr),
Thomas Graf101367c2006-08-04 03:39:02 -0700251 .action = fib6_rule_action,
252 .match = fib6_rule_match,
253 .configure = fib6_rule_configure,
254 .compare = fib6_rule_compare,
255 .fill = fib6_rule_fill,
256 .default_pref = fib6_rule_default_pref,
Thomas Graf339bf982006-11-10 14:10:15 -0800257 .nlmsg_payload = fib6_rule_nlmsg_payload,
Thomas Graf101367c2006-08-04 03:39:02 -0700258 .nlgroup = RTNLGRP_IPV6_RULE,
259 .policy = fib6_rule_policy,
Thomas Graf101367c2006-08-04 03:39:02 -0700260 .owner = THIS_MODULE,
Denis V. Lunev035923832008-01-20 16:46:01 -0800261 .fro_net = &init_net,
Thomas Graf101367c2006-08-04 03:39:02 -0700262};
263
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800264static int fib6_rules_net_init(struct net *net)
Denis V. Lunev2994c632007-11-10 22:12:03 -0800265{
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800266 int err = -ENOMEM;
Denis V. Lunev2994c632007-11-10 22:12:03 -0800267
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800268 net->ipv6.fib6_rules_ops = kmemdup(&fib6_rules_ops_template,
269 sizeof(*net->ipv6.fib6_rules_ops),
270 GFP_KERNEL);
271 if (!net->ipv6.fib6_rules_ops)
Daniel Lezcano9eb87f32007-12-07 00:42:52 -0800272 goto out;
273
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800274 net->ipv6.fib6_rules_ops->fro_net = net;
275 INIT_LIST_HEAD(&net->ipv6.fib6_rules_ops->rules_list);
Daniel Lezcano9eb87f32007-12-07 00:42:52 -0800276
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800277 err = fib_default_rule_add(net->ipv6.fib6_rules_ops, 0,
278 RT6_TABLE_LOCAL, FIB_RULE_PERMANENT);
279 if (err)
280 goto out_fib6_rules_ops;
281
282 err = fib_default_rule_add(net->ipv6.fib6_rules_ops,
283 0x7FFE, RT6_TABLE_MAIN, 0);
284 if (err)
285 goto out_fib6_default_rule_add;
286
287 err = fib_rules_register(net->ipv6.fib6_rules_ops);
288 if (err)
289 goto out_fib6_default_rule_add;
290out:
291 return err;
292
293out_fib6_default_rule_add:
294 fib_rules_cleanup_ops(net->ipv6.fib6_rules_ops);
295out_fib6_rules_ops:
296 kfree(net->ipv6.fib6_rules_ops);
Daniel Lezcano9eb87f32007-12-07 00:42:52 -0800297 goto out;
Thomas Graf101367c2006-08-04 03:39:02 -0700298}
299
Daniel Lezcanodcabb812008-03-03 23:33:08 -0800300static void fib6_rules_net_exit(struct net *net)
301{
302 fib_rules_unregister(net->ipv6.fib6_rules_ops);
303 kfree(net->ipv6.fib6_rules_ops);
304}
305
306static struct pernet_operations fib6_rules_net_ops = {
307 .init = fib6_rules_net_init,
308 .exit = fib6_rules_net_exit,
309};
310
311int __init fib6_rules_init(void)
312{
313 return register_pernet_subsys(&fib6_rules_net_ops);
314}
315
316
Thomas Graf101367c2006-08-04 03:39:02 -0700317void fib6_rules_cleanup(void)
318{
YOSHIFUJI Hideakiff4e1fb2008-04-10 15:41:28 +0900319 unregister_pernet_subsys(&fib6_rules_net_ops);
Thomas Graf101367c2006-08-04 03:39:02 -0700320}