2 * net/ipv6/fib6_rules.c IPv6 Routing Policy Rules
4 * Copyright (C)2003-2006 Helsinki University of Technology
5 * Copyright (C)2003-2006 USAGI/WIDE Project
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.
12 * Thomas Graf <tgraf@suug.ch>
13 * Ville Nuorvala <vnuorval@tcs.hut.fi>
16 #include <linux/netdevice.h>
17 #include <linux/export.h>
19 #include <net/fib_rules.h>
21 #include <net/addrconf.h>
22 #include <net/ip6_route.h>
23 #include <net/netlink.h>
26 struct fib_rule common;
32 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
33 int flags, pol_lookup_t lookup)
36 struct fib_lookup_arg arg = {
38 .flags = FIB_LOOKUP_NOREF,
41 fib_rules_lookup(net->ipv6.fib6_rules_ops,
42 flowi6_to_flowi(fl6), flags, &arg);
47 dst_hold(&net->ipv6.ip6_null_entry->dst);
48 return &net->ipv6.ip6_null_entry->dst;
51 if (rt->rt6i_flags & RTF_REJECT &&
52 rt->dst.error == -EAGAIN) {
54 rt = net->ipv6.ip6_null_entry;
61 static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
62 int flags, struct fib_lookup_arg *arg)
64 struct flowi6 *flp6 = &flp->u.ip6;
65 struct rt6_info *rt = NULL;
66 struct fib6_table *table;
67 struct net *net = rule->fr_net;
68 pol_lookup_t lookup = arg->lookup_ptr;
71 switch (rule->action) {
74 case FR_ACT_UNREACHABLE:
76 rt = net->ipv6.ip6_null_entry;
79 case FR_ACT_BLACKHOLE:
81 rt = net->ipv6.ip6_blk_hole_entry;
85 rt = net->ipv6.ip6_prohibit_entry;
89 table = fib6_get_table(net, rule->table);
95 rt = lookup(net, table, flp6, flags);
96 if (rt != net->ipv6.ip6_null_entry) {
97 struct fib6_rule *r = (struct fib6_rule *)rule;
100 * If we need to find a source address for this traffic,
101 * we check the result if it meets requirement of the rule.
103 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
104 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
105 struct in6_addr saddr;
107 if (ipv6_dev_get_saddr(net,
108 ip6_dst_idev(&rt->dst)->dev,
110 rt6_flags2srcprefs(flags),
113 if (!ipv6_prefix_equal(&saddr, &r->src.addr,
134 static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
136 struct rt6_info *rt = (struct rt6_info *) arg->result;
137 struct net_device *dev = NULL;
140 dev = rt->rt6i_idev->dev;
142 /* do not accept result if the route does
143 * not meet the required prefix length
145 if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
148 /* do not accept result if the route uses a device
149 * belonging to a forbidden interface group
151 if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
161 static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
163 struct fib6_rule *r = (struct fib6_rule *) rule;
164 struct flowi6 *fl6 = &fl->u.ip6;
167 !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
171 * If FIB_RULE_FIND_SADDR is set and we do not have a
172 * source address for the traffic, we defer check for
176 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
177 if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
180 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
184 if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel))
190 static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
194 static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
195 struct fib_rule_hdr *frh,
199 struct net *net = sock_net(skb->sk);
200 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
202 if (rule->action == FR_ACT_TO_TBL) {
203 if (rule->table == RT6_TABLE_UNSPEC)
206 if (fib6_new_table(net, rule->table) == NULL) {
213 rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
216 rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
218 rule6->src.plen = frh->src_len;
219 rule6->dst.plen = frh->dst_len;
220 rule6->tclass = frh->tos;
227 static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
230 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
232 if (frh->src_len && (rule6->src.plen != frh->src_len))
235 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
238 if (frh->tos && (rule6->tclass != frh->tos))
242 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
246 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
252 static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
253 struct fib_rule_hdr *frh)
255 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
257 frh->dst_len = rule6->dst.plen;
258 frh->src_len = rule6->src.plen;
259 frh->tos = rule6->tclass;
261 if ((rule6->dst.plen &&
262 nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) ||
264 nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
265 goto nla_put_failure;
272 static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
274 return nla_total_size(16) /* dst */
275 + nla_total_size(16); /* src */
278 static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
280 .rule_size = sizeof(struct fib6_rule),
281 .addr_size = sizeof(struct in6_addr),
282 .action = fib6_rule_action,
283 .match = fib6_rule_match,
284 .suppress = fib6_rule_suppress,
285 .configure = fib6_rule_configure,
286 .compare = fib6_rule_compare,
287 .fill = fib6_rule_fill,
288 .nlmsg_payload = fib6_rule_nlmsg_payload,
289 .nlgroup = RTNLGRP_IPV6_RULE,
290 .policy = fib6_rule_policy,
291 .owner = THIS_MODULE,
292 .fro_net = &init_net,
295 static int __net_init fib6_rules_net_init(struct net *net)
297 struct fib_rules_ops *ops;
300 ops = fib_rules_register(&fib6_rules_ops_template, net);
304 err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0);
306 goto out_fib6_rules_ops;
308 err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0);
310 goto out_fib6_rules_ops;
312 net->ipv6.fib6_rules_ops = ops;
317 fib_rules_unregister(ops);
321 static void __net_exit fib6_rules_net_exit(struct net *net)
324 fib_rules_unregister(net->ipv6.fib6_rules_ops);
328 static struct pernet_operations fib6_rules_net_ops = {
329 .init = fib6_rules_net_init,
330 .exit = fib6_rules_net_exit,
333 int __init fib6_rules_init(void)
335 return register_pernet_subsys(&fib6_rules_net_ops);
339 void fib6_rules_cleanup(void)
341 unregister_pernet_subsys(&fib6_rules_net_ops);