Commit | Line | Data |
---|---|---|
101367c2 TG |
1 | /* |
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 | ||
101367c2 | 16 | #include <linux/netdevice.h> |
bc3b2d7f | 17 | #include <linux/export.h> |
101367c2 TG |
18 | |
19 | #include <net/fib_rules.h> | |
20 | #include <net/ipv6.h> | |
29f6af77 | 21 | #include <net/addrconf.h> |
101367c2 TG |
22 | #include <net/ip6_route.h> |
23 | #include <net/netlink.h> | |
24 | ||
911c8541 | 25 | struct fib6_rule { |
101367c2 TG |
26 | struct fib_rule common; |
27 | struct rt6key src; | |
28 | struct rt6key dst; | |
29 | u8 tclass; | |
30 | }; | |
31 | ||
4c9483b2 | 32 | struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, |
58f09b78 | 33 | int flags, pol_lookup_t lookup) |
101367c2 | 34 | { |
ab997ad4 | 35 | struct rt6_info *rt; |
101367c2 TG |
36 | struct fib_lookup_arg arg = { |
37 | .lookup_ptr = lookup, | |
2c1c0004 | 38 | .flags = FIB_LOOKUP_NOREF, |
101367c2 TG |
39 | }; |
40 | ||
4c9483b2 DM |
41 | fib_rules_lookup(net->ipv6.fib6_rules_ops, |
42 | flowi6_to_flowi(fl6), flags, &arg); | |
101367c2 | 43 | |
ab997ad4 | 44 | rt = arg.result; |
b1429553 | 45 | |
ab997ad4 | 46 | if (!rt) { |
47 | dst_hold(&net->ipv6.ip6_null_entry->dst); | |
48 | return &net->ipv6.ip6_null_entry->dst; | |
49 | } | |
50 | ||
51 | if (rt->rt6i_flags & RTF_REJECT && | |
52 | rt->dst.error == -EAGAIN) { | |
53 | ip6_rt_put(rt); | |
54 | rt = net->ipv6.ip6_null_entry; | |
55 | dst_hold(&rt->dst); | |
56 | } | |
57 | ||
58 | return &rt->dst; | |
101367c2 TG |
59 | } |
60 | ||
8ce11e6a AB |
61 | static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp, |
62 | int flags, struct fib_lookup_arg *arg) | |
101367c2 | 63 | { |
4c9483b2 | 64 | struct flowi6 *flp6 = &flp->u.ip6; |
101367c2 TG |
65 | struct rt6_info *rt = NULL; |
66 | struct fib6_table *table; | |
8ed67789 | 67 | struct net *net = rule->fr_net; |
101367c2 | 68 | pol_lookup_t lookup = arg->lookup_ptr; |
46b3a421 | 69 | int err = 0; |
101367c2 TG |
70 | |
71 | switch (rule->action) { | |
72 | case FR_ACT_TO_TBL: | |
73 | break; | |
74 | case FR_ACT_UNREACHABLE: | |
46b3a421 | 75 | err = -ENETUNREACH; |
8ed67789 | 76 | rt = net->ipv6.ip6_null_entry; |
101367c2 TG |
77 | goto discard_pkt; |
78 | default: | |
79 | case FR_ACT_BLACKHOLE: | |
46b3a421 | 80 | err = -EINVAL; |
8ed67789 | 81 | rt = net->ipv6.ip6_blk_hole_entry; |
101367c2 TG |
82 | goto discard_pkt; |
83 | case FR_ACT_PROHIBIT: | |
46b3a421 | 84 | err = -EACCES; |
8ed67789 | 85 | rt = net->ipv6.ip6_prohibit_entry; |
101367c2 TG |
86 | goto discard_pkt; |
87 | } | |
88 | ||
8ed67789 | 89 | table = fib6_get_table(net, rule->table); |
46b3a421 HFS |
90 | if (!table) { |
91 | err = -EAGAIN; | |
92 | goto out; | |
93 | } | |
101367c2 | 94 | |
46b3a421 | 95 | rt = lookup(net, table, flp6, flags); |
8ed67789 | 96 | if (rt != net->ipv6.ip6_null_entry) { |
29f6af77 YH |
97 | struct fib6_rule *r = (struct fib6_rule *)rule; |
98 | ||
99 | /* | |
100 | * If we need to find a source address for this traffic, | |
101 | * we check the result if it meets requirement of the rule. | |
102 | */ | |
103 | if ((rule->flags & FIB_RULE_FIND_SADDR) && | |
104 | r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) { | |
105 | struct in6_addr saddr; | |
7cbca67c | 106 | |
191cd582 | 107 | if (ipv6_dev_get_saddr(net, |
d8d1f30b | 108 | ip6_dst_idev(&rt->dst)->dev, |
4c9483b2 | 109 | &flp6->daddr, |
0c9a2ac1 | 110 | rt6_flags2srcprefs(flags), |
7cbca67c | 111 | &saddr)) |
29f6af77 YH |
112 | goto again; |
113 | if (!ipv6_prefix_equal(&saddr, &r->src.addr, | |
114 | r->src.plen)) | |
115 | goto again; | |
4e3fd7a0 | 116 | flp6->saddr = saddr; |
29f6af77 | 117 | } |
73ba57bf | 118 | err = rt->dst.error; |
101367c2 | 119 | goto out; |
29f6af77 YH |
120 | } |
121 | again: | |
94e187c0 | 122 | ip6_rt_put(rt); |
46b3a421 | 123 | err = -EAGAIN; |
3226f688 PM |
124 | rt = NULL; |
125 | goto out; | |
126 | ||
101367c2 | 127 | discard_pkt: |
d8d1f30b | 128 | dst_hold(&rt->dst); |
101367c2 TG |
129 | out: |
130 | arg->result = rt; | |
46b3a421 | 131 | return err; |
101367c2 TG |
132 | } |
133 | ||
7764a45a ST |
134 | static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg) |
135 | { | |
136 | struct rt6_info *rt = (struct rt6_info *) arg->result; | |
673498b8 ST |
137 | struct net_device *dev = NULL; |
138 | ||
139 | if (rt->rt6i_idev) | |
140 | dev = rt->rt6i_idev->dev; | |
141 | ||
7764a45a ST |
142 | /* do not accept result if the route does |
143 | * not meet the required prefix length | |
144 | */ | |
73f5698e | 145 | if (rt->rt6i_dst.plen <= rule->suppress_prefixlen) |
6ef94cfa ST |
146 | goto suppress_route; |
147 | ||
148 | /* do not accept result if the route uses a device | |
149 | * belonging to a forbidden interface group | |
150 | */ | |
151 | if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup) | |
152 | goto suppress_route; | |
153 | ||
154 | return false; | |
155 | ||
156 | suppress_route: | |
04f0888d ST |
157 | ip6_rt_put(rt); |
158 | return true; | |
7764a45a | 159 | } |
101367c2 TG |
160 | |
161 | static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags) | |
162 | { | |
163 | struct fib6_rule *r = (struct fib6_rule *) rule; | |
4c9483b2 | 164 | struct flowi6 *fl6 = &fl->u.ip6; |
101367c2 | 165 | |
adaa70bb | 166 | if (r->dst.plen && |
4c9483b2 | 167 | !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen)) |
101367c2 TG |
168 | return 0; |
169 | ||
29f6af77 YH |
170 | /* |
171 | * If FIB_RULE_FIND_SADDR is set and we do not have a | |
172 | * source address for the traffic, we defer check for | |
173 | * source address. | |
174 | */ | |
adaa70bb | 175 | if (r->src.plen) { |
29f6af77 | 176 | if (flags & RT6_LOOKUP_F_HAS_SADDR) { |
4c9483b2 | 177 | if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr, |
29f6af77 YH |
178 | r->src.plen)) |
179 | return 0; | |
180 | } else if (!(r->common.flags & FIB_RULE_FIND_SADDR)) | |
adaa70bb TG |
181 | return 0; |
182 | } | |
101367c2 | 183 | |
d76ed22b | 184 | if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel)) |
2cc67cc7 YH |
185 | return 0; |
186 | ||
101367c2 TG |
187 | return 1; |
188 | } | |
189 | ||
ef7c79ed | 190 | static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = { |
1f6c9557 | 191 | FRA_GENERIC_POLICY, |
101367c2 TG |
192 | }; |
193 | ||
194 | static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb, | |
8b3521ee | 195 | struct fib_rule_hdr *frh, |
101367c2 TG |
196 | struct nlattr **tb) |
197 | { | |
198 | int err = -EINVAL; | |
3b1e0a65 | 199 | struct net *net = sock_net(skb->sk); |
101367c2 TG |
200 | struct fib6_rule *rule6 = (struct fib6_rule *) rule; |
201 | ||
101367c2 TG |
202 | if (rule->action == FR_ACT_TO_TBL) { |
203 | if (rule->table == RT6_TABLE_UNSPEC) | |
204 | goto errout; | |
205 | ||
dcabb819 | 206 | if (fib6_new_table(net, rule->table) == NULL) { |
101367c2 TG |
207 | err = -ENOBUFS; |
208 | goto errout; | |
209 | } | |
210 | } | |
211 | ||
e1701c68 | 212 | if (frh->src_len) |
67b61f6c | 213 | rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]); |
101367c2 | 214 | |
e1701c68 | 215 | if (frh->dst_len) |
67b61f6c | 216 | rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]); |
101367c2 TG |
217 | |
218 | rule6->src.plen = frh->src_len; | |
219 | rule6->dst.plen = frh->dst_len; | |
220 | rule6->tclass = frh->tos; | |
221 | ||
222 | err = 0; | |
223 | errout: | |
224 | return err; | |
225 | } | |
226 | ||
227 | static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, | |
228 | struct nlattr **tb) | |
229 | { | |
230 | struct fib6_rule *rule6 = (struct fib6_rule *) rule; | |
231 | ||
232 | if (frh->src_len && (rule6->src.plen != frh->src_len)) | |
233 | return 0; | |
234 | ||
235 | if (frh->dst_len && (rule6->dst.plen != frh->dst_len)) | |
236 | return 0; | |
237 | ||
238 | if (frh->tos && (rule6->tclass != frh->tos)) | |
239 | return 0; | |
240 | ||
e1701c68 | 241 | if (frh->src_len && |
101367c2 TG |
242 | nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr))) |
243 | return 0; | |
244 | ||
e1701c68 | 245 | if (frh->dst_len && |
101367c2 TG |
246 | nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr))) |
247 | return 0; | |
248 | ||
249 | return 1; | |
250 | } | |
251 | ||
252 | static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb, | |
04af8cf6 | 253 | struct fib_rule_hdr *frh) |
101367c2 TG |
254 | { |
255 | struct fib6_rule *rule6 = (struct fib6_rule *) rule; | |
256 | ||
101367c2 TG |
257 | frh->dst_len = rule6->dst.plen; |
258 | frh->src_len = rule6->src.plen; | |
259 | frh->tos = rule6->tclass; | |
260 | ||
c78679e8 | 261 | if ((rule6->dst.plen && |
930345ea | 262 | nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) || |
c78679e8 | 263 | (rule6->src.plen && |
930345ea | 264 | nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr))) |
c78679e8 | 265 | goto nla_put_failure; |
101367c2 TG |
266 | return 0; |
267 | ||
268 | nla_put_failure: | |
269 | return -ENOBUFS; | |
270 | } | |
271 | ||
339bf98f TG |
272 | static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule) |
273 | { | |
274 | return nla_total_size(16) /* dst */ | |
275 | + nla_total_size(16); /* src */ | |
276 | } | |
277 | ||
04a6f82c | 278 | static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = { |
25239cee | 279 | .family = AF_INET6, |
101367c2 | 280 | .rule_size = sizeof(struct fib6_rule), |
e1701c68 | 281 | .addr_size = sizeof(struct in6_addr), |
101367c2 TG |
282 | .action = fib6_rule_action, |
283 | .match = fib6_rule_match, | |
7764a45a | 284 | .suppress = fib6_rule_suppress, |
101367c2 TG |
285 | .configure = fib6_rule_configure, |
286 | .compare = fib6_rule_compare, | |
287 | .fill = fib6_rule_fill, | |
339bf98f | 288 | .nlmsg_payload = fib6_rule_nlmsg_payload, |
101367c2 TG |
289 | .nlgroup = RTNLGRP_IPV6_RULE, |
290 | .policy = fib6_rule_policy, | |
101367c2 | 291 | .owner = THIS_MODULE, |
03592383 | 292 | .fro_net = &init_net, |
101367c2 TG |
293 | }; |
294 | ||
2c8c1e72 | 295 | static int __net_init fib6_rules_net_init(struct net *net) |
101367c2 | 296 | { |
e9c5158a | 297 | struct fib_rules_ops *ops; |
dcabb819 | 298 | int err = -ENOMEM; |
2994c638 | 299 | |
e9c5158a EB |
300 | ops = fib_rules_register(&fib6_rules_ops_template, net); |
301 | if (IS_ERR(ops)) | |
302 | return PTR_ERR(ops); | |
eb5564b8 | 303 | |
85b99092 | 304 | err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0); |
dcabb819 DL |
305 | if (err) |
306 | goto out_fib6_rules_ops; | |
9eb87f3f | 307 | |
85b99092 | 308 | err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0); |
dcabb819 | 309 | if (err) |
e9c5158a | 310 | goto out_fib6_rules_ops; |
9eb87f3f | 311 | |
85b99092 | 312 | net->ipv6.fib6_rules_ops = ops; |
9eb87f3f | 313 | out: |
dcabb819 | 314 | return err; |
9eb87f3f | 315 | |
dcabb819 | 316 | out_fib6_rules_ops: |
e9c5158a | 317 | fib_rules_unregister(ops); |
9eb87f3f | 318 | goto out; |
101367c2 TG |
319 | } |
320 | ||
2c8c1e72 | 321 | static void __net_exit fib6_rules_net_exit(struct net *net) |
dcabb819 | 322 | { |
419df12f | 323 | rtnl_lock(); |
dcabb819 | 324 | fib_rules_unregister(net->ipv6.fib6_rules_ops); |
419df12f | 325 | rtnl_unlock(); |
dcabb819 DL |
326 | } |
327 | ||
328 | static struct pernet_operations fib6_rules_net_ops = { | |
329 | .init = fib6_rules_net_init, | |
330 | .exit = fib6_rules_net_exit, | |
331 | }; | |
332 | ||
333 | int __init fib6_rules_init(void) | |
334 | { | |
335 | return register_pernet_subsys(&fib6_rules_net_ops); | |
336 | } | |
337 | ||
338 | ||
101367c2 TG |
339 | void fib6_rules_cleanup(void) |
340 | { | |
ff4e1fb0 | 341 | unregister_pernet_subsys(&fib6_rules_net_ops); |
101367c2 | 342 | } |