Commit | Line | Data |
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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> |
dcb18f76 | 17 | #include <linux/notifier.h> |
bc3b2d7f | 18 | #include <linux/export.h> |
101367c2 TG |
19 | |
20 | #include <net/fib_rules.h> | |
21 | #include <net/ipv6.h> | |
29f6af77 | 22 | #include <net/addrconf.h> |
101367c2 TG |
23 | #include <net/ip6_route.h> |
24 | #include <net/netlink.h> | |
25 | ||
911c8541 | 26 | struct fib6_rule { |
101367c2 TG |
27 | struct fib_rule common; |
28 | struct rt6key src; | |
29 | struct rt6key dst; | |
30 | u8 tclass; | |
31 | }; | |
32 | ||
e3ea9731 IS |
33 | static bool fib6_rule_matchall(const struct fib_rule *rule) |
34 | { | |
35 | struct fib6_rule *r = container_of(rule, struct fib6_rule, common); | |
36 | ||
37 | if (r->dst.plen || r->src.plen || r->tclass) | |
38 | return false; | |
39 | return fib_rule_matchall(rule); | |
40 | } | |
41 | ||
42 | bool fib6_rule_default(const struct fib_rule *rule) | |
43 | { | |
44 | if (!fib6_rule_matchall(rule) || rule->action != FR_ACT_TO_TBL || | |
45 | rule->l3mdev) | |
46 | return false; | |
47 | if (rule->table != RT6_TABLE_LOCAL && rule->table != RT6_TABLE_MAIN) | |
48 | return false; | |
49 | return true; | |
50 | } | |
51 | EXPORT_SYMBOL_GPL(fib6_rule_default); | |
52 | ||
dcb18f76 IS |
53 | int fib6_rules_dump(struct net *net, struct notifier_block *nb) |
54 | { | |
55 | return fib_rules_dump(net, nb, AF_INET6); | |
56 | } | |
57 | ||
58 | unsigned int fib6_rules_seq_read(struct net *net) | |
59 | { | |
60 | return fib_rules_seq_read(net, AF_INET6); | |
61 | } | |
62 | ||
138118ec DA |
63 | /* called with rcu lock held; no reference taken on fib6_info */ |
64 | struct fib6_info *fib6_lookup(struct net *net, int oif, struct flowi6 *fl6, | |
65 | int flags) | |
66 | { | |
67 | struct fib6_info *f6i; | |
68 | int err; | |
69 | ||
70 | if (net->ipv6.fib6_has_custom_rules) { | |
71 | struct fib_lookup_arg arg = { | |
72 | .lookup_ptr = fib6_table_lookup, | |
73 | .lookup_data = &oif, | |
74 | .flags = FIB_LOOKUP_NOREF, | |
75 | }; | |
76 | ||
77 | l3mdev_update_flow(net, flowi6_to_flowi(fl6)); | |
78 | ||
79 | err = fib_rules_lookup(net->ipv6.fib6_rules_ops, | |
80 | flowi6_to_flowi(fl6), flags, &arg); | |
81 | if (err) | |
82 | return ERR_PTR(err); | |
83 | ||
84 | f6i = arg.result ? : net->ipv6.fib6_null_entry; | |
85 | } else { | |
86 | f6i = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, | |
87 | oif, fl6, flags); | |
88 | if (!f6i || f6i == net->ipv6.fib6_null_entry) | |
89 | f6i = fib6_table_lookup(net, net->ipv6.fib6_main_tbl, | |
90 | oif, fl6, flags); | |
91 | } | |
92 | ||
93 | return f6i; | |
94 | } | |
95 | ||
4c9483b2 | 96 | struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, |
b75cc8f9 | 97 | const struct sk_buff *skb, |
58f09b78 | 98 | int flags, pol_lookup_t lookup) |
101367c2 | 99 | { |
feca7d8c VB |
100 | if (net->ipv6.fib6_has_custom_rules) { |
101 | struct fib_lookup_arg arg = { | |
102 | .lookup_ptr = lookup, | |
b75cc8f9 | 103 | .lookup_data = skb, |
feca7d8c VB |
104 | .flags = FIB_LOOKUP_NOREF, |
105 | }; | |
106 | ||
107 | /* update flow if oif or iif point to device enslaved to l3mdev */ | |
108 | l3mdev_update_flow(net, flowi6_to_flowi(fl6)); | |
109 | ||
110 | fib_rules_lookup(net->ipv6.fib6_rules_ops, | |
111 | flowi6_to_flowi(fl6), flags, &arg); | |
112 | ||
113 | if (arg.result) | |
114 | return arg.result; | |
115 | } else { | |
116 | struct rt6_info *rt; | |
117 | ||
b75cc8f9 | 118 | rt = lookup(net, net->ipv6.fib6_local_tbl, fl6, skb, flags); |
feca7d8c VB |
119 | if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN) |
120 | return &rt->dst; | |
121 | ip6_rt_put(rt); | |
b75cc8f9 | 122 | rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags); |
feca7d8c VB |
123 | if (rt->dst.error != -EAGAIN) |
124 | return &rt->dst; | |
125 | ip6_rt_put(rt); | |
126 | } | |
b1429553 | 127 | |
07f61557 SP |
128 | dst_hold(&net->ipv6.ip6_null_entry->dst); |
129 | return &net->ipv6.ip6_null_entry->dst; | |
101367c2 TG |
130 | } |
131 | ||
cc065a9e DA |
132 | static int fib6_rule_saddr(struct net *net, struct fib_rule *rule, int flags, |
133 | struct flowi6 *flp6, const struct net_device *dev) | |
134 | { | |
135 | struct fib6_rule *r = (struct fib6_rule *)rule; | |
136 | ||
137 | /* If we need to find a source address for this traffic, | |
138 | * we check the result if it meets requirement of the rule. | |
139 | */ | |
140 | if ((rule->flags & FIB_RULE_FIND_SADDR) && | |
141 | r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) { | |
142 | struct in6_addr saddr; | |
143 | ||
144 | if (ipv6_dev_get_saddr(net, dev, &flp6->daddr, | |
145 | rt6_flags2srcprefs(flags), &saddr)) | |
146 | return -EAGAIN; | |
147 | ||
148 | if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen)) | |
149 | return -EAGAIN; | |
150 | ||
151 | flp6->saddr = saddr; | |
152 | } | |
153 | ||
154 | return 0; | |
155 | } | |
156 | ||
138118ec DA |
157 | static int fib6_rule_action_alt(struct fib_rule *rule, struct flowi *flp, |
158 | int flags, struct fib_lookup_arg *arg) | |
159 | { | |
160 | struct flowi6 *flp6 = &flp->u.ip6; | |
161 | struct net *net = rule->fr_net; | |
162 | struct fib6_table *table; | |
163 | struct fib6_info *f6i; | |
164 | int err = -EAGAIN, *oif; | |
165 | u32 tb_id; | |
166 | ||
167 | switch (rule->action) { | |
168 | case FR_ACT_TO_TBL: | |
169 | break; | |
170 | case FR_ACT_UNREACHABLE: | |
171 | return -ENETUNREACH; | |
172 | case FR_ACT_PROHIBIT: | |
173 | return -EACCES; | |
174 | case FR_ACT_BLACKHOLE: | |
175 | default: | |
176 | return -EINVAL; | |
177 | } | |
178 | ||
179 | tb_id = fib_rule_get_table(rule, arg); | |
180 | table = fib6_get_table(net, tb_id); | |
181 | if (!table) | |
182 | return -EAGAIN; | |
183 | ||
184 | oif = (int *)arg->lookup_data; | |
185 | f6i = fib6_table_lookup(net, table, *oif, flp6, flags); | |
186 | if (f6i != net->ipv6.fib6_null_entry) { | |
187 | err = fib6_rule_saddr(net, rule, flags, flp6, | |
188 | fib6_info_nh_dev(f6i)); | |
189 | ||
190 | if (likely(!err)) | |
191 | arg->result = f6i; | |
192 | } | |
193 | ||
194 | return err; | |
195 | } | |
196 | ||
197 | static int __fib6_rule_action(struct fib_rule *rule, struct flowi *flp, | |
198 | int flags, struct fib_lookup_arg *arg) | |
101367c2 | 199 | { |
4c9483b2 | 200 | struct flowi6 *flp6 = &flp->u.ip6; |
101367c2 TG |
201 | struct rt6_info *rt = NULL; |
202 | struct fib6_table *table; | |
8ed67789 | 203 | struct net *net = rule->fr_net; |
101367c2 | 204 | pol_lookup_t lookup = arg->lookup_ptr; |
46b3a421 | 205 | int err = 0; |
96c63fa7 | 206 | u32 tb_id; |
101367c2 TG |
207 | |
208 | switch (rule->action) { | |
209 | case FR_ACT_TO_TBL: | |
210 | break; | |
211 | case FR_ACT_UNREACHABLE: | |
46b3a421 | 212 | err = -ENETUNREACH; |
8ed67789 | 213 | rt = net->ipv6.ip6_null_entry; |
101367c2 TG |
214 | goto discard_pkt; |
215 | default: | |
216 | case FR_ACT_BLACKHOLE: | |
46b3a421 | 217 | err = -EINVAL; |
8ed67789 | 218 | rt = net->ipv6.ip6_blk_hole_entry; |
101367c2 TG |
219 | goto discard_pkt; |
220 | case FR_ACT_PROHIBIT: | |
46b3a421 | 221 | err = -EACCES; |
8ed67789 | 222 | rt = net->ipv6.ip6_prohibit_entry; |
101367c2 TG |
223 | goto discard_pkt; |
224 | } | |
225 | ||
96c63fa7 DA |
226 | tb_id = fib_rule_get_table(rule, arg); |
227 | table = fib6_get_table(net, tb_id); | |
46b3a421 HFS |
228 | if (!table) { |
229 | err = -EAGAIN; | |
230 | goto out; | |
231 | } | |
101367c2 | 232 | |
b75cc8f9 | 233 | rt = lookup(net, table, flp6, arg->lookup_data, flags); |
8ed67789 | 234 | if (rt != net->ipv6.ip6_null_entry) { |
cc065a9e DA |
235 | err = fib6_rule_saddr(net, rule, flags, flp6, |
236 | ip6_dst_idev(&rt->dst)->dev); | |
237 | ||
238 | if (err == -EAGAIN) | |
239 | goto again; | |
240 | ||
73ba57bf | 241 | err = rt->dst.error; |
07f61557 SP |
242 | if (err != -EAGAIN) |
243 | goto out; | |
29f6af77 YH |
244 | } |
245 | again: | |
94e187c0 | 246 | ip6_rt_put(rt); |
46b3a421 | 247 | err = -EAGAIN; |
3226f688 PM |
248 | rt = NULL; |
249 | goto out; | |
250 | ||
101367c2 | 251 | discard_pkt: |
d8d1f30b | 252 | dst_hold(&rt->dst); |
101367c2 TG |
253 | out: |
254 | arg->result = rt; | |
46b3a421 | 255 | return err; |
101367c2 TG |
256 | } |
257 | ||
138118ec DA |
258 | static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp, |
259 | int flags, struct fib_lookup_arg *arg) | |
260 | { | |
261 | if (arg->lookup_ptr == fib6_table_lookup) | |
262 | return fib6_rule_action_alt(rule, flp, flags, arg); | |
263 | ||
264 | return __fib6_rule_action(rule, flp, flags, arg); | |
265 | } | |
266 | ||
7764a45a ST |
267 | static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg) |
268 | { | |
269 | struct rt6_info *rt = (struct rt6_info *) arg->result; | |
673498b8 ST |
270 | struct net_device *dev = NULL; |
271 | ||
272 | if (rt->rt6i_idev) | |
273 | dev = rt->rt6i_idev->dev; | |
274 | ||
7764a45a ST |
275 | /* do not accept result if the route does |
276 | * not meet the required prefix length | |
277 | */ | |
73f5698e | 278 | if (rt->rt6i_dst.plen <= rule->suppress_prefixlen) |
6ef94cfa ST |
279 | goto suppress_route; |
280 | ||
281 | /* do not accept result if the route uses a device | |
282 | * belonging to a forbidden interface group | |
283 | */ | |
284 | if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup) | |
285 | goto suppress_route; | |
286 | ||
287 | return false; | |
288 | ||
289 | suppress_route: | |
04f0888d ST |
290 | ip6_rt_put(rt); |
291 | return true; | |
7764a45a | 292 | } |
101367c2 TG |
293 | |
294 | static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags) | |
295 | { | |
296 | struct fib6_rule *r = (struct fib6_rule *) rule; | |
4c9483b2 | 297 | struct flowi6 *fl6 = &fl->u.ip6; |
101367c2 | 298 | |
adaa70bb | 299 | if (r->dst.plen && |
4c9483b2 | 300 | !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen)) |
101367c2 TG |
301 | return 0; |
302 | ||
29f6af77 YH |
303 | /* |
304 | * If FIB_RULE_FIND_SADDR is set and we do not have a | |
305 | * source address for the traffic, we defer check for | |
306 | * source address. | |
307 | */ | |
adaa70bb | 308 | if (r->src.plen) { |
29f6af77 | 309 | if (flags & RT6_LOOKUP_F_HAS_SADDR) { |
4c9483b2 | 310 | if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr, |
29f6af77 YH |
311 | r->src.plen)) |
312 | return 0; | |
313 | } else if (!(r->common.flags & FIB_RULE_FIND_SADDR)) | |
adaa70bb TG |
314 | return 0; |
315 | } | |
101367c2 | 316 | |
d76ed22b | 317 | if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel)) |
2cc67cc7 YH |
318 | return 0; |
319 | ||
bb0ad198 RP |
320 | if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto)) |
321 | return 0; | |
322 | ||
323 | if (fib_rule_port_range_set(&rule->sport_range) && | |
324 | !fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport)) | |
325 | return 0; | |
326 | ||
327 | if (fib_rule_port_range_set(&rule->dport_range) && | |
328 | !fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport)) | |
329 | return 0; | |
330 | ||
101367c2 TG |
331 | return 1; |
332 | } | |
333 | ||
ef7c79ed | 334 | static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = { |
1f6c9557 | 335 | FRA_GENERIC_POLICY, |
101367c2 TG |
336 | }; |
337 | ||
338 | static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb, | |
8b3521ee | 339 | struct fib_rule_hdr *frh, |
b16fb418 RP |
340 | struct nlattr **tb, |
341 | struct netlink_ext_ack *extack) | |
101367c2 TG |
342 | { |
343 | int err = -EINVAL; | |
3b1e0a65 | 344 | struct net *net = sock_net(skb->sk); |
101367c2 TG |
345 | struct fib6_rule *rule6 = (struct fib6_rule *) rule; |
346 | ||
96c63fa7 | 347 | if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) { |
b16fb418 RP |
348 | if (rule->table == RT6_TABLE_UNSPEC) { |
349 | NL_SET_ERR_MSG(extack, "Invalid table"); | |
101367c2 | 350 | goto errout; |
b16fb418 | 351 | } |
101367c2 | 352 | |
dcabb819 | 353 | if (fib6_new_table(net, rule->table) == NULL) { |
101367c2 TG |
354 | err = -ENOBUFS; |
355 | goto errout; | |
356 | } | |
357 | } | |
358 | ||
e1701c68 | 359 | if (frh->src_len) |
67b61f6c | 360 | rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]); |
101367c2 | 361 | |
e1701c68 | 362 | if (frh->dst_len) |
67b61f6c | 363 | rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]); |
101367c2 TG |
364 | |
365 | rule6->src.plen = frh->src_len; | |
366 | rule6->dst.plen = frh->dst_len; | |
367 | rule6->tclass = frh->tos; | |
368 | ||
5e5d6fed RP |
369 | if (fib_rule_requires_fldissect(rule)) |
370 | net->ipv6.fib6_rules_require_fldissect++; | |
371 | ||
feca7d8c | 372 | net->ipv6.fib6_has_custom_rules = true; |
101367c2 TG |
373 | err = 0; |
374 | errout: | |
375 | return err; | |
376 | } | |
377 | ||
5e5d6fed RP |
378 | static int fib6_rule_delete(struct fib_rule *rule) |
379 | { | |
380 | struct net *net = rule->fr_net; | |
381 | ||
382 | if (net->ipv6.fib6_rules_require_fldissect && | |
383 | fib_rule_requires_fldissect(rule)) | |
384 | net->ipv6.fib6_rules_require_fldissect--; | |
385 | ||
386 | return 0; | |
387 | } | |
388 | ||
101367c2 TG |
389 | static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh, |
390 | struct nlattr **tb) | |
391 | { | |
392 | struct fib6_rule *rule6 = (struct fib6_rule *) rule; | |
393 | ||
394 | if (frh->src_len && (rule6->src.plen != frh->src_len)) | |
395 | return 0; | |
396 | ||
397 | if (frh->dst_len && (rule6->dst.plen != frh->dst_len)) | |
398 | return 0; | |
399 | ||
400 | if (frh->tos && (rule6->tclass != frh->tos)) | |
401 | return 0; | |
402 | ||
e1701c68 | 403 | if (frh->src_len && |
101367c2 TG |
404 | nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr))) |
405 | return 0; | |
406 | ||
e1701c68 | 407 | if (frh->dst_len && |
101367c2 TG |
408 | nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr))) |
409 | return 0; | |
410 | ||
411 | return 1; | |
412 | } | |
413 | ||
414 | static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb, | |
04af8cf6 | 415 | struct fib_rule_hdr *frh) |
101367c2 TG |
416 | { |
417 | struct fib6_rule *rule6 = (struct fib6_rule *) rule; | |
418 | ||
101367c2 TG |
419 | frh->dst_len = rule6->dst.plen; |
420 | frh->src_len = rule6->src.plen; | |
421 | frh->tos = rule6->tclass; | |
422 | ||
c78679e8 | 423 | if ((rule6->dst.plen && |
930345ea | 424 | nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) || |
c78679e8 | 425 | (rule6->src.plen && |
930345ea | 426 | nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr))) |
c78679e8 | 427 | goto nla_put_failure; |
101367c2 TG |
428 | return 0; |
429 | ||
430 | nla_put_failure: | |
431 | return -ENOBUFS; | |
432 | } | |
433 | ||
339bf98f TG |
434 | static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule) |
435 | { | |
436 | return nla_total_size(16) /* dst */ | |
437 | + nla_total_size(16); /* src */ | |
438 | } | |
439 | ||
04a6f82c | 440 | static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = { |
25239cee | 441 | .family = AF_INET6, |
101367c2 | 442 | .rule_size = sizeof(struct fib6_rule), |
e1701c68 | 443 | .addr_size = sizeof(struct in6_addr), |
101367c2 TG |
444 | .action = fib6_rule_action, |
445 | .match = fib6_rule_match, | |
7764a45a | 446 | .suppress = fib6_rule_suppress, |
101367c2 | 447 | .configure = fib6_rule_configure, |
5e5d6fed | 448 | .delete = fib6_rule_delete, |
101367c2 TG |
449 | .compare = fib6_rule_compare, |
450 | .fill = fib6_rule_fill, | |
339bf98f | 451 | .nlmsg_payload = fib6_rule_nlmsg_payload, |
101367c2 TG |
452 | .nlgroup = RTNLGRP_IPV6_RULE, |
453 | .policy = fib6_rule_policy, | |
101367c2 | 454 | .owner = THIS_MODULE, |
03592383 | 455 | .fro_net = &init_net, |
101367c2 TG |
456 | }; |
457 | ||
2c8c1e72 | 458 | static int __net_init fib6_rules_net_init(struct net *net) |
101367c2 | 459 | { |
e9c5158a | 460 | struct fib_rules_ops *ops; |
dcabb819 | 461 | int err = -ENOMEM; |
2994c638 | 462 | |
e9c5158a EB |
463 | ops = fib_rules_register(&fib6_rules_ops_template, net); |
464 | if (IS_ERR(ops)) | |
465 | return PTR_ERR(ops); | |
eb5564b8 | 466 | |
85b99092 | 467 | err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0); |
dcabb819 DL |
468 | if (err) |
469 | goto out_fib6_rules_ops; | |
9eb87f3f | 470 | |
85b99092 | 471 | err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0); |
dcabb819 | 472 | if (err) |
e9c5158a | 473 | goto out_fib6_rules_ops; |
9eb87f3f | 474 | |
85b99092 | 475 | net->ipv6.fib6_rules_ops = ops; |
5e5d6fed | 476 | net->ipv6.fib6_rules_require_fldissect = 0; |
9eb87f3f | 477 | out: |
dcabb819 | 478 | return err; |
9eb87f3f | 479 | |
dcabb819 | 480 | out_fib6_rules_ops: |
e9c5158a | 481 | fib_rules_unregister(ops); |
9eb87f3f | 482 | goto out; |
101367c2 TG |
483 | } |
484 | ||
2c8c1e72 | 485 | static void __net_exit fib6_rules_net_exit(struct net *net) |
dcabb819 | 486 | { |
419df12f | 487 | rtnl_lock(); |
dcabb819 | 488 | fib_rules_unregister(net->ipv6.fib6_rules_ops); |
419df12f | 489 | rtnl_unlock(); |
dcabb819 DL |
490 | } |
491 | ||
492 | static struct pernet_operations fib6_rules_net_ops = { | |
493 | .init = fib6_rules_net_init, | |
494 | .exit = fib6_rules_net_exit, | |
495 | }; | |
496 | ||
497 | int __init fib6_rules_init(void) | |
498 | { | |
499 | return register_pernet_subsys(&fib6_rules_net_ops); | |
500 | } | |
501 | ||
502 | ||
101367c2 TG |
503 | void fib6_rules_cleanup(void) |
504 | { | |
ff4e1fb0 | 505 | unregister_pernet_subsys(&fib6_rules_net_ops); |
101367c2 | 506 | } |