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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * net/ipv6/fib6_rules.c IPv6 Routing Policy Rules
4 *
5 * Copyright (C)2003-2006 Helsinki University of Technology
6 * Copyright (C)2003-2006 USAGI/WIDE Project
7 *
8 * Authors
9 * Thomas Graf <tgraf@suug.ch>
10 * Ville Nuorvala <vnuorval@tcs.hut.fi>
11 */
12
13#include <linux/netdevice.h>
14#include <linux/notifier.h>
15#include <linux/export.h>
16#include <linux/indirect_call_wrapper.h>
17
18#include <net/fib_rules.h>
19#include <net/inet_dscp.h>
20#include <net/ipv6.h>
21#include <net/addrconf.h>
22#include <net/ip6_route.h>
23#include <net/netlink.h>
24
25struct fib6_rule {
26 struct fib_rule common;
27 struct rt6key src;
28 struct rt6key dst;
29 dscp_t dscp;
30 u8 dscp_full:1; /* DSCP or TOS selector */
31};
32
33static 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->dscp)
38 return false;
39 return fib_rule_matchall(rule);
40}
41
42bool 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}
51EXPORT_SYMBOL_GPL(fib6_rule_default);
52
53int fib6_rules_dump(struct net *net, struct notifier_block *nb,
54 struct netlink_ext_ack *extack)
55{
56 return fib_rules_dump(net, nb, AF_INET6, extack);
57}
58
59unsigned int fib6_rules_seq_read(const struct net *net)
60{
61 return fib_rules_seq_read(net, AF_INET6);
62}
63
64/* called with rcu lock held; no reference taken on fib6_info */
65int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
66 struct fib6_result *res, int flags)
67{
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 .result = res,
75 .flags = FIB_LOOKUP_NOREF,
76 };
77
78 l3mdev_update_flow(net, flowi6_to_flowi(fl6));
79
80 err = fib_rules_lookup(net->ipv6.fib6_rules_ops,
81 flowi6_to_flowi(fl6), flags, &arg);
82 } else {
83 err = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, oif,
84 fl6, res, flags);
85 if (err || res->f6i == net->ipv6.fib6_null_entry)
86 err = fib6_table_lookup(net, net->ipv6.fib6_main_tbl,
87 oif, fl6, res, flags);
88 }
89
90 return err;
91}
92
93struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
94 const struct sk_buff *skb,
95 int flags, pol_lookup_t lookup)
96{
97 if (net->ipv6.fib6_has_custom_rules) {
98 struct fib6_result res = {};
99 struct fib_lookup_arg arg = {
100 .lookup_ptr = lookup,
101 .lookup_data = skb,
102 .result = &res,
103 .flags = FIB_LOOKUP_NOREF,
104 };
105
106 /* update flow if oif or iif point to device enslaved to l3mdev */
107 l3mdev_update_flow(net, flowi6_to_flowi(fl6));
108
109 fib_rules_lookup(net->ipv6.fib6_rules_ops,
110 flowi6_to_flowi(fl6), flags, &arg);
111
112 if (res.rt6)
113 return &res.rt6->dst;
114 } else {
115 struct rt6_info *rt;
116
117 rt = pol_lookup_func(lookup,
118 net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
119 if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
120 return &rt->dst;
121 ip6_rt_put_flags(rt, flags);
122 rt = pol_lookup_func(lookup,
123 net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
124 if (rt->dst.error != -EAGAIN)
125 return &rt->dst;
126 ip6_rt_put_flags(rt, flags);
127 }
128
129 if (!(flags & RT6_LOOKUP_F_DST_NOREF))
130 dst_hold(&net->ipv6.ip6_null_entry->dst);
131 return &net->ipv6.ip6_null_entry->dst;
132}
133
134static int fib6_rule_saddr(struct net *net, struct fib_rule *rule, int flags,
135 struct flowi6 *flp6, const struct net_device *dev)
136{
137 struct fib6_rule *r = (struct fib6_rule *)rule;
138
139 /* If we need to find a source address for this traffic,
140 * we check the result if it meets requirement of the rule.
141 */
142 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
143 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
144 struct in6_addr saddr;
145
146 if (ipv6_dev_get_saddr(net, dev, &flp6->daddr,
147 rt6_flags2srcprefs(flags), &saddr))
148 return -EAGAIN;
149
150 if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
151 return -EAGAIN;
152
153 flp6->saddr = saddr;
154 }
155
156 return 0;
157}
158
159static int fib6_rule_action_alt(struct fib_rule *rule, struct flowi *flp,
160 int flags, struct fib_lookup_arg *arg)
161{
162 struct fib6_result *res = arg->result;
163 struct flowi6 *flp6 = &flp->u.ip6;
164 struct net *net = rule->fr_net;
165 struct fib6_table *table;
166 int err, *oif;
167 u32 tb_id;
168
169 switch (rule->action) {
170 case FR_ACT_TO_TBL:
171 break;
172 case FR_ACT_UNREACHABLE:
173 return -ENETUNREACH;
174 case FR_ACT_PROHIBIT:
175 return -EACCES;
176 case FR_ACT_BLACKHOLE:
177 default:
178 return -EINVAL;
179 }
180
181 tb_id = fib_rule_get_table(rule, arg);
182 table = fib6_get_table(net, tb_id);
183 if (!table)
184 return -EAGAIN;
185
186 oif = (int *)arg->lookup_data;
187 err = fib6_table_lookup(net, table, *oif, flp6, res, flags);
188 if (!err && res->f6i != net->ipv6.fib6_null_entry)
189 err = fib6_rule_saddr(net, rule, flags, flp6,
190 res->nh->fib_nh_dev);
191 else
192 err = -EAGAIN;
193
194 return err;
195}
196
197static int __fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
198 int flags, struct fib_lookup_arg *arg)
199{
200 struct fib6_result *res = arg->result;
201 struct flowi6 *flp6 = &flp->u.ip6;
202 struct rt6_info *rt = NULL;
203 struct fib6_table *table;
204 struct net *net = rule->fr_net;
205 pol_lookup_t lookup = arg->lookup_ptr;
206 int err = 0;
207 u32 tb_id;
208
209 switch (rule->action) {
210 case FR_ACT_TO_TBL:
211 break;
212 case FR_ACT_UNREACHABLE:
213 err = -ENETUNREACH;
214 rt = net->ipv6.ip6_null_entry;
215 goto discard_pkt;
216 default:
217 case FR_ACT_BLACKHOLE:
218 err = -EINVAL;
219 rt = net->ipv6.ip6_blk_hole_entry;
220 goto discard_pkt;
221 case FR_ACT_PROHIBIT:
222 err = -EACCES;
223 rt = net->ipv6.ip6_prohibit_entry;
224 goto discard_pkt;
225 }
226
227 tb_id = fib_rule_get_table(rule, arg);
228 table = fib6_get_table(net, tb_id);
229 if (!table) {
230 err = -EAGAIN;
231 goto out;
232 }
233
234 rt = pol_lookup_func(lookup,
235 net, table, flp6, arg->lookup_data, flags);
236 if (rt != net->ipv6.ip6_null_entry) {
237 struct inet6_dev *idev = ip6_dst_idev(&rt->dst);
238
239 if (!idev)
240 goto again;
241 err = fib6_rule_saddr(net, rule, flags, flp6,
242 idev->dev);
243
244 if (err == -EAGAIN)
245 goto again;
246
247 err = rt->dst.error;
248 if (err != -EAGAIN)
249 goto out;
250 }
251again:
252 ip6_rt_put_flags(rt, flags);
253 err = -EAGAIN;
254 rt = NULL;
255 goto out;
256
257discard_pkt:
258 if (!(flags & RT6_LOOKUP_F_DST_NOREF))
259 dst_hold(&rt->dst);
260out:
261 res->rt6 = rt;
262 return err;
263}
264
265INDIRECT_CALLABLE_SCOPE int fib6_rule_action(struct fib_rule *rule,
266 struct flowi *flp, int flags,
267 struct fib_lookup_arg *arg)
268{
269 if (arg->lookup_ptr == fib6_table_lookup)
270 return fib6_rule_action_alt(rule, flp, flags, arg);
271
272 return __fib6_rule_action(rule, flp, flags, arg);
273}
274
275INDIRECT_CALLABLE_SCOPE bool fib6_rule_suppress(struct fib_rule *rule,
276 int flags,
277 struct fib_lookup_arg *arg)
278{
279 struct fib6_result *res = arg->result;
280 struct rt6_info *rt = res->rt6;
281 struct net_device *dev = NULL;
282
283 if (!rt)
284 return false;
285
286 if (rt->rt6i_idev)
287 dev = rt->rt6i_idev->dev;
288
289 /* do not accept result if the route does
290 * not meet the required prefix length
291 */
292 if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
293 goto suppress_route;
294
295 /* do not accept result if the route uses a device
296 * belonging to a forbidden interface group
297 */
298 if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
299 goto suppress_route;
300
301 return false;
302
303suppress_route:
304 ip6_rt_put_flags(rt, flags);
305 return true;
306}
307
308INDIRECT_CALLABLE_SCOPE int fib6_rule_match(struct fib_rule *rule,
309 struct flowi *fl, int flags)
310{
311 struct fib6_rule *r = (struct fib6_rule *) rule;
312 struct flowi6 *fl6 = &fl->u.ip6;
313
314 if (r->dst.plen &&
315 !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
316 return 0;
317
318 /*
319 * If FIB_RULE_FIND_SADDR is set and we do not have a
320 * source address for the traffic, we defer check for
321 * source address.
322 */
323 if (r->src.plen) {
324 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
325 if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
326 r->src.plen))
327 return 0;
328 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
329 return 0;
330 }
331
332 if (r->dscp && r->dscp != ip6_dscp(fl6->flowlabel))
333 return 0;
334
335 if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
336 return 0;
337
338 if (fib_rule_port_range_set(&rule->sport_range) &&
339 !fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport))
340 return 0;
341
342 if (fib_rule_port_range_set(&rule->dport_range) &&
343 !fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport))
344 return 0;
345
346 return 1;
347}
348
349static int fib6_nl2rule_dscp(const struct nlattr *nla, struct fib6_rule *rule6,
350 struct netlink_ext_ack *extack)
351{
352 if (rule6->dscp) {
353 NL_SET_ERR_MSG(extack, "Cannot specify both TOS and DSCP");
354 return -EINVAL;
355 }
356
357 rule6->dscp = inet_dsfield_to_dscp(nla_get_u8(nla) << 2);
358 rule6->dscp_full = true;
359
360 return 0;
361}
362
363static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
364 struct fib_rule_hdr *frh,
365 struct nlattr **tb,
366 struct netlink_ext_ack *extack)
367{
368 int err = -EINVAL;
369 struct net *net = sock_net(skb->sk);
370 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
371
372 if (!inet_validate_dscp(frh->tos)) {
373 NL_SET_ERR_MSG(extack,
374 "Invalid dsfield (tos): ECN bits must be 0");
375 goto errout;
376 }
377 rule6->dscp = inet_dsfield_to_dscp(frh->tos);
378
379 if (tb[FRA_DSCP] && fib6_nl2rule_dscp(tb[FRA_DSCP], rule6, extack) < 0)
380 goto errout;
381
382 if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
383 if (rule->table == RT6_TABLE_UNSPEC) {
384 NL_SET_ERR_MSG(extack, "Invalid table");
385 goto errout;
386 }
387
388 if (fib6_new_table(net, rule->table) == NULL) {
389 err = -ENOBUFS;
390 goto errout;
391 }
392 }
393
394 if (frh->src_len)
395 rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
396
397 if (frh->dst_len)
398 rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
399
400 rule6->src.plen = frh->src_len;
401 rule6->dst.plen = frh->dst_len;
402
403 if (fib_rule_requires_fldissect(rule))
404 net->ipv6.fib6_rules_require_fldissect++;
405
406 net->ipv6.fib6_has_custom_rules = true;
407 err = 0;
408errout:
409 return err;
410}
411
412static int fib6_rule_delete(struct fib_rule *rule)
413{
414 struct net *net = rule->fr_net;
415
416 if (net->ipv6.fib6_rules_require_fldissect &&
417 fib_rule_requires_fldissect(rule))
418 net->ipv6.fib6_rules_require_fldissect--;
419
420 return 0;
421}
422
423static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
424 struct nlattr **tb)
425{
426 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
427
428 if (frh->src_len && (rule6->src.plen != frh->src_len))
429 return 0;
430
431 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
432 return 0;
433
434 if (frh->tos &&
435 (rule6->dscp_full ||
436 inet_dscp_to_dsfield(rule6->dscp) != frh->tos))
437 return 0;
438
439 if (tb[FRA_DSCP]) {
440 dscp_t dscp;
441
442 dscp = inet_dsfield_to_dscp(nla_get_u8(tb[FRA_DSCP]) << 2);
443 if (!rule6->dscp_full || rule6->dscp != dscp)
444 return 0;
445 }
446
447 if (frh->src_len &&
448 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
449 return 0;
450
451 if (frh->dst_len &&
452 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
453 return 0;
454
455 return 1;
456}
457
458static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
459 struct fib_rule_hdr *frh)
460{
461 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
462
463 frh->dst_len = rule6->dst.plen;
464 frh->src_len = rule6->src.plen;
465
466 if (rule6->dscp_full) {
467 frh->tos = 0;
468 if (nla_put_u8(skb, FRA_DSCP,
469 inet_dscp_to_dsfield(rule6->dscp) >> 2))
470 goto nla_put_failure;
471 } else {
472 frh->tos = inet_dscp_to_dsfield(rule6->dscp);
473 }
474
475 if ((rule6->dst.plen &&
476 nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) ||
477 (rule6->src.plen &&
478 nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
479 goto nla_put_failure;
480 return 0;
481
482nla_put_failure:
483 return -ENOBUFS;
484}
485
486static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
487{
488 return nla_total_size(16) /* dst */
489 + nla_total_size(16) /* src */
490 + nla_total_size(1); /* dscp */
491}
492
493static void fib6_rule_flush_cache(struct fib_rules_ops *ops)
494{
495 rt_genid_bump_ipv6(ops->fro_net);
496}
497
498static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
499 .family = AF_INET6,
500 .rule_size = sizeof(struct fib6_rule),
501 .addr_size = sizeof(struct in6_addr),
502 .action = fib6_rule_action,
503 .match = fib6_rule_match,
504 .suppress = fib6_rule_suppress,
505 .configure = fib6_rule_configure,
506 .delete = fib6_rule_delete,
507 .compare = fib6_rule_compare,
508 .fill = fib6_rule_fill,
509 .nlmsg_payload = fib6_rule_nlmsg_payload,
510 .flush_cache = fib6_rule_flush_cache,
511 .nlgroup = RTNLGRP_IPV6_RULE,
512 .owner = THIS_MODULE,
513 .fro_net = &init_net,
514};
515
516static int __net_init fib6_rules_net_init(struct net *net)
517{
518 struct fib_rules_ops *ops;
519 int err;
520
521 ops = fib_rules_register(&fib6_rules_ops_template, net);
522 if (IS_ERR(ops))
523 return PTR_ERR(ops);
524
525 err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL);
526 if (err)
527 goto out_fib6_rules_ops;
528
529 err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN);
530 if (err)
531 goto out_fib6_rules_ops;
532
533 net->ipv6.fib6_rules_ops = ops;
534 net->ipv6.fib6_rules_require_fldissect = 0;
535out:
536 return err;
537
538out_fib6_rules_ops:
539 fib_rules_unregister(ops);
540 goto out;
541}
542
543static void __net_exit fib6_rules_net_exit_batch(struct list_head *net_list)
544{
545 struct net *net;
546
547 rtnl_lock();
548 list_for_each_entry(net, net_list, exit_list) {
549 fib_rules_unregister(net->ipv6.fib6_rules_ops);
550 cond_resched();
551 }
552 rtnl_unlock();
553}
554
555static struct pernet_operations fib6_rules_net_ops = {
556 .init = fib6_rules_net_init,
557 .exit_batch = fib6_rules_net_exit_batch,
558};
559
560int __init fib6_rules_init(void)
561{
562 return register_pernet_subsys(&fib6_rules_net_ops);
563}
564
565
566void fib6_rules_cleanup(void)
567{
568 unregister_pernet_subsys(&fib6_rules_net_ops);
569}
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
16#include <linux/netdevice.h>
17#include <linux/notifier.h>
18#include <linux/export.h>
19
20#include <net/fib_rules.h>
21#include <net/ipv6.h>
22#include <net/addrconf.h>
23#include <net/ip6_route.h>
24#include <net/netlink.h>
25
26struct fib6_rule {
27 struct fib_rule common;
28 struct rt6key src;
29 struct rt6key dst;
30 u8 tclass;
31};
32
33static 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
42bool 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}
51EXPORT_SYMBOL_GPL(fib6_rule_default);
52
53int fib6_rules_dump(struct net *net, struct notifier_block *nb)
54{
55 return fib_rules_dump(net, nb, AF_INET6);
56}
57
58unsigned int fib6_rules_seq_read(struct net *net)
59{
60 return fib_rules_seq_read(net, AF_INET6);
61}
62
63struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
64 const struct sk_buff *skb,
65 int flags, pol_lookup_t lookup)
66{
67 if (net->ipv6.fib6_has_custom_rules) {
68 struct fib_lookup_arg arg = {
69 .lookup_ptr = lookup,
70 .lookup_data = skb,
71 .flags = FIB_LOOKUP_NOREF,
72 };
73
74 /* update flow if oif or iif point to device enslaved to l3mdev */
75 l3mdev_update_flow(net, flowi6_to_flowi(fl6));
76
77 fib_rules_lookup(net->ipv6.fib6_rules_ops,
78 flowi6_to_flowi(fl6), flags, &arg);
79
80 if (arg.result)
81 return arg.result;
82 } else {
83 struct rt6_info *rt;
84
85 rt = lookup(net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
86 if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
87 return &rt->dst;
88 ip6_rt_put(rt);
89 rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
90 if (rt->dst.error != -EAGAIN)
91 return &rt->dst;
92 ip6_rt_put(rt);
93 }
94
95 dst_hold(&net->ipv6.ip6_null_entry->dst);
96 return &net->ipv6.ip6_null_entry->dst;
97}
98
99static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
100 int flags, struct fib_lookup_arg *arg)
101{
102 struct flowi6 *flp6 = &flp->u.ip6;
103 struct rt6_info *rt = NULL;
104 struct fib6_table *table;
105 struct net *net = rule->fr_net;
106 pol_lookup_t lookup = arg->lookup_ptr;
107 int err = 0;
108 u32 tb_id;
109
110 switch (rule->action) {
111 case FR_ACT_TO_TBL:
112 break;
113 case FR_ACT_UNREACHABLE:
114 err = -ENETUNREACH;
115 rt = net->ipv6.ip6_null_entry;
116 goto discard_pkt;
117 default:
118 case FR_ACT_BLACKHOLE:
119 err = -EINVAL;
120 rt = net->ipv6.ip6_blk_hole_entry;
121 goto discard_pkt;
122 case FR_ACT_PROHIBIT:
123 err = -EACCES;
124 rt = net->ipv6.ip6_prohibit_entry;
125 goto discard_pkt;
126 }
127
128 tb_id = fib_rule_get_table(rule, arg);
129 table = fib6_get_table(net, tb_id);
130 if (!table) {
131 err = -EAGAIN;
132 goto out;
133 }
134
135 rt = lookup(net, table, flp6, arg->lookup_data, flags);
136 if (rt != net->ipv6.ip6_null_entry) {
137 struct fib6_rule *r = (struct fib6_rule *)rule;
138
139 /*
140 * If we need to find a source address for this traffic,
141 * we check the result if it meets requirement of the rule.
142 */
143 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
144 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
145 struct in6_addr saddr;
146
147 if (ipv6_dev_get_saddr(net,
148 ip6_dst_idev(&rt->dst)->dev,
149 &flp6->daddr,
150 rt6_flags2srcprefs(flags),
151 &saddr))
152 goto again;
153 if (!ipv6_prefix_equal(&saddr, &r->src.addr,
154 r->src.plen))
155 goto again;
156 flp6->saddr = saddr;
157 }
158 err = rt->dst.error;
159 if (err != -EAGAIN)
160 goto out;
161 }
162again:
163 ip6_rt_put(rt);
164 err = -EAGAIN;
165 rt = NULL;
166 goto out;
167
168discard_pkt:
169 dst_hold(&rt->dst);
170out:
171 arg->result = rt;
172 return err;
173}
174
175static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
176{
177 struct rt6_info *rt = (struct rt6_info *) arg->result;
178 struct net_device *dev = NULL;
179
180 if (rt->rt6i_idev)
181 dev = rt->rt6i_idev->dev;
182
183 /* do not accept result if the route does
184 * not meet the required prefix length
185 */
186 if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
187 goto suppress_route;
188
189 /* do not accept result if the route uses a device
190 * belonging to a forbidden interface group
191 */
192 if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
193 goto suppress_route;
194
195 return false;
196
197suppress_route:
198 ip6_rt_put(rt);
199 return true;
200}
201
202static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
203{
204 struct fib6_rule *r = (struct fib6_rule *) rule;
205 struct flowi6 *fl6 = &fl->u.ip6;
206
207 if (r->dst.plen &&
208 !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
209 return 0;
210
211 /*
212 * If FIB_RULE_FIND_SADDR is set and we do not have a
213 * source address for the traffic, we defer check for
214 * source address.
215 */
216 if (r->src.plen) {
217 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
218 if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
219 r->src.plen))
220 return 0;
221 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
222 return 0;
223 }
224
225 if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel))
226 return 0;
227
228 if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
229 return 0;
230
231 if (fib_rule_port_range_set(&rule->sport_range) &&
232 !fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport))
233 return 0;
234
235 if (fib_rule_port_range_set(&rule->dport_range) &&
236 !fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport))
237 return 0;
238
239 return 1;
240}
241
242static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
243 FRA_GENERIC_POLICY,
244};
245
246static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
247 struct fib_rule_hdr *frh,
248 struct nlattr **tb)
249{
250 int err = -EINVAL;
251 struct net *net = sock_net(skb->sk);
252 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
253
254 if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
255 if (rule->table == RT6_TABLE_UNSPEC)
256 goto errout;
257
258 if (fib6_new_table(net, rule->table) == NULL) {
259 err = -ENOBUFS;
260 goto errout;
261 }
262 }
263
264 if (frh->src_len)
265 rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
266
267 if (frh->dst_len)
268 rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
269
270 rule6->src.plen = frh->src_len;
271 rule6->dst.plen = frh->dst_len;
272 rule6->tclass = frh->tos;
273
274 if (fib_rule_requires_fldissect(rule))
275 net->ipv6.fib6_rules_require_fldissect++;
276
277 net->ipv6.fib6_has_custom_rules = true;
278 err = 0;
279errout:
280 return err;
281}
282
283static int fib6_rule_delete(struct fib_rule *rule)
284{
285 struct net *net = rule->fr_net;
286
287 if (net->ipv6.fib6_rules_require_fldissect &&
288 fib_rule_requires_fldissect(rule))
289 net->ipv6.fib6_rules_require_fldissect--;
290
291 return 0;
292}
293
294static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
295 struct nlattr **tb)
296{
297 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
298
299 if (frh->src_len && (rule6->src.plen != frh->src_len))
300 return 0;
301
302 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
303 return 0;
304
305 if (frh->tos && (rule6->tclass != frh->tos))
306 return 0;
307
308 if (frh->src_len &&
309 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
310 return 0;
311
312 if (frh->dst_len &&
313 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
314 return 0;
315
316 return 1;
317}
318
319static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
320 struct fib_rule_hdr *frh)
321{
322 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
323
324 frh->dst_len = rule6->dst.plen;
325 frh->src_len = rule6->src.plen;
326 frh->tos = rule6->tclass;
327
328 if ((rule6->dst.plen &&
329 nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) ||
330 (rule6->src.plen &&
331 nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
332 goto nla_put_failure;
333 return 0;
334
335nla_put_failure:
336 return -ENOBUFS;
337}
338
339static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
340{
341 return nla_total_size(16) /* dst */
342 + nla_total_size(16); /* src */
343}
344
345static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
346 .family = AF_INET6,
347 .rule_size = sizeof(struct fib6_rule),
348 .addr_size = sizeof(struct in6_addr),
349 .action = fib6_rule_action,
350 .match = fib6_rule_match,
351 .suppress = fib6_rule_suppress,
352 .configure = fib6_rule_configure,
353 .delete = fib6_rule_delete,
354 .compare = fib6_rule_compare,
355 .fill = fib6_rule_fill,
356 .nlmsg_payload = fib6_rule_nlmsg_payload,
357 .nlgroup = RTNLGRP_IPV6_RULE,
358 .policy = fib6_rule_policy,
359 .owner = THIS_MODULE,
360 .fro_net = &init_net,
361};
362
363static int __net_init fib6_rules_net_init(struct net *net)
364{
365 struct fib_rules_ops *ops;
366 int err = -ENOMEM;
367
368 ops = fib_rules_register(&fib6_rules_ops_template, net);
369 if (IS_ERR(ops))
370 return PTR_ERR(ops);
371
372 err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0);
373 if (err)
374 goto out_fib6_rules_ops;
375
376 err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0);
377 if (err)
378 goto out_fib6_rules_ops;
379
380 net->ipv6.fib6_rules_ops = ops;
381 net->ipv6.fib6_rules_require_fldissect = 0;
382out:
383 return err;
384
385out_fib6_rules_ops:
386 fib_rules_unregister(ops);
387 goto out;
388}
389
390static void __net_exit fib6_rules_net_exit(struct net *net)
391{
392 rtnl_lock();
393 fib_rules_unregister(net->ipv6.fib6_rules_ops);
394 rtnl_unlock();
395}
396
397static struct pernet_operations fib6_rules_net_ops = {
398 .init = fib6_rules_net_init,
399 .exit = fib6_rules_net_exit,
400};
401
402int __init fib6_rules_init(void)
403{
404 return register_pernet_subsys(&fib6_rules_net_ops);
405}
406
407
408void fib6_rules_cleanup(void)
409{
410 unregister_pernet_subsys(&fib6_rules_net_ops);
411}