1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * net/core/fib_rules.c Generic Routing Rules |
4 | * |
5 | * Authors: Thomas Graf <tgraf@suug.ch> |
6 | */ |
7 | |
8 | #include <linux/types.h> |
9 | #include <linux/kernel.h> |
10 | #include <linux/slab.h> |
11 | #include <linux/list.h> |
12 | #include <linux/module.h> |
13 | #include <net/net_namespace.h> |
14 | #include <net/sock.h> |
15 | #include <net/fib_rules.h> |
16 | #include <net/ip_tunnels.h> |
17 | #include <linux/indirect_call_wrapper.h> |
18 | |
19 | #if defined(CONFIG_IPV6) && defined(CONFIG_IPV6_MULTIPLE_TABLES) |
20 | #ifdef CONFIG_IP_MULTIPLE_TABLES |
21 | #define INDIRECT_CALL_MT(f, f2, f1, ...) \ |
22 | INDIRECT_CALL_INET(f, f2, f1, __VA_ARGS__) |
23 | #else |
24 | #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__) |
25 | #endif |
26 | #elif defined(CONFIG_IP_MULTIPLE_TABLES) |
27 | #define INDIRECT_CALL_MT(f, f2, f1, ...) INDIRECT_CALL_1(f, f1, __VA_ARGS__) |
28 | #else |
29 | #define INDIRECT_CALL_MT(f, f2, f1, ...) f(__VA_ARGS__) |
30 | #endif |
31 | |
32 | static const struct fib_kuid_range fib_kuid_range_unset = { |
33 | KUIDT_INIT(0), |
34 | KUIDT_INIT(~0), |
35 | }; |
36 | |
37 | bool fib_rule_matchall(const struct fib_rule *rule) |
38 | { |
39 | if (rule->iifindex || rule->oifindex || rule->mark || rule->tun_id || |
40 | rule->flags) |
41 | return false; |
42 | if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1) |
43 | return false; |
44 | if (!uid_eq(left: rule->uid_range.start, right: fib_kuid_range_unset.start) || |
45 | !uid_eq(left: rule->uid_range.end, right: fib_kuid_range_unset.end)) |
46 | return false; |
47 | if (fib_rule_port_range_set(range: &rule->sport_range)) |
48 | return false; |
49 | if (fib_rule_port_range_set(range: &rule->dport_range)) |
50 | return false; |
51 | return true; |
52 | } |
53 | EXPORT_SYMBOL_GPL(fib_rule_matchall); |
54 | |
55 | int fib_default_rule_add(struct fib_rules_ops *ops, |
56 | u32 pref, u32 table) |
57 | { |
58 | struct fib_rule *r; |
59 | |
60 | r = kzalloc(size: ops->rule_size, GFP_KERNEL_ACCOUNT); |
61 | if (r == NULL) |
62 | return -ENOMEM; |
63 | |
64 | refcount_set(r: &r->refcnt, n: 1); |
65 | r->action = FR_ACT_TO_TBL; |
66 | r->pref = pref; |
67 | r->table = table; |
68 | r->proto = RTPROT_KERNEL; |
69 | r->fr_net = ops->fro_net; |
70 | r->uid_range = fib_kuid_range_unset; |
71 | |
72 | r->suppress_prefixlen = -1; |
73 | r->suppress_ifgroup = -1; |
74 | |
75 | /* The lock is not required here, the list in unreacheable |
76 | * at the moment this function is called */ |
77 | list_add_tail(new: &r->list, head: &ops->rules_list); |
78 | return 0; |
79 | } |
80 | EXPORT_SYMBOL(fib_default_rule_add); |
81 | |
82 | static u32 fib_default_rule_pref(struct fib_rules_ops *ops) |
83 | { |
84 | struct list_head *pos; |
85 | struct fib_rule *rule; |
86 | |
87 | if (!list_empty(head: &ops->rules_list)) { |
88 | pos = ops->rules_list.next; |
89 | if (pos->next != &ops->rules_list) { |
90 | rule = list_entry(pos->next, struct fib_rule, list); |
91 | if (rule->pref) |
92 | return rule->pref - 1; |
93 | } |
94 | } |
95 | |
96 | return 0; |
97 | } |
98 | |
99 | static void notify_rule_change(int event, struct fib_rule *rule, |
100 | struct fib_rules_ops *ops, struct nlmsghdr *nlh, |
101 | u32 pid); |
102 | |
103 | static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family) |
104 | { |
105 | struct fib_rules_ops *ops; |
106 | |
107 | rcu_read_lock(); |
108 | list_for_each_entry_rcu(ops, &net->rules_ops, list) { |
109 | if (ops->family == family) { |
110 | if (!try_module_get(module: ops->owner)) |
111 | ops = NULL; |
112 | rcu_read_unlock(); |
113 | return ops; |
114 | } |
115 | } |
116 | rcu_read_unlock(); |
117 | |
118 | return NULL; |
119 | } |
120 | |
121 | static void rules_ops_put(struct fib_rules_ops *ops) |
122 | { |
123 | if (ops) |
124 | module_put(module: ops->owner); |
125 | } |
126 | |
127 | static void flush_route_cache(struct fib_rules_ops *ops) |
128 | { |
129 | if (ops->flush_cache) |
130 | ops->flush_cache(ops); |
131 | } |
132 | |
133 | static int __fib_rules_register(struct fib_rules_ops *ops) |
134 | { |
135 | int err = -EEXIST; |
136 | struct fib_rules_ops *o; |
137 | struct net *net; |
138 | |
139 | net = ops->fro_net; |
140 | |
141 | if (ops->rule_size < sizeof(struct fib_rule)) |
142 | return -EINVAL; |
143 | |
144 | if (ops->match == NULL || ops->configure == NULL || |
145 | ops->compare == NULL || ops->fill == NULL || |
146 | ops->action == NULL) |
147 | return -EINVAL; |
148 | |
149 | spin_lock(lock: &net->rules_mod_lock); |
150 | list_for_each_entry(o, &net->rules_ops, list) |
151 | if (ops->family == o->family) |
152 | goto errout; |
153 | |
154 | list_add_tail_rcu(new: &ops->list, head: &net->rules_ops); |
155 | err = 0; |
156 | errout: |
157 | spin_unlock(lock: &net->rules_mod_lock); |
158 | |
159 | return err; |
160 | } |
161 | |
162 | struct fib_rules_ops * |
163 | fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net) |
164 | { |
165 | struct fib_rules_ops *ops; |
166 | int err; |
167 | |
168 | ops = kmemdup(p: tmpl, size: sizeof(*ops), GFP_KERNEL); |
169 | if (ops == NULL) |
170 | return ERR_PTR(error: -ENOMEM); |
171 | |
172 | INIT_LIST_HEAD(list: &ops->rules_list); |
173 | ops->fro_net = net; |
174 | |
175 | err = __fib_rules_register(ops); |
176 | if (err) { |
177 | kfree(objp: ops); |
178 | ops = ERR_PTR(error: err); |
179 | } |
180 | |
181 | return ops; |
182 | } |
183 | EXPORT_SYMBOL_GPL(fib_rules_register); |
184 | |
185 | static void fib_rules_cleanup_ops(struct fib_rules_ops *ops) |
186 | { |
187 | struct fib_rule *rule, *tmp; |
188 | |
189 | list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) { |
190 | list_del_rcu(entry: &rule->list); |
191 | if (ops->delete) |
192 | ops->delete(rule); |
193 | fib_rule_put(rule); |
194 | } |
195 | } |
196 | |
197 | void fib_rules_unregister(struct fib_rules_ops *ops) |
198 | { |
199 | struct net *net = ops->fro_net; |
200 | |
201 | spin_lock(lock: &net->rules_mod_lock); |
202 | list_del_rcu(entry: &ops->list); |
203 | spin_unlock(lock: &net->rules_mod_lock); |
204 | |
205 | fib_rules_cleanup_ops(ops); |
206 | kfree_rcu(ops, rcu); |
207 | } |
208 | EXPORT_SYMBOL_GPL(fib_rules_unregister); |
209 | |
210 | static int uid_range_set(struct fib_kuid_range *range) |
211 | { |
212 | return uid_valid(uid: range->start) && uid_valid(uid: range->end); |
213 | } |
214 | |
215 | static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb) |
216 | { |
217 | struct fib_rule_uid_range *in; |
218 | struct fib_kuid_range out; |
219 | |
220 | in = (struct fib_rule_uid_range *)nla_data(nla: tb[FRA_UID_RANGE]); |
221 | |
222 | out.start = make_kuid(current_user_ns(), uid: in->start); |
223 | out.end = make_kuid(current_user_ns(), uid: in->end); |
224 | |
225 | return out; |
226 | } |
227 | |
228 | static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range) |
229 | { |
230 | struct fib_rule_uid_range out = { |
231 | from_kuid_munged(current_user_ns(), uid: range->start), |
232 | from_kuid_munged(current_user_ns(), uid: range->end) |
233 | }; |
234 | |
235 | return nla_put(skb, attrtype: FRA_UID_RANGE, attrlen: sizeof(out), data: &out); |
236 | } |
237 | |
238 | static int nla_get_port_range(struct nlattr *pattr, |
239 | struct fib_rule_port_range *port_range) |
240 | { |
241 | const struct fib_rule_port_range *pr = nla_data(nla: pattr); |
242 | |
243 | if (!fib_rule_port_range_valid(a: pr)) |
244 | return -EINVAL; |
245 | |
246 | port_range->start = pr->start; |
247 | port_range->end = pr->end; |
248 | |
249 | return 0; |
250 | } |
251 | |
252 | static int nla_put_port_range(struct sk_buff *skb, int attrtype, |
253 | struct fib_rule_port_range *range) |
254 | { |
255 | return nla_put(skb, attrtype, attrlen: sizeof(*range), data: range); |
256 | } |
257 | |
258 | static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops, |
259 | struct flowi *fl, int flags, |
260 | struct fib_lookup_arg *arg) |
261 | { |
262 | int ret = 0; |
263 | |
264 | if (rule->iifindex && (rule->iifindex != fl->flowi_iif)) |
265 | goto out; |
266 | |
267 | if (rule->oifindex && (rule->oifindex != fl->flowi_oif)) |
268 | goto out; |
269 | |
270 | if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask) |
271 | goto out; |
272 | |
273 | if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id)) |
274 | goto out; |
275 | |
276 | if (rule->l3mdev && !l3mdev_fib_rule_match(net: rule->fr_net, fl, arg)) |
277 | goto out; |
278 | |
279 | if (uid_lt(left: fl->flowi_uid, right: rule->uid_range.start) || |
280 | uid_gt(left: fl->flowi_uid, right: rule->uid_range.end)) |
281 | goto out; |
282 | |
283 | ret = INDIRECT_CALL_MT(ops->match, |
284 | fib6_rule_match, |
285 | fib4_rule_match, |
286 | rule, fl, flags); |
287 | out: |
288 | return (rule->flags & FIB_RULE_INVERT) ? !ret : ret; |
289 | } |
290 | |
291 | int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl, |
292 | int flags, struct fib_lookup_arg *arg) |
293 | { |
294 | struct fib_rule *rule; |
295 | int err; |
296 | |
297 | rcu_read_lock(); |
298 | |
299 | list_for_each_entry_rcu(rule, &ops->rules_list, list) { |
300 | jumped: |
301 | if (!fib_rule_match(rule, ops, fl, flags, arg)) |
302 | continue; |
303 | |
304 | if (rule->action == FR_ACT_GOTO) { |
305 | struct fib_rule *target; |
306 | |
307 | target = rcu_dereference(rule->ctarget); |
308 | if (target == NULL) { |
309 | continue; |
310 | } else { |
311 | rule = target; |
312 | goto jumped; |
313 | } |
314 | } else if (rule->action == FR_ACT_NOP) |
315 | continue; |
316 | else |
317 | err = INDIRECT_CALL_MT(ops->action, |
318 | fib6_rule_action, |
319 | fib4_rule_action, |
320 | rule, fl, flags, arg); |
321 | |
322 | if (!err && ops->suppress && INDIRECT_CALL_MT(ops->suppress, |
323 | fib6_rule_suppress, |
324 | fib4_rule_suppress, |
325 | rule, flags, arg)) |
326 | continue; |
327 | |
328 | if (err != -EAGAIN) { |
329 | if ((arg->flags & FIB_LOOKUP_NOREF) || |
330 | likely(refcount_inc_not_zero(&rule->refcnt))) { |
331 | arg->rule = rule; |
332 | goto out; |
333 | } |
334 | break; |
335 | } |
336 | } |
337 | |
338 | err = -ESRCH; |
339 | out: |
340 | rcu_read_unlock(); |
341 | |
342 | return err; |
343 | } |
344 | EXPORT_SYMBOL_GPL(fib_rules_lookup); |
345 | |
346 | static int call_fib_rule_notifier(struct notifier_block *nb, |
347 | enum fib_event_type event_type, |
348 | struct fib_rule *rule, int family, |
349 | struct netlink_ext_ack *extack) |
350 | { |
351 | struct fib_rule_notifier_info info = { |
352 | .info.family = family, |
353 | .info.extack = extack, |
354 | .rule = rule, |
355 | }; |
356 | |
357 | return call_fib_notifier(nb, event_type, info: &info.info); |
358 | } |
359 | |
360 | static int call_fib_rule_notifiers(struct net *net, |
361 | enum fib_event_type event_type, |
362 | struct fib_rule *rule, |
363 | struct fib_rules_ops *ops, |
364 | struct netlink_ext_ack *extack) |
365 | { |
366 | struct fib_rule_notifier_info info = { |
367 | .info.family = ops->family, |
368 | .info.extack = extack, |
369 | .rule = rule, |
370 | }; |
371 | |
372 | ops->fib_rules_seq++; |
373 | return call_fib_notifiers(net, event_type, info: &info.info); |
374 | } |
375 | |
376 | /* Called with rcu_read_lock() */ |
377 | int fib_rules_dump(struct net *net, struct notifier_block *nb, int family, |
378 | struct netlink_ext_ack *extack) |
379 | { |
380 | struct fib_rules_ops *ops; |
381 | struct fib_rule *rule; |
382 | int err = 0; |
383 | |
384 | ops = lookup_rules_ops(net, family); |
385 | if (!ops) |
386 | return -EAFNOSUPPORT; |
387 | list_for_each_entry_rcu(rule, &ops->rules_list, list) { |
388 | err = call_fib_rule_notifier(nb, event_type: FIB_EVENT_RULE_ADD, |
389 | rule, family, extack); |
390 | if (err) |
391 | break; |
392 | } |
393 | rules_ops_put(ops); |
394 | |
395 | return err; |
396 | } |
397 | EXPORT_SYMBOL_GPL(fib_rules_dump); |
398 | |
399 | unsigned int fib_rules_seq_read(struct net *net, int family) |
400 | { |
401 | unsigned int fib_rules_seq; |
402 | struct fib_rules_ops *ops; |
403 | |
404 | ASSERT_RTNL(); |
405 | |
406 | ops = lookup_rules_ops(net, family); |
407 | if (!ops) |
408 | return 0; |
409 | fib_rules_seq = ops->fib_rules_seq; |
410 | rules_ops_put(ops); |
411 | |
412 | return fib_rules_seq; |
413 | } |
414 | EXPORT_SYMBOL_GPL(fib_rules_seq_read); |
415 | |
416 | static struct fib_rule *rule_find(struct fib_rules_ops *ops, |
417 | struct fib_rule_hdr *frh, |
418 | struct nlattr **tb, |
419 | struct fib_rule *rule, |
420 | bool user_priority) |
421 | { |
422 | struct fib_rule *r; |
423 | |
424 | list_for_each_entry(r, &ops->rules_list, list) { |
425 | if (rule->action && r->action != rule->action) |
426 | continue; |
427 | |
428 | if (rule->table && r->table != rule->table) |
429 | continue; |
430 | |
431 | if (user_priority && r->pref != rule->pref) |
432 | continue; |
433 | |
434 | if (rule->iifname[0] && |
435 | memcmp(p: r->iifname, q: rule->iifname, IFNAMSIZ)) |
436 | continue; |
437 | |
438 | if (rule->oifname[0] && |
439 | memcmp(p: r->oifname, q: rule->oifname, IFNAMSIZ)) |
440 | continue; |
441 | |
442 | if (rule->mark && r->mark != rule->mark) |
443 | continue; |
444 | |
445 | if (rule->suppress_ifgroup != -1 && |
446 | r->suppress_ifgroup != rule->suppress_ifgroup) |
447 | continue; |
448 | |
449 | if (rule->suppress_prefixlen != -1 && |
450 | r->suppress_prefixlen != rule->suppress_prefixlen) |
451 | continue; |
452 | |
453 | if (rule->mark_mask && r->mark_mask != rule->mark_mask) |
454 | continue; |
455 | |
456 | if (rule->tun_id && r->tun_id != rule->tun_id) |
457 | continue; |
458 | |
459 | if (r->fr_net != rule->fr_net) |
460 | continue; |
461 | |
462 | if (rule->l3mdev && r->l3mdev != rule->l3mdev) |
463 | continue; |
464 | |
465 | if (uid_range_set(range: &rule->uid_range) && |
466 | (!uid_eq(left: r->uid_range.start, right: rule->uid_range.start) || |
467 | !uid_eq(left: r->uid_range.end, right: rule->uid_range.end))) |
468 | continue; |
469 | |
470 | if (rule->ip_proto && r->ip_proto != rule->ip_proto) |
471 | continue; |
472 | |
473 | if (rule->proto && r->proto != rule->proto) |
474 | continue; |
475 | |
476 | if (fib_rule_port_range_set(range: &rule->sport_range) && |
477 | !fib_rule_port_range_compare(a: &r->sport_range, |
478 | b: &rule->sport_range)) |
479 | continue; |
480 | |
481 | if (fib_rule_port_range_set(range: &rule->dport_range) && |
482 | !fib_rule_port_range_compare(a: &r->dport_range, |
483 | b: &rule->dport_range)) |
484 | continue; |
485 | |
486 | if (!ops->compare(r, frh, tb)) |
487 | continue; |
488 | return r; |
489 | } |
490 | |
491 | return NULL; |
492 | } |
493 | |
494 | #ifdef CONFIG_NET_L3_MASTER_DEV |
495 | static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule, |
496 | struct netlink_ext_ack *extack) |
497 | { |
498 | nlrule->l3mdev = nla_get_u8(nla); |
499 | if (nlrule->l3mdev != 1) { |
500 | NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute" ); |
501 | return -1; |
502 | } |
503 | |
504 | return 0; |
505 | } |
506 | #else |
507 | static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule, |
508 | struct netlink_ext_ack *extack) |
509 | { |
510 | NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel" ); |
511 | return -1; |
512 | } |
513 | #endif |
514 | |
515 | static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh, |
516 | struct netlink_ext_ack *extack, |
517 | struct fib_rules_ops *ops, |
518 | struct nlattr *tb[], |
519 | struct fib_rule **rule, |
520 | bool *user_priority) |
521 | { |
522 | struct net *net = sock_net(sk: skb->sk); |
523 | struct fib_rule_hdr *frh = nlmsg_data(nlh); |
524 | struct fib_rule *nlrule = NULL; |
525 | int err = -EINVAL; |
526 | |
527 | if (frh->src_len) |
528 | if (!tb[FRA_SRC] || |
529 | frh->src_len > (ops->addr_size * 8) || |
530 | nla_len(nla: tb[FRA_SRC]) != ops->addr_size) { |
531 | NL_SET_ERR_MSG(extack, "Invalid source address" ); |
532 | goto errout; |
533 | } |
534 | |
535 | if (frh->dst_len) |
536 | if (!tb[FRA_DST] || |
537 | frh->dst_len > (ops->addr_size * 8) || |
538 | nla_len(nla: tb[FRA_DST]) != ops->addr_size) { |
539 | NL_SET_ERR_MSG(extack, "Invalid dst address" ); |
540 | goto errout; |
541 | } |
542 | |
543 | nlrule = kzalloc(size: ops->rule_size, GFP_KERNEL_ACCOUNT); |
544 | if (!nlrule) { |
545 | err = -ENOMEM; |
546 | goto errout; |
547 | } |
548 | refcount_set(r: &nlrule->refcnt, n: 1); |
549 | nlrule->fr_net = net; |
550 | |
551 | if (tb[FRA_PRIORITY]) { |
552 | nlrule->pref = nla_get_u32(nla: tb[FRA_PRIORITY]); |
553 | *user_priority = true; |
554 | } else { |
555 | nlrule->pref = fib_default_rule_pref(ops); |
556 | } |
557 | |
558 | nlrule->proto = tb[FRA_PROTOCOL] ? |
559 | nla_get_u8(nla: tb[FRA_PROTOCOL]) : RTPROT_UNSPEC; |
560 | |
561 | if (tb[FRA_IIFNAME]) { |
562 | struct net_device *dev; |
563 | |
564 | nlrule->iifindex = -1; |
565 | nla_strscpy(dst: nlrule->iifname, nla: tb[FRA_IIFNAME], IFNAMSIZ); |
566 | dev = __dev_get_by_name(net, name: nlrule->iifname); |
567 | if (dev) |
568 | nlrule->iifindex = dev->ifindex; |
569 | } |
570 | |
571 | if (tb[FRA_OIFNAME]) { |
572 | struct net_device *dev; |
573 | |
574 | nlrule->oifindex = -1; |
575 | nla_strscpy(dst: nlrule->oifname, nla: tb[FRA_OIFNAME], IFNAMSIZ); |
576 | dev = __dev_get_by_name(net, name: nlrule->oifname); |
577 | if (dev) |
578 | nlrule->oifindex = dev->ifindex; |
579 | } |
580 | |
581 | if (tb[FRA_FWMARK]) { |
582 | nlrule->mark = nla_get_u32(nla: tb[FRA_FWMARK]); |
583 | if (nlrule->mark) |
584 | /* compatibility: if the mark value is non-zero all bits |
585 | * are compared unless a mask is explicitly specified. |
586 | */ |
587 | nlrule->mark_mask = 0xFFFFFFFF; |
588 | } |
589 | |
590 | if (tb[FRA_FWMASK]) |
591 | nlrule->mark_mask = nla_get_u32(nla: tb[FRA_FWMASK]); |
592 | |
593 | if (tb[FRA_TUN_ID]) |
594 | nlrule->tun_id = nla_get_be64(nla: tb[FRA_TUN_ID]); |
595 | |
596 | if (tb[FRA_L3MDEV] && |
597 | fib_nl2rule_l3mdev(nla: tb[FRA_L3MDEV], nlrule, extack) < 0) |
598 | goto errout_free; |
599 | |
600 | nlrule->action = frh->action; |
601 | nlrule->flags = frh->flags; |
602 | nlrule->table = frh_get_table(frh, nla: tb); |
603 | if (tb[FRA_SUPPRESS_PREFIXLEN]) |
604 | nlrule->suppress_prefixlen = nla_get_u32(nla: tb[FRA_SUPPRESS_PREFIXLEN]); |
605 | else |
606 | nlrule->suppress_prefixlen = -1; |
607 | |
608 | if (tb[FRA_SUPPRESS_IFGROUP]) |
609 | nlrule->suppress_ifgroup = nla_get_u32(nla: tb[FRA_SUPPRESS_IFGROUP]); |
610 | else |
611 | nlrule->suppress_ifgroup = -1; |
612 | |
613 | if (tb[FRA_GOTO]) { |
614 | if (nlrule->action != FR_ACT_GOTO) { |
615 | NL_SET_ERR_MSG(extack, "Unexpected goto" ); |
616 | goto errout_free; |
617 | } |
618 | |
619 | nlrule->target = nla_get_u32(nla: tb[FRA_GOTO]); |
620 | /* Backward jumps are prohibited to avoid endless loops */ |
621 | if (nlrule->target <= nlrule->pref) { |
622 | NL_SET_ERR_MSG(extack, "Backward goto not supported" ); |
623 | goto errout_free; |
624 | } |
625 | } else if (nlrule->action == FR_ACT_GOTO) { |
626 | NL_SET_ERR_MSG(extack, "Missing goto target for action goto" ); |
627 | goto errout_free; |
628 | } |
629 | |
630 | if (nlrule->l3mdev && nlrule->table) { |
631 | NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive" ); |
632 | goto errout_free; |
633 | } |
634 | |
635 | if (tb[FRA_UID_RANGE]) { |
636 | if (current_user_ns() != net->user_ns) { |
637 | err = -EPERM; |
638 | NL_SET_ERR_MSG(extack, "No permission to set uid" ); |
639 | goto errout_free; |
640 | } |
641 | |
642 | nlrule->uid_range = nla_get_kuid_range(tb); |
643 | |
644 | if (!uid_range_set(range: &nlrule->uid_range) || |
645 | !uid_lte(left: nlrule->uid_range.start, right: nlrule->uid_range.end)) { |
646 | NL_SET_ERR_MSG(extack, "Invalid uid range" ); |
647 | goto errout_free; |
648 | } |
649 | } else { |
650 | nlrule->uid_range = fib_kuid_range_unset; |
651 | } |
652 | |
653 | if (tb[FRA_IP_PROTO]) |
654 | nlrule->ip_proto = nla_get_u8(nla: tb[FRA_IP_PROTO]); |
655 | |
656 | if (tb[FRA_SPORT_RANGE]) { |
657 | err = nla_get_port_range(pattr: tb[FRA_SPORT_RANGE], |
658 | port_range: &nlrule->sport_range); |
659 | if (err) { |
660 | NL_SET_ERR_MSG(extack, "Invalid sport range" ); |
661 | goto errout_free; |
662 | } |
663 | } |
664 | |
665 | if (tb[FRA_DPORT_RANGE]) { |
666 | err = nla_get_port_range(pattr: tb[FRA_DPORT_RANGE], |
667 | port_range: &nlrule->dport_range); |
668 | if (err) { |
669 | NL_SET_ERR_MSG(extack, "Invalid dport range" ); |
670 | goto errout_free; |
671 | } |
672 | } |
673 | |
674 | *rule = nlrule; |
675 | |
676 | return 0; |
677 | |
678 | errout_free: |
679 | kfree(objp: nlrule); |
680 | errout: |
681 | return err; |
682 | } |
683 | |
684 | static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh, |
685 | struct nlattr **tb, struct fib_rule *rule) |
686 | { |
687 | struct fib_rule *r; |
688 | |
689 | list_for_each_entry(r, &ops->rules_list, list) { |
690 | if (r->action != rule->action) |
691 | continue; |
692 | |
693 | if (r->table != rule->table) |
694 | continue; |
695 | |
696 | if (r->pref != rule->pref) |
697 | continue; |
698 | |
699 | if (memcmp(p: r->iifname, q: rule->iifname, IFNAMSIZ)) |
700 | continue; |
701 | |
702 | if (memcmp(p: r->oifname, q: rule->oifname, IFNAMSIZ)) |
703 | continue; |
704 | |
705 | if (r->mark != rule->mark) |
706 | continue; |
707 | |
708 | if (r->suppress_ifgroup != rule->suppress_ifgroup) |
709 | continue; |
710 | |
711 | if (r->suppress_prefixlen != rule->suppress_prefixlen) |
712 | continue; |
713 | |
714 | if (r->mark_mask != rule->mark_mask) |
715 | continue; |
716 | |
717 | if (r->tun_id != rule->tun_id) |
718 | continue; |
719 | |
720 | if (r->fr_net != rule->fr_net) |
721 | continue; |
722 | |
723 | if (r->l3mdev != rule->l3mdev) |
724 | continue; |
725 | |
726 | if (!uid_eq(left: r->uid_range.start, right: rule->uid_range.start) || |
727 | !uid_eq(left: r->uid_range.end, right: rule->uid_range.end)) |
728 | continue; |
729 | |
730 | if (r->ip_proto != rule->ip_proto) |
731 | continue; |
732 | |
733 | if (r->proto != rule->proto) |
734 | continue; |
735 | |
736 | if (!fib_rule_port_range_compare(a: &r->sport_range, |
737 | b: &rule->sport_range)) |
738 | continue; |
739 | |
740 | if (!fib_rule_port_range_compare(a: &r->dport_range, |
741 | b: &rule->dport_range)) |
742 | continue; |
743 | |
744 | if (!ops->compare(r, frh, tb)) |
745 | continue; |
746 | return 1; |
747 | } |
748 | return 0; |
749 | } |
750 | |
751 | static const struct nla_policy fib_rule_policy[FRA_MAX + 1] = { |
752 | [FRA_UNSPEC] = { .strict_start_type = FRA_DPORT_RANGE + 1 }, |
753 | [FRA_IIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, |
754 | [FRA_OIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, |
755 | [FRA_PRIORITY] = { .type = NLA_U32 }, |
756 | [FRA_FWMARK] = { .type = NLA_U32 }, |
757 | [FRA_FLOW] = { .type = NLA_U32 }, |
758 | [FRA_TUN_ID] = { .type = NLA_U64 }, |
759 | [FRA_FWMASK] = { .type = NLA_U32 }, |
760 | [FRA_TABLE] = { .type = NLA_U32 }, |
761 | [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, |
762 | [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, |
763 | [FRA_GOTO] = { .type = NLA_U32 }, |
764 | [FRA_L3MDEV] = { .type = NLA_U8 }, |
765 | [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) }, |
766 | [FRA_PROTOCOL] = { .type = NLA_U8 }, |
767 | [FRA_IP_PROTO] = { .type = NLA_U8 }, |
768 | [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) }, |
769 | [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) } |
770 | }; |
771 | |
772 | int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh, |
773 | struct netlink_ext_ack *extack) |
774 | { |
775 | struct net *net = sock_net(sk: skb->sk); |
776 | struct fib_rule_hdr *frh = nlmsg_data(nlh); |
777 | struct fib_rules_ops *ops = NULL; |
778 | struct fib_rule *rule = NULL, *r, *last = NULL; |
779 | struct nlattr *tb[FRA_MAX + 1]; |
780 | int err = -EINVAL, unresolved = 0; |
781 | bool user_priority = false; |
782 | |
783 | if (nlh->nlmsg_len < nlmsg_msg_size(payload: sizeof(*frh))) { |
784 | NL_SET_ERR_MSG(extack, "Invalid msg length" ); |
785 | goto errout; |
786 | } |
787 | |
788 | ops = lookup_rules_ops(net, family: frh->family); |
789 | if (!ops) { |
790 | err = -EAFNOSUPPORT; |
791 | NL_SET_ERR_MSG(extack, "Rule family not supported" ); |
792 | goto errout; |
793 | } |
794 | |
795 | err = nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*frh), tb, FRA_MAX, |
796 | policy: fib_rule_policy, extack); |
797 | if (err < 0) { |
798 | NL_SET_ERR_MSG(extack, "Error parsing msg" ); |
799 | goto errout; |
800 | } |
801 | |
802 | err = fib_nl2rule(skb, nlh, extack, ops, tb, rule: &rule, user_priority: &user_priority); |
803 | if (err) |
804 | goto errout; |
805 | |
806 | if ((nlh->nlmsg_flags & NLM_F_EXCL) && |
807 | rule_exists(ops, frh, tb, rule)) { |
808 | err = -EEXIST; |
809 | goto errout_free; |
810 | } |
811 | |
812 | err = ops->configure(rule, skb, frh, tb, extack); |
813 | if (err < 0) |
814 | goto errout_free; |
815 | |
816 | err = call_fib_rule_notifiers(net, event_type: FIB_EVENT_RULE_ADD, rule, ops, |
817 | extack); |
818 | if (err < 0) |
819 | goto errout_free; |
820 | |
821 | list_for_each_entry(r, &ops->rules_list, list) { |
822 | if (r->pref == rule->target) { |
823 | RCU_INIT_POINTER(rule->ctarget, r); |
824 | break; |
825 | } |
826 | } |
827 | |
828 | if (rcu_dereference_protected(rule->ctarget, 1) == NULL) |
829 | unresolved = 1; |
830 | |
831 | list_for_each_entry(r, &ops->rules_list, list) { |
832 | if (r->pref > rule->pref) |
833 | break; |
834 | last = r; |
835 | } |
836 | |
837 | if (last) |
838 | list_add_rcu(new: &rule->list, head: &last->list); |
839 | else |
840 | list_add_rcu(new: &rule->list, head: &ops->rules_list); |
841 | |
842 | if (ops->unresolved_rules) { |
843 | /* |
844 | * There are unresolved goto rules in the list, check if |
845 | * any of them are pointing to this new rule. |
846 | */ |
847 | list_for_each_entry(r, &ops->rules_list, list) { |
848 | if (r->action == FR_ACT_GOTO && |
849 | r->target == rule->pref && |
850 | rtnl_dereference(r->ctarget) == NULL) { |
851 | rcu_assign_pointer(r->ctarget, rule); |
852 | if (--ops->unresolved_rules == 0) |
853 | break; |
854 | } |
855 | } |
856 | } |
857 | |
858 | if (rule->action == FR_ACT_GOTO) |
859 | ops->nr_goto_rules++; |
860 | |
861 | if (unresolved) |
862 | ops->unresolved_rules++; |
863 | |
864 | if (rule->tun_id) |
865 | ip_tunnel_need_metadata(); |
866 | |
867 | notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid); |
868 | flush_route_cache(ops); |
869 | rules_ops_put(ops); |
870 | return 0; |
871 | |
872 | errout_free: |
873 | kfree(objp: rule); |
874 | errout: |
875 | rules_ops_put(ops); |
876 | return err; |
877 | } |
878 | EXPORT_SYMBOL_GPL(fib_nl_newrule); |
879 | |
880 | int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh, |
881 | struct netlink_ext_ack *extack) |
882 | { |
883 | struct net *net = sock_net(sk: skb->sk); |
884 | struct fib_rule_hdr *frh = nlmsg_data(nlh); |
885 | struct fib_rules_ops *ops = NULL; |
886 | struct fib_rule *rule = NULL, *r, *nlrule = NULL; |
887 | struct nlattr *tb[FRA_MAX+1]; |
888 | int err = -EINVAL; |
889 | bool user_priority = false; |
890 | |
891 | if (nlh->nlmsg_len < nlmsg_msg_size(payload: sizeof(*frh))) { |
892 | NL_SET_ERR_MSG(extack, "Invalid msg length" ); |
893 | goto errout; |
894 | } |
895 | |
896 | ops = lookup_rules_ops(net, family: frh->family); |
897 | if (ops == NULL) { |
898 | err = -EAFNOSUPPORT; |
899 | NL_SET_ERR_MSG(extack, "Rule family not supported" ); |
900 | goto errout; |
901 | } |
902 | |
903 | err = nlmsg_parse_deprecated(nlh, hdrlen: sizeof(*frh), tb, FRA_MAX, |
904 | policy: fib_rule_policy, extack); |
905 | if (err < 0) { |
906 | NL_SET_ERR_MSG(extack, "Error parsing msg" ); |
907 | goto errout; |
908 | } |
909 | |
910 | err = fib_nl2rule(skb, nlh, extack, ops, tb, rule: &nlrule, user_priority: &user_priority); |
911 | if (err) |
912 | goto errout; |
913 | |
914 | rule = rule_find(ops, frh, tb, rule: nlrule, user_priority); |
915 | if (!rule) { |
916 | err = -ENOENT; |
917 | goto errout; |
918 | } |
919 | |
920 | if (rule->flags & FIB_RULE_PERMANENT) { |
921 | err = -EPERM; |
922 | goto errout; |
923 | } |
924 | |
925 | if (ops->delete) { |
926 | err = ops->delete(rule); |
927 | if (err) |
928 | goto errout; |
929 | } |
930 | |
931 | if (rule->tun_id) |
932 | ip_tunnel_unneed_metadata(); |
933 | |
934 | list_del_rcu(entry: &rule->list); |
935 | |
936 | if (rule->action == FR_ACT_GOTO) { |
937 | ops->nr_goto_rules--; |
938 | if (rtnl_dereference(rule->ctarget) == NULL) |
939 | ops->unresolved_rules--; |
940 | } |
941 | |
942 | /* |
943 | * Check if this rule is a target to any of them. If so, |
944 | * adjust to the next one with the same preference or |
945 | * disable them. As this operation is eventually very |
946 | * expensive, it is only performed if goto rules, except |
947 | * current if it is goto rule, have actually been added. |
948 | */ |
949 | if (ops->nr_goto_rules > 0) { |
950 | struct fib_rule *n; |
951 | |
952 | n = list_next_entry(rule, list); |
953 | if (&n->list == &ops->rules_list || n->pref != rule->pref) |
954 | n = NULL; |
955 | list_for_each_entry(r, &ops->rules_list, list) { |
956 | if (rtnl_dereference(r->ctarget) != rule) |
957 | continue; |
958 | rcu_assign_pointer(r->ctarget, n); |
959 | if (!n) |
960 | ops->unresolved_rules++; |
961 | } |
962 | } |
963 | |
964 | call_fib_rule_notifiers(net, event_type: FIB_EVENT_RULE_DEL, rule, ops, |
965 | NULL); |
966 | notify_rule_change(RTM_DELRULE, rule, ops, nlh, |
967 | NETLINK_CB(skb).portid); |
968 | fib_rule_put(rule); |
969 | flush_route_cache(ops); |
970 | rules_ops_put(ops); |
971 | kfree(objp: nlrule); |
972 | return 0; |
973 | |
974 | errout: |
975 | kfree(objp: nlrule); |
976 | rules_ops_put(ops); |
977 | return err; |
978 | } |
979 | EXPORT_SYMBOL_GPL(fib_nl_delrule); |
980 | |
981 | static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops, |
982 | struct fib_rule *rule) |
983 | { |
984 | size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr)) |
985 | + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */ |
986 | + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */ |
987 | + nla_total_size(payload: 4) /* FRA_PRIORITY */ |
988 | + nla_total_size(payload: 4) /* FRA_TABLE */ |
989 | + nla_total_size(payload: 4) /* FRA_SUPPRESS_PREFIXLEN */ |
990 | + nla_total_size(payload: 4) /* FRA_SUPPRESS_IFGROUP */ |
991 | + nla_total_size(payload: 4) /* FRA_FWMARK */ |
992 | + nla_total_size(payload: 4) /* FRA_FWMASK */ |
993 | + nla_total_size_64bit(payload: 8) /* FRA_TUN_ID */ |
994 | + nla_total_size(payload: sizeof(struct fib_kuid_range)) |
995 | + nla_total_size(payload: 1) /* FRA_PROTOCOL */ |
996 | + nla_total_size(payload: 1) /* FRA_IP_PROTO */ |
997 | + nla_total_size(payload: sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */ |
998 | + nla_total_size(payload: sizeof(struct fib_rule_port_range)); /* FRA_DPORT_RANGE */ |
999 | |
1000 | if (ops->nlmsg_payload) |
1001 | payload += ops->nlmsg_payload(rule); |
1002 | |
1003 | return payload; |
1004 | } |
1005 | |
1006 | static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule, |
1007 | u32 pid, u32 seq, int type, int flags, |
1008 | struct fib_rules_ops *ops) |
1009 | { |
1010 | struct nlmsghdr *nlh; |
1011 | struct fib_rule_hdr *frh; |
1012 | |
1013 | nlh = nlmsg_put(skb, portid: pid, seq, type, payload: sizeof(*frh), flags); |
1014 | if (nlh == NULL) |
1015 | return -EMSGSIZE; |
1016 | |
1017 | frh = nlmsg_data(nlh); |
1018 | frh->family = ops->family; |
1019 | frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT; |
1020 | if (nla_put_u32(skb, attrtype: FRA_TABLE, value: rule->table)) |
1021 | goto nla_put_failure; |
1022 | if (nla_put_u32(skb, attrtype: FRA_SUPPRESS_PREFIXLEN, value: rule->suppress_prefixlen)) |
1023 | goto nla_put_failure; |
1024 | frh->res1 = 0; |
1025 | frh->res2 = 0; |
1026 | frh->action = rule->action; |
1027 | frh->flags = rule->flags; |
1028 | |
1029 | if (nla_put_u8(skb, attrtype: FRA_PROTOCOL, value: rule->proto)) |
1030 | goto nla_put_failure; |
1031 | |
1032 | if (rule->action == FR_ACT_GOTO && |
1033 | rcu_access_pointer(rule->ctarget) == NULL) |
1034 | frh->flags |= FIB_RULE_UNRESOLVED; |
1035 | |
1036 | if (rule->iifname[0]) { |
1037 | if (nla_put_string(skb, attrtype: FRA_IIFNAME, str: rule->iifname)) |
1038 | goto nla_put_failure; |
1039 | if (rule->iifindex == -1) |
1040 | frh->flags |= FIB_RULE_IIF_DETACHED; |
1041 | } |
1042 | |
1043 | if (rule->oifname[0]) { |
1044 | if (nla_put_string(skb, attrtype: FRA_OIFNAME, str: rule->oifname)) |
1045 | goto nla_put_failure; |
1046 | if (rule->oifindex == -1) |
1047 | frh->flags |= FIB_RULE_OIF_DETACHED; |
1048 | } |
1049 | |
1050 | if ((rule->pref && |
1051 | nla_put_u32(skb, attrtype: FRA_PRIORITY, value: rule->pref)) || |
1052 | (rule->mark && |
1053 | nla_put_u32(skb, attrtype: FRA_FWMARK, value: rule->mark)) || |
1054 | ((rule->mark_mask || rule->mark) && |
1055 | nla_put_u32(skb, attrtype: FRA_FWMASK, value: rule->mark_mask)) || |
1056 | (rule->target && |
1057 | nla_put_u32(skb, attrtype: FRA_GOTO, value: rule->target)) || |
1058 | (rule->tun_id && |
1059 | nla_put_be64(skb, attrtype: FRA_TUN_ID, value: rule->tun_id, padattr: FRA_PAD)) || |
1060 | (rule->l3mdev && |
1061 | nla_put_u8(skb, attrtype: FRA_L3MDEV, value: rule->l3mdev)) || |
1062 | (uid_range_set(range: &rule->uid_range) && |
1063 | nla_put_uid_range(skb, range: &rule->uid_range)) || |
1064 | (fib_rule_port_range_set(range: &rule->sport_range) && |
1065 | nla_put_port_range(skb, attrtype: FRA_SPORT_RANGE, range: &rule->sport_range)) || |
1066 | (fib_rule_port_range_set(range: &rule->dport_range) && |
1067 | nla_put_port_range(skb, attrtype: FRA_DPORT_RANGE, range: &rule->dport_range)) || |
1068 | (rule->ip_proto && nla_put_u8(skb, attrtype: FRA_IP_PROTO, value: rule->ip_proto))) |
1069 | goto nla_put_failure; |
1070 | |
1071 | if (rule->suppress_ifgroup != -1) { |
1072 | if (nla_put_u32(skb, attrtype: FRA_SUPPRESS_IFGROUP, value: rule->suppress_ifgroup)) |
1073 | goto nla_put_failure; |
1074 | } |
1075 | |
1076 | if (ops->fill(rule, skb, frh) < 0) |
1077 | goto nla_put_failure; |
1078 | |
1079 | nlmsg_end(skb, nlh); |
1080 | return 0; |
1081 | |
1082 | nla_put_failure: |
1083 | nlmsg_cancel(skb, nlh); |
1084 | return -EMSGSIZE; |
1085 | } |
1086 | |
1087 | static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb, |
1088 | struct fib_rules_ops *ops) |
1089 | { |
1090 | int idx = 0; |
1091 | struct fib_rule *rule; |
1092 | int err = 0; |
1093 | |
1094 | rcu_read_lock(); |
1095 | list_for_each_entry_rcu(rule, &ops->rules_list, list) { |
1096 | if (idx < cb->args[1]) |
1097 | goto skip; |
1098 | |
1099 | err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid, |
1100 | seq: cb->nlh->nlmsg_seq, RTM_NEWRULE, |
1101 | NLM_F_MULTI, ops); |
1102 | if (err) |
1103 | break; |
1104 | skip: |
1105 | idx++; |
1106 | } |
1107 | rcu_read_unlock(); |
1108 | cb->args[1] = idx; |
1109 | rules_ops_put(ops); |
1110 | |
1111 | return err; |
1112 | } |
1113 | |
1114 | static int fib_valid_dumprule_req(const struct nlmsghdr *nlh, |
1115 | struct netlink_ext_ack *extack) |
1116 | { |
1117 | struct fib_rule_hdr *frh; |
1118 | |
1119 | if (nlh->nlmsg_len < nlmsg_msg_size(payload: sizeof(*frh))) { |
1120 | NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request" ); |
1121 | return -EINVAL; |
1122 | } |
1123 | |
1124 | frh = nlmsg_data(nlh); |
1125 | if (frh->dst_len || frh->src_len || frh->tos || frh->table || |
1126 | frh->res1 || frh->res2 || frh->action || frh->flags) { |
1127 | NL_SET_ERR_MSG(extack, |
1128 | "Invalid values in header for fib rule dump request" ); |
1129 | return -EINVAL; |
1130 | } |
1131 | |
1132 | if (nlmsg_attrlen(nlh, hdrlen: sizeof(*frh))) { |
1133 | NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request" ); |
1134 | return -EINVAL; |
1135 | } |
1136 | |
1137 | return 0; |
1138 | } |
1139 | |
1140 | static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb) |
1141 | { |
1142 | const struct nlmsghdr *nlh = cb->nlh; |
1143 | struct net *net = sock_net(sk: skb->sk); |
1144 | struct fib_rules_ops *ops; |
1145 | int idx = 0, family; |
1146 | |
1147 | if (cb->strict_check) { |
1148 | int err = fib_valid_dumprule_req(nlh, extack: cb->extack); |
1149 | |
1150 | if (err < 0) |
1151 | return err; |
1152 | } |
1153 | |
1154 | family = rtnl_msg_family(nlh); |
1155 | if (family != AF_UNSPEC) { |
1156 | /* Protocol specific dump request */ |
1157 | ops = lookup_rules_ops(net, family); |
1158 | if (ops == NULL) |
1159 | return -EAFNOSUPPORT; |
1160 | |
1161 | dump_rules(skb, cb, ops); |
1162 | |
1163 | return skb->len; |
1164 | } |
1165 | |
1166 | rcu_read_lock(); |
1167 | list_for_each_entry_rcu(ops, &net->rules_ops, list) { |
1168 | if (idx < cb->args[0] || !try_module_get(module: ops->owner)) |
1169 | goto skip; |
1170 | |
1171 | if (dump_rules(skb, cb, ops) < 0) |
1172 | break; |
1173 | |
1174 | cb->args[1] = 0; |
1175 | skip: |
1176 | idx++; |
1177 | } |
1178 | rcu_read_unlock(); |
1179 | cb->args[0] = idx; |
1180 | |
1181 | return skb->len; |
1182 | } |
1183 | |
1184 | static void notify_rule_change(int event, struct fib_rule *rule, |
1185 | struct fib_rules_ops *ops, struct nlmsghdr *nlh, |
1186 | u32 pid) |
1187 | { |
1188 | struct net *net; |
1189 | struct sk_buff *skb; |
1190 | int err = -ENOMEM; |
1191 | |
1192 | net = ops->fro_net; |
1193 | skb = nlmsg_new(payload: fib_rule_nlmsg_size(ops, rule), GFP_KERNEL); |
1194 | if (skb == NULL) |
1195 | goto errout; |
1196 | |
1197 | err = fib_nl_fill_rule(skb, rule, pid, seq: nlh->nlmsg_seq, type: event, flags: 0, ops); |
1198 | if (err < 0) { |
1199 | /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */ |
1200 | WARN_ON(err == -EMSGSIZE); |
1201 | kfree_skb(skb); |
1202 | goto errout; |
1203 | } |
1204 | |
1205 | rtnl_notify(skb, net, pid, group: ops->nlgroup, nlh, GFP_KERNEL); |
1206 | return; |
1207 | errout: |
1208 | if (err < 0) |
1209 | rtnl_set_sk_err(net, group: ops->nlgroup, error: err); |
1210 | } |
1211 | |
1212 | static void attach_rules(struct list_head *rules, struct net_device *dev) |
1213 | { |
1214 | struct fib_rule *rule; |
1215 | |
1216 | list_for_each_entry(rule, rules, list) { |
1217 | if (rule->iifindex == -1 && |
1218 | strcmp(dev->name, rule->iifname) == 0) |
1219 | rule->iifindex = dev->ifindex; |
1220 | if (rule->oifindex == -1 && |
1221 | strcmp(dev->name, rule->oifname) == 0) |
1222 | rule->oifindex = dev->ifindex; |
1223 | } |
1224 | } |
1225 | |
1226 | static void detach_rules(struct list_head *rules, struct net_device *dev) |
1227 | { |
1228 | struct fib_rule *rule; |
1229 | |
1230 | list_for_each_entry(rule, rules, list) { |
1231 | if (rule->iifindex == dev->ifindex) |
1232 | rule->iifindex = -1; |
1233 | if (rule->oifindex == dev->ifindex) |
1234 | rule->oifindex = -1; |
1235 | } |
1236 | } |
1237 | |
1238 | |
1239 | static int fib_rules_event(struct notifier_block *this, unsigned long event, |
1240 | void *ptr) |
1241 | { |
1242 | struct net_device *dev = netdev_notifier_info_to_dev(info: ptr); |
1243 | struct net *net = dev_net(dev); |
1244 | struct fib_rules_ops *ops; |
1245 | |
1246 | ASSERT_RTNL(); |
1247 | |
1248 | switch (event) { |
1249 | case NETDEV_REGISTER: |
1250 | list_for_each_entry(ops, &net->rules_ops, list) |
1251 | attach_rules(rules: &ops->rules_list, dev); |
1252 | break; |
1253 | |
1254 | case NETDEV_CHANGENAME: |
1255 | list_for_each_entry(ops, &net->rules_ops, list) { |
1256 | detach_rules(rules: &ops->rules_list, dev); |
1257 | attach_rules(rules: &ops->rules_list, dev); |
1258 | } |
1259 | break; |
1260 | |
1261 | case NETDEV_UNREGISTER: |
1262 | list_for_each_entry(ops, &net->rules_ops, list) |
1263 | detach_rules(rules: &ops->rules_list, dev); |
1264 | break; |
1265 | } |
1266 | |
1267 | return NOTIFY_DONE; |
1268 | } |
1269 | |
1270 | static struct notifier_block fib_rules_notifier = { |
1271 | .notifier_call = fib_rules_event, |
1272 | }; |
1273 | |
1274 | static int __net_init fib_rules_net_init(struct net *net) |
1275 | { |
1276 | INIT_LIST_HEAD(list: &net->rules_ops); |
1277 | spin_lock_init(&net->rules_mod_lock); |
1278 | return 0; |
1279 | } |
1280 | |
1281 | static void __net_exit fib_rules_net_exit(struct net *net) |
1282 | { |
1283 | WARN_ON_ONCE(!list_empty(&net->rules_ops)); |
1284 | } |
1285 | |
1286 | static struct pernet_operations fib_rules_net_ops = { |
1287 | .init = fib_rules_net_init, |
1288 | .exit = fib_rules_net_exit, |
1289 | }; |
1290 | |
1291 | static int __init fib_rules_init(void) |
1292 | { |
1293 | int err; |
1294 | rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, flags: 0); |
1295 | rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, flags: 0); |
1296 | rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, flags: 0); |
1297 | |
1298 | err = register_pernet_subsys(&fib_rules_net_ops); |
1299 | if (err < 0) |
1300 | goto fail; |
1301 | |
1302 | err = register_netdevice_notifier(nb: &fib_rules_notifier); |
1303 | if (err < 0) |
1304 | goto fail_unregister; |
1305 | |
1306 | return 0; |
1307 | |
1308 | fail_unregister: |
1309 | unregister_pernet_subsys(&fib_rules_net_ops); |
1310 | fail: |
1311 | rtnl_unregister(PF_UNSPEC, RTM_NEWRULE); |
1312 | rtnl_unregister(PF_UNSPEC, RTM_DELRULE); |
1313 | rtnl_unregister(PF_UNSPEC, RTM_GETRULE); |
1314 | return err; |
1315 | } |
1316 | |
1317 | subsys_initcall(fib_rules_init); |
1318 | |