1 // SPDX-License-Identifier: GPL-2.0-only
3 * net/core/fib_rules.c Generic Routing Rules
5 * Authors: Thomas Graf <tgraf@suug.ch>
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>
15 #include <net/fib_rules.h>
16 #include <net/ip_tunnels.h>
18 static const struct fib_kuid_range fib_kuid_range_unset = {
23 bool fib_rule_matchall(const struct fib_rule *rule)
25 if (rule->iifindex || rule->oifindex || rule->mark || rule->tun_id ||
28 if (rule->suppress_ifgroup != -1 || rule->suppress_prefixlen != -1)
30 if (!uid_eq(rule->uid_range.start, fib_kuid_range_unset.start) ||
31 !uid_eq(rule->uid_range.end, fib_kuid_range_unset.end))
33 if (fib_rule_port_range_set(&rule->sport_range))
35 if (fib_rule_port_range_set(&rule->dport_range))
39 EXPORT_SYMBOL_GPL(fib_rule_matchall);
41 int fib_default_rule_add(struct fib_rules_ops *ops,
42 u32 pref, u32 table, u32 flags)
46 r = kzalloc(ops->rule_size, GFP_KERNEL);
50 refcount_set(&r->refcnt, 1);
51 r->action = FR_ACT_TO_TBL;
55 r->proto = RTPROT_KERNEL;
56 r->fr_net = ops->fro_net;
57 r->uid_range = fib_kuid_range_unset;
59 r->suppress_prefixlen = -1;
60 r->suppress_ifgroup = -1;
62 /* The lock is not required here, the list in unreacheable
63 * at the moment this function is called */
64 list_add_tail(&r->list, &ops->rules_list);
67 EXPORT_SYMBOL(fib_default_rule_add);
69 static u32 fib_default_rule_pref(struct fib_rules_ops *ops)
71 struct list_head *pos;
72 struct fib_rule *rule;
74 if (!list_empty(&ops->rules_list)) {
75 pos = ops->rules_list.next;
76 if (pos->next != &ops->rules_list) {
77 rule = list_entry(pos->next, struct fib_rule, list);
79 return rule->pref - 1;
86 static void notify_rule_change(int event, struct fib_rule *rule,
87 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
90 static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family)
92 struct fib_rules_ops *ops;
95 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
96 if (ops->family == family) {
97 if (!try_module_get(ops->owner))
108 static void rules_ops_put(struct fib_rules_ops *ops)
111 module_put(ops->owner);
114 static void flush_route_cache(struct fib_rules_ops *ops)
116 if (ops->flush_cache)
117 ops->flush_cache(ops);
120 static int __fib_rules_register(struct fib_rules_ops *ops)
123 struct fib_rules_ops *o;
128 if (ops->rule_size < sizeof(struct fib_rule))
131 if (ops->match == NULL || ops->configure == NULL ||
132 ops->compare == NULL || ops->fill == NULL ||
136 spin_lock(&net->rules_mod_lock);
137 list_for_each_entry(o, &net->rules_ops, list)
138 if (ops->family == o->family)
141 list_add_tail_rcu(&ops->list, &net->rules_ops);
144 spin_unlock(&net->rules_mod_lock);
149 struct fib_rules_ops *
150 fib_rules_register(const struct fib_rules_ops *tmpl, struct net *net)
152 struct fib_rules_ops *ops;
155 ops = kmemdup(tmpl, sizeof(*ops), GFP_KERNEL);
157 return ERR_PTR(-ENOMEM);
159 INIT_LIST_HEAD(&ops->rules_list);
162 err = __fib_rules_register(ops);
170 EXPORT_SYMBOL_GPL(fib_rules_register);
172 static void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
174 struct fib_rule *rule, *tmp;
176 list_for_each_entry_safe(rule, tmp, &ops->rules_list, list) {
177 list_del_rcu(&rule->list);
184 void fib_rules_unregister(struct fib_rules_ops *ops)
186 struct net *net = ops->fro_net;
188 spin_lock(&net->rules_mod_lock);
189 list_del_rcu(&ops->list);
190 spin_unlock(&net->rules_mod_lock);
192 fib_rules_cleanup_ops(ops);
195 EXPORT_SYMBOL_GPL(fib_rules_unregister);
197 static int uid_range_set(struct fib_kuid_range *range)
199 return uid_valid(range->start) && uid_valid(range->end);
202 static struct fib_kuid_range nla_get_kuid_range(struct nlattr **tb)
204 struct fib_rule_uid_range *in;
205 struct fib_kuid_range out;
207 in = (struct fib_rule_uid_range *)nla_data(tb[FRA_UID_RANGE]);
209 out.start = make_kuid(current_user_ns(), in->start);
210 out.end = make_kuid(current_user_ns(), in->end);
215 static int nla_put_uid_range(struct sk_buff *skb, struct fib_kuid_range *range)
217 struct fib_rule_uid_range out = {
218 from_kuid_munged(current_user_ns(), range->start),
219 from_kuid_munged(current_user_ns(), range->end)
222 return nla_put(skb, FRA_UID_RANGE, sizeof(out), &out);
225 static int nla_get_port_range(struct nlattr *pattr,
226 struct fib_rule_port_range *port_range)
228 const struct fib_rule_port_range *pr = nla_data(pattr);
230 if (!fib_rule_port_range_valid(pr))
233 port_range->start = pr->start;
234 port_range->end = pr->end;
239 static int nla_put_port_range(struct sk_buff *skb, int attrtype,
240 struct fib_rule_port_range *range)
242 return nla_put(skb, attrtype, sizeof(*range), range);
245 static int fib_rule_match(struct fib_rule *rule, struct fib_rules_ops *ops,
246 struct flowi *fl, int flags,
247 struct fib_lookup_arg *arg)
251 if (rule->iifindex && (rule->iifindex != fl->flowi_iif))
254 if (rule->oifindex && (rule->oifindex != fl->flowi_oif))
257 if ((rule->mark ^ fl->flowi_mark) & rule->mark_mask)
260 if (rule->tun_id && (rule->tun_id != fl->flowi_tun_key.tun_id))
263 if (rule->l3mdev && !l3mdev_fib_rule_match(rule->fr_net, fl, arg))
266 if (uid_lt(fl->flowi_uid, rule->uid_range.start) ||
267 uid_gt(fl->flowi_uid, rule->uid_range.end))
270 ret = ops->match(rule, fl, flags);
272 return (rule->flags & FIB_RULE_INVERT) ? !ret : ret;
275 int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
276 int flags, struct fib_lookup_arg *arg)
278 struct fib_rule *rule;
283 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
285 if (!fib_rule_match(rule, ops, fl, flags, arg))
288 if (rule->action == FR_ACT_GOTO) {
289 struct fib_rule *target;
291 target = rcu_dereference(rule->ctarget);
292 if (target == NULL) {
298 } else if (rule->action == FR_ACT_NOP)
301 err = ops->action(rule, fl, flags, arg);
303 if (!err && ops->suppress && ops->suppress(rule, flags, arg))
306 if (err != -EAGAIN) {
307 if ((arg->flags & FIB_LOOKUP_NOREF) ||
308 likely(refcount_inc_not_zero(&rule->refcnt))) {
322 EXPORT_SYMBOL_GPL(fib_rules_lookup);
324 static int call_fib_rule_notifier(struct notifier_block *nb, struct net *net,
325 enum fib_event_type event_type,
326 struct fib_rule *rule, int family)
328 struct fib_rule_notifier_info info = {
329 .info.family = family,
333 return call_fib_notifier(nb, net, event_type, &info.info);
336 static int call_fib_rule_notifiers(struct net *net,
337 enum fib_event_type event_type,
338 struct fib_rule *rule,
339 struct fib_rules_ops *ops,
340 struct netlink_ext_ack *extack)
342 struct fib_rule_notifier_info info = {
343 .info.family = ops->family,
344 .info.extack = extack,
348 ops->fib_rules_seq++;
349 return call_fib_notifiers(net, event_type, &info.info);
352 /* Called with rcu_read_lock() */
353 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family)
355 struct fib_rules_ops *ops;
356 struct fib_rule *rule;
358 ops = lookup_rules_ops(net, family);
360 return -EAFNOSUPPORT;
361 list_for_each_entry_rcu(rule, &ops->rules_list, list)
362 call_fib_rule_notifier(nb, net, FIB_EVENT_RULE_ADD, rule,
368 EXPORT_SYMBOL_GPL(fib_rules_dump);
370 unsigned int fib_rules_seq_read(struct net *net, int family)
372 unsigned int fib_rules_seq;
373 struct fib_rules_ops *ops;
377 ops = lookup_rules_ops(net, family);
380 fib_rules_seq = ops->fib_rules_seq;
383 return fib_rules_seq;
385 EXPORT_SYMBOL_GPL(fib_rules_seq_read);
387 static struct fib_rule *rule_find(struct fib_rules_ops *ops,
388 struct fib_rule_hdr *frh,
390 struct fib_rule *rule,
395 list_for_each_entry(r, &ops->rules_list, list) {
396 if (rule->action && r->action != rule->action)
399 if (rule->table && r->table != rule->table)
402 if (user_priority && r->pref != rule->pref)
405 if (rule->iifname[0] &&
406 memcmp(r->iifname, rule->iifname, IFNAMSIZ))
409 if (rule->oifname[0] &&
410 memcmp(r->oifname, rule->oifname, IFNAMSIZ))
413 if (rule->mark && r->mark != rule->mark)
416 if (rule->suppress_ifgroup != -1 &&
417 r->suppress_ifgroup != rule->suppress_ifgroup)
420 if (rule->suppress_prefixlen != -1 &&
421 r->suppress_prefixlen != rule->suppress_prefixlen)
424 if (rule->mark_mask && r->mark_mask != rule->mark_mask)
427 if (rule->tun_id && r->tun_id != rule->tun_id)
430 if (r->fr_net != rule->fr_net)
433 if (rule->l3mdev && r->l3mdev != rule->l3mdev)
436 if (uid_range_set(&rule->uid_range) &&
437 (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
438 !uid_eq(r->uid_range.end, rule->uid_range.end)))
441 if (rule->ip_proto && r->ip_proto != rule->ip_proto)
444 if (rule->proto && r->proto != rule->proto)
447 if (fib_rule_port_range_set(&rule->sport_range) &&
448 !fib_rule_port_range_compare(&r->sport_range,
452 if (fib_rule_port_range_set(&rule->dport_range) &&
453 !fib_rule_port_range_compare(&r->dport_range,
457 if (!ops->compare(r, frh, tb))
465 #ifdef CONFIG_NET_L3_MASTER_DEV
466 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
467 struct netlink_ext_ack *extack)
469 nlrule->l3mdev = nla_get_u8(nla);
470 if (nlrule->l3mdev != 1) {
471 NL_SET_ERR_MSG(extack, "Invalid l3mdev attribute");
478 static int fib_nl2rule_l3mdev(struct nlattr *nla, struct fib_rule *nlrule,
479 struct netlink_ext_ack *extack)
481 NL_SET_ERR_MSG(extack, "l3mdev support is not enabled in kernel");
486 static int fib_nl2rule(struct sk_buff *skb, struct nlmsghdr *nlh,
487 struct netlink_ext_ack *extack,
488 struct fib_rules_ops *ops,
490 struct fib_rule **rule,
493 struct net *net = sock_net(skb->sk);
494 struct fib_rule_hdr *frh = nlmsg_data(nlh);
495 struct fib_rule *nlrule = NULL;
500 frh->src_len > (ops->addr_size * 8) ||
501 nla_len(tb[FRA_SRC]) != ops->addr_size) {
502 NL_SET_ERR_MSG(extack, "Invalid source address");
508 frh->dst_len > (ops->addr_size * 8) ||
509 nla_len(tb[FRA_DST]) != ops->addr_size) {
510 NL_SET_ERR_MSG(extack, "Invalid dst address");
514 nlrule = kzalloc(ops->rule_size, GFP_KERNEL);
519 refcount_set(&nlrule->refcnt, 1);
520 nlrule->fr_net = net;
522 if (tb[FRA_PRIORITY]) {
523 nlrule->pref = nla_get_u32(tb[FRA_PRIORITY]);
524 *user_priority = true;
526 nlrule->pref = fib_default_rule_pref(ops);
529 nlrule->proto = tb[FRA_PROTOCOL] ?
530 nla_get_u8(tb[FRA_PROTOCOL]) : RTPROT_UNSPEC;
532 if (tb[FRA_IIFNAME]) {
533 struct net_device *dev;
535 nlrule->iifindex = -1;
536 nla_strlcpy(nlrule->iifname, tb[FRA_IIFNAME], IFNAMSIZ);
537 dev = __dev_get_by_name(net, nlrule->iifname);
539 nlrule->iifindex = dev->ifindex;
542 if (tb[FRA_OIFNAME]) {
543 struct net_device *dev;
545 nlrule->oifindex = -1;
546 nla_strlcpy(nlrule->oifname, tb[FRA_OIFNAME], IFNAMSIZ);
547 dev = __dev_get_by_name(net, nlrule->oifname);
549 nlrule->oifindex = dev->ifindex;
552 if (tb[FRA_FWMARK]) {
553 nlrule->mark = nla_get_u32(tb[FRA_FWMARK]);
555 /* compatibility: if the mark value is non-zero all bits
556 * are compared unless a mask is explicitly specified.
558 nlrule->mark_mask = 0xFFFFFFFF;
562 nlrule->mark_mask = nla_get_u32(tb[FRA_FWMASK]);
565 nlrule->tun_id = nla_get_be64(tb[FRA_TUN_ID]);
568 if (tb[FRA_L3MDEV] &&
569 fib_nl2rule_l3mdev(tb[FRA_L3MDEV], nlrule, extack) < 0)
572 nlrule->action = frh->action;
573 nlrule->flags = frh->flags;
574 nlrule->table = frh_get_table(frh, tb);
575 if (tb[FRA_SUPPRESS_PREFIXLEN])
576 nlrule->suppress_prefixlen = nla_get_u32(tb[FRA_SUPPRESS_PREFIXLEN]);
578 nlrule->suppress_prefixlen = -1;
580 if (tb[FRA_SUPPRESS_IFGROUP])
581 nlrule->suppress_ifgroup = nla_get_u32(tb[FRA_SUPPRESS_IFGROUP]);
583 nlrule->suppress_ifgroup = -1;
586 if (nlrule->action != FR_ACT_GOTO) {
587 NL_SET_ERR_MSG(extack, "Unexpected goto");
591 nlrule->target = nla_get_u32(tb[FRA_GOTO]);
592 /* Backward jumps are prohibited to avoid endless loops */
593 if (nlrule->target <= nlrule->pref) {
594 NL_SET_ERR_MSG(extack, "Backward goto not supported");
597 } else if (nlrule->action == FR_ACT_GOTO) {
598 NL_SET_ERR_MSG(extack, "Missing goto target for action goto");
602 if (nlrule->l3mdev && nlrule->table) {
603 NL_SET_ERR_MSG(extack, "l3mdev and table are mutually exclusive");
607 if (tb[FRA_UID_RANGE]) {
608 if (current_user_ns() != net->user_ns) {
610 NL_SET_ERR_MSG(extack, "No permission to set uid");
614 nlrule->uid_range = nla_get_kuid_range(tb);
616 if (!uid_range_set(&nlrule->uid_range) ||
617 !uid_lte(nlrule->uid_range.start, nlrule->uid_range.end)) {
618 NL_SET_ERR_MSG(extack, "Invalid uid range");
622 nlrule->uid_range = fib_kuid_range_unset;
625 if (tb[FRA_IP_PROTO])
626 nlrule->ip_proto = nla_get_u8(tb[FRA_IP_PROTO]);
628 if (tb[FRA_SPORT_RANGE]) {
629 err = nla_get_port_range(tb[FRA_SPORT_RANGE],
630 &nlrule->sport_range);
632 NL_SET_ERR_MSG(extack, "Invalid sport range");
637 if (tb[FRA_DPORT_RANGE]) {
638 err = nla_get_port_range(tb[FRA_DPORT_RANGE],
639 &nlrule->dport_range);
641 NL_SET_ERR_MSG(extack, "Invalid dport range");
656 static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh,
657 struct nlattr **tb, struct fib_rule *rule)
661 list_for_each_entry(r, &ops->rules_list, list) {
662 if (r->action != rule->action)
665 if (r->table != rule->table)
668 if (r->pref != rule->pref)
671 if (memcmp(r->iifname, rule->iifname, IFNAMSIZ))
674 if (memcmp(r->oifname, rule->oifname, IFNAMSIZ))
677 if (r->mark != rule->mark)
680 if (r->suppress_ifgroup != rule->suppress_ifgroup)
683 if (r->suppress_prefixlen != rule->suppress_prefixlen)
686 if (r->mark_mask != rule->mark_mask)
689 if (r->tun_id != rule->tun_id)
692 if (r->fr_net != rule->fr_net)
695 if (r->l3mdev != rule->l3mdev)
698 if (!uid_eq(r->uid_range.start, rule->uid_range.start) ||
699 !uid_eq(r->uid_range.end, rule->uid_range.end))
702 if (r->ip_proto != rule->ip_proto)
705 if (r->proto != rule->proto)
708 if (!fib_rule_port_range_compare(&r->sport_range,
712 if (!fib_rule_port_range_compare(&r->dport_range,
716 if (!ops->compare(r, frh, tb))
723 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
724 struct netlink_ext_ack *extack)
726 struct net *net = sock_net(skb->sk);
727 struct fib_rule_hdr *frh = nlmsg_data(nlh);
728 struct fib_rules_ops *ops = NULL;
729 struct fib_rule *rule = NULL, *r, *last = NULL;
730 struct nlattr *tb[FRA_MAX + 1];
731 int err = -EINVAL, unresolved = 0;
732 bool user_priority = false;
734 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
735 NL_SET_ERR_MSG(extack, "Invalid msg length");
739 ops = lookup_rules_ops(net, frh->family);
742 NL_SET_ERR_MSG(extack, "Rule family not supported");
746 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
747 ops->policy, extack);
749 NL_SET_ERR_MSG(extack, "Error parsing msg");
753 err = fib_nl2rule(skb, nlh, extack, ops, tb, &rule, &user_priority);
757 if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
758 rule_exists(ops, frh, tb, rule)) {
763 err = ops->configure(rule, skb, frh, tb, extack);
767 err = call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule, ops,
772 list_for_each_entry(r, &ops->rules_list, list) {
773 if (r->pref == rule->target) {
774 RCU_INIT_POINTER(rule->ctarget, r);
779 if (rcu_dereference_protected(rule->ctarget, 1) == NULL)
782 list_for_each_entry(r, &ops->rules_list, list) {
783 if (r->pref > rule->pref)
789 list_add_rcu(&rule->list, &last->list);
791 list_add_rcu(&rule->list, &ops->rules_list);
793 if (ops->unresolved_rules) {
795 * There are unresolved goto rules in the list, check if
796 * any of them are pointing to this new rule.
798 list_for_each_entry(r, &ops->rules_list, list) {
799 if (r->action == FR_ACT_GOTO &&
800 r->target == rule->pref &&
801 rtnl_dereference(r->ctarget) == NULL) {
802 rcu_assign_pointer(r->ctarget, rule);
803 if (--ops->unresolved_rules == 0)
809 if (rule->action == FR_ACT_GOTO)
810 ops->nr_goto_rules++;
813 ops->unresolved_rules++;
816 ip_tunnel_need_metadata();
818 notify_rule_change(RTM_NEWRULE, rule, ops, nlh, NETLINK_CB(skb).portid);
819 flush_route_cache(ops);
829 EXPORT_SYMBOL_GPL(fib_nl_newrule);
831 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
832 struct netlink_ext_ack *extack)
834 struct net *net = sock_net(skb->sk);
835 struct fib_rule_hdr *frh = nlmsg_data(nlh);
836 struct fib_rules_ops *ops = NULL;
837 struct fib_rule *rule = NULL, *r, *nlrule = NULL;
838 struct nlattr *tb[FRA_MAX+1];
840 bool user_priority = false;
842 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
843 NL_SET_ERR_MSG(extack, "Invalid msg length");
847 ops = lookup_rules_ops(net, frh->family);
850 NL_SET_ERR_MSG(extack, "Rule family not supported");
854 err = nlmsg_parse_deprecated(nlh, sizeof(*frh), tb, FRA_MAX,
855 ops->policy, extack);
857 NL_SET_ERR_MSG(extack, "Error parsing msg");
861 err = fib_nl2rule(skb, nlh, extack, ops, tb, &nlrule, &user_priority);
865 rule = rule_find(ops, frh, tb, nlrule, user_priority);
871 if (rule->flags & FIB_RULE_PERMANENT) {
877 err = ops->delete(rule);
883 ip_tunnel_unneed_metadata();
885 list_del_rcu(&rule->list);
887 if (rule->action == FR_ACT_GOTO) {
888 ops->nr_goto_rules--;
889 if (rtnl_dereference(rule->ctarget) == NULL)
890 ops->unresolved_rules--;
894 * Check if this rule is a target to any of them. If so,
895 * adjust to the next one with the same preference or
896 * disable them. As this operation is eventually very
897 * expensive, it is only performed if goto rules, except
898 * current if it is goto rule, have actually been added.
900 if (ops->nr_goto_rules > 0) {
903 n = list_next_entry(rule, list);
904 if (&n->list == &ops->rules_list || n->pref != rule->pref)
906 list_for_each_entry(r, &ops->rules_list, list) {
907 if (rtnl_dereference(r->ctarget) != rule)
909 rcu_assign_pointer(r->ctarget, n);
911 ops->unresolved_rules++;
915 call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule, ops,
917 notify_rule_change(RTM_DELRULE, rule, ops, nlh,
918 NETLINK_CB(skb).portid);
920 flush_route_cache(ops);
930 EXPORT_SYMBOL_GPL(fib_nl_delrule);
932 static inline size_t fib_rule_nlmsg_size(struct fib_rules_ops *ops,
933 struct fib_rule *rule)
935 size_t payload = NLMSG_ALIGN(sizeof(struct fib_rule_hdr))
936 + nla_total_size(IFNAMSIZ) /* FRA_IIFNAME */
937 + nla_total_size(IFNAMSIZ) /* FRA_OIFNAME */
938 + nla_total_size(4) /* FRA_PRIORITY */
939 + nla_total_size(4) /* FRA_TABLE */
940 + nla_total_size(4) /* FRA_SUPPRESS_PREFIXLEN */
941 + nla_total_size(4) /* FRA_SUPPRESS_IFGROUP */
942 + nla_total_size(4) /* FRA_FWMARK */
943 + nla_total_size(4) /* FRA_FWMASK */
944 + nla_total_size_64bit(8) /* FRA_TUN_ID */
945 + nla_total_size(sizeof(struct fib_kuid_range))
946 + nla_total_size(1) /* FRA_PROTOCOL */
947 + nla_total_size(1) /* FRA_IP_PROTO */
948 + nla_total_size(sizeof(struct fib_rule_port_range)) /* FRA_SPORT_RANGE */
949 + nla_total_size(sizeof(struct fib_rule_port_range)); /* FRA_DPORT_RANGE */
951 if (ops->nlmsg_payload)
952 payload += ops->nlmsg_payload(rule);
957 static int fib_nl_fill_rule(struct sk_buff *skb, struct fib_rule *rule,
958 u32 pid, u32 seq, int type, int flags,
959 struct fib_rules_ops *ops)
961 struct nlmsghdr *nlh;
962 struct fib_rule_hdr *frh;
964 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*frh), flags);
968 frh = nlmsg_data(nlh);
969 frh->family = ops->family;
970 frh->table = rule->table < 256 ? rule->table : RT_TABLE_COMPAT;
971 if (nla_put_u32(skb, FRA_TABLE, rule->table))
972 goto nla_put_failure;
973 if (nla_put_u32(skb, FRA_SUPPRESS_PREFIXLEN, rule->suppress_prefixlen))
974 goto nla_put_failure;
977 frh->action = rule->action;
978 frh->flags = rule->flags;
980 if (nla_put_u8(skb, FRA_PROTOCOL, rule->proto))
981 goto nla_put_failure;
983 if (rule->action == FR_ACT_GOTO &&
984 rcu_access_pointer(rule->ctarget) == NULL)
985 frh->flags |= FIB_RULE_UNRESOLVED;
987 if (rule->iifname[0]) {
988 if (nla_put_string(skb, FRA_IIFNAME, rule->iifname))
989 goto nla_put_failure;
990 if (rule->iifindex == -1)
991 frh->flags |= FIB_RULE_IIF_DETACHED;
994 if (rule->oifname[0]) {
995 if (nla_put_string(skb, FRA_OIFNAME, rule->oifname))
996 goto nla_put_failure;
997 if (rule->oifindex == -1)
998 frh->flags |= FIB_RULE_OIF_DETACHED;
1002 nla_put_u32(skb, FRA_PRIORITY, rule->pref)) ||
1004 nla_put_u32(skb, FRA_FWMARK, rule->mark)) ||
1005 ((rule->mark_mask || rule->mark) &&
1006 nla_put_u32(skb, FRA_FWMASK, rule->mark_mask)) ||
1008 nla_put_u32(skb, FRA_GOTO, rule->target)) ||
1010 nla_put_be64(skb, FRA_TUN_ID, rule->tun_id, FRA_PAD)) ||
1012 nla_put_u8(skb, FRA_L3MDEV, rule->l3mdev)) ||
1013 (uid_range_set(&rule->uid_range) &&
1014 nla_put_uid_range(skb, &rule->uid_range)) ||
1015 (fib_rule_port_range_set(&rule->sport_range) &&
1016 nla_put_port_range(skb, FRA_SPORT_RANGE, &rule->sport_range)) ||
1017 (fib_rule_port_range_set(&rule->dport_range) &&
1018 nla_put_port_range(skb, FRA_DPORT_RANGE, &rule->dport_range)) ||
1019 (rule->ip_proto && nla_put_u8(skb, FRA_IP_PROTO, rule->ip_proto)))
1020 goto nla_put_failure;
1022 if (rule->suppress_ifgroup != -1) {
1023 if (nla_put_u32(skb, FRA_SUPPRESS_IFGROUP, rule->suppress_ifgroup))
1024 goto nla_put_failure;
1027 if (ops->fill(rule, skb, frh) < 0)
1028 goto nla_put_failure;
1030 nlmsg_end(skb, nlh);
1034 nlmsg_cancel(skb, nlh);
1038 static int dump_rules(struct sk_buff *skb, struct netlink_callback *cb,
1039 struct fib_rules_ops *ops)
1042 struct fib_rule *rule;
1046 list_for_each_entry_rcu(rule, &ops->rules_list, list) {
1047 if (idx < cb->args[1])
1050 err = fib_nl_fill_rule(skb, rule, NETLINK_CB(cb->skb).portid,
1051 cb->nlh->nlmsg_seq, RTM_NEWRULE,
1065 static int fib_valid_dumprule_req(const struct nlmsghdr *nlh,
1066 struct netlink_ext_ack *extack)
1068 struct fib_rule_hdr *frh;
1070 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*frh))) {
1071 NL_SET_ERR_MSG(extack, "Invalid header for fib rule dump request");
1075 frh = nlmsg_data(nlh);
1076 if (frh->dst_len || frh->src_len || frh->tos || frh->table ||
1077 frh->res1 || frh->res2 || frh->action || frh->flags) {
1078 NL_SET_ERR_MSG(extack,
1079 "Invalid values in header for fib rule dump request");
1083 if (nlmsg_attrlen(nlh, sizeof(*frh))) {
1084 NL_SET_ERR_MSG(extack, "Invalid data after header in fib rule dump request");
1091 static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
1093 const struct nlmsghdr *nlh = cb->nlh;
1094 struct net *net = sock_net(skb->sk);
1095 struct fib_rules_ops *ops;
1096 int idx = 0, family;
1098 if (cb->strict_check) {
1099 int err = fib_valid_dumprule_req(nlh, cb->extack);
1105 family = rtnl_msg_family(nlh);
1106 if (family != AF_UNSPEC) {
1107 /* Protocol specific dump request */
1108 ops = lookup_rules_ops(net, family);
1110 return -EAFNOSUPPORT;
1112 dump_rules(skb, cb, ops);
1118 list_for_each_entry_rcu(ops, &net->rules_ops, list) {
1119 if (idx < cb->args[0] || !try_module_get(ops->owner))
1122 if (dump_rules(skb, cb, ops) < 0)
1135 static void notify_rule_change(int event, struct fib_rule *rule,
1136 struct fib_rules_ops *ops, struct nlmsghdr *nlh,
1140 struct sk_buff *skb;
1144 skb = nlmsg_new(fib_rule_nlmsg_size(ops, rule), GFP_KERNEL);
1148 err = fib_nl_fill_rule(skb, rule, pid, nlh->nlmsg_seq, event, 0, ops);
1150 /* -EMSGSIZE implies BUG in fib_rule_nlmsg_size() */
1151 WARN_ON(err == -EMSGSIZE);
1156 rtnl_notify(skb, net, pid, ops->nlgroup, nlh, GFP_KERNEL);
1160 rtnl_set_sk_err(net, ops->nlgroup, err);
1163 static void attach_rules(struct list_head *rules, struct net_device *dev)
1165 struct fib_rule *rule;
1167 list_for_each_entry(rule, rules, list) {
1168 if (rule->iifindex == -1 &&
1169 strcmp(dev->name, rule->iifname) == 0)
1170 rule->iifindex = dev->ifindex;
1171 if (rule->oifindex == -1 &&
1172 strcmp(dev->name, rule->oifname) == 0)
1173 rule->oifindex = dev->ifindex;
1177 static void detach_rules(struct list_head *rules, struct net_device *dev)
1179 struct fib_rule *rule;
1181 list_for_each_entry(rule, rules, list) {
1182 if (rule->iifindex == dev->ifindex)
1183 rule->iifindex = -1;
1184 if (rule->oifindex == dev->ifindex)
1185 rule->oifindex = -1;
1190 static int fib_rules_event(struct notifier_block *this, unsigned long event,
1193 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1194 struct net *net = dev_net(dev);
1195 struct fib_rules_ops *ops;
1200 case NETDEV_REGISTER:
1201 list_for_each_entry(ops, &net->rules_ops, list)
1202 attach_rules(&ops->rules_list, dev);
1205 case NETDEV_CHANGENAME:
1206 list_for_each_entry(ops, &net->rules_ops, list) {
1207 detach_rules(&ops->rules_list, dev);
1208 attach_rules(&ops->rules_list, dev);
1212 case NETDEV_UNREGISTER:
1213 list_for_each_entry(ops, &net->rules_ops, list)
1214 detach_rules(&ops->rules_list, dev);
1221 static struct notifier_block fib_rules_notifier = {
1222 .notifier_call = fib_rules_event,
1225 static int __net_init fib_rules_net_init(struct net *net)
1227 INIT_LIST_HEAD(&net->rules_ops);
1228 spin_lock_init(&net->rules_mod_lock);
1232 static void __net_exit fib_rules_net_exit(struct net *net)
1234 WARN_ON_ONCE(!list_empty(&net->rules_ops));
1237 static struct pernet_operations fib_rules_net_ops = {
1238 .init = fib_rules_net_init,
1239 .exit = fib_rules_net_exit,
1242 static int __init fib_rules_init(void)
1245 rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, 0);
1246 rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, 0);
1247 rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, 0);
1249 err = register_pernet_subsys(&fib_rules_net_ops);
1253 err = register_netdevice_notifier(&fib_rules_notifier);
1255 goto fail_unregister;
1260 unregister_pernet_subsys(&fib_rules_net_ops);
1262 rtnl_unregister(PF_UNSPEC, RTM_NEWRULE);
1263 rtnl_unregister(PF_UNSPEC, RTM_DELRULE);
1264 rtnl_unregister(PF_UNSPEC, RTM_GETRULE);
1268 subsys_initcall(fib_rules_init);