2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * IPv4 Forwarding Information Base: FIB frontend.
8 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
16 #include <linux/module.h>
17 #include <asm/uaccess.h>
18 #include <linux/bitops.h>
19 #include <linux/capability.h>
20 #include <linux/types.h>
21 #include <linux/kernel.h>
23 #include <linux/string.h>
24 #include <linux/socket.h>
25 #include <linux/sockios.h>
26 #include <linux/errno.h>
28 #include <linux/inet.h>
29 #include <linux/inetdevice.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_addr.h>
32 #include <linux/if_arp.h>
33 #include <linux/skbuff.h>
34 #include <linux/cache.h>
35 #include <linux/init.h>
36 #include <linux/list.h>
37 #include <linux/slab.h>
40 #include <net/protocol.h>
41 #include <net/route.h>
45 #include <net/ip_fib.h>
46 #include <net/rtnetlink.h>
48 #include <net/l3mdev.h>
49 #include <trace/events/fib.h>
51 #ifndef CONFIG_IP_MULTIPLE_TABLES
53 static int __net_init fib4_rules_init(struct net *net)
55 struct fib_table *local_table, *main_table;
57 main_table = fib_trie_table(RT_TABLE_MAIN, NULL);
61 local_table = fib_trie_table(RT_TABLE_LOCAL, main_table);
65 hlist_add_head_rcu(&local_table->tb_hlist,
66 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]);
67 hlist_add_head_rcu(&main_table->tb_hlist,
68 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]);
72 fib_free_table(main_table);
77 struct fib_table *fib_new_table(struct net *net, u32 id)
79 struct fib_table *tb, *alias = NULL;
84 tb = fib_get_table(net, id);
88 if (id == RT_TABLE_LOCAL)
89 alias = fib_new_table(net, RT_TABLE_MAIN);
91 tb = fib_trie_table(id, alias);
97 rcu_assign_pointer(net->ipv4.fib_main, tb);
99 case RT_TABLE_DEFAULT:
100 rcu_assign_pointer(net->ipv4.fib_default, tb);
106 h = id & (FIB_TABLE_HASHSZ - 1);
107 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
110 EXPORT_SYMBOL_GPL(fib_new_table);
112 /* caller must hold either rtnl or rcu read lock */
113 struct fib_table *fib_get_table(struct net *net, u32 id)
115 struct fib_table *tb;
116 struct hlist_head *head;
121 h = id & (FIB_TABLE_HASHSZ - 1);
123 head = &net->ipv4.fib_table_hash[h];
124 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
130 #endif /* CONFIG_IP_MULTIPLE_TABLES */
132 static void fib_replace_table(struct net *net, struct fib_table *old,
133 struct fib_table *new)
135 #ifdef CONFIG_IP_MULTIPLE_TABLES
136 switch (new->tb_id) {
138 rcu_assign_pointer(net->ipv4.fib_main, new);
140 case RT_TABLE_DEFAULT:
141 rcu_assign_pointer(net->ipv4.fib_default, new);
148 /* replace the old table in the hlist */
149 hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist);
152 int fib_unmerge(struct net *net)
154 struct fib_table *old, *new;
156 /* attempt to fetch local table if it has been allocated */
157 old = fib_get_table(net, RT_TABLE_LOCAL);
161 new = fib_trie_unmerge(old);
165 /* replace merged table with clean table */
167 fib_replace_table(net, old, new);
174 static void fib_flush(struct net *net)
179 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
180 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
181 struct hlist_node *tmp;
182 struct fib_table *tb;
184 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist)
185 flushed += fib_table_flush(net, tb);
193 * Find address type as if only "dev" was present in the system. If
194 * on_dev is NULL then all interfaces are taken into consideration.
196 static inline unsigned int __inet_dev_addr_type(struct net *net,
197 const struct net_device *dev,
198 __be32 addr, u32 tb_id)
200 struct flowi4 fl4 = { .daddr = addr };
201 struct fib_result res;
202 unsigned int ret = RTN_BROADCAST;
203 struct fib_table *table;
205 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
206 return RTN_BROADCAST;
207 if (ipv4_is_multicast(addr))
208 return RTN_MULTICAST;
212 table = fib_get_table(net, tb_id);
215 if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) {
216 if (!dev || dev == res.fi->fib_dev)
225 unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id)
227 return __inet_dev_addr_type(net, NULL, addr, tb_id);
229 EXPORT_SYMBOL(inet_addr_type_table);
231 unsigned int inet_addr_type(struct net *net, __be32 addr)
233 return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL);
235 EXPORT_SYMBOL(inet_addr_type);
237 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
240 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
242 return __inet_dev_addr_type(net, dev, addr, rt_table);
244 EXPORT_SYMBOL(inet_dev_addr_type);
246 /* inet_addr_type with dev == NULL but using the table from a dev
247 * if one is associated
249 unsigned int inet_addr_type_dev_table(struct net *net,
250 const struct net_device *dev,
253 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
255 return __inet_dev_addr_type(net, NULL, addr, rt_table);
257 EXPORT_SYMBOL(inet_addr_type_dev_table);
259 __be32 fib_compute_spec_dst(struct sk_buff *skb)
261 struct net_device *dev = skb->dev;
262 struct in_device *in_dev;
263 struct fib_result res;
268 rt = skb_rtable(skb);
269 if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) ==
271 return ip_hdr(skb)->daddr;
273 in_dev = __in_dev_get_rcu(dev);
278 scope = RT_SCOPE_UNIVERSE;
279 if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
280 struct flowi4 fl4 = {
281 .flowi4_iif = LOOPBACK_IFINDEX,
282 .daddr = ip_hdr(skb)->saddr,
283 .flowi4_tos = RT_TOS(ip_hdr(skb)->tos),
284 .flowi4_scope = scope,
285 .flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0,
287 if (!fib_lookup(net, &fl4, &res, 0))
288 return FIB_RES_PREFSRC(net, res);
290 scope = RT_SCOPE_LINK;
293 return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
296 /* Given (packet source, input interface) and optional (dst, oif, tos):
297 * - (main) check, that source is valid i.e. not broadcast or our local
299 * - figure out what "logical" interface this packet arrived
300 * and calculate "specific destination" address.
301 * - check, that packet arrived from expected physical interface.
302 * called with rcu_read_lock()
304 static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
305 u8 tos, int oif, struct net_device *dev,
306 int rpf, struct in_device *idev, u32 *itag)
309 struct fib_result res;
315 fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev);
317 fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX;
320 fl4.flowi4_tos = tos;
321 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
322 fl4.flowi4_tun_key.tun_id = 0;
323 fl4.flowi4_flags = 0;
325 no_addr = idev->ifa_list == NULL;
327 fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0;
329 trace_fib_validate_source(dev, &fl4);
332 if (fib_lookup(net, &fl4, &res, 0))
334 if (res.type != RTN_UNICAST &&
335 (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev)))
337 if (!rpf && !fib_num_tclassid_users(dev_net(dev)) &&
338 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev)))
340 fib_combine_itag(itag, &res);
343 #ifdef CONFIG_IP_ROUTE_MULTIPATH
344 for (ret = 0; ret < res.fi->fib_nhs; ret++) {
345 struct fib_nh *nh = &res.fi->fib_nh[ret];
347 if (nh->nh_dev == dev) {
350 } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) {
356 if (FIB_RES_DEV(res) == dev)
360 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
367 fl4.flowi4_oif = dev->ifindex;
370 if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) {
371 if (res.type == RTN_UNICAST)
372 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
388 /* Ignore rp_filter for packets protected by IPsec. */
389 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
390 u8 tos, int oif, struct net_device *dev,
391 struct in_device *idev, u32 *itag)
393 int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
395 if (!r && !fib_num_tclassid_users(dev_net(dev)) &&
396 IN_DEV_ACCEPT_LOCAL(idev) &&
397 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
401 return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag);
404 static inline __be32 sk_extract_addr(struct sockaddr *addr)
406 return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
409 static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
413 nla = (struct nlattr *) ((char *) mx + len);
414 nla->nla_type = type;
415 nla->nla_len = nla_attr_size(4);
416 *(u32 *) nla_data(nla) = value;
418 return len + nla_total_size(4);
421 static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
422 struct fib_config *cfg)
427 memset(cfg, 0, sizeof(*cfg));
428 cfg->fc_nlinfo.nl_net = net;
430 if (rt->rt_dst.sa_family != AF_INET)
431 return -EAFNOSUPPORT;
434 * Check mask for validity:
435 * a) it must be contiguous.
436 * b) destination must have all host bits clear.
437 * c) if application forgot to set correct family (AF_INET),
438 * reject request unless it is absolutely clear i.e.
439 * both family and mask are zero.
442 addr = sk_extract_addr(&rt->rt_dst);
443 if (!(rt->rt_flags & RTF_HOST)) {
444 __be32 mask = sk_extract_addr(&rt->rt_genmask);
446 if (rt->rt_genmask.sa_family != AF_INET) {
447 if (mask || rt->rt_genmask.sa_family)
448 return -EAFNOSUPPORT;
451 if (bad_mask(mask, addr))
454 plen = inet_mask_len(mask);
457 cfg->fc_dst_len = plen;
460 if (cmd != SIOCDELRT) {
461 cfg->fc_nlflags = NLM_F_CREATE;
462 cfg->fc_protocol = RTPROT_BOOT;
466 cfg->fc_priority = rt->rt_metric - 1;
468 if (rt->rt_flags & RTF_REJECT) {
469 cfg->fc_scope = RT_SCOPE_HOST;
470 cfg->fc_type = RTN_UNREACHABLE;
474 cfg->fc_scope = RT_SCOPE_NOWHERE;
475 cfg->fc_type = RTN_UNICAST;
479 struct net_device *dev;
480 char devname[IFNAMSIZ];
482 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
485 devname[IFNAMSIZ-1] = 0;
486 colon = strchr(devname, ':');
489 dev = __dev_get_by_name(net, devname);
492 cfg->fc_oif = dev->ifindex;
493 cfg->fc_table = l3mdev_fib_table(dev);
495 struct in_ifaddr *ifa;
496 struct in_device *in_dev = __in_dev_get_rtnl(dev);
500 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
501 if (strcmp(ifa->ifa_label, devname) == 0)
505 cfg->fc_prefsrc = ifa->ifa_local;
509 addr = sk_extract_addr(&rt->rt_gateway);
510 if (rt->rt_gateway.sa_family == AF_INET && addr) {
511 unsigned int addr_type;
514 addr_type = inet_addr_type_table(net, addr, cfg->fc_table);
515 if (rt->rt_flags & RTF_GATEWAY &&
516 addr_type == RTN_UNICAST)
517 cfg->fc_scope = RT_SCOPE_UNIVERSE;
520 if (cmd == SIOCDELRT)
523 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
526 if (cfg->fc_scope == RT_SCOPE_NOWHERE)
527 cfg->fc_scope = RT_SCOPE_LINK;
529 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
533 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
537 if (rt->rt_flags & RTF_MTU)
538 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
540 if (rt->rt_flags & RTF_WINDOW)
541 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
543 if (rt->rt_flags & RTF_IRTT)
544 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
547 cfg->fc_mx_len = len;
554 * Handle IP routing ioctl calls.
555 * These are used to manipulate the routing tables
557 int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
559 struct fib_config cfg;
564 case SIOCADDRT: /* Add a route */
565 case SIOCDELRT: /* Delete a route */
566 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
569 if (copy_from_user(&rt, arg, sizeof(rt)))
573 err = rtentry_to_fib_config(net, cmd, &rt, &cfg);
575 struct fib_table *tb;
577 if (cmd == SIOCDELRT) {
578 tb = fib_get_table(net, cfg.fc_table);
580 err = fib_table_delete(net, tb, &cfg);
584 tb = fib_new_table(net, cfg.fc_table);
586 err = fib_table_insert(net, tb, &cfg);
591 /* allocated by rtentry_to_fib_config() */
600 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
601 [RTA_DST] = { .type = NLA_U32 },
602 [RTA_SRC] = { .type = NLA_U32 },
603 [RTA_IIF] = { .type = NLA_U32 },
604 [RTA_OIF] = { .type = NLA_U32 },
605 [RTA_GATEWAY] = { .type = NLA_U32 },
606 [RTA_PRIORITY] = { .type = NLA_U32 },
607 [RTA_PREFSRC] = { .type = NLA_U32 },
608 [RTA_METRICS] = { .type = NLA_NESTED },
609 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
610 [RTA_FLOW] = { .type = NLA_U32 },
611 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
612 [RTA_ENCAP] = { .type = NLA_NESTED },
615 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
616 struct nlmsghdr *nlh, struct fib_config *cfg)
622 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
626 memset(cfg, 0, sizeof(*cfg));
628 rtm = nlmsg_data(nlh);
629 cfg->fc_dst_len = rtm->rtm_dst_len;
630 cfg->fc_tos = rtm->rtm_tos;
631 cfg->fc_table = rtm->rtm_table;
632 cfg->fc_protocol = rtm->rtm_protocol;
633 cfg->fc_scope = rtm->rtm_scope;
634 cfg->fc_type = rtm->rtm_type;
635 cfg->fc_flags = rtm->rtm_flags;
636 cfg->fc_nlflags = nlh->nlmsg_flags;
638 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
639 cfg->fc_nlinfo.nlh = nlh;
640 cfg->fc_nlinfo.nl_net = net;
642 if (cfg->fc_type > RTN_MAX) {
647 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
648 switch (nla_type(attr)) {
650 cfg->fc_dst = nla_get_be32(attr);
653 cfg->fc_oif = nla_get_u32(attr);
656 cfg->fc_gw = nla_get_be32(attr);
659 cfg->fc_priority = nla_get_u32(attr);
662 cfg->fc_prefsrc = nla_get_be32(attr);
665 cfg->fc_mx = nla_data(attr);
666 cfg->fc_mx_len = nla_len(attr);
669 cfg->fc_mp = nla_data(attr);
670 cfg->fc_mp_len = nla_len(attr);
673 cfg->fc_flow = nla_get_u32(attr);
676 cfg->fc_table = nla_get_u32(attr);
679 cfg->fc_encap = attr;
682 cfg->fc_encap_type = nla_get_u16(attr);
692 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
694 struct net *net = sock_net(skb->sk);
695 struct fib_config cfg;
696 struct fib_table *tb;
699 err = rtm_to_fib_config(net, skb, nlh, &cfg);
703 tb = fib_get_table(net, cfg.fc_table);
709 err = fib_table_delete(net, tb, &cfg);
714 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
716 struct net *net = sock_net(skb->sk);
717 struct fib_config cfg;
718 struct fib_table *tb;
721 err = rtm_to_fib_config(net, skb, nlh, &cfg);
725 tb = fib_new_table(net, cfg.fc_table);
731 err = fib_table_insert(net, tb, &cfg);
736 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
738 struct net *net = sock_net(skb->sk);
740 unsigned int e = 0, s_e;
741 struct fib_table *tb;
742 struct hlist_head *head;
745 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
746 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
754 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
756 head = &net->ipv4.fib_table_hash[h];
757 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
761 memset(&cb->args[2], 0, sizeof(cb->args) -
762 2 * sizeof(cb->args[0]));
763 if (fib_table_dump(tb, skb, cb) < 0)
779 /* Prepare and feed intra-kernel routing request.
780 * Really, it should be netlink message, but :-( netlink
781 * can be not configured, so that we feed it directly
782 * to fib engine. It is legal, because all events occur
783 * only when netlink is already locked.
785 static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
787 struct net *net = dev_net(ifa->ifa_dev->dev);
788 u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev);
789 struct fib_table *tb;
790 struct fib_config cfg = {
791 .fc_protocol = RTPROT_KERNEL,
794 .fc_dst_len = dst_len,
795 .fc_prefsrc = ifa->ifa_local,
796 .fc_oif = ifa->ifa_dev->dev->ifindex,
797 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
804 tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL;
806 tb = fib_new_table(net, tb_id);
810 cfg.fc_table = tb->tb_id;
812 if (type != RTN_LOCAL)
813 cfg.fc_scope = RT_SCOPE_LINK;
815 cfg.fc_scope = RT_SCOPE_HOST;
817 if (cmd == RTM_NEWROUTE)
818 fib_table_insert(net, tb, &cfg);
820 fib_table_delete(net, tb, &cfg);
823 void fib_add_ifaddr(struct in_ifaddr *ifa)
825 struct in_device *in_dev = ifa->ifa_dev;
826 struct net_device *dev = in_dev->dev;
827 struct in_ifaddr *prim = ifa;
828 __be32 mask = ifa->ifa_mask;
829 __be32 addr = ifa->ifa_local;
830 __be32 prefix = ifa->ifa_address & mask;
832 if (ifa->ifa_flags & IFA_F_SECONDARY) {
833 prim = inet_ifa_byprefix(in_dev, prefix, mask);
835 pr_warn("%s: bug: prim == NULL\n", __func__);
840 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
842 if (!(dev->flags & IFF_UP))
845 /* Add broadcast address, if it is explicitly assigned. */
846 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
847 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
849 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
850 (prefix != addr || ifa->ifa_prefixlen < 32)) {
851 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
852 fib_magic(RTM_NEWROUTE,
853 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
854 prefix, ifa->ifa_prefixlen, prim);
856 /* Add network specific broadcasts, when it takes a sense */
857 if (ifa->ifa_prefixlen < 31) {
858 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
859 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
865 /* Delete primary or secondary address.
866 * Optionally, on secondary address promotion consider the addresses
867 * from subnet iprim as deleted, even if they are in device list.
868 * In this case the secondary ifa can be in device list.
870 void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
872 struct in_device *in_dev = ifa->ifa_dev;
873 struct net_device *dev = in_dev->dev;
874 struct in_ifaddr *ifa1;
875 struct in_ifaddr *prim = ifa, *prim1 = NULL;
876 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
877 __be32 any = ifa->ifa_address & ifa->ifa_mask;
883 int subnet = 0; /* Primary network */
884 int gone = 1; /* Address is missing */
885 int same_prefsrc = 0; /* Another primary with same IP */
887 if (ifa->ifa_flags & IFA_F_SECONDARY) {
888 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
890 /* if the device has been deleted, we don't perform
894 pr_warn("%s: bug: prim == NULL\n", __func__);
897 if (iprim && iprim != prim) {
898 pr_warn("%s: bug: iprim != prim\n", __func__);
901 } else if (!ipv4_is_zeronet(any) &&
902 (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
903 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
904 fib_magic(RTM_DELROUTE,
905 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
906 any, ifa->ifa_prefixlen, prim);
913 /* Deletion is more complicated than add.
914 * We should take care of not to delete too much :-)
916 * Scan address list to be sure that addresses are really gone.
919 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
921 /* promotion, keep the IP */
925 /* Ignore IFAs from our subnet */
926 if (iprim && ifa1->ifa_mask == iprim->ifa_mask &&
927 inet_ifa_match(ifa1->ifa_address, iprim))
930 /* Ignore ifa1 if it uses different primary IP (prefsrc) */
931 if (ifa1->ifa_flags & IFA_F_SECONDARY) {
932 /* Another address from our subnet? */
933 if (ifa1->ifa_mask == prim->ifa_mask &&
934 inet_ifa_match(ifa1->ifa_address, prim))
937 /* We reached the secondaries, so
938 * same_prefsrc should be determined.
942 /* Search new prim1 if ifa1 is not
943 * using the current prim1
946 ifa1->ifa_mask != prim1->ifa_mask ||
947 !inet_ifa_match(ifa1->ifa_address, prim1))
948 prim1 = inet_ifa_byprefix(in_dev,
953 if (prim1->ifa_local != prim->ifa_local)
957 if (prim->ifa_local != ifa1->ifa_local)
963 if (ifa->ifa_local == ifa1->ifa_local)
965 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
967 if (brd == ifa1->ifa_broadcast)
969 if (any == ifa1->ifa_broadcast)
971 /* primary has network specific broadcasts */
972 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) {
973 __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask;
974 __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask;
976 if (!ipv4_is_zeronet(any1)) {
977 if (ifa->ifa_broadcast == brd1 ||
978 ifa->ifa_broadcast == any1)
980 if (brd == brd1 || brd == any1)
982 if (any == brd1 || any == any1)
990 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
991 if (subnet && ifa->ifa_prefixlen < 31) {
993 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
995 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
997 if (!(ok & LOCAL_OK)) {
998 unsigned int addr_type;
1000 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
1002 /* Check, that this local address finally disappeared. */
1003 addr_type = inet_addr_type_dev_table(dev_net(dev), dev,
1005 if (gone && addr_type != RTN_LOCAL) {
1006 /* And the last, but not the least thing.
1007 * We must flush stray FIB entries.
1009 * First of all, we scan fib_info list searching
1010 * for stray nexthop entries, then ignite fib_flush.
1012 if (fib_sync_down_addr(dev, ifa->ifa_local))
1013 fib_flush(dev_net(dev));
1022 static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn)
1025 struct fib_result res;
1026 struct flowi4 fl4 = {
1027 .flowi4_mark = frn->fl_mark,
1028 .daddr = frn->fl_addr,
1029 .flowi4_tos = frn->fl_tos,
1030 .flowi4_scope = frn->fl_scope,
1032 struct fib_table *tb;
1036 tb = fib_get_table(net, frn->tb_id_in);
1042 frn->tb_id = tb->tb_id;
1043 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
1046 frn->prefixlen = res.prefixlen;
1047 frn->nh_sel = res.nh_sel;
1048 frn->type = res.type;
1049 frn->scope = res.scope;
1057 static void nl_fib_input(struct sk_buff *skb)
1060 struct fib_result_nl *frn;
1061 struct nlmsghdr *nlh;
1064 net = sock_net(skb->sk);
1065 nlh = nlmsg_hdr(skb);
1066 if (skb->len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len ||
1067 nlmsg_len(nlh) < sizeof(*frn))
1070 skb = netlink_skb_clone(skb, GFP_KERNEL);
1073 nlh = nlmsg_hdr(skb);
1075 frn = (struct fib_result_nl *) nlmsg_data(nlh);
1076 nl_fib_lookup(net, frn);
1078 portid = NETLINK_CB(skb).portid; /* netlink portid */
1079 NETLINK_CB(skb).portid = 0; /* from kernel */
1080 NETLINK_CB(skb).dst_group = 0; /* unicast */
1081 netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT);
1084 static int __net_init nl_fib_lookup_init(struct net *net)
1087 struct netlink_kernel_cfg cfg = {
1088 .input = nl_fib_input,
1091 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg);
1093 return -EAFNOSUPPORT;
1094 net->ipv4.fibnl = sk;
1098 static void nl_fib_lookup_exit(struct net *net)
1100 netlink_kernel_release(net->ipv4.fibnl);
1101 net->ipv4.fibnl = NULL;
1104 static void fib_disable_ip(struct net_device *dev, unsigned long event,
1107 if (fib_sync_down_dev(dev, event, force))
1108 fib_flush(dev_net(dev));
1109 rt_cache_flush(dev_net(dev));
1113 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
1115 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
1116 struct net_device *dev = ifa->ifa_dev->dev;
1117 struct net *net = dev_net(dev);
1121 fib_add_ifaddr(ifa);
1122 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1123 fib_sync_up(dev, RTNH_F_DEAD);
1125 atomic_inc(&net->ipv4.dev_addr_genid);
1126 rt_cache_flush(dev_net(dev));
1129 fib_del_ifaddr(ifa, NULL);
1130 atomic_inc(&net->ipv4.dev_addr_genid);
1131 if (!ifa->ifa_dev->ifa_list) {
1132 /* Last address was deleted from this interface.
1135 fib_disable_ip(dev, event, true);
1137 rt_cache_flush(dev_net(dev));
1144 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1146 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1147 struct netdev_notifier_changeupper_info *info;
1148 struct in_device *in_dev;
1149 struct net *net = dev_net(dev);
1152 if (event == NETDEV_UNREGISTER) {
1153 fib_disable_ip(dev, event, true);
1158 in_dev = __in_dev_get_rtnl(dev);
1165 fib_add_ifaddr(ifa);
1166 } endfor_ifa(in_dev);
1167 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1168 fib_sync_up(dev, RTNH_F_DEAD);
1170 atomic_inc(&net->ipv4.dev_addr_genid);
1171 rt_cache_flush(net);
1174 fib_disable_ip(dev, event, false);
1177 flags = dev_get_flags(dev);
1178 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1179 fib_sync_up(dev, RTNH_F_LINKDOWN);
1181 fib_sync_down_dev(dev, event, false);
1183 case NETDEV_CHANGEMTU:
1184 rt_cache_flush(net);
1186 case NETDEV_CHANGEUPPER:
1188 /* flush all routes if dev is linked to or unlinked from
1189 * an L3 master device (e.g., VRF)
1191 if (info->upper_dev && netif_is_l3_master(info->upper_dev))
1192 fib_disable_ip(dev, NETDEV_DOWN, true);
1198 static struct notifier_block fib_inetaddr_notifier = {
1199 .notifier_call = fib_inetaddr_event,
1202 static struct notifier_block fib_netdev_notifier = {
1203 .notifier_call = fib_netdev_event,
1206 static int __net_init ip_fib_net_init(struct net *net)
1209 size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ;
1211 /* Avoid false sharing : Use at least a full cache line */
1212 size = max_t(size_t, size, L1_CACHE_BYTES);
1214 net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL);
1215 if (!net->ipv4.fib_table_hash)
1218 err = fib4_rules_init(net);
1224 kfree(net->ipv4.fib_table_hash);
1228 static void ip_fib_net_exit(struct net *net)
1233 #ifdef CONFIG_IP_MULTIPLE_TABLES
1234 RCU_INIT_POINTER(net->ipv4.fib_main, NULL);
1235 RCU_INIT_POINTER(net->ipv4.fib_default, NULL);
1237 for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
1238 struct hlist_head *head = &net->ipv4.fib_table_hash[i];
1239 struct hlist_node *tmp;
1240 struct fib_table *tb;
1242 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) {
1243 hlist_del(&tb->tb_hlist);
1244 fib_table_flush(net, tb);
1249 #ifdef CONFIG_IP_MULTIPLE_TABLES
1250 fib4_rules_exit(net);
1253 kfree(net->ipv4.fib_table_hash);
1256 static int __net_init fib_net_init(struct net *net)
1260 #ifdef CONFIG_IP_ROUTE_CLASSID
1261 net->ipv4.fib_num_tclassid_users = 0;
1263 error = ip_fib_net_init(net);
1266 error = nl_fib_lookup_init(net);
1269 error = fib_proc_init(net);
1276 nl_fib_lookup_exit(net);
1278 ip_fib_net_exit(net);
1282 static void __net_exit fib_net_exit(struct net *net)
1285 nl_fib_lookup_exit(net);
1286 ip_fib_net_exit(net);
1289 static struct pernet_operations fib_net_ops = {
1290 .init = fib_net_init,
1291 .exit = fib_net_exit,
1294 void __init ip_fib_init(void)
1296 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL);
1297 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL);
1298 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL);
1300 register_pernet_subsys(&fib_net_ops);
1301 register_netdevice_notifier(&fib_netdev_notifier);
1302 register_inetaddr_notifier(&fib_inetaddr_notifier);