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 <asm/system.h>
19 #include <linux/bitops.h>
20 #include <linux/capability.h>
21 #include <linux/types.h>
22 #include <linux/kernel.h>
24 #include <linux/string.h>
25 #include <linux/socket.h>
26 #include <linux/sockios.h>
27 #include <linux/errno.h>
29 #include <linux/inet.h>
30 #include <linux/inetdevice.h>
31 #include <linux/netdevice.h>
32 #include <linux/if_addr.h>
33 #include <linux/if_arp.h>
34 #include <linux/skbuff.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>
49 #ifndef CONFIG_IP_MULTIPLE_TABLES
51 static int __net_init fib4_rules_init(struct net *net)
53 struct fib_table *local_table, *main_table;
55 local_table = fib_trie_table(RT_TABLE_LOCAL);
56 if (local_table == NULL)
59 main_table = fib_trie_table(RT_TABLE_MAIN);
60 if (main_table == NULL)
63 hlist_add_head_rcu(&local_table->tb_hlist,
64 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]);
65 hlist_add_head_rcu(&main_table->tb_hlist,
66 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]);
75 struct fib_table *fib_new_table(struct net *net, u32 id)
82 tb = fib_get_table(net, id);
86 tb = fib_trie_table(id);
89 h = id & (FIB_TABLE_HASHSZ - 1);
90 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
94 struct fib_table *fib_get_table(struct net *net, u32 id)
97 struct hlist_node *node;
98 struct hlist_head *head;
103 h = id & (FIB_TABLE_HASHSZ - 1);
106 head = &net->ipv4.fib_table_hash[h];
107 hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
108 if (tb->tb_id == id) {
116 #endif /* CONFIG_IP_MULTIPLE_TABLES */
118 static void fib_flush(struct net *net)
121 struct fib_table *tb;
122 struct hlist_node *node;
123 struct hlist_head *head;
126 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
127 head = &net->ipv4.fib_table_hash[h];
128 hlist_for_each_entry(tb, node, head, tb_hlist)
129 flushed += fib_table_flush(tb);
133 rt_cache_flush(net, -1);
137 * Find address type as if only "dev" was present in the system. If
138 * on_dev is NULL then all interfaces are taken into consideration.
140 static inline unsigned __inet_dev_addr_type(struct net *net,
141 const struct net_device *dev,
144 struct flowi4 fl4 = { .daddr = addr };
145 struct fib_result res;
146 unsigned ret = RTN_BROADCAST;
147 struct fib_table *local_table;
149 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
150 return RTN_BROADCAST;
151 if (ipv4_is_multicast(addr))
152 return RTN_MULTICAST;
154 #ifdef CONFIG_IP_MULTIPLE_TABLES
158 local_table = fib_get_table(net, RT_TABLE_LOCAL);
162 if (!fib_table_lookup(local_table, &fl4, &res, FIB_LOOKUP_NOREF)) {
163 if (!dev || dev == res.fi->fib_dev)
171 unsigned int inet_addr_type(struct net *net, __be32 addr)
173 return __inet_dev_addr_type(net, NULL, addr);
175 EXPORT_SYMBOL(inet_addr_type);
177 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
180 return __inet_dev_addr_type(net, dev, addr);
182 EXPORT_SYMBOL(inet_dev_addr_type);
184 /* Given (packet source, input interface) and optional (dst, oif, tos):
185 * - (main) check, that source is valid i.e. not broadcast or our local
187 * - figure out what "logical" interface this packet arrived
188 * and calculate "specific destination" address.
189 * - check, that packet arrived from expected physical interface.
190 * called with rcu_read_lock()
192 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, u8 tos,
193 int oif, struct net_device *dev, __be32 *spec_dst,
196 struct in_device *in_dev;
198 struct fib_result res;
199 int no_addr, rpf, accept_local;
205 fl4.flowi4_iif = oif;
208 fl4.flowi4_tos = tos;
209 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
211 no_addr = rpf = accept_local = 0;
212 in_dev = __in_dev_get_rcu(dev);
214 no_addr = in_dev->ifa_list == NULL;
216 /* Ignore rp_filter for packets protected by IPsec. */
217 rpf = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(in_dev);
219 accept_local = IN_DEV_ACCEPT_LOCAL(in_dev);
220 fl4.flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0;
227 if (fib_lookup(net, &fl4, &res))
229 if (res.type != RTN_UNICAST) {
230 if (res.type != RTN_LOCAL || !accept_local)
233 *spec_dst = FIB_RES_PREFSRC(net, res);
234 fib_combine_itag(itag, &res);
237 #ifdef CONFIG_IP_ROUTE_MULTIPATH
238 for (ret = 0; ret < res.fi->fib_nhs; ret++) {
239 struct fib_nh *nh = &res.fi->fib_nh[ret];
241 if (nh->nh_dev == dev) {
247 if (FIB_RES_DEV(res) == dev)
251 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
258 fl4.flowi4_oif = dev->ifindex;
261 if (fib_lookup(net, &fl4, &res) == 0) {
262 if (res.type == RTN_UNICAST) {
263 *spec_dst = FIB_RES_PREFSRC(net, res);
264 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
272 *spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
282 static inline __be32 sk_extract_addr(struct sockaddr *addr)
284 return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
287 static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
291 nla = (struct nlattr *) ((char *) mx + len);
292 nla->nla_type = type;
293 nla->nla_len = nla_attr_size(4);
294 *(u32 *) nla_data(nla) = value;
296 return len + nla_total_size(4);
299 static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
300 struct fib_config *cfg)
305 memset(cfg, 0, sizeof(*cfg));
306 cfg->fc_nlinfo.nl_net = net;
308 if (rt->rt_dst.sa_family != AF_INET)
309 return -EAFNOSUPPORT;
312 * Check mask for validity:
313 * a) it must be contiguous.
314 * b) destination must have all host bits clear.
315 * c) if application forgot to set correct family (AF_INET),
316 * reject request unless it is absolutely clear i.e.
317 * both family and mask are zero.
320 addr = sk_extract_addr(&rt->rt_dst);
321 if (!(rt->rt_flags & RTF_HOST)) {
322 __be32 mask = sk_extract_addr(&rt->rt_genmask);
324 if (rt->rt_genmask.sa_family != AF_INET) {
325 if (mask || rt->rt_genmask.sa_family)
326 return -EAFNOSUPPORT;
329 if (bad_mask(mask, addr))
332 plen = inet_mask_len(mask);
335 cfg->fc_dst_len = plen;
338 if (cmd != SIOCDELRT) {
339 cfg->fc_nlflags = NLM_F_CREATE;
340 cfg->fc_protocol = RTPROT_BOOT;
344 cfg->fc_priority = rt->rt_metric - 1;
346 if (rt->rt_flags & RTF_REJECT) {
347 cfg->fc_scope = RT_SCOPE_HOST;
348 cfg->fc_type = RTN_UNREACHABLE;
352 cfg->fc_scope = RT_SCOPE_NOWHERE;
353 cfg->fc_type = RTN_UNICAST;
357 struct net_device *dev;
358 char devname[IFNAMSIZ];
360 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
363 devname[IFNAMSIZ-1] = 0;
364 colon = strchr(devname, ':');
367 dev = __dev_get_by_name(net, devname);
370 cfg->fc_oif = dev->ifindex;
372 struct in_ifaddr *ifa;
373 struct in_device *in_dev = __in_dev_get_rtnl(dev);
377 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
378 if (strcmp(ifa->ifa_label, devname) == 0)
382 cfg->fc_prefsrc = ifa->ifa_local;
386 addr = sk_extract_addr(&rt->rt_gateway);
387 if (rt->rt_gateway.sa_family == AF_INET && addr) {
389 if (rt->rt_flags & RTF_GATEWAY &&
390 inet_addr_type(net, addr) == RTN_UNICAST)
391 cfg->fc_scope = RT_SCOPE_UNIVERSE;
394 if (cmd == SIOCDELRT)
397 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
400 if (cfg->fc_scope == RT_SCOPE_NOWHERE)
401 cfg->fc_scope = RT_SCOPE_LINK;
403 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
407 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
411 if (rt->rt_flags & RTF_MTU)
412 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
414 if (rt->rt_flags & RTF_WINDOW)
415 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
417 if (rt->rt_flags & RTF_IRTT)
418 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
421 cfg->fc_mx_len = len;
428 * Handle IP routing ioctl calls.
429 * These are used to manipulate the routing tables
431 int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
433 struct fib_config cfg;
438 case SIOCADDRT: /* Add a route */
439 case SIOCDELRT: /* Delete a route */
440 if (!capable(CAP_NET_ADMIN))
443 if (copy_from_user(&rt, arg, sizeof(rt)))
447 err = rtentry_to_fib_config(net, cmd, &rt, &cfg);
449 struct fib_table *tb;
451 if (cmd == SIOCDELRT) {
452 tb = fib_get_table(net, cfg.fc_table);
454 err = fib_table_delete(tb, &cfg);
458 tb = fib_new_table(net, cfg.fc_table);
460 err = fib_table_insert(tb, &cfg);
465 /* allocated by rtentry_to_fib_config() */
474 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
475 [RTA_DST] = { .type = NLA_U32 },
476 [RTA_SRC] = { .type = NLA_U32 },
477 [RTA_IIF] = { .type = NLA_U32 },
478 [RTA_OIF] = { .type = NLA_U32 },
479 [RTA_GATEWAY] = { .type = NLA_U32 },
480 [RTA_PRIORITY] = { .type = NLA_U32 },
481 [RTA_PREFSRC] = { .type = NLA_U32 },
482 [RTA_METRICS] = { .type = NLA_NESTED },
483 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
484 [RTA_FLOW] = { .type = NLA_U32 },
487 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
488 struct nlmsghdr *nlh, struct fib_config *cfg)
494 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
498 memset(cfg, 0, sizeof(*cfg));
500 rtm = nlmsg_data(nlh);
501 cfg->fc_dst_len = rtm->rtm_dst_len;
502 cfg->fc_tos = rtm->rtm_tos;
503 cfg->fc_table = rtm->rtm_table;
504 cfg->fc_protocol = rtm->rtm_protocol;
505 cfg->fc_scope = rtm->rtm_scope;
506 cfg->fc_type = rtm->rtm_type;
507 cfg->fc_flags = rtm->rtm_flags;
508 cfg->fc_nlflags = nlh->nlmsg_flags;
510 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
511 cfg->fc_nlinfo.nlh = nlh;
512 cfg->fc_nlinfo.nl_net = net;
514 if (cfg->fc_type > RTN_MAX) {
519 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
520 switch (nla_type(attr)) {
522 cfg->fc_dst = nla_get_be32(attr);
525 cfg->fc_oif = nla_get_u32(attr);
528 cfg->fc_gw = nla_get_be32(attr);
531 cfg->fc_priority = nla_get_u32(attr);
534 cfg->fc_prefsrc = nla_get_be32(attr);
537 cfg->fc_mx = nla_data(attr);
538 cfg->fc_mx_len = nla_len(attr);
541 cfg->fc_mp = nla_data(attr);
542 cfg->fc_mp_len = nla_len(attr);
545 cfg->fc_flow = nla_get_u32(attr);
548 cfg->fc_table = nla_get_u32(attr);
558 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
560 struct net *net = sock_net(skb->sk);
561 struct fib_config cfg;
562 struct fib_table *tb;
565 err = rtm_to_fib_config(net, skb, nlh, &cfg);
569 tb = fib_get_table(net, cfg.fc_table);
575 err = fib_table_delete(tb, &cfg);
580 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
582 struct net *net = sock_net(skb->sk);
583 struct fib_config cfg;
584 struct fib_table *tb;
587 err = rtm_to_fib_config(net, skb, nlh, &cfg);
591 tb = fib_new_table(net, cfg.fc_table);
597 err = fib_table_insert(tb, &cfg);
602 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
604 struct net *net = sock_net(skb->sk);
606 unsigned int e = 0, s_e;
607 struct fib_table *tb;
608 struct hlist_node *node;
609 struct hlist_head *head;
612 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
613 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
614 return ip_rt_dump(skb, cb);
619 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
621 head = &net->ipv4.fib_table_hash[h];
622 hlist_for_each_entry(tb, node, head, tb_hlist) {
626 memset(&cb->args[2], 0, sizeof(cb->args) -
627 2 * sizeof(cb->args[0]));
628 if (fib_table_dump(tb, skb, cb) < 0)
642 /* Prepare and feed intra-kernel routing request.
643 * Really, it should be netlink message, but :-( netlink
644 * can be not configured, so that we feed it directly
645 * to fib engine. It is legal, because all events occur
646 * only when netlink is already locked.
648 static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
650 struct net *net = dev_net(ifa->ifa_dev->dev);
651 struct fib_table *tb;
652 struct fib_config cfg = {
653 .fc_protocol = RTPROT_KERNEL,
656 .fc_dst_len = dst_len,
657 .fc_prefsrc = ifa->ifa_local,
658 .fc_oif = ifa->ifa_dev->dev->ifindex,
659 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
665 if (type == RTN_UNICAST)
666 tb = fib_new_table(net, RT_TABLE_MAIN);
668 tb = fib_new_table(net, RT_TABLE_LOCAL);
673 cfg.fc_table = tb->tb_id;
675 if (type != RTN_LOCAL)
676 cfg.fc_scope = RT_SCOPE_LINK;
678 cfg.fc_scope = RT_SCOPE_HOST;
680 if (cmd == RTM_NEWROUTE)
681 fib_table_insert(tb, &cfg);
683 fib_table_delete(tb, &cfg);
686 void fib_add_ifaddr(struct in_ifaddr *ifa)
688 struct in_device *in_dev = ifa->ifa_dev;
689 struct net_device *dev = in_dev->dev;
690 struct in_ifaddr *prim = ifa;
691 __be32 mask = ifa->ifa_mask;
692 __be32 addr = ifa->ifa_local;
693 __be32 prefix = ifa->ifa_address & mask;
695 if (ifa->ifa_flags & IFA_F_SECONDARY) {
696 prim = inet_ifa_byprefix(in_dev, prefix, mask);
698 printk(KERN_WARNING "fib_add_ifaddr: bug: prim == NULL\n");
703 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
705 if (!(dev->flags & IFF_UP))
708 /* Add broadcast address, if it is explicitly assigned. */
709 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
710 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
712 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
713 (prefix != addr || ifa->ifa_prefixlen < 32)) {
714 fib_magic(RTM_NEWROUTE,
715 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
716 prefix, ifa->ifa_prefixlen, prim);
718 /* Add network specific broadcasts, when it takes a sense */
719 if (ifa->ifa_prefixlen < 31) {
720 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
721 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
727 /* Delete primary or secondary address.
728 * Optionally, on secondary address promotion consider the addresses
729 * from subnet iprim as deleted, even if they are in device list.
730 * In this case the secondary ifa can be in device list.
732 void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
734 struct in_device *in_dev = ifa->ifa_dev;
735 struct net_device *dev = in_dev->dev;
736 struct in_ifaddr *ifa1;
737 struct in_ifaddr *prim = ifa, *prim1 = NULL;
738 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
739 __be32 any = ifa->ifa_address & ifa->ifa_mask;
745 int subnet = 0; /* Primary network */
746 int gone = 1; /* Address is missing */
747 int same_prefsrc = 0; /* Another primary with same IP */
749 if (ifa->ifa_flags & IFA_F_SECONDARY) {
750 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
752 printk(KERN_WARNING "fib_del_ifaddr: bug: prim == NULL\n");
755 if (iprim && iprim != prim) {
756 printk(KERN_WARNING "fib_del_ifaddr: bug: iprim != prim\n");
759 } else if (!ipv4_is_zeronet(any) &&
760 (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
761 fib_magic(RTM_DELROUTE,
762 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
763 any, ifa->ifa_prefixlen, prim);
767 /* Deletion is more complicated than add.
768 * We should take care of not to delete too much :-)
770 * Scan address list to be sure that addresses are really gone.
773 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
775 /* promotion, keep the IP */
779 /* Ignore IFAs from our subnet */
780 if (iprim && ifa1->ifa_mask == iprim->ifa_mask &&
781 inet_ifa_match(ifa1->ifa_address, iprim))
784 /* Ignore ifa1 if it uses different primary IP (prefsrc) */
785 if (ifa1->ifa_flags & IFA_F_SECONDARY) {
786 /* Another address from our subnet? */
787 if (ifa1->ifa_mask == prim->ifa_mask &&
788 inet_ifa_match(ifa1->ifa_address, prim))
791 /* We reached the secondaries, so
792 * same_prefsrc should be determined.
796 /* Search new prim1 if ifa1 is not
797 * using the current prim1
800 ifa1->ifa_mask != prim1->ifa_mask ||
801 !inet_ifa_match(ifa1->ifa_address, prim1))
802 prim1 = inet_ifa_byprefix(in_dev,
807 if (prim1->ifa_local != prim->ifa_local)
811 if (prim->ifa_local != ifa1->ifa_local)
817 if (ifa->ifa_local == ifa1->ifa_local)
819 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
821 if (brd == ifa1->ifa_broadcast)
823 if (any == ifa1->ifa_broadcast)
825 /* primary has network specific broadcasts */
826 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) {
827 __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask;
828 __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask;
830 if (!ipv4_is_zeronet(any1)) {
831 if (ifa->ifa_broadcast == brd1 ||
832 ifa->ifa_broadcast == any1)
834 if (brd == brd1 || brd == any1)
836 if (any == brd1 || any == any1)
843 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
844 if (subnet && ifa->ifa_prefixlen < 31) {
846 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
848 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
850 if (!(ok & LOCAL_OK)) {
851 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
853 /* Check, that this local address finally disappeared. */
855 inet_addr_type(dev_net(dev), ifa->ifa_local) != RTN_LOCAL) {
856 /* And the last, but not the least thing.
857 * We must flush stray FIB entries.
859 * First of all, we scan fib_info list searching
860 * for stray nexthop entries, then ignite fib_flush.
862 if (fib_sync_down_addr(dev_net(dev), ifa->ifa_local))
863 fib_flush(dev_net(dev));
872 static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb)
875 struct fib_result res;
876 struct flowi4 fl4 = {
877 .flowi4_mark = frn->fl_mark,
878 .daddr = frn->fl_addr,
879 .flowi4_tos = frn->fl_tos,
880 .flowi4_scope = frn->fl_scope,
883 #ifdef CONFIG_IP_MULTIPLE_TABLES
891 frn->tb_id = tb->tb_id;
893 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
896 frn->prefixlen = res.prefixlen;
897 frn->nh_sel = res.nh_sel;
898 frn->type = res.type;
899 frn->scope = res.scope;
906 static void nl_fib_input(struct sk_buff *skb)
909 struct fib_result_nl *frn;
910 struct nlmsghdr *nlh;
911 struct fib_table *tb;
914 net = sock_net(skb->sk);
915 nlh = nlmsg_hdr(skb);
916 if (skb->len < NLMSG_SPACE(0) || skb->len < nlh->nlmsg_len ||
917 nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*frn)))
920 skb = skb_clone(skb, GFP_KERNEL);
923 nlh = nlmsg_hdr(skb);
925 frn = (struct fib_result_nl *) NLMSG_DATA(nlh);
926 tb = fib_get_table(net, frn->tb_id_in);
928 nl_fib_lookup(frn, tb);
930 pid = NETLINK_CB(skb).pid; /* pid of sending process */
931 NETLINK_CB(skb).pid = 0; /* from kernel */
932 NETLINK_CB(skb).dst_group = 0; /* unicast */
933 netlink_unicast(net->ipv4.fibnl, skb, pid, MSG_DONTWAIT);
936 static int __net_init nl_fib_lookup_init(struct net *net)
939 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, 0,
940 nl_fib_input, NULL, THIS_MODULE);
942 return -EAFNOSUPPORT;
943 net->ipv4.fibnl = sk;
947 static void nl_fib_lookup_exit(struct net *net)
949 netlink_kernel_release(net->ipv4.fibnl);
950 net->ipv4.fibnl = NULL;
953 static void fib_disable_ip(struct net_device *dev, int force, int delay)
955 if (fib_sync_down_dev(dev, force))
956 fib_flush(dev_net(dev));
957 rt_cache_flush(dev_net(dev), delay);
961 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
963 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
964 struct net_device *dev = ifa->ifa_dev->dev;
965 struct net *net = dev_net(dev);
970 #ifdef CONFIG_IP_ROUTE_MULTIPATH
973 atomic_inc(&net->ipv4.dev_addr_genid);
974 rt_cache_flush(dev_net(dev), -1);
977 fib_del_ifaddr(ifa, NULL);
978 atomic_inc(&net->ipv4.dev_addr_genid);
979 if (ifa->ifa_dev->ifa_list == NULL) {
980 /* Last address was deleted from this interface.
983 fib_disable_ip(dev, 1, 0);
985 rt_cache_flush(dev_net(dev), -1);
992 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
994 struct net_device *dev = ptr;
995 struct in_device *in_dev = __in_dev_get_rtnl(dev);
996 struct net *net = dev_net(dev);
998 if (event == NETDEV_UNREGISTER) {
999 fib_disable_ip(dev, 2, -1);
1009 fib_add_ifaddr(ifa);
1010 } endfor_ifa(in_dev);
1011 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1014 atomic_inc(&net->ipv4.dev_addr_genid);
1015 rt_cache_flush(dev_net(dev), -1);
1018 fib_disable_ip(dev, 0, 0);
1020 case NETDEV_CHANGEMTU:
1022 rt_cache_flush(dev_net(dev), 0);
1024 case NETDEV_UNREGISTER_BATCH:
1025 /* The batch unregister is only called on the first
1026 * device in the list of devices being unregistered.
1027 * Therefore we should not pass dev_net(dev) in here.
1029 rt_cache_flush_batch(NULL);
1035 static struct notifier_block fib_inetaddr_notifier = {
1036 .notifier_call = fib_inetaddr_event,
1039 static struct notifier_block fib_netdev_notifier = {
1040 .notifier_call = fib_netdev_event,
1043 static int __net_init ip_fib_net_init(struct net *net)
1046 size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ;
1048 /* Avoid false sharing : Use at least a full cache line */
1049 size = max_t(size_t, size, L1_CACHE_BYTES);
1051 net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL);
1052 if (net->ipv4.fib_table_hash == NULL)
1055 err = fib4_rules_init(net);
1061 kfree(net->ipv4.fib_table_hash);
1065 static void ip_fib_net_exit(struct net *net)
1069 #ifdef CONFIG_IP_MULTIPLE_TABLES
1070 fib4_rules_exit(net);
1074 for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
1075 struct fib_table *tb;
1076 struct hlist_head *head;
1077 struct hlist_node *node, *tmp;
1079 head = &net->ipv4.fib_table_hash[i];
1080 hlist_for_each_entry_safe(tb, node, tmp, head, tb_hlist) {
1082 fib_table_flush(tb);
1087 kfree(net->ipv4.fib_table_hash);
1090 static int __net_init fib_net_init(struct net *net)
1094 error = ip_fib_net_init(net);
1097 error = nl_fib_lookup_init(net);
1100 error = fib_proc_init(net);
1107 nl_fib_lookup_exit(net);
1109 ip_fib_net_exit(net);
1113 static void __net_exit fib_net_exit(struct net *net)
1116 nl_fib_lookup_exit(net);
1117 ip_fib_net_exit(net);
1120 static struct pernet_operations fib_net_ops = {
1121 .init = fib_net_init,
1122 .exit = fib_net_exit,
1125 void __init ip_fib_init(void)
1127 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL);
1128 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL);
1129 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib);
1131 register_pernet_subsys(&fib_net_ops);
1132 register_netdevice_notifier(&fib_netdev_notifier);
1133 register_inetaddr_notifier(&fib_inetaddr_notifier);