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 * ROUTE - implementation of the IP router.
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
11 * Linus Torvalds, <Linus.Torvalds@helsinki.fi>
12 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
15 * Alan Cox : Verify area fixes.
16 * Alan Cox : cli() protects routing changes
17 * Rui Oliveira : ICMP routing table updates
18 * (rco@di.uminho.pt) Routing table insertion and update
19 * Linus Torvalds : Rewrote bits to be sensible
20 * Alan Cox : Added BSD route gw semantics
21 * Alan Cox : Super /proc >4K
22 * Alan Cox : MTU in route table
23 * Alan Cox : MSS actually. Also added the window
25 * Sam Lantinga : Fixed route matching in rt_del()
26 * Alan Cox : Routing cache support.
27 * Alan Cox : Removed compatibility cruft.
28 * Alan Cox : RTF_REJECT support.
29 * Alan Cox : TCP irtt support.
30 * Jonathan Naylor : Added Metric support.
31 * Miquel van Smoorenburg : BSD API fixes.
32 * Miquel van Smoorenburg : Metrics.
33 * Alan Cox : Use __u32 properly
34 * Alan Cox : Aligned routing errors more closely with BSD
35 * our system is still very different.
36 * Alan Cox : Faster /proc handling
37 * Alexey Kuznetsov : Massive rework to support tree based routing,
38 * routing caches and better behaviour.
40 * Olaf Erb : irtt wasn't being copied right.
41 * Bjorn Ekwall : Kerneld route support.
42 * Alan Cox : Multicast fixed (I hope)
43 * Pavel Krauz : Limited broadcast fixed
44 * Mike McLagan : Routing by source
45 * Alexey Kuznetsov : End of old history. Split to fib.c and
46 * route.c and rewritten from scratch.
47 * Andi Kleen : Load-limit warning messages.
48 * Vitaly E. Lavrov : Transparent proxy revived after year coma.
49 * Vitaly E. Lavrov : Race condition in ip_route_input_slow.
50 * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow.
51 * Vladimir V. Ivanov : IP rule info (flowid) is really useful.
52 * Marc Boucher : routing by fwmark
53 * Robert Olsson : Added rt_cache statistics
54 * Arnaldo C. Melo : Convert proc stuff to seq_file
55 * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes.
56 * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect
57 * Ilia Sotnikov : Removed TOS from hash calculations
59 * This program is free software; you can redistribute it and/or
60 * modify it under the terms of the GNU General Public License
61 * as published by the Free Software Foundation; either version
62 * 2 of the License, or (at your option) any later version.
65 #define pr_fmt(fmt) "IPv4: " fmt
67 #include <linux/module.h>
68 #include <asm/uaccess.h>
69 #include <linux/bitops.h>
70 #include <linux/types.h>
71 #include <linux/kernel.h>
73 #include <linux/bootmem.h>
74 #include <linux/string.h>
75 #include <linux/socket.h>
76 #include <linux/sockios.h>
77 #include <linux/errno.h>
79 #include <linux/inet.h>
80 #include <linux/netdevice.h>
81 #include <linux/proc_fs.h>
82 #include <linux/init.h>
83 #include <linux/workqueue.h>
84 #include <linux/skbuff.h>
85 #include <linux/inetdevice.h>
86 #include <linux/igmp.h>
87 #include <linux/pkt_sched.h>
88 #include <linux/mroute.h>
89 #include <linux/netfilter_ipv4.h>
90 #include <linux/random.h>
91 #include <linux/jhash.h>
92 #include <linux/rcupdate.h>
93 #include <linux/times.h>
94 #include <linux/slab.h>
95 #include <linux/prefetch.h>
97 #include <net/net_namespace.h>
98 #include <net/protocol.h>
100 #include <net/route.h>
101 #include <net/inetpeer.h>
102 #include <net/sock.h>
103 #include <net/ip_fib.h>
106 #include <net/icmp.h>
107 #include <net/xfrm.h>
108 #include <net/netevent.h>
109 #include <net/rtnetlink.h>
111 #include <linux/sysctl.h>
112 #include <linux/kmemleak.h>
114 #include <net/secure_seq.h>
116 #define RT_FL_TOS(oldflp4) \
117 ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
119 #define IP_MAX_MTU 0xFFF0
121 #define RT_GC_TIMEOUT (300*HZ)
123 static int ip_rt_max_size;
124 static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
125 static int ip_rt_gc_interval __read_mostly = 60 * HZ;
126 static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
127 static int ip_rt_redirect_number __read_mostly = 9;
128 static int ip_rt_redirect_load __read_mostly = HZ / 50;
129 static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
130 static int ip_rt_error_cost __read_mostly = HZ;
131 static int ip_rt_error_burst __read_mostly = 5 * HZ;
132 static int ip_rt_gc_elasticity __read_mostly = 8;
133 static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
134 static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
135 static int ip_rt_min_advmss __read_mostly = 256;
138 * Interface to generic destination cache.
141 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
142 static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
143 static unsigned int ipv4_mtu(const struct dst_entry *dst);
144 static void ipv4_dst_destroy(struct dst_entry *dst);
145 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
146 static void ipv4_link_failure(struct sk_buff *skb);
147 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
148 struct sk_buff *skb, u32 mtu);
149 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk,
150 struct sk_buff *skb);
152 static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
157 static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
163 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
167 static struct dst_ops ipv4_dst_ops = {
169 .protocol = cpu_to_be16(ETH_P_IP),
170 .check = ipv4_dst_check,
171 .default_advmss = ipv4_default_advmss,
173 .cow_metrics = ipv4_cow_metrics,
174 .destroy = ipv4_dst_destroy,
175 .ifdown = ipv4_dst_ifdown,
176 .negative_advice = ipv4_negative_advice,
177 .link_failure = ipv4_link_failure,
178 .update_pmtu = ip_rt_update_pmtu,
179 .redirect = ip_do_redirect,
180 .local_out = __ip_local_out,
181 .neigh_lookup = ipv4_neigh_lookup,
184 #define ECN_OR_COST(class) TC_PRIO_##class
186 const __u8 ip_tos2prio[16] = {
188 ECN_OR_COST(BESTEFFORT),
190 ECN_OR_COST(BESTEFFORT),
196 ECN_OR_COST(INTERACTIVE),
198 ECN_OR_COST(INTERACTIVE),
199 TC_PRIO_INTERACTIVE_BULK,
200 ECN_OR_COST(INTERACTIVE_BULK),
201 TC_PRIO_INTERACTIVE_BULK,
202 ECN_OR_COST(INTERACTIVE_BULK)
204 EXPORT_SYMBOL(ip_tos2prio);
206 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
207 #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field)
209 static inline int rt_genid(struct net *net)
211 return atomic_read(&net->ipv4.rt_genid);
214 #ifdef CONFIG_PROC_FS
215 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
219 return SEQ_START_TOKEN;
222 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
228 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
232 static int rt_cache_seq_show(struct seq_file *seq, void *v)
234 if (v == SEQ_START_TOKEN)
235 seq_printf(seq, "%-127s\n",
236 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
237 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
242 static const struct seq_operations rt_cache_seq_ops = {
243 .start = rt_cache_seq_start,
244 .next = rt_cache_seq_next,
245 .stop = rt_cache_seq_stop,
246 .show = rt_cache_seq_show,
249 static int rt_cache_seq_open(struct inode *inode, struct file *file)
251 return seq_open(file, &rt_cache_seq_ops);
254 static const struct file_operations rt_cache_seq_fops = {
255 .owner = THIS_MODULE,
256 .open = rt_cache_seq_open,
259 .release = seq_release,
263 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
268 return SEQ_START_TOKEN;
270 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
271 if (!cpu_possible(cpu))
274 return &per_cpu(rt_cache_stat, cpu);
279 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
283 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
284 if (!cpu_possible(cpu))
287 return &per_cpu(rt_cache_stat, cpu);
293 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
298 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
300 struct rt_cache_stat *st = v;
302 if (v == SEQ_START_TOKEN) {
303 seq_printf(seq, "entries in_hit in_slow_tot in_slow_mc in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n");
307 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
308 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
309 dst_entries_get_slow(&ipv4_dst_ops),
332 static const struct seq_operations rt_cpu_seq_ops = {
333 .start = rt_cpu_seq_start,
334 .next = rt_cpu_seq_next,
335 .stop = rt_cpu_seq_stop,
336 .show = rt_cpu_seq_show,
340 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
342 return seq_open(file, &rt_cpu_seq_ops);
345 static const struct file_operations rt_cpu_seq_fops = {
346 .owner = THIS_MODULE,
347 .open = rt_cpu_seq_open,
350 .release = seq_release,
353 #ifdef CONFIG_IP_ROUTE_CLASSID
354 static int rt_acct_proc_show(struct seq_file *m, void *v)
356 struct ip_rt_acct *dst, *src;
359 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
363 for_each_possible_cpu(i) {
364 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
365 for (j = 0; j < 256; j++) {
366 dst[j].o_bytes += src[j].o_bytes;
367 dst[j].o_packets += src[j].o_packets;
368 dst[j].i_bytes += src[j].i_bytes;
369 dst[j].i_packets += src[j].i_packets;
373 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
378 static int rt_acct_proc_open(struct inode *inode, struct file *file)
380 return single_open(file, rt_acct_proc_show, NULL);
383 static const struct file_operations rt_acct_proc_fops = {
384 .owner = THIS_MODULE,
385 .open = rt_acct_proc_open,
388 .release = single_release,
392 static int __net_init ip_rt_do_proc_init(struct net *net)
394 struct proc_dir_entry *pde;
396 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
401 pde = proc_create("rt_cache", S_IRUGO,
402 net->proc_net_stat, &rt_cpu_seq_fops);
406 #ifdef CONFIG_IP_ROUTE_CLASSID
407 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
413 #ifdef CONFIG_IP_ROUTE_CLASSID
415 remove_proc_entry("rt_cache", net->proc_net_stat);
418 remove_proc_entry("rt_cache", net->proc_net);
423 static void __net_exit ip_rt_do_proc_exit(struct net *net)
425 remove_proc_entry("rt_cache", net->proc_net_stat);
426 remove_proc_entry("rt_cache", net->proc_net);
427 #ifdef CONFIG_IP_ROUTE_CLASSID
428 remove_proc_entry("rt_acct", net->proc_net);
432 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
433 .init = ip_rt_do_proc_init,
434 .exit = ip_rt_do_proc_exit,
437 static int __init ip_rt_proc_init(void)
439 return register_pernet_subsys(&ip_rt_proc_ops);
443 static inline int ip_rt_proc_init(void)
447 #endif /* CONFIG_PROC_FS */
449 static inline int rt_is_expired(struct rtable *rth)
451 return rth->rt_genid != rt_genid(dev_net(rth->dst.dev));
455 * Perturbation of rt_genid by a small quantity [1..256]
456 * Using 8 bits of shuffling ensure we can call rt_cache_invalidate()
457 * many times (2^24) without giving recent rt_genid.
458 * Jenkins hash is strong enough that litle changes of rt_genid are OK.
460 static void rt_cache_invalidate(struct net *net)
462 unsigned char shuffle;
464 get_random_bytes(&shuffle, sizeof(shuffle));
465 atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
469 * delay < 0 : invalidate cache (fast : entries will be deleted later)
470 * delay >= 0 : invalidate & flush cache (can be long)
472 void rt_cache_flush(struct net *net, int delay)
474 rt_cache_invalidate(net);
477 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
481 struct net_device *dev = dst->dev;
482 const __be32 *pkey = daddr;
483 const struct rtable *rt;
486 rt = (const struct rtable *) dst;
488 pkey = (const __be32 *) &rt->rt_gateway;
490 pkey = &ip_hdr(skb)->daddr;
492 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
495 return neigh_create(&arp_tbl, pkey, dev);
499 * Peer allocation may fail only in serious out-of-memory conditions. However
500 * we still can generate some output.
501 * Random ID selection looks a bit dangerous because we have no chances to
502 * select ID being unique in a reasonable period of time.
503 * But broken packet identifier may be better than no packet at all.
505 static void ip_select_fb_ident(struct iphdr *iph)
507 static DEFINE_SPINLOCK(ip_fb_id_lock);
508 static u32 ip_fallback_id;
511 spin_lock_bh(&ip_fb_id_lock);
512 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
513 iph->id = htons(salt & 0xFFFF);
514 ip_fallback_id = salt;
515 spin_unlock_bh(&ip_fb_id_lock);
518 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
520 struct net *net = dev_net(dst->dev);
521 struct inet_peer *peer;
523 peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
525 iph->id = htons(inet_getid(peer, more));
530 ip_select_fb_ident(iph);
532 EXPORT_SYMBOL(__ip_select_ident);
534 static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk,
535 const struct iphdr *iph,
537 u8 prot, u32 mark, int flow_flags)
540 const struct inet_sock *inet = inet_sk(sk);
542 oif = sk->sk_bound_dev_if;
544 tos = RT_CONN_FLAGS(sk);
545 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
547 flowi4_init_output(fl4, oif, mark, tos,
548 RT_SCOPE_UNIVERSE, prot,
550 iph->daddr, iph->saddr, 0, 0);
553 static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
554 const struct sock *sk)
556 const struct iphdr *iph = ip_hdr(skb);
557 int oif = skb->dev->ifindex;
558 u8 tos = RT_TOS(iph->tos);
559 u8 prot = iph->protocol;
560 u32 mark = skb->mark;
562 __build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0);
565 static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
567 const struct inet_sock *inet = inet_sk(sk);
568 const struct ip_options_rcu *inet_opt;
569 __be32 daddr = inet->inet_daddr;
572 inet_opt = rcu_dereference(inet->inet_opt);
573 if (inet_opt && inet_opt->opt.srr)
574 daddr = inet_opt->opt.faddr;
575 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
576 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
577 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
578 inet_sk_flowi_flags(sk),
579 daddr, inet->inet_saddr, 0, 0);
583 static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
584 const struct sk_buff *skb)
587 build_skb_flow_key(fl4, skb, sk);
589 build_sk_flow_key(fl4, sk);
592 static DEFINE_SEQLOCK(fnhe_seqlock);
594 static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
596 struct fib_nh_exception *fnhe, *oldest;
598 oldest = rcu_dereference(hash->chain);
599 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
600 fnhe = rcu_dereference(fnhe->fnhe_next)) {
601 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
607 static inline u32 fnhe_hashfun(__be32 daddr)
611 hval = (__force u32) daddr;
612 hval ^= (hval >> 11) ^ (hval >> 22);
614 return hval & (FNHE_HASH_SIZE - 1);
617 static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
618 u32 pmtu, unsigned long expires)
620 struct fnhe_hash_bucket *hash;
621 struct fib_nh_exception *fnhe;
623 u32 hval = fnhe_hashfun(daddr);
625 write_seqlock_bh(&fnhe_seqlock);
627 hash = nh->nh_exceptions;
629 hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC);
632 nh->nh_exceptions = hash;
638 for (fnhe = rcu_dereference(hash->chain); fnhe;
639 fnhe = rcu_dereference(fnhe->fnhe_next)) {
640 if (fnhe->fnhe_daddr == daddr)
649 fnhe->fnhe_pmtu = pmtu;
650 fnhe->fnhe_expires = expires;
653 if (depth > FNHE_RECLAIM_DEPTH)
654 fnhe = fnhe_oldest(hash);
656 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
660 fnhe->fnhe_next = hash->chain;
661 rcu_assign_pointer(hash->chain, fnhe);
663 fnhe->fnhe_daddr = daddr;
665 fnhe->fnhe_pmtu = pmtu;
666 fnhe->fnhe_expires = expires;
669 fnhe->fnhe_stamp = jiffies;
672 write_sequnlock_bh(&fnhe_seqlock);
676 static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4)
678 __be32 new_gw = icmp_hdr(skb)->un.gateway;
679 __be32 old_gw = ip_hdr(skb)->saddr;
680 struct net_device *dev = skb->dev;
681 struct in_device *in_dev;
682 struct fib_result res;
686 switch (icmp_hdr(skb)->code & 7) {
688 case ICMP_REDIR_NETTOS:
689 case ICMP_REDIR_HOST:
690 case ICMP_REDIR_HOSTTOS:
697 if (rt->rt_gateway != old_gw)
700 in_dev = __in_dev_get_rcu(dev);
705 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
706 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
707 ipv4_is_zeronet(new_gw))
708 goto reject_redirect;
710 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
711 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
712 goto reject_redirect;
713 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
714 goto reject_redirect;
716 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
717 goto reject_redirect;
720 n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw);
722 if (!(n->nud_state & NUD_VALID)) {
723 neigh_event_send(n, NULL);
725 if (fib_lookup(net, fl4, &res) == 0) {
726 struct fib_nh *nh = &FIB_RES_NH(res);
728 update_or_create_fnhe(nh, fl4->daddr, new_gw,
731 rt->rt_gateway = new_gw;
732 rt->rt_flags |= RTCF_REDIRECTED;
733 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
740 #ifdef CONFIG_IP_ROUTE_VERBOSE
741 if (IN_DEV_LOG_MARTIANS(in_dev)) {
742 const struct iphdr *iph = (const struct iphdr *) skb->data;
743 __be32 daddr = iph->daddr;
744 __be32 saddr = iph->saddr;
746 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
747 " Advised path = %pI4 -> %pI4\n",
748 &old_gw, dev->name, &new_gw,
755 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
760 rt = (struct rtable *) dst;
762 ip_rt_build_flow_key(&fl4, sk, skb);
763 __ip_do_redirect(rt, skb, &fl4);
766 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
768 struct rtable *rt = (struct rtable *)dst;
769 struct dst_entry *ret = dst;
772 if (dst->obsolete > 0) {
775 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
786 * 1. The first ip_rt_redirect_number redirects are sent
787 * with exponential backoff, then we stop sending them at all,
788 * assuming that the host ignores our redirects.
789 * 2. If we did not see packets requiring redirects
790 * during ip_rt_redirect_silence, we assume that the host
791 * forgot redirected route and start to send redirects again.
793 * This algorithm is much cheaper and more intelligent than dumb load limiting
796 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
797 * and "frag. need" (breaks PMTU discovery) in icmp.c.
800 void ip_rt_send_redirect(struct sk_buff *skb)
802 struct rtable *rt = skb_rtable(skb);
803 struct in_device *in_dev;
804 struct inet_peer *peer;
809 in_dev = __in_dev_get_rcu(rt->dst.dev);
810 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
814 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
817 net = dev_net(rt->dst.dev);
818 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
820 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
824 /* No redirected packets during ip_rt_redirect_silence;
825 * reset the algorithm.
827 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
828 peer->rate_tokens = 0;
830 /* Too many ignored redirects; do not send anything
831 * set dst.rate_last to the last seen redirected packet.
833 if (peer->rate_tokens >= ip_rt_redirect_number) {
834 peer->rate_last = jiffies;
838 /* Check for load limit; set rate_last to the latest sent
841 if (peer->rate_tokens == 0 ||
844 (ip_rt_redirect_load << peer->rate_tokens)))) {
845 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
846 peer->rate_last = jiffies;
848 #ifdef CONFIG_IP_ROUTE_VERBOSE
850 peer->rate_tokens == ip_rt_redirect_number)
851 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
852 &ip_hdr(skb)->saddr, rt->rt_iif,
853 &rt->rt_dst, &rt->rt_gateway);
860 static int ip_error(struct sk_buff *skb)
862 struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
863 struct rtable *rt = skb_rtable(skb);
864 struct inet_peer *peer;
870 net = dev_net(rt->dst.dev);
871 if (!IN_DEV_FORWARD(in_dev)) {
872 switch (rt->dst.error) {
874 IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS);
878 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
884 switch (rt->dst.error) {
889 code = ICMP_HOST_UNREACH;
892 code = ICMP_NET_UNREACH;
893 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
896 code = ICMP_PKT_FILTERED;
900 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
905 peer->rate_tokens += now - peer->rate_last;
906 if (peer->rate_tokens > ip_rt_error_burst)
907 peer->rate_tokens = ip_rt_error_burst;
908 peer->rate_last = now;
909 if (peer->rate_tokens >= ip_rt_error_cost)
910 peer->rate_tokens -= ip_rt_error_cost;
916 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
922 static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
924 struct fib_result res;
926 if (mtu < ip_rt_min_pmtu)
927 mtu = ip_rt_min_pmtu;
929 if (fib_lookup(dev_net(rt->dst.dev), fl4, &res) == 0) {
930 struct fib_nh *nh = &FIB_RES_NH(res);
932 update_or_create_fnhe(nh, fl4->daddr, 0, mtu,
933 jiffies + ip_rt_mtu_expires);
936 dst_set_expires(&rt->dst, ip_rt_mtu_expires);
939 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
940 struct sk_buff *skb, u32 mtu)
942 struct rtable *rt = (struct rtable *) dst;
945 ip_rt_build_flow_key(&fl4, sk, skb);
946 __ip_rt_update_pmtu(rt, &fl4, mtu);
949 void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
950 int oif, u32 mark, u8 protocol, int flow_flags)
952 const struct iphdr *iph = (const struct iphdr *) skb->data;
956 __build_flow_key(&fl4, NULL, iph, oif,
957 RT_TOS(iph->tos), protocol, mark, flow_flags);
958 rt = __ip_route_output_key(net, &fl4);
960 __ip_rt_update_pmtu(rt, &fl4, mtu);
964 EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
966 void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
968 const struct iphdr *iph = (const struct iphdr *) skb->data;
972 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
973 rt = __ip_route_output_key(sock_net(sk), &fl4);
975 __ip_rt_update_pmtu(rt, &fl4, mtu);
979 EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
981 void ipv4_redirect(struct sk_buff *skb, struct net *net,
982 int oif, u32 mark, u8 protocol, int flow_flags)
984 const struct iphdr *iph = (const struct iphdr *) skb->data;
988 __build_flow_key(&fl4, NULL, iph, oif,
989 RT_TOS(iph->tos), protocol, mark, flow_flags);
990 rt = __ip_route_output_key(net, &fl4);
992 __ip_do_redirect(rt, skb, &fl4);
996 EXPORT_SYMBOL_GPL(ipv4_redirect);
998 void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
1000 const struct iphdr *iph = (const struct iphdr *) skb->data;
1004 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
1005 rt = __ip_route_output_key(sock_net(sk), &fl4);
1007 __ip_do_redirect(rt, skb, &fl4);
1011 EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1013 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1015 struct rtable *rt = (struct rtable *) dst;
1017 if (rt_is_expired(rt))
1022 static void ipv4_dst_destroy(struct dst_entry *dst)
1024 struct rtable *rt = (struct rtable *) dst;
1027 fib_info_put(rt->fi);
1033 static void ipv4_link_failure(struct sk_buff *skb)
1037 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1039 rt = skb_rtable(skb);
1041 dst_set_expires(&rt->dst, 0);
1044 static int ip_rt_bug(struct sk_buff *skb)
1046 pr_debug("%s: %pI4 -> %pI4, %s\n",
1047 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1048 skb->dev ? skb->dev->name : "?");
1055 We do not cache source address of outgoing interface,
1056 because it is used only by IP RR, TS and SRR options,
1057 so that it out of fast path.
1059 BTW remember: "addr" is allowed to be not aligned
1063 void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
1067 if (rt_is_output_route(rt))
1068 src = ip_hdr(skb)->saddr;
1070 struct fib_result res;
1076 memset(&fl4, 0, sizeof(fl4));
1077 fl4.daddr = iph->daddr;
1078 fl4.saddr = iph->saddr;
1079 fl4.flowi4_tos = RT_TOS(iph->tos);
1080 fl4.flowi4_oif = rt->dst.dev->ifindex;
1081 fl4.flowi4_iif = skb->dev->ifindex;
1082 fl4.flowi4_mark = skb->mark;
1085 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0)
1086 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
1088 src = inet_select_addr(rt->dst.dev, rt->rt_gateway,
1092 memcpy(addr, &src, 4);
1095 #ifdef CONFIG_IP_ROUTE_CLASSID
1096 static void set_class_tag(struct rtable *rt, u32 tag)
1098 if (!(rt->dst.tclassid & 0xFFFF))
1099 rt->dst.tclassid |= tag & 0xFFFF;
1100 if (!(rt->dst.tclassid & 0xFFFF0000))
1101 rt->dst.tclassid |= tag & 0xFFFF0000;
1105 static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1107 unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
1110 advmss = max_t(unsigned int, dst->dev->mtu - 40,
1112 if (advmss > 65535 - 40)
1113 advmss = 65535 - 40;
1118 static unsigned int ipv4_mtu(const struct dst_entry *dst)
1120 const struct rtable *rt = (const struct rtable *) dst;
1121 unsigned int mtu = rt->rt_pmtu;
1123 if (mtu && time_after_eq(jiffies, rt->dst.expires))
1127 mtu = dst_metric_raw(dst, RTAX_MTU);
1129 if (mtu && rt_is_output_route(rt))
1132 mtu = dst->dev->mtu;
1134 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
1136 if (rt->rt_gateway != rt->rt_dst && mtu > 576)
1140 if (mtu > IP_MAX_MTU)
1146 static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4,
1147 struct fib_info *fi)
1149 if (fi->fib_metrics != (u32 *) dst_default_metrics) {
1151 atomic_inc(&fi->fib_clntref);
1153 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
1156 static void rt_bind_exception(struct rtable *rt, struct fib_nh *nh, __be32 daddr)
1158 struct fnhe_hash_bucket *hash = nh->nh_exceptions;
1159 struct fib_nh_exception *fnhe;
1162 hval = fnhe_hashfun(daddr);
1165 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1166 fnhe = rcu_dereference(fnhe->fnhe_next)) {
1167 __be32 fnhe_daddr, gw;
1168 unsigned long expires;
1172 seq = read_seqbegin(&fnhe_seqlock);
1173 fnhe_daddr = fnhe->fnhe_daddr;
1175 pmtu = fnhe->fnhe_pmtu;
1176 expires = fnhe->fnhe_expires;
1177 if (read_seqretry(&fnhe_seqlock, seq))
1179 if (daddr != fnhe_daddr)
1182 unsigned long diff = expires - jiffies;
1184 if (time_before(jiffies, expires)) {
1186 dst_set_expires(&rt->dst, diff);
1190 rt->rt_gateway = gw;
1191 fnhe->fnhe_stamp = jiffies;
1196 static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4,
1197 const struct fib_result *res,
1198 struct fib_info *fi, u16 type, u32 itag)
1201 struct fib_nh *nh = &FIB_RES_NH(*res);
1203 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
1204 rt->rt_gateway = nh->nh_gw;
1205 if (unlikely(nh->nh_exceptions))
1206 rt_bind_exception(rt, nh, fl4->daddr);
1207 rt_init_metrics(rt, fl4, fi);
1208 #ifdef CONFIG_IP_ROUTE_CLASSID
1209 rt->dst.tclassid = FIB_RES_NH(*res).nh_tclassid;
1213 #ifdef CONFIG_IP_ROUTE_CLASSID
1214 #ifdef CONFIG_IP_MULTIPLE_TABLES
1215 set_class_tag(rt, res->tclassid);
1217 set_class_tag(rt, itag);
1221 static struct rtable *rt_dst_alloc(struct net_device *dev,
1222 bool nopolicy, bool noxfrm)
1224 return dst_alloc(&ipv4_dst_ops, dev, 1, -1,
1225 DST_HOST | DST_NOCACHE |
1226 (nopolicy ? DST_NOPOLICY : 0) |
1227 (noxfrm ? DST_NOXFRM : 0));
1230 /* called in rcu_read_lock() section */
1231 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1232 u8 tos, struct net_device *dev, int our)
1235 struct in_device *in_dev = __in_dev_get_rcu(dev);
1239 /* Primary sanity checks. */
1244 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1245 skb->protocol != htons(ETH_P_IP))
1248 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1249 if (ipv4_is_loopback(saddr))
1252 if (ipv4_is_zeronet(saddr)) {
1253 if (!ipv4_is_local_multicast(daddr))
1256 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1261 rth = rt_dst_alloc(dev_net(dev)->loopback_dev,
1262 IN_DEV_CONF_GET(in_dev, NOPOLICY), false);
1266 #ifdef CONFIG_IP_ROUTE_CLASSID
1267 rth->dst.tclassid = itag;
1269 rth->dst.output = ip_rt_bug;
1271 rth->rt_genid = rt_genid(dev_net(dev));
1272 rth->rt_flags = RTCF_MULTICAST;
1273 rth->rt_type = RTN_MULTICAST;
1274 rth->rt_dst = daddr;
1275 rth->rt_route_iif = dev->ifindex;
1276 rth->rt_iif = dev->ifindex;
1278 rth->rt_mark = skb->mark;
1280 rth->rt_gateway = daddr;
1283 rth->dst.input= ip_local_deliver;
1284 rth->rt_flags |= RTCF_LOCAL;
1287 #ifdef CONFIG_IP_MROUTE
1288 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1289 rth->dst.input = ip_mr_input;
1291 RT_CACHE_STAT_INC(in_slow_mc);
1293 skb_dst_set(skb, &rth->dst);
1305 static void ip_handle_martian_source(struct net_device *dev,
1306 struct in_device *in_dev,
1307 struct sk_buff *skb,
1311 RT_CACHE_STAT_INC(in_martian_src);
1312 #ifdef CONFIG_IP_ROUTE_VERBOSE
1313 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1315 * RFC1812 recommendation, if source is martian,
1316 * the only hint is MAC header.
1318 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
1319 &daddr, &saddr, dev->name);
1320 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1321 print_hex_dump(KERN_WARNING, "ll header: ",
1322 DUMP_PREFIX_OFFSET, 16, 1,
1323 skb_mac_header(skb),
1324 dev->hard_header_len, true);
1330 /* called in rcu_read_lock() section */
1331 static int __mkroute_input(struct sk_buff *skb,
1332 const struct fib_result *res,
1333 struct in_device *in_dev,
1334 __be32 daddr, __be32 saddr, u32 tos,
1335 struct rtable **result)
1339 struct in_device *out_dev;
1340 unsigned int flags = 0;
1343 /* get a working reference to the output device */
1344 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1345 if (out_dev == NULL) {
1346 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
1351 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
1352 in_dev->dev, in_dev, &itag);
1354 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1361 flags |= RTCF_DIRECTSRC;
1363 if (out_dev == in_dev && err &&
1364 (IN_DEV_SHARED_MEDIA(out_dev) ||
1365 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1366 flags |= RTCF_DOREDIRECT;
1368 if (skb->protocol != htons(ETH_P_IP)) {
1369 /* Not IP (i.e. ARP). Do not create route, if it is
1370 * invalid for proxy arp. DNAT routes are always valid.
1372 * Proxy arp feature have been extended to allow, ARP
1373 * replies back to the same interface, to support
1374 * Private VLAN switch technologies. See arp.c.
1376 if (out_dev == in_dev &&
1377 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1383 rth = rt_dst_alloc(out_dev->dev,
1384 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1385 IN_DEV_CONF_GET(out_dev, NOXFRM));
1391 rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
1392 rth->rt_flags = flags;
1393 rth->rt_type = res->type;
1394 rth->rt_dst = daddr;
1395 rth->rt_route_iif = in_dev->dev->ifindex;
1396 rth->rt_iif = in_dev->dev->ifindex;
1398 rth->rt_mark = skb->mark;
1400 rth->rt_gateway = daddr;
1403 rth->dst.input = ip_forward;
1404 rth->dst.output = ip_output;
1406 rt_set_nexthop(rth, NULL, res, res->fi, res->type, itag);
1414 static int ip_mkroute_input(struct sk_buff *skb,
1415 struct fib_result *res,
1416 const struct flowi4 *fl4,
1417 struct in_device *in_dev,
1418 __be32 daddr, __be32 saddr, u32 tos)
1420 struct rtable *rth = NULL;
1423 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1424 if (res->fi && res->fi->fib_nhs > 1)
1425 fib_select_multipath(res);
1428 /* create a routing cache entry */
1429 err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
1433 skb_dst_set(skb, &rth->dst);
1438 * NOTE. We drop all the packets that has local source
1439 * addresses, because every properly looped back packet
1440 * must have correct destination already attached by output routine.
1442 * Such approach solves two big problems:
1443 * 1. Not simplex devices are handled properly.
1444 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1445 * called with rcu_read_lock()
1448 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1449 u8 tos, struct net_device *dev)
1451 struct fib_result res;
1452 struct in_device *in_dev = __in_dev_get_rcu(dev);
1454 unsigned int flags = 0;
1458 struct net *net = dev_net(dev);
1460 /* IP on this device is disabled. */
1465 /* Check for the most weird martians, which can be not detected
1469 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
1470 goto martian_source;
1472 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
1475 /* Accept zero addresses only to limited broadcast;
1476 * I even do not know to fix it or not. Waiting for complains :-)
1478 if (ipv4_is_zeronet(saddr))
1479 goto martian_source;
1481 if (ipv4_is_zeronet(daddr))
1482 goto martian_destination;
1484 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) {
1485 if (ipv4_is_loopback(daddr))
1486 goto martian_destination;
1488 if (ipv4_is_loopback(saddr))
1489 goto martian_source;
1493 * Now we are ready to route packet.
1496 fl4.flowi4_iif = dev->ifindex;
1497 fl4.flowi4_mark = skb->mark;
1498 fl4.flowi4_tos = tos;
1499 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
1502 err = fib_lookup(net, &fl4, &res);
1506 RT_CACHE_STAT_INC(in_slow_tot);
1508 if (res.type == RTN_BROADCAST)
1511 if (res.type == RTN_LOCAL) {
1512 err = fib_validate_source(skb, saddr, daddr, tos,
1513 net->loopback_dev->ifindex,
1514 dev, in_dev, &itag);
1516 goto martian_source_keep_err;
1518 flags |= RTCF_DIRECTSRC;
1522 if (!IN_DEV_FORWARD(in_dev))
1524 if (res.type != RTN_UNICAST)
1525 goto martian_destination;
1527 err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos);
1531 if (skb->protocol != htons(ETH_P_IP))
1534 if (!ipv4_is_zeronet(saddr)) {
1535 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1538 goto martian_source_keep_err;
1540 flags |= RTCF_DIRECTSRC;
1542 flags |= RTCF_BROADCAST;
1543 res.type = RTN_BROADCAST;
1544 RT_CACHE_STAT_INC(in_brd);
1547 rth = rt_dst_alloc(net->loopback_dev,
1548 IN_DEV_CONF_GET(in_dev, NOPOLICY), false);
1552 rth->dst.input= ip_local_deliver;
1553 rth->dst.output= ip_rt_bug;
1554 #ifdef CONFIG_IP_ROUTE_CLASSID
1555 rth->dst.tclassid = itag;
1558 rth->rt_genid = rt_genid(net);
1559 rth->rt_flags = flags|RTCF_LOCAL;
1560 rth->rt_type = res.type;
1561 rth->rt_dst = daddr;
1562 rth->rt_route_iif = dev->ifindex;
1563 rth->rt_iif = dev->ifindex;
1565 rth->rt_mark = skb->mark;
1567 rth->rt_gateway = daddr;
1569 if (res.type == RTN_UNREACHABLE) {
1570 rth->dst.input= ip_error;
1571 rth->dst.error= -err;
1572 rth->rt_flags &= ~RTCF_LOCAL;
1574 skb_dst_set(skb, &rth->dst);
1579 RT_CACHE_STAT_INC(in_no_route);
1580 res.type = RTN_UNREACHABLE;
1586 * Do not cache martian addresses: they should be logged (RFC1812)
1588 martian_destination:
1589 RT_CACHE_STAT_INC(in_martian_dst);
1590 #ifdef CONFIG_IP_ROUTE_VERBOSE
1591 if (IN_DEV_LOG_MARTIANS(in_dev))
1592 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
1593 &daddr, &saddr, dev->name);
1606 martian_source_keep_err:
1607 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
1611 int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1612 u8 tos, struct net_device *dev)
1618 /* Multicast recognition logic is moved from route cache to here.
1619 The problem was that too many Ethernet cards have broken/missing
1620 hardware multicast filters :-( As result the host on multicasting
1621 network acquires a lot of useless route cache entries, sort of
1622 SDR messages from all the world. Now we try to get rid of them.
1623 Really, provided software IP multicast filter is organized
1624 reasonably (at least, hashed), it does not result in a slowdown
1625 comparing with route cache reject entries.
1626 Note, that multicast routers are not affected, because
1627 route cache entry is created eventually.
1629 if (ipv4_is_multicast(daddr)) {
1630 struct in_device *in_dev = __in_dev_get_rcu(dev);
1633 int our = ip_check_mc_rcu(in_dev, daddr, saddr,
1634 ip_hdr(skb)->protocol);
1636 #ifdef CONFIG_IP_MROUTE
1638 (!ipv4_is_local_multicast(daddr) &&
1639 IN_DEV_MFORWARD(in_dev))
1642 int res = ip_route_input_mc(skb, daddr, saddr,
1651 res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
1655 EXPORT_SYMBOL(ip_route_input);
1657 /* called with rcu_read_lock() */
1658 static struct rtable *__mkroute_output(const struct fib_result *res,
1659 const struct flowi4 *fl4, int orig_oif,
1660 struct net_device *dev_out,
1663 struct fib_info *fi = res->fi;
1664 struct in_device *in_dev;
1665 u16 type = res->type;
1668 in_dev = __in_dev_get_rcu(dev_out);
1670 return ERR_PTR(-EINVAL);
1672 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1673 if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
1674 return ERR_PTR(-EINVAL);
1676 if (ipv4_is_lbcast(fl4->daddr))
1677 type = RTN_BROADCAST;
1678 else if (ipv4_is_multicast(fl4->daddr))
1679 type = RTN_MULTICAST;
1680 else if (ipv4_is_zeronet(fl4->daddr))
1681 return ERR_PTR(-EINVAL);
1683 if (dev_out->flags & IFF_LOOPBACK)
1684 flags |= RTCF_LOCAL;
1686 if (type == RTN_BROADCAST) {
1687 flags |= RTCF_BROADCAST | RTCF_LOCAL;
1689 } else if (type == RTN_MULTICAST) {
1690 flags |= RTCF_MULTICAST | RTCF_LOCAL;
1691 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
1693 flags &= ~RTCF_LOCAL;
1694 /* If multicast route do not exist use
1695 * default one, but do not gateway in this case.
1698 if (fi && res->prefixlen < 4)
1702 rth = rt_dst_alloc(dev_out,
1703 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1704 IN_DEV_CONF_GET(in_dev, NOXFRM));
1706 return ERR_PTR(-ENOBUFS);
1708 rth->dst.output = ip_output;
1710 rth->rt_genid = rt_genid(dev_net(dev_out));
1711 rth->rt_flags = flags;
1712 rth->rt_type = type;
1713 rth->rt_dst = fl4->daddr;
1714 rth->rt_route_iif = 0;
1715 rth->rt_iif = orig_oif ? : dev_out->ifindex;
1716 rth->rt_oif = orig_oif;
1717 rth->rt_mark = fl4->flowi4_mark;
1719 rth->rt_gateway = fl4->daddr;
1722 RT_CACHE_STAT_INC(out_slow_tot);
1724 if (flags & RTCF_LOCAL)
1725 rth->dst.input = ip_local_deliver;
1726 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
1727 if (flags & RTCF_LOCAL &&
1728 !(dev_out->flags & IFF_LOOPBACK)) {
1729 rth->dst.output = ip_mc_output;
1730 RT_CACHE_STAT_INC(out_slow_mc);
1732 #ifdef CONFIG_IP_MROUTE
1733 if (type == RTN_MULTICAST) {
1734 if (IN_DEV_MFORWARD(in_dev) &&
1735 !ipv4_is_local_multicast(fl4->daddr)) {
1736 rth->dst.input = ip_mr_input;
1737 rth->dst.output = ip_mc_output;
1743 rt_set_nexthop(rth, fl4, res, fi, type, 0);
1745 if (fl4->flowi4_flags & FLOWI_FLAG_RT_NOCACHE)
1746 rth->dst.flags |= DST_NOCACHE;
1752 * Major route resolver routine.
1755 struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
1757 struct net_device *dev_out = NULL;
1758 __u8 tos = RT_FL_TOS(fl4);
1759 unsigned int flags = 0;
1760 struct fib_result res;
1768 orig_oif = fl4->flowi4_oif;
1770 fl4->flowi4_iif = net->loopback_dev->ifindex;
1771 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
1772 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
1773 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
1777 rth = ERR_PTR(-EINVAL);
1778 if (ipv4_is_multicast(fl4->saddr) ||
1779 ipv4_is_lbcast(fl4->saddr) ||
1780 ipv4_is_zeronet(fl4->saddr))
1783 /* I removed check for oif == dev_out->oif here.
1784 It was wrong for two reasons:
1785 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
1786 is assigned to multiple interfaces.
1787 2. Moreover, we are allowed to send packets with saddr
1788 of another iface. --ANK
1791 if (fl4->flowi4_oif == 0 &&
1792 (ipv4_is_multicast(fl4->daddr) ||
1793 ipv4_is_lbcast(fl4->daddr))) {
1794 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1795 dev_out = __ip_dev_find(net, fl4->saddr, false);
1796 if (dev_out == NULL)
1799 /* Special hack: user can direct multicasts
1800 and limited broadcast via necessary interface
1801 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
1802 This hack is not just for fun, it allows
1803 vic,vat and friends to work.
1804 They bind socket to loopback, set ttl to zero
1805 and expect that it will work.
1806 From the viewpoint of routing cache they are broken,
1807 because we are not allowed to build multicast path
1808 with loopback source addr (look, routing cache
1809 cannot know, that ttl is zero, so that packet
1810 will not leave this host and route is valid).
1811 Luckily, this hack is good workaround.
1814 fl4->flowi4_oif = dev_out->ifindex;
1818 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
1819 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1820 if (!__ip_dev_find(net, fl4->saddr, false))
1826 if (fl4->flowi4_oif) {
1827 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
1828 rth = ERR_PTR(-ENODEV);
1829 if (dev_out == NULL)
1832 /* RACE: Check return value of inet_select_addr instead. */
1833 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
1834 rth = ERR_PTR(-ENETUNREACH);
1837 if (ipv4_is_local_multicast(fl4->daddr) ||
1838 ipv4_is_lbcast(fl4->daddr)) {
1840 fl4->saddr = inet_select_addr(dev_out, 0,
1845 if (ipv4_is_multicast(fl4->daddr))
1846 fl4->saddr = inet_select_addr(dev_out, 0,
1848 else if (!fl4->daddr)
1849 fl4->saddr = inet_select_addr(dev_out, 0,
1855 fl4->daddr = fl4->saddr;
1857 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
1858 dev_out = net->loopback_dev;
1859 fl4->flowi4_oif = net->loopback_dev->ifindex;
1860 res.type = RTN_LOCAL;
1861 flags |= RTCF_LOCAL;
1865 if (fib_lookup(net, fl4, &res)) {
1868 if (fl4->flowi4_oif) {
1869 /* Apparently, routing tables are wrong. Assume,
1870 that the destination is on link.
1873 Because we are allowed to send to iface
1874 even if it has NO routes and NO assigned
1875 addresses. When oif is specified, routing
1876 tables are looked up with only one purpose:
1877 to catch if destination is gatewayed, rather than
1878 direct. Moreover, if MSG_DONTROUTE is set,
1879 we send packet, ignoring both routing tables
1880 and ifaddr state. --ANK
1883 We could make it even if oif is unknown,
1884 likely IPv6, but we do not.
1887 if (fl4->saddr == 0)
1888 fl4->saddr = inet_select_addr(dev_out, 0,
1890 res.type = RTN_UNICAST;
1893 rth = ERR_PTR(-ENETUNREACH);
1897 if (res.type == RTN_LOCAL) {
1899 if (res.fi->fib_prefsrc)
1900 fl4->saddr = res.fi->fib_prefsrc;
1902 fl4->saddr = fl4->daddr;
1904 dev_out = net->loopback_dev;
1905 fl4->flowi4_oif = dev_out->ifindex;
1907 flags |= RTCF_LOCAL;
1911 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1912 if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
1913 fib_select_multipath(&res);
1916 if (!res.prefixlen &&
1917 res.table->tb_num_default > 1 &&
1918 res.type == RTN_UNICAST && !fl4->flowi4_oif)
1919 fib_select_default(&res);
1922 fl4->saddr = FIB_RES_PREFSRC(net, res);
1924 dev_out = FIB_RES_DEV(res);
1925 fl4->flowi4_oif = dev_out->ifindex;
1929 rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags);
1935 EXPORT_SYMBOL_GPL(__ip_route_output_key);
1937 static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
1942 static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
1944 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
1946 return mtu ? : dst->dev->mtu;
1949 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
1950 struct sk_buff *skb, u32 mtu)
1954 static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
1955 struct sk_buff *skb)
1959 static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
1965 static struct dst_ops ipv4_dst_blackhole_ops = {
1967 .protocol = cpu_to_be16(ETH_P_IP),
1968 .destroy = ipv4_dst_destroy,
1969 .check = ipv4_blackhole_dst_check,
1970 .mtu = ipv4_blackhole_mtu,
1971 .default_advmss = ipv4_default_advmss,
1972 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
1973 .redirect = ipv4_rt_blackhole_redirect,
1974 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
1975 .neigh_lookup = ipv4_neigh_lookup,
1978 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1980 struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, 0, 0);
1981 struct rtable *ort = (struct rtable *) dst_orig;
1984 struct dst_entry *new = &rt->dst;
1987 new->input = dst_discard;
1988 new->output = dst_discard;
1990 new->dev = ort->dst.dev;
1994 rt->rt_route_iif = ort->rt_route_iif;
1995 rt->rt_iif = ort->rt_iif;
1996 rt->rt_oif = ort->rt_oif;
1997 rt->rt_mark = ort->rt_mark;
1998 rt->rt_pmtu = ort->rt_pmtu;
2000 rt->rt_genid = rt_genid(net);
2001 rt->rt_flags = ort->rt_flags;
2002 rt->rt_type = ort->rt_type;
2003 rt->rt_dst = ort->rt_dst;
2004 rt->rt_gateway = ort->rt_gateway;
2007 atomic_inc(&rt->fi->fib_clntref);
2012 dst_release(dst_orig);
2014 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2017 struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
2020 struct rtable *rt = __ip_route_output_key(net, flp4);
2025 if (flp4->flowi4_proto)
2026 rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
2027 flowi4_to_flowi(flp4),
2032 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2034 static int rt_fill_info(struct net *net, __be32 src, struct flowi4 *fl4,
2035 struct sk_buff *skb, u32 pid, u32 seq, int event,
2036 int nowait, unsigned int flags)
2038 struct rtable *rt = skb_rtable(skb);
2040 struct nlmsghdr *nlh;
2041 unsigned long expires = 0;
2043 u32 metrics[RTAX_MAX];
2045 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
2049 r = nlmsg_data(nlh);
2050 r->rtm_family = AF_INET;
2051 r->rtm_dst_len = 32;
2053 r->rtm_tos = fl4->flowi4_tos;
2054 r->rtm_table = RT_TABLE_MAIN;
2055 if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN))
2056 goto nla_put_failure;
2057 r->rtm_type = rt->rt_type;
2058 r->rtm_scope = RT_SCOPE_UNIVERSE;
2059 r->rtm_protocol = RTPROT_UNSPEC;
2060 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2061 if (rt->rt_flags & RTCF_NOTIFY)
2062 r->rtm_flags |= RTM_F_NOTIFY;
2064 if (nla_put_be32(skb, RTA_DST, rt->rt_dst))
2065 goto nla_put_failure;
2067 r->rtm_src_len = 32;
2068 if (nla_put_be32(skb, RTA_SRC, src))
2069 goto nla_put_failure;
2072 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2073 goto nla_put_failure;
2074 #ifdef CONFIG_IP_ROUTE_CLASSID
2075 if (rt->dst.tclassid &&
2076 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2077 goto nla_put_failure;
2079 if (!rt_is_input_route(rt) &&
2080 fl4->saddr != src) {
2081 if (nla_put_be32(skb, RTA_PREFSRC, fl4->saddr))
2082 goto nla_put_failure;
2084 if (fl4->daddr != rt->rt_gateway &&
2085 nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway))
2086 goto nla_put_failure;
2088 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
2090 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2091 if (rtnetlink_put_metrics(skb, metrics) < 0)
2092 goto nla_put_failure;
2095 nla_put_be32(skb, RTA_MARK, rt->rt_mark))
2096 goto nla_put_failure;
2098 error = rt->dst.error;
2099 expires = rt->dst.expires;
2101 if (time_before(jiffies, expires))
2107 if (rt_is_input_route(rt)) {
2108 #ifdef CONFIG_IP_MROUTE
2109 __be32 dst = rt->rt_dst;
2111 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2112 IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
2113 int err = ipmr_get_route(net, skb,
2114 fl4->saddr, fl4->daddr,
2120 goto nla_put_failure;
2122 if (err == -EMSGSIZE)
2123 goto nla_put_failure;
2129 if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))
2130 goto nla_put_failure;
2133 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
2134 goto nla_put_failure;
2136 return nlmsg_end(skb, nlh);
2139 nlmsg_cancel(skb, nlh);
2143 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
2145 struct net *net = sock_net(in_skb->sk);
2147 struct nlattr *tb[RTA_MAX+1];
2148 struct rtable *rt = NULL;
2155 struct sk_buff *skb;
2157 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2161 rtm = nlmsg_data(nlh);
2163 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2169 /* Reserve room for dummy headers, this skb can pass
2170 through good chunk of routing engine.
2172 skb_reset_mac_header(skb);
2173 skb_reset_network_header(skb);
2175 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2176 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2177 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2179 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2180 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2181 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2182 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2184 memset(&fl4, 0, sizeof(fl4));
2187 fl4.flowi4_tos = rtm->rtm_tos;
2188 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2189 fl4.flowi4_mark = mark;
2192 struct net_device *dev;
2194 dev = __dev_get_by_index(net, iif);
2200 skb->protocol = htons(ETH_P_IP);
2204 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2207 rt = skb_rtable(skb);
2208 if (err == 0 && rt->dst.error)
2209 err = -rt->dst.error;
2211 rt = ip_route_output_key(net, &fl4);
2221 skb_dst_set(skb, &rt->dst);
2222 if (rtm->rtm_flags & RTM_F_NOTIFY)
2223 rt->rt_flags |= RTCF_NOTIFY;
2225 err = rt_fill_info(net, src, &fl4, skb,
2226 NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
2227 RTM_NEWROUTE, 0, 0);
2231 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2240 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2245 void ip_rt_multicast_event(struct in_device *in_dev)
2247 rt_cache_flush(dev_net(in_dev->dev), 0);
2250 #ifdef CONFIG_SYSCTL
2251 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2252 void __user *buffer,
2253 size_t *lenp, loff_t *ppos)
2260 memcpy(&ctl, __ctl, sizeof(ctl));
2261 ctl.data = &flush_delay;
2262 proc_dointvec(&ctl, write, buffer, lenp, ppos);
2264 net = (struct net *)__ctl->extra1;
2265 rt_cache_flush(net, flush_delay);
2272 static ctl_table ipv4_route_table[] = {
2274 .procname = "gc_thresh",
2275 .data = &ipv4_dst_ops.gc_thresh,
2276 .maxlen = sizeof(int),
2278 .proc_handler = proc_dointvec,
2281 .procname = "max_size",
2282 .data = &ip_rt_max_size,
2283 .maxlen = sizeof(int),
2285 .proc_handler = proc_dointvec,
2288 /* Deprecated. Use gc_min_interval_ms */
2290 .procname = "gc_min_interval",
2291 .data = &ip_rt_gc_min_interval,
2292 .maxlen = sizeof(int),
2294 .proc_handler = proc_dointvec_jiffies,
2297 .procname = "gc_min_interval_ms",
2298 .data = &ip_rt_gc_min_interval,
2299 .maxlen = sizeof(int),
2301 .proc_handler = proc_dointvec_ms_jiffies,
2304 .procname = "gc_timeout",
2305 .data = &ip_rt_gc_timeout,
2306 .maxlen = sizeof(int),
2308 .proc_handler = proc_dointvec_jiffies,
2311 .procname = "gc_interval",
2312 .data = &ip_rt_gc_interval,
2313 .maxlen = sizeof(int),
2315 .proc_handler = proc_dointvec_jiffies,
2318 .procname = "redirect_load",
2319 .data = &ip_rt_redirect_load,
2320 .maxlen = sizeof(int),
2322 .proc_handler = proc_dointvec,
2325 .procname = "redirect_number",
2326 .data = &ip_rt_redirect_number,
2327 .maxlen = sizeof(int),
2329 .proc_handler = proc_dointvec,
2332 .procname = "redirect_silence",
2333 .data = &ip_rt_redirect_silence,
2334 .maxlen = sizeof(int),
2336 .proc_handler = proc_dointvec,
2339 .procname = "error_cost",
2340 .data = &ip_rt_error_cost,
2341 .maxlen = sizeof(int),
2343 .proc_handler = proc_dointvec,
2346 .procname = "error_burst",
2347 .data = &ip_rt_error_burst,
2348 .maxlen = sizeof(int),
2350 .proc_handler = proc_dointvec,
2353 .procname = "gc_elasticity",
2354 .data = &ip_rt_gc_elasticity,
2355 .maxlen = sizeof(int),
2357 .proc_handler = proc_dointvec,
2360 .procname = "mtu_expires",
2361 .data = &ip_rt_mtu_expires,
2362 .maxlen = sizeof(int),
2364 .proc_handler = proc_dointvec_jiffies,
2367 .procname = "min_pmtu",
2368 .data = &ip_rt_min_pmtu,
2369 .maxlen = sizeof(int),
2371 .proc_handler = proc_dointvec,
2374 .procname = "min_adv_mss",
2375 .data = &ip_rt_min_advmss,
2376 .maxlen = sizeof(int),
2378 .proc_handler = proc_dointvec,
2383 static struct ctl_table ipv4_route_flush_table[] = {
2385 .procname = "flush",
2386 .maxlen = sizeof(int),
2388 .proc_handler = ipv4_sysctl_rtcache_flush,
2393 static __net_init int sysctl_route_net_init(struct net *net)
2395 struct ctl_table *tbl;
2397 tbl = ipv4_route_flush_table;
2398 if (!net_eq(net, &init_net)) {
2399 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
2403 tbl[0].extra1 = net;
2405 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
2406 if (net->ipv4.route_hdr == NULL)
2411 if (tbl != ipv4_route_flush_table)
2417 static __net_exit void sysctl_route_net_exit(struct net *net)
2419 struct ctl_table *tbl;
2421 tbl = net->ipv4.route_hdr->ctl_table_arg;
2422 unregister_net_sysctl_table(net->ipv4.route_hdr);
2423 BUG_ON(tbl == ipv4_route_flush_table);
2427 static __net_initdata struct pernet_operations sysctl_route_ops = {
2428 .init = sysctl_route_net_init,
2429 .exit = sysctl_route_net_exit,
2433 static __net_init int rt_genid_init(struct net *net)
2435 get_random_bytes(&net->ipv4.rt_genid,
2436 sizeof(net->ipv4.rt_genid));
2437 get_random_bytes(&net->ipv4.dev_addr_genid,
2438 sizeof(net->ipv4.dev_addr_genid));
2442 static __net_initdata struct pernet_operations rt_genid_ops = {
2443 .init = rt_genid_init,
2446 static int __net_init ipv4_inetpeer_init(struct net *net)
2448 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
2452 inet_peer_base_init(bp);
2453 net->ipv4.peers = bp;
2457 static void __net_exit ipv4_inetpeer_exit(struct net *net)
2459 struct inet_peer_base *bp = net->ipv4.peers;
2461 net->ipv4.peers = NULL;
2462 inetpeer_invalidate_tree(bp);
2466 static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
2467 .init = ipv4_inetpeer_init,
2468 .exit = ipv4_inetpeer_exit,
2471 #ifdef CONFIG_IP_ROUTE_CLASSID
2472 struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
2473 #endif /* CONFIG_IP_ROUTE_CLASSID */
2475 int __init ip_rt_init(void)
2479 #ifdef CONFIG_IP_ROUTE_CLASSID
2480 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
2482 panic("IP: failed to allocate ip_rt_acct\n");
2485 ipv4_dst_ops.kmem_cachep =
2486 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
2487 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
2489 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
2491 if (dst_entries_init(&ipv4_dst_ops) < 0)
2492 panic("IP: failed to allocate ipv4_dst_ops counter\n");
2494 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
2495 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
2497 ipv4_dst_ops.gc_thresh = ~0;
2498 ip_rt_max_size = INT_MAX;
2503 if (ip_rt_proc_init())
2504 pr_err("Unable to create route proc files\n");
2507 xfrm4_init(ip_rt_max_size);
2509 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL);
2511 #ifdef CONFIG_SYSCTL
2512 register_pernet_subsys(&sysctl_route_ops);
2514 register_pernet_subsys(&rt_genid_ops);
2515 register_pernet_subsys(&ipv4_inetpeer_ops);
2519 #ifdef CONFIG_SYSCTL
2521 * We really need to sanitize the damn ipv4 init order, then all
2522 * this nonsense will go away.
2524 void __init ip_static_sysctl_init(void)
2526 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);