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/string.h>
74 #include <linux/socket.h>
75 #include <linux/sockios.h>
76 #include <linux/errno.h>
78 #include <linux/inet.h>
79 #include <linux/netdevice.h>
80 #include <linux/proc_fs.h>
81 #include <linux/init.h>
82 #include <linux/skbuff.h>
83 #include <linux/inetdevice.h>
84 #include <linux/igmp.h>
85 #include <linux/pkt_sched.h>
86 #include <linux/mroute.h>
87 #include <linux/netfilter_ipv4.h>
88 #include <linux/random.h>
89 #include <linux/rcupdate.h>
90 #include <linux/times.h>
91 #include <linux/slab.h>
93 #include <net/net_namespace.h>
94 #include <net/protocol.h>
96 #include <net/route.h>
97 #include <net/inetpeer.h>
99 #include <net/ip_fib.h>
102 #include <net/icmp.h>
103 #include <net/xfrm.h>
104 #include <net/netevent.h>
105 #include <net/rtnetlink.h>
107 #include <linux/sysctl.h>
108 #include <linux/kmemleak.h>
110 #include <net/secure_seq.h>
112 #define RT_FL_TOS(oldflp4) \
113 ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
115 #define IP_MAX_MTU 0xFFF0
117 #define RT_GC_TIMEOUT (300*HZ)
119 static int ip_rt_max_size;
120 static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
121 static int ip_rt_gc_interval __read_mostly = 60 * HZ;
122 static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
123 static int ip_rt_redirect_number __read_mostly = 9;
124 static int ip_rt_redirect_load __read_mostly = HZ / 50;
125 static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
126 static int ip_rt_error_cost __read_mostly = HZ;
127 static int ip_rt_error_burst __read_mostly = 5 * HZ;
128 static int ip_rt_gc_elasticity __read_mostly = 8;
129 static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
130 static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
131 static int ip_rt_min_advmss __read_mostly = 256;
134 * Interface to generic destination cache.
137 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
138 static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
139 static unsigned int ipv4_mtu(const struct dst_entry *dst);
140 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
141 static void ipv4_link_failure(struct sk_buff *skb);
142 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
143 struct sk_buff *skb, u32 mtu);
144 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk,
145 struct sk_buff *skb);
146 static void ipv4_dst_destroy(struct dst_entry *dst);
148 static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
153 static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
159 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
163 static struct dst_ops ipv4_dst_ops = {
165 .protocol = cpu_to_be16(ETH_P_IP),
166 .check = ipv4_dst_check,
167 .default_advmss = ipv4_default_advmss,
169 .cow_metrics = ipv4_cow_metrics,
170 .destroy = ipv4_dst_destroy,
171 .ifdown = ipv4_dst_ifdown,
172 .negative_advice = ipv4_negative_advice,
173 .link_failure = ipv4_link_failure,
174 .update_pmtu = ip_rt_update_pmtu,
175 .redirect = ip_do_redirect,
176 .local_out = __ip_local_out,
177 .neigh_lookup = ipv4_neigh_lookup,
180 #define ECN_OR_COST(class) TC_PRIO_##class
182 const __u8 ip_tos2prio[16] = {
184 ECN_OR_COST(BESTEFFORT),
186 ECN_OR_COST(BESTEFFORT),
192 ECN_OR_COST(INTERACTIVE),
194 ECN_OR_COST(INTERACTIVE),
195 TC_PRIO_INTERACTIVE_BULK,
196 ECN_OR_COST(INTERACTIVE_BULK),
197 TC_PRIO_INTERACTIVE_BULK,
198 ECN_OR_COST(INTERACTIVE_BULK)
200 EXPORT_SYMBOL(ip_tos2prio);
202 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
203 #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field)
205 static inline int rt_genid(struct net *net)
207 return atomic_read(&net->ipv4.rt_genid);
210 #ifdef CONFIG_PROC_FS
211 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
215 return SEQ_START_TOKEN;
218 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
224 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
228 static int rt_cache_seq_show(struct seq_file *seq, void *v)
230 if (v == SEQ_START_TOKEN)
231 seq_printf(seq, "%-127s\n",
232 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
233 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
238 static const struct seq_operations rt_cache_seq_ops = {
239 .start = rt_cache_seq_start,
240 .next = rt_cache_seq_next,
241 .stop = rt_cache_seq_stop,
242 .show = rt_cache_seq_show,
245 static int rt_cache_seq_open(struct inode *inode, struct file *file)
247 return seq_open(file, &rt_cache_seq_ops);
250 static const struct file_operations rt_cache_seq_fops = {
251 .owner = THIS_MODULE,
252 .open = rt_cache_seq_open,
255 .release = seq_release,
259 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
264 return SEQ_START_TOKEN;
266 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
267 if (!cpu_possible(cpu))
270 return &per_cpu(rt_cache_stat, cpu);
275 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
279 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
280 if (!cpu_possible(cpu))
283 return &per_cpu(rt_cache_stat, cpu);
289 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
294 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
296 struct rt_cache_stat *st = v;
298 if (v == SEQ_START_TOKEN) {
299 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");
303 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
304 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
305 dst_entries_get_slow(&ipv4_dst_ops),
328 static const struct seq_operations rt_cpu_seq_ops = {
329 .start = rt_cpu_seq_start,
330 .next = rt_cpu_seq_next,
331 .stop = rt_cpu_seq_stop,
332 .show = rt_cpu_seq_show,
336 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
338 return seq_open(file, &rt_cpu_seq_ops);
341 static const struct file_operations rt_cpu_seq_fops = {
342 .owner = THIS_MODULE,
343 .open = rt_cpu_seq_open,
346 .release = seq_release,
349 #ifdef CONFIG_IP_ROUTE_CLASSID
350 static int rt_acct_proc_show(struct seq_file *m, void *v)
352 struct ip_rt_acct *dst, *src;
355 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
359 for_each_possible_cpu(i) {
360 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
361 for (j = 0; j < 256; j++) {
362 dst[j].o_bytes += src[j].o_bytes;
363 dst[j].o_packets += src[j].o_packets;
364 dst[j].i_bytes += src[j].i_bytes;
365 dst[j].i_packets += src[j].i_packets;
369 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
374 static int rt_acct_proc_open(struct inode *inode, struct file *file)
376 return single_open(file, rt_acct_proc_show, NULL);
379 static const struct file_operations rt_acct_proc_fops = {
380 .owner = THIS_MODULE,
381 .open = rt_acct_proc_open,
384 .release = single_release,
388 static int __net_init ip_rt_do_proc_init(struct net *net)
390 struct proc_dir_entry *pde;
392 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
397 pde = proc_create("rt_cache", S_IRUGO,
398 net->proc_net_stat, &rt_cpu_seq_fops);
402 #ifdef CONFIG_IP_ROUTE_CLASSID
403 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
409 #ifdef CONFIG_IP_ROUTE_CLASSID
411 remove_proc_entry("rt_cache", net->proc_net_stat);
414 remove_proc_entry("rt_cache", net->proc_net);
419 static void __net_exit ip_rt_do_proc_exit(struct net *net)
421 remove_proc_entry("rt_cache", net->proc_net_stat);
422 remove_proc_entry("rt_cache", net->proc_net);
423 #ifdef CONFIG_IP_ROUTE_CLASSID
424 remove_proc_entry("rt_acct", net->proc_net);
428 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
429 .init = ip_rt_do_proc_init,
430 .exit = ip_rt_do_proc_exit,
433 static int __init ip_rt_proc_init(void)
435 return register_pernet_subsys(&ip_rt_proc_ops);
439 static inline int ip_rt_proc_init(void)
443 #endif /* CONFIG_PROC_FS */
445 static inline bool rt_is_expired(const struct rtable *rth)
447 return rth->rt_genid != rt_genid(dev_net(rth->dst.dev));
451 * Perturbation of rt_genid by a small quantity [1..256]
452 * Using 8 bits of shuffling ensure we can call rt_cache_invalidate()
453 * many times (2^24) without giving recent rt_genid.
454 * Jenkins hash is strong enough that litle changes of rt_genid are OK.
456 static void rt_cache_invalidate(struct net *net)
458 unsigned char shuffle;
460 get_random_bytes(&shuffle, sizeof(shuffle));
461 atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
465 * delay < 0 : invalidate cache (fast : entries will be deleted later)
466 * delay >= 0 : invalidate & flush cache (can be long)
468 void rt_cache_flush(struct net *net, int delay)
470 rt_cache_invalidate(net);
473 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
477 struct net_device *dev = dst->dev;
478 const __be32 *pkey = daddr;
479 const struct rtable *rt;
482 rt = (const struct rtable *) dst;
484 pkey = (const __be32 *) &rt->rt_gateway;
486 pkey = &ip_hdr(skb)->daddr;
488 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
491 return neigh_create(&arp_tbl, pkey, dev);
495 * Peer allocation may fail only in serious out-of-memory conditions. However
496 * we still can generate some output.
497 * Random ID selection looks a bit dangerous because we have no chances to
498 * select ID being unique in a reasonable period of time.
499 * But broken packet identifier may be better than no packet at all.
501 static void ip_select_fb_ident(struct iphdr *iph)
503 static DEFINE_SPINLOCK(ip_fb_id_lock);
504 static u32 ip_fallback_id;
507 spin_lock_bh(&ip_fb_id_lock);
508 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
509 iph->id = htons(salt & 0xFFFF);
510 ip_fallback_id = salt;
511 spin_unlock_bh(&ip_fb_id_lock);
514 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
516 struct net *net = dev_net(dst->dev);
517 struct inet_peer *peer;
519 peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
521 iph->id = htons(inet_getid(peer, more));
526 ip_select_fb_ident(iph);
528 EXPORT_SYMBOL(__ip_select_ident);
530 static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk,
531 const struct iphdr *iph,
533 u8 prot, u32 mark, int flow_flags)
536 const struct inet_sock *inet = inet_sk(sk);
538 oif = sk->sk_bound_dev_if;
540 tos = RT_CONN_FLAGS(sk);
541 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
543 flowi4_init_output(fl4, oif, mark, tos,
544 RT_SCOPE_UNIVERSE, prot,
546 iph->daddr, iph->saddr, 0, 0);
549 static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
550 const struct sock *sk)
552 const struct iphdr *iph = ip_hdr(skb);
553 int oif = skb->dev->ifindex;
554 u8 tos = RT_TOS(iph->tos);
555 u8 prot = iph->protocol;
556 u32 mark = skb->mark;
558 __build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0);
561 static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
563 const struct inet_sock *inet = inet_sk(sk);
564 const struct ip_options_rcu *inet_opt;
565 __be32 daddr = inet->inet_daddr;
568 inet_opt = rcu_dereference(inet->inet_opt);
569 if (inet_opt && inet_opt->opt.srr)
570 daddr = inet_opt->opt.faddr;
571 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
572 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
573 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
574 inet_sk_flowi_flags(sk),
575 daddr, inet->inet_saddr, 0, 0);
579 static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
580 const struct sk_buff *skb)
583 build_skb_flow_key(fl4, skb, sk);
585 build_sk_flow_key(fl4, sk);
588 static inline void rt_free(struct rtable *rt)
590 call_rcu(&rt->dst.rcu_head, dst_rcu_free);
593 static DEFINE_SPINLOCK(fnhe_lock);
595 static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
597 struct fib_nh_exception *fnhe, *oldest;
600 oldest = rcu_dereference(hash->chain);
601 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
602 fnhe = rcu_dereference(fnhe->fnhe_next)) {
603 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
606 orig = rcu_dereference(oldest->fnhe_rth);
608 RCU_INIT_POINTER(oldest->fnhe_rth, NULL);
614 static inline u32 fnhe_hashfun(__be32 daddr)
618 hval = (__force u32) daddr;
619 hval ^= (hval >> 11) ^ (hval >> 22);
621 return hval & (FNHE_HASH_SIZE - 1);
624 static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
625 u32 pmtu, unsigned long expires)
627 struct fnhe_hash_bucket *hash;
628 struct fib_nh_exception *fnhe;
630 u32 hval = fnhe_hashfun(daddr);
632 spin_lock_bh(&fnhe_lock);
634 hash = nh->nh_exceptions;
636 hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC);
639 nh->nh_exceptions = hash;
645 for (fnhe = rcu_dereference(hash->chain); fnhe;
646 fnhe = rcu_dereference(fnhe->fnhe_next)) {
647 if (fnhe->fnhe_daddr == daddr)
656 fnhe->fnhe_pmtu = pmtu;
657 fnhe->fnhe_expires = expires;
660 if (depth > FNHE_RECLAIM_DEPTH)
661 fnhe = fnhe_oldest(hash);
663 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
667 fnhe->fnhe_next = hash->chain;
668 rcu_assign_pointer(hash->chain, fnhe);
670 fnhe->fnhe_daddr = daddr;
672 fnhe->fnhe_pmtu = pmtu;
673 fnhe->fnhe_expires = expires;
676 fnhe->fnhe_stamp = jiffies;
679 spin_unlock_bh(&fnhe_lock);
683 static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4,
686 __be32 new_gw = icmp_hdr(skb)->un.gateway;
687 __be32 old_gw = ip_hdr(skb)->saddr;
688 struct net_device *dev = skb->dev;
689 struct in_device *in_dev;
690 struct fib_result res;
694 switch (icmp_hdr(skb)->code & 7) {
696 case ICMP_REDIR_NETTOS:
697 case ICMP_REDIR_HOST:
698 case ICMP_REDIR_HOSTTOS:
705 if (rt->rt_gateway != old_gw)
708 in_dev = __in_dev_get_rcu(dev);
713 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
714 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
715 ipv4_is_zeronet(new_gw))
716 goto reject_redirect;
718 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
719 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
720 goto reject_redirect;
721 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
722 goto reject_redirect;
724 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
725 goto reject_redirect;
728 n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw);
730 if (!(n->nud_state & NUD_VALID)) {
731 neigh_event_send(n, NULL);
733 if (fib_lookup(net, fl4, &res) == 0) {
734 struct fib_nh *nh = &FIB_RES_NH(res);
736 update_or_create_fnhe(nh, fl4->daddr, new_gw,
740 rt->dst.obsolete = DST_OBSOLETE_KILL;
741 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
748 #ifdef CONFIG_IP_ROUTE_VERBOSE
749 if (IN_DEV_LOG_MARTIANS(in_dev)) {
750 const struct iphdr *iph = (const struct iphdr *) skb->data;
751 __be32 daddr = iph->daddr;
752 __be32 saddr = iph->saddr;
754 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
755 " Advised path = %pI4 -> %pI4\n",
756 &old_gw, dev->name, &new_gw,
763 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
768 rt = (struct rtable *) dst;
770 ip_rt_build_flow_key(&fl4, sk, skb);
771 __ip_do_redirect(rt, skb, &fl4, true);
774 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
776 struct rtable *rt = (struct rtable *)dst;
777 struct dst_entry *ret = dst;
780 if (dst->obsolete > 0) {
783 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
794 * 1. The first ip_rt_redirect_number redirects are sent
795 * with exponential backoff, then we stop sending them at all,
796 * assuming that the host ignores our redirects.
797 * 2. If we did not see packets requiring redirects
798 * during ip_rt_redirect_silence, we assume that the host
799 * forgot redirected route and start to send redirects again.
801 * This algorithm is much cheaper and more intelligent than dumb load limiting
804 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
805 * and "frag. need" (breaks PMTU discovery) in icmp.c.
808 void ip_rt_send_redirect(struct sk_buff *skb)
810 struct rtable *rt = skb_rtable(skb);
811 struct in_device *in_dev;
812 struct inet_peer *peer;
817 in_dev = __in_dev_get_rcu(rt->dst.dev);
818 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
822 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
825 net = dev_net(rt->dst.dev);
826 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
828 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
832 /* No redirected packets during ip_rt_redirect_silence;
833 * reset the algorithm.
835 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
836 peer->rate_tokens = 0;
838 /* Too many ignored redirects; do not send anything
839 * set dst.rate_last to the last seen redirected packet.
841 if (peer->rate_tokens >= ip_rt_redirect_number) {
842 peer->rate_last = jiffies;
846 /* Check for load limit; set rate_last to the latest sent
849 if (peer->rate_tokens == 0 ||
852 (ip_rt_redirect_load << peer->rate_tokens)))) {
853 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
854 peer->rate_last = jiffies;
856 #ifdef CONFIG_IP_ROUTE_VERBOSE
858 peer->rate_tokens == ip_rt_redirect_number)
859 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
860 &ip_hdr(skb)->saddr, inet_iif(skb),
861 &ip_hdr(skb)->daddr, &rt->rt_gateway);
868 static int ip_error(struct sk_buff *skb)
870 struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
871 struct rtable *rt = skb_rtable(skb);
872 struct inet_peer *peer;
878 net = dev_net(rt->dst.dev);
879 if (!IN_DEV_FORWARD(in_dev)) {
880 switch (rt->dst.error) {
882 IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS);
886 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
892 switch (rt->dst.error) {
897 code = ICMP_HOST_UNREACH;
900 code = ICMP_NET_UNREACH;
901 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
904 code = ICMP_PKT_FILTERED;
908 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
913 peer->rate_tokens += now - peer->rate_last;
914 if (peer->rate_tokens > ip_rt_error_burst)
915 peer->rate_tokens = ip_rt_error_burst;
916 peer->rate_last = now;
917 if (peer->rate_tokens >= ip_rt_error_cost)
918 peer->rate_tokens -= ip_rt_error_cost;
924 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
930 static u32 __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
932 struct fib_result res;
934 if (mtu < ip_rt_min_pmtu)
935 mtu = ip_rt_min_pmtu;
938 if (fib_lookup(dev_net(rt->dst.dev), fl4, &res) == 0) {
939 struct fib_nh *nh = &FIB_RES_NH(res);
941 update_or_create_fnhe(nh, fl4->daddr, 0, mtu,
942 jiffies + ip_rt_mtu_expires);
948 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
949 struct sk_buff *skb, u32 mtu)
951 struct rtable *rt = (struct rtable *) dst;
954 ip_rt_build_flow_key(&fl4, sk, skb);
955 mtu = __ip_rt_update_pmtu(rt, &fl4, mtu);
958 dst->obsolete = DST_OBSOLETE_KILL;
961 rt->dst.expires = max(1UL, jiffies + ip_rt_mtu_expires);
965 void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
966 int oif, u32 mark, u8 protocol, int flow_flags)
968 const struct iphdr *iph = (const struct iphdr *) skb->data;
972 __build_flow_key(&fl4, NULL, iph, oif,
973 RT_TOS(iph->tos), protocol, mark, flow_flags);
974 rt = __ip_route_output_key(net, &fl4);
976 __ip_rt_update_pmtu(rt, &fl4, mtu);
980 EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
982 void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
984 const struct iphdr *iph = (const struct iphdr *) skb->data;
988 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
989 rt = __ip_route_output_key(sock_net(sk), &fl4);
991 __ip_rt_update_pmtu(rt, &fl4, mtu);
995 EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
997 void ipv4_redirect(struct sk_buff *skb, struct net *net,
998 int oif, u32 mark, u8 protocol, int flow_flags)
1000 const struct iphdr *iph = (const struct iphdr *) skb->data;
1004 __build_flow_key(&fl4, NULL, iph, oif,
1005 RT_TOS(iph->tos), protocol, mark, flow_flags);
1006 rt = __ip_route_output_key(net, &fl4);
1008 __ip_do_redirect(rt, skb, &fl4, false);
1012 EXPORT_SYMBOL_GPL(ipv4_redirect);
1014 void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
1016 const struct iphdr *iph = (const struct iphdr *) skb->data;
1020 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
1021 rt = __ip_route_output_key(sock_net(sk), &fl4);
1023 __ip_do_redirect(rt, skb, &fl4, false);
1027 EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1029 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1031 struct rtable *rt = (struct rtable *) dst;
1033 /* All IPV4 dsts are created with ->obsolete set to the value
1034 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1035 * into this function always.
1037 * When a PMTU/redirect information update invalidates a
1038 * route, this is indicated by setting obsolete to
1039 * DST_OBSOLETE_KILL.
1041 if (dst->obsolete == DST_OBSOLETE_KILL || rt_is_expired(rt))
1046 static void ipv4_link_failure(struct sk_buff *skb)
1050 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1052 rt = skb_rtable(skb);
1054 dst_set_expires(&rt->dst, 0);
1057 static int ip_rt_bug(struct sk_buff *skb)
1059 pr_debug("%s: %pI4 -> %pI4, %s\n",
1060 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1061 skb->dev ? skb->dev->name : "?");
1068 We do not cache source address of outgoing interface,
1069 because it is used only by IP RR, TS and SRR options,
1070 so that it out of fast path.
1072 BTW remember: "addr" is allowed to be not aligned
1076 void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
1080 if (rt_is_output_route(rt))
1081 src = ip_hdr(skb)->saddr;
1083 struct fib_result res;
1089 memset(&fl4, 0, sizeof(fl4));
1090 fl4.daddr = iph->daddr;
1091 fl4.saddr = iph->saddr;
1092 fl4.flowi4_tos = RT_TOS(iph->tos);
1093 fl4.flowi4_oif = rt->dst.dev->ifindex;
1094 fl4.flowi4_iif = skb->dev->ifindex;
1095 fl4.flowi4_mark = skb->mark;
1098 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0)
1099 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
1101 src = inet_select_addr(rt->dst.dev,
1102 rt_nexthop(rt, iph->daddr),
1106 memcpy(addr, &src, 4);
1109 #ifdef CONFIG_IP_ROUTE_CLASSID
1110 static void set_class_tag(struct rtable *rt, u32 tag)
1112 if (!(rt->dst.tclassid & 0xFFFF))
1113 rt->dst.tclassid |= tag & 0xFFFF;
1114 if (!(rt->dst.tclassid & 0xFFFF0000))
1115 rt->dst.tclassid |= tag & 0xFFFF0000;
1119 static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1121 unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
1124 advmss = max_t(unsigned int, dst->dev->mtu - 40,
1126 if (advmss > 65535 - 40)
1127 advmss = 65535 - 40;
1132 static unsigned int ipv4_mtu(const struct dst_entry *dst)
1134 const struct rtable *rt = (const struct rtable *) dst;
1135 unsigned int mtu = rt->rt_pmtu;
1137 if (mtu && time_after_eq(jiffies, rt->dst.expires))
1141 mtu = dst_metric_raw(dst, RTAX_MTU);
1143 if (mtu && rt_is_output_route(rt))
1146 mtu = dst->dev->mtu;
1148 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
1149 if (rt->rt_gateway && mtu > 576)
1153 if (mtu > IP_MAX_MTU)
1159 static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
1161 struct fnhe_hash_bucket *hash = nh->nh_exceptions;
1162 struct fib_nh_exception *fnhe;
1168 hval = fnhe_hashfun(daddr);
1170 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1171 fnhe = rcu_dereference(fnhe->fnhe_next)) {
1172 if (fnhe->fnhe_daddr == daddr)
1178 static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
1183 spin_lock_bh(&fnhe_lock);
1185 if (daddr == fnhe->fnhe_daddr) {
1186 struct rtable *orig;
1188 if (fnhe->fnhe_pmtu) {
1189 unsigned long expires = fnhe->fnhe_expires;
1190 unsigned long diff = expires - jiffies;
1192 if (time_before(jiffies, expires)) {
1193 rt->rt_pmtu = fnhe->fnhe_pmtu;
1194 dst_set_expires(&rt->dst, diff);
1197 if (fnhe->fnhe_gw) {
1198 rt->rt_flags |= RTCF_REDIRECTED;
1199 rt->rt_gateway = fnhe->fnhe_gw;
1202 orig = rcu_dereference(fnhe->fnhe_rth);
1203 rcu_assign_pointer(fnhe->fnhe_rth, rt);
1207 fnhe->fnhe_stamp = jiffies;
1210 /* Routes we intend to cache in nexthop exception have
1211 * the DST_NOCACHE bit clear. However, if we are
1212 * unsuccessful at storing this route into the cache
1213 * we really need to set it.
1215 rt->dst.flags |= DST_NOCACHE;
1217 spin_unlock_bh(&fnhe_lock);
1222 static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt)
1224 struct rtable *orig, *prev, **p;
1227 if (rt_is_input_route(rt)) {
1228 p = (struct rtable **)&nh->nh_rth_input;
1230 if (!nh->nh_pcpu_rth_output)
1232 p = (struct rtable **)__this_cpu_ptr(nh->nh_pcpu_rth_output);
1236 prev = cmpxchg(p, orig, rt);
1241 /* Routes we intend to cache in the FIB nexthop have
1242 * the DST_NOCACHE bit clear. However, if we are
1243 * unsuccessful at storing this route into the cache
1244 * we really need to set it.
1247 rt->dst.flags |= DST_NOCACHE;
1254 static DEFINE_SPINLOCK(rt_uncached_lock);
1255 static LIST_HEAD(rt_uncached_list);
1257 static void rt_add_uncached_list(struct rtable *rt)
1259 spin_lock_bh(&rt_uncached_lock);
1260 list_add_tail(&rt->rt_uncached, &rt_uncached_list);
1261 spin_unlock_bh(&rt_uncached_lock);
1264 static void ipv4_dst_destroy(struct dst_entry *dst)
1266 struct rtable *rt = (struct rtable *) dst;
1268 if (!list_empty(&rt->rt_uncached)) {
1269 spin_lock_bh(&rt_uncached_lock);
1270 list_del(&rt->rt_uncached);
1271 spin_unlock_bh(&rt_uncached_lock);
1275 void rt_flush_dev(struct net_device *dev)
1277 if (!list_empty(&rt_uncached_list)) {
1278 struct net *net = dev_net(dev);
1281 spin_lock_bh(&rt_uncached_lock);
1282 list_for_each_entry(rt, &rt_uncached_list, rt_uncached) {
1283 if (rt->dst.dev != dev)
1285 rt->dst.dev = net->loopback_dev;
1286 dev_hold(rt->dst.dev);
1289 spin_unlock_bh(&rt_uncached_lock);
1293 static bool rt_cache_valid(const struct rtable *rt)
1296 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1300 static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
1301 const struct fib_result *res,
1302 struct fib_nh_exception *fnhe,
1303 struct fib_info *fi, u16 type, u32 itag)
1305 bool cached = false;
1308 struct fib_nh *nh = &FIB_RES_NH(*res);
1310 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
1311 rt->rt_gateway = nh->nh_gw;
1312 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
1313 #ifdef CONFIG_IP_ROUTE_CLASSID
1314 rt->dst.tclassid = nh->nh_tclassid;
1317 cached = rt_bind_exception(rt, fnhe, daddr);
1318 else if (!(rt->dst.flags & DST_NOCACHE))
1319 cached = rt_cache_route(nh, rt);
1321 if (unlikely(!cached))
1322 rt_add_uncached_list(rt);
1324 #ifdef CONFIG_IP_ROUTE_CLASSID
1325 #ifdef CONFIG_IP_MULTIPLE_TABLES
1326 set_class_tag(rt, res->tclassid);
1328 set_class_tag(rt, itag);
1332 static struct rtable *rt_dst_alloc(struct net_device *dev,
1333 bool nopolicy, bool noxfrm, bool will_cache)
1335 return dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
1336 (will_cache ? 0 : (DST_HOST | DST_NOCACHE)) |
1337 (nopolicy ? DST_NOPOLICY : 0) |
1338 (noxfrm ? DST_NOXFRM : 0));
1341 /* called in rcu_read_lock() section */
1342 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1343 u8 tos, struct net_device *dev, int our)
1346 struct in_device *in_dev = __in_dev_get_rcu(dev);
1350 /* Primary sanity checks. */
1355 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1356 skb->protocol != htons(ETH_P_IP))
1359 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1360 if (ipv4_is_loopback(saddr))
1363 if (ipv4_is_zeronet(saddr)) {
1364 if (!ipv4_is_local_multicast(daddr))
1367 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1372 rth = rt_dst_alloc(dev_net(dev)->loopback_dev,
1373 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false);
1377 #ifdef CONFIG_IP_ROUTE_CLASSID
1378 rth->dst.tclassid = itag;
1380 rth->dst.output = ip_rt_bug;
1382 rth->rt_genid = rt_genid(dev_net(dev));
1383 rth->rt_flags = RTCF_MULTICAST;
1384 rth->rt_type = RTN_MULTICAST;
1385 rth->rt_is_input= 1;
1388 rth->rt_gateway = 0;
1389 INIT_LIST_HEAD(&rth->rt_uncached);
1391 rth->dst.input= ip_local_deliver;
1392 rth->rt_flags |= RTCF_LOCAL;
1395 #ifdef CONFIG_IP_MROUTE
1396 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1397 rth->dst.input = ip_mr_input;
1399 RT_CACHE_STAT_INC(in_slow_mc);
1401 skb_dst_set(skb, &rth->dst);
1413 static void ip_handle_martian_source(struct net_device *dev,
1414 struct in_device *in_dev,
1415 struct sk_buff *skb,
1419 RT_CACHE_STAT_INC(in_martian_src);
1420 #ifdef CONFIG_IP_ROUTE_VERBOSE
1421 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1423 * RFC1812 recommendation, if source is martian,
1424 * the only hint is MAC header.
1426 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
1427 &daddr, &saddr, dev->name);
1428 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1429 print_hex_dump(KERN_WARNING, "ll header: ",
1430 DUMP_PREFIX_OFFSET, 16, 1,
1431 skb_mac_header(skb),
1432 dev->hard_header_len, true);
1438 /* called in rcu_read_lock() section */
1439 static int __mkroute_input(struct sk_buff *skb,
1440 const struct fib_result *res,
1441 struct in_device *in_dev,
1442 __be32 daddr, __be32 saddr, u32 tos)
1446 struct in_device *out_dev;
1447 unsigned int flags = 0;
1451 /* get a working reference to the output device */
1452 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1453 if (out_dev == NULL) {
1454 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
1459 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
1460 in_dev->dev, in_dev, &itag);
1462 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1468 if (out_dev == in_dev && err &&
1469 (IN_DEV_SHARED_MEDIA(out_dev) ||
1470 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1471 flags |= RTCF_DOREDIRECT;
1473 if (skb->protocol != htons(ETH_P_IP)) {
1474 /* Not IP (i.e. ARP). Do not create route, if it is
1475 * invalid for proxy arp. DNAT routes are always valid.
1477 * Proxy arp feature have been extended to allow, ARP
1478 * replies back to the same interface, to support
1479 * Private VLAN switch technologies. See arp.c.
1481 if (out_dev == in_dev &&
1482 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1491 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1492 if (rt_cache_valid(rth)) {
1493 skb_dst_set_noref(skb, &rth->dst);
1500 rth = rt_dst_alloc(out_dev->dev,
1501 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1502 IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache);
1508 rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
1509 rth->rt_flags = flags;
1510 rth->rt_type = res->type;
1511 rth->rt_is_input = 1;
1514 rth->rt_gateway = 0;
1515 INIT_LIST_HEAD(&rth->rt_uncached);
1517 rth->dst.input = ip_forward;
1518 rth->dst.output = ip_output;
1520 rt_set_nexthop(rth, daddr, res, NULL, res->fi, res->type, itag);
1521 skb_dst_set(skb, &rth->dst);
1528 static int ip_mkroute_input(struct sk_buff *skb,
1529 struct fib_result *res,
1530 const struct flowi4 *fl4,
1531 struct in_device *in_dev,
1532 __be32 daddr, __be32 saddr, u32 tos)
1534 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1535 if (res->fi && res->fi->fib_nhs > 1)
1536 fib_select_multipath(res);
1539 /* create a routing cache entry */
1540 return __mkroute_input(skb, res, in_dev, daddr, saddr, tos);
1544 * NOTE. We drop all the packets that has local source
1545 * addresses, because every properly looped back packet
1546 * must have correct destination already attached by output routine.
1548 * Such approach solves two big problems:
1549 * 1. Not simplex devices are handled properly.
1550 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1551 * called with rcu_read_lock()
1554 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1555 u8 tos, struct net_device *dev)
1557 struct fib_result res;
1558 struct in_device *in_dev = __in_dev_get_rcu(dev);
1560 unsigned int flags = 0;
1564 struct net *net = dev_net(dev);
1567 /* IP on this device is disabled. */
1572 /* Check for the most weird martians, which can be not detected
1576 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
1577 goto martian_source;
1580 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
1583 /* Accept zero addresses only to limited broadcast;
1584 * I even do not know to fix it or not. Waiting for complains :-)
1586 if (ipv4_is_zeronet(saddr))
1587 goto martian_source;
1589 if (ipv4_is_zeronet(daddr))
1590 goto martian_destination;
1592 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) {
1593 if (ipv4_is_loopback(daddr))
1594 goto martian_destination;
1596 if (ipv4_is_loopback(saddr))
1597 goto martian_source;
1601 * Now we are ready to route packet.
1604 fl4.flowi4_iif = dev->ifindex;
1605 fl4.flowi4_mark = skb->mark;
1606 fl4.flowi4_tos = tos;
1607 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
1610 err = fib_lookup(net, &fl4, &res);
1614 RT_CACHE_STAT_INC(in_slow_tot);
1616 if (res.type == RTN_BROADCAST)
1619 if (res.type == RTN_LOCAL) {
1620 err = fib_validate_source(skb, saddr, daddr, tos,
1621 net->loopback_dev->ifindex,
1622 dev, in_dev, &itag);
1624 goto martian_source_keep_err;
1628 if (!IN_DEV_FORWARD(in_dev))
1630 if (res.type != RTN_UNICAST)
1631 goto martian_destination;
1633 err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos);
1637 if (skb->protocol != htons(ETH_P_IP))
1640 if (!ipv4_is_zeronet(saddr)) {
1641 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1644 goto martian_source_keep_err;
1646 flags |= RTCF_BROADCAST;
1647 res.type = RTN_BROADCAST;
1648 RT_CACHE_STAT_INC(in_brd);
1654 rth = rcu_dereference(FIB_RES_NH(res).nh_rth_input);
1655 if (rt_cache_valid(rth)) {
1656 skb_dst_set_noref(skb, &rth->dst);
1664 rth = rt_dst_alloc(net->loopback_dev,
1665 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache);
1669 rth->dst.input= ip_local_deliver;
1670 rth->dst.output= ip_rt_bug;
1671 #ifdef CONFIG_IP_ROUTE_CLASSID
1672 rth->dst.tclassid = itag;
1675 rth->rt_genid = rt_genid(net);
1676 rth->rt_flags = flags|RTCF_LOCAL;
1677 rth->rt_type = res.type;
1678 rth->rt_is_input = 1;
1681 rth->rt_gateway = 0;
1682 INIT_LIST_HEAD(&rth->rt_uncached);
1683 if (res.type == RTN_UNREACHABLE) {
1684 rth->dst.input= ip_error;
1685 rth->dst.error= -err;
1686 rth->rt_flags &= ~RTCF_LOCAL;
1689 rt_cache_route(&FIB_RES_NH(res), rth);
1690 skb_dst_set(skb, &rth->dst);
1695 RT_CACHE_STAT_INC(in_no_route);
1696 res.type = RTN_UNREACHABLE;
1702 * Do not cache martian addresses: they should be logged (RFC1812)
1704 martian_destination:
1705 RT_CACHE_STAT_INC(in_martian_dst);
1706 #ifdef CONFIG_IP_ROUTE_VERBOSE
1707 if (IN_DEV_LOG_MARTIANS(in_dev))
1708 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
1709 &daddr, &saddr, dev->name);
1722 martian_source_keep_err:
1723 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
1727 int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1728 u8 tos, struct net_device *dev)
1734 /* Multicast recognition logic is moved from route cache to here.
1735 The problem was that too many Ethernet cards have broken/missing
1736 hardware multicast filters :-( As result the host on multicasting
1737 network acquires a lot of useless route cache entries, sort of
1738 SDR messages from all the world. Now we try to get rid of them.
1739 Really, provided software IP multicast filter is organized
1740 reasonably (at least, hashed), it does not result in a slowdown
1741 comparing with route cache reject entries.
1742 Note, that multicast routers are not affected, because
1743 route cache entry is created eventually.
1745 if (ipv4_is_multicast(daddr)) {
1746 struct in_device *in_dev = __in_dev_get_rcu(dev);
1749 int our = ip_check_mc_rcu(in_dev, daddr, saddr,
1750 ip_hdr(skb)->protocol);
1752 #ifdef CONFIG_IP_MROUTE
1754 (!ipv4_is_local_multicast(daddr) &&
1755 IN_DEV_MFORWARD(in_dev))
1758 int res = ip_route_input_mc(skb, daddr, saddr,
1767 res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
1771 EXPORT_SYMBOL(ip_route_input_noref);
1773 /* called with rcu_read_lock() */
1774 static struct rtable *__mkroute_output(const struct fib_result *res,
1775 const struct flowi4 *fl4, int orig_oif,
1776 struct net_device *dev_out,
1779 struct fib_info *fi = res->fi;
1780 struct fib_nh_exception *fnhe;
1781 struct in_device *in_dev;
1782 u16 type = res->type;
1785 in_dev = __in_dev_get_rcu(dev_out);
1787 return ERR_PTR(-EINVAL);
1789 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1790 if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
1791 return ERR_PTR(-EINVAL);
1793 if (ipv4_is_lbcast(fl4->daddr))
1794 type = RTN_BROADCAST;
1795 else if (ipv4_is_multicast(fl4->daddr))
1796 type = RTN_MULTICAST;
1797 else if (ipv4_is_zeronet(fl4->daddr))
1798 return ERR_PTR(-EINVAL);
1800 if (dev_out->flags & IFF_LOOPBACK)
1801 flags |= RTCF_LOCAL;
1803 if (type == RTN_BROADCAST) {
1804 flags |= RTCF_BROADCAST | RTCF_LOCAL;
1806 } else if (type == RTN_MULTICAST) {
1807 flags |= RTCF_MULTICAST | RTCF_LOCAL;
1808 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
1810 flags &= ~RTCF_LOCAL;
1811 /* If multicast route do not exist use
1812 * default one, but do not gateway in this case.
1815 if (fi && res->prefixlen < 4)
1821 struct rtable __rcu **prth;
1823 fnhe = find_exception(&FIB_RES_NH(*res), fl4->daddr);
1825 prth = &fnhe->fnhe_rth;
1827 prth = __this_cpu_ptr(FIB_RES_NH(*res).nh_pcpu_rth_output);
1828 rth = rcu_dereference(*prth);
1829 if (rt_cache_valid(rth)) {
1830 dst_hold(&rth->dst);
1834 rth = rt_dst_alloc(dev_out,
1835 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1836 IN_DEV_CONF_GET(in_dev, NOXFRM),
1839 return ERR_PTR(-ENOBUFS);
1841 rth->dst.output = ip_output;
1843 rth->rt_genid = rt_genid(dev_net(dev_out));
1844 rth->rt_flags = flags;
1845 rth->rt_type = type;
1846 rth->rt_is_input = 0;
1847 rth->rt_iif = orig_oif ? : 0;
1849 rth->rt_gateway = 0;
1850 INIT_LIST_HEAD(&rth->rt_uncached);
1852 RT_CACHE_STAT_INC(out_slow_tot);
1854 if (flags & RTCF_LOCAL)
1855 rth->dst.input = ip_local_deliver;
1856 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
1857 if (flags & RTCF_LOCAL &&
1858 !(dev_out->flags & IFF_LOOPBACK)) {
1859 rth->dst.output = ip_mc_output;
1860 RT_CACHE_STAT_INC(out_slow_mc);
1862 #ifdef CONFIG_IP_MROUTE
1863 if (type == RTN_MULTICAST) {
1864 if (IN_DEV_MFORWARD(in_dev) &&
1865 !ipv4_is_local_multicast(fl4->daddr)) {
1866 rth->dst.input = ip_mr_input;
1867 rth->dst.output = ip_mc_output;
1873 rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0);
1879 * Major route resolver routine.
1882 struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
1884 struct net_device *dev_out = NULL;
1885 __u8 tos = RT_FL_TOS(fl4);
1886 unsigned int flags = 0;
1887 struct fib_result res;
1895 orig_oif = fl4->flowi4_oif;
1897 fl4->flowi4_iif = net->loopback_dev->ifindex;
1898 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
1899 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
1900 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
1904 rth = ERR_PTR(-EINVAL);
1905 if (ipv4_is_multicast(fl4->saddr) ||
1906 ipv4_is_lbcast(fl4->saddr) ||
1907 ipv4_is_zeronet(fl4->saddr))
1910 /* I removed check for oif == dev_out->oif here.
1911 It was wrong for two reasons:
1912 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
1913 is assigned to multiple interfaces.
1914 2. Moreover, we are allowed to send packets with saddr
1915 of another iface. --ANK
1918 if (fl4->flowi4_oif == 0 &&
1919 (ipv4_is_multicast(fl4->daddr) ||
1920 ipv4_is_lbcast(fl4->daddr))) {
1921 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1922 dev_out = __ip_dev_find(net, fl4->saddr, false);
1923 if (dev_out == NULL)
1926 /* Special hack: user can direct multicasts
1927 and limited broadcast via necessary interface
1928 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
1929 This hack is not just for fun, it allows
1930 vic,vat and friends to work.
1931 They bind socket to loopback, set ttl to zero
1932 and expect that it will work.
1933 From the viewpoint of routing cache they are broken,
1934 because we are not allowed to build multicast path
1935 with loopback source addr (look, routing cache
1936 cannot know, that ttl is zero, so that packet
1937 will not leave this host and route is valid).
1938 Luckily, this hack is good workaround.
1941 fl4->flowi4_oif = dev_out->ifindex;
1945 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
1946 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1947 if (!__ip_dev_find(net, fl4->saddr, false))
1953 if (fl4->flowi4_oif) {
1954 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
1955 rth = ERR_PTR(-ENODEV);
1956 if (dev_out == NULL)
1959 /* RACE: Check return value of inet_select_addr instead. */
1960 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
1961 rth = ERR_PTR(-ENETUNREACH);
1964 if (ipv4_is_local_multicast(fl4->daddr) ||
1965 ipv4_is_lbcast(fl4->daddr)) {
1967 fl4->saddr = inet_select_addr(dev_out, 0,
1972 if (ipv4_is_multicast(fl4->daddr))
1973 fl4->saddr = inet_select_addr(dev_out, 0,
1975 else if (!fl4->daddr)
1976 fl4->saddr = inet_select_addr(dev_out, 0,
1982 fl4->daddr = fl4->saddr;
1984 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
1985 dev_out = net->loopback_dev;
1986 fl4->flowi4_oif = net->loopback_dev->ifindex;
1987 res.type = RTN_LOCAL;
1988 flags |= RTCF_LOCAL;
1992 if (fib_lookup(net, fl4, &res)) {
1995 if (fl4->flowi4_oif) {
1996 /* Apparently, routing tables are wrong. Assume,
1997 that the destination is on link.
2000 Because we are allowed to send to iface
2001 even if it has NO routes and NO assigned
2002 addresses. When oif is specified, routing
2003 tables are looked up with only one purpose:
2004 to catch if destination is gatewayed, rather than
2005 direct. Moreover, if MSG_DONTROUTE is set,
2006 we send packet, ignoring both routing tables
2007 and ifaddr state. --ANK
2010 We could make it even if oif is unknown,
2011 likely IPv6, but we do not.
2014 if (fl4->saddr == 0)
2015 fl4->saddr = inet_select_addr(dev_out, 0,
2017 res.type = RTN_UNICAST;
2020 rth = ERR_PTR(-ENETUNREACH);
2024 if (res.type == RTN_LOCAL) {
2026 if (res.fi->fib_prefsrc)
2027 fl4->saddr = res.fi->fib_prefsrc;
2029 fl4->saddr = fl4->daddr;
2031 dev_out = net->loopback_dev;
2032 fl4->flowi4_oif = dev_out->ifindex;
2033 flags |= RTCF_LOCAL;
2037 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2038 if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
2039 fib_select_multipath(&res);
2042 if (!res.prefixlen &&
2043 res.table->tb_num_default > 1 &&
2044 res.type == RTN_UNICAST && !fl4->flowi4_oif)
2045 fib_select_default(&res);
2048 fl4->saddr = FIB_RES_PREFSRC(net, res);
2050 dev_out = FIB_RES_DEV(res);
2051 fl4->flowi4_oif = dev_out->ifindex;
2055 rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags);
2061 EXPORT_SYMBOL_GPL(__ip_route_output_key);
2063 static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2068 static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
2070 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2072 return mtu ? : dst->dev->mtu;
2075 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
2076 struct sk_buff *skb, u32 mtu)
2080 static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
2081 struct sk_buff *skb)
2085 static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
2091 static struct dst_ops ipv4_dst_blackhole_ops = {
2093 .protocol = cpu_to_be16(ETH_P_IP),
2094 .check = ipv4_blackhole_dst_check,
2095 .mtu = ipv4_blackhole_mtu,
2096 .default_advmss = ipv4_default_advmss,
2097 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2098 .redirect = ipv4_rt_blackhole_redirect,
2099 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
2100 .neigh_lookup = ipv4_neigh_lookup,
2103 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2105 struct rtable *ort = (struct rtable *) dst_orig;
2108 rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2110 struct dst_entry *new = &rt->dst;
2113 new->input = dst_discard;
2114 new->output = dst_discard;
2116 new->dev = ort->dst.dev;
2120 rt->rt_is_input = ort->rt_is_input;
2121 rt->rt_iif = ort->rt_iif;
2122 rt->rt_pmtu = ort->rt_pmtu;
2124 rt->rt_genid = rt_genid(net);
2125 rt->rt_flags = ort->rt_flags;
2126 rt->rt_type = ort->rt_type;
2127 rt->rt_gateway = ort->rt_gateway;
2129 INIT_LIST_HEAD(&rt->rt_uncached);
2134 dst_release(dst_orig);
2136 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2139 struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
2142 struct rtable *rt = __ip_route_output_key(net, flp4);
2147 if (flp4->flowi4_proto)
2148 rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
2149 flowi4_to_flowi(flp4),
2154 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2156 static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
2157 struct flowi4 *fl4, struct sk_buff *skb, u32 pid,
2158 u32 seq, int event, int nowait, unsigned int flags)
2160 struct rtable *rt = skb_rtable(skb);
2162 struct nlmsghdr *nlh;
2163 unsigned long expires = 0;
2165 u32 metrics[RTAX_MAX];
2167 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
2171 r = nlmsg_data(nlh);
2172 r->rtm_family = AF_INET;
2173 r->rtm_dst_len = 32;
2175 r->rtm_tos = fl4->flowi4_tos;
2176 r->rtm_table = RT_TABLE_MAIN;
2177 if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN))
2178 goto nla_put_failure;
2179 r->rtm_type = rt->rt_type;
2180 r->rtm_scope = RT_SCOPE_UNIVERSE;
2181 r->rtm_protocol = RTPROT_UNSPEC;
2182 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2183 if (rt->rt_flags & RTCF_NOTIFY)
2184 r->rtm_flags |= RTM_F_NOTIFY;
2186 if (nla_put_be32(skb, RTA_DST, dst))
2187 goto nla_put_failure;
2189 r->rtm_src_len = 32;
2190 if (nla_put_be32(skb, RTA_SRC, src))
2191 goto nla_put_failure;
2194 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2195 goto nla_put_failure;
2196 #ifdef CONFIG_IP_ROUTE_CLASSID
2197 if (rt->dst.tclassid &&
2198 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2199 goto nla_put_failure;
2201 if (!rt_is_input_route(rt) &&
2202 fl4->saddr != src) {
2203 if (nla_put_be32(skb, RTA_PREFSRC, fl4->saddr))
2204 goto nla_put_failure;
2206 if (rt->rt_gateway &&
2207 nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway))
2208 goto nla_put_failure;
2210 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
2212 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2213 if (rtnetlink_put_metrics(skb, metrics) < 0)
2214 goto nla_put_failure;
2216 if (fl4->flowi4_mark &&
2217 nla_put_be32(skb, RTA_MARK, fl4->flowi4_mark))
2218 goto nla_put_failure;
2220 error = rt->dst.error;
2221 expires = rt->dst.expires;
2223 if (time_before(jiffies, expires))
2229 if (rt_is_input_route(rt)) {
2230 if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))
2231 goto nla_put_failure;
2234 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
2235 goto nla_put_failure;
2237 return nlmsg_end(skb, nlh);
2240 nlmsg_cancel(skb, nlh);
2244 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
2246 struct net *net = sock_net(in_skb->sk);
2248 struct nlattr *tb[RTA_MAX+1];
2249 struct rtable *rt = NULL;
2256 struct sk_buff *skb;
2258 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2262 rtm = nlmsg_data(nlh);
2264 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2270 /* Reserve room for dummy headers, this skb can pass
2271 through good chunk of routing engine.
2273 skb_reset_mac_header(skb);
2274 skb_reset_network_header(skb);
2276 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2277 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2278 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2280 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2281 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2282 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2283 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2285 memset(&fl4, 0, sizeof(fl4));
2288 fl4.flowi4_tos = rtm->rtm_tos;
2289 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2290 fl4.flowi4_mark = mark;
2293 struct net_device *dev;
2295 dev = __dev_get_by_index(net, iif);
2301 skb->protocol = htons(ETH_P_IP);
2305 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2308 rt = skb_rtable(skb);
2309 if (err == 0 && rt->dst.error)
2310 err = -rt->dst.error;
2312 rt = ip_route_output_key(net, &fl4);
2322 skb_dst_set(skb, &rt->dst);
2323 if (rtm->rtm_flags & RTM_F_NOTIFY)
2324 rt->rt_flags |= RTCF_NOTIFY;
2326 err = rt_fill_info(net, dst, src, &fl4, skb,
2327 NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
2328 RTM_NEWROUTE, 0, 0);
2332 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2341 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2346 void ip_rt_multicast_event(struct in_device *in_dev)
2348 rt_cache_flush(dev_net(in_dev->dev), 0);
2351 #ifdef CONFIG_SYSCTL
2352 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2353 void __user *buffer,
2354 size_t *lenp, loff_t *ppos)
2361 memcpy(&ctl, __ctl, sizeof(ctl));
2362 ctl.data = &flush_delay;
2363 proc_dointvec(&ctl, write, buffer, lenp, ppos);
2365 net = (struct net *)__ctl->extra1;
2366 rt_cache_flush(net, flush_delay);
2373 static ctl_table ipv4_route_table[] = {
2375 .procname = "gc_thresh",
2376 .data = &ipv4_dst_ops.gc_thresh,
2377 .maxlen = sizeof(int),
2379 .proc_handler = proc_dointvec,
2382 .procname = "max_size",
2383 .data = &ip_rt_max_size,
2384 .maxlen = sizeof(int),
2386 .proc_handler = proc_dointvec,
2389 /* Deprecated. Use gc_min_interval_ms */
2391 .procname = "gc_min_interval",
2392 .data = &ip_rt_gc_min_interval,
2393 .maxlen = sizeof(int),
2395 .proc_handler = proc_dointvec_jiffies,
2398 .procname = "gc_min_interval_ms",
2399 .data = &ip_rt_gc_min_interval,
2400 .maxlen = sizeof(int),
2402 .proc_handler = proc_dointvec_ms_jiffies,
2405 .procname = "gc_timeout",
2406 .data = &ip_rt_gc_timeout,
2407 .maxlen = sizeof(int),
2409 .proc_handler = proc_dointvec_jiffies,
2412 .procname = "gc_interval",
2413 .data = &ip_rt_gc_interval,
2414 .maxlen = sizeof(int),
2416 .proc_handler = proc_dointvec_jiffies,
2419 .procname = "redirect_load",
2420 .data = &ip_rt_redirect_load,
2421 .maxlen = sizeof(int),
2423 .proc_handler = proc_dointvec,
2426 .procname = "redirect_number",
2427 .data = &ip_rt_redirect_number,
2428 .maxlen = sizeof(int),
2430 .proc_handler = proc_dointvec,
2433 .procname = "redirect_silence",
2434 .data = &ip_rt_redirect_silence,
2435 .maxlen = sizeof(int),
2437 .proc_handler = proc_dointvec,
2440 .procname = "error_cost",
2441 .data = &ip_rt_error_cost,
2442 .maxlen = sizeof(int),
2444 .proc_handler = proc_dointvec,
2447 .procname = "error_burst",
2448 .data = &ip_rt_error_burst,
2449 .maxlen = sizeof(int),
2451 .proc_handler = proc_dointvec,
2454 .procname = "gc_elasticity",
2455 .data = &ip_rt_gc_elasticity,
2456 .maxlen = sizeof(int),
2458 .proc_handler = proc_dointvec,
2461 .procname = "mtu_expires",
2462 .data = &ip_rt_mtu_expires,
2463 .maxlen = sizeof(int),
2465 .proc_handler = proc_dointvec_jiffies,
2468 .procname = "min_pmtu",
2469 .data = &ip_rt_min_pmtu,
2470 .maxlen = sizeof(int),
2472 .proc_handler = proc_dointvec,
2475 .procname = "min_adv_mss",
2476 .data = &ip_rt_min_advmss,
2477 .maxlen = sizeof(int),
2479 .proc_handler = proc_dointvec,
2484 static struct ctl_table ipv4_route_flush_table[] = {
2486 .procname = "flush",
2487 .maxlen = sizeof(int),
2489 .proc_handler = ipv4_sysctl_rtcache_flush,
2494 static __net_init int sysctl_route_net_init(struct net *net)
2496 struct ctl_table *tbl;
2498 tbl = ipv4_route_flush_table;
2499 if (!net_eq(net, &init_net)) {
2500 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
2504 tbl[0].extra1 = net;
2506 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
2507 if (net->ipv4.route_hdr == NULL)
2512 if (tbl != ipv4_route_flush_table)
2518 static __net_exit void sysctl_route_net_exit(struct net *net)
2520 struct ctl_table *tbl;
2522 tbl = net->ipv4.route_hdr->ctl_table_arg;
2523 unregister_net_sysctl_table(net->ipv4.route_hdr);
2524 BUG_ON(tbl == ipv4_route_flush_table);
2528 static __net_initdata struct pernet_operations sysctl_route_ops = {
2529 .init = sysctl_route_net_init,
2530 .exit = sysctl_route_net_exit,
2534 static __net_init int rt_genid_init(struct net *net)
2536 get_random_bytes(&net->ipv4.rt_genid,
2537 sizeof(net->ipv4.rt_genid));
2538 get_random_bytes(&net->ipv4.dev_addr_genid,
2539 sizeof(net->ipv4.dev_addr_genid));
2543 static __net_initdata struct pernet_operations rt_genid_ops = {
2544 .init = rt_genid_init,
2547 static int __net_init ipv4_inetpeer_init(struct net *net)
2549 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
2553 inet_peer_base_init(bp);
2554 net->ipv4.peers = bp;
2558 static void __net_exit ipv4_inetpeer_exit(struct net *net)
2560 struct inet_peer_base *bp = net->ipv4.peers;
2562 net->ipv4.peers = NULL;
2563 inetpeer_invalidate_tree(bp);
2567 static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
2568 .init = ipv4_inetpeer_init,
2569 .exit = ipv4_inetpeer_exit,
2572 #ifdef CONFIG_IP_ROUTE_CLASSID
2573 struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
2574 #endif /* CONFIG_IP_ROUTE_CLASSID */
2576 int __init ip_rt_init(void)
2580 #ifdef CONFIG_IP_ROUTE_CLASSID
2581 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
2583 panic("IP: failed to allocate ip_rt_acct\n");
2586 ipv4_dst_ops.kmem_cachep =
2587 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
2588 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
2590 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
2592 if (dst_entries_init(&ipv4_dst_ops) < 0)
2593 panic("IP: failed to allocate ipv4_dst_ops counter\n");
2595 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
2596 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
2598 ipv4_dst_ops.gc_thresh = ~0;
2599 ip_rt_max_size = INT_MAX;
2604 if (ip_rt_proc_init())
2605 pr_err("Unable to create route proc files\n");
2608 xfrm4_init(ip_rt_max_size);
2610 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL);
2612 #ifdef CONFIG_SYSCTL
2613 register_pernet_subsys(&sysctl_route_ops);
2615 register_pernet_subsys(&rt_genid_ops);
2616 register_pernet_subsys(&ipv4_inetpeer_ops);
2620 #ifdef CONFIG_SYSCTL
2622 * We really need to sanitize the damn ipv4 init order, then all
2623 * this nonsense will go away.
2625 void __init ip_static_sysctl_init(void)
2627 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);