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 #ifdef CONFIG_PROC_FS
206 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
210 return SEQ_START_TOKEN;
213 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
219 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
223 static int rt_cache_seq_show(struct seq_file *seq, void *v)
225 if (v == SEQ_START_TOKEN)
226 seq_printf(seq, "%-127s\n",
227 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
228 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
233 static const struct seq_operations rt_cache_seq_ops = {
234 .start = rt_cache_seq_start,
235 .next = rt_cache_seq_next,
236 .stop = rt_cache_seq_stop,
237 .show = rt_cache_seq_show,
240 static int rt_cache_seq_open(struct inode *inode, struct file *file)
242 return seq_open(file, &rt_cache_seq_ops);
245 static const struct file_operations rt_cache_seq_fops = {
246 .owner = THIS_MODULE,
247 .open = rt_cache_seq_open,
250 .release = seq_release,
254 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
259 return SEQ_START_TOKEN;
261 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
262 if (!cpu_possible(cpu))
265 return &per_cpu(rt_cache_stat, cpu);
270 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
274 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
275 if (!cpu_possible(cpu))
278 return &per_cpu(rt_cache_stat, cpu);
284 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
289 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
291 struct rt_cache_stat *st = v;
293 if (v == SEQ_START_TOKEN) {
294 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");
298 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
299 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
300 dst_entries_get_slow(&ipv4_dst_ops),
323 static const struct seq_operations rt_cpu_seq_ops = {
324 .start = rt_cpu_seq_start,
325 .next = rt_cpu_seq_next,
326 .stop = rt_cpu_seq_stop,
327 .show = rt_cpu_seq_show,
331 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
333 return seq_open(file, &rt_cpu_seq_ops);
336 static const struct file_operations rt_cpu_seq_fops = {
337 .owner = THIS_MODULE,
338 .open = rt_cpu_seq_open,
341 .release = seq_release,
344 #ifdef CONFIG_IP_ROUTE_CLASSID
345 static int rt_acct_proc_show(struct seq_file *m, void *v)
347 struct ip_rt_acct *dst, *src;
350 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
354 for_each_possible_cpu(i) {
355 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
356 for (j = 0; j < 256; j++) {
357 dst[j].o_bytes += src[j].o_bytes;
358 dst[j].o_packets += src[j].o_packets;
359 dst[j].i_bytes += src[j].i_bytes;
360 dst[j].i_packets += src[j].i_packets;
364 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
369 static int rt_acct_proc_open(struct inode *inode, struct file *file)
371 return single_open(file, rt_acct_proc_show, NULL);
374 static const struct file_operations rt_acct_proc_fops = {
375 .owner = THIS_MODULE,
376 .open = rt_acct_proc_open,
379 .release = single_release,
383 static int __net_init ip_rt_do_proc_init(struct net *net)
385 struct proc_dir_entry *pde;
387 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
392 pde = proc_create("rt_cache", S_IRUGO,
393 net->proc_net_stat, &rt_cpu_seq_fops);
397 #ifdef CONFIG_IP_ROUTE_CLASSID
398 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
404 #ifdef CONFIG_IP_ROUTE_CLASSID
406 remove_proc_entry("rt_cache", net->proc_net_stat);
409 remove_proc_entry("rt_cache", net->proc_net);
414 static void __net_exit ip_rt_do_proc_exit(struct net *net)
416 remove_proc_entry("rt_cache", net->proc_net_stat);
417 remove_proc_entry("rt_cache", net->proc_net);
418 #ifdef CONFIG_IP_ROUTE_CLASSID
419 remove_proc_entry("rt_acct", net->proc_net);
423 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
424 .init = ip_rt_do_proc_init,
425 .exit = ip_rt_do_proc_exit,
428 static int __init ip_rt_proc_init(void)
430 return register_pernet_subsys(&ip_rt_proc_ops);
434 static inline int ip_rt_proc_init(void)
438 #endif /* CONFIG_PROC_FS */
440 static inline bool rt_is_expired(const struct rtable *rth)
442 return rth->rt_genid != rt_genid(dev_net(rth->dst.dev));
445 void rt_cache_flush(struct net *net)
450 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
454 struct net_device *dev = dst->dev;
455 const __be32 *pkey = daddr;
456 const struct rtable *rt;
459 rt = (const struct rtable *) dst;
461 pkey = (const __be32 *) &rt->rt_gateway;
463 pkey = &ip_hdr(skb)->daddr;
465 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
468 return neigh_create(&arp_tbl, pkey, dev);
472 * Peer allocation may fail only in serious out-of-memory conditions. However
473 * we still can generate some output.
474 * Random ID selection looks a bit dangerous because we have no chances to
475 * select ID being unique in a reasonable period of time.
476 * But broken packet identifier may be better than no packet at all.
478 static void ip_select_fb_ident(struct iphdr *iph)
480 static DEFINE_SPINLOCK(ip_fb_id_lock);
481 static u32 ip_fallback_id;
484 spin_lock_bh(&ip_fb_id_lock);
485 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
486 iph->id = htons(salt & 0xFFFF);
487 ip_fallback_id = salt;
488 spin_unlock_bh(&ip_fb_id_lock);
491 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
493 struct net *net = dev_net(dst->dev);
494 struct inet_peer *peer;
496 peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
498 iph->id = htons(inet_getid(peer, more));
503 ip_select_fb_ident(iph);
505 EXPORT_SYMBOL(__ip_select_ident);
507 static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk,
508 const struct iphdr *iph,
510 u8 prot, u32 mark, int flow_flags)
513 const struct inet_sock *inet = inet_sk(sk);
515 oif = sk->sk_bound_dev_if;
517 tos = RT_CONN_FLAGS(sk);
518 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
520 flowi4_init_output(fl4, oif, mark, tos,
521 RT_SCOPE_UNIVERSE, prot,
523 iph->daddr, iph->saddr, 0, 0);
526 static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
527 const struct sock *sk)
529 const struct iphdr *iph = ip_hdr(skb);
530 int oif = skb->dev->ifindex;
531 u8 tos = RT_TOS(iph->tos);
532 u8 prot = iph->protocol;
533 u32 mark = skb->mark;
535 __build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0);
538 static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
540 const struct inet_sock *inet = inet_sk(sk);
541 const struct ip_options_rcu *inet_opt;
542 __be32 daddr = inet->inet_daddr;
545 inet_opt = rcu_dereference(inet->inet_opt);
546 if (inet_opt && inet_opt->opt.srr)
547 daddr = inet_opt->opt.faddr;
548 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
549 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
550 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
551 inet_sk_flowi_flags(sk),
552 daddr, inet->inet_saddr, 0, 0);
556 static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
557 const struct sk_buff *skb)
560 build_skb_flow_key(fl4, skb, sk);
562 build_sk_flow_key(fl4, sk);
565 static inline void rt_free(struct rtable *rt)
567 call_rcu(&rt->dst.rcu_head, dst_rcu_free);
570 static DEFINE_SPINLOCK(fnhe_lock);
572 static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
574 struct fib_nh_exception *fnhe, *oldest;
577 oldest = rcu_dereference(hash->chain);
578 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
579 fnhe = rcu_dereference(fnhe->fnhe_next)) {
580 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
583 orig = rcu_dereference(oldest->fnhe_rth);
585 RCU_INIT_POINTER(oldest->fnhe_rth, NULL);
591 static inline u32 fnhe_hashfun(__be32 daddr)
595 hval = (__force u32) daddr;
596 hval ^= (hval >> 11) ^ (hval >> 22);
598 return hval & (FNHE_HASH_SIZE - 1);
601 static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
602 u32 pmtu, unsigned long expires)
604 struct fnhe_hash_bucket *hash;
605 struct fib_nh_exception *fnhe;
607 u32 hval = fnhe_hashfun(daddr);
609 spin_lock_bh(&fnhe_lock);
611 hash = nh->nh_exceptions;
613 hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC);
616 nh->nh_exceptions = hash;
622 for (fnhe = rcu_dereference(hash->chain); fnhe;
623 fnhe = rcu_dereference(fnhe->fnhe_next)) {
624 if (fnhe->fnhe_daddr == daddr)
633 fnhe->fnhe_pmtu = pmtu;
634 fnhe->fnhe_expires = expires;
637 if (depth > FNHE_RECLAIM_DEPTH)
638 fnhe = fnhe_oldest(hash);
640 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
644 fnhe->fnhe_next = hash->chain;
645 rcu_assign_pointer(hash->chain, fnhe);
647 fnhe->fnhe_daddr = daddr;
649 fnhe->fnhe_pmtu = pmtu;
650 fnhe->fnhe_expires = expires;
653 fnhe->fnhe_stamp = jiffies;
656 spin_unlock_bh(&fnhe_lock);
660 static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4,
663 __be32 new_gw = icmp_hdr(skb)->un.gateway;
664 __be32 old_gw = ip_hdr(skb)->saddr;
665 struct net_device *dev = skb->dev;
666 struct in_device *in_dev;
667 struct fib_result res;
671 switch (icmp_hdr(skb)->code & 7) {
673 case ICMP_REDIR_NETTOS:
674 case ICMP_REDIR_HOST:
675 case ICMP_REDIR_HOSTTOS:
682 if (rt->rt_gateway != old_gw)
685 in_dev = __in_dev_get_rcu(dev);
690 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
691 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
692 ipv4_is_zeronet(new_gw))
693 goto reject_redirect;
695 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
696 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
697 goto reject_redirect;
698 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
699 goto reject_redirect;
701 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
702 goto reject_redirect;
705 n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw);
707 if (!(n->nud_state & NUD_VALID)) {
708 neigh_event_send(n, NULL);
710 if (fib_lookup(net, fl4, &res) == 0) {
711 struct fib_nh *nh = &FIB_RES_NH(res);
713 update_or_create_fnhe(nh, fl4->daddr, new_gw,
717 rt->dst.obsolete = DST_OBSOLETE_KILL;
718 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
725 #ifdef CONFIG_IP_ROUTE_VERBOSE
726 if (IN_DEV_LOG_MARTIANS(in_dev)) {
727 const struct iphdr *iph = (const struct iphdr *) skb->data;
728 __be32 daddr = iph->daddr;
729 __be32 saddr = iph->saddr;
731 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
732 " Advised path = %pI4 -> %pI4\n",
733 &old_gw, dev->name, &new_gw,
740 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
745 rt = (struct rtable *) dst;
747 ip_rt_build_flow_key(&fl4, sk, skb);
748 __ip_do_redirect(rt, skb, &fl4, true);
751 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
753 struct rtable *rt = (struct rtable *)dst;
754 struct dst_entry *ret = dst;
757 if (dst->obsolete > 0) {
760 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
771 * 1. The first ip_rt_redirect_number redirects are sent
772 * with exponential backoff, then we stop sending them at all,
773 * assuming that the host ignores our redirects.
774 * 2. If we did not see packets requiring redirects
775 * during ip_rt_redirect_silence, we assume that the host
776 * forgot redirected route and start to send redirects again.
778 * This algorithm is much cheaper and more intelligent than dumb load limiting
781 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
782 * and "frag. need" (breaks PMTU discovery) in icmp.c.
785 void ip_rt_send_redirect(struct sk_buff *skb)
787 struct rtable *rt = skb_rtable(skb);
788 struct in_device *in_dev;
789 struct inet_peer *peer;
794 in_dev = __in_dev_get_rcu(rt->dst.dev);
795 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
799 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
802 net = dev_net(rt->dst.dev);
803 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
805 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST,
806 rt_nexthop(rt, ip_hdr(skb)->daddr));
810 /* No redirected packets during ip_rt_redirect_silence;
811 * reset the algorithm.
813 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
814 peer->rate_tokens = 0;
816 /* Too many ignored redirects; do not send anything
817 * set dst.rate_last to the last seen redirected packet.
819 if (peer->rate_tokens >= ip_rt_redirect_number) {
820 peer->rate_last = jiffies;
824 /* Check for load limit; set rate_last to the latest sent
827 if (peer->rate_tokens == 0 ||
830 (ip_rt_redirect_load << peer->rate_tokens)))) {
831 __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr);
833 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw);
834 peer->rate_last = jiffies;
836 #ifdef CONFIG_IP_ROUTE_VERBOSE
838 peer->rate_tokens == ip_rt_redirect_number)
839 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
840 &ip_hdr(skb)->saddr, inet_iif(skb),
841 &ip_hdr(skb)->daddr, &gw);
848 static int ip_error(struct sk_buff *skb)
850 struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
851 struct rtable *rt = skb_rtable(skb);
852 struct inet_peer *peer;
858 net = dev_net(rt->dst.dev);
859 if (!IN_DEV_FORWARD(in_dev)) {
860 switch (rt->dst.error) {
862 IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS);
866 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
872 switch (rt->dst.error) {
877 code = ICMP_HOST_UNREACH;
880 code = ICMP_NET_UNREACH;
881 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
884 code = ICMP_PKT_FILTERED;
888 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
893 peer->rate_tokens += now - peer->rate_last;
894 if (peer->rate_tokens > ip_rt_error_burst)
895 peer->rate_tokens = ip_rt_error_burst;
896 peer->rate_last = now;
897 if (peer->rate_tokens >= ip_rt_error_cost)
898 peer->rate_tokens -= ip_rt_error_cost;
904 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
910 static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
912 struct dst_entry *dst = &rt->dst;
913 struct fib_result res;
915 if (dst->dev->mtu < mtu)
918 if (mtu < ip_rt_min_pmtu)
919 mtu = ip_rt_min_pmtu;
922 dst->obsolete = DST_OBSOLETE_KILL;
925 dst->expires = max(1UL, jiffies + ip_rt_mtu_expires);
929 if (fib_lookup(dev_net(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);
938 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
939 struct sk_buff *skb, u32 mtu)
941 struct rtable *rt = (struct rtable *) dst;
944 ip_rt_build_flow_key(&fl4, sk, skb);
945 __ip_rt_update_pmtu(rt, &fl4, mtu);
948 void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
949 int oif, u32 mark, u8 protocol, int flow_flags)
951 const struct iphdr *iph = (const struct iphdr *) skb->data;
955 __build_flow_key(&fl4, NULL, iph, oif,
956 RT_TOS(iph->tos), protocol, mark, flow_flags);
957 rt = __ip_route_output_key(net, &fl4);
959 __ip_rt_update_pmtu(rt, &fl4, mtu);
963 EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
965 void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
967 const struct iphdr *iph = (const struct iphdr *) skb->data;
971 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
972 rt = __ip_route_output_key(sock_net(sk), &fl4);
974 __ip_rt_update_pmtu(rt, &fl4, mtu);
978 EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
980 void ipv4_redirect(struct sk_buff *skb, struct net *net,
981 int oif, u32 mark, u8 protocol, int flow_flags)
983 const struct iphdr *iph = (const struct iphdr *) skb->data;
987 __build_flow_key(&fl4, NULL, iph, oif,
988 RT_TOS(iph->tos), protocol, mark, flow_flags);
989 rt = __ip_route_output_key(net, &fl4);
991 __ip_do_redirect(rt, skb, &fl4, false);
995 EXPORT_SYMBOL_GPL(ipv4_redirect);
997 void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
999 const struct iphdr *iph = (const struct iphdr *) skb->data;
1003 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
1004 rt = __ip_route_output_key(sock_net(sk), &fl4);
1006 __ip_do_redirect(rt, skb, &fl4, false);
1010 EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1012 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1014 struct rtable *rt = (struct rtable *) dst;
1016 /* All IPV4 dsts are created with ->obsolete set to the value
1017 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1018 * into this function always.
1020 * When a PMTU/redirect information update invalidates a
1021 * route, this is indicated by setting obsolete to
1022 * DST_OBSOLETE_KILL.
1024 if (dst->obsolete == DST_OBSOLETE_KILL || rt_is_expired(rt))
1029 static void ipv4_link_failure(struct sk_buff *skb)
1033 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1035 rt = skb_rtable(skb);
1037 dst_set_expires(&rt->dst, 0);
1040 static int ip_rt_bug(struct sk_buff *skb)
1042 pr_debug("%s: %pI4 -> %pI4, %s\n",
1043 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1044 skb->dev ? skb->dev->name : "?");
1051 We do not cache source address of outgoing interface,
1052 because it is used only by IP RR, TS and SRR options,
1053 so that it out of fast path.
1055 BTW remember: "addr" is allowed to be not aligned
1059 void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
1063 if (rt_is_output_route(rt))
1064 src = ip_hdr(skb)->saddr;
1066 struct fib_result res;
1072 memset(&fl4, 0, sizeof(fl4));
1073 fl4.daddr = iph->daddr;
1074 fl4.saddr = iph->saddr;
1075 fl4.flowi4_tos = RT_TOS(iph->tos);
1076 fl4.flowi4_oif = rt->dst.dev->ifindex;
1077 fl4.flowi4_iif = skb->dev->ifindex;
1078 fl4.flowi4_mark = skb->mark;
1081 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0)
1082 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
1084 src = inet_select_addr(rt->dst.dev,
1085 rt_nexthop(rt, iph->daddr),
1089 memcpy(addr, &src, 4);
1092 #ifdef CONFIG_IP_ROUTE_CLASSID
1093 static void set_class_tag(struct rtable *rt, u32 tag)
1095 if (!(rt->dst.tclassid & 0xFFFF))
1096 rt->dst.tclassid |= tag & 0xFFFF;
1097 if (!(rt->dst.tclassid & 0xFFFF0000))
1098 rt->dst.tclassid |= tag & 0xFFFF0000;
1102 static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1104 unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
1107 advmss = max_t(unsigned int, dst->dev->mtu - 40,
1109 if (advmss > 65535 - 40)
1110 advmss = 65535 - 40;
1115 static unsigned int ipv4_mtu(const struct dst_entry *dst)
1117 const struct rtable *rt = (const struct rtable *) dst;
1118 unsigned int mtu = rt->rt_pmtu;
1120 if (!mtu || time_after_eq(jiffies, rt->dst.expires))
1121 mtu = dst_metric_raw(dst, RTAX_MTU);
1123 if (mtu && rt_is_output_route(rt))
1126 mtu = dst->dev->mtu;
1128 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
1129 if (rt->rt_uses_gateway && mtu > 576)
1133 if (mtu > IP_MAX_MTU)
1139 static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
1141 struct fnhe_hash_bucket *hash = nh->nh_exceptions;
1142 struct fib_nh_exception *fnhe;
1148 hval = fnhe_hashfun(daddr);
1150 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1151 fnhe = rcu_dereference(fnhe->fnhe_next)) {
1152 if (fnhe->fnhe_daddr == daddr)
1158 static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
1163 spin_lock_bh(&fnhe_lock);
1165 if (daddr == fnhe->fnhe_daddr) {
1166 struct rtable *orig;
1168 if (fnhe->fnhe_pmtu) {
1169 unsigned long expires = fnhe->fnhe_expires;
1170 unsigned long diff = expires - jiffies;
1172 if (time_before(jiffies, expires)) {
1173 rt->rt_pmtu = fnhe->fnhe_pmtu;
1174 dst_set_expires(&rt->dst, diff);
1177 if (fnhe->fnhe_gw) {
1178 rt->rt_flags |= RTCF_REDIRECTED;
1179 rt->rt_gateway = fnhe->fnhe_gw;
1180 rt->rt_uses_gateway = 1;
1181 } else if (!rt->rt_gateway)
1182 rt->rt_gateway = daddr;
1184 orig = rcu_dereference(fnhe->fnhe_rth);
1185 rcu_assign_pointer(fnhe->fnhe_rth, rt);
1189 fnhe->fnhe_stamp = jiffies;
1192 spin_unlock_bh(&fnhe_lock);
1197 static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt)
1199 struct rtable *orig, *prev, **p;
1202 if (rt_is_input_route(rt)) {
1203 p = (struct rtable **)&nh->nh_rth_input;
1205 p = (struct rtable **)__this_cpu_ptr(nh->nh_pcpu_rth_output);
1209 prev = cmpxchg(p, orig, rt);
1219 static DEFINE_SPINLOCK(rt_uncached_lock);
1220 static LIST_HEAD(rt_uncached_list);
1222 static void rt_add_uncached_list(struct rtable *rt)
1224 spin_lock_bh(&rt_uncached_lock);
1225 list_add_tail(&rt->rt_uncached, &rt_uncached_list);
1226 spin_unlock_bh(&rt_uncached_lock);
1229 static void ipv4_dst_destroy(struct dst_entry *dst)
1231 struct rtable *rt = (struct rtable *) dst;
1233 if (!list_empty(&rt->rt_uncached)) {
1234 spin_lock_bh(&rt_uncached_lock);
1235 list_del(&rt->rt_uncached);
1236 spin_unlock_bh(&rt_uncached_lock);
1240 void rt_flush_dev(struct net_device *dev)
1242 if (!list_empty(&rt_uncached_list)) {
1243 struct net *net = dev_net(dev);
1246 spin_lock_bh(&rt_uncached_lock);
1247 list_for_each_entry(rt, &rt_uncached_list, rt_uncached) {
1248 if (rt->dst.dev != dev)
1250 rt->dst.dev = net->loopback_dev;
1251 dev_hold(rt->dst.dev);
1254 spin_unlock_bh(&rt_uncached_lock);
1258 static bool rt_cache_valid(const struct rtable *rt)
1261 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1265 static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
1266 const struct fib_result *res,
1267 struct fib_nh_exception *fnhe,
1268 struct fib_info *fi, u16 type, u32 itag)
1270 bool cached = false;
1273 struct fib_nh *nh = &FIB_RES_NH(*res);
1275 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) {
1276 rt->rt_gateway = nh->nh_gw;
1277 rt->rt_uses_gateway = 1;
1279 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
1280 #ifdef CONFIG_IP_ROUTE_CLASSID
1281 rt->dst.tclassid = nh->nh_tclassid;
1284 cached = rt_bind_exception(rt, fnhe, daddr);
1285 else if (!(rt->dst.flags & DST_NOCACHE))
1286 cached = rt_cache_route(nh, rt);
1287 if (unlikely(!cached)) {
1288 /* Routes we intend to cache in nexthop exception or
1289 * FIB nexthop have the DST_NOCACHE bit clear.
1290 * However, if we are unsuccessful at storing this
1291 * route into the cache we really need to set it.
1293 rt->dst.flags |= DST_NOCACHE;
1294 if (!rt->rt_gateway)
1295 rt->rt_gateway = daddr;
1296 rt_add_uncached_list(rt);
1299 rt_add_uncached_list(rt);
1301 #ifdef CONFIG_IP_ROUTE_CLASSID
1302 #ifdef CONFIG_IP_MULTIPLE_TABLES
1303 set_class_tag(rt, res->tclassid);
1305 set_class_tag(rt, itag);
1309 static struct rtable *rt_dst_alloc(struct net_device *dev,
1310 bool nopolicy, bool noxfrm, bool will_cache)
1312 return dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
1313 (will_cache ? 0 : (DST_HOST | DST_NOCACHE)) |
1314 (nopolicy ? DST_NOPOLICY : 0) |
1315 (noxfrm ? DST_NOXFRM : 0));
1318 /* called in rcu_read_lock() section */
1319 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1320 u8 tos, struct net_device *dev, int our)
1323 struct in_device *in_dev = __in_dev_get_rcu(dev);
1327 /* Primary sanity checks. */
1332 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1333 skb->protocol != htons(ETH_P_IP))
1336 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1337 if (ipv4_is_loopback(saddr))
1340 if (ipv4_is_zeronet(saddr)) {
1341 if (!ipv4_is_local_multicast(daddr))
1344 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1349 rth = rt_dst_alloc(dev_net(dev)->loopback_dev,
1350 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false);
1354 #ifdef CONFIG_IP_ROUTE_CLASSID
1355 rth->dst.tclassid = itag;
1357 rth->dst.output = ip_rt_bug;
1359 rth->rt_genid = rt_genid(dev_net(dev));
1360 rth->rt_flags = RTCF_MULTICAST;
1361 rth->rt_type = RTN_MULTICAST;
1362 rth->rt_is_input= 1;
1365 rth->rt_gateway = 0;
1366 rth->rt_uses_gateway = 0;
1367 INIT_LIST_HEAD(&rth->rt_uncached);
1369 rth->dst.input= ip_local_deliver;
1370 rth->rt_flags |= RTCF_LOCAL;
1373 #ifdef CONFIG_IP_MROUTE
1374 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1375 rth->dst.input = ip_mr_input;
1377 RT_CACHE_STAT_INC(in_slow_mc);
1379 skb_dst_set(skb, &rth->dst);
1391 static void ip_handle_martian_source(struct net_device *dev,
1392 struct in_device *in_dev,
1393 struct sk_buff *skb,
1397 RT_CACHE_STAT_INC(in_martian_src);
1398 #ifdef CONFIG_IP_ROUTE_VERBOSE
1399 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1401 * RFC1812 recommendation, if source is martian,
1402 * the only hint is MAC header.
1404 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
1405 &daddr, &saddr, dev->name);
1406 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1407 print_hex_dump(KERN_WARNING, "ll header: ",
1408 DUMP_PREFIX_OFFSET, 16, 1,
1409 skb_mac_header(skb),
1410 dev->hard_header_len, true);
1416 /* called in rcu_read_lock() section */
1417 static int __mkroute_input(struct sk_buff *skb,
1418 const struct fib_result *res,
1419 struct in_device *in_dev,
1420 __be32 daddr, __be32 saddr, u32 tos)
1424 struct in_device *out_dev;
1425 unsigned int flags = 0;
1429 /* get a working reference to the output device */
1430 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1431 if (out_dev == NULL) {
1432 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
1436 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
1437 in_dev->dev, in_dev, &itag);
1439 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1445 do_cache = res->fi && !itag;
1446 if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
1447 (IN_DEV_SHARED_MEDIA(out_dev) ||
1448 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) {
1449 flags |= RTCF_DOREDIRECT;
1453 if (skb->protocol != htons(ETH_P_IP)) {
1454 /* Not IP (i.e. ARP). Do not create route, if it is
1455 * invalid for proxy arp. DNAT routes are always valid.
1457 * Proxy arp feature have been extended to allow, ARP
1458 * replies back to the same interface, to support
1459 * Private VLAN switch technologies. See arp.c.
1461 if (out_dev == in_dev &&
1462 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1469 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1470 if (rt_cache_valid(rth)) {
1471 skb_dst_set_noref(skb, &rth->dst);
1476 rth = rt_dst_alloc(out_dev->dev,
1477 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1478 IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache);
1484 rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
1485 rth->rt_flags = flags;
1486 rth->rt_type = res->type;
1487 rth->rt_is_input = 1;
1490 rth->rt_gateway = 0;
1491 rth->rt_uses_gateway = 0;
1492 INIT_LIST_HEAD(&rth->rt_uncached);
1494 rth->dst.input = ip_forward;
1495 rth->dst.output = ip_output;
1497 rt_set_nexthop(rth, daddr, res, NULL, res->fi, res->type, itag);
1498 skb_dst_set(skb, &rth->dst);
1505 static int ip_mkroute_input(struct sk_buff *skb,
1506 struct fib_result *res,
1507 const struct flowi4 *fl4,
1508 struct in_device *in_dev,
1509 __be32 daddr, __be32 saddr, u32 tos)
1511 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1512 if (res->fi && res->fi->fib_nhs > 1)
1513 fib_select_multipath(res);
1516 /* create a routing cache entry */
1517 return __mkroute_input(skb, res, in_dev, daddr, saddr, tos);
1521 * NOTE. We drop all the packets that has local source
1522 * addresses, because every properly looped back packet
1523 * must have correct destination already attached by output routine.
1525 * Such approach solves two big problems:
1526 * 1. Not simplex devices are handled properly.
1527 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1528 * called with rcu_read_lock()
1531 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1532 u8 tos, struct net_device *dev)
1534 struct fib_result res;
1535 struct in_device *in_dev = __in_dev_get_rcu(dev);
1537 unsigned int flags = 0;
1541 struct net *net = dev_net(dev);
1544 /* IP on this device is disabled. */
1549 /* Check for the most weird martians, which can be not detected
1553 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
1554 goto martian_source;
1557 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
1560 /* Accept zero addresses only to limited broadcast;
1561 * I even do not know to fix it or not. Waiting for complains :-)
1563 if (ipv4_is_zeronet(saddr))
1564 goto martian_source;
1566 if (ipv4_is_zeronet(daddr))
1567 goto martian_destination;
1569 /* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(),
1570 * and call it once if daddr or/and saddr are loopback addresses
1572 if (ipv4_is_loopback(daddr)) {
1573 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
1574 goto martian_destination;
1575 } else if (ipv4_is_loopback(saddr)) {
1576 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
1577 goto martian_source;
1581 * Now we are ready to route packet.
1584 fl4.flowi4_iif = dev->ifindex;
1585 fl4.flowi4_mark = skb->mark;
1586 fl4.flowi4_tos = tos;
1587 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
1590 err = fib_lookup(net, &fl4, &res);
1594 RT_CACHE_STAT_INC(in_slow_tot);
1596 if (res.type == RTN_BROADCAST)
1599 if (res.type == RTN_LOCAL) {
1600 err = fib_validate_source(skb, saddr, daddr, tos,
1602 dev, in_dev, &itag);
1604 goto martian_source_keep_err;
1608 if (!IN_DEV_FORWARD(in_dev))
1610 if (res.type != RTN_UNICAST)
1611 goto martian_destination;
1613 err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos);
1617 if (skb->protocol != htons(ETH_P_IP))
1620 if (!ipv4_is_zeronet(saddr)) {
1621 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1624 goto martian_source_keep_err;
1626 flags |= RTCF_BROADCAST;
1627 res.type = RTN_BROADCAST;
1628 RT_CACHE_STAT_INC(in_brd);
1634 rth = rcu_dereference(FIB_RES_NH(res).nh_rth_input);
1635 if (rt_cache_valid(rth)) {
1636 skb_dst_set_noref(skb, &rth->dst);
1644 rth = rt_dst_alloc(net->loopback_dev,
1645 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache);
1649 rth->dst.input= ip_local_deliver;
1650 rth->dst.output= ip_rt_bug;
1651 #ifdef CONFIG_IP_ROUTE_CLASSID
1652 rth->dst.tclassid = itag;
1655 rth->rt_genid = rt_genid(net);
1656 rth->rt_flags = flags|RTCF_LOCAL;
1657 rth->rt_type = res.type;
1658 rth->rt_is_input = 1;
1661 rth->rt_gateway = 0;
1662 rth->rt_uses_gateway = 0;
1663 INIT_LIST_HEAD(&rth->rt_uncached);
1664 if (res.type == RTN_UNREACHABLE) {
1665 rth->dst.input= ip_error;
1666 rth->dst.error= -err;
1667 rth->rt_flags &= ~RTCF_LOCAL;
1670 rt_cache_route(&FIB_RES_NH(res), rth);
1671 skb_dst_set(skb, &rth->dst);
1676 RT_CACHE_STAT_INC(in_no_route);
1677 res.type = RTN_UNREACHABLE;
1683 * Do not cache martian addresses: they should be logged (RFC1812)
1685 martian_destination:
1686 RT_CACHE_STAT_INC(in_martian_dst);
1687 #ifdef CONFIG_IP_ROUTE_VERBOSE
1688 if (IN_DEV_LOG_MARTIANS(in_dev))
1689 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
1690 &daddr, &saddr, dev->name);
1703 martian_source_keep_err:
1704 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
1708 int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1709 u8 tos, struct net_device *dev)
1715 /* Multicast recognition logic is moved from route cache to here.
1716 The problem was that too many Ethernet cards have broken/missing
1717 hardware multicast filters :-( As result the host on multicasting
1718 network acquires a lot of useless route cache entries, sort of
1719 SDR messages from all the world. Now we try to get rid of them.
1720 Really, provided software IP multicast filter is organized
1721 reasonably (at least, hashed), it does not result in a slowdown
1722 comparing with route cache reject entries.
1723 Note, that multicast routers are not affected, because
1724 route cache entry is created eventually.
1726 if (ipv4_is_multicast(daddr)) {
1727 struct in_device *in_dev = __in_dev_get_rcu(dev);
1730 int our = ip_check_mc_rcu(in_dev, daddr, saddr,
1731 ip_hdr(skb)->protocol);
1733 #ifdef CONFIG_IP_MROUTE
1735 (!ipv4_is_local_multicast(daddr) &&
1736 IN_DEV_MFORWARD(in_dev))
1739 int res = ip_route_input_mc(skb, daddr, saddr,
1748 res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
1752 EXPORT_SYMBOL(ip_route_input_noref);
1754 /* called with rcu_read_lock() */
1755 static struct rtable *__mkroute_output(const struct fib_result *res,
1756 const struct flowi4 *fl4, int orig_oif,
1757 struct net_device *dev_out,
1760 struct fib_info *fi = res->fi;
1761 struct fib_nh_exception *fnhe;
1762 struct in_device *in_dev;
1763 u16 type = res->type;
1767 in_dev = __in_dev_get_rcu(dev_out);
1769 return ERR_PTR(-EINVAL);
1771 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1772 if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
1773 return ERR_PTR(-EINVAL);
1775 if (ipv4_is_lbcast(fl4->daddr))
1776 type = RTN_BROADCAST;
1777 else if (ipv4_is_multicast(fl4->daddr))
1778 type = RTN_MULTICAST;
1779 else if (ipv4_is_zeronet(fl4->daddr))
1780 return ERR_PTR(-EINVAL);
1782 if (dev_out->flags & IFF_LOOPBACK)
1783 flags |= RTCF_LOCAL;
1785 if (type == RTN_BROADCAST) {
1786 flags |= RTCF_BROADCAST | RTCF_LOCAL;
1788 } else if (type == RTN_MULTICAST) {
1789 flags |= RTCF_MULTICAST | RTCF_LOCAL;
1790 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
1792 flags &= ~RTCF_LOCAL;
1793 /* If multicast route do not exist use
1794 * default one, but do not gateway in this case.
1797 if (fi && res->prefixlen < 4)
1802 do_cache = fi != NULL;
1804 struct rtable __rcu **prth;
1805 struct fib_nh *nh = &FIB_RES_NH(*res);
1807 fnhe = find_exception(nh, fl4->daddr);
1809 prth = &fnhe->fnhe_rth;
1811 if (unlikely(fl4->flowi4_flags &
1812 FLOWI_FLAG_KNOWN_NH &&
1814 nh->nh_scope == RT_SCOPE_LINK))) {
1818 prth = __this_cpu_ptr(nh->nh_pcpu_rth_output);
1820 rth = rcu_dereference(*prth);
1821 if (rt_cache_valid(rth)) {
1822 dst_hold(&rth->dst);
1828 rth = rt_dst_alloc(dev_out,
1829 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1830 IN_DEV_CONF_GET(in_dev, NOXFRM),
1833 return ERR_PTR(-ENOBUFS);
1835 rth->dst.output = ip_output;
1837 rth->rt_genid = rt_genid(dev_net(dev_out));
1838 rth->rt_flags = flags;
1839 rth->rt_type = type;
1840 rth->rt_is_input = 0;
1841 rth->rt_iif = orig_oif ? : 0;
1843 rth->rt_gateway = 0;
1844 rth->rt_uses_gateway = 0;
1845 INIT_LIST_HEAD(&rth->rt_uncached);
1847 RT_CACHE_STAT_INC(out_slow_tot);
1849 if (flags & RTCF_LOCAL)
1850 rth->dst.input = ip_local_deliver;
1851 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
1852 if (flags & RTCF_LOCAL &&
1853 !(dev_out->flags & IFF_LOOPBACK)) {
1854 rth->dst.output = ip_mc_output;
1855 RT_CACHE_STAT_INC(out_slow_mc);
1857 #ifdef CONFIG_IP_MROUTE
1858 if (type == RTN_MULTICAST) {
1859 if (IN_DEV_MFORWARD(in_dev) &&
1860 !ipv4_is_local_multicast(fl4->daddr)) {
1861 rth->dst.input = ip_mr_input;
1862 rth->dst.output = ip_mc_output;
1868 rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0);
1874 * Major route resolver routine.
1877 struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
1879 struct net_device *dev_out = NULL;
1880 __u8 tos = RT_FL_TOS(fl4);
1881 unsigned int flags = 0;
1882 struct fib_result res;
1890 orig_oif = fl4->flowi4_oif;
1892 fl4->flowi4_iif = LOOPBACK_IFINDEX;
1893 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
1894 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
1895 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
1899 rth = ERR_PTR(-EINVAL);
1900 if (ipv4_is_multicast(fl4->saddr) ||
1901 ipv4_is_lbcast(fl4->saddr) ||
1902 ipv4_is_zeronet(fl4->saddr))
1905 /* I removed check for oif == dev_out->oif here.
1906 It was wrong for two reasons:
1907 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
1908 is assigned to multiple interfaces.
1909 2. Moreover, we are allowed to send packets with saddr
1910 of another iface. --ANK
1913 if (fl4->flowi4_oif == 0 &&
1914 (ipv4_is_multicast(fl4->daddr) ||
1915 ipv4_is_lbcast(fl4->daddr))) {
1916 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1917 dev_out = __ip_dev_find(net, fl4->saddr, false);
1918 if (dev_out == NULL)
1921 /* Special hack: user can direct multicasts
1922 and limited broadcast via necessary interface
1923 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
1924 This hack is not just for fun, it allows
1925 vic,vat and friends to work.
1926 They bind socket to loopback, set ttl to zero
1927 and expect that it will work.
1928 From the viewpoint of routing cache they are broken,
1929 because we are not allowed to build multicast path
1930 with loopback source addr (look, routing cache
1931 cannot know, that ttl is zero, so that packet
1932 will not leave this host and route is valid).
1933 Luckily, this hack is good workaround.
1936 fl4->flowi4_oif = dev_out->ifindex;
1940 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
1941 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1942 if (!__ip_dev_find(net, fl4->saddr, false))
1948 if (fl4->flowi4_oif) {
1949 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
1950 rth = ERR_PTR(-ENODEV);
1951 if (dev_out == NULL)
1954 /* RACE: Check return value of inet_select_addr instead. */
1955 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
1956 rth = ERR_PTR(-ENETUNREACH);
1959 if (ipv4_is_local_multicast(fl4->daddr) ||
1960 ipv4_is_lbcast(fl4->daddr)) {
1962 fl4->saddr = inet_select_addr(dev_out, 0,
1967 if (ipv4_is_multicast(fl4->daddr))
1968 fl4->saddr = inet_select_addr(dev_out, 0,
1970 else if (!fl4->daddr)
1971 fl4->saddr = inet_select_addr(dev_out, 0,
1977 fl4->daddr = fl4->saddr;
1979 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
1980 dev_out = net->loopback_dev;
1981 fl4->flowi4_oif = LOOPBACK_IFINDEX;
1982 res.type = RTN_LOCAL;
1983 flags |= RTCF_LOCAL;
1987 if (fib_lookup(net, fl4, &res)) {
1990 if (fl4->flowi4_oif) {
1991 /* Apparently, routing tables are wrong. Assume,
1992 that the destination is on link.
1995 Because we are allowed to send to iface
1996 even if it has NO routes and NO assigned
1997 addresses. When oif is specified, routing
1998 tables are looked up with only one purpose:
1999 to catch if destination is gatewayed, rather than
2000 direct. Moreover, if MSG_DONTROUTE is set,
2001 we send packet, ignoring both routing tables
2002 and ifaddr state. --ANK
2005 We could make it even if oif is unknown,
2006 likely IPv6, but we do not.
2009 if (fl4->saddr == 0)
2010 fl4->saddr = inet_select_addr(dev_out, 0,
2012 res.type = RTN_UNICAST;
2015 rth = ERR_PTR(-ENETUNREACH);
2019 if (res.type == RTN_LOCAL) {
2021 if (res.fi->fib_prefsrc)
2022 fl4->saddr = res.fi->fib_prefsrc;
2024 fl4->saddr = fl4->daddr;
2026 dev_out = net->loopback_dev;
2027 fl4->flowi4_oif = dev_out->ifindex;
2028 flags |= RTCF_LOCAL;
2032 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2033 if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
2034 fib_select_multipath(&res);
2037 if (!res.prefixlen &&
2038 res.table->tb_num_default > 1 &&
2039 res.type == RTN_UNICAST && !fl4->flowi4_oif)
2040 fib_select_default(&res);
2043 fl4->saddr = FIB_RES_PREFSRC(net, res);
2045 dev_out = FIB_RES_DEV(res);
2046 fl4->flowi4_oif = dev_out->ifindex;
2050 rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags);
2056 EXPORT_SYMBOL_GPL(__ip_route_output_key);
2058 static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2063 static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
2065 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2067 return mtu ? : dst->dev->mtu;
2070 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
2071 struct sk_buff *skb, u32 mtu)
2075 static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
2076 struct sk_buff *skb)
2080 static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
2086 static struct dst_ops ipv4_dst_blackhole_ops = {
2088 .protocol = cpu_to_be16(ETH_P_IP),
2089 .check = ipv4_blackhole_dst_check,
2090 .mtu = ipv4_blackhole_mtu,
2091 .default_advmss = ipv4_default_advmss,
2092 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2093 .redirect = ipv4_rt_blackhole_redirect,
2094 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
2095 .neigh_lookup = ipv4_neigh_lookup,
2098 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2100 struct rtable *ort = (struct rtable *) dst_orig;
2103 rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2105 struct dst_entry *new = &rt->dst;
2108 new->input = dst_discard;
2109 new->output = dst_discard;
2111 new->dev = ort->dst.dev;
2115 rt->rt_is_input = ort->rt_is_input;
2116 rt->rt_iif = ort->rt_iif;
2117 rt->rt_pmtu = ort->rt_pmtu;
2119 rt->rt_genid = rt_genid(net);
2120 rt->rt_flags = ort->rt_flags;
2121 rt->rt_type = ort->rt_type;
2122 rt->rt_gateway = ort->rt_gateway;
2123 rt->rt_uses_gateway = ort->rt_uses_gateway;
2125 INIT_LIST_HEAD(&rt->rt_uncached);
2130 dst_release(dst_orig);
2132 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2135 struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
2138 struct rtable *rt = __ip_route_output_key(net, flp4);
2143 if (flp4->flowi4_proto)
2144 rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
2145 flowi4_to_flowi(flp4),
2150 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2152 static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
2153 struct flowi4 *fl4, struct sk_buff *skb, u32 portid,
2154 u32 seq, int event, int nowait, unsigned int flags)
2156 struct rtable *rt = skb_rtable(skb);
2158 struct nlmsghdr *nlh;
2159 unsigned long expires = 0;
2161 u32 metrics[RTAX_MAX];
2163 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
2167 r = nlmsg_data(nlh);
2168 r->rtm_family = AF_INET;
2169 r->rtm_dst_len = 32;
2171 r->rtm_tos = fl4->flowi4_tos;
2172 r->rtm_table = RT_TABLE_MAIN;
2173 if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN))
2174 goto nla_put_failure;
2175 r->rtm_type = rt->rt_type;
2176 r->rtm_scope = RT_SCOPE_UNIVERSE;
2177 r->rtm_protocol = RTPROT_UNSPEC;
2178 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2179 if (rt->rt_flags & RTCF_NOTIFY)
2180 r->rtm_flags |= RTM_F_NOTIFY;
2182 if (nla_put_be32(skb, RTA_DST, dst))
2183 goto nla_put_failure;
2185 r->rtm_src_len = 32;
2186 if (nla_put_be32(skb, RTA_SRC, src))
2187 goto nla_put_failure;
2190 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2191 goto nla_put_failure;
2192 #ifdef CONFIG_IP_ROUTE_CLASSID
2193 if (rt->dst.tclassid &&
2194 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2195 goto nla_put_failure;
2197 if (!rt_is_input_route(rt) &&
2198 fl4->saddr != src) {
2199 if (nla_put_be32(skb, RTA_PREFSRC, fl4->saddr))
2200 goto nla_put_failure;
2202 if (rt->rt_uses_gateway &&
2203 nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway))
2204 goto nla_put_failure;
2206 expires = rt->dst.expires;
2208 unsigned long now = jiffies;
2210 if (time_before(now, expires))
2216 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
2217 if (rt->rt_pmtu && expires)
2218 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2219 if (rtnetlink_put_metrics(skb, metrics) < 0)
2220 goto nla_put_failure;
2222 if (fl4->flowi4_mark &&
2223 nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark))
2224 goto nla_put_failure;
2226 error = rt->dst.error;
2228 if (rt_is_input_route(rt)) {
2229 if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))
2230 goto nla_put_failure;
2233 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
2234 goto nla_put_failure;
2236 return nlmsg_end(skb, nlh);
2239 nlmsg_cancel(skb, nlh);
2243 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
2245 struct net *net = sock_net(in_skb->sk);
2247 struct nlattr *tb[RTA_MAX+1];
2248 struct rtable *rt = NULL;
2255 struct sk_buff *skb;
2257 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2261 rtm = nlmsg_data(nlh);
2263 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2269 /* Reserve room for dummy headers, this skb can pass
2270 through good chunk of routing engine.
2272 skb_reset_mac_header(skb);
2273 skb_reset_network_header(skb);
2275 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2276 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2277 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2279 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2280 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2281 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2282 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2284 memset(&fl4, 0, sizeof(fl4));
2287 fl4.flowi4_tos = rtm->rtm_tos;
2288 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2289 fl4.flowi4_mark = mark;
2292 struct net_device *dev;
2294 dev = __dev_get_by_index(net, iif);
2300 skb->protocol = htons(ETH_P_IP);
2304 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2307 rt = skb_rtable(skb);
2308 if (err == 0 && rt->dst.error)
2309 err = -rt->dst.error;
2311 rt = ip_route_output_key(net, &fl4);
2321 skb_dst_set(skb, &rt->dst);
2322 if (rtm->rtm_flags & RTM_F_NOTIFY)
2323 rt->rt_flags |= RTCF_NOTIFY;
2325 err = rt_fill_info(net, dst, src, &fl4, skb,
2326 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
2327 RTM_NEWROUTE, 0, 0);
2331 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2340 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2345 void ip_rt_multicast_event(struct in_device *in_dev)
2347 rt_cache_flush(dev_net(in_dev->dev));
2350 #ifdef CONFIG_SYSCTL
2351 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2352 void __user *buffer,
2353 size_t *lenp, loff_t *ppos)
2356 rt_cache_flush((struct net *)__ctl->extra1);
2363 static ctl_table ipv4_route_table[] = {
2365 .procname = "gc_thresh",
2366 .data = &ipv4_dst_ops.gc_thresh,
2367 .maxlen = sizeof(int),
2369 .proc_handler = proc_dointvec,
2372 .procname = "max_size",
2373 .data = &ip_rt_max_size,
2374 .maxlen = sizeof(int),
2376 .proc_handler = proc_dointvec,
2379 /* Deprecated. Use gc_min_interval_ms */
2381 .procname = "gc_min_interval",
2382 .data = &ip_rt_gc_min_interval,
2383 .maxlen = sizeof(int),
2385 .proc_handler = proc_dointvec_jiffies,
2388 .procname = "gc_min_interval_ms",
2389 .data = &ip_rt_gc_min_interval,
2390 .maxlen = sizeof(int),
2392 .proc_handler = proc_dointvec_ms_jiffies,
2395 .procname = "gc_timeout",
2396 .data = &ip_rt_gc_timeout,
2397 .maxlen = sizeof(int),
2399 .proc_handler = proc_dointvec_jiffies,
2402 .procname = "gc_interval",
2403 .data = &ip_rt_gc_interval,
2404 .maxlen = sizeof(int),
2406 .proc_handler = proc_dointvec_jiffies,
2409 .procname = "redirect_load",
2410 .data = &ip_rt_redirect_load,
2411 .maxlen = sizeof(int),
2413 .proc_handler = proc_dointvec,
2416 .procname = "redirect_number",
2417 .data = &ip_rt_redirect_number,
2418 .maxlen = sizeof(int),
2420 .proc_handler = proc_dointvec,
2423 .procname = "redirect_silence",
2424 .data = &ip_rt_redirect_silence,
2425 .maxlen = sizeof(int),
2427 .proc_handler = proc_dointvec,
2430 .procname = "error_cost",
2431 .data = &ip_rt_error_cost,
2432 .maxlen = sizeof(int),
2434 .proc_handler = proc_dointvec,
2437 .procname = "error_burst",
2438 .data = &ip_rt_error_burst,
2439 .maxlen = sizeof(int),
2441 .proc_handler = proc_dointvec,
2444 .procname = "gc_elasticity",
2445 .data = &ip_rt_gc_elasticity,
2446 .maxlen = sizeof(int),
2448 .proc_handler = proc_dointvec,
2451 .procname = "mtu_expires",
2452 .data = &ip_rt_mtu_expires,
2453 .maxlen = sizeof(int),
2455 .proc_handler = proc_dointvec_jiffies,
2458 .procname = "min_pmtu",
2459 .data = &ip_rt_min_pmtu,
2460 .maxlen = sizeof(int),
2462 .proc_handler = proc_dointvec,
2465 .procname = "min_adv_mss",
2466 .data = &ip_rt_min_advmss,
2467 .maxlen = sizeof(int),
2469 .proc_handler = proc_dointvec,
2474 static struct ctl_table ipv4_route_flush_table[] = {
2476 .procname = "flush",
2477 .maxlen = sizeof(int),
2479 .proc_handler = ipv4_sysctl_rtcache_flush,
2484 static __net_init int sysctl_route_net_init(struct net *net)
2486 struct ctl_table *tbl;
2488 tbl = ipv4_route_flush_table;
2489 if (!net_eq(net, &init_net)) {
2490 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
2494 tbl[0].extra1 = net;
2496 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
2497 if (net->ipv4.route_hdr == NULL)
2502 if (tbl != ipv4_route_flush_table)
2508 static __net_exit void sysctl_route_net_exit(struct net *net)
2510 struct ctl_table *tbl;
2512 tbl = net->ipv4.route_hdr->ctl_table_arg;
2513 unregister_net_sysctl_table(net->ipv4.route_hdr);
2514 BUG_ON(tbl == ipv4_route_flush_table);
2518 static __net_initdata struct pernet_operations sysctl_route_ops = {
2519 .init = sysctl_route_net_init,
2520 .exit = sysctl_route_net_exit,
2524 static __net_init int rt_genid_init(struct net *net)
2526 atomic_set(&net->rt_genid, 0);
2527 get_random_bytes(&net->ipv4.dev_addr_genid,
2528 sizeof(net->ipv4.dev_addr_genid));
2532 static __net_initdata struct pernet_operations rt_genid_ops = {
2533 .init = rt_genid_init,
2536 static int __net_init ipv4_inetpeer_init(struct net *net)
2538 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
2542 inet_peer_base_init(bp);
2543 net->ipv4.peers = bp;
2547 static void __net_exit ipv4_inetpeer_exit(struct net *net)
2549 struct inet_peer_base *bp = net->ipv4.peers;
2551 net->ipv4.peers = NULL;
2552 inetpeer_invalidate_tree(bp);
2556 static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
2557 .init = ipv4_inetpeer_init,
2558 .exit = ipv4_inetpeer_exit,
2561 #ifdef CONFIG_IP_ROUTE_CLASSID
2562 struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
2563 #endif /* CONFIG_IP_ROUTE_CLASSID */
2565 int __init ip_rt_init(void)
2569 #ifdef CONFIG_IP_ROUTE_CLASSID
2570 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
2572 panic("IP: failed to allocate ip_rt_acct\n");
2575 ipv4_dst_ops.kmem_cachep =
2576 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
2577 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
2579 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
2581 if (dst_entries_init(&ipv4_dst_ops) < 0)
2582 panic("IP: failed to allocate ipv4_dst_ops counter\n");
2584 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
2585 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
2587 ipv4_dst_ops.gc_thresh = ~0;
2588 ip_rt_max_size = INT_MAX;
2593 if (ip_rt_proc_init())
2594 pr_err("Unable to create route proc files\n");
2597 xfrm4_init(ip_rt_max_size);
2599 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL);
2601 #ifdef CONFIG_SYSCTL
2602 register_pernet_subsys(&sysctl_route_ops);
2604 register_pernet_subsys(&rt_genid_ops);
2605 register_pernet_subsys(&ipv4_inetpeer_ops);
2609 #ifdef CONFIG_SYSCTL
2611 * We really need to sanitize the damn ipv4 init order, then all
2612 * this nonsense will go away.
2614 void __init ip_static_sysctl_init(void)
2616 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);