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 <linux/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>
92 #include <linux/jhash.h>
94 #include <net/dst_metadata.h>
95 #include <net/net_namespace.h>
96 #include <net/protocol.h>
98 #include <net/route.h>
99 #include <net/inetpeer.h>
100 #include <net/sock.h>
101 #include <net/ip_fib.h>
104 #include <net/icmp.h>
105 #include <net/xfrm.h>
106 #include <net/lwtunnel.h>
107 #include <net/netevent.h>
108 #include <net/rtnetlink.h>
110 #include <linux/sysctl.h>
112 #include <net/secure_seq.h>
113 #include <net/ip_tunnels.h>
114 #include <net/l3mdev.h>
116 #include "fib_lookup.h"
118 #define RT_FL_TOS(oldflp4) \
119 ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
121 #define RT_GC_TIMEOUT (300*HZ)
123 static int ip_rt_max_size;
124 static int ip_rt_redirect_number __read_mostly = 9;
125 static int ip_rt_redirect_load __read_mostly = HZ / 50;
126 static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
127 static int ip_rt_error_cost __read_mostly = HZ;
128 static int ip_rt_error_burst __read_mostly = 5 * HZ;
129 static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
130 static u32 ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
131 static int ip_rt_min_advmss __read_mostly = 256;
133 static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
136 * Interface to generic destination cache.
139 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
140 static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
141 static unsigned int ipv4_mtu(const struct dst_entry *dst);
142 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
143 static void ipv4_link_failure(struct sk_buff *skb);
144 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
145 struct sk_buff *skb, u32 mtu);
146 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk,
147 struct sk_buff *skb);
148 static void ipv4_dst_destroy(struct dst_entry *dst);
150 static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
156 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
159 static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr);
161 static struct dst_ops ipv4_dst_ops = {
163 .check = ipv4_dst_check,
164 .default_advmss = ipv4_default_advmss,
166 .cow_metrics = ipv4_cow_metrics,
167 .destroy = ipv4_dst_destroy,
168 .negative_advice = ipv4_negative_advice,
169 .link_failure = ipv4_link_failure,
170 .update_pmtu = ip_rt_update_pmtu,
171 .redirect = ip_do_redirect,
172 .local_out = __ip_local_out,
173 .neigh_lookup = ipv4_neigh_lookup,
174 .confirm_neigh = ipv4_confirm_neigh,
177 #define ECN_OR_COST(class) TC_PRIO_##class
179 const __u8 ip_tos2prio[16] = {
181 ECN_OR_COST(BESTEFFORT),
183 ECN_OR_COST(BESTEFFORT),
189 ECN_OR_COST(INTERACTIVE),
191 ECN_OR_COST(INTERACTIVE),
192 TC_PRIO_INTERACTIVE_BULK,
193 ECN_OR_COST(INTERACTIVE_BULK),
194 TC_PRIO_INTERACTIVE_BULK,
195 ECN_OR_COST(INTERACTIVE_BULK)
197 EXPORT_SYMBOL(ip_tos2prio);
199 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
200 #define RT_CACHE_STAT_INC(field) raw_cpu_inc(rt_cache_stat.field)
202 #ifdef CONFIG_PROC_FS
203 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
207 return SEQ_START_TOKEN;
210 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
216 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
220 static int rt_cache_seq_show(struct seq_file *seq, void *v)
222 if (v == SEQ_START_TOKEN)
223 seq_printf(seq, "%-127s\n",
224 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
225 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
230 static const struct seq_operations rt_cache_seq_ops = {
231 .start = rt_cache_seq_start,
232 .next = rt_cache_seq_next,
233 .stop = rt_cache_seq_stop,
234 .show = rt_cache_seq_show,
237 static int rt_cache_seq_open(struct inode *inode, struct file *file)
239 return seq_open(file, &rt_cache_seq_ops);
242 static const struct file_operations rt_cache_seq_fops = {
243 .open = rt_cache_seq_open,
246 .release = seq_release,
250 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
255 return SEQ_START_TOKEN;
257 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
258 if (!cpu_possible(cpu))
261 return &per_cpu(rt_cache_stat, cpu);
266 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
270 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
271 if (!cpu_possible(cpu))
274 return &per_cpu(rt_cache_stat, cpu);
280 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
285 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
287 struct rt_cache_stat *st = v;
289 if (v == SEQ_START_TOKEN) {
290 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");
294 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
295 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
296 dst_entries_get_slow(&ipv4_dst_ops),
309 0, /* st->gc_total */
310 0, /* st->gc_ignored */
311 0, /* st->gc_goal_miss */
312 0, /* st->gc_dst_overflow */
313 0, /* st->in_hlist_search */
314 0 /* st->out_hlist_search */
319 static const struct seq_operations rt_cpu_seq_ops = {
320 .start = rt_cpu_seq_start,
321 .next = rt_cpu_seq_next,
322 .stop = rt_cpu_seq_stop,
323 .show = rt_cpu_seq_show,
327 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
329 return seq_open(file, &rt_cpu_seq_ops);
332 static const struct file_operations rt_cpu_seq_fops = {
333 .open = rt_cpu_seq_open,
336 .release = seq_release,
339 #ifdef CONFIG_IP_ROUTE_CLASSID
340 static int rt_acct_proc_show(struct seq_file *m, void *v)
342 struct ip_rt_acct *dst, *src;
345 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
349 for_each_possible_cpu(i) {
350 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
351 for (j = 0; j < 256; j++) {
352 dst[j].o_bytes += src[j].o_bytes;
353 dst[j].o_packets += src[j].o_packets;
354 dst[j].i_bytes += src[j].i_bytes;
355 dst[j].i_packets += src[j].i_packets;
359 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
365 static int __net_init ip_rt_do_proc_init(struct net *net)
367 struct proc_dir_entry *pde;
369 pde = proc_create("rt_cache", 0444, net->proc_net,
374 pde = proc_create("rt_cache", 0444,
375 net->proc_net_stat, &rt_cpu_seq_fops);
379 #ifdef CONFIG_IP_ROUTE_CLASSID
380 pde = proc_create_single("rt_acct", 0, net->proc_net,
387 #ifdef CONFIG_IP_ROUTE_CLASSID
389 remove_proc_entry("rt_cache", net->proc_net_stat);
392 remove_proc_entry("rt_cache", net->proc_net);
397 static void __net_exit ip_rt_do_proc_exit(struct net *net)
399 remove_proc_entry("rt_cache", net->proc_net_stat);
400 remove_proc_entry("rt_cache", net->proc_net);
401 #ifdef CONFIG_IP_ROUTE_CLASSID
402 remove_proc_entry("rt_acct", net->proc_net);
406 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
407 .init = ip_rt_do_proc_init,
408 .exit = ip_rt_do_proc_exit,
411 static int __init ip_rt_proc_init(void)
413 return register_pernet_subsys(&ip_rt_proc_ops);
417 static inline int ip_rt_proc_init(void)
421 #endif /* CONFIG_PROC_FS */
423 static inline bool rt_is_expired(const struct rtable *rth)
425 return rth->rt_genid != rt_genid_ipv4(dev_net(rth->dst.dev));
428 void rt_cache_flush(struct net *net)
430 rt_genid_bump_ipv4(net);
433 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
437 struct net_device *dev = dst->dev;
438 const __be32 *pkey = daddr;
439 const struct rtable *rt;
442 rt = (const struct rtable *) dst;
444 pkey = (const __be32 *) &rt->rt_gateway;
446 pkey = &ip_hdr(skb)->daddr;
448 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
451 return neigh_create(&arp_tbl, pkey, dev);
454 static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr)
456 struct net_device *dev = dst->dev;
457 const __be32 *pkey = daddr;
458 const struct rtable *rt;
460 rt = (const struct rtable *)dst;
462 pkey = (const __be32 *)&rt->rt_gateway;
465 (RTCF_MULTICAST | RTCF_BROADCAST | RTCF_LOCAL)))
468 __ipv4_confirm_neigh(dev, *(__force u32 *)pkey);
471 #define IP_IDENTS_SZ 2048u
473 static atomic_t *ip_idents __read_mostly;
474 static u32 *ip_tstamps __read_mostly;
476 /* In order to protect privacy, we add a perturbation to identifiers
477 * if one generator is seldom used. This makes hard for an attacker
478 * to infer how many packets were sent between two points in time.
480 u32 ip_idents_reserve(u32 hash, int segs)
482 u32 *p_tstamp = ip_tstamps + hash % IP_IDENTS_SZ;
483 atomic_t *p_id = ip_idents + hash % IP_IDENTS_SZ;
484 u32 old = READ_ONCE(*p_tstamp);
485 u32 now = (u32)jiffies;
488 if (old != now && cmpxchg(p_tstamp, old, now) == old)
489 delta = prandom_u32_max(now - old);
491 /* Do not use atomic_add_return() as it makes UBSAN unhappy */
493 old = (u32)atomic_read(p_id);
494 new = old + delta + segs;
495 } while (atomic_cmpxchg(p_id, old, new) != old);
499 EXPORT_SYMBOL(ip_idents_reserve);
501 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs)
503 static u32 ip_idents_hashrnd __read_mostly;
506 net_get_random_once(&ip_idents_hashrnd, sizeof(ip_idents_hashrnd));
508 hash = jhash_3words((__force u32)iph->daddr,
509 (__force u32)iph->saddr,
510 iph->protocol ^ net_hash_mix(net),
512 id = ip_idents_reserve(hash, segs);
515 EXPORT_SYMBOL(__ip_select_ident);
517 static void __build_flow_key(const struct net *net, struct flowi4 *fl4,
518 const struct sock *sk,
519 const struct iphdr *iph,
521 u8 prot, u32 mark, int flow_flags)
524 const struct inet_sock *inet = inet_sk(sk);
526 oif = sk->sk_bound_dev_if;
528 tos = RT_CONN_FLAGS(sk);
529 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
531 flowi4_init_output(fl4, oif, mark, tos,
532 RT_SCOPE_UNIVERSE, prot,
534 iph->daddr, iph->saddr, 0, 0,
535 sock_net_uid(net, sk));
538 static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
539 const struct sock *sk)
541 const struct net *net = dev_net(skb->dev);
542 const struct iphdr *iph = ip_hdr(skb);
543 int oif = skb->dev->ifindex;
544 u8 tos = RT_TOS(iph->tos);
545 u8 prot = iph->protocol;
546 u32 mark = skb->mark;
548 __build_flow_key(net, fl4, sk, iph, oif, tos, prot, mark, 0);
551 static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
553 const struct inet_sock *inet = inet_sk(sk);
554 const struct ip_options_rcu *inet_opt;
555 __be32 daddr = inet->inet_daddr;
558 inet_opt = rcu_dereference(inet->inet_opt);
559 if (inet_opt && inet_opt->opt.srr)
560 daddr = inet_opt->opt.faddr;
561 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
562 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
563 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
564 inet_sk_flowi_flags(sk),
565 daddr, inet->inet_saddr, 0, 0, sk->sk_uid);
569 static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
570 const struct sk_buff *skb)
573 build_skb_flow_key(fl4, skb, sk);
575 build_sk_flow_key(fl4, sk);
578 static DEFINE_SPINLOCK(fnhe_lock);
580 static void fnhe_flush_routes(struct fib_nh_exception *fnhe)
584 rt = rcu_dereference(fnhe->fnhe_rth_input);
586 RCU_INIT_POINTER(fnhe->fnhe_rth_input, NULL);
587 dst_dev_put(&rt->dst);
588 dst_release(&rt->dst);
590 rt = rcu_dereference(fnhe->fnhe_rth_output);
592 RCU_INIT_POINTER(fnhe->fnhe_rth_output, NULL);
593 dst_dev_put(&rt->dst);
594 dst_release(&rt->dst);
598 static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
600 struct fib_nh_exception *fnhe, *oldest;
602 oldest = rcu_dereference(hash->chain);
603 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
604 fnhe = rcu_dereference(fnhe->fnhe_next)) {
605 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
608 fnhe_flush_routes(oldest);
612 static inline u32 fnhe_hashfun(__be32 daddr)
614 static u32 fnhe_hashrnd __read_mostly;
617 net_get_random_once(&fnhe_hashrnd, sizeof(fnhe_hashrnd));
618 hval = jhash_1word((__force u32) daddr, fnhe_hashrnd);
619 return hash_32(hval, FNHE_HASH_SHIFT);
622 static void fill_route_from_fnhe(struct rtable *rt, struct fib_nh_exception *fnhe)
624 rt->rt_pmtu = fnhe->fnhe_pmtu;
625 rt->rt_mtu_locked = fnhe->fnhe_mtu_locked;
626 rt->dst.expires = fnhe->fnhe_expires;
629 rt->rt_flags |= RTCF_REDIRECTED;
630 rt->rt_gateway = fnhe->fnhe_gw;
631 rt->rt_uses_gateway = 1;
635 static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
636 u32 pmtu, bool lock, unsigned long expires)
638 struct fnhe_hash_bucket *hash;
639 struct fib_nh_exception *fnhe;
645 genid = fnhe_genid(dev_net(nh->nh_dev));
646 hval = fnhe_hashfun(daddr);
648 spin_lock_bh(&fnhe_lock);
650 hash = rcu_dereference(nh->nh_exceptions);
652 hash = kcalloc(FNHE_HASH_SIZE, sizeof(*hash), GFP_ATOMIC);
655 rcu_assign_pointer(nh->nh_exceptions, hash);
661 for (fnhe = rcu_dereference(hash->chain); fnhe;
662 fnhe = rcu_dereference(fnhe->fnhe_next)) {
663 if (fnhe->fnhe_daddr == daddr)
669 if (fnhe->fnhe_genid != genid)
670 fnhe->fnhe_genid = genid;
674 fnhe->fnhe_pmtu = pmtu;
675 fnhe->fnhe_mtu_locked = lock;
677 fnhe->fnhe_expires = max(1UL, expires);
678 /* Update all cached dsts too */
679 rt = rcu_dereference(fnhe->fnhe_rth_input);
681 fill_route_from_fnhe(rt, fnhe);
682 rt = rcu_dereference(fnhe->fnhe_rth_output);
684 fill_route_from_fnhe(rt, fnhe);
686 if (depth > FNHE_RECLAIM_DEPTH)
687 fnhe = fnhe_oldest(hash);
689 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
693 fnhe->fnhe_next = hash->chain;
694 rcu_assign_pointer(hash->chain, fnhe);
696 fnhe->fnhe_genid = genid;
697 fnhe->fnhe_daddr = daddr;
699 fnhe->fnhe_pmtu = pmtu;
700 fnhe->fnhe_mtu_locked = lock;
701 fnhe->fnhe_expires = max(1UL, expires);
703 /* Exception created; mark the cached routes for the nexthop
704 * stale, so anyone caching it rechecks if this exception
707 rt = rcu_dereference(nh->nh_rth_input);
709 rt->dst.obsolete = DST_OBSOLETE_KILL;
711 for_each_possible_cpu(i) {
712 struct rtable __rcu **prt;
713 prt = per_cpu_ptr(nh->nh_pcpu_rth_output, i);
714 rt = rcu_dereference(*prt);
716 rt->dst.obsolete = DST_OBSOLETE_KILL;
720 fnhe->fnhe_stamp = jiffies;
723 spin_unlock_bh(&fnhe_lock);
726 static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4,
729 __be32 new_gw = icmp_hdr(skb)->un.gateway;
730 __be32 old_gw = ip_hdr(skb)->saddr;
731 struct net_device *dev = skb->dev;
732 struct in_device *in_dev;
733 struct fib_result res;
737 switch (icmp_hdr(skb)->code & 7) {
739 case ICMP_REDIR_NETTOS:
740 case ICMP_REDIR_HOST:
741 case ICMP_REDIR_HOSTTOS:
748 if (rt->rt_gateway != old_gw)
751 in_dev = __in_dev_get_rcu(dev);
756 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
757 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
758 ipv4_is_zeronet(new_gw))
759 goto reject_redirect;
761 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
762 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
763 goto reject_redirect;
764 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
765 goto reject_redirect;
767 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
768 goto reject_redirect;
771 n = __ipv4_neigh_lookup(rt->dst.dev, new_gw);
773 n = neigh_create(&arp_tbl, &new_gw, rt->dst.dev);
775 if (!(n->nud_state & NUD_VALID)) {
776 neigh_event_send(n, NULL);
778 if (fib_lookup(net, fl4, &res, 0) == 0) {
779 struct fib_nh *nh = &FIB_RES_NH(res);
781 update_or_create_fnhe(nh, fl4->daddr, new_gw,
783 jiffies + ip_rt_gc_timeout);
786 rt->dst.obsolete = DST_OBSOLETE_KILL;
787 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
794 #ifdef CONFIG_IP_ROUTE_VERBOSE
795 if (IN_DEV_LOG_MARTIANS(in_dev)) {
796 const struct iphdr *iph = (const struct iphdr *) skb->data;
797 __be32 daddr = iph->daddr;
798 __be32 saddr = iph->saddr;
800 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
801 " Advised path = %pI4 -> %pI4\n",
802 &old_gw, dev->name, &new_gw,
809 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
813 const struct iphdr *iph = (const struct iphdr *) skb->data;
814 struct net *net = dev_net(skb->dev);
815 int oif = skb->dev->ifindex;
816 u8 tos = RT_TOS(iph->tos);
817 u8 prot = iph->protocol;
818 u32 mark = skb->mark;
820 rt = (struct rtable *) dst;
822 __build_flow_key(net, &fl4, sk, iph, oif, tos, prot, mark, 0);
823 __ip_do_redirect(rt, skb, &fl4, true);
826 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
828 struct rtable *rt = (struct rtable *)dst;
829 struct dst_entry *ret = dst;
832 if (dst->obsolete > 0) {
835 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
846 * 1. The first ip_rt_redirect_number redirects are sent
847 * with exponential backoff, then we stop sending them at all,
848 * assuming that the host ignores our redirects.
849 * 2. If we did not see packets requiring redirects
850 * during ip_rt_redirect_silence, we assume that the host
851 * forgot redirected route and start to send redirects again.
853 * This algorithm is much cheaper and more intelligent than dumb load limiting
856 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
857 * and "frag. need" (breaks PMTU discovery) in icmp.c.
860 void ip_rt_send_redirect(struct sk_buff *skb)
862 struct rtable *rt = skb_rtable(skb);
863 struct in_device *in_dev;
864 struct inet_peer *peer;
870 in_dev = __in_dev_get_rcu(rt->dst.dev);
871 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
875 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
876 vif = l3mdev_master_ifindex_rcu(rt->dst.dev);
879 net = dev_net(rt->dst.dev);
880 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, vif, 1);
882 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST,
883 rt_nexthop(rt, ip_hdr(skb)->daddr));
887 /* No redirected packets during ip_rt_redirect_silence;
888 * reset the algorithm.
890 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence)) {
891 peer->rate_tokens = 0;
892 peer->n_redirects = 0;
895 /* Too many ignored redirects; do not send anything
896 * set dst.rate_last to the last seen redirected packet.
898 if (peer->n_redirects >= ip_rt_redirect_number) {
899 peer->rate_last = jiffies;
903 /* Check for load limit; set rate_last to the latest sent
906 if (peer->rate_tokens == 0 ||
909 (ip_rt_redirect_load << peer->rate_tokens)))) {
910 __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr);
912 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw);
913 peer->rate_last = jiffies;
916 #ifdef CONFIG_IP_ROUTE_VERBOSE
918 peer->rate_tokens == ip_rt_redirect_number)
919 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
920 &ip_hdr(skb)->saddr, inet_iif(skb),
921 &ip_hdr(skb)->daddr, &gw);
928 static int ip_error(struct sk_buff *skb)
930 struct rtable *rt = skb_rtable(skb);
931 struct net_device *dev = skb->dev;
932 struct in_device *in_dev;
933 struct inet_peer *peer;
939 if (netif_is_l3_master(skb->dev)) {
940 dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif);
945 in_dev = __in_dev_get_rcu(dev);
947 /* IP on this device is disabled. */
951 net = dev_net(rt->dst.dev);
952 if (!IN_DEV_FORWARD(in_dev)) {
953 switch (rt->dst.error) {
955 __IP_INC_STATS(net, IPSTATS_MIB_INADDRERRORS);
959 __IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES);
965 switch (rt->dst.error) {
970 code = ICMP_HOST_UNREACH;
973 code = ICMP_NET_UNREACH;
974 __IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES);
977 code = ICMP_PKT_FILTERED;
981 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr,
982 l3mdev_master_ifindex(skb->dev), 1);
987 peer->rate_tokens += now - peer->rate_last;
988 if (peer->rate_tokens > ip_rt_error_burst)
989 peer->rate_tokens = ip_rt_error_burst;
990 peer->rate_last = now;
991 if (peer->rate_tokens >= ip_rt_error_cost)
992 peer->rate_tokens -= ip_rt_error_cost;
998 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
1000 out: kfree_skb(skb);
1004 static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
1006 struct dst_entry *dst = &rt->dst;
1007 u32 old_mtu = ipv4_mtu(dst);
1008 struct fib_result res;
1011 if (ip_mtu_locked(dst))
1017 if (mtu < ip_rt_min_pmtu) {
1019 mtu = min(old_mtu, ip_rt_min_pmtu);
1022 if (rt->rt_pmtu == mtu && !lock &&
1023 time_before(jiffies, dst->expires - ip_rt_mtu_expires / 2))
1027 if (fib_lookup(dev_net(dst->dev), fl4, &res, 0) == 0) {
1028 struct fib_nh *nh = &FIB_RES_NH(res);
1030 update_or_create_fnhe(nh, fl4->daddr, 0, mtu, lock,
1031 jiffies + ip_rt_mtu_expires);
1036 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1037 struct sk_buff *skb, u32 mtu)
1039 struct rtable *rt = (struct rtable *) dst;
1042 ip_rt_build_flow_key(&fl4, sk, skb);
1043 __ip_rt_update_pmtu(rt, &fl4, mtu);
1046 void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
1047 int oif, u8 protocol)
1049 const struct iphdr *iph = (const struct iphdr *) skb->data;
1052 u32 mark = IP4_REPLY_MARK(net, skb->mark);
1054 __build_flow_key(net, &fl4, NULL, iph, oif,
1055 RT_TOS(iph->tos), protocol, mark, 0);
1056 rt = __ip_route_output_key(net, &fl4);
1058 __ip_rt_update_pmtu(rt, &fl4, mtu);
1062 EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
1064 static void __ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
1066 const struct iphdr *iph = (const struct iphdr *) skb->data;
1070 __build_flow_key(sock_net(sk), &fl4, sk, iph, 0, 0, 0, 0, 0);
1072 if (!fl4.flowi4_mark)
1073 fl4.flowi4_mark = IP4_REPLY_MARK(sock_net(sk), skb->mark);
1075 rt = __ip_route_output_key(sock_net(sk), &fl4);
1077 __ip_rt_update_pmtu(rt, &fl4, mtu);
1082 void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
1084 const struct iphdr *iph = (const struct iphdr *) skb->data;
1087 struct dst_entry *odst = NULL;
1089 struct net *net = sock_net(sk);
1093 if (!ip_sk_accept_pmtu(sk))
1096 odst = sk_dst_get(sk);
1098 if (sock_owned_by_user(sk) || !odst) {
1099 __ipv4_sk_update_pmtu(skb, sk, mtu);
1103 __build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0);
1105 rt = (struct rtable *)odst;
1106 if (odst->obsolete && !odst->ops->check(odst, 0)) {
1107 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
1114 __ip_rt_update_pmtu((struct rtable *) xfrm_dst_path(&rt->dst), &fl4, mtu);
1116 if (!dst_check(&rt->dst, 0)) {
1118 dst_release(&rt->dst);
1120 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
1128 sk_dst_set(sk, &rt->dst);
1134 EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
1136 void ipv4_redirect(struct sk_buff *skb, struct net *net,
1137 int oif, u8 protocol)
1139 const struct iphdr *iph = (const struct iphdr *) skb->data;
1143 __build_flow_key(net, &fl4, NULL, iph, oif,
1144 RT_TOS(iph->tos), protocol, 0, 0);
1145 rt = __ip_route_output_key(net, &fl4);
1147 __ip_do_redirect(rt, skb, &fl4, false);
1151 EXPORT_SYMBOL_GPL(ipv4_redirect);
1153 void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
1155 const struct iphdr *iph = (const struct iphdr *) skb->data;
1158 struct net *net = sock_net(sk);
1160 __build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0);
1161 rt = __ip_route_output_key(net, &fl4);
1163 __ip_do_redirect(rt, skb, &fl4, false);
1167 EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1169 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1171 struct rtable *rt = (struct rtable *) dst;
1173 /* All IPV4 dsts are created with ->obsolete set to the value
1174 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1175 * into this function always.
1177 * When a PMTU/redirect information update invalidates a route,
1178 * this is indicated by setting obsolete to DST_OBSOLETE_KILL or
1179 * DST_OBSOLETE_DEAD by dst_free().
1181 if (dst->obsolete != DST_OBSOLETE_FORCE_CHK || rt_is_expired(rt))
1186 static void ipv4_link_failure(struct sk_buff *skb)
1190 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1192 rt = skb_rtable(skb);
1194 dst_set_expires(&rt->dst, 0);
1197 static int ip_rt_bug(struct net *net, struct sock *sk, struct sk_buff *skb)
1199 pr_debug("%s: %pI4 -> %pI4, %s\n",
1200 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1201 skb->dev ? skb->dev->name : "?");
1208 We do not cache source address of outgoing interface,
1209 because it is used only by IP RR, TS and SRR options,
1210 so that it out of fast path.
1212 BTW remember: "addr" is allowed to be not aligned
1216 void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
1220 if (rt_is_output_route(rt))
1221 src = ip_hdr(skb)->saddr;
1223 struct fib_result res;
1224 struct iphdr *iph = ip_hdr(skb);
1225 struct flowi4 fl4 = {
1226 .daddr = iph->daddr,
1227 .saddr = iph->saddr,
1228 .flowi4_tos = RT_TOS(iph->tos),
1229 .flowi4_oif = rt->dst.dev->ifindex,
1230 .flowi4_iif = skb->dev->ifindex,
1231 .flowi4_mark = skb->mark,
1235 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0)
1236 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
1238 src = inet_select_addr(rt->dst.dev,
1239 rt_nexthop(rt, iph->daddr),
1243 memcpy(addr, &src, 4);
1246 #ifdef CONFIG_IP_ROUTE_CLASSID
1247 static void set_class_tag(struct rtable *rt, u32 tag)
1249 if (!(rt->dst.tclassid & 0xFFFF))
1250 rt->dst.tclassid |= tag & 0xFFFF;
1251 if (!(rt->dst.tclassid & 0xFFFF0000))
1252 rt->dst.tclassid |= tag & 0xFFFF0000;
1256 static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1258 unsigned int header_size = sizeof(struct tcphdr) + sizeof(struct iphdr);
1259 unsigned int advmss = max_t(unsigned int, ipv4_mtu(dst) - header_size,
1262 return min(advmss, IPV4_MAX_PMTU - header_size);
1265 static unsigned int ipv4_mtu(const struct dst_entry *dst)
1267 const struct rtable *rt = (const struct rtable *) dst;
1268 unsigned int mtu = rt->rt_pmtu;
1270 if (!mtu || time_after_eq(jiffies, rt->dst.expires))
1271 mtu = dst_metric_raw(dst, RTAX_MTU);
1276 mtu = READ_ONCE(dst->dev->mtu);
1278 if (unlikely(ip_mtu_locked(dst))) {
1279 if (rt->rt_uses_gateway && mtu > 576)
1283 mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
1285 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
1288 static void ip_del_fnhe(struct fib_nh *nh, __be32 daddr)
1290 struct fnhe_hash_bucket *hash;
1291 struct fib_nh_exception *fnhe, __rcu **fnhe_p;
1292 u32 hval = fnhe_hashfun(daddr);
1294 spin_lock_bh(&fnhe_lock);
1296 hash = rcu_dereference_protected(nh->nh_exceptions,
1297 lockdep_is_held(&fnhe_lock));
1300 fnhe_p = &hash->chain;
1301 fnhe = rcu_dereference_protected(*fnhe_p, lockdep_is_held(&fnhe_lock));
1303 if (fnhe->fnhe_daddr == daddr) {
1304 rcu_assign_pointer(*fnhe_p, rcu_dereference_protected(
1305 fnhe->fnhe_next, lockdep_is_held(&fnhe_lock)));
1306 fnhe_flush_routes(fnhe);
1307 kfree_rcu(fnhe, rcu);
1310 fnhe_p = &fnhe->fnhe_next;
1311 fnhe = rcu_dereference_protected(fnhe->fnhe_next,
1312 lockdep_is_held(&fnhe_lock));
1315 spin_unlock_bh(&fnhe_lock);
1318 static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
1320 struct fnhe_hash_bucket *hash = rcu_dereference(nh->nh_exceptions);
1321 struct fib_nh_exception *fnhe;
1327 hval = fnhe_hashfun(daddr);
1329 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1330 fnhe = rcu_dereference(fnhe->fnhe_next)) {
1331 if (fnhe->fnhe_daddr == daddr) {
1332 if (fnhe->fnhe_expires &&
1333 time_after(jiffies, fnhe->fnhe_expires)) {
1334 ip_del_fnhe(nh, daddr);
1344 * 1. mtu on route is locked - use it
1345 * 2. mtu from nexthop exception
1346 * 3. mtu from egress device
1349 u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr)
1351 struct fib_info *fi = res->fi;
1352 struct fib_nh *nh = &fi->fib_nh[res->nh_sel];
1353 struct net_device *dev = nh->nh_dev;
1356 if (dev_net(dev)->ipv4.sysctl_ip_fwd_use_pmtu ||
1357 fi->fib_metrics->metrics[RTAX_LOCK - 1] & (1 << RTAX_MTU))
1361 struct fib_nh_exception *fnhe;
1363 fnhe = find_exception(nh, daddr);
1364 if (fnhe && !time_after_eq(jiffies, fnhe->fnhe_expires))
1365 mtu = fnhe->fnhe_pmtu;
1369 mtu = min(READ_ONCE(dev->mtu), IP_MAX_MTU);
1371 return mtu - lwtunnel_headroom(nh->nh_lwtstate, mtu);
1374 static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
1375 __be32 daddr, const bool do_cache)
1379 spin_lock_bh(&fnhe_lock);
1381 if (daddr == fnhe->fnhe_daddr) {
1382 struct rtable __rcu **porig;
1383 struct rtable *orig;
1384 int genid = fnhe_genid(dev_net(rt->dst.dev));
1386 if (rt_is_input_route(rt))
1387 porig = &fnhe->fnhe_rth_input;
1389 porig = &fnhe->fnhe_rth_output;
1390 orig = rcu_dereference(*porig);
1392 if (fnhe->fnhe_genid != genid) {
1393 fnhe->fnhe_genid = genid;
1395 fnhe->fnhe_pmtu = 0;
1396 fnhe->fnhe_expires = 0;
1397 fnhe->fnhe_mtu_locked = false;
1398 fnhe_flush_routes(fnhe);
1401 fill_route_from_fnhe(rt, fnhe);
1402 if (!rt->rt_gateway)
1403 rt->rt_gateway = daddr;
1407 rcu_assign_pointer(*porig, rt);
1409 dst_dev_put(&orig->dst);
1410 dst_release(&orig->dst);
1415 fnhe->fnhe_stamp = jiffies;
1417 spin_unlock_bh(&fnhe_lock);
1422 static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt)
1424 struct rtable *orig, *prev, **p;
1427 if (rt_is_input_route(rt)) {
1428 p = (struct rtable **)&nh->nh_rth_input;
1430 p = (struct rtable **)raw_cpu_ptr(nh->nh_pcpu_rth_output);
1434 /* hold dst before doing cmpxchg() to avoid race condition
1438 prev = cmpxchg(p, orig, rt);
1441 dst_dev_put(&orig->dst);
1442 dst_release(&orig->dst);
1445 dst_release(&rt->dst);
1452 struct uncached_list {
1454 struct list_head head;
1457 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt_uncached_list);
1459 void rt_add_uncached_list(struct rtable *rt)
1461 struct uncached_list *ul = raw_cpu_ptr(&rt_uncached_list);
1463 rt->rt_uncached_list = ul;
1465 spin_lock_bh(&ul->lock);
1466 list_add_tail(&rt->rt_uncached, &ul->head);
1467 spin_unlock_bh(&ul->lock);
1470 void rt_del_uncached_list(struct rtable *rt)
1472 if (!list_empty(&rt->rt_uncached)) {
1473 struct uncached_list *ul = rt->rt_uncached_list;
1475 spin_lock_bh(&ul->lock);
1476 list_del(&rt->rt_uncached);
1477 spin_unlock_bh(&ul->lock);
1481 static void ipv4_dst_destroy(struct dst_entry *dst)
1483 struct rtable *rt = (struct rtable *)dst;
1485 ip_dst_metrics_put(dst);
1486 rt_del_uncached_list(rt);
1489 void rt_flush_dev(struct net_device *dev)
1491 struct net *net = dev_net(dev);
1495 for_each_possible_cpu(cpu) {
1496 struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
1498 spin_lock_bh(&ul->lock);
1499 list_for_each_entry(rt, &ul->head, rt_uncached) {
1500 if (rt->dst.dev != dev)
1502 rt->dst.dev = net->loopback_dev;
1503 dev_hold(rt->dst.dev);
1506 spin_unlock_bh(&ul->lock);
1510 static bool rt_cache_valid(const struct rtable *rt)
1513 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1517 static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
1518 const struct fib_result *res,
1519 struct fib_nh_exception *fnhe,
1520 struct fib_info *fi, u16 type, u32 itag,
1521 const bool do_cache)
1523 bool cached = false;
1526 struct fib_nh *nh = &FIB_RES_NH(*res);
1528 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) {
1529 rt->rt_gateway = nh->nh_gw;
1530 rt->rt_uses_gateway = 1;
1532 ip_dst_init_metrics(&rt->dst, fi->fib_metrics);
1534 #ifdef CONFIG_IP_ROUTE_CLASSID
1535 rt->dst.tclassid = nh->nh_tclassid;
1537 rt->dst.lwtstate = lwtstate_get(nh->nh_lwtstate);
1539 cached = rt_bind_exception(rt, fnhe, daddr, do_cache);
1541 cached = rt_cache_route(nh, rt);
1542 if (unlikely(!cached)) {
1543 /* Routes we intend to cache in nexthop exception or
1544 * FIB nexthop have the DST_NOCACHE bit clear.
1545 * However, if we are unsuccessful at storing this
1546 * route into the cache we really need to set it.
1548 if (!rt->rt_gateway)
1549 rt->rt_gateway = daddr;
1550 rt_add_uncached_list(rt);
1553 rt_add_uncached_list(rt);
1555 #ifdef CONFIG_IP_ROUTE_CLASSID
1556 #ifdef CONFIG_IP_MULTIPLE_TABLES
1557 set_class_tag(rt, res->tclassid);
1559 set_class_tag(rt, itag);
1563 struct rtable *rt_dst_alloc(struct net_device *dev,
1564 unsigned int flags, u16 type,
1565 bool nopolicy, bool noxfrm, bool will_cache)
1569 rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
1570 (will_cache ? 0 : DST_HOST) |
1571 (nopolicy ? DST_NOPOLICY : 0) |
1572 (noxfrm ? DST_NOXFRM : 0));
1575 rt->rt_genid = rt_genid_ipv4(dev_net(dev));
1576 rt->rt_flags = flags;
1578 rt->rt_is_input = 0;
1581 rt->rt_mtu_locked = 0;
1583 rt->rt_uses_gateway = 0;
1584 INIT_LIST_HEAD(&rt->rt_uncached);
1586 rt->dst.output = ip_output;
1587 if (flags & RTCF_LOCAL)
1588 rt->dst.input = ip_local_deliver;
1593 EXPORT_SYMBOL(rt_dst_alloc);
1595 /* called in rcu_read_lock() section */
1596 int ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1597 u8 tos, struct net_device *dev,
1598 struct in_device *in_dev, u32 *itag)
1602 /* Primary sanity checks. */
1606 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1607 skb->protocol != htons(ETH_P_IP))
1610 if (ipv4_is_loopback(saddr) && !IN_DEV_ROUTE_LOCALNET(in_dev))
1613 if (ipv4_is_zeronet(saddr)) {
1614 if (!ipv4_is_local_multicast(daddr) &&
1615 ip_hdr(skb)->protocol != IPPROTO_IGMP)
1618 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1626 /* called in rcu_read_lock() section */
1627 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1628 u8 tos, struct net_device *dev, int our)
1630 struct in_device *in_dev = __in_dev_get_rcu(dev);
1631 unsigned int flags = RTCF_MULTICAST;
1636 err = ip_mc_validate_source(skb, daddr, saddr, tos, dev, in_dev, &itag);
1641 flags |= RTCF_LOCAL;
1643 rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST,
1644 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false);
1648 #ifdef CONFIG_IP_ROUTE_CLASSID
1649 rth->dst.tclassid = itag;
1651 rth->dst.output = ip_rt_bug;
1652 rth->rt_is_input= 1;
1654 #ifdef CONFIG_IP_MROUTE
1655 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1656 rth->dst.input = ip_mr_input;
1658 RT_CACHE_STAT_INC(in_slow_mc);
1660 skb_dst_set(skb, &rth->dst);
1665 static void ip_handle_martian_source(struct net_device *dev,
1666 struct in_device *in_dev,
1667 struct sk_buff *skb,
1671 RT_CACHE_STAT_INC(in_martian_src);
1672 #ifdef CONFIG_IP_ROUTE_VERBOSE
1673 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1675 * RFC1812 recommendation, if source is martian,
1676 * the only hint is MAC header.
1678 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
1679 &daddr, &saddr, dev->name);
1680 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1681 print_hex_dump(KERN_WARNING, "ll header: ",
1682 DUMP_PREFIX_OFFSET, 16, 1,
1683 skb_mac_header(skb),
1684 dev->hard_header_len, false);
1690 /* called in rcu_read_lock() section */
1691 static int __mkroute_input(struct sk_buff *skb,
1692 const struct fib_result *res,
1693 struct in_device *in_dev,
1694 __be32 daddr, __be32 saddr, u32 tos)
1696 struct fib_nh_exception *fnhe;
1699 struct in_device *out_dev;
1703 /* get a working reference to the output device */
1704 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1706 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
1710 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
1711 in_dev->dev, in_dev, &itag);
1713 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1719 do_cache = res->fi && !itag;
1720 if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
1721 skb->protocol == htons(ETH_P_IP) &&
1722 (IN_DEV_SHARED_MEDIA(out_dev) ||
1723 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1724 IPCB(skb)->flags |= IPSKB_DOREDIRECT;
1726 if (skb->protocol != htons(ETH_P_IP)) {
1727 /* Not IP (i.e. ARP). Do not create route, if it is
1728 * invalid for proxy arp. DNAT routes are always valid.
1730 * Proxy arp feature have been extended to allow, ARP
1731 * replies back to the same interface, to support
1732 * Private VLAN switch technologies. See arp.c.
1734 if (out_dev == in_dev &&
1735 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1741 fnhe = find_exception(&FIB_RES_NH(*res), daddr);
1744 rth = rcu_dereference(fnhe->fnhe_rth_input);
1746 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1747 if (rt_cache_valid(rth)) {
1748 skb_dst_set_noref(skb, &rth->dst);
1753 rth = rt_dst_alloc(out_dev->dev, 0, res->type,
1754 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1755 IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache);
1761 rth->rt_is_input = 1;
1762 RT_CACHE_STAT_INC(in_slow_tot);
1764 rth->dst.input = ip_forward;
1766 rt_set_nexthop(rth, daddr, res, fnhe, res->fi, res->type, itag,
1768 lwtunnel_set_redirect(&rth->dst);
1769 skb_dst_set(skb, &rth->dst);
1776 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1777 /* To make ICMP packets follow the right flow, the multipath hash is
1778 * calculated from the inner IP addresses.
1780 static void ip_multipath_l3_keys(const struct sk_buff *skb,
1781 struct flow_keys *hash_keys)
1783 const struct iphdr *outer_iph = ip_hdr(skb);
1784 const struct iphdr *key_iph = outer_iph;
1785 const struct iphdr *inner_iph;
1786 const struct icmphdr *icmph;
1787 struct iphdr _inner_iph;
1788 struct icmphdr _icmph;
1790 if (likely(outer_iph->protocol != IPPROTO_ICMP))
1793 if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0))
1796 icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph),
1801 if (icmph->type != ICMP_DEST_UNREACH &&
1802 icmph->type != ICMP_REDIRECT &&
1803 icmph->type != ICMP_TIME_EXCEEDED &&
1804 icmph->type != ICMP_PARAMETERPROB)
1807 inner_iph = skb_header_pointer(skb,
1808 outer_iph->ihl * 4 + sizeof(_icmph),
1809 sizeof(_inner_iph), &_inner_iph);
1813 key_iph = inner_iph;
1815 hash_keys->addrs.v4addrs.src = key_iph->saddr;
1816 hash_keys->addrs.v4addrs.dst = key_iph->daddr;
1819 /* if skb is set it will be used and fl4 can be NULL */
1820 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
1821 const struct sk_buff *skb, struct flow_keys *flkeys)
1823 u32 multipath_hash = fl4 ? fl4->flowi4_multipath_hash : 0;
1824 struct flow_keys hash_keys;
1827 switch (net->ipv4.sysctl_fib_multipath_hash_policy) {
1829 memset(&hash_keys, 0, sizeof(hash_keys));
1830 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1832 ip_multipath_l3_keys(skb, &hash_keys);
1834 hash_keys.addrs.v4addrs.src = fl4->saddr;
1835 hash_keys.addrs.v4addrs.dst = fl4->daddr;
1839 /* skb is currently provided only when forwarding */
1841 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
1842 struct flow_keys keys;
1844 /* short-circuit if we already have L4 hash present */
1846 return skb_get_hash_raw(skb) >> 1;
1848 memset(&hash_keys, 0, sizeof(hash_keys));
1851 skb_flow_dissect_flow_keys(skb, &keys, flag);
1855 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1856 hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src;
1857 hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst;
1858 hash_keys.ports.src = flkeys->ports.src;
1859 hash_keys.ports.dst = flkeys->ports.dst;
1860 hash_keys.basic.ip_proto = flkeys->basic.ip_proto;
1862 memset(&hash_keys, 0, sizeof(hash_keys));
1863 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1864 hash_keys.addrs.v4addrs.src = fl4->saddr;
1865 hash_keys.addrs.v4addrs.dst = fl4->daddr;
1866 hash_keys.ports.src = fl4->fl4_sport;
1867 hash_keys.ports.dst = fl4->fl4_dport;
1868 hash_keys.basic.ip_proto = fl4->flowi4_proto;
1872 mhash = flow_hash_from_keys(&hash_keys);
1875 mhash = jhash_2words(mhash, multipath_hash, 0);
1879 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
1881 static int ip_mkroute_input(struct sk_buff *skb,
1882 struct fib_result *res,
1883 struct in_device *in_dev,
1884 __be32 daddr, __be32 saddr, u32 tos,
1885 struct flow_keys *hkeys)
1887 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1888 if (res->fi && res->fi->fib_nhs > 1) {
1889 int h = fib_multipath_hash(res->fi->fib_net, NULL, skb, hkeys);
1891 fib_select_multipath(res, h);
1895 /* create a routing cache entry */
1896 return __mkroute_input(skb, res, in_dev, daddr, saddr, tos);
1900 * NOTE. We drop all the packets that has local source
1901 * addresses, because every properly looped back packet
1902 * must have correct destination already attached by output routine.
1904 * Such approach solves two big problems:
1905 * 1. Not simplex devices are handled properly.
1906 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1907 * called with rcu_read_lock()
1910 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1911 u8 tos, struct net_device *dev,
1912 struct fib_result *res)
1914 struct in_device *in_dev = __in_dev_get_rcu(dev);
1915 struct flow_keys *flkeys = NULL, _flkeys;
1916 struct net *net = dev_net(dev);
1917 struct ip_tunnel_info *tun_info;
1919 unsigned int flags = 0;
1925 /* IP on this device is disabled. */
1930 /* Check for the most weird martians, which can be not detected
1934 tun_info = skb_tunnel_info(skb);
1935 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1936 fl4.flowi4_tun_key.tun_id = tun_info->key.tun_id;
1938 fl4.flowi4_tun_key.tun_id = 0;
1941 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
1942 goto martian_source;
1946 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
1949 /* Accept zero addresses only to limited broadcast;
1950 * I even do not know to fix it or not. Waiting for complains :-)
1952 if (ipv4_is_zeronet(saddr))
1953 goto martian_source;
1955 if (ipv4_is_zeronet(daddr))
1956 goto martian_destination;
1958 /* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(),
1959 * and call it once if daddr or/and saddr are loopback addresses
1961 if (ipv4_is_loopback(daddr)) {
1962 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
1963 goto martian_destination;
1964 } else if (ipv4_is_loopback(saddr)) {
1965 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
1966 goto martian_source;
1970 * Now we are ready to route packet.
1973 fl4.flowi4_iif = dev->ifindex;
1974 fl4.flowi4_mark = skb->mark;
1975 fl4.flowi4_tos = tos;
1976 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
1977 fl4.flowi4_flags = 0;
1980 fl4.flowi4_uid = sock_net_uid(net, NULL);
1982 if (fib4_rules_early_flow_dissect(net, skb, &fl4, &_flkeys)) {
1985 fl4.flowi4_proto = 0;
1990 err = fib_lookup(net, &fl4, res, 0);
1992 if (!IN_DEV_FORWARD(in_dev))
1993 err = -EHOSTUNREACH;
1997 if (res->type == RTN_BROADCAST) {
1998 if (IN_DEV_BFORWARD(in_dev))
2003 if (res->type == RTN_LOCAL) {
2004 err = fib_validate_source(skb, saddr, daddr, tos,
2005 0, dev, in_dev, &itag);
2007 goto martian_source;
2011 if (!IN_DEV_FORWARD(in_dev)) {
2012 err = -EHOSTUNREACH;
2015 if (res->type != RTN_UNICAST)
2016 goto martian_destination;
2019 err = ip_mkroute_input(skb, res, in_dev, daddr, saddr, tos, flkeys);
2023 if (skb->protocol != htons(ETH_P_IP))
2026 if (!ipv4_is_zeronet(saddr)) {
2027 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
2030 goto martian_source;
2032 flags |= RTCF_BROADCAST;
2033 res->type = RTN_BROADCAST;
2034 RT_CACHE_STAT_INC(in_brd);
2040 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
2041 if (rt_cache_valid(rth)) {
2042 skb_dst_set_noref(skb, &rth->dst);
2050 rth = rt_dst_alloc(l3mdev_master_dev_rcu(dev) ? : net->loopback_dev,
2051 flags | RTCF_LOCAL, res->type,
2052 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache);
2056 rth->dst.output= ip_rt_bug;
2057 #ifdef CONFIG_IP_ROUTE_CLASSID
2058 rth->dst.tclassid = itag;
2060 rth->rt_is_input = 1;
2062 RT_CACHE_STAT_INC(in_slow_tot);
2063 if (res->type == RTN_UNREACHABLE) {
2064 rth->dst.input= ip_error;
2065 rth->dst.error= -err;
2066 rth->rt_flags &= ~RTCF_LOCAL;
2070 struct fib_nh *nh = &FIB_RES_NH(*res);
2072 rth->dst.lwtstate = lwtstate_get(nh->nh_lwtstate);
2073 if (lwtunnel_input_redirect(rth->dst.lwtstate)) {
2074 WARN_ON(rth->dst.input == lwtunnel_input);
2075 rth->dst.lwtstate->orig_input = rth->dst.input;
2076 rth->dst.input = lwtunnel_input;
2079 if (unlikely(!rt_cache_route(nh, rth)))
2080 rt_add_uncached_list(rth);
2082 skb_dst_set(skb, &rth->dst);
2087 RT_CACHE_STAT_INC(in_no_route);
2088 res->type = RTN_UNREACHABLE;
2094 * Do not cache martian addresses: they should be logged (RFC1812)
2096 martian_destination:
2097 RT_CACHE_STAT_INC(in_martian_dst);
2098 #ifdef CONFIG_IP_ROUTE_VERBOSE
2099 if (IN_DEV_LOG_MARTIANS(in_dev))
2100 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
2101 &daddr, &saddr, dev->name);
2113 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
2117 int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2118 u8 tos, struct net_device *dev)
2120 struct fib_result res;
2123 tos &= IPTOS_RT_MASK;
2125 err = ip_route_input_rcu(skb, daddr, saddr, tos, dev, &res);
2130 EXPORT_SYMBOL(ip_route_input_noref);
2132 /* called with rcu_read_lock held */
2133 int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2134 u8 tos, struct net_device *dev, struct fib_result *res)
2136 /* Multicast recognition logic is moved from route cache to here.
2137 The problem was that too many Ethernet cards have broken/missing
2138 hardware multicast filters :-( As result the host on multicasting
2139 network acquires a lot of useless route cache entries, sort of
2140 SDR messages from all the world. Now we try to get rid of them.
2141 Really, provided software IP multicast filter is organized
2142 reasonably (at least, hashed), it does not result in a slowdown
2143 comparing with route cache reject entries.
2144 Note, that multicast routers are not affected, because
2145 route cache entry is created eventually.
2147 if (ipv4_is_multicast(daddr)) {
2148 struct in_device *in_dev = __in_dev_get_rcu(dev);
2153 our = ip_check_mc_rcu(in_dev, daddr, saddr,
2154 ip_hdr(skb)->protocol);
2156 /* check l3 master if no match yet */
2157 if ((!in_dev || !our) && netif_is_l3_slave(dev)) {
2158 struct in_device *l3_in_dev;
2160 l3_in_dev = __in_dev_get_rcu(skb->dev);
2162 our = ip_check_mc_rcu(l3_in_dev, daddr, saddr,
2163 ip_hdr(skb)->protocol);
2167 #ifdef CONFIG_IP_MROUTE
2169 (!ipv4_is_local_multicast(daddr) &&
2170 IN_DEV_MFORWARD(in_dev))
2173 err = ip_route_input_mc(skb, daddr, saddr,
2179 return ip_route_input_slow(skb, daddr, saddr, tos, dev, res);
2182 /* called with rcu_read_lock() */
2183 static struct rtable *__mkroute_output(const struct fib_result *res,
2184 const struct flowi4 *fl4, int orig_oif,
2185 struct net_device *dev_out,
2188 struct fib_info *fi = res->fi;
2189 struct fib_nh_exception *fnhe;
2190 struct in_device *in_dev;
2191 u16 type = res->type;
2195 in_dev = __in_dev_get_rcu(dev_out);
2197 return ERR_PTR(-EINVAL);
2199 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
2200 if (ipv4_is_loopback(fl4->saddr) &&
2201 !(dev_out->flags & IFF_LOOPBACK) &&
2202 !netif_is_l3_master(dev_out))
2203 return ERR_PTR(-EINVAL);
2205 if (ipv4_is_lbcast(fl4->daddr))
2206 type = RTN_BROADCAST;
2207 else if (ipv4_is_multicast(fl4->daddr))
2208 type = RTN_MULTICAST;
2209 else if (ipv4_is_zeronet(fl4->daddr))
2210 return ERR_PTR(-EINVAL);
2212 if (dev_out->flags & IFF_LOOPBACK)
2213 flags |= RTCF_LOCAL;
2216 if (type == RTN_BROADCAST) {
2217 flags |= RTCF_BROADCAST | RTCF_LOCAL;
2219 } else if (type == RTN_MULTICAST) {
2220 flags |= RTCF_MULTICAST | RTCF_LOCAL;
2221 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
2223 flags &= ~RTCF_LOCAL;
2226 /* If multicast route do not exist use
2227 * default one, but do not gateway in this case.
2230 if (fi && res->prefixlen < 4)
2232 } else if ((type == RTN_LOCAL) && (orig_oif != 0) &&
2233 (orig_oif != dev_out->ifindex)) {
2234 /* For local routes that require a particular output interface
2235 * we do not want to cache the result. Caching the result
2236 * causes incorrect behaviour when there are multiple source
2237 * addresses on the interface, the end result being that if the
2238 * intended recipient is waiting on that interface for the
2239 * packet he won't receive it because it will be delivered on
2240 * the loopback interface and the IP_PKTINFO ipi_ifindex will
2241 * be set to the loopback interface as well.
2247 do_cache &= fi != NULL;
2249 struct rtable __rcu **prth;
2250 struct fib_nh *nh = &FIB_RES_NH(*res);
2252 fnhe = find_exception(nh, fl4->daddr);
2256 prth = &fnhe->fnhe_rth_output;
2258 if (unlikely(fl4->flowi4_flags &
2259 FLOWI_FLAG_KNOWN_NH &&
2261 nh->nh_scope == RT_SCOPE_LINK))) {
2265 prth = raw_cpu_ptr(nh->nh_pcpu_rth_output);
2267 rth = rcu_dereference(*prth);
2268 if (rt_cache_valid(rth) && dst_hold_safe(&rth->dst))
2273 rth = rt_dst_alloc(dev_out, flags, type,
2274 IN_DEV_CONF_GET(in_dev, NOPOLICY),
2275 IN_DEV_CONF_GET(in_dev, NOXFRM),
2278 return ERR_PTR(-ENOBUFS);
2280 rth->rt_iif = orig_oif;
2282 RT_CACHE_STAT_INC(out_slow_tot);
2284 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
2285 if (flags & RTCF_LOCAL &&
2286 !(dev_out->flags & IFF_LOOPBACK)) {
2287 rth->dst.output = ip_mc_output;
2288 RT_CACHE_STAT_INC(out_slow_mc);
2290 #ifdef CONFIG_IP_MROUTE
2291 if (type == RTN_MULTICAST) {
2292 if (IN_DEV_MFORWARD(in_dev) &&
2293 !ipv4_is_local_multicast(fl4->daddr)) {
2294 rth->dst.input = ip_mr_input;
2295 rth->dst.output = ip_mc_output;
2301 rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0, do_cache);
2302 lwtunnel_set_redirect(&rth->dst);
2308 * Major route resolver routine.
2311 struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
2312 const struct sk_buff *skb)
2314 __u8 tos = RT_FL_TOS(fl4);
2315 struct fib_result res = {
2323 fl4->flowi4_iif = LOOPBACK_IFINDEX;
2324 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
2325 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
2326 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
2329 rth = ip_route_output_key_hash_rcu(net, fl4, &res, skb);
2334 EXPORT_SYMBOL_GPL(ip_route_output_key_hash);
2336 struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4 *fl4,
2337 struct fib_result *res,
2338 const struct sk_buff *skb)
2340 struct net_device *dev_out = NULL;
2341 int orig_oif = fl4->flowi4_oif;
2342 unsigned int flags = 0;
2344 int err = -ENETUNREACH;
2347 rth = ERR_PTR(-EINVAL);
2348 if (ipv4_is_multicast(fl4->saddr) ||
2349 ipv4_is_lbcast(fl4->saddr) ||
2350 ipv4_is_zeronet(fl4->saddr))
2353 /* I removed check for oif == dev_out->oif here.
2354 It was wrong for two reasons:
2355 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
2356 is assigned to multiple interfaces.
2357 2. Moreover, we are allowed to send packets with saddr
2358 of another iface. --ANK
2361 if (fl4->flowi4_oif == 0 &&
2362 (ipv4_is_multicast(fl4->daddr) ||
2363 ipv4_is_lbcast(fl4->daddr))) {
2364 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2365 dev_out = __ip_dev_find(net, fl4->saddr, false);
2369 /* Special hack: user can direct multicasts
2370 and limited broadcast via necessary interface
2371 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
2372 This hack is not just for fun, it allows
2373 vic,vat and friends to work.
2374 They bind socket to loopback, set ttl to zero
2375 and expect that it will work.
2376 From the viewpoint of routing cache they are broken,
2377 because we are not allowed to build multicast path
2378 with loopback source addr (look, routing cache
2379 cannot know, that ttl is zero, so that packet
2380 will not leave this host and route is valid).
2381 Luckily, this hack is good workaround.
2384 fl4->flowi4_oif = dev_out->ifindex;
2388 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
2389 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2390 if (!__ip_dev_find(net, fl4->saddr, false))
2396 if (fl4->flowi4_oif) {
2397 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
2398 rth = ERR_PTR(-ENODEV);
2402 /* RACE: Check return value of inet_select_addr instead. */
2403 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
2404 rth = ERR_PTR(-ENETUNREACH);
2407 if (ipv4_is_local_multicast(fl4->daddr) ||
2408 ipv4_is_lbcast(fl4->daddr) ||
2409 fl4->flowi4_proto == IPPROTO_IGMP) {
2411 fl4->saddr = inet_select_addr(dev_out, 0,
2416 if (ipv4_is_multicast(fl4->daddr))
2417 fl4->saddr = inet_select_addr(dev_out, 0,
2419 else if (!fl4->daddr)
2420 fl4->saddr = inet_select_addr(dev_out, 0,
2426 fl4->daddr = fl4->saddr;
2428 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
2429 dev_out = net->loopback_dev;
2430 fl4->flowi4_oif = LOOPBACK_IFINDEX;
2431 res->type = RTN_LOCAL;
2432 flags |= RTCF_LOCAL;
2436 err = fib_lookup(net, fl4, res, 0);
2440 if (fl4->flowi4_oif &&
2441 (ipv4_is_multicast(fl4->daddr) ||
2442 !netif_index_is_l3_master(net, fl4->flowi4_oif))) {
2443 /* Apparently, routing tables are wrong. Assume,
2444 that the destination is on link.
2447 Because we are allowed to send to iface
2448 even if it has NO routes and NO assigned
2449 addresses. When oif is specified, routing
2450 tables are looked up with only one purpose:
2451 to catch if destination is gatewayed, rather than
2452 direct. Moreover, if MSG_DONTROUTE is set,
2453 we send packet, ignoring both routing tables
2454 and ifaddr state. --ANK
2457 We could make it even if oif is unknown,
2458 likely IPv6, but we do not.
2461 if (fl4->saddr == 0)
2462 fl4->saddr = inet_select_addr(dev_out, 0,
2464 res->type = RTN_UNICAST;
2471 if (res->type == RTN_LOCAL) {
2473 if (res->fi->fib_prefsrc)
2474 fl4->saddr = res->fi->fib_prefsrc;
2476 fl4->saddr = fl4->daddr;
2479 /* L3 master device is the loopback for that domain */
2480 dev_out = l3mdev_master_dev_rcu(FIB_RES_DEV(*res)) ? :
2483 /* make sure orig_oif points to fib result device even
2484 * though packet rx/tx happens over loopback or l3mdev
2486 orig_oif = FIB_RES_OIF(*res);
2488 fl4->flowi4_oif = dev_out->ifindex;
2489 flags |= RTCF_LOCAL;
2493 fib_select_path(net, res, fl4, skb);
2495 dev_out = FIB_RES_DEV(*res);
2496 fl4->flowi4_oif = dev_out->ifindex;
2500 rth = __mkroute_output(res, fl4, orig_oif, dev_out, flags);
2506 static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2511 static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
2513 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2515 return mtu ? : dst->dev->mtu;
2518 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
2519 struct sk_buff *skb, u32 mtu)
2523 static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
2524 struct sk_buff *skb)
2528 static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
2534 static struct dst_ops ipv4_dst_blackhole_ops = {
2536 .check = ipv4_blackhole_dst_check,
2537 .mtu = ipv4_blackhole_mtu,
2538 .default_advmss = ipv4_default_advmss,
2539 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2540 .redirect = ipv4_rt_blackhole_redirect,
2541 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
2542 .neigh_lookup = ipv4_neigh_lookup,
2545 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2547 struct rtable *ort = (struct rtable *) dst_orig;
2550 rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_DEAD, 0);
2552 struct dst_entry *new = &rt->dst;
2555 new->input = dst_discard;
2556 new->output = dst_discard_out;
2558 new->dev = net->loopback_dev;
2562 rt->rt_is_input = ort->rt_is_input;
2563 rt->rt_iif = ort->rt_iif;
2564 rt->rt_pmtu = ort->rt_pmtu;
2565 rt->rt_mtu_locked = ort->rt_mtu_locked;
2567 rt->rt_genid = rt_genid_ipv4(net);
2568 rt->rt_flags = ort->rt_flags;
2569 rt->rt_type = ort->rt_type;
2570 rt->rt_gateway = ort->rt_gateway;
2571 rt->rt_uses_gateway = ort->rt_uses_gateway;
2573 INIT_LIST_HEAD(&rt->rt_uncached);
2576 dst_release(dst_orig);
2578 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2581 struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
2582 const struct sock *sk)
2584 struct rtable *rt = __ip_route_output_key(net, flp4);
2589 if (flp4->flowi4_proto)
2590 rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst,
2591 flowi4_to_flowi(flp4),
2596 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2598 /* called with rcu_read_lock held */
2599 static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
2600 struct rtable *rt, u32 table_id, struct flowi4 *fl4,
2601 struct sk_buff *skb, u32 portid, u32 seq)
2604 struct nlmsghdr *nlh;
2605 unsigned long expires = 0;
2607 u32 metrics[RTAX_MAX];
2609 nlh = nlmsg_put(skb, portid, seq, RTM_NEWROUTE, sizeof(*r), 0);
2613 r = nlmsg_data(nlh);
2614 r->rtm_family = AF_INET;
2615 r->rtm_dst_len = 32;
2617 r->rtm_tos = fl4->flowi4_tos;
2618 r->rtm_table = table_id < 256 ? table_id : RT_TABLE_COMPAT;
2619 if (nla_put_u32(skb, RTA_TABLE, table_id))
2620 goto nla_put_failure;
2621 r->rtm_type = rt->rt_type;
2622 r->rtm_scope = RT_SCOPE_UNIVERSE;
2623 r->rtm_protocol = RTPROT_UNSPEC;
2624 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2625 if (rt->rt_flags & RTCF_NOTIFY)
2626 r->rtm_flags |= RTM_F_NOTIFY;
2627 if (IPCB(skb)->flags & IPSKB_DOREDIRECT)
2628 r->rtm_flags |= RTCF_DOREDIRECT;
2630 if (nla_put_in_addr(skb, RTA_DST, dst))
2631 goto nla_put_failure;
2633 r->rtm_src_len = 32;
2634 if (nla_put_in_addr(skb, RTA_SRC, src))
2635 goto nla_put_failure;
2638 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2639 goto nla_put_failure;
2640 #ifdef CONFIG_IP_ROUTE_CLASSID
2641 if (rt->dst.tclassid &&
2642 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2643 goto nla_put_failure;
2645 if (!rt_is_input_route(rt) &&
2646 fl4->saddr != src) {
2647 if (nla_put_in_addr(skb, RTA_PREFSRC, fl4->saddr))
2648 goto nla_put_failure;
2650 if (rt->rt_uses_gateway &&
2651 nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gateway))
2652 goto nla_put_failure;
2654 expires = rt->dst.expires;
2656 unsigned long now = jiffies;
2658 if (time_before(now, expires))
2664 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
2665 if (rt->rt_pmtu && expires)
2666 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2667 if (rt->rt_mtu_locked && expires)
2668 metrics[RTAX_LOCK - 1] |= BIT(RTAX_MTU);
2669 if (rtnetlink_put_metrics(skb, metrics) < 0)
2670 goto nla_put_failure;
2672 if (fl4->flowi4_mark &&
2673 nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark))
2674 goto nla_put_failure;
2676 if (!uid_eq(fl4->flowi4_uid, INVALID_UID) &&
2677 nla_put_u32(skb, RTA_UID,
2678 from_kuid_munged(current_user_ns(), fl4->flowi4_uid)))
2679 goto nla_put_failure;
2681 error = rt->dst.error;
2683 if (rt_is_input_route(rt)) {
2684 #ifdef CONFIG_IP_MROUTE
2685 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2686 IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
2687 int err = ipmr_get_route(net, skb,
2688 fl4->saddr, fl4->daddr,
2694 goto nla_put_failure;
2698 if (nla_put_u32(skb, RTA_IIF, fl4->flowi4_iif))
2699 goto nla_put_failure;
2702 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
2703 goto nla_put_failure;
2705 nlmsg_end(skb, nlh);
2709 nlmsg_cancel(skb, nlh);
2713 static struct sk_buff *inet_rtm_getroute_build_skb(__be32 src, __be32 dst,
2714 u8 ip_proto, __be16 sport,
2717 struct sk_buff *skb;
2720 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2724 /* Reserve room for dummy headers, this skb can pass
2725 * through good chunk of routing engine.
2727 skb_reset_mac_header(skb);
2728 skb_reset_network_header(skb);
2729 skb->protocol = htons(ETH_P_IP);
2730 iph = skb_put(skb, sizeof(struct iphdr));
2731 iph->protocol = ip_proto;
2737 skb_set_transport_header(skb, skb->len);
2739 switch (iph->protocol) {
2741 struct udphdr *udph;
2743 udph = skb_put_zero(skb, sizeof(struct udphdr));
2744 udph->source = sport;
2746 udph->len = sizeof(struct udphdr);
2751 struct tcphdr *tcph;
2753 tcph = skb_put_zero(skb, sizeof(struct tcphdr));
2754 tcph->source = sport;
2756 tcph->doff = sizeof(struct tcphdr) / 4;
2758 tcph->check = ~tcp_v4_check(sizeof(struct tcphdr),
2762 case IPPROTO_ICMP: {
2763 struct icmphdr *icmph;
2765 icmph = skb_put_zero(skb, sizeof(struct icmphdr));
2766 icmph->type = ICMP_ECHO;
2774 static int inet_rtm_valid_getroute_req(struct sk_buff *skb,
2775 const struct nlmsghdr *nlh,
2777 struct netlink_ext_ack *extack)
2782 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
2783 NL_SET_ERR_MSG(extack,
2784 "ipv4: Invalid header for route get request");
2788 if (!netlink_strict_get_check(skb))
2789 return nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX,
2790 rtm_ipv4_policy, extack);
2792 rtm = nlmsg_data(nlh);
2793 if ((rtm->rtm_src_len && rtm->rtm_src_len != 32) ||
2794 (rtm->rtm_dst_len && rtm->rtm_dst_len != 32) ||
2795 rtm->rtm_table || rtm->rtm_protocol ||
2796 rtm->rtm_scope || rtm->rtm_type) {
2797 NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for route get request");
2801 if (rtm->rtm_flags & ~(RTM_F_NOTIFY |
2802 RTM_F_LOOKUP_TABLE |
2804 NL_SET_ERR_MSG(extack, "ipv4: Unsupported rtm_flags for route get request");
2808 err = nlmsg_parse_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
2809 rtm_ipv4_policy, extack);
2813 if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
2814 (tb[RTA_DST] && !rtm->rtm_dst_len)) {
2815 NL_SET_ERR_MSG(extack, "ipv4: rtm_src_len and rtm_dst_len must be 32 for IPv4");
2819 for (i = 0; i <= RTA_MAX; i++) {
2835 NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in route get request");
2843 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2844 struct netlink_ext_ack *extack)
2846 struct net *net = sock_net(in_skb->sk);
2847 struct nlattr *tb[RTA_MAX+1];
2848 u32 table_id = RT_TABLE_MAIN;
2849 __be16 sport = 0, dport = 0;
2850 struct fib_result res = {};
2851 u8 ip_proto = IPPROTO_UDP;
2852 struct rtable *rt = NULL;
2853 struct sk_buff *skb;
2855 struct flowi4 fl4 = {};
2863 err = inet_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
2867 rtm = nlmsg_data(nlh);
2868 src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
2869 dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
2870 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2871 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2873 uid = make_kuid(current_user_ns(), nla_get_u32(tb[RTA_UID]));
2875 uid = (iif ? INVALID_UID : current_uid());
2877 if (tb[RTA_IP_PROTO]) {
2878 err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
2879 &ip_proto, AF_INET, extack);
2885 sport = nla_get_be16(tb[RTA_SPORT]);
2888 dport = nla_get_be16(tb[RTA_DPORT]);
2890 skb = inet_rtm_getroute_build_skb(src, dst, ip_proto, sport, dport);
2896 fl4.flowi4_tos = rtm->rtm_tos;
2897 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2898 fl4.flowi4_mark = mark;
2899 fl4.flowi4_uid = uid;
2901 fl4.fl4_sport = sport;
2903 fl4.fl4_dport = dport;
2904 fl4.flowi4_proto = ip_proto;
2909 struct net_device *dev;
2911 dev = dev_get_by_index_rcu(net, iif);
2917 fl4.flowi4_iif = iif; /* for rt_fill_info */
2920 err = ip_route_input_rcu(skb, dst, src, rtm->rtm_tos,
2923 rt = skb_rtable(skb);
2924 if (err == 0 && rt->dst.error)
2925 err = -rt->dst.error;
2927 fl4.flowi4_iif = LOOPBACK_IFINDEX;
2928 skb->dev = net->loopback_dev;
2929 rt = ip_route_output_key_hash_rcu(net, &fl4, &res, skb);
2934 skb_dst_set(skb, &rt->dst);
2940 if (rtm->rtm_flags & RTM_F_NOTIFY)
2941 rt->rt_flags |= RTCF_NOTIFY;
2943 if (rtm->rtm_flags & RTM_F_LOOKUP_TABLE)
2944 table_id = res.table ? res.table->tb_id : 0;
2946 /* reset skb for netlink reply msg */
2948 skb_reset_network_header(skb);
2949 skb_reset_transport_header(skb);
2950 skb_reset_mac_header(skb);
2952 if (rtm->rtm_flags & RTM_F_FIB_MATCH) {
2954 err = fib_props[res.type].error;
2956 err = -EHOSTUNREACH;
2959 err = fib_dump_info(skb, NETLINK_CB(in_skb).portid,
2960 nlh->nlmsg_seq, RTM_NEWROUTE, table_id,
2961 rt->rt_type, res.prefix, res.prefixlen,
2962 fl4.flowi4_tos, res.fi, 0);
2964 err = rt_fill_info(net, dst, src, rt, table_id, &fl4, skb,
2965 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq);
2972 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2982 void ip_rt_multicast_event(struct in_device *in_dev)
2984 rt_cache_flush(dev_net(in_dev->dev));
2987 #ifdef CONFIG_SYSCTL
2988 static int ip_rt_gc_interval __read_mostly = 60 * HZ;
2989 static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
2990 static int ip_rt_gc_elasticity __read_mostly = 8;
2991 static int ip_min_valid_pmtu __read_mostly = IPV4_MIN_MTU;
2993 static int ipv4_sysctl_rtcache_flush(struct ctl_table *__ctl, int write,
2994 void __user *buffer,
2995 size_t *lenp, loff_t *ppos)
2997 struct net *net = (struct net *)__ctl->extra1;
3000 rt_cache_flush(net);
3001 fnhe_genid_bump(net);
3008 static struct ctl_table ipv4_route_table[] = {
3010 .procname = "gc_thresh",
3011 .data = &ipv4_dst_ops.gc_thresh,
3012 .maxlen = sizeof(int),
3014 .proc_handler = proc_dointvec,
3017 .procname = "max_size",
3018 .data = &ip_rt_max_size,
3019 .maxlen = sizeof(int),
3021 .proc_handler = proc_dointvec,
3024 /* Deprecated. Use gc_min_interval_ms */
3026 .procname = "gc_min_interval",
3027 .data = &ip_rt_gc_min_interval,
3028 .maxlen = sizeof(int),
3030 .proc_handler = proc_dointvec_jiffies,
3033 .procname = "gc_min_interval_ms",
3034 .data = &ip_rt_gc_min_interval,
3035 .maxlen = sizeof(int),
3037 .proc_handler = proc_dointvec_ms_jiffies,
3040 .procname = "gc_timeout",
3041 .data = &ip_rt_gc_timeout,
3042 .maxlen = sizeof(int),
3044 .proc_handler = proc_dointvec_jiffies,
3047 .procname = "gc_interval",
3048 .data = &ip_rt_gc_interval,
3049 .maxlen = sizeof(int),
3051 .proc_handler = proc_dointvec_jiffies,
3054 .procname = "redirect_load",
3055 .data = &ip_rt_redirect_load,
3056 .maxlen = sizeof(int),
3058 .proc_handler = proc_dointvec,
3061 .procname = "redirect_number",
3062 .data = &ip_rt_redirect_number,
3063 .maxlen = sizeof(int),
3065 .proc_handler = proc_dointvec,
3068 .procname = "redirect_silence",
3069 .data = &ip_rt_redirect_silence,
3070 .maxlen = sizeof(int),
3072 .proc_handler = proc_dointvec,
3075 .procname = "error_cost",
3076 .data = &ip_rt_error_cost,
3077 .maxlen = sizeof(int),
3079 .proc_handler = proc_dointvec,
3082 .procname = "error_burst",
3083 .data = &ip_rt_error_burst,
3084 .maxlen = sizeof(int),
3086 .proc_handler = proc_dointvec,
3089 .procname = "gc_elasticity",
3090 .data = &ip_rt_gc_elasticity,
3091 .maxlen = sizeof(int),
3093 .proc_handler = proc_dointvec,
3096 .procname = "mtu_expires",
3097 .data = &ip_rt_mtu_expires,
3098 .maxlen = sizeof(int),
3100 .proc_handler = proc_dointvec_jiffies,
3103 .procname = "min_pmtu",
3104 .data = &ip_rt_min_pmtu,
3105 .maxlen = sizeof(int),
3107 .proc_handler = proc_dointvec_minmax,
3108 .extra1 = &ip_min_valid_pmtu,
3111 .procname = "min_adv_mss",
3112 .data = &ip_rt_min_advmss,
3113 .maxlen = sizeof(int),
3115 .proc_handler = proc_dointvec,
3120 static struct ctl_table ipv4_route_flush_table[] = {
3122 .procname = "flush",
3123 .maxlen = sizeof(int),
3125 .proc_handler = ipv4_sysctl_rtcache_flush,
3130 static __net_init int sysctl_route_net_init(struct net *net)
3132 struct ctl_table *tbl;
3134 tbl = ipv4_route_flush_table;
3135 if (!net_eq(net, &init_net)) {
3136 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
3140 /* Don't export sysctls to unprivileged users */
3141 if (net->user_ns != &init_user_ns)
3142 tbl[0].procname = NULL;
3144 tbl[0].extra1 = net;
3146 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
3147 if (!net->ipv4.route_hdr)
3152 if (tbl != ipv4_route_flush_table)
3158 static __net_exit void sysctl_route_net_exit(struct net *net)
3160 struct ctl_table *tbl;
3162 tbl = net->ipv4.route_hdr->ctl_table_arg;
3163 unregister_net_sysctl_table(net->ipv4.route_hdr);
3164 BUG_ON(tbl == ipv4_route_flush_table);
3168 static __net_initdata struct pernet_operations sysctl_route_ops = {
3169 .init = sysctl_route_net_init,
3170 .exit = sysctl_route_net_exit,
3174 static __net_init int rt_genid_init(struct net *net)
3176 atomic_set(&net->ipv4.rt_genid, 0);
3177 atomic_set(&net->fnhe_genid, 0);
3178 atomic_set(&net->ipv4.dev_addr_genid, get_random_int());
3182 static __net_initdata struct pernet_operations rt_genid_ops = {
3183 .init = rt_genid_init,
3186 static int __net_init ipv4_inetpeer_init(struct net *net)
3188 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3192 inet_peer_base_init(bp);
3193 net->ipv4.peers = bp;
3197 static void __net_exit ipv4_inetpeer_exit(struct net *net)
3199 struct inet_peer_base *bp = net->ipv4.peers;
3201 net->ipv4.peers = NULL;
3202 inetpeer_invalidate_tree(bp);
3206 static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
3207 .init = ipv4_inetpeer_init,
3208 .exit = ipv4_inetpeer_exit,
3211 #ifdef CONFIG_IP_ROUTE_CLASSID
3212 struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
3213 #endif /* CONFIG_IP_ROUTE_CLASSID */
3215 int __init ip_rt_init(void)
3219 ip_idents = kmalloc_array(IP_IDENTS_SZ, sizeof(*ip_idents),
3222 panic("IP: failed to allocate ip_idents\n");
3224 prandom_bytes(ip_idents, IP_IDENTS_SZ * sizeof(*ip_idents));
3226 ip_tstamps = kcalloc(IP_IDENTS_SZ, sizeof(*ip_tstamps), GFP_KERNEL);
3228 panic("IP: failed to allocate ip_tstamps\n");
3230 for_each_possible_cpu(cpu) {
3231 struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
3233 INIT_LIST_HEAD(&ul->head);
3234 spin_lock_init(&ul->lock);
3236 #ifdef CONFIG_IP_ROUTE_CLASSID
3237 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
3239 panic("IP: failed to allocate ip_rt_acct\n");
3242 ipv4_dst_ops.kmem_cachep =
3243 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
3244 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
3246 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
3248 if (dst_entries_init(&ipv4_dst_ops) < 0)
3249 panic("IP: failed to allocate ipv4_dst_ops counter\n");
3251 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
3252 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
3254 ipv4_dst_ops.gc_thresh = ~0;
3255 ip_rt_max_size = INT_MAX;
3260 if (ip_rt_proc_init())
3261 pr_err("Unable to create route proc files\n");
3266 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL,
3267 RTNL_FLAG_DOIT_UNLOCKED);
3269 #ifdef CONFIG_SYSCTL
3270 register_pernet_subsys(&sysctl_route_ops);
3272 register_pernet_subsys(&rt_genid_ops);
3273 register_pernet_subsys(&ipv4_inetpeer_ops);
3277 #ifdef CONFIG_SYSCTL
3279 * We really need to sanitize the damn ipv4 init order, then all
3280 * this nonsense will go away.
3282 void __init ip_static_sysctl_init(void)
3284 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);