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65#define pr_fmt(fmt) "IPv4: " fmt
66
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>
72#include <linux/mm.h>
73#include <linux/string.h>
74#include <linux/socket.h>
75#include <linux/sockios.h>
76#include <linux/errno.h>
77#include <linux/in.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>
93#include <net/dst.h>
94#include <net/dst_metadata.h>
95#include <net/net_namespace.h>
96#include <net/protocol.h>
97#include <net/ip.h>
98#include <net/route.h>
99#include <net/inetpeer.h>
100#include <net/sock.h>
101#include <net/ip_fib.h>
102#include <net/arp.h>
103#include <net/tcp.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>
109#ifdef CONFIG_SYSCTL
110#include <linux/sysctl.h>
111#include <linux/kmemleak.h>
112#endif
113#include <net/secure_seq.h>
114#include <net/ip_tunnels.h>
115#include <net/l3mdev.h>
116
117#include "fib_lookup.h"
118
119#define RT_FL_TOS(oldflp4) \
120 ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
121
122#define RT_GC_TIMEOUT (300*HZ)
123
124static int ip_rt_max_size;
125static int ip_rt_redirect_number __read_mostly = 9;
126static int ip_rt_redirect_load __read_mostly = HZ / 50;
127static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
128static int ip_rt_error_cost __read_mostly = HZ;
129static int ip_rt_error_burst __read_mostly = 5 * HZ;
130static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
131static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
132static int ip_rt_min_advmss __read_mostly = 256;
133
134static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
135
136
137
138
139static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
140static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
141static unsigned int ipv4_mtu(const struct dst_entry *dst);
142static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
143static void ipv4_link_failure(struct sk_buff *skb);
144static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
145 struct sk_buff *skb, u32 mtu);
146static void ip_do_redirect(struct dst_entry *dst, struct sock *sk,
147 struct sk_buff *skb);
148static void ipv4_dst_destroy(struct dst_entry *dst);
149
150static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
151{
152 WARN_ON(1);
153 return NULL;
154}
155
156static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
157 struct sk_buff *skb,
158 const void *daddr);
159static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr);
160
161static struct dst_ops ipv4_dst_ops = {
162 .family = AF_INET,
163 .check = ipv4_dst_check,
164 .default_advmss = ipv4_default_advmss,
165 .mtu = ipv4_mtu,
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,
175};
176
177#define ECN_OR_COST(class) TC_PRIO_##class
178
179const __u8 ip_tos2prio[16] = {
180 TC_PRIO_BESTEFFORT,
181 ECN_OR_COST(BESTEFFORT),
182 TC_PRIO_BESTEFFORT,
183 ECN_OR_COST(BESTEFFORT),
184 TC_PRIO_BULK,
185 ECN_OR_COST(BULK),
186 TC_PRIO_BULK,
187 ECN_OR_COST(BULK),
188 TC_PRIO_INTERACTIVE,
189 ECN_OR_COST(INTERACTIVE),
190 TC_PRIO_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)
196};
197EXPORT_SYMBOL(ip_tos2prio);
198
199static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
200#define RT_CACHE_STAT_INC(field) raw_cpu_inc(rt_cache_stat.field)
201
202#ifdef CONFIG_PROC_FS
203static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
204{
205 if (*pos)
206 return NULL;
207 return SEQ_START_TOKEN;
208}
209
210static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
211{
212 ++*pos;
213 return NULL;
214}
215
216static void rt_cache_seq_stop(struct seq_file *seq, void *v)
217{
218}
219
220static int rt_cache_seq_show(struct seq_file *seq, void *v)
221{
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"
226 "HHUptod\tSpecDst");
227 return 0;
228}
229
230static 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,
235};
236
237static int rt_cache_seq_open(struct inode *inode, struct file *file)
238{
239 return seq_open(file, &rt_cache_seq_ops);
240}
241
242static const struct file_operations rt_cache_seq_fops = {
243 .owner = THIS_MODULE,
244 .open = rt_cache_seq_open,
245 .read = seq_read,
246 .llseek = seq_lseek,
247 .release = seq_release,
248};
249
250
251static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
252{
253 int cpu;
254
255 if (*pos == 0)
256 return SEQ_START_TOKEN;
257
258 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
259 if (!cpu_possible(cpu))
260 continue;
261 *pos = cpu+1;
262 return &per_cpu(rt_cache_stat, cpu);
263 }
264 return NULL;
265}
266
267static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
268{
269 int cpu;
270
271 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
272 if (!cpu_possible(cpu))
273 continue;
274 *pos = cpu+1;
275 return &per_cpu(rt_cache_stat, cpu);
276 }
277 return NULL;
278
279}
280
281static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
282{
283
284}
285
286static int rt_cpu_seq_show(struct seq_file *seq, void *v)
287{
288 struct rt_cache_stat *st = v;
289
290 if (v == SEQ_START_TOKEN) {
291 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");
292 return 0;
293 }
294
295 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
296 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
297 dst_entries_get_slow(&ipv4_dst_ops),
298 0,
299 st->in_slow_tot,
300 st->in_slow_mc,
301 st->in_no_route,
302 st->in_brd,
303 st->in_martian_dst,
304 st->in_martian_src,
305
306 0,
307 st->out_slow_tot,
308 st->out_slow_mc,
309
310 0,
311 0,
312 0,
313 0,
314 0,
315 0
316 );
317 return 0;
318}
319
320static const struct seq_operations rt_cpu_seq_ops = {
321 .start = rt_cpu_seq_start,
322 .next = rt_cpu_seq_next,
323 .stop = rt_cpu_seq_stop,
324 .show = rt_cpu_seq_show,
325};
326
327
328static int rt_cpu_seq_open(struct inode *inode, struct file *file)
329{
330 return seq_open(file, &rt_cpu_seq_ops);
331}
332
333static const struct file_operations rt_cpu_seq_fops = {
334 .owner = THIS_MODULE,
335 .open = rt_cpu_seq_open,
336 .read = seq_read,
337 .llseek = seq_lseek,
338 .release = seq_release,
339};
340
341#ifdef CONFIG_IP_ROUTE_CLASSID
342static int rt_acct_proc_show(struct seq_file *m, void *v)
343{
344 struct ip_rt_acct *dst, *src;
345 unsigned int i, j;
346
347 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
348 if (!dst)
349 return -ENOMEM;
350
351 for_each_possible_cpu(i) {
352 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
353 for (j = 0; j < 256; j++) {
354 dst[j].o_bytes += src[j].o_bytes;
355 dst[j].o_packets += src[j].o_packets;
356 dst[j].i_bytes += src[j].i_bytes;
357 dst[j].i_packets += src[j].i_packets;
358 }
359 }
360
361 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
362 kfree(dst);
363 return 0;
364}
365
366static int rt_acct_proc_open(struct inode *inode, struct file *file)
367{
368 return single_open(file, rt_acct_proc_show, NULL);
369}
370
371static const struct file_operations rt_acct_proc_fops = {
372 .owner = THIS_MODULE,
373 .open = rt_acct_proc_open,
374 .read = seq_read,
375 .llseek = seq_lseek,
376 .release = single_release,
377};
378#endif
379
380static int __net_init ip_rt_do_proc_init(struct net *net)
381{
382 struct proc_dir_entry *pde;
383
384 pde = proc_create("rt_cache", S_IRUGO, net->proc_net,
385 &rt_cache_seq_fops);
386 if (!pde)
387 goto err1;
388
389 pde = proc_create("rt_cache", S_IRUGO,
390 net->proc_net_stat, &rt_cpu_seq_fops);
391 if (!pde)
392 goto err2;
393
394#ifdef CONFIG_IP_ROUTE_CLASSID
395 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
396 if (!pde)
397 goto err3;
398#endif
399 return 0;
400
401#ifdef CONFIG_IP_ROUTE_CLASSID
402err3:
403 remove_proc_entry("rt_cache", net->proc_net_stat);
404#endif
405err2:
406 remove_proc_entry("rt_cache", net->proc_net);
407err1:
408 return -ENOMEM;
409}
410
411static void __net_exit ip_rt_do_proc_exit(struct net *net)
412{
413 remove_proc_entry("rt_cache", net->proc_net_stat);
414 remove_proc_entry("rt_cache", net->proc_net);
415#ifdef CONFIG_IP_ROUTE_CLASSID
416 remove_proc_entry("rt_acct", net->proc_net);
417#endif
418}
419
420static struct pernet_operations ip_rt_proc_ops __net_initdata = {
421 .init = ip_rt_do_proc_init,
422 .exit = ip_rt_do_proc_exit,
423};
424
425static int __init ip_rt_proc_init(void)
426{
427 return register_pernet_subsys(&ip_rt_proc_ops);
428}
429
430#else
431static inline int ip_rt_proc_init(void)
432{
433 return 0;
434}
435#endif
436
437static inline bool rt_is_expired(const struct rtable *rth)
438{
439 return rth->rt_genid != rt_genid_ipv4(dev_net(rth->dst.dev));
440}
441
442void rt_cache_flush(struct net *net)
443{
444 rt_genid_bump_ipv4(net);
445}
446
447static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
448 struct sk_buff *skb,
449 const void *daddr)
450{
451 struct net_device *dev = dst->dev;
452 const __be32 *pkey = daddr;
453 const struct rtable *rt;
454 struct neighbour *n;
455
456 rt = (const struct rtable *) dst;
457 if (rt->rt_gateway)
458 pkey = (const __be32 *) &rt->rt_gateway;
459 else if (skb)
460 pkey = &ip_hdr(skb)->daddr;
461
462 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
463 if (n)
464 return n;
465 return neigh_create(&arp_tbl, pkey, dev);
466}
467
468static void ipv4_confirm_neigh(const struct dst_entry *dst, const void *daddr)
469{
470 struct net_device *dev = dst->dev;
471 const __be32 *pkey = daddr;
472 const struct rtable *rt;
473
474 rt = (const struct rtable *)dst;
475 if (rt->rt_gateway)
476 pkey = (const __be32 *)&rt->rt_gateway;
477 else if (!daddr ||
478 (rt->rt_flags &
479 (RTCF_MULTICAST | RTCF_BROADCAST | RTCF_LOCAL)))
480 return;
481
482 __ipv4_confirm_neigh(dev, *(__force u32 *)pkey);
483}
484
485#define IP_IDENTS_SZ 2048u
486
487static atomic_t *ip_idents __read_mostly;
488static u32 *ip_tstamps __read_mostly;
489
490
491
492
493
494u32 ip_idents_reserve(u32 hash, int segs)
495{
496 u32 *p_tstamp = ip_tstamps + hash % IP_IDENTS_SZ;
497 atomic_t *p_id = ip_idents + hash % IP_IDENTS_SZ;
498 u32 old = ACCESS_ONCE(*p_tstamp);
499 u32 now = (u32)jiffies;
500 u32 new, delta = 0;
501
502 if (old != now && cmpxchg(p_tstamp, old, now) == old)
503 delta = prandom_u32_max(now - old);
504
505
506 do {
507 old = (u32)atomic_read(p_id);
508 new = old + delta + segs;
509 } while (atomic_cmpxchg(p_id, old, new) != old);
510
511 return new - segs;
512}
513EXPORT_SYMBOL(ip_idents_reserve);
514
515void __ip_select_ident(struct net *net, struct iphdr *iph, int segs)
516{
517 static u32 ip_idents_hashrnd __read_mostly;
518 u32 hash, id;
519
520 net_get_random_once(&ip_idents_hashrnd, sizeof(ip_idents_hashrnd));
521
522 hash = jhash_3words((__force u32)iph->daddr,
523 (__force u32)iph->saddr,
524 iph->protocol ^ net_hash_mix(net),
525 ip_idents_hashrnd);
526 id = ip_idents_reserve(hash, segs);
527 iph->id = htons(id);
528}
529EXPORT_SYMBOL(__ip_select_ident);
530
531static void __build_flow_key(const struct net *net, struct flowi4 *fl4,
532 const struct sock *sk,
533 const struct iphdr *iph,
534 int oif, u8 tos,
535 u8 prot, u32 mark, int flow_flags)
536{
537 if (sk) {
538 const struct inet_sock *inet = inet_sk(sk);
539
540 oif = sk->sk_bound_dev_if;
541 mark = sk->sk_mark;
542 tos = RT_CONN_FLAGS(sk);
543 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
544 }
545 flowi4_init_output(fl4, oif, mark, tos,
546 RT_SCOPE_UNIVERSE, prot,
547 flow_flags,
548 iph->daddr, iph->saddr, 0, 0,
549 sock_net_uid(net, sk));
550}
551
552static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
553 const struct sock *sk)
554{
555 const struct net *net = dev_net(skb->dev);
556 const struct iphdr *iph = ip_hdr(skb);
557 int oif = skb->dev->ifindex;
558 u8 tos = RT_TOS(iph->tos);
559 u8 prot = iph->protocol;
560 u32 mark = skb->mark;
561
562 __build_flow_key(net, fl4, sk, iph, oif, tos, prot, mark, 0);
563}
564
565static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
566{
567 const struct inet_sock *inet = inet_sk(sk);
568 const struct ip_options_rcu *inet_opt;
569 __be32 daddr = inet->inet_daddr;
570
571 rcu_read_lock();
572 inet_opt = rcu_dereference(inet->inet_opt);
573 if (inet_opt && inet_opt->opt.srr)
574 daddr = inet_opt->opt.faddr;
575 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
576 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
577 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
578 inet_sk_flowi_flags(sk),
579 daddr, inet->inet_saddr, 0, 0, sk->sk_uid);
580 rcu_read_unlock();
581}
582
583static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
584 const struct sk_buff *skb)
585{
586 if (skb)
587 build_skb_flow_key(fl4, skb, sk);
588 else
589 build_sk_flow_key(fl4, sk);
590}
591
592static DEFINE_SPINLOCK(fnhe_lock);
593
594static void fnhe_flush_routes(struct fib_nh_exception *fnhe)
595{
596 struct rtable *rt;
597
598 rt = rcu_dereference(fnhe->fnhe_rth_input);
599 if (rt) {
600 RCU_INIT_POINTER(fnhe->fnhe_rth_input, NULL);
601 dst_dev_put(&rt->dst);
602 dst_release(&rt->dst);
603 }
604 rt = rcu_dereference(fnhe->fnhe_rth_output);
605 if (rt) {
606 RCU_INIT_POINTER(fnhe->fnhe_rth_output, NULL);
607 dst_dev_put(&rt->dst);
608 dst_release(&rt->dst);
609 }
610}
611
612static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
613{
614 struct fib_nh_exception *fnhe, *oldest;
615
616 oldest = rcu_dereference(hash->chain);
617 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
618 fnhe = rcu_dereference(fnhe->fnhe_next)) {
619 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
620 oldest = fnhe;
621 }
622 fnhe_flush_routes(oldest);
623 return oldest;
624}
625
626static inline u32 fnhe_hashfun(__be32 daddr)
627{
628 static u32 fnhe_hashrnd __read_mostly;
629 u32 hval;
630
631 net_get_random_once(&fnhe_hashrnd, sizeof(fnhe_hashrnd));
632 hval = jhash_1word((__force u32) daddr, fnhe_hashrnd);
633 return hash_32(hval, FNHE_HASH_SHIFT);
634}
635
636static void fill_route_from_fnhe(struct rtable *rt, struct fib_nh_exception *fnhe)
637{
638 rt->rt_pmtu = fnhe->fnhe_pmtu;
639 rt->dst.expires = fnhe->fnhe_expires;
640
641 if (fnhe->fnhe_gw) {
642 rt->rt_flags |= RTCF_REDIRECTED;
643 rt->rt_gateway = fnhe->fnhe_gw;
644 rt->rt_uses_gateway = 1;
645 }
646}
647
648static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
649 u32 pmtu, unsigned long expires)
650{
651 struct fnhe_hash_bucket *hash;
652 struct fib_nh_exception *fnhe;
653 struct rtable *rt;
654 unsigned int i;
655 int depth;
656 u32 hval = fnhe_hashfun(daddr);
657
658 spin_lock_bh(&fnhe_lock);
659
660 hash = rcu_dereference(nh->nh_exceptions);
661 if (!hash) {
662 hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC);
663 if (!hash)
664 goto out_unlock;
665 rcu_assign_pointer(nh->nh_exceptions, hash);
666 }
667
668 hash += hval;
669
670 depth = 0;
671 for (fnhe = rcu_dereference(hash->chain); fnhe;
672 fnhe = rcu_dereference(fnhe->fnhe_next)) {
673 if (fnhe->fnhe_daddr == daddr)
674 break;
675 depth++;
676 }
677
678 if (fnhe) {
679 if (gw)
680 fnhe->fnhe_gw = gw;
681 if (pmtu) {
682 fnhe->fnhe_pmtu = pmtu;
683 fnhe->fnhe_expires = max(1UL, expires);
684 }
685
686 rt = rcu_dereference(fnhe->fnhe_rth_input);
687 if (rt)
688 fill_route_from_fnhe(rt, fnhe);
689 rt = rcu_dereference(fnhe->fnhe_rth_output);
690 if (rt)
691 fill_route_from_fnhe(rt, fnhe);
692 } else {
693 if (depth > FNHE_RECLAIM_DEPTH)
694 fnhe = fnhe_oldest(hash);
695 else {
696 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
697 if (!fnhe)
698 goto out_unlock;
699
700 fnhe->fnhe_next = hash->chain;
701 rcu_assign_pointer(hash->chain, fnhe);
702 }
703 fnhe->fnhe_genid = fnhe_genid(dev_net(nh->nh_dev));
704 fnhe->fnhe_daddr = daddr;
705 fnhe->fnhe_gw = gw;
706 fnhe->fnhe_pmtu = pmtu;
707 fnhe->fnhe_expires = expires;
708
709
710
711
712
713 rt = rcu_dereference(nh->nh_rth_input);
714 if (rt)
715 rt->dst.obsolete = DST_OBSOLETE_KILL;
716
717 for_each_possible_cpu(i) {
718 struct rtable __rcu **prt;
719 prt = per_cpu_ptr(nh->nh_pcpu_rth_output, i);
720 rt = rcu_dereference(*prt);
721 if (rt)
722 rt->dst.obsolete = DST_OBSOLETE_KILL;
723 }
724 }
725
726 fnhe->fnhe_stamp = jiffies;
727
728out_unlock:
729 spin_unlock_bh(&fnhe_lock);
730}
731
732static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4,
733 bool kill_route)
734{
735 __be32 new_gw = icmp_hdr(skb)->un.gateway;
736 __be32 old_gw = ip_hdr(skb)->saddr;
737 struct net_device *dev = skb->dev;
738 struct in_device *in_dev;
739 struct fib_result res;
740 struct neighbour *n;
741 struct net *net;
742
743 switch (icmp_hdr(skb)->code & 7) {
744 case ICMP_REDIR_NET:
745 case ICMP_REDIR_NETTOS:
746 case ICMP_REDIR_HOST:
747 case ICMP_REDIR_HOSTTOS:
748 break;
749
750 default:
751 return;
752 }
753
754 if (rt->rt_gateway != old_gw)
755 return;
756
757 in_dev = __in_dev_get_rcu(dev);
758 if (!in_dev)
759 return;
760
761 net = dev_net(dev);
762 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
763 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
764 ipv4_is_zeronet(new_gw))
765 goto reject_redirect;
766
767 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
768 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
769 goto reject_redirect;
770 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
771 goto reject_redirect;
772 } else {
773 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
774 goto reject_redirect;
775 }
776
777 n = __ipv4_neigh_lookup(rt->dst.dev, new_gw);
778 if (!n)
779 n = neigh_create(&arp_tbl, &new_gw, rt->dst.dev);
780 if (!IS_ERR(n)) {
781 if (!(n->nud_state & NUD_VALID)) {
782 neigh_event_send(n, NULL);
783 } else {
784 if (fib_lookup(net, fl4, &res, 0) == 0) {
785 struct fib_nh *nh = &FIB_RES_NH(res);
786
787 update_or_create_fnhe(nh, fl4->daddr, new_gw,
788 0, jiffies + ip_rt_gc_timeout);
789 }
790 if (kill_route)
791 rt->dst.obsolete = DST_OBSOLETE_KILL;
792 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
793 }
794 neigh_release(n);
795 }
796 return;
797
798reject_redirect:
799#ifdef CONFIG_IP_ROUTE_VERBOSE
800 if (IN_DEV_LOG_MARTIANS(in_dev)) {
801 const struct iphdr *iph = (const struct iphdr *) skb->data;
802 __be32 daddr = iph->daddr;
803 __be32 saddr = iph->saddr;
804
805 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
806 " Advised path = %pI4 -> %pI4\n",
807 &old_gw, dev->name, &new_gw,
808 &saddr, &daddr);
809 }
810#endif
811 ;
812}
813
814static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
815{
816 struct rtable *rt;
817 struct flowi4 fl4;
818 const struct iphdr *iph = (const struct iphdr *) skb->data;
819 struct net *net = dev_net(skb->dev);
820 int oif = skb->dev->ifindex;
821 u8 tos = RT_TOS(iph->tos);
822 u8 prot = iph->protocol;
823 u32 mark = skb->mark;
824
825 rt = (struct rtable *) dst;
826
827 __build_flow_key(net, &fl4, sk, iph, oif, tos, prot, mark, 0);
828 __ip_do_redirect(rt, skb, &fl4, true);
829}
830
831static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
832{
833 struct rtable *rt = (struct rtable *)dst;
834 struct dst_entry *ret = dst;
835
836 if (rt) {
837 if (dst->obsolete > 0) {
838 ip_rt_put(rt);
839 ret = NULL;
840 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
841 rt->dst.expires) {
842 ip_rt_put(rt);
843 ret = NULL;
844 }
845 }
846 return ret;
847}
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865void ip_rt_send_redirect(struct sk_buff *skb)
866{
867 struct rtable *rt = skb_rtable(skb);
868 struct in_device *in_dev;
869 struct inet_peer *peer;
870 struct net *net;
871 int log_martians;
872 int vif;
873
874 rcu_read_lock();
875 in_dev = __in_dev_get_rcu(rt->dst.dev);
876 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
877 rcu_read_unlock();
878 return;
879 }
880 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
881 vif = l3mdev_master_ifindex_rcu(rt->dst.dev);
882 rcu_read_unlock();
883
884 net = dev_net(rt->dst.dev);
885 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, vif, 1);
886 if (!peer) {
887 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST,
888 rt_nexthop(rt, ip_hdr(skb)->daddr));
889 return;
890 }
891
892
893
894
895 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
896 peer->rate_tokens = 0;
897
898
899
900
901 if (peer->rate_tokens >= ip_rt_redirect_number) {
902 peer->rate_last = jiffies;
903 goto out_put_peer;
904 }
905
906
907
908
909 if (peer->rate_tokens == 0 ||
910 time_after(jiffies,
911 (peer->rate_last +
912 (ip_rt_redirect_load << peer->rate_tokens)))) {
913 __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr);
914
915 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw);
916 peer->rate_last = jiffies;
917 ++peer->rate_tokens;
918#ifdef CONFIG_IP_ROUTE_VERBOSE
919 if (log_martians &&
920 peer->rate_tokens == ip_rt_redirect_number)
921 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
922 &ip_hdr(skb)->saddr, inet_iif(skb),
923 &ip_hdr(skb)->daddr, &gw);
924#endif
925 }
926out_put_peer:
927 inet_putpeer(peer);
928}
929
930static int ip_error(struct sk_buff *skb)
931{
932 struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
933 struct rtable *rt = skb_rtable(skb);
934 struct inet_peer *peer;
935 unsigned long now;
936 struct net *net;
937 bool send;
938 int code;
939
940
941 if (!in_dev)
942 goto out;
943
944 net = dev_net(rt->dst.dev);
945 if (!IN_DEV_FORWARD(in_dev)) {
946 switch (rt->dst.error) {
947 case EHOSTUNREACH:
948 __IP_INC_STATS(net, IPSTATS_MIB_INADDRERRORS);
949 break;
950
951 case ENETUNREACH:
952 __IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES);
953 break;
954 }
955 goto out;
956 }
957
958 switch (rt->dst.error) {
959 case EINVAL:
960 default:
961 goto out;
962 case EHOSTUNREACH:
963 code = ICMP_HOST_UNREACH;
964 break;
965 case ENETUNREACH:
966 code = ICMP_NET_UNREACH;
967 __IP_INC_STATS(net, IPSTATS_MIB_INNOROUTES);
968 break;
969 case EACCES:
970 code = ICMP_PKT_FILTERED;
971 break;
972 }
973
974 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr,
975 l3mdev_master_ifindex(skb->dev), 1);
976
977 send = true;
978 if (peer) {
979 now = jiffies;
980 peer->rate_tokens += now - peer->rate_last;
981 if (peer->rate_tokens > ip_rt_error_burst)
982 peer->rate_tokens = ip_rt_error_burst;
983 peer->rate_last = now;
984 if (peer->rate_tokens >= ip_rt_error_cost)
985 peer->rate_tokens -= ip_rt_error_cost;
986 else
987 send = false;
988 inet_putpeer(peer);
989 }
990 if (send)
991 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
992
993out: kfree_skb(skb);
994 return 0;
995}
996
997static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
998{
999 struct dst_entry *dst = &rt->dst;
1000 struct fib_result res;
1001
1002 if (dst_metric_locked(dst, RTAX_MTU))
1003 return;
1004
1005 if (ipv4_mtu(dst) < mtu)
1006 return;
1007
1008 if (mtu < ip_rt_min_pmtu)
1009 mtu = ip_rt_min_pmtu;
1010
1011 if (rt->rt_pmtu == mtu &&
1012 time_before(jiffies, dst->expires - ip_rt_mtu_expires / 2))
1013 return;
1014
1015 rcu_read_lock();
1016 if (fib_lookup(dev_net(dst->dev), fl4, &res, 0) == 0) {
1017 struct fib_nh *nh = &FIB_RES_NH(res);
1018
1019 update_or_create_fnhe(nh, fl4->daddr, 0, mtu,
1020 jiffies + ip_rt_mtu_expires);
1021 }
1022 rcu_read_unlock();
1023}
1024
1025static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1026 struct sk_buff *skb, u32 mtu)
1027{
1028 struct rtable *rt = (struct rtable *) dst;
1029 struct flowi4 fl4;
1030
1031 ip_rt_build_flow_key(&fl4, sk, skb);
1032 __ip_rt_update_pmtu(rt, &fl4, mtu);
1033}
1034
1035void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
1036 int oif, u32 mark, u8 protocol, int flow_flags)
1037{
1038 const struct iphdr *iph = (const struct iphdr *) skb->data;
1039 struct flowi4 fl4;
1040 struct rtable *rt;
1041
1042 if (!mark)
1043 mark = IP4_REPLY_MARK(net, skb->mark);
1044
1045 __build_flow_key(net, &fl4, NULL, iph, oif,
1046 RT_TOS(iph->tos), protocol, mark, flow_flags);
1047 rt = __ip_route_output_key(net, &fl4);
1048 if (!IS_ERR(rt)) {
1049 __ip_rt_update_pmtu(rt, &fl4, mtu);
1050 ip_rt_put(rt);
1051 }
1052}
1053EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
1054
1055static void __ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
1056{
1057 const struct iphdr *iph = (const struct iphdr *) skb->data;
1058 struct flowi4 fl4;
1059 struct rtable *rt;
1060
1061 __build_flow_key(sock_net(sk), &fl4, sk, iph, 0, 0, 0, 0, 0);
1062
1063 if (!fl4.flowi4_mark)
1064 fl4.flowi4_mark = IP4_REPLY_MARK(sock_net(sk), skb->mark);
1065
1066 rt = __ip_route_output_key(sock_net(sk), &fl4);
1067 if (!IS_ERR(rt)) {
1068 __ip_rt_update_pmtu(rt, &fl4, mtu);
1069 ip_rt_put(rt);
1070 }
1071}
1072
1073void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
1074{
1075 const struct iphdr *iph = (const struct iphdr *) skb->data;
1076 struct flowi4 fl4;
1077 struct rtable *rt;
1078 struct dst_entry *odst = NULL;
1079 bool new = false;
1080 struct net *net = sock_net(sk);
1081
1082 bh_lock_sock(sk);
1083
1084 if (!ip_sk_accept_pmtu(sk))
1085 goto out;
1086
1087 odst = sk_dst_get(sk);
1088
1089 if (sock_owned_by_user(sk) || !odst) {
1090 __ipv4_sk_update_pmtu(skb, sk, mtu);
1091 goto out;
1092 }
1093
1094 __build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0);
1095
1096 rt = (struct rtable *)odst;
1097 if (odst->obsolete && !odst->ops->check(odst, 0)) {
1098 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
1099 if (IS_ERR(rt))
1100 goto out;
1101
1102 new = true;
1103 }
1104
1105 __ip_rt_update_pmtu((struct rtable *) rt->dst.path, &fl4, mtu);
1106
1107 if (!dst_check(&rt->dst, 0)) {
1108 if (new)
1109 dst_release(&rt->dst);
1110
1111 rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
1112 if (IS_ERR(rt))
1113 goto out;
1114
1115 new = true;
1116 }
1117
1118 if (new)
1119 sk_dst_set(sk, &rt->dst);
1120
1121out:
1122 bh_unlock_sock(sk);
1123 dst_release(odst);
1124}
1125EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
1126
1127void ipv4_redirect(struct sk_buff *skb, struct net *net,
1128 int oif, u32 mark, u8 protocol, int flow_flags)
1129{
1130 const struct iphdr *iph = (const struct iphdr *) skb->data;
1131 struct flowi4 fl4;
1132 struct rtable *rt;
1133
1134 __build_flow_key(net, &fl4, NULL, iph, oif,
1135 RT_TOS(iph->tos), protocol, mark, flow_flags);
1136 rt = __ip_route_output_key(net, &fl4);
1137 if (!IS_ERR(rt)) {
1138 __ip_do_redirect(rt, skb, &fl4, false);
1139 ip_rt_put(rt);
1140 }
1141}
1142EXPORT_SYMBOL_GPL(ipv4_redirect);
1143
1144void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
1145{
1146 const struct iphdr *iph = (const struct iphdr *) skb->data;
1147 struct flowi4 fl4;
1148 struct rtable *rt;
1149 struct net *net = sock_net(sk);
1150
1151 __build_flow_key(net, &fl4, sk, iph, 0, 0, 0, 0, 0);
1152 rt = __ip_route_output_key(net, &fl4);
1153 if (!IS_ERR(rt)) {
1154 __ip_do_redirect(rt, skb, &fl4, false);
1155 ip_rt_put(rt);
1156 }
1157}
1158EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1159
1160static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1161{
1162 struct rtable *rt = (struct rtable *) dst;
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172 if (dst->obsolete != DST_OBSOLETE_FORCE_CHK || rt_is_expired(rt))
1173 return NULL;
1174 return dst;
1175}
1176
1177static void ipv4_link_failure(struct sk_buff *skb)
1178{
1179 struct rtable *rt;
1180
1181 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1182
1183 rt = skb_rtable(skb);
1184 if (rt)
1185 dst_set_expires(&rt->dst, 0);
1186}
1187
1188static int ip_rt_bug(struct net *net, struct sock *sk, struct sk_buff *skb)
1189{
1190 pr_debug("%s: %pI4 -> %pI4, %s\n",
1191 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1192 skb->dev ? skb->dev->name : "?");
1193 kfree_skb(skb);
1194 WARN_ON(1);
1195 return 0;
1196}
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
1208{
1209 __be32 src;
1210
1211 if (rt_is_output_route(rt))
1212 src = ip_hdr(skb)->saddr;
1213 else {
1214 struct fib_result res;
1215 struct flowi4 fl4;
1216 struct iphdr *iph;
1217
1218 iph = ip_hdr(skb);
1219
1220 memset(&fl4, 0, sizeof(fl4));
1221 fl4.daddr = iph->daddr;
1222 fl4.saddr = iph->saddr;
1223 fl4.flowi4_tos = RT_TOS(iph->tos);
1224 fl4.flowi4_oif = rt->dst.dev->ifindex;
1225 fl4.flowi4_iif = skb->dev->ifindex;
1226 fl4.flowi4_mark = skb->mark;
1227
1228 rcu_read_lock();
1229 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0)
1230 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
1231 else
1232 src = inet_select_addr(rt->dst.dev,
1233 rt_nexthop(rt, iph->daddr),
1234 RT_SCOPE_UNIVERSE);
1235 rcu_read_unlock();
1236 }
1237 memcpy(addr, &src, 4);
1238}
1239
1240#ifdef CONFIG_IP_ROUTE_CLASSID
1241static void set_class_tag(struct rtable *rt, u32 tag)
1242{
1243 if (!(rt->dst.tclassid & 0xFFFF))
1244 rt->dst.tclassid |= tag & 0xFFFF;
1245 if (!(rt->dst.tclassid & 0xFFFF0000))
1246 rt->dst.tclassid |= tag & 0xFFFF0000;
1247}
1248#endif
1249
1250static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1251{
1252 unsigned int header_size = sizeof(struct tcphdr) + sizeof(struct iphdr);
1253 unsigned int advmss = max_t(unsigned int, dst->dev->mtu - header_size,
1254 ip_rt_min_advmss);
1255
1256 return min(advmss, IPV4_MAX_PMTU - header_size);
1257}
1258
1259static unsigned int ipv4_mtu(const struct dst_entry *dst)
1260{
1261 const struct rtable *rt = (const struct rtable *) dst;
1262 unsigned int mtu = rt->rt_pmtu;
1263
1264 if (!mtu || time_after_eq(jiffies, rt->dst.expires))
1265 mtu = dst_metric_raw(dst, RTAX_MTU);
1266
1267 if (mtu)
1268 return mtu;
1269
1270 mtu = READ_ONCE(dst->dev->mtu);
1271
1272 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
1273 if (rt->rt_uses_gateway && mtu > 576)
1274 mtu = 576;
1275 }
1276
1277 mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
1278
1279 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
1280}
1281
1282static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
1283{
1284 struct fnhe_hash_bucket *hash = rcu_dereference(nh->nh_exceptions);
1285 struct fib_nh_exception *fnhe;
1286 u32 hval;
1287
1288 if (!hash)
1289 return NULL;
1290
1291 hval = fnhe_hashfun(daddr);
1292
1293 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1294 fnhe = rcu_dereference(fnhe->fnhe_next)) {
1295 if (fnhe->fnhe_daddr == daddr)
1296 return fnhe;
1297 }
1298 return NULL;
1299}
1300
1301static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
1302 __be32 daddr, const bool do_cache)
1303{
1304 bool ret = false;
1305
1306 spin_lock_bh(&fnhe_lock);
1307
1308 if (daddr == fnhe->fnhe_daddr) {
1309 struct rtable __rcu **porig;
1310 struct rtable *orig;
1311 int genid = fnhe_genid(dev_net(rt->dst.dev));
1312
1313 if (rt_is_input_route(rt))
1314 porig = &fnhe->fnhe_rth_input;
1315 else
1316 porig = &fnhe->fnhe_rth_output;
1317 orig = rcu_dereference(*porig);
1318
1319 if (fnhe->fnhe_genid != genid) {
1320 fnhe->fnhe_genid = genid;
1321 fnhe->fnhe_gw = 0;
1322 fnhe->fnhe_pmtu = 0;
1323 fnhe->fnhe_expires = 0;
1324 fnhe_flush_routes(fnhe);
1325 orig = NULL;
1326 }
1327 fill_route_from_fnhe(rt, fnhe);
1328 if (!rt->rt_gateway)
1329 rt->rt_gateway = daddr;
1330
1331 if (do_cache) {
1332 dst_hold(&rt->dst);
1333 rcu_assign_pointer(*porig, rt);
1334 if (orig) {
1335 dst_dev_put(&orig->dst);
1336 dst_release(&orig->dst);
1337 }
1338 ret = true;
1339 }
1340
1341 fnhe->fnhe_stamp = jiffies;
1342 }
1343 spin_unlock_bh(&fnhe_lock);
1344
1345 return ret;
1346}
1347
1348static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt)
1349{
1350 struct rtable *orig, *prev, **p;
1351 bool ret = true;
1352
1353 if (rt_is_input_route(rt)) {
1354 p = (struct rtable **)&nh->nh_rth_input;
1355 } else {
1356 p = (struct rtable **)raw_cpu_ptr(nh->nh_pcpu_rth_output);
1357 }
1358 orig = *p;
1359
1360
1361
1362
1363 dst_hold(&rt->dst);
1364 prev = cmpxchg(p, orig, rt);
1365 if (prev == orig) {
1366 if (orig) {
1367 dst_dev_put(&orig->dst);
1368 dst_release(&orig->dst);
1369 }
1370 } else {
1371 dst_release(&rt->dst);
1372 ret = false;
1373 }
1374
1375 return ret;
1376}
1377
1378struct uncached_list {
1379 spinlock_t lock;
1380 struct list_head head;
1381};
1382
1383static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt_uncached_list);
1384
1385static void rt_add_uncached_list(struct rtable *rt)
1386{
1387 struct uncached_list *ul = raw_cpu_ptr(&rt_uncached_list);
1388
1389 rt->rt_uncached_list = ul;
1390
1391 spin_lock_bh(&ul->lock);
1392 list_add_tail(&rt->rt_uncached, &ul->head);
1393 spin_unlock_bh(&ul->lock);
1394}
1395
1396static void ipv4_dst_destroy(struct dst_entry *dst)
1397{
1398 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst);
1399 struct rtable *rt = (struct rtable *) dst;
1400
1401 if (p != &dst_default_metrics && atomic_dec_and_test(&p->refcnt))
1402 kfree(p);
1403
1404 if (!list_empty(&rt->rt_uncached)) {
1405 struct uncached_list *ul = rt->rt_uncached_list;
1406
1407 spin_lock_bh(&ul->lock);
1408 list_del(&rt->rt_uncached);
1409 spin_unlock_bh(&ul->lock);
1410 }
1411}
1412
1413void rt_flush_dev(struct net_device *dev)
1414{
1415 struct net *net = dev_net(dev);
1416 struct rtable *rt;
1417 int cpu;
1418
1419 for_each_possible_cpu(cpu) {
1420 struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
1421
1422 spin_lock_bh(&ul->lock);
1423 list_for_each_entry(rt, &ul->head, rt_uncached) {
1424 if (rt->dst.dev != dev)
1425 continue;
1426 rt->dst.dev = net->loopback_dev;
1427 dev_hold(rt->dst.dev);
1428 dev_put(dev);
1429 }
1430 spin_unlock_bh(&ul->lock);
1431 }
1432}
1433
1434static bool rt_cache_valid(const struct rtable *rt)
1435{
1436 return rt &&
1437 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1438 !rt_is_expired(rt);
1439}
1440
1441static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
1442 const struct fib_result *res,
1443 struct fib_nh_exception *fnhe,
1444 struct fib_info *fi, u16 type, u32 itag,
1445 const bool do_cache)
1446{
1447 bool cached = false;
1448
1449 if (fi) {
1450 struct fib_nh *nh = &FIB_RES_NH(*res);
1451
1452 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) {
1453 rt->rt_gateway = nh->nh_gw;
1454 rt->rt_uses_gateway = 1;
1455 }
1456 dst_init_metrics(&rt->dst, fi->fib_metrics->metrics, true);
1457 if (fi->fib_metrics != &dst_default_metrics) {
1458 rt->dst._metrics |= DST_METRICS_REFCOUNTED;
1459 atomic_inc(&fi->fib_metrics->refcnt);
1460 }
1461#ifdef CONFIG_IP_ROUTE_CLASSID
1462 rt->dst.tclassid = nh->nh_tclassid;
1463#endif
1464 rt->dst.lwtstate = lwtstate_get(nh->nh_lwtstate);
1465 if (unlikely(fnhe))
1466 cached = rt_bind_exception(rt, fnhe, daddr, do_cache);
1467 else if (do_cache)
1468 cached = rt_cache_route(nh, rt);
1469 if (unlikely(!cached)) {
1470
1471
1472
1473
1474
1475 if (!rt->rt_gateway)
1476 rt->rt_gateway = daddr;
1477 rt_add_uncached_list(rt);
1478 }
1479 } else
1480 rt_add_uncached_list(rt);
1481
1482#ifdef CONFIG_IP_ROUTE_CLASSID
1483#ifdef CONFIG_IP_MULTIPLE_TABLES
1484 set_class_tag(rt, res->tclassid);
1485#endif
1486 set_class_tag(rt, itag);
1487#endif
1488}
1489
1490struct rtable *rt_dst_alloc(struct net_device *dev,
1491 unsigned int flags, u16 type,
1492 bool nopolicy, bool noxfrm, bool will_cache)
1493{
1494 struct rtable *rt;
1495
1496 rt = dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
1497 (will_cache ? 0 : DST_HOST) |
1498 (nopolicy ? DST_NOPOLICY : 0) |
1499 (noxfrm ? DST_NOXFRM : 0));
1500
1501 if (rt) {
1502 rt->rt_genid = rt_genid_ipv4(dev_net(dev));
1503 rt->rt_flags = flags;
1504 rt->rt_type = type;
1505 rt->rt_is_input = 0;
1506 rt->rt_iif = 0;
1507 rt->rt_pmtu = 0;
1508 rt->rt_gateway = 0;
1509 rt->rt_uses_gateway = 0;
1510 rt->rt_table_id = 0;
1511 INIT_LIST_HEAD(&rt->rt_uncached);
1512
1513 rt->dst.output = ip_output;
1514 if (flags & RTCF_LOCAL)
1515 rt->dst.input = ip_local_deliver;
1516 }
1517
1518 return rt;
1519}
1520EXPORT_SYMBOL(rt_dst_alloc);
1521
1522
1523static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1524 u8 tos, struct net_device *dev, int our)
1525{
1526 struct rtable *rth;
1527 struct in_device *in_dev = __in_dev_get_rcu(dev);
1528 unsigned int flags = RTCF_MULTICAST;
1529 u32 itag = 0;
1530 int err;
1531
1532
1533
1534 if (!in_dev)
1535 return -EINVAL;
1536
1537 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1538 skb->protocol != htons(ETH_P_IP))
1539 goto e_inval;
1540
1541 if (ipv4_is_loopback(saddr) && !IN_DEV_ROUTE_LOCALNET(in_dev))
1542 goto e_inval;
1543
1544 if (ipv4_is_zeronet(saddr)) {
1545 if (!ipv4_is_local_multicast(daddr))
1546 goto e_inval;
1547 } else {
1548 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1549 in_dev, &itag);
1550 if (err < 0)
1551 goto e_err;
1552 }
1553 if (our)
1554 flags |= RTCF_LOCAL;
1555
1556 rth = rt_dst_alloc(dev_net(dev)->loopback_dev, flags, RTN_MULTICAST,
1557 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false);
1558 if (!rth)
1559 goto e_nobufs;
1560
1561#ifdef CONFIG_IP_ROUTE_CLASSID
1562 rth->dst.tclassid = itag;
1563#endif
1564 rth->dst.output = ip_rt_bug;
1565 rth->rt_is_input= 1;
1566
1567#ifdef CONFIG_IP_MROUTE
1568 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1569 rth->dst.input = ip_mr_input;
1570#endif
1571 RT_CACHE_STAT_INC(in_slow_mc);
1572
1573 skb_dst_set(skb, &rth->dst);
1574 return 0;
1575
1576e_nobufs:
1577 return -ENOBUFS;
1578e_inval:
1579 return -EINVAL;
1580e_err:
1581 return err;
1582}
1583
1584
1585static void ip_handle_martian_source(struct net_device *dev,
1586 struct in_device *in_dev,
1587 struct sk_buff *skb,
1588 __be32 daddr,
1589 __be32 saddr)
1590{
1591 RT_CACHE_STAT_INC(in_martian_src);
1592#ifdef CONFIG_IP_ROUTE_VERBOSE
1593 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1594
1595
1596
1597
1598 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
1599 &daddr, &saddr, dev->name);
1600 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1601 print_hex_dump(KERN_WARNING, "ll header: ",
1602 DUMP_PREFIX_OFFSET, 16, 1,
1603 skb_mac_header(skb),
1604 dev->hard_header_len, true);
1605 }
1606 }
1607#endif
1608}
1609
1610static void ip_del_fnhe(struct fib_nh *nh, __be32 daddr)
1611{
1612 struct fnhe_hash_bucket *hash;
1613 struct fib_nh_exception *fnhe, __rcu **fnhe_p;
1614 u32 hval = fnhe_hashfun(daddr);
1615
1616 spin_lock_bh(&fnhe_lock);
1617
1618 hash = rcu_dereference_protected(nh->nh_exceptions,
1619 lockdep_is_held(&fnhe_lock));
1620 hash += hval;
1621
1622 fnhe_p = &hash->chain;
1623 fnhe = rcu_dereference_protected(*fnhe_p, lockdep_is_held(&fnhe_lock));
1624 while (fnhe) {
1625 if (fnhe->fnhe_daddr == daddr) {
1626 rcu_assign_pointer(*fnhe_p, rcu_dereference_protected(
1627 fnhe->fnhe_next, lockdep_is_held(&fnhe_lock)));
1628 fnhe_flush_routes(fnhe);
1629 kfree_rcu(fnhe, rcu);
1630 break;
1631 }
1632 fnhe_p = &fnhe->fnhe_next;
1633 fnhe = rcu_dereference_protected(fnhe->fnhe_next,
1634 lockdep_is_held(&fnhe_lock));
1635 }
1636
1637 spin_unlock_bh(&fnhe_lock);
1638}
1639
1640static void set_lwt_redirect(struct rtable *rth)
1641{
1642 if (lwtunnel_output_redirect(rth->dst.lwtstate)) {
1643 rth->dst.lwtstate->orig_output = rth->dst.output;
1644 rth->dst.output = lwtunnel_output;
1645 }
1646
1647 if (lwtunnel_input_redirect(rth->dst.lwtstate)) {
1648 rth->dst.lwtstate->orig_input = rth->dst.input;
1649 rth->dst.input = lwtunnel_input;
1650 }
1651}
1652
1653
1654static int __mkroute_input(struct sk_buff *skb,
1655 const struct fib_result *res,
1656 struct in_device *in_dev,
1657 __be32 daddr, __be32 saddr, u32 tos)
1658{
1659 struct fib_nh_exception *fnhe;
1660 struct rtable *rth;
1661 int err;
1662 struct in_device *out_dev;
1663 bool do_cache;
1664 u32 itag = 0;
1665
1666
1667 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1668 if (!out_dev) {
1669 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
1670 return -EINVAL;
1671 }
1672
1673 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
1674 in_dev->dev, in_dev, &itag);
1675 if (err < 0) {
1676 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1677 saddr);
1678
1679 goto cleanup;
1680 }
1681
1682 do_cache = res->fi && !itag;
1683 if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
1684 skb->protocol == htons(ETH_P_IP) &&
1685 (IN_DEV_SHARED_MEDIA(out_dev) ||
1686 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1687 IPCB(skb)->flags |= IPSKB_DOREDIRECT;
1688
1689 if (skb->protocol != htons(ETH_P_IP)) {
1690
1691
1692
1693
1694
1695
1696
1697 if (out_dev == in_dev &&
1698 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1699 err = -EINVAL;
1700 goto cleanup;
1701 }
1702 }
1703
1704 fnhe = find_exception(&FIB_RES_NH(*res), daddr);
1705 if (do_cache) {
1706 if (fnhe) {
1707 rth = rcu_dereference(fnhe->fnhe_rth_input);
1708 if (rth && rth->dst.expires &&
1709 time_after(jiffies, rth->dst.expires)) {
1710 ip_del_fnhe(&FIB_RES_NH(*res), daddr);
1711 fnhe = NULL;
1712 } else {
1713 goto rt_cache;
1714 }
1715 }
1716
1717 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1718
1719rt_cache:
1720 if (rt_cache_valid(rth)) {
1721 skb_dst_set_noref(skb, &rth->dst);
1722 goto out;
1723 }
1724 }
1725
1726 rth = rt_dst_alloc(out_dev->dev, 0, res->type,
1727 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1728 IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache);
1729 if (!rth) {
1730 err = -ENOBUFS;
1731 goto cleanup;
1732 }
1733
1734 rth->rt_is_input = 1;
1735 if (res->table)
1736 rth->rt_table_id = res->table->tb_id;
1737 RT_CACHE_STAT_INC(in_slow_tot);
1738
1739 rth->dst.input = ip_forward;
1740
1741 rt_set_nexthop(rth, daddr, res, fnhe, res->fi, res->type, itag,
1742 do_cache);
1743 set_lwt_redirect(rth);
1744 skb_dst_set(skb, &rth->dst);
1745out:
1746 err = 0;
1747 cleanup:
1748 return err;
1749}
1750
1751#ifdef CONFIG_IP_ROUTE_MULTIPATH
1752
1753
1754
1755static void ip_multipath_l3_keys(const struct sk_buff *skb,
1756 struct flow_keys *hash_keys)
1757{
1758 const struct iphdr *outer_iph = ip_hdr(skb);
1759 const struct iphdr *inner_iph;
1760 const struct icmphdr *icmph;
1761 struct iphdr _inner_iph;
1762 struct icmphdr _icmph;
1763
1764 hash_keys->addrs.v4addrs.src = outer_iph->saddr;
1765 hash_keys->addrs.v4addrs.dst = outer_iph->daddr;
1766 if (likely(outer_iph->protocol != IPPROTO_ICMP))
1767 return;
1768
1769 if (unlikely((outer_iph->frag_off & htons(IP_OFFSET)) != 0))
1770 return;
1771
1772 icmph = skb_header_pointer(skb, outer_iph->ihl * 4, sizeof(_icmph),
1773 &_icmph);
1774 if (!icmph)
1775 return;
1776
1777 if (icmph->type != ICMP_DEST_UNREACH &&
1778 icmph->type != ICMP_REDIRECT &&
1779 icmph->type != ICMP_TIME_EXCEEDED &&
1780 icmph->type != ICMP_PARAMETERPROB)
1781 return;
1782
1783 inner_iph = skb_header_pointer(skb,
1784 outer_iph->ihl * 4 + sizeof(_icmph),
1785 sizeof(_inner_iph), &_inner_iph);
1786 if (!inner_iph)
1787 return;
1788 hash_keys->addrs.v4addrs.src = inner_iph->saddr;
1789 hash_keys->addrs.v4addrs.dst = inner_iph->daddr;
1790}
1791
1792
1793int fib_multipath_hash(const struct fib_info *fi, const struct flowi4 *fl4,
1794 const struct sk_buff *skb)
1795{
1796 struct net *net = fi->fib_net;
1797 struct flow_keys hash_keys;
1798 u32 mhash;
1799
1800 switch (net->ipv4.sysctl_fib_multipath_hash_policy) {
1801 case 0:
1802 memset(&hash_keys, 0, sizeof(hash_keys));
1803 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1804 if (skb) {
1805 ip_multipath_l3_keys(skb, &hash_keys);
1806 } else {
1807 hash_keys.addrs.v4addrs.src = fl4->saddr;
1808 hash_keys.addrs.v4addrs.dst = fl4->daddr;
1809 }
1810 break;
1811 case 1:
1812
1813 if (skb) {
1814 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
1815 struct flow_keys keys;
1816
1817
1818 if (skb->l4_hash)
1819 return skb_get_hash_raw(skb) >> 1;
1820 memset(&hash_keys, 0, sizeof(hash_keys));
1821 skb_flow_dissect_flow_keys(skb, &keys, flag);
1822 hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src;
1823 hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst;
1824 hash_keys.ports.src = keys.ports.src;
1825 hash_keys.ports.dst = keys.ports.dst;
1826 hash_keys.basic.ip_proto = keys.basic.ip_proto;
1827 } else {
1828 memset(&hash_keys, 0, sizeof(hash_keys));
1829 hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1830 hash_keys.addrs.v4addrs.src = fl4->saddr;
1831 hash_keys.addrs.v4addrs.dst = fl4->daddr;
1832 hash_keys.ports.src = fl4->fl4_sport;
1833 hash_keys.ports.dst = fl4->fl4_dport;
1834 hash_keys.basic.ip_proto = fl4->flowi4_proto;
1835 }
1836 break;
1837 }
1838 mhash = flow_hash_from_keys(&hash_keys);
1839
1840 return mhash >> 1;
1841}
1842EXPORT_SYMBOL_GPL(fib_multipath_hash);
1843#endif
1844
1845static int ip_mkroute_input(struct sk_buff *skb,
1846 struct fib_result *res,
1847 struct in_device *in_dev,
1848 __be32 daddr, __be32 saddr, u32 tos)
1849{
1850#ifdef CONFIG_IP_ROUTE_MULTIPATH
1851 if (res->fi && res->fi->fib_nhs > 1) {
1852 int h = fib_multipath_hash(res->fi, NULL, skb);
1853
1854 fib_select_multipath(res, h);
1855 }
1856#endif
1857
1858
1859 return __mkroute_input(skb, res, in_dev, daddr, saddr, tos);
1860}
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1874 u8 tos, struct net_device *dev,
1875 struct fib_result *res)
1876{
1877 struct in_device *in_dev = __in_dev_get_rcu(dev);
1878 struct ip_tunnel_info *tun_info;
1879 struct flowi4 fl4;
1880 unsigned int flags = 0;
1881 u32 itag = 0;
1882 struct rtable *rth;
1883 int err = -EINVAL;
1884 struct net *net = dev_net(dev);
1885 bool do_cache;
1886
1887
1888
1889 if (!in_dev)
1890 goto out;
1891
1892
1893
1894
1895
1896 tun_info = skb_tunnel_info(skb);
1897 if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1898 fl4.flowi4_tun_key.tun_id = tun_info->key.tun_id;
1899 else
1900 fl4.flowi4_tun_key.tun_id = 0;
1901 skb_dst_drop(skb);
1902
1903 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
1904 goto martian_source;
1905
1906 res->fi = NULL;
1907 res->table = NULL;
1908 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
1909 goto brd_input;
1910
1911
1912
1913
1914 if (ipv4_is_zeronet(saddr))
1915 goto martian_source;
1916
1917 if (ipv4_is_zeronet(daddr))
1918 goto martian_destination;
1919
1920
1921
1922
1923 if (ipv4_is_loopback(daddr)) {
1924 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
1925 goto martian_destination;
1926 } else if (ipv4_is_loopback(saddr)) {
1927 if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
1928 goto martian_source;
1929 }
1930
1931
1932
1933
1934 fl4.flowi4_oif = 0;
1935 fl4.flowi4_iif = dev->ifindex;
1936 fl4.flowi4_mark = skb->mark;
1937 fl4.flowi4_tos = tos;
1938 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
1939 fl4.flowi4_flags = 0;
1940 fl4.daddr = daddr;
1941 fl4.saddr = saddr;
1942 fl4.flowi4_uid = sock_net_uid(net, NULL);
1943 err = fib_lookup(net, &fl4, res, 0);
1944 if (err != 0) {
1945 if (!IN_DEV_FORWARD(in_dev))
1946 err = -EHOSTUNREACH;
1947 goto no_route;
1948 }
1949
1950 if (res->type == RTN_BROADCAST)
1951 goto brd_input;
1952
1953 if (res->type == RTN_LOCAL) {
1954 err = fib_validate_source(skb, saddr, daddr, tos,
1955 0, dev, in_dev, &itag);
1956 if (err < 0)
1957 goto martian_source;
1958 goto local_input;
1959 }
1960
1961 if (!IN_DEV_FORWARD(in_dev)) {
1962 err = -EHOSTUNREACH;
1963 goto no_route;
1964 }
1965 if (res->type != RTN_UNICAST)
1966 goto martian_destination;
1967
1968 err = ip_mkroute_input(skb, res, in_dev, daddr, saddr, tos);
1969out: return err;
1970
1971brd_input:
1972 if (skb->protocol != htons(ETH_P_IP))
1973 goto e_inval;
1974
1975 if (!ipv4_is_zeronet(saddr)) {
1976 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1977 in_dev, &itag);
1978 if (err < 0)
1979 goto martian_source;
1980 }
1981 flags |= RTCF_BROADCAST;
1982 res->type = RTN_BROADCAST;
1983 RT_CACHE_STAT_INC(in_brd);
1984
1985local_input:
1986 do_cache = false;
1987 if (res->fi) {
1988 if (!itag) {
1989 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1990 if (rt_cache_valid(rth)) {
1991 skb_dst_set_noref(skb, &rth->dst);
1992 err = 0;
1993 goto out;
1994 }
1995 do_cache = true;
1996 }
1997 }
1998
1999 rth = rt_dst_alloc(l3mdev_master_dev_rcu(dev) ? : net->loopback_dev,
2000 flags | RTCF_LOCAL, res->type,
2001 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache);
2002 if (!rth)
2003 goto e_nobufs;
2004
2005 rth->dst.output= ip_rt_bug;
2006#ifdef CONFIG_IP_ROUTE_CLASSID
2007 rth->dst.tclassid = itag;
2008#endif
2009 rth->rt_is_input = 1;
2010 if (res->table)
2011 rth->rt_table_id = res->table->tb_id;
2012
2013 RT_CACHE_STAT_INC(in_slow_tot);
2014 if (res->type == RTN_UNREACHABLE) {
2015 rth->dst.input= ip_error;
2016 rth->dst.error= -err;
2017 rth->rt_flags &= ~RTCF_LOCAL;
2018 }
2019
2020 if (do_cache) {
2021 struct fib_nh *nh = &FIB_RES_NH(*res);
2022
2023 rth->dst.lwtstate = lwtstate_get(nh->nh_lwtstate);
2024 if (lwtunnel_input_redirect(rth->dst.lwtstate)) {
2025 WARN_ON(rth->dst.input == lwtunnel_input);
2026 rth->dst.lwtstate->orig_input = rth->dst.input;
2027 rth->dst.input = lwtunnel_input;
2028 }
2029
2030 if (unlikely(!rt_cache_route(nh, rth)))
2031 rt_add_uncached_list(rth);
2032 }
2033 skb_dst_set(skb, &rth->dst);
2034 err = 0;
2035 goto out;
2036
2037no_route:
2038 RT_CACHE_STAT_INC(in_no_route);
2039 res->type = RTN_UNREACHABLE;
2040 res->fi = NULL;
2041 res->table = NULL;
2042 goto local_input;
2043
2044
2045
2046
2047martian_destination:
2048 RT_CACHE_STAT_INC(in_martian_dst);
2049#ifdef CONFIG_IP_ROUTE_VERBOSE
2050 if (IN_DEV_LOG_MARTIANS(in_dev))
2051 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
2052 &daddr, &saddr, dev->name);
2053#endif
2054
2055e_inval:
2056 err = -EINVAL;
2057 goto out;
2058
2059e_nobufs:
2060 err = -ENOBUFS;
2061 goto out;
2062
2063martian_source:
2064 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
2065 goto out;
2066}
2067
2068int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2069 u8 tos, struct net_device *dev)
2070{
2071 struct fib_result res;
2072 int err;
2073
2074 tos &= IPTOS_RT_MASK;
2075 rcu_read_lock();
2076 err = ip_route_input_rcu(skb, daddr, saddr, tos, dev, &res);
2077 rcu_read_unlock();
2078
2079 return err;
2080}
2081EXPORT_SYMBOL(ip_route_input_noref);
2082
2083
2084int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2085 u8 tos, struct net_device *dev, struct fib_result *res)
2086{
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098 if (ipv4_is_multicast(daddr)) {
2099 struct in_device *in_dev = __in_dev_get_rcu(dev);
2100 int our = 0;
2101 int err = -EINVAL;
2102
2103 if (in_dev)
2104 our = ip_check_mc_rcu(in_dev, daddr, saddr,
2105 ip_hdr(skb)->protocol);
2106
2107
2108 if ((!in_dev || !our) && netif_is_l3_slave(dev)) {
2109 struct in_device *l3_in_dev;
2110
2111 l3_in_dev = __in_dev_get_rcu(skb->dev);
2112 if (l3_in_dev)
2113 our = ip_check_mc_rcu(l3_in_dev, daddr, saddr,
2114 ip_hdr(skb)->protocol);
2115 }
2116
2117 if (our
2118#ifdef CONFIG_IP_MROUTE
2119 ||
2120 (!ipv4_is_local_multicast(daddr) &&
2121 IN_DEV_MFORWARD(in_dev))
2122#endif
2123 ) {
2124 err = ip_route_input_mc(skb, daddr, saddr,
2125 tos, dev, our);
2126 }
2127 return err;
2128 }
2129
2130 return ip_route_input_slow(skb, daddr, saddr, tos, dev, res);
2131}
2132
2133
2134static struct rtable *__mkroute_output(const struct fib_result *res,
2135 const struct flowi4 *fl4, int orig_oif,
2136 struct net_device *dev_out,
2137 unsigned int flags)
2138{
2139 struct fib_info *fi = res->fi;
2140 struct fib_nh_exception *fnhe;
2141 struct in_device *in_dev;
2142 u16 type = res->type;
2143 struct rtable *rth;
2144 bool do_cache;
2145
2146 in_dev = __in_dev_get_rcu(dev_out);
2147 if (!in_dev)
2148 return ERR_PTR(-EINVAL);
2149
2150 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
2151 if (ipv4_is_loopback(fl4->saddr) &&
2152 !(dev_out->flags & IFF_LOOPBACK) &&
2153 !netif_is_l3_master(dev_out))
2154 return ERR_PTR(-EINVAL);
2155
2156 if (ipv4_is_lbcast(fl4->daddr))
2157 type = RTN_BROADCAST;
2158 else if (ipv4_is_multicast(fl4->daddr))
2159 type = RTN_MULTICAST;
2160 else if (ipv4_is_zeronet(fl4->daddr))
2161 return ERR_PTR(-EINVAL);
2162
2163 if (dev_out->flags & IFF_LOOPBACK)
2164 flags |= RTCF_LOCAL;
2165
2166 do_cache = true;
2167 if (type == RTN_BROADCAST) {
2168 flags |= RTCF_BROADCAST | RTCF_LOCAL;
2169 fi = NULL;
2170 } else if (type == RTN_MULTICAST) {
2171 flags |= RTCF_MULTICAST | RTCF_LOCAL;
2172 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
2173 fl4->flowi4_proto))
2174 flags &= ~RTCF_LOCAL;
2175 else
2176 do_cache = false;
2177
2178
2179
2180
2181 if (fi && res->prefixlen < 4)
2182 fi = NULL;
2183 } else if ((type == RTN_LOCAL) && (orig_oif != 0) &&
2184 (orig_oif != dev_out->ifindex)) {
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194 fi = NULL;
2195 }
2196
2197 fnhe = NULL;
2198 do_cache &= fi != NULL;
2199 if (do_cache) {
2200 struct rtable __rcu **prth;
2201 struct fib_nh *nh = &FIB_RES_NH(*res);
2202
2203 fnhe = find_exception(nh, fl4->daddr);
2204 if (fnhe) {
2205 prth = &fnhe->fnhe_rth_output;
2206 rth = rcu_dereference(*prth);
2207 if (rth && rth->dst.expires &&
2208 time_after(jiffies, rth->dst.expires)) {
2209 ip_del_fnhe(nh, fl4->daddr);
2210 fnhe = NULL;
2211 } else {
2212 goto rt_cache;
2213 }
2214 }
2215
2216 if (unlikely(fl4->flowi4_flags &
2217 FLOWI_FLAG_KNOWN_NH &&
2218 !(nh->nh_gw &&
2219 nh->nh_scope == RT_SCOPE_LINK))) {
2220 do_cache = false;
2221 goto add;
2222 }
2223 prth = raw_cpu_ptr(nh->nh_pcpu_rth_output);
2224 rth = rcu_dereference(*prth);
2225
2226rt_cache:
2227 if (rt_cache_valid(rth) && dst_hold_safe(&rth->dst))
2228 return rth;
2229 }
2230
2231add:
2232 rth = rt_dst_alloc(dev_out, flags, type,
2233 IN_DEV_CONF_GET(in_dev, NOPOLICY),
2234 IN_DEV_CONF_GET(in_dev, NOXFRM),
2235 do_cache);
2236 if (!rth)
2237 return ERR_PTR(-ENOBUFS);
2238
2239 rth->rt_iif = orig_oif ? : 0;
2240 if (res->table)
2241 rth->rt_table_id = res->table->tb_id;
2242
2243 RT_CACHE_STAT_INC(out_slow_tot);
2244
2245 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
2246 if (flags & RTCF_LOCAL &&
2247 !(dev_out->flags & IFF_LOOPBACK)) {
2248 rth->dst.output = ip_mc_output;
2249 RT_CACHE_STAT_INC(out_slow_mc);
2250 }
2251#ifdef CONFIG_IP_MROUTE
2252 if (type == RTN_MULTICAST) {
2253 if (IN_DEV_MFORWARD(in_dev) &&
2254 !ipv4_is_local_multicast(fl4->daddr)) {
2255 rth->dst.input = ip_mr_input;
2256 rth->dst.output = ip_mc_output;
2257 }
2258 }
2259#endif
2260 }
2261
2262 rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0, do_cache);
2263 set_lwt_redirect(rth);
2264
2265 return rth;
2266}
2267
2268
2269
2270
2271
2272struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
2273 const struct sk_buff *skb)
2274{
2275 __u8 tos = RT_FL_TOS(fl4);
2276 struct fib_result res;
2277 struct rtable *rth;
2278
2279 res.tclassid = 0;
2280 res.fi = NULL;
2281 res.table = NULL;
2282
2283 fl4->flowi4_iif = LOOPBACK_IFINDEX;
2284 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
2285 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
2286 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
2287
2288 rcu_read_lock();
2289 rth = ip_route_output_key_hash_rcu(net, fl4, &res, skb);
2290 rcu_read_unlock();
2291
2292 return rth;
2293}
2294EXPORT_SYMBOL_GPL(ip_route_output_key_hash);
2295
2296struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4 *fl4,
2297 struct fib_result *res,
2298 const struct sk_buff *skb)
2299{
2300 struct net_device *dev_out = NULL;
2301 int orig_oif = fl4->flowi4_oif;
2302 unsigned int flags = 0;
2303 struct rtable *rth;
2304 int err = -ENETUNREACH;
2305
2306 if (fl4->saddr) {
2307 rth = ERR_PTR(-EINVAL);
2308 if (ipv4_is_multicast(fl4->saddr) ||
2309 ipv4_is_lbcast(fl4->saddr) ||
2310 ipv4_is_zeronet(fl4->saddr))
2311 goto out;
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321 if (fl4->flowi4_oif == 0 &&
2322 (ipv4_is_multicast(fl4->daddr) ||
2323 ipv4_is_lbcast(fl4->daddr))) {
2324
2325 dev_out = __ip_dev_find(net, fl4->saddr, false);
2326 if (!dev_out)
2327 goto out;
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344 fl4->flowi4_oif = dev_out->ifindex;
2345 goto make_route;
2346 }
2347
2348 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
2349
2350 if (!__ip_dev_find(net, fl4->saddr, false))
2351 goto out;
2352 }
2353 }
2354
2355
2356 if (fl4->flowi4_oif) {
2357 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
2358 rth = ERR_PTR(-ENODEV);
2359 if (!dev_out)
2360 goto out;
2361
2362
2363 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
2364 rth = ERR_PTR(-ENETUNREACH);
2365 goto out;
2366 }
2367 if (ipv4_is_local_multicast(fl4->daddr) ||
2368 ipv4_is_lbcast(fl4->daddr) ||
2369 fl4->flowi4_proto == IPPROTO_IGMP) {
2370 if (!fl4->saddr)
2371 fl4->saddr = inet_select_addr(dev_out, 0,
2372 RT_SCOPE_LINK);
2373 goto make_route;
2374 }
2375 if (!fl4->saddr) {
2376 if (ipv4_is_multicast(fl4->daddr))
2377 fl4->saddr = inet_select_addr(dev_out, 0,
2378 fl4->flowi4_scope);
2379 else if (!fl4->daddr)
2380 fl4->saddr = inet_select_addr(dev_out, 0,
2381 RT_SCOPE_HOST);
2382 }
2383 }
2384
2385 if (!fl4->daddr) {
2386 fl4->daddr = fl4->saddr;
2387 if (!fl4->daddr)
2388 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
2389 dev_out = net->loopback_dev;
2390 fl4->flowi4_oif = LOOPBACK_IFINDEX;
2391 res->type = RTN_LOCAL;
2392 flags |= RTCF_LOCAL;
2393 goto make_route;
2394 }
2395
2396 err = fib_lookup(net, fl4, res, 0);
2397 if (err) {
2398 res->fi = NULL;
2399 res->table = NULL;
2400 if (fl4->flowi4_oif &&
2401 (ipv4_is_multicast(fl4->daddr) ||
2402 !netif_index_is_l3_master(net, fl4->flowi4_oif))) {
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421 if (fl4->saddr == 0)
2422 fl4->saddr = inet_select_addr(dev_out, 0,
2423 RT_SCOPE_LINK);
2424 res->type = RTN_UNICAST;
2425 goto make_route;
2426 }
2427 rth = ERR_PTR(err);
2428 goto out;
2429 }
2430
2431 if (res->type == RTN_LOCAL) {
2432 if (!fl4->saddr) {
2433 if (res->fi->fib_prefsrc)
2434 fl4->saddr = res->fi->fib_prefsrc;
2435 else
2436 fl4->saddr = fl4->daddr;
2437 }
2438
2439
2440 dev_out = l3mdev_master_dev_rcu(FIB_RES_DEV(*res)) ? :
2441 net->loopback_dev;
2442 fl4->flowi4_oif = dev_out->ifindex;
2443 flags |= RTCF_LOCAL;
2444 goto make_route;
2445 }
2446
2447 fib_select_path(net, res, fl4, skb);
2448
2449 dev_out = FIB_RES_DEV(*res);
2450 fl4->flowi4_oif = dev_out->ifindex;
2451
2452
2453make_route:
2454 rth = __mkroute_output(res, fl4, orig_oif, dev_out, flags);
2455
2456out:
2457 return rth;
2458}
2459
2460static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2461{
2462 return NULL;
2463}
2464
2465static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
2466{
2467 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2468
2469 return mtu ? : dst->dev->mtu;
2470}
2471
2472static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
2473 struct sk_buff *skb, u32 mtu)
2474{
2475}
2476
2477static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
2478 struct sk_buff *skb)
2479{
2480}
2481
2482static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
2483 unsigned long old)
2484{
2485 return NULL;
2486}
2487
2488static struct dst_ops ipv4_dst_blackhole_ops = {
2489 .family = AF_INET,
2490 .check = ipv4_blackhole_dst_check,
2491 .mtu = ipv4_blackhole_mtu,
2492 .default_advmss = ipv4_default_advmss,
2493 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2494 .redirect = ipv4_rt_blackhole_redirect,
2495 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
2496 .neigh_lookup = ipv4_neigh_lookup,
2497};
2498
2499struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2500{
2501 struct rtable *ort = (struct rtable *) dst_orig;
2502 struct rtable *rt;
2503
2504 rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2505 if (rt) {
2506 struct dst_entry *new = &rt->dst;
2507
2508 new->__use = 1;
2509 new->input = dst_discard;
2510 new->output = dst_discard_out;
2511
2512 new->dev = net->loopback_dev;
2513 if (new->dev)
2514 dev_hold(new->dev);
2515
2516 rt->rt_is_input = ort->rt_is_input;
2517 rt->rt_iif = ort->rt_iif;
2518 rt->rt_pmtu = ort->rt_pmtu;
2519
2520 rt->rt_genid = rt_genid_ipv4(net);
2521 rt->rt_flags = ort->rt_flags;
2522 rt->rt_type = ort->rt_type;
2523 rt->rt_gateway = ort->rt_gateway;
2524 rt->rt_uses_gateway = ort->rt_uses_gateway;
2525
2526 INIT_LIST_HEAD(&rt->rt_uncached);
2527 }
2528
2529 dst_release(dst_orig);
2530
2531 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2532}
2533
2534struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
2535 const struct sock *sk)
2536{
2537 struct rtable *rt = __ip_route_output_key(net, flp4);
2538
2539 if (IS_ERR(rt))
2540 return rt;
2541
2542 if (flp4->flowi4_proto)
2543 rt = (struct rtable *)xfrm_lookup_route(net, &rt->dst,
2544 flowi4_to_flowi(flp4),
2545 sk, 0);
2546
2547 return rt;
2548}
2549EXPORT_SYMBOL_GPL(ip_route_output_flow);
2550
2551
2552static int rt_fill_info(struct net *net, __be32 dst, __be32 src, u32 table_id,
2553 struct flowi4 *fl4, struct sk_buff *skb, u32 portid,
2554 u32 seq)
2555{
2556 struct rtable *rt = skb_rtable(skb);
2557 struct rtmsg *r;
2558 struct nlmsghdr *nlh;
2559 unsigned long expires = 0;
2560 u32 error;
2561 u32 metrics[RTAX_MAX];
2562
2563 nlh = nlmsg_put(skb, portid, seq, RTM_NEWROUTE, sizeof(*r), 0);
2564 if (!nlh)
2565 return -EMSGSIZE;
2566
2567 r = nlmsg_data(nlh);
2568 r->rtm_family = AF_INET;
2569 r->rtm_dst_len = 32;
2570 r->rtm_src_len = 0;
2571 r->rtm_tos = fl4->flowi4_tos;
2572 r->rtm_table = table_id < 256 ? table_id : RT_TABLE_COMPAT;
2573 if (nla_put_u32(skb, RTA_TABLE, table_id))
2574 goto nla_put_failure;
2575 r->rtm_type = rt->rt_type;
2576 r->rtm_scope = RT_SCOPE_UNIVERSE;
2577 r->rtm_protocol = RTPROT_UNSPEC;
2578 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2579 if (rt->rt_flags & RTCF_NOTIFY)
2580 r->rtm_flags |= RTM_F_NOTIFY;
2581 if (IPCB(skb)->flags & IPSKB_DOREDIRECT)
2582 r->rtm_flags |= RTCF_DOREDIRECT;
2583
2584 if (nla_put_in_addr(skb, RTA_DST, dst))
2585 goto nla_put_failure;
2586 if (src) {
2587 r->rtm_src_len = 32;
2588 if (nla_put_in_addr(skb, RTA_SRC, src))
2589 goto nla_put_failure;
2590 }
2591 if (rt->dst.dev &&
2592 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2593 goto nla_put_failure;
2594#ifdef CONFIG_IP_ROUTE_CLASSID
2595 if (rt->dst.tclassid &&
2596 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2597 goto nla_put_failure;
2598#endif
2599 if (!rt_is_input_route(rt) &&
2600 fl4->saddr != src) {
2601 if (nla_put_in_addr(skb, RTA_PREFSRC, fl4->saddr))
2602 goto nla_put_failure;
2603 }
2604 if (rt->rt_uses_gateway &&
2605 nla_put_in_addr(skb, RTA_GATEWAY, rt->rt_gateway))
2606 goto nla_put_failure;
2607
2608 expires = rt->dst.expires;
2609 if (expires) {
2610 unsigned long now = jiffies;
2611
2612 if (time_before(now, expires))
2613 expires -= now;
2614 else
2615 expires = 0;
2616 }
2617
2618 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
2619 if (rt->rt_pmtu && expires)
2620 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2621 if (rtnetlink_put_metrics(skb, metrics) < 0)
2622 goto nla_put_failure;
2623
2624 if (fl4->flowi4_mark &&
2625 nla_put_u32(skb, RTA_MARK, fl4->flowi4_mark))
2626 goto nla_put_failure;
2627
2628 if (!uid_eq(fl4->flowi4_uid, INVALID_UID) &&
2629 nla_put_u32(skb, RTA_UID,
2630 from_kuid_munged(current_user_ns(), fl4->flowi4_uid)))
2631 goto nla_put_failure;
2632
2633 error = rt->dst.error;
2634
2635 if (rt_is_input_route(rt)) {
2636#ifdef CONFIG_IP_MROUTE
2637 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2638 IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
2639 int err = ipmr_get_route(net, skb,
2640 fl4->saddr, fl4->daddr,
2641 r, portid);
2642
2643 if (err <= 0) {
2644 if (err == 0)
2645 return 0;
2646 goto nla_put_failure;
2647 }
2648 } else
2649#endif
2650 if (nla_put_u32(skb, RTA_IIF, skb->dev->ifindex))
2651 goto nla_put_failure;
2652 }
2653
2654 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
2655 goto nla_put_failure;
2656
2657 nlmsg_end(skb, nlh);
2658 return 0;
2659
2660nla_put_failure:
2661 nlmsg_cancel(skb, nlh);
2662 return -EMSGSIZE;
2663}
2664
2665static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
2666 struct netlink_ext_ack *extack)
2667{
2668 struct net *net = sock_net(in_skb->sk);
2669 struct rtmsg *rtm;
2670 struct nlattr *tb[RTA_MAX+1];
2671 struct fib_result res = {};
2672 struct rtable *rt = NULL;
2673 struct flowi4 fl4;
2674 __be32 dst = 0;
2675 __be32 src = 0;
2676 u32 iif;
2677 int err;
2678 int mark;
2679 struct sk_buff *skb;
2680 u32 table_id = RT_TABLE_MAIN;
2681 kuid_t uid;
2682
2683 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy,
2684 extack);
2685 if (err < 0)
2686 goto errout;
2687
2688 rtm = nlmsg_data(nlh);
2689
2690 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2691 if (!skb) {
2692 err = -ENOBUFS;
2693 goto errout;
2694 }
2695
2696
2697
2698
2699 skb_reset_mac_header(skb);
2700 skb_reset_network_header(skb);
2701
2702 src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0;
2703 dst = tb[RTA_DST] ? nla_get_in_addr(tb[RTA_DST]) : 0;
2704 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2705 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2706 if (tb[RTA_UID])
2707 uid = make_kuid(current_user_ns(), nla_get_u32(tb[RTA_UID]));
2708 else
2709 uid = (iif ? INVALID_UID : current_uid());
2710
2711
2712
2713
2714 ip_hdr(skb)->protocol = IPPROTO_UDP;
2715 ip_hdr(skb)->saddr = src;
2716 ip_hdr(skb)->daddr = dst;
2717
2718 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2719
2720 memset(&fl4, 0, sizeof(fl4));
2721 fl4.daddr = dst;
2722 fl4.saddr = src;
2723 fl4.flowi4_tos = rtm->rtm_tos;
2724 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2725 fl4.flowi4_mark = mark;
2726 fl4.flowi4_uid = uid;
2727
2728 rcu_read_lock();
2729
2730 if (iif) {
2731 struct net_device *dev;
2732
2733 dev = dev_get_by_index_rcu(net, iif);
2734 if (!dev) {
2735 err = -ENODEV;
2736 goto errout_free;
2737 }
2738
2739 skb->protocol = htons(ETH_P_IP);
2740 skb->dev = dev;
2741 skb->mark = mark;
2742 err = ip_route_input_rcu(skb, dst, src, rtm->rtm_tos,
2743 dev, &res);
2744
2745 rt = skb_rtable(skb);
2746 if (err == 0 && rt->dst.error)
2747 err = -rt->dst.error;
2748 } else {
2749 rt = ip_route_output_key_hash_rcu(net, &fl4, &res, skb);
2750 err = 0;
2751 if (IS_ERR(rt))
2752 err = PTR_ERR(rt);
2753 else
2754 skb_dst_set(skb, &rt->dst);
2755 }
2756
2757 if (err)
2758 goto errout_free;
2759
2760 if (rtm->rtm_flags & RTM_F_NOTIFY)
2761 rt->rt_flags |= RTCF_NOTIFY;
2762
2763 if (rtm->rtm_flags & RTM_F_LOOKUP_TABLE)
2764 table_id = rt->rt_table_id;
2765
2766 if (rtm->rtm_flags & RTM_F_FIB_MATCH) {
2767 if (!res.fi) {
2768 err = fib_props[res.type].error;
2769 if (!err)
2770 err = -EHOSTUNREACH;
2771 goto errout_free;
2772 }
2773 err = fib_dump_info(skb, NETLINK_CB(in_skb).portid,
2774 nlh->nlmsg_seq, RTM_NEWROUTE, table_id,
2775 rt->rt_type, res.prefix, res.prefixlen,
2776 fl4.flowi4_tos, res.fi, 0);
2777 } else {
2778 err = rt_fill_info(net, dst, src, table_id, &fl4, skb,
2779 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq);
2780 }
2781 if (err < 0)
2782 goto errout_free;
2783
2784 rcu_read_unlock();
2785
2786 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2787errout:
2788 return err;
2789
2790errout_free:
2791 rcu_read_unlock();
2792 kfree_skb(skb);
2793 goto errout;
2794}
2795
2796void ip_rt_multicast_event(struct in_device *in_dev)
2797{
2798 rt_cache_flush(dev_net(in_dev->dev));
2799}
2800
2801#ifdef CONFIG_SYSCTL
2802static int ip_rt_gc_interval __read_mostly = 60 * HZ;
2803static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
2804static int ip_rt_gc_elasticity __read_mostly = 8;
2805
2806static int ipv4_sysctl_rtcache_flush(struct ctl_table *__ctl, int write,
2807 void __user *buffer,
2808 size_t *lenp, loff_t *ppos)
2809{
2810 struct net *net = (struct net *)__ctl->extra1;
2811
2812 if (write) {
2813 rt_cache_flush(net);
2814 fnhe_genid_bump(net);
2815 return 0;
2816 }
2817
2818 return -EINVAL;
2819}
2820
2821static struct ctl_table ipv4_route_table[] = {
2822 {
2823 .procname = "gc_thresh",
2824 .data = &ipv4_dst_ops.gc_thresh,
2825 .maxlen = sizeof(int),
2826 .mode = 0644,
2827 .proc_handler = proc_dointvec,
2828 },
2829 {
2830 .procname = "max_size",
2831 .data = &ip_rt_max_size,
2832 .maxlen = sizeof(int),
2833 .mode = 0644,
2834 .proc_handler = proc_dointvec,
2835 },
2836 {
2837
2838
2839 .procname = "gc_min_interval",
2840 .data = &ip_rt_gc_min_interval,
2841 .maxlen = sizeof(int),
2842 .mode = 0644,
2843 .proc_handler = proc_dointvec_jiffies,
2844 },
2845 {
2846 .procname = "gc_min_interval_ms",
2847 .data = &ip_rt_gc_min_interval,
2848 .maxlen = sizeof(int),
2849 .mode = 0644,
2850 .proc_handler = proc_dointvec_ms_jiffies,
2851 },
2852 {
2853 .procname = "gc_timeout",
2854 .data = &ip_rt_gc_timeout,
2855 .maxlen = sizeof(int),
2856 .mode = 0644,
2857 .proc_handler = proc_dointvec_jiffies,
2858 },
2859 {
2860 .procname = "gc_interval",
2861 .data = &ip_rt_gc_interval,
2862 .maxlen = sizeof(int),
2863 .mode = 0644,
2864 .proc_handler = proc_dointvec_jiffies,
2865 },
2866 {
2867 .procname = "redirect_load",
2868 .data = &ip_rt_redirect_load,
2869 .maxlen = sizeof(int),
2870 .mode = 0644,
2871 .proc_handler = proc_dointvec,
2872 },
2873 {
2874 .procname = "redirect_number",
2875 .data = &ip_rt_redirect_number,
2876 .maxlen = sizeof(int),
2877 .mode = 0644,
2878 .proc_handler = proc_dointvec,
2879 },
2880 {
2881 .procname = "redirect_silence",
2882 .data = &ip_rt_redirect_silence,
2883 .maxlen = sizeof(int),
2884 .mode = 0644,
2885 .proc_handler = proc_dointvec,
2886 },
2887 {
2888 .procname = "error_cost",
2889 .data = &ip_rt_error_cost,
2890 .maxlen = sizeof(int),
2891 .mode = 0644,
2892 .proc_handler = proc_dointvec,
2893 },
2894 {
2895 .procname = "error_burst",
2896 .data = &ip_rt_error_burst,
2897 .maxlen = sizeof(int),
2898 .mode = 0644,
2899 .proc_handler = proc_dointvec,
2900 },
2901 {
2902 .procname = "gc_elasticity",
2903 .data = &ip_rt_gc_elasticity,
2904 .maxlen = sizeof(int),
2905 .mode = 0644,
2906 .proc_handler = proc_dointvec,
2907 },
2908 {
2909 .procname = "mtu_expires",
2910 .data = &ip_rt_mtu_expires,
2911 .maxlen = sizeof(int),
2912 .mode = 0644,
2913 .proc_handler = proc_dointvec_jiffies,
2914 },
2915 {
2916 .procname = "min_pmtu",
2917 .data = &ip_rt_min_pmtu,
2918 .maxlen = sizeof(int),
2919 .mode = 0644,
2920 .proc_handler = proc_dointvec,
2921 },
2922 {
2923 .procname = "min_adv_mss",
2924 .data = &ip_rt_min_advmss,
2925 .maxlen = sizeof(int),
2926 .mode = 0644,
2927 .proc_handler = proc_dointvec,
2928 },
2929 { }
2930};
2931
2932static struct ctl_table ipv4_route_flush_table[] = {
2933 {
2934 .procname = "flush",
2935 .maxlen = sizeof(int),
2936 .mode = 0200,
2937 .proc_handler = ipv4_sysctl_rtcache_flush,
2938 },
2939 { },
2940};
2941
2942static __net_init int sysctl_route_net_init(struct net *net)
2943{
2944 struct ctl_table *tbl;
2945
2946 tbl = ipv4_route_flush_table;
2947 if (!net_eq(net, &init_net)) {
2948 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
2949 if (!tbl)
2950 goto err_dup;
2951
2952
2953 if (net->user_ns != &init_user_ns)
2954 tbl[0].procname = NULL;
2955 }
2956 tbl[0].extra1 = net;
2957
2958 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
2959 if (!net->ipv4.route_hdr)
2960 goto err_reg;
2961 return 0;
2962
2963err_reg:
2964 if (tbl != ipv4_route_flush_table)
2965 kfree(tbl);
2966err_dup:
2967 return -ENOMEM;
2968}
2969
2970static __net_exit void sysctl_route_net_exit(struct net *net)
2971{
2972 struct ctl_table *tbl;
2973
2974 tbl = net->ipv4.route_hdr->ctl_table_arg;
2975 unregister_net_sysctl_table(net->ipv4.route_hdr);
2976 BUG_ON(tbl == ipv4_route_flush_table);
2977 kfree(tbl);
2978}
2979
2980static __net_initdata struct pernet_operations sysctl_route_ops = {
2981 .init = sysctl_route_net_init,
2982 .exit = sysctl_route_net_exit,
2983};
2984#endif
2985
2986static __net_init int rt_genid_init(struct net *net)
2987{
2988 atomic_set(&net->ipv4.rt_genid, 0);
2989 atomic_set(&net->fnhe_genid, 0);
2990 atomic_set(&net->ipv4.dev_addr_genid, get_random_int());
2991 return 0;
2992}
2993
2994static __net_initdata struct pernet_operations rt_genid_ops = {
2995 .init = rt_genid_init,
2996};
2997
2998static int __net_init ipv4_inetpeer_init(struct net *net)
2999{
3000 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3001
3002 if (!bp)
3003 return -ENOMEM;
3004 inet_peer_base_init(bp);
3005 net->ipv4.peers = bp;
3006 return 0;
3007}
3008
3009static void __net_exit ipv4_inetpeer_exit(struct net *net)
3010{
3011 struct inet_peer_base *bp = net->ipv4.peers;
3012
3013 net->ipv4.peers = NULL;
3014 inetpeer_invalidate_tree(bp);
3015 kfree(bp);
3016}
3017
3018static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
3019 .init = ipv4_inetpeer_init,
3020 .exit = ipv4_inetpeer_exit,
3021};
3022
3023#ifdef CONFIG_IP_ROUTE_CLASSID
3024struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
3025#endif
3026
3027int __init ip_rt_init(void)
3028{
3029 int rc = 0;
3030 int cpu;
3031
3032 ip_idents = kmalloc(IP_IDENTS_SZ * sizeof(*ip_idents), GFP_KERNEL);
3033 if (!ip_idents)
3034 panic("IP: failed to allocate ip_idents\n");
3035
3036 prandom_bytes(ip_idents, IP_IDENTS_SZ * sizeof(*ip_idents));
3037
3038 ip_tstamps = kcalloc(IP_IDENTS_SZ, sizeof(*ip_tstamps), GFP_KERNEL);
3039 if (!ip_tstamps)
3040 panic("IP: failed to allocate ip_tstamps\n");
3041
3042 for_each_possible_cpu(cpu) {
3043 struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
3044
3045 INIT_LIST_HEAD(&ul->head);
3046 spin_lock_init(&ul->lock);
3047 }
3048#ifdef CONFIG_IP_ROUTE_CLASSID
3049 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
3050 if (!ip_rt_acct)
3051 panic("IP: failed to allocate ip_rt_acct\n");
3052#endif
3053
3054 ipv4_dst_ops.kmem_cachep =
3055 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
3056 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
3057
3058 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
3059
3060 if (dst_entries_init(&ipv4_dst_ops) < 0)
3061 panic("IP: failed to allocate ipv4_dst_ops counter\n");
3062
3063 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
3064 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
3065
3066 ipv4_dst_ops.gc_thresh = ~0;
3067 ip_rt_max_size = INT_MAX;
3068
3069 devinet_init();
3070 ip_fib_init();
3071
3072 if (ip_rt_proc_init())
3073 pr_err("Unable to create route proc files\n");
3074#ifdef CONFIG_XFRM
3075 xfrm_init();
3076 xfrm4_init();
3077#endif
3078 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL);
3079
3080#ifdef CONFIG_SYSCTL
3081 register_pernet_subsys(&sysctl_route_ops);
3082#endif
3083 register_pernet_subsys(&rt_genid_ops);
3084 register_pernet_subsys(&ipv4_inetpeer_ops);
3085 return rc;
3086}
3087
3088#ifdef CONFIG_SYSCTL
3089
3090
3091
3092
3093void __init ip_static_sysctl_init(void)
3094{
3095 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);
3096}
3097#endif
3098