?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
[ARM] 5113/1: PXA SSP: Additional register definitions for PXA3xx SSP
[zen-stable.git] / net / ipv6 / route.c
blob12bba0880345474e13a02bf42f6ab44cdbeb19e7
1 /*
2 * Linux INET6 implementation
3 * FIB front-end.
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 *
8 * $Id: route.c,v 1.56 2001/10/31 21:55:55 davem Exp $
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
15
16 /* Changes:
17 *
18 * YOSHIFUJI Hideaki @USAGI
19 * reworked default router selection.
20 * - respect outgoing interface
21 * - select from (probably) reachable routers (i.e.
22 * routers in REACHABLE, STALE, DELAY or PROBE states).
23 * - always select the same router if it is (probably)
24 * reachable. otherwise, round-robin the list.
25 * Ville Nuorvala
26 * Fixed routing subtrees.
27 */
28
29 #include <linux/capability.h>
30 #include <linux/errno.h>
31 #include <linux/types.h>
32 #include <linux/times.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/net.h>
36 #include <linux/route.h>
37 #include <linux/netdevice.h>
38 #include <linux/in6.h>
39 #include <linux/mroute6.h>
40 #include <linux/init.h>
41 #include <linux/if_arp.h>
42 #include <linux/proc_fs.h>
43 #include <linux/seq_file.h>
44 #include <linux/nsproxy.h>
45 #include <net/net_namespace.h>
46 #include <net/snmp.h>
47 #include <net/ipv6.h>
48 #include <net/ip6_fib.h>
49 #include <net/ip6_route.h>
50 #include <net/ndisc.h>
51 #include <net/addrconf.h>
52 #include <net/tcp.h>
53 #include <linux/rtnetlink.h>
54 #include <net/dst.h>
55 #include <net/xfrm.h>
56 #include <net/netevent.h>
57 #include <net/netlink.h>
58
59 #include <asm/uaccess.h>
60
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64
65 /* Set to 3 to get tracing. */
66 #define RT6_DEBUG 2
67
68 #if RT6_DEBUG >= 3
69 #define RDBG(x) printk x
70 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
71 #else
72 #define RDBG(x)
73 #define RT6_TRACE(x...) do { ; } while (0)
74 #endif
75
76 #define CLONE_OFFLINK_ROUTE 0
77
78 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
79 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
80 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
81 static void ip6_dst_destroy(struct dst_entry *);
82 static void ip6_dst_ifdown(struct dst_entry *,
83 struct net_device *dev, int how);
84 static int ip6_dst_gc(struct dst_ops *ops);
85
86 static int ip6_pkt_discard(struct sk_buff *skb);
87 static int ip6_pkt_discard_out(struct sk_buff *skb);
88 static void ip6_link_failure(struct sk_buff *skb);
89 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
90
91 #ifdef CONFIG_IPV6_ROUTE_INFO
92 static struct rt6_info *rt6_add_route_info(struct net *net,
93 struct in6_addr *prefix, int prefixlen,
94 struct in6_addr *gwaddr, int ifindex,
95 unsigned pref);
96 static struct rt6_info *rt6_get_route_info(struct net *net,
97 struct in6_addr *prefix, int prefixlen,
98 struct in6_addr *gwaddr, int ifindex);
99 #endif
100
101 static struct dst_ops ip6_dst_ops_template = {
102 .family = AF_INET6,
103 .protocol = __constant_htons(ETH_P_IPV6),
104 .gc = ip6_dst_gc,
105 .gc_thresh = 1024,
106 .check = ip6_dst_check,
107 .destroy = ip6_dst_destroy,
108 .ifdown = ip6_dst_ifdown,
109 .negative_advice = ip6_negative_advice,
110 .link_failure = ip6_link_failure,
111 .update_pmtu = ip6_rt_update_pmtu,
112 .local_out = ip6_local_out,
113 .entry_size = sizeof(struct rt6_info),
114 .entries = ATOMIC_INIT(0),
115 };
116
117 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
118 {
119 }
120
121 static struct dst_ops ip6_dst_blackhole_ops = {
122 .family = AF_INET6,
123 .protocol = __constant_htons(ETH_P_IPV6),
124 .destroy = ip6_dst_destroy,
125 .check = ip6_dst_check,
126 .update_pmtu = ip6_rt_blackhole_update_pmtu,
127 .entry_size = sizeof(struct rt6_info),
128 .entries = ATOMIC_INIT(0),
129 };
130
131 static struct rt6_info ip6_null_entry_template = {
132 .u = {
133 .dst = {
134 .__refcnt = ATOMIC_INIT(1),
135 .__use = 1,
136 .obsolete = -1,
137 .error = -ENETUNREACH,
138 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
139 .input = ip6_pkt_discard,
140 .output = ip6_pkt_discard_out,
141 }
142 },
143 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
144 .rt6i_metric = ~(u32) 0,
145 .rt6i_ref = ATOMIC_INIT(1),
146 };
147
148 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
149
150 static int ip6_pkt_prohibit(struct sk_buff *skb);
151 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
152
153 static struct rt6_info ip6_prohibit_entry_template = {
154 .u = {
155 .dst = {
156 .__refcnt = ATOMIC_INIT(1),
157 .__use = 1,
158 .obsolete = -1,
159 .error = -EACCES,
160 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
161 .input = ip6_pkt_prohibit,
162 .output = ip6_pkt_prohibit_out,
163 }
164 },
165 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
166 .rt6i_metric = ~(u32) 0,
167 .rt6i_ref = ATOMIC_INIT(1),
168 };
169
170 static struct rt6_info ip6_blk_hole_entry_template = {
171 .u = {
172 .dst = {
173 .__refcnt = ATOMIC_INIT(1),
174 .__use = 1,
175 .obsolete = -1,
176 .error = -EINVAL,
177 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
178 .input = dst_discard,
179 .output = dst_discard,
180 }
181 },
182 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
183 .rt6i_metric = ~(u32) 0,
184 .rt6i_ref = ATOMIC_INIT(1),
185 };
186
187 #endif
188
189 /* allocate dst with ip6_dst_ops */
190 static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops)
191 {
192 return (struct rt6_info *)dst_alloc(ops);
193 }
194
195 static void ip6_dst_destroy(struct dst_entry *dst)
196 {
197 struct rt6_info *rt = (struct rt6_info *)dst;
198 struct inet6_dev *idev = rt->rt6i_idev;
199
200 if (idev != NULL) {
201 rt->rt6i_idev = NULL;
202 in6_dev_put(idev);
203 }
204 }
205
206 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
207 int how)
208 {
209 struct rt6_info *rt = (struct rt6_info *)dst;
210 struct inet6_dev *idev = rt->rt6i_idev;
211 struct net_device *loopback_dev =
212 dev_net(dev)->loopback_dev;
213
214 if (dev != loopback_dev && idev != NULL && idev->dev == dev) {
215 struct inet6_dev *loopback_idev =
216 in6_dev_get(loopback_dev);
217 if (loopback_idev != NULL) {
218 rt->rt6i_idev = loopback_idev;
219 in6_dev_put(idev);
220 }
221 }
222 }
223
224 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
225 {
226 return (rt->rt6i_flags & RTF_EXPIRES &&
227 time_after(jiffies, rt->rt6i_expires));
228 }
229
230 static inline int rt6_need_strict(struct in6_addr *daddr)
231 {
232 return (ipv6_addr_type(daddr) &
233 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
234 }
235
236 /*
237 * Route lookup. Any table->tb6_lock is implied.
238 */
239
240 static inline struct rt6_info *rt6_device_match(struct net *net,
241 struct rt6_info *rt,
242 int oif,
243 int strict)
244 {
245 struct rt6_info *local = NULL;
246 struct rt6_info *sprt;
247
248 if (oif) {
249 for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) {
250 struct net_device *dev = sprt->rt6i_dev;
251 if (dev->ifindex == oif)
252 return sprt;
253 if (dev->flags & IFF_LOOPBACK) {
254 if (sprt->rt6i_idev == NULL ||
255 sprt->rt6i_idev->dev->ifindex != oif) {
256 if (strict && oif)
257 continue;
258 if (local && (!oif ||
259 local->rt6i_idev->dev->ifindex == oif))
260 continue;
261 }
262 local = sprt;
263 }
264 }
265
266 if (local)
267 return local;
268
269 if (strict)
270 return net->ipv6.ip6_null_entry;
271 }
272 return rt;
273 }
274
275 #ifdef CONFIG_IPV6_ROUTER_PREF
276 static void rt6_probe(struct rt6_info *rt)
277 {
278 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
279 /*
280 * Okay, this does not seem to be appropriate
281 * for now, however, we need to check if it
282 * is really so; aka Router Reachability Probing.
283 *
284 * Router Reachability Probe MUST be rate-limited
285 * to no more than one per minute.
286 */
287 if (!neigh || (neigh->nud_state & NUD_VALID))
288 return;
289 read_lock_bh(&neigh->lock);
290 if (!(neigh->nud_state & NUD_VALID) &&
291 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
292 struct in6_addr mcaddr;
293 struct in6_addr *target;
294
295 neigh->updated = jiffies;
296 read_unlock_bh(&neigh->lock);
297
298 target = (struct in6_addr *)&neigh->primary_key;
299 addrconf_addr_solict_mult(target, &mcaddr);
300 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
301 } else
302 read_unlock_bh(&neigh->lock);
303 }
304 #else
305 static inline void rt6_probe(struct rt6_info *rt)
306 {
307 return;
308 }
309 #endif
310
311 /*
312 * Default Router Selection (RFC 2461 6.3.6)
313 */
314 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
315 {
316 struct net_device *dev = rt->rt6i_dev;
317 if (!oif || dev->ifindex == oif)
318 return 2;
319 if ((dev->flags & IFF_LOOPBACK) &&
320 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
321 return 1;
322 return 0;
323 }
324
325 static inline int rt6_check_neigh(struct rt6_info *rt)
326 {
327 struct neighbour *neigh = rt->rt6i_nexthop;
328 int m;
329 if (rt->rt6i_flags & RTF_NONEXTHOP ||
330 !(rt->rt6i_flags & RTF_GATEWAY))
331 m = 1;
332 else if (neigh) {
333 read_lock_bh(&neigh->lock);
334 if (neigh->nud_state & NUD_VALID)
335 m = 2;
336 #ifdef CONFIG_IPV6_ROUTER_PREF
337 else if (neigh->nud_state & NUD_FAILED)
338 m = 0;
339 #endif
340 else
341 m = 1;
342 read_unlock_bh(&neigh->lock);
343 } else
344 m = 0;
345 return m;
346 }
347
348 static int rt6_score_route(struct rt6_info *rt, int oif,
349 int strict)
350 {
351 int m, n;
352
353 m = rt6_check_dev(rt, oif);
354 if (!m && (strict & RT6_LOOKUP_F_IFACE))
355 return -1;
356 #ifdef CONFIG_IPV6_ROUTER_PREF
357 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
358 #endif
359 n = rt6_check_neigh(rt);
360 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
361 return -1;
362 return m;
363 }
364
365 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
366 int *mpri, struct rt6_info *match)
367 {
368 int m;
369
370 if (rt6_check_expired(rt))
371 goto out;
372
373 m = rt6_score_route(rt, oif, strict);
374 if (m < 0)
375 goto out;
376
377 if (m > *mpri) {
378 if (strict & RT6_LOOKUP_F_REACHABLE)
379 rt6_probe(match);
380 *mpri = m;
381 match = rt;
382 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
383 rt6_probe(rt);
384 }
385
386 out:
387 return match;
388 }
389
390 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
391 struct rt6_info *rr_head,
392 u32 metric, int oif, int strict)
393 {
394 struct rt6_info *rt, *match;
395 int mpri = -1;
396
397 match = NULL;
398 for (rt = rr_head; rt && rt->rt6i_metric == metric;
399 rt = rt->u.dst.rt6_next)
400 match = find_match(rt, oif, strict, &mpri, match);
401 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
402 rt = rt->u.dst.rt6_next)
403 match = find_match(rt, oif, strict, &mpri, match);
404
405 return match;
406 }
407
408 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
409 {
410 struct rt6_info *match, *rt0;
411 struct net *net;
412
413 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
414 __func__, fn->leaf, oif);
415
416 rt0 = fn->rr_ptr;
417 if (!rt0)
418 fn->rr_ptr = rt0 = fn->leaf;
419
420 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
421
422 if (!match &&
423 (strict & RT6_LOOKUP_F_REACHABLE)) {
424 struct rt6_info *next = rt0->u.dst.rt6_next;
425
426 /* no entries matched; do round-robin */
427 if (!next || next->rt6i_metric != rt0->rt6i_metric)
428 next = fn->leaf;
429
430 if (next != rt0)
431 fn->rr_ptr = next;
432 }
433
434 RT6_TRACE("%s() => %p\n",
435 __func__, match);
436
437 net = dev_net(rt0->rt6i_dev);
438 return (match ? match : net->ipv6.ip6_null_entry);
439 }
440
441 #ifdef CONFIG_IPV6_ROUTE_INFO
442 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
443 struct in6_addr *gwaddr)
444 {
445 struct net *net = dev_net(dev);
446 struct route_info *rinfo = (struct route_info *) opt;
447 struct in6_addr prefix_buf, *prefix;
448 unsigned int pref;
449 u32 lifetime;
450 struct rt6_info *rt;
451
452 if (len < sizeof(struct route_info)) {
453 return -EINVAL;
454 }
455
456 /* Sanity check for prefix_len and length */
457 if (rinfo->length > 3) {
458 return -EINVAL;
459 } else if (rinfo->prefix_len > 128) {
460 return -EINVAL;
461 } else if (rinfo->prefix_len > 64) {
462 if (rinfo->length < 2) {
463 return -EINVAL;
464 }
465 } else if (rinfo->prefix_len > 0) {
466 if (rinfo->length < 1) {
467 return -EINVAL;
468 }
469 }
470
471 pref = rinfo->route_pref;
472 if (pref == ICMPV6_ROUTER_PREF_INVALID)
473 pref = ICMPV6_ROUTER_PREF_MEDIUM;
474
475 lifetime = ntohl(rinfo->lifetime);
476 if (lifetime == 0xffffffff) {
477 /* infinity */
478 } else if (lifetime > 0x7fffffff/HZ) {
479 /* Avoid arithmetic overflow */
480 lifetime = 0x7fffffff/HZ - 1;
481 }
482
483 if (rinfo->length == 3)
484 prefix = (struct in6_addr *)rinfo->prefix;
485 else {
486 /* this function is safe */
487 ipv6_addr_prefix(&prefix_buf,
488 (struct in6_addr *)rinfo->prefix,
489 rinfo->prefix_len);
490 prefix = &prefix_buf;
491 }
492
493 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
494 dev->ifindex);
495
496 if (rt && !lifetime) {
497 ip6_del_rt(rt);
498 rt = NULL;
499 }
500
501 if (!rt && lifetime)
502 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
503 pref);
504 else if (rt)
505 rt->rt6i_flags = RTF_ROUTEINFO |
506 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
507
508 if (rt) {
509 if (lifetime == 0xffffffff) {
510 rt->rt6i_flags &= ~RTF_EXPIRES;
511 } else {
512 rt->rt6i_expires = jiffies + HZ * lifetime;
513 rt->rt6i_flags |= RTF_EXPIRES;
514 }
515 dst_release(&rt->u.dst);
516 }
517 return 0;
518 }
519 #endif
520
521 #define BACKTRACK(__net, saddr) \
522 do { \
523 if (rt == __net->ipv6.ip6_null_entry) { \
524 struct fib6_node *pn; \
525 while (1) { \
526 if (fn->fn_flags & RTN_TL_ROOT) \
527 goto out; \
528 pn = fn->parent; \
529 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
530 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
531 else \
532 fn = pn; \
533 if (fn->fn_flags & RTN_RTINFO) \
534 goto restart; \
535 } \
536 } \
537 } while(0)
538
539 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
540 struct fib6_table *table,
541 struct flowi *fl, int flags)
542 {
543 struct fib6_node *fn;
544 struct rt6_info *rt;
545
546 read_lock_bh(&table->tb6_lock);
547 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
548 restart:
549 rt = fn->leaf;
550 rt = rt6_device_match(net, rt, fl->oif, flags);
551 BACKTRACK(net, &fl->fl6_src);
552 out:
553 dst_use(&rt->u.dst, jiffies);
554 read_unlock_bh(&table->tb6_lock);
555 return rt;
556
557 }
558
559 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
560 const struct in6_addr *saddr, int oif, int strict)
561 {
562 struct flowi fl = {
563 .oif = oif,
564 .nl_u = {
565 .ip6_u = {
566 .daddr = *daddr,
567 },
568 },
569 };
570 struct dst_entry *dst;
571 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
572
573 if (saddr) {
574 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
575 flags |= RT6_LOOKUP_F_HAS_SADDR;
576 }
577
578 dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_lookup);
579 if (dst->error == 0)
580 return (struct rt6_info *) dst;
581
582 dst_release(dst);
583
584 return NULL;
585 }
586
587 EXPORT_SYMBOL(rt6_lookup);
588
589 /* ip6_ins_rt is called with FREE table->tb6_lock.
590 It takes new route entry, the addition fails by any reason the
591 route is freed. In any case, if caller does not hold it, it may
592 be destroyed.
593 */
594
595 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
596 {
597 int err;
598 struct fib6_table *table;
599
600 table = rt->rt6i_table;
601 write_lock_bh(&table->tb6_lock);
602 err = fib6_add(&table->tb6_root, rt, info);
603 write_unlock_bh(&table->tb6_lock);
604
605 return err;
606 }
607
608 int ip6_ins_rt(struct rt6_info *rt)
609 {
610 struct nl_info info = {
611 .nl_net = dev_net(rt->rt6i_dev),
612 };
613 return __ip6_ins_rt(rt, &info);
614 }
615
616 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
617 struct in6_addr *saddr)
618 {
619 struct rt6_info *rt;
620
621 /*
622 * Clone the route.
623 */
624
625 rt = ip6_rt_copy(ort);
626
627 if (rt) {
628 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
629 if (rt->rt6i_dst.plen != 128 &&
630 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
631 rt->rt6i_flags |= RTF_ANYCAST;
632 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
633 }
634
635 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
636 rt->rt6i_dst.plen = 128;
637 rt->rt6i_flags |= RTF_CACHE;
638 rt->u.dst.flags |= DST_HOST;
639
640 #ifdef CONFIG_IPV6_SUBTREES
641 if (rt->rt6i_src.plen && saddr) {
642 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
643 rt->rt6i_src.plen = 128;
644 }
645 #endif
646
647 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
648
649 }
650
651 return rt;
652 }
653
654 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
655 {
656 struct rt6_info *rt = ip6_rt_copy(ort);
657 if (rt) {
658 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
659 rt->rt6i_dst.plen = 128;
660 rt->rt6i_flags |= RTF_CACHE;
661 rt->u.dst.flags |= DST_HOST;
662 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
663 }
664 return rt;
665 }
666
667 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
668 struct flowi *fl, int flags)
669 {
670 struct fib6_node *fn;
671 struct rt6_info *rt, *nrt;
672 int strict = 0;
673 int attempts = 3;
674 int err;
675 int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
676
677 strict |= flags & RT6_LOOKUP_F_IFACE;
678
679 relookup:
680 read_lock_bh(&table->tb6_lock);
681
682 restart_2:
683 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
684
685 restart:
686 rt = rt6_select(fn, oif, strict | reachable);
687
688 BACKTRACK(net, &fl->fl6_src);
689 if (rt == net->ipv6.ip6_null_entry ||
690 rt->rt6i_flags & RTF_CACHE)
691 goto out;
692
693 dst_hold(&rt->u.dst);
694 read_unlock_bh(&table->tb6_lock);
695
696 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
697 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
698 else {
699 #if CLONE_OFFLINK_ROUTE
700 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
701 #else
702 goto out2;
703 #endif
704 }
705
706 dst_release(&rt->u.dst);
707 rt = nrt ? : net->ipv6.ip6_null_entry;
708
709 dst_hold(&rt->u.dst);
710 if (nrt) {
711 err = ip6_ins_rt(nrt);
712 if (!err)
713 goto out2;
714 }
715
716 if (--attempts <= 0)
717 goto out2;
718
719 /*
720 * Race condition! In the gap, when table->tb6_lock was
721 * released someone could insert this route. Relookup.
722 */
723 dst_release(&rt->u.dst);
724 goto relookup;
725
726 out:
727 if (reachable) {
728 reachable = 0;
729 goto restart_2;
730 }
731 dst_hold(&rt->u.dst);
732 read_unlock_bh(&table->tb6_lock);
733 out2:
734 rt->u.dst.lastuse = jiffies;
735 rt->u.dst.__use++;
736
737 return rt;
738 }
739
740 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
741 struct flowi *fl, int flags)
742 {
743 return ip6_pol_route(net, table, fl->iif, fl, flags);
744 }
745
746 void ip6_route_input(struct sk_buff *skb)
747 {
748 struct ipv6hdr *iph = ipv6_hdr(skb);
749 struct net *net = dev_net(skb->dev);
750 int flags = RT6_LOOKUP_F_HAS_SADDR;
751 struct flowi fl = {
752 .iif = skb->dev->ifindex,
753 .nl_u = {
754 .ip6_u = {
755 .daddr = iph->daddr,
756 .saddr = iph->saddr,
757 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
758 },
759 },
760 .mark = skb->mark,
761 .proto = iph->nexthdr,
762 };
763
764 if (rt6_need_strict(&iph->daddr))
765 flags |= RT6_LOOKUP_F_IFACE;
766
767 skb->dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_input);
768 }
769
770 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
771 struct flowi *fl, int flags)
772 {
773 return ip6_pol_route(net, table, fl->oif, fl, flags);
774 }
775
776 struct dst_entry * ip6_route_output(struct net *net, struct sock *sk,
777 struct flowi *fl)
778 {
779 int flags = 0;
780
781 if (rt6_need_strict(&fl->fl6_dst))
782 flags |= RT6_LOOKUP_F_IFACE;
783
784 if (!ipv6_addr_any(&fl->fl6_src))
785 flags |= RT6_LOOKUP_F_HAS_SADDR;
786 else if (sk) {
787 unsigned int prefs = inet6_sk(sk)->srcprefs;
788 if (prefs & IPV6_PREFER_SRC_TMP)
789 flags |= RT6_LOOKUP_F_SRCPREF_TMP;
790 if (prefs & IPV6_PREFER_SRC_PUBLIC)
791 flags |= RT6_LOOKUP_F_SRCPREF_PUBLIC;
792 if (prefs & IPV6_PREFER_SRC_COA)
793 flags |= RT6_LOOKUP_F_SRCPREF_COA;
794 }
795
796 return fib6_rule_lookup(net, fl, flags, ip6_pol_route_output);
797 }
798
799 EXPORT_SYMBOL(ip6_route_output);
800
801 int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl)
802 {
803 struct rt6_info *ort = (struct rt6_info *) *dstp;
804 struct rt6_info *rt = (struct rt6_info *)
805 dst_alloc(&ip6_dst_blackhole_ops);
806 struct dst_entry *new = NULL;
807
808 if (rt) {
809 new = &rt->u.dst;
810
811 atomic_set(&new->__refcnt, 1);
812 new->__use = 1;
813 new->input = dst_discard;
814 new->output = dst_discard;
815
816 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
817 new->dev = ort->u.dst.dev;
818 if (new->dev)
819 dev_hold(new->dev);
820 rt->rt6i_idev = ort->rt6i_idev;
821 if (rt->rt6i_idev)
822 in6_dev_hold(rt->rt6i_idev);
823 rt->rt6i_expires = 0;
824
825 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
826 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
827 rt->rt6i_metric = 0;
828
829 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
830 #ifdef CONFIG_IPV6_SUBTREES
831 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
832 #endif
833
834 dst_free(new);
835 }
836
837 dst_release(*dstp);
838 *dstp = new;
839 return (new ? 0 : -ENOMEM);
840 }
841 EXPORT_SYMBOL_GPL(ip6_dst_blackhole);
842
843 /*
844 * Destination cache support functions
845 */
846
847 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
848 {
849 struct rt6_info *rt;
850
851 rt = (struct rt6_info *) dst;
852
853 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
854 return dst;
855
856 return NULL;
857 }
858
859 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
860 {
861 struct rt6_info *rt = (struct rt6_info *) dst;
862
863 if (rt) {
864 if (rt->rt6i_flags & RTF_CACHE)
865 ip6_del_rt(rt);
866 else
867 dst_release(dst);
868 }
869 return NULL;
870 }
871
872 static void ip6_link_failure(struct sk_buff *skb)
873 {
874 struct rt6_info *rt;
875
876 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
877
878 rt = (struct rt6_info *) skb->dst;
879 if (rt) {
880 if (rt->rt6i_flags&RTF_CACHE) {
881 dst_set_expires(&rt->u.dst, 0);
882 rt->rt6i_flags |= RTF_EXPIRES;
883 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
884 rt->rt6i_node->fn_sernum = -1;
885 }
886 }
887
888 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
889 {
890 struct rt6_info *rt6 = (struct rt6_info*)dst;
891
892 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
893 rt6->rt6i_flags |= RTF_MODIFIED;
894 if (mtu < IPV6_MIN_MTU) {
895 mtu = IPV6_MIN_MTU;
896 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
897 }
898 dst->metrics[RTAX_MTU-1] = mtu;
899 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
900 }
901 }
902
903 static int ipv6_get_mtu(struct net_device *dev);
904
905 static inline unsigned int ipv6_advmss(struct net *net, unsigned int mtu)
906 {
907 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
908
909 if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
910 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
911
912 /*
913 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
914 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
915 * IPV6_MAXPLEN is also valid and means: "any MSS,
916 * rely only on pmtu discovery"
917 */
918 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
919 mtu = IPV6_MAXPLEN;
920 return mtu;
921 }
922
923 static struct dst_entry *icmp6_dst_gc_list;
924 static DEFINE_SPINLOCK(icmp6_dst_lock);
925
926 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
927 struct neighbour *neigh,
928 const struct in6_addr *addr)
929 {
930 struct rt6_info *rt;
931 struct inet6_dev *idev = in6_dev_get(dev);
932 struct net *net = dev_net(dev);
933
934 if (unlikely(idev == NULL))
935 return NULL;
936
937 rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops);
938 if (unlikely(rt == NULL)) {
939 in6_dev_put(idev);
940 goto out;
941 }
942
943 dev_hold(dev);
944 if (neigh)
945 neigh_hold(neigh);
946 else
947 neigh = ndisc_get_neigh(dev, addr);
948
949 rt->rt6i_dev = dev;
950 rt->rt6i_idev = idev;
951 rt->rt6i_nexthop = neigh;
952 atomic_set(&rt->u.dst.__refcnt, 1);
953 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
954 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
955 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst));
956 rt->u.dst.output = ip6_output;
957
958 #if 0 /* there's no chance to use these for ndisc */
959 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
960 ? DST_HOST
961 : 0;
962 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
963 rt->rt6i_dst.plen = 128;
964 #endif
965
966 spin_lock_bh(&icmp6_dst_lock);
967 rt->u.dst.next = icmp6_dst_gc_list;
968 icmp6_dst_gc_list = &rt->u.dst;
969 spin_unlock_bh(&icmp6_dst_lock);
970
971 fib6_force_start_gc(net);
972
973 out:
974 return &rt->u.dst;
975 }
976
977 int icmp6_dst_gc(int *more)
978 {
979 struct dst_entry *dst, *next, **pprev;
980 int freed;
981
982 next = NULL;
983 freed = 0;
984
985 spin_lock_bh(&icmp6_dst_lock);
986 pprev = &icmp6_dst_gc_list;
987
988 while ((dst = *pprev) != NULL) {
989 if (!atomic_read(&dst->__refcnt)) {
990 *pprev = dst->next;
991 dst_free(dst);
992 freed++;
993 } else {
994 pprev = &dst->next;
995 (*more)++;
996 }
997 }
998
999 spin_unlock_bh(&icmp6_dst_lock);
1000
1001 return freed;
1002 }
1003
1004 static int ip6_dst_gc(struct dst_ops *ops)
1005 {
1006 unsigned long now = jiffies;
1007 struct net *net = ops->dst_net;
1008 int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1009 int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1010 int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1011 int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1012 unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1013
1014 if (time_after(rt_last_gc + rt_min_interval, now) &&
1015 atomic_read(&ops->entries) <= rt_max_size)
1016 goto out;
1017
1018 net->ipv6.ip6_rt_gc_expire++;
1019 fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net);
1020 net->ipv6.ip6_rt_last_gc = now;
1021 if (atomic_read(&ops->entries) < ops->gc_thresh)
1022 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1023 out:
1024 net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1025 return (atomic_read(&ops->entries) > rt_max_size);
1026 }
1027
1028 /* Clean host part of a prefix. Not necessary in radix tree,
1029 but results in cleaner routing tables.
1030
1031 Remove it only when all the things will work!
1032 */
1033
1034 static int ipv6_get_mtu(struct net_device *dev)
1035 {
1036 int mtu = IPV6_MIN_MTU;
1037 struct inet6_dev *idev;
1038
1039 idev = in6_dev_get(dev);
1040 if (idev) {
1041 mtu = idev->cnf.mtu6;
1042 in6_dev_put(idev);
1043 }
1044 return mtu;
1045 }
1046
1047 int ip6_dst_hoplimit(struct dst_entry *dst)
1048 {
1049 int hoplimit = dst_metric(dst, RTAX_HOPLIMIT);
1050 if (hoplimit < 0) {
1051 struct net_device *dev = dst->dev;
1052 struct inet6_dev *idev = in6_dev_get(dev);
1053 if (idev) {
1054 hoplimit = idev->cnf.hop_limit;
1055 in6_dev_put(idev);
1056 } else
1057 hoplimit = ipv6_devconf.hop_limit;
1058 }
1059 return hoplimit;
1060 }
1061
1062 /*
1063 *
1064 */
1065
1066 int ip6_route_add(struct fib6_config *cfg)
1067 {
1068 int err;
1069 struct net *net = cfg->fc_nlinfo.nl_net;
1070 struct rt6_info *rt = NULL;
1071 struct net_device *dev = NULL;
1072 struct inet6_dev *idev = NULL;
1073 struct fib6_table *table;
1074 int addr_type;
1075
1076 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1077 return -EINVAL;
1078 #ifndef CONFIG_IPV6_SUBTREES
1079 if (cfg->fc_src_len)
1080 return -EINVAL;
1081 #endif
1082 if (cfg->fc_ifindex) {
1083 err = -ENODEV;
1084 dev = dev_get_by_index(net, cfg->fc_ifindex);
1085 if (!dev)
1086 goto out;
1087 idev = in6_dev_get(dev);
1088 if (!idev)
1089 goto out;
1090 }
1091
1092 if (cfg->fc_metric == 0)
1093 cfg->fc_metric = IP6_RT_PRIO_USER;
1094
1095 table = fib6_new_table(net, cfg->fc_table);
1096 if (table == NULL) {
1097 err = -ENOBUFS;
1098 goto out;
1099 }
1100
1101 rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops);
1102
1103 if (rt == NULL) {
1104 err = -ENOMEM;
1105 goto out;
1106 }
1107
1108 rt->u.dst.obsolete = -1;
1109 rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1110
1111 if (cfg->fc_protocol == RTPROT_UNSPEC)
1112 cfg->fc_protocol = RTPROT_BOOT;
1113 rt->rt6i_protocol = cfg->fc_protocol;
1114
1115 addr_type = ipv6_addr_type(&cfg->fc_dst);
1116
1117 if (addr_type & IPV6_ADDR_MULTICAST)
1118 rt->u.dst.input = ip6_mc_input;
1119 else
1120 rt->u.dst.input = ip6_forward;
1121
1122 rt->u.dst.output = ip6_output;
1123
1124 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1125 rt->rt6i_dst.plen = cfg->fc_dst_len;
1126 if (rt->rt6i_dst.plen == 128)
1127 rt->u.dst.flags = DST_HOST;
1128
1129 #ifdef CONFIG_IPV6_SUBTREES
1130 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1131 rt->rt6i_src.plen = cfg->fc_src_len;
1132 #endif
1133
1134 rt->rt6i_metric = cfg->fc_metric;
1135
1136 /* We cannot add true routes via loopback here,
1137 they would result in kernel looping; promote them to reject routes
1138 */
1139 if ((cfg->fc_flags & RTF_REJECT) ||
1140 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1141 /* hold loopback dev/idev if we haven't done so. */
1142 if (dev != net->loopback_dev) {
1143 if (dev) {
1144 dev_put(dev);
1145 in6_dev_put(idev);
1146 }
1147 dev = net->loopback_dev;
1148 dev_hold(dev);
1149 idev = in6_dev_get(dev);
1150 if (!idev) {
1151 err = -ENODEV;
1152 goto out;
1153 }
1154 }
1155 rt->u.dst.output = ip6_pkt_discard_out;
1156 rt->u.dst.input = ip6_pkt_discard;
1157 rt->u.dst.error = -ENETUNREACH;
1158 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1159 goto install_route;
1160 }
1161
1162 if (cfg->fc_flags & RTF_GATEWAY) {
1163 struct in6_addr *gw_addr;
1164 int gwa_type;
1165
1166 gw_addr = &cfg->fc_gateway;
1167 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1168 gwa_type = ipv6_addr_type(gw_addr);
1169
1170 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1171 struct rt6_info *grt;
1172
1173 /* IPv6 strictly inhibits using not link-local
1174 addresses as nexthop address.
1175 Otherwise, router will not able to send redirects.
1176 It is very good, but in some (rare!) circumstances
1177 (SIT, PtP, NBMA NOARP links) it is handy to allow
1178 some exceptions. --ANK
1179 */
1180 err = -EINVAL;
1181 if (!(gwa_type&IPV6_ADDR_UNICAST))
1182 goto out;
1183
1184 grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1185
1186 err = -EHOSTUNREACH;
1187 if (grt == NULL)
1188 goto out;
1189 if (dev) {
1190 if (dev != grt->rt6i_dev) {
1191 dst_release(&grt->u.dst);
1192 goto out;
1193 }
1194 } else {
1195 dev = grt->rt6i_dev;
1196 idev = grt->rt6i_idev;
1197 dev_hold(dev);
1198 in6_dev_hold(grt->rt6i_idev);
1199 }
1200 if (!(grt->rt6i_flags&RTF_GATEWAY))
1201 err = 0;
1202 dst_release(&grt->u.dst);
1203
1204 if (err)
1205 goto out;
1206 }
1207 err = -EINVAL;
1208 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1209 goto out;
1210 }
1211
1212 err = -ENODEV;
1213 if (dev == NULL)
1214 goto out;
1215
1216 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1217 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1218 if (IS_ERR(rt->rt6i_nexthop)) {
1219 err = PTR_ERR(rt->rt6i_nexthop);
1220 rt->rt6i_nexthop = NULL;
1221 goto out;
1222 }
1223 }
1224
1225 rt->rt6i_flags = cfg->fc_flags;
1226
1227 install_route:
1228 if (cfg->fc_mx) {
1229 struct nlattr *nla;
1230 int remaining;
1231
1232 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1233 int type = nla_type(nla);
1234
1235 if (type) {
1236 if (type > RTAX_MAX) {
1237 err = -EINVAL;
1238 goto out;
1239 }
1240
1241 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1242 }
1243 }
1244 }
1245
1246 if (dst_metric(&rt->u.dst, RTAX_HOPLIMIT) == 0)
1247 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1248 if (!dst_metric(&rt->u.dst, RTAX_MTU))
1249 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1250 if (!dst_metric(&rt->u.dst, RTAX_ADVMSS))
1251 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst));
1252 rt->u.dst.dev = dev;
1253 rt->rt6i_idev = idev;
1254 rt->rt6i_table = table;
1255
1256 cfg->fc_nlinfo.nl_net = dev_net(dev);
1257
1258 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1259
1260 out:
1261 if (dev)
1262 dev_put(dev);
1263 if (idev)
1264 in6_dev_put(idev);
1265 if (rt)
1266 dst_free(&rt->u.dst);
1267 return err;
1268 }
1269
1270 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1271 {
1272 int err;
1273 struct fib6_table *table;
1274 struct net *net = dev_net(rt->rt6i_dev);
1275
1276 if (rt == net->ipv6.ip6_null_entry)
1277 return -ENOENT;
1278
1279 table = rt->rt6i_table;
1280 write_lock_bh(&table->tb6_lock);
1281
1282 err = fib6_del(rt, info);
1283 dst_release(&rt->u.dst);
1284
1285 write_unlock_bh(&table->tb6_lock);
1286
1287 return err;
1288 }
1289
1290 int ip6_del_rt(struct rt6_info *rt)
1291 {
1292 struct nl_info info = {
1293 .nl_net = dev_net(rt->rt6i_dev),
1294 };
1295 return __ip6_del_rt(rt, &info);
1296 }
1297
1298 static int ip6_route_del(struct fib6_config *cfg)
1299 {
1300 struct fib6_table *table;
1301 struct fib6_node *fn;
1302 struct rt6_info *rt;
1303 int err = -ESRCH;
1304
1305 table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
1306 if (table == NULL)
1307 return err;
1308
1309 read_lock_bh(&table->tb6_lock);
1310
1311 fn = fib6_locate(&table->tb6_root,
1312 &cfg->fc_dst, cfg->fc_dst_len,
1313 &cfg->fc_src, cfg->fc_src_len);
1314
1315 if (fn) {
1316 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1317 if (cfg->fc_ifindex &&
1318 (rt->rt6i_dev == NULL ||
1319 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1320 continue;
1321 if (cfg->fc_flags & RTF_GATEWAY &&
1322 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1323 continue;
1324 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1325 continue;
1326 dst_hold(&rt->u.dst);
1327 read_unlock_bh(&table->tb6_lock);
1328
1329 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1330 }
1331 }
1332 read_unlock_bh(&table->tb6_lock);
1333
1334 return err;
1335 }
1336
1337 /*
1338 * Handle redirects
1339 */
1340 struct ip6rd_flowi {
1341 struct flowi fl;
1342 struct in6_addr gateway;
1343 };
1344
1345 static struct rt6_info *__ip6_route_redirect(struct net *net,
1346 struct fib6_table *table,
1347 struct flowi *fl,
1348 int flags)
1349 {
1350 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1351 struct rt6_info *rt;
1352 struct fib6_node *fn;
1353
1354 /*
1355 * Get the "current" route for this destination and
1356 * check if the redirect has come from approriate router.
1357 *
1358 * RFC 2461 specifies that redirects should only be
1359 * accepted if they come from the nexthop to the target.
1360 * Due to the way the routes are chosen, this notion
1361 * is a bit fuzzy and one might need to check all possible
1362 * routes.
1363 */
1364
1365 read_lock_bh(&table->tb6_lock);
1366 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1367 restart:
1368 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1369 /*
1370 * Current route is on-link; redirect is always invalid.
1371 *
1372 * Seems, previous statement is not true. It could
1373 * be node, which looks for us as on-link (f.e. proxy ndisc)
1374 * But then router serving it might decide, that we should
1375 * know truth 8)8) --ANK (980726).
1376 */
1377 if (rt6_check_expired(rt))
1378 continue;
1379 if (!(rt->rt6i_flags & RTF_GATEWAY))
1380 continue;
1381 if (fl->oif != rt->rt6i_dev->ifindex)
1382 continue;
1383 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1384 continue;
1385 break;
1386 }
1387
1388 if (!rt)
1389 rt = net->ipv6.ip6_null_entry;
1390 BACKTRACK(net, &fl->fl6_src);
1391 out:
1392 dst_hold(&rt->u.dst);
1393
1394 read_unlock_bh(&table->tb6_lock);
1395
1396 return rt;
1397 };
1398
1399 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1400 struct in6_addr *src,
1401 struct in6_addr *gateway,
1402 struct net_device *dev)
1403 {
1404 int flags = RT6_LOOKUP_F_HAS_SADDR;
1405 struct net *net = dev_net(dev);
1406 struct ip6rd_flowi rdfl = {
1407 .fl = {
1408 .oif = dev->ifindex,
1409 .nl_u = {
1410 .ip6_u = {
1411 .daddr = *dest,
1412 .saddr = *src,
1413 },
1414 },
1415 },
1416 .gateway = *gateway,
1417 };
1418
1419 if (rt6_need_strict(dest))
1420 flags |= RT6_LOOKUP_F_IFACE;
1421
1422 return (struct rt6_info *)fib6_rule_lookup(net, (struct flowi *)&rdfl,
1423 flags, __ip6_route_redirect);
1424 }
1425
1426 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1427 struct in6_addr *saddr,
1428 struct neighbour *neigh, u8 *lladdr, int on_link)
1429 {
1430 struct rt6_info *rt, *nrt = NULL;
1431 struct netevent_redirect netevent;
1432 struct net *net = dev_net(neigh->dev);
1433
1434 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1435
1436 if (rt == net->ipv6.ip6_null_entry) {
1437 if (net_ratelimit())
1438 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1439 "for redirect target\n");
1440 goto out;
1441 }
1442
1443 /*
1444 * We have finally decided to accept it.
1445 */
1446
1447 neigh_update(neigh, lladdr, NUD_STALE,
1448 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1449 NEIGH_UPDATE_F_OVERRIDE|
1450 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1451 NEIGH_UPDATE_F_ISROUTER))
1452 );
1453
1454 /*
1455 * Redirect received -> path was valid.
1456 * Look, redirects are sent only in response to data packets,
1457 * so that this nexthop apparently is reachable. --ANK
1458 */
1459 dst_confirm(&rt->u.dst);
1460
1461 /* Duplicate redirect: silently ignore. */
1462 if (neigh == rt->u.dst.neighbour)
1463 goto out;
1464
1465 nrt = ip6_rt_copy(rt);
1466 if (nrt == NULL)
1467 goto out;
1468
1469 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1470 if (on_link)
1471 nrt->rt6i_flags &= ~RTF_GATEWAY;
1472
1473 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1474 nrt->rt6i_dst.plen = 128;
1475 nrt->u.dst.flags |= DST_HOST;
1476
1477 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1478 nrt->rt6i_nexthop = neigh_clone(neigh);
1479 /* Reset pmtu, it may be better */
1480 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1481 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dev_net(neigh->dev),
1482 dst_mtu(&nrt->u.dst));
1483
1484 if (ip6_ins_rt(nrt))
1485 goto out;
1486
1487 netevent.old = &rt->u.dst;
1488 netevent.new = &nrt->u.dst;
1489 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1490
1491 if (rt->rt6i_flags&RTF_CACHE) {
1492 ip6_del_rt(rt);
1493 return;
1494 }
1495
1496 out:
1497 dst_release(&rt->u.dst);
1498 return;
1499 }
1500
1501 /*
1502 * Handle ICMP "packet too big" messages
1503 * i.e. Path MTU discovery
1504 */
1505
1506 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1507 struct net_device *dev, u32 pmtu)
1508 {
1509 struct rt6_info *rt, *nrt;
1510 struct net *net = dev_net(dev);
1511 int allfrag = 0;
1512
1513 rt = rt6_lookup(net, daddr, saddr, dev->ifindex, 0);
1514 if (rt == NULL)
1515 return;
1516
1517 if (pmtu >= dst_mtu(&rt->u.dst))
1518 goto out;
1519
1520 if (pmtu < IPV6_MIN_MTU) {
1521 /*
1522 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1523 * MTU (1280) and a fragment header should always be included
1524 * after a node receiving Too Big message reporting PMTU is
1525 * less than the IPv6 Minimum Link MTU.
1526 */
1527 pmtu = IPV6_MIN_MTU;
1528 allfrag = 1;
1529 }
1530
1531 /* New mtu received -> path was valid.
1532 They are sent only in response to data packets,
1533 so that this nexthop apparently is reachable. --ANK
1534 */
1535 dst_confirm(&rt->u.dst);
1536
1537 /* Host route. If it is static, it would be better
1538 not to override it, but add new one, so that
1539 when cache entry will expire old pmtu
1540 would return automatically.
1541 */
1542 if (rt->rt6i_flags & RTF_CACHE) {
1543 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1544 if (allfrag)
1545 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1546 dst_set_expires(&rt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1547 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1548 goto out;
1549 }
1550
1551 /* Network route.
1552 Two cases are possible:
1553 1. It is connected route. Action: COW
1554 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1555 */
1556 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1557 nrt = rt6_alloc_cow(rt, daddr, saddr);
1558 else
1559 nrt = rt6_alloc_clone(rt, daddr);
1560
1561 if (nrt) {
1562 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1563 if (allfrag)
1564 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1565
1566 /* According to RFC 1981, detecting PMTU increase shouldn't be
1567 * happened within 5 mins, the recommended timer is 10 mins.
1568 * Here this route expiration time is set to ip6_rt_mtu_expires
1569 * which is 10 mins. After 10 mins the decreased pmtu is expired
1570 * and detecting PMTU increase will be automatically happened.
1571 */
1572 dst_set_expires(&nrt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires);
1573 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1574
1575 ip6_ins_rt(nrt);
1576 }
1577 out:
1578 dst_release(&rt->u.dst);
1579 }
1580
1581 /*
1582 * Misc support functions
1583 */
1584
1585 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1586 {
1587 struct net *net = dev_net(ort->rt6i_dev);
1588 struct rt6_info *rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops);
1589
1590 if (rt) {
1591 rt->u.dst.input = ort->u.dst.input;
1592 rt->u.dst.output = ort->u.dst.output;
1593
1594 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1595 rt->u.dst.error = ort->u.dst.error;
1596 rt->u.dst.dev = ort->u.dst.dev;
1597 if (rt->u.dst.dev)
1598 dev_hold(rt->u.dst.dev);
1599 rt->rt6i_idev = ort->rt6i_idev;
1600 if (rt->rt6i_idev)
1601 in6_dev_hold(rt->rt6i_idev);
1602 rt->u.dst.lastuse = jiffies;
1603 rt->rt6i_expires = 0;
1604
1605 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1606 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1607 rt->rt6i_metric = 0;
1608
1609 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1610 #ifdef CONFIG_IPV6_SUBTREES
1611 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1612 #endif
1613 rt->rt6i_table = ort->rt6i_table;
1614 }
1615 return rt;
1616 }
1617
1618 #ifdef CONFIG_IPV6_ROUTE_INFO
1619 static struct rt6_info *rt6_get_route_info(struct net *net,
1620 struct in6_addr *prefix, int prefixlen,
1621 struct in6_addr *gwaddr, int ifindex)
1622 {
1623 struct fib6_node *fn;
1624 struct rt6_info *rt = NULL;
1625 struct fib6_table *table;
1626
1627 table = fib6_get_table(net, RT6_TABLE_INFO);
1628 if (table == NULL)
1629 return NULL;
1630
1631 write_lock_bh(&table->tb6_lock);
1632 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1633 if (!fn)
1634 goto out;
1635
1636 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1637 if (rt->rt6i_dev->ifindex != ifindex)
1638 continue;
1639 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1640 continue;
1641 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1642 continue;
1643 dst_hold(&rt->u.dst);
1644 break;
1645 }
1646 out:
1647 write_unlock_bh(&table->tb6_lock);
1648 return rt;
1649 }
1650
1651 static struct rt6_info *rt6_add_route_info(struct net *net,
1652 struct in6_addr *prefix, int prefixlen,
1653 struct in6_addr *gwaddr, int ifindex,
1654 unsigned pref)
1655 {
1656 struct fib6_config cfg = {
1657 .fc_table = RT6_TABLE_INFO,
1658 .fc_metric = IP6_RT_PRIO_USER,
1659 .fc_ifindex = ifindex,
1660 .fc_dst_len = prefixlen,
1661 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1662 RTF_UP | RTF_PREF(pref),
1663 .fc_nlinfo.pid = 0,
1664 .fc_nlinfo.nlh = NULL,
1665 .fc_nlinfo.nl_net = net,
1666 };
1667
1668 ipv6_addr_copy(&cfg.fc_dst, prefix);
1669 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1670
1671 /* We should treat it as a default route if prefix length is 0. */
1672 if (!prefixlen)
1673 cfg.fc_flags |= RTF_DEFAULT;
1674
1675 ip6_route_add(&cfg);
1676
1677 return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
1678 }
1679 #endif
1680
1681 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1682 {
1683 struct rt6_info *rt;
1684 struct fib6_table *table;
1685
1686 table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
1687 if (table == NULL)
1688 return NULL;
1689
1690 write_lock_bh(&table->tb6_lock);
1691 for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) {
1692 if (dev == rt->rt6i_dev &&
1693 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1694 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1695 break;
1696 }
1697 if (rt)
1698 dst_hold(&rt->u.dst);
1699 write_unlock_bh(&table->tb6_lock);
1700 return rt;
1701 }
1702
1703 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1704 struct net_device *dev,
1705 unsigned int pref)
1706 {
1707 struct fib6_config cfg = {
1708 .fc_table = RT6_TABLE_DFLT,
1709 .fc_metric = IP6_RT_PRIO_USER,
1710 .fc_ifindex = dev->ifindex,
1711 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1712 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1713 .fc_nlinfo.pid = 0,
1714 .fc_nlinfo.nlh = NULL,
1715 .fc_nlinfo.nl_net = dev_net(dev),
1716 };
1717
1718 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1719
1720 ip6_route_add(&cfg);
1721
1722 return rt6_get_dflt_router(gwaddr, dev);
1723 }
1724
1725 void rt6_purge_dflt_routers(struct net *net)
1726 {
1727 struct rt6_info *rt;
1728 struct fib6_table *table;
1729
1730 /* NOTE: Keep consistent with rt6_get_dflt_router */
1731 table = fib6_get_table(net, RT6_TABLE_DFLT);
1732 if (table == NULL)
1733 return;
1734
1735 restart:
1736 read_lock_bh(&table->tb6_lock);
1737 for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) {
1738 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1739 dst_hold(&rt->u.dst);
1740 read_unlock_bh(&table->tb6_lock);
1741 ip6_del_rt(rt);
1742 goto restart;
1743 }
1744 }
1745 read_unlock_bh(&table->tb6_lock);
1746 }
1747
1748 static void rtmsg_to_fib6_config(struct net *net,
1749 struct in6_rtmsg *rtmsg,
1750 struct fib6_config *cfg)
1751 {
1752 memset(cfg, 0, sizeof(*cfg));
1753
1754 cfg->fc_table = RT6_TABLE_MAIN;
1755 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1756 cfg->fc_metric = rtmsg->rtmsg_metric;
1757 cfg->fc_expires = rtmsg->rtmsg_info;
1758 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1759 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1760 cfg->fc_flags = rtmsg->rtmsg_flags;
1761
1762 cfg->fc_nlinfo.nl_net = net;
1763
1764 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1765 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1766 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1767 }
1768
1769 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
1770 {
1771 struct fib6_config cfg;
1772 struct in6_rtmsg rtmsg;
1773 int err;
1774
1775 switch(cmd) {
1776 case SIOCADDRT: /* Add a route */
1777 case SIOCDELRT: /* Delete a route */
1778 if (!capable(CAP_NET_ADMIN))
1779 return -EPERM;
1780 err = copy_from_user(&rtmsg, arg,
1781 sizeof(struct in6_rtmsg));
1782 if (err)
1783 return -EFAULT;
1784
1785 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
1786
1787 rtnl_lock();
1788 switch (cmd) {
1789 case SIOCADDRT:
1790 err = ip6_route_add(&cfg);
1791 break;
1792 case SIOCDELRT:
1793 err = ip6_route_del(&cfg);
1794 break;
1795 default:
1796 err = -EINVAL;
1797 }
1798 rtnl_unlock();
1799
1800 return err;
1801 }
1802
1803 return -EINVAL;
1804 }
1805
1806 /*
1807 * Drop the packet on the floor
1808 */
1809
1810 static int ip6_pkt_drop(struct sk_buff *skb, int code, int ipstats_mib_noroutes)
1811 {
1812 int type;
1813 switch (ipstats_mib_noroutes) {
1814 case IPSTATS_MIB_INNOROUTES:
1815 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1816 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) {
1817 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS);
1818 break;
1819 }
1820 /* FALLTHROUGH */
1821 case IPSTATS_MIB_OUTNOROUTES:
1822 IP6_INC_STATS(ip6_dst_idev(skb->dst), ipstats_mib_noroutes);
1823 break;
1824 }
1825 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
1826 kfree_skb(skb);
1827 return 0;
1828 }
1829
1830 static int ip6_pkt_discard(struct sk_buff *skb)
1831 {
1832 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1833 }
1834
1835 static int ip6_pkt_discard_out(struct sk_buff *skb)
1836 {
1837 skb->dev = skb->dst->dev;
1838 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
1839 }
1840
1841 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1842
1843 static int ip6_pkt_prohibit(struct sk_buff *skb)
1844 {
1845 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1846 }
1847
1848 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1849 {
1850 skb->dev = skb->dst->dev;
1851 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1852 }
1853
1854 #endif
1855
1856 /*
1857 * Allocate a dst for local (unicast / anycast) address.
1858 */
1859
1860 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1861 const struct in6_addr *addr,
1862 int anycast)
1863 {
1864 struct net *net = dev_net(idev->dev);
1865 struct rt6_info *rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops);
1866
1867 if (rt == NULL)
1868 return ERR_PTR(-ENOMEM);
1869
1870 dev_hold(net->loopback_dev);
1871 in6_dev_hold(idev);
1872
1873 rt->u.dst.flags = DST_HOST;
1874 rt->u.dst.input = ip6_input;
1875 rt->u.dst.output = ip6_output;
1876 rt->rt6i_dev = net->loopback_dev;
1877 rt->rt6i_idev = idev;
1878 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1879 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst));
1880 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1881 rt->u.dst.obsolete = -1;
1882
1883 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1884 if (anycast)
1885 rt->rt6i_flags |= RTF_ANYCAST;
1886 else
1887 rt->rt6i_flags |= RTF_LOCAL;
1888 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1889 if (rt->rt6i_nexthop == NULL) {
1890 dst_free(&rt->u.dst);
1891 return ERR_PTR(-ENOMEM);
1892 }
1893
1894 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1895 rt->rt6i_dst.plen = 128;
1896 rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
1897
1898 atomic_set(&rt->u.dst.__refcnt, 1);
1899
1900 return rt;
1901 }
1902
1903 struct arg_dev_net {
1904 struct net_device *dev;
1905 struct net *net;
1906 };
1907
1908 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1909 {
1910 struct net_device *dev = ((struct arg_dev_net *)arg)->dev;
1911 struct net *net = ((struct arg_dev_net *)arg)->net;
1912
1913 if (((void *)rt->rt6i_dev == dev || dev == NULL) &&
1914 rt != net->ipv6.ip6_null_entry) {
1915 RT6_TRACE("deleted by ifdown %p\n", rt);
1916 return -1;
1917 }
1918 return 0;
1919 }
1920
1921 void rt6_ifdown(struct net *net, struct net_device *dev)
1922 {
1923 struct arg_dev_net adn = {
1924 .dev = dev,
1925 .net = net,
1926 };
1927
1928 fib6_clean_all(net, fib6_ifdown, 0, &adn);
1929 }
1930
1931 struct rt6_mtu_change_arg
1932 {
1933 struct net_device *dev;
1934 unsigned mtu;
1935 };
1936
1937 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1938 {
1939 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1940 struct inet6_dev *idev;
1941 struct net *net = dev_net(arg->dev);
1942
1943 /* In IPv6 pmtu discovery is not optional,
1944 so that RTAX_MTU lock cannot disable it.
1945 We still use this lock to block changes
1946 caused by addrconf/ndisc.
1947 */
1948
1949 idev = __in6_dev_get(arg->dev);
1950 if (idev == NULL)
1951 return 0;
1952
1953 /* For administrative MTU increase, there is no way to discover
1954 IPv6 PMTU increase, so PMTU increase should be updated here.
1955 Since RFC 1981 doesn't include administrative MTU increase
1956 update PMTU increase is a MUST. (i.e. jumbo frame)
1957 */
1958 /*
1959 If new MTU is less than route PMTU, this new MTU will be the
1960 lowest MTU in the path, update the route PMTU to reflect PMTU
1961 decreases; if new MTU is greater than route PMTU, and the
1962 old MTU is the lowest MTU in the path, update the route PMTU
1963 to reflect the increase. In this case if the other nodes' MTU
1964 also have the lowest MTU, TOO BIG MESSAGE will be lead to
1965 PMTU discouvery.
1966 */
1967 if (rt->rt6i_dev == arg->dev &&
1968 !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1969 (dst_mtu(&rt->u.dst) >= arg->mtu ||
1970 (dst_mtu(&rt->u.dst) < arg->mtu &&
1971 dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) {
1972 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1973 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, arg->mtu);
1974 }
1975 return 0;
1976 }
1977
1978 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
1979 {
1980 struct rt6_mtu_change_arg arg = {
1981 .dev = dev,
1982 .mtu = mtu,
1983 };
1984
1985 fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg);
1986 }
1987
1988 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
1989 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
1990 [RTA_OIF] = { .type = NLA_U32 },
1991 [RTA_IIF] = { .type = NLA_U32 },
1992 [RTA_PRIORITY] = { .type = NLA_U32 },
1993 [RTA_METRICS] = { .type = NLA_NESTED },
1994 };
1995
1996 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
1997 struct fib6_config *cfg)
1998 {
1999 struct rtmsg *rtm;
2000 struct nlattr *tb[RTA_MAX+1];
2001 int err;
2002
2003 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2004 if (err < 0)
2005 goto errout;
2006
2007 err = -EINVAL;
2008 rtm = nlmsg_data(nlh);
2009 memset(cfg, 0, sizeof(*cfg));
2010
2011 cfg->fc_table = rtm->rtm_table;
2012 cfg->fc_dst_len = rtm->rtm_dst_len;
2013 cfg->fc_src_len = rtm->rtm_src_len;
2014 cfg->fc_flags = RTF_UP;
2015 cfg->fc_protocol = rtm->rtm_protocol;
2016
2017 if (rtm->rtm_type == RTN_UNREACHABLE)
2018 cfg->fc_flags |= RTF_REJECT;
2019
2020 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
2021 cfg->fc_nlinfo.nlh = nlh;
2022 cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2023
2024 if (tb[RTA_GATEWAY]) {
2025 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2026 cfg->fc_flags |= RTF_GATEWAY;
2027 }
2028
2029 if (tb[RTA_DST]) {
2030 int plen = (rtm->rtm_dst_len + 7) >> 3;
2031
2032 if (nla_len(tb[RTA_DST]) < plen)
2033 goto errout;
2034
2035 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2036 }
2037
2038 if (tb[RTA_SRC]) {
2039 int plen = (rtm->rtm_src_len + 7) >> 3;
2040
2041 if (nla_len(tb[RTA_SRC]) < plen)
2042 goto errout;
2043
2044 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2045 }
2046
2047 if (tb[RTA_OIF])
2048 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2049
2050 if (tb[RTA_PRIORITY])
2051 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2052
2053 if (tb[RTA_METRICS]) {
2054 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2055 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2056 }
2057
2058 if (tb[RTA_TABLE])
2059 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2060
2061 err = 0;
2062 errout:
2063 return err;
2064 }
2065
2066 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2067 {
2068 struct fib6_config cfg;
2069 int err;
2070
2071 err = rtm_to_fib6_config(skb, nlh, &cfg);
2072 if (err < 0)
2073 return err;
2074
2075 return ip6_route_del(&cfg);
2076 }
2077
2078 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2079 {
2080 struct fib6_config cfg;
2081 int err;
2082
2083 err = rtm_to_fib6_config(skb, nlh, &cfg);
2084 if (err < 0)
2085 return err;
2086
2087 return ip6_route_add(&cfg);
2088 }
2089
2090 static inline size_t rt6_nlmsg_size(void)
2091 {
2092 return NLMSG_ALIGN(sizeof(struct rtmsg))
2093 + nla_total_size(16) /* RTA_SRC */
2094 + nla_total_size(16) /* RTA_DST */
2095 + nla_total_size(16) /* RTA_GATEWAY */
2096 + nla_total_size(16) /* RTA_PREFSRC */
2097 + nla_total_size(4) /* RTA_TABLE */
2098 + nla_total_size(4) /* RTA_IIF */
2099 + nla_total_size(4) /* RTA_OIF */
2100 + nla_total_size(4) /* RTA_PRIORITY */
2101 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2102 + nla_total_size(sizeof(struct rta_cacheinfo));
2103 }
2104
2105 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2106 struct in6_addr *dst, struct in6_addr *src,
2107 int iif, int type, u32 pid, u32 seq,
2108 int prefix, int nowait, unsigned int flags)
2109 {
2110 struct rtmsg *rtm;
2111 struct nlmsghdr *nlh;
2112 long expires;
2113 u32 table;
2114
2115 if (prefix) { /* user wants prefix routes only */
2116 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2117 /* success since this is not a prefix route */
2118 return 1;
2119 }
2120 }
2121
2122 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2123 if (nlh == NULL)
2124 return -EMSGSIZE;
2125
2126 rtm = nlmsg_data(nlh);
2127 rtm->rtm_family = AF_INET6;
2128 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2129 rtm->rtm_src_len = rt->rt6i_src.plen;
2130 rtm->rtm_tos = 0;
2131 if (rt->rt6i_table)
2132 table = rt->rt6i_table->tb6_id;
2133 else
2134 table = RT6_TABLE_UNSPEC;
2135 rtm->rtm_table = table;
2136 NLA_PUT_U32(skb, RTA_TABLE, table);
2137 if (rt->rt6i_flags&RTF_REJECT)
2138 rtm->rtm_type = RTN_UNREACHABLE;
2139 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2140 rtm->rtm_type = RTN_LOCAL;
2141 else
2142 rtm->rtm_type = RTN_UNICAST;
2143 rtm->rtm_flags = 0;
2144 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2145 rtm->rtm_protocol = rt->rt6i_protocol;
2146 if (rt->rt6i_flags&RTF_DYNAMIC)
2147 rtm->rtm_protocol = RTPROT_REDIRECT;
2148 else if (rt->rt6i_flags & RTF_ADDRCONF)
2149 rtm->rtm_protocol = RTPROT_KERNEL;
2150 else if (rt->rt6i_flags&RTF_DEFAULT)
2151 rtm->rtm_protocol = RTPROT_RA;
2152
2153 if (rt->rt6i_flags&RTF_CACHE)
2154 rtm->rtm_flags |= RTM_F_CLONED;
2155
2156 if (dst) {
2157 NLA_PUT(skb, RTA_DST, 16, dst);
2158 rtm->rtm_dst_len = 128;
2159 } else if (rtm->rtm_dst_len)
2160 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2161 #ifdef CONFIG_IPV6_SUBTREES
2162 if (src) {
2163 NLA_PUT(skb, RTA_SRC, 16, src);
2164 rtm->rtm_src_len = 128;
2165 } else if (rtm->rtm_src_len)
2166 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2167 #endif
2168 if (iif) {
2169 #ifdef CONFIG_IPV6_MROUTE
2170 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
2171 int err = ip6mr_get_route(skb, rtm, nowait);
2172 if (err <= 0) {
2173 if (!nowait) {
2174 if (err == 0)
2175 return 0;
2176 goto nla_put_failure;
2177 } else {
2178 if (err == -EMSGSIZE)
2179 goto nla_put_failure;
2180 }
2181 }
2182 } else
2183 #endif
2184 NLA_PUT_U32(skb, RTA_IIF, iif);
2185 } else if (dst) {
2186 struct in6_addr saddr_buf;
2187 if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev,
2188 dst, 0, &saddr_buf) == 0)
2189 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2190 }
2191
2192 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2193 goto nla_put_failure;
2194
2195 if (rt->u.dst.neighbour)
2196 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2197
2198 if (rt->u.dst.dev)
2199 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2200
2201 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2202
2203 expires = rt->rt6i_expires ? rt->rt6i_expires - jiffies : 0;
2204 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
2205 expires, rt->u.dst.error) < 0)
2206 goto nla_put_failure;
2207
2208 return nlmsg_end(skb, nlh);
2209
2210 nla_put_failure:
2211 nlmsg_cancel(skb, nlh);
2212 return -EMSGSIZE;
2213 }
2214
2215 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2216 {
2217 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2218 int prefix;
2219
2220 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2221 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2222 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2223 } else
2224 prefix = 0;
2225
2226 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2227 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2228 prefix, 0, NLM_F_MULTI);
2229 }
2230
2231 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2232 {
2233 struct net *net = sock_net(in_skb->sk);
2234 struct nlattr *tb[RTA_MAX+1];
2235 struct rt6_info *rt;
2236 struct sk_buff *skb;
2237 struct rtmsg *rtm;
2238 struct flowi fl;
2239 int err, iif = 0;
2240
2241 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2242 if (err < 0)
2243 goto errout;
2244
2245 err = -EINVAL;
2246 memset(&fl, 0, sizeof(fl));
2247
2248 if (tb[RTA_SRC]) {
2249 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2250 goto errout;
2251
2252 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2253 }
2254
2255 if (tb[RTA_DST]) {
2256 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2257 goto errout;
2258
2259 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2260 }
2261
2262 if (tb[RTA_IIF])
2263 iif = nla_get_u32(tb[RTA_IIF]);
2264
2265 if (tb[RTA_OIF])
2266 fl.oif = nla_get_u32(tb[RTA_OIF]);
2267
2268 if (iif) {
2269 struct net_device *dev;
2270 dev = __dev_get_by_index(net, iif);
2271 if (!dev) {
2272 err = -ENODEV;
2273 goto errout;
2274 }
2275 }
2276
2277 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2278 if (skb == NULL) {
2279 err = -ENOBUFS;
2280 goto errout;
2281 }
2282
2283 /* Reserve room for dummy headers, this skb can pass
2284 through good chunk of routing engine.
2285 */
2286 skb_reset_mac_header(skb);
2287 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2288
2289 rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl);
2290 skb->dst = &rt->u.dst;
2291
2292 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2293 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2294 nlh->nlmsg_seq, 0, 0, 0);
2295 if (err < 0) {
2296 kfree_skb(skb);
2297 goto errout;
2298 }
2299
2300 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2301 errout:
2302 return err;
2303 }
2304
2305 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2306 {
2307 struct sk_buff *skb;
2308 struct net *net = info->nl_net;
2309 u32 seq;
2310 int err;
2311
2312 err = -ENOBUFS;
2313 seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0;
2314
2315 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2316 if (skb == NULL)
2317 goto errout;
2318
2319 err = rt6_fill_node(skb, rt, NULL, NULL, 0,
2320 event, info->pid, seq, 0, 0, 0);
2321 if (err < 0) {
2322 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2323 WARN_ON(err == -EMSGSIZE);
2324 kfree_skb(skb);
2325 goto errout;
2326 }
2327 err = rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE,
2328 info->nlh, gfp_any());
2329 errout:
2330 if (err < 0)
2331 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
2332 }
2333
2334 static int ip6_route_dev_notify(struct notifier_block *this,
2335 unsigned long event, void *data)
2336 {
2337 struct net_device *dev = (struct net_device *)data;
2338 struct net *net = dev_net(dev);
2339
2340 if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
2341 net->ipv6.ip6_null_entry->u.dst.dev = dev;
2342 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
2343 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2344 net->ipv6.ip6_prohibit_entry->u.dst.dev = dev;
2345 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
2346 net->ipv6.ip6_blk_hole_entry->u.dst.dev = dev;
2347 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
2348 #endif
2349 }
2350
2351 return NOTIFY_OK;
2352 }
2353
2354 /*
2355 * /proc
2356 */
2357
2358 #ifdef CONFIG_PROC_FS
2359
2360 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2361
2362 struct rt6_proc_arg
2363 {
2364 char *buffer;
2365 int offset;
2366 int length;
2367 int skip;
2368 int len;
2369 };
2370
2371 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2372 {
2373 struct seq_file *m = p_arg;
2374
2375 seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_dst.addr),
2376 rt->rt6i_dst.plen);
2377
2378 #ifdef CONFIG_IPV6_SUBTREES
2379 seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_src.addr),
2380 rt->rt6i_src.plen);
2381 #else
2382 seq_puts(m, "00000000000000000000000000000000 00 ");
2383 #endif
2384
2385 if (rt->rt6i_nexthop) {
2386 seq_printf(m, NIP6_SEQFMT,
2387 NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key)));
2388 } else {
2389 seq_puts(m, "00000000000000000000000000000000");
2390 }
2391 seq_printf(m, " %08x %08x %08x %08x %8s\n",
2392 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2393 rt->u.dst.__use, rt->rt6i_flags,
2394 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2395 return 0;
2396 }
2397
2398 static int ipv6_route_show(struct seq_file *m, void *v)
2399 {
2400 struct net *net = (struct net *)m->private;
2401 fib6_clean_all(net, rt6_info_route, 0, m);
2402 return 0;
2403 }
2404
2405 static int ipv6_route_open(struct inode *inode, struct file *file)
2406 {
2407 int err;
2408 struct net *net = get_proc_net(inode);
2409 if (!net)
2410 return -ENXIO;
2411
2412 err = single_open(file, ipv6_route_show, net);
2413 if (err < 0) {
2414 put_net(net);
2415 return err;
2416 }
2417
2418 return 0;
2419 }
2420
2421 static int ipv6_route_release(struct inode *inode, struct file *file)
2422 {
2423 struct seq_file *seq = file->private_data;
2424 struct net *net = seq->private;
2425 put_net(net);
2426 return single_release(inode, file);
2427 }
2428
2429 static const struct file_operations ipv6_route_proc_fops = {
2430 .owner = THIS_MODULE,
2431 .open = ipv6_route_open,
2432 .read = seq_read,
2433 .llseek = seq_lseek,
2434 .release = ipv6_route_release,
2435 };
2436
2437 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2438 {
2439 struct net *net = (struct net *)seq->private;
2440 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2441 net->ipv6.rt6_stats->fib_nodes,
2442 net->ipv6.rt6_stats->fib_route_nodes,
2443 net->ipv6.rt6_stats->fib_rt_alloc,
2444 net->ipv6.rt6_stats->fib_rt_entries,
2445 net->ipv6.rt6_stats->fib_rt_cache,
2446 atomic_read(&net->ipv6.ip6_dst_ops->entries),
2447 net->ipv6.rt6_stats->fib_discarded_routes);
2448
2449 return 0;
2450 }
2451
2452 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2453 {
2454 int err;
2455 struct net *net = get_proc_net(inode);
2456 if (!net)
2457 return -ENXIO;
2458
2459 err = single_open(file, rt6_stats_seq_show, net);
2460 if (err < 0) {
2461 put_net(net);
2462 return err;
2463 }
2464
2465 return 0;
2466 }
2467
2468 static int rt6_stats_seq_release(struct inode *inode, struct file *file)
2469 {
2470 struct seq_file *seq = file->private_data;
2471 struct net *net = (struct net *)seq->private;
2472 put_net(net);
2473 return single_release(inode, file);
2474 }
2475
2476 static const struct file_operations rt6_stats_seq_fops = {
2477 .owner = THIS_MODULE,
2478 .open = rt6_stats_seq_open,
2479 .read = seq_read,
2480 .llseek = seq_lseek,
2481 .release = rt6_stats_seq_release,
2482 };
2483 #endif /* CONFIG_PROC_FS */
2484
2485 #ifdef CONFIG_SYSCTL
2486
2487 static
2488 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2489 void __user *buffer, size_t *lenp, loff_t *ppos)
2490 {
2491 struct net *net = current->nsproxy->net_ns;
2492 int delay = net->ipv6.sysctl.flush_delay;
2493 if (write) {
2494 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2495 fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net);
2496 return 0;
2497 } else
2498 return -EINVAL;
2499 }
2500
2501 ctl_table ipv6_route_table_template[] = {
2502 {
2503 .procname = "flush",
2504 .data = &init_net.ipv6.sysctl.flush_delay,
2505 .maxlen = sizeof(int),
2506 .mode = 0200,
2507 .proc_handler = &ipv6_sysctl_rtcache_flush
2508 },
2509 {
2510 .ctl_name = NET_IPV6_ROUTE_GC_THRESH,
2511 .procname = "gc_thresh",
2512 .data = &ip6_dst_ops_template.gc_thresh,
2513 .maxlen = sizeof(int),
2514 .mode = 0644,
2515 .proc_handler = &proc_dointvec,
2516 },
2517 {
2518 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE,
2519 .procname = "max_size",
2520 .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
2521 .maxlen = sizeof(int),
2522 .mode = 0644,
2523 .proc_handler = &proc_dointvec,
2524 },
2525 {
2526 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2527 .procname = "gc_min_interval",
2528 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2529 .maxlen = sizeof(int),
2530 .mode = 0644,
2531 .proc_handler = &proc_dointvec_jiffies,
2532 .strategy = &sysctl_jiffies,
2533 },
2534 {
2535 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT,
2536 .procname = "gc_timeout",
2537 .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
2538 .maxlen = sizeof(int),
2539 .mode = 0644,
2540 .proc_handler = &proc_dointvec_jiffies,
2541 .strategy = &sysctl_jiffies,
2542 },
2543 {
2544 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL,
2545 .procname = "gc_interval",
2546 .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
2547 .maxlen = sizeof(int),
2548 .mode = 0644,
2549 .proc_handler = &proc_dointvec_jiffies,
2550 .strategy = &sysctl_jiffies,
2551 },
2552 {
2553 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY,
2554 .procname = "gc_elasticity",
2555 .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
2556 .maxlen = sizeof(int),
2557 .mode = 0644,
2558 .proc_handler = &proc_dointvec_jiffies,
2559 .strategy = &sysctl_jiffies,
2560 },
2561 {
2562 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES,
2563 .procname = "mtu_expires",
2564 .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
2565 .maxlen = sizeof(int),
2566 .mode = 0644,
2567 .proc_handler = &proc_dointvec_jiffies,
2568 .strategy = &sysctl_jiffies,
2569 },
2570 {
2571 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS,
2572 .procname = "min_adv_mss",
2573 .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
2574 .maxlen = sizeof(int),
2575 .mode = 0644,
2576 .proc_handler = &proc_dointvec_jiffies,
2577 .strategy = &sysctl_jiffies,
2578 },
2579 {
2580 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2581 .procname = "gc_min_interval_ms",
2582 .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
2583 .maxlen = sizeof(int),
2584 .mode = 0644,
2585 .proc_handler = &proc_dointvec_ms_jiffies,
2586 .strategy = &sysctl_ms_jiffies,
2587 },
2588 { .ctl_name = 0 }
2589 };
2590
2591 struct ctl_table *ipv6_route_sysctl_init(struct net *net)
2592 {
2593 struct ctl_table *table;
2594
2595 table = kmemdup(ipv6_route_table_template,
2596 sizeof(ipv6_route_table_template),
2597 GFP_KERNEL);
2598
2599 if (table) {
2600 table[0].data = &net->ipv6.sysctl.flush_delay;
2601 table[1].data = &net->ipv6.ip6_dst_ops->gc_thresh;
2602 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
2603 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
2604 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
2605 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
2606 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
2607 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
2608 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
2609 }
2610
2611 return table;
2612 }
2613 #endif
2614
2615 static int ip6_route_net_init(struct net *net)
2616 {
2617 int ret = -ENOMEM;
2618
2619 net->ipv6.ip6_dst_ops = kmemdup(&ip6_dst_ops_template,
2620 sizeof(*net->ipv6.ip6_dst_ops),
2621 GFP_KERNEL);
2622 if (!net->ipv6.ip6_dst_ops)
2623 goto out;
2624 net->ipv6.ip6_dst_ops->dst_net = hold_net(net);
2625
2626 net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
2627 sizeof(*net->ipv6.ip6_null_entry),
2628 GFP_KERNEL);
2629 if (!net->ipv6.ip6_null_entry)
2630 goto out_ip6_dst_ops;
2631 net->ipv6.ip6_null_entry->u.dst.path =
2632 (struct dst_entry *)net->ipv6.ip6_null_entry;
2633 net->ipv6.ip6_null_entry->u.dst.ops = net->ipv6.ip6_dst_ops;
2634
2635 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2636 net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
2637 sizeof(*net->ipv6.ip6_prohibit_entry),
2638 GFP_KERNEL);
2639 if (!net->ipv6.ip6_prohibit_entry) {
2640 kfree(net->ipv6.ip6_null_entry);
2641 goto out;
2642 }
2643 net->ipv6.ip6_prohibit_entry->u.dst.path =
2644 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
2645 net->ipv6.ip6_prohibit_entry->u.dst.ops = net->ipv6.ip6_dst_ops;
2646
2647 net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
2648 sizeof(*net->ipv6.ip6_blk_hole_entry),
2649 GFP_KERNEL);
2650 if (!net->ipv6.ip6_blk_hole_entry) {
2651 kfree(net->ipv6.ip6_null_entry);
2652 kfree(net->ipv6.ip6_prohibit_entry);
2653 goto out;
2654 }
2655 net->ipv6.ip6_blk_hole_entry->u.dst.path =
2656 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
2657 net->ipv6.ip6_blk_hole_entry->u.dst.ops = net->ipv6.ip6_dst_ops;
2658 #endif
2659
2660 #ifdef CONFIG_PROC_FS
2661 proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops);
2662 proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2663 #endif
2664 net->ipv6.ip6_rt_gc_expire = 30*HZ;
2665
2666 ret = 0;
2667 out:
2668 return ret;
2669
2670 out_ip6_dst_ops:
2671 release_net(net->ipv6.ip6_dst_ops->dst_net);
2672 kfree(net->ipv6.ip6_dst_ops);
2673 goto out;
2674 }
2675
2676 static void ip6_route_net_exit(struct net *net)
2677 {
2678 #ifdef CONFIG_PROC_FS
2679 proc_net_remove(net, "ipv6_route");
2680 proc_net_remove(net, "rt6_stats");
2681 #endif
2682 kfree(net->ipv6.ip6_null_entry);
2683 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2684 kfree(net->ipv6.ip6_prohibit_entry);
2685 kfree(net->ipv6.ip6_blk_hole_entry);
2686 #endif
2687 release_net(net->ipv6.ip6_dst_ops->dst_net);
2688 kfree(net->ipv6.ip6_dst_ops);
2689 }
2690
2691 static struct pernet_operations ip6_route_net_ops = {
2692 .init = ip6_route_net_init,
2693 .exit = ip6_route_net_exit,
2694 };
2695
2696 static struct notifier_block ip6_route_dev_notifier = {
2697 .notifier_call = ip6_route_dev_notify,
2698 .priority = 0,
2699 };
2700
2701 int __init ip6_route_init(void)
2702 {
2703 int ret;
2704
2705 ret = -ENOMEM;
2706 ip6_dst_ops_template.kmem_cachep =
2707 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2708 SLAB_HWCACHE_ALIGN, NULL);
2709 if (!ip6_dst_ops_template.kmem_cachep)
2710 goto out;;
2711
2712 ret = register_pernet_subsys(&ip6_route_net_ops);
2713 if (ret)
2714 goto out_kmem_cache;
2715
2716 /* Registering of the loopback is done before this portion of code,
2717 * the loopback reference in rt6_info will not be taken, do it
2718 * manually for init_net */
2719 init_net.ipv6.ip6_null_entry->u.dst.dev = init_net.loopback_dev;
2720 init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2721 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2722 init_net.ipv6.ip6_prohibit_entry->u.dst.dev = init_net.loopback_dev;
2723 init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2724 init_net.ipv6.ip6_blk_hole_entry->u.dst.dev = init_net.loopback_dev;
2725 init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
2726 #endif
2727 ret = fib6_init();
2728 if (ret)
2729 goto out_register_subsys;
2730
2731 ret = xfrm6_init();
2732 if (ret)
2733 goto out_fib6_init;
2734
2735 ret = fib6_rules_init();
2736 if (ret)
2737 goto xfrm6_init;
2738
2739 ret = -ENOBUFS;
2740 if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
2741 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
2742 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL))
2743 goto fib6_rules_init;
2744
2745 ret = register_netdevice_notifier(&ip6_route_dev_notifier);
2746 if (ret)
2747 goto fib6_rules_init;
2748
2749 out:
2750 return ret;
2751
2752 fib6_rules_init:
2753 fib6_rules_cleanup();
2754 xfrm6_init:
2755 xfrm6_fini();
2756 out_fib6_init:
2757 fib6_gc_cleanup();
2758 out_register_subsys:
2759 unregister_pernet_subsys(&ip6_route_net_ops);
2760 out_kmem_cache:
2761 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2762 goto out;
2763 }
2764
2765 void ip6_route_cleanup(void)
2766 {
2767 unregister_netdevice_notifier(&ip6_route_dev_notifier);
2768 fib6_rules_cleanup();
2769 xfrm6_fini();
2770 fib6_gc_cleanup();
2771 unregister_pernet_subsys(&ip6_route_net_ops);
2772 kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
2773 }