?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux/fpc-iii.git] / net / ipv6 / route.c
blobc953466b7afdbde3c77e6494c3f24a46908d9097
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/init.h>
40 #include <linux/if_arp.h>
41
42 #ifdef CONFIG_PROC_FS
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #endif
46
47 #include <net/snmp.h>
48 #include <net/ipv6.h>
49 #include <net/ip6_fib.h>
50 #include <net/ip6_route.h>
51 #include <net/ndisc.h>
52 #include <net/addrconf.h>
53 #include <net/tcp.h>
54 #include <linux/rtnetlink.h>
55 #include <net/dst.h>
56 #include <net/xfrm.h>
57 #include <net/netevent.h>
58 #include <net/netlink.h>
59
60 #include <asm/uaccess.h>
61
62 #ifdef CONFIG_SYSCTL
63 #include <linux/sysctl.h>
64 #endif
65
66 /* Set to 3 to get tracing. */
67 #define RT6_DEBUG 2
68
69 #if RT6_DEBUG >= 3
70 #define RDBG(x) printk x
71 #define RT6_TRACE(x...) printk(KERN_DEBUG x)
72 #else
73 #define RDBG(x)
74 #define RT6_TRACE(x...) do { ; } while (0)
75 #endif
76
77 #define CLONE_OFFLINK_ROUTE 0
78
79 static int ip6_rt_max_size = 4096;
80 static int ip6_rt_gc_min_interval = HZ / 2;
81 static int ip6_rt_gc_timeout = 60*HZ;
82 int ip6_rt_gc_interval = 30*HZ;
83 static int ip6_rt_gc_elasticity = 9;
84 static int ip6_rt_mtu_expires = 10*60*HZ;
85 static int ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
86
87 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
88 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
89 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
90 static void ip6_dst_destroy(struct dst_entry *);
91 static void ip6_dst_ifdown(struct dst_entry *,
92 struct net_device *dev, int how);
93 static int ip6_dst_gc(void);
94
95 static int ip6_pkt_discard(struct sk_buff *skb);
96 static int ip6_pkt_discard_out(struct sk_buff *skb);
97 static void ip6_link_failure(struct sk_buff *skb);
98 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
99
100 #ifdef CONFIG_IPV6_ROUTE_INFO
101 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
102 struct in6_addr *gwaddr, int ifindex,
103 unsigned pref);
104 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
105 struct in6_addr *gwaddr, int ifindex);
106 #endif
107
108 static struct dst_ops ip6_dst_ops = {
109 .family = AF_INET6,
110 .protocol = __constant_htons(ETH_P_IPV6),
111 .gc = ip6_dst_gc,
112 .gc_thresh = 1024,
113 .check = ip6_dst_check,
114 .destroy = ip6_dst_destroy,
115 .ifdown = ip6_dst_ifdown,
116 .negative_advice = ip6_negative_advice,
117 .link_failure = ip6_link_failure,
118 .update_pmtu = ip6_rt_update_pmtu,
119 .entry_size = sizeof(struct rt6_info),
120 };
121
122 struct rt6_info ip6_null_entry = {
123 .u = {
124 .dst = {
125 .__refcnt = ATOMIC_INIT(1),
126 .__use = 1,
127 .dev = &loopback_dev,
128 .obsolete = -1,
129 .error = -ENETUNREACH,
130 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
131 .input = ip6_pkt_discard,
132 .output = ip6_pkt_discard_out,
133 .ops = &ip6_dst_ops,
134 .path = (struct dst_entry*)&ip6_null_entry,
135 }
136 },
137 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
138 .rt6i_metric = ~(u32) 0,
139 .rt6i_ref = ATOMIC_INIT(1),
140 };
141
142 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
143
144 static int ip6_pkt_prohibit(struct sk_buff *skb);
145 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
146 static int ip6_pkt_blk_hole(struct sk_buff *skb);
147
148 struct rt6_info ip6_prohibit_entry = {
149 .u = {
150 .dst = {
151 .__refcnt = ATOMIC_INIT(1),
152 .__use = 1,
153 .dev = &loopback_dev,
154 .obsolete = -1,
155 .error = -EACCES,
156 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
157 .input = ip6_pkt_prohibit,
158 .output = ip6_pkt_prohibit_out,
159 .ops = &ip6_dst_ops,
160 .path = (struct dst_entry*)&ip6_prohibit_entry,
161 }
162 },
163 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
164 .rt6i_metric = ~(u32) 0,
165 .rt6i_ref = ATOMIC_INIT(1),
166 };
167
168 struct rt6_info ip6_blk_hole_entry = {
169 .u = {
170 .dst = {
171 .__refcnt = ATOMIC_INIT(1),
172 .__use = 1,
173 .dev = &loopback_dev,
174 .obsolete = -1,
175 .error = -EINVAL,
176 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
177 .input = ip6_pkt_blk_hole,
178 .output = ip6_pkt_blk_hole,
179 .ops = &ip6_dst_ops,
180 .path = (struct dst_entry*)&ip6_blk_hole_entry,
181 }
182 },
183 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
184 .rt6i_metric = ~(u32) 0,
185 .rt6i_ref = ATOMIC_INIT(1),
186 };
187
188 #endif
189
190 /* allocate dst with ip6_dst_ops */
191 static __inline__ struct rt6_info *ip6_dst_alloc(void)
192 {
193 return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
194 }
195
196 static void ip6_dst_destroy(struct dst_entry *dst)
197 {
198 struct rt6_info *rt = (struct rt6_info *)dst;
199 struct inet6_dev *idev = rt->rt6i_idev;
200
201 if (idev != NULL) {
202 rt->rt6i_idev = NULL;
203 in6_dev_put(idev);
204 }
205 }
206
207 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
208 int how)
209 {
210 struct rt6_info *rt = (struct rt6_info *)dst;
211 struct inet6_dev *idev = rt->rt6i_idev;
212
213 if (dev != &loopback_dev && idev != NULL && idev->dev == dev) {
214 struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev);
215 if (loopback_idev != NULL) {
216 rt->rt6i_idev = loopback_idev;
217 in6_dev_put(idev);
218 }
219 }
220 }
221
222 static __inline__ int rt6_check_expired(const struct rt6_info *rt)
223 {
224 return (rt->rt6i_flags & RTF_EXPIRES &&
225 time_after(jiffies, rt->rt6i_expires));
226 }
227
228 static inline int rt6_need_strict(struct in6_addr *daddr)
229 {
230 return (ipv6_addr_type(daddr) &
231 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
232 }
233
234 /*
235 * Route lookup. Any table->tb6_lock is implied.
236 */
237
238 static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
239 int oif,
240 int strict)
241 {
242 struct rt6_info *local = NULL;
243 struct rt6_info *sprt;
244
245 if (oif) {
246 for (sprt = rt; sprt; sprt = sprt->u.next) {
247 struct net_device *dev = sprt->rt6i_dev;
248 if (dev->ifindex == oif)
249 return sprt;
250 if (dev->flags & IFF_LOOPBACK) {
251 if (sprt->rt6i_idev == NULL ||
252 sprt->rt6i_idev->dev->ifindex != oif) {
253 if (strict && oif)
254 continue;
255 if (local && (!oif ||
256 local->rt6i_idev->dev->ifindex == oif))
257 continue;
258 }
259 local = sprt;
260 }
261 }
262
263 if (local)
264 return local;
265
266 if (strict)
267 return &ip6_null_entry;
268 }
269 return rt;
270 }
271
272 #ifdef CONFIG_IPV6_ROUTER_PREF
273 static void rt6_probe(struct rt6_info *rt)
274 {
275 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
276 /*
277 * Okay, this does not seem to be appropriate
278 * for now, however, we need to check if it
279 * is really so; aka Router Reachability Probing.
280 *
281 * Router Reachability Probe MUST be rate-limited
282 * to no more than one per minute.
283 */
284 if (!neigh || (neigh->nud_state & NUD_VALID))
285 return;
286 read_lock_bh(&neigh->lock);
287 if (!(neigh->nud_state & NUD_VALID) &&
288 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
289 struct in6_addr mcaddr;
290 struct in6_addr *target;
291
292 neigh->updated = jiffies;
293 read_unlock_bh(&neigh->lock);
294
295 target = (struct in6_addr *)&neigh->primary_key;
296 addrconf_addr_solict_mult(target, &mcaddr);
297 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
298 } else
299 read_unlock_bh(&neigh->lock);
300 }
301 #else
302 static inline void rt6_probe(struct rt6_info *rt)
303 {
304 return;
305 }
306 #endif
307
308 /*
309 * Default Router Selection (RFC 2461 6.3.6)
310 */
311 static int inline rt6_check_dev(struct rt6_info *rt, int oif)
312 {
313 struct net_device *dev = rt->rt6i_dev;
314 if (!oif || dev->ifindex == oif)
315 return 2;
316 if ((dev->flags & IFF_LOOPBACK) &&
317 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
318 return 1;
319 return 0;
320 }
321
322 static int inline rt6_check_neigh(struct rt6_info *rt)
323 {
324 struct neighbour *neigh = rt->rt6i_nexthop;
325 int m = 0;
326 if (rt->rt6i_flags & RTF_NONEXTHOP ||
327 !(rt->rt6i_flags & RTF_GATEWAY))
328 m = 1;
329 else if (neigh) {
330 read_lock_bh(&neigh->lock);
331 if (neigh->nud_state & NUD_VALID)
332 m = 2;
333 read_unlock_bh(&neigh->lock);
334 }
335 return m;
336 }
337
338 static int rt6_score_route(struct rt6_info *rt, int oif,
339 int strict)
340 {
341 int m, n;
342
343 m = rt6_check_dev(rt, oif);
344 if (!m && (strict & RT6_LOOKUP_F_IFACE))
345 return -1;
346 #ifdef CONFIG_IPV6_ROUTER_PREF
347 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
348 #endif
349 n = rt6_check_neigh(rt);
350 if (n > 1)
351 m |= 16;
352 else if (!n && strict & RT6_LOOKUP_F_REACHABLE)
353 return -1;
354 return m;
355 }
356
357 static struct rt6_info *rt6_select(struct rt6_info **head, int oif,
358 int strict)
359 {
360 struct rt6_info *match = NULL, *last = NULL;
361 struct rt6_info *rt, *rt0 = *head;
362 u32 metric;
363 int mpri = -1;
364
365 RT6_TRACE("%s(head=%p(*head=%p), oif=%d)\n",
366 __FUNCTION__, head, head ? *head : NULL, oif);
367
368 for (rt = rt0, metric = rt0->rt6i_metric;
369 rt && rt->rt6i_metric == metric && (!last || rt != rt0);
370 rt = rt->u.next) {
371 int m;
372
373 if (rt6_check_expired(rt))
374 continue;
375
376 last = rt;
377
378 m = rt6_score_route(rt, oif, strict);
379 if (m < 0)
380 continue;
381
382 if (m > mpri) {
383 rt6_probe(match);
384 match = rt;
385 mpri = m;
386 } else {
387 rt6_probe(rt);
388 }
389 }
390
391 if (!match &&
392 (strict & RT6_LOOKUP_F_REACHABLE) &&
393 last && last != rt0) {
394 /* no entries matched; do round-robin */
395 static DEFINE_SPINLOCK(lock);
396 spin_lock(&lock);
397 *head = rt0->u.next;
398 rt0->u.next = last->u.next;
399 last->u.next = rt0;
400 spin_unlock(&lock);
401 }
402
403 RT6_TRACE("%s() => %p, score=%d\n",
404 __FUNCTION__, match, mpri);
405
406 return (match ? match : &ip6_null_entry);
407 }
408
409 #ifdef CONFIG_IPV6_ROUTE_INFO
410 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
411 struct in6_addr *gwaddr)
412 {
413 struct route_info *rinfo = (struct route_info *) opt;
414 struct in6_addr prefix_buf, *prefix;
415 unsigned int pref;
416 u32 lifetime;
417 struct rt6_info *rt;
418
419 if (len < sizeof(struct route_info)) {
420 return -EINVAL;
421 }
422
423 /* Sanity check for prefix_len and length */
424 if (rinfo->length > 3) {
425 return -EINVAL;
426 } else if (rinfo->prefix_len > 128) {
427 return -EINVAL;
428 } else if (rinfo->prefix_len > 64) {
429 if (rinfo->length < 2) {
430 return -EINVAL;
431 }
432 } else if (rinfo->prefix_len > 0) {
433 if (rinfo->length < 1) {
434 return -EINVAL;
435 }
436 }
437
438 pref = rinfo->route_pref;
439 if (pref == ICMPV6_ROUTER_PREF_INVALID)
440 pref = ICMPV6_ROUTER_PREF_MEDIUM;
441
442 lifetime = htonl(rinfo->lifetime);
443 if (lifetime == 0xffffffff) {
444 /* infinity */
445 } else if (lifetime > 0x7fffffff/HZ) {
446 /* Avoid arithmetic overflow */
447 lifetime = 0x7fffffff/HZ - 1;
448 }
449
450 if (rinfo->length == 3)
451 prefix = (struct in6_addr *)rinfo->prefix;
452 else {
453 /* this function is safe */
454 ipv6_addr_prefix(&prefix_buf,
455 (struct in6_addr *)rinfo->prefix,
456 rinfo->prefix_len);
457 prefix = &prefix_buf;
458 }
459
460 rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
461
462 if (rt && !lifetime) {
463 ip6_del_rt(rt);
464 rt = NULL;
465 }
466
467 if (!rt && lifetime)
468 rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
469 pref);
470 else if (rt)
471 rt->rt6i_flags = RTF_ROUTEINFO |
472 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
473
474 if (rt) {
475 if (lifetime == 0xffffffff) {
476 rt->rt6i_flags &= ~RTF_EXPIRES;
477 } else {
478 rt->rt6i_expires = jiffies + HZ * lifetime;
479 rt->rt6i_flags |= RTF_EXPIRES;
480 }
481 dst_release(&rt->u.dst);
482 }
483 return 0;
484 }
485 #endif
486
487 #define BACKTRACK(saddr) \
488 do { \
489 if (rt == &ip6_null_entry) { \
490 struct fib6_node *pn; \
491 while (1) { \
492 if (fn->fn_flags & RTN_TL_ROOT) \
493 goto out; \
494 pn = fn->parent; \
495 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
496 fn = fib6_lookup(pn->subtree, NULL, saddr); \
497 else \
498 fn = pn; \
499 if (fn->fn_flags & RTN_RTINFO) \
500 goto restart; \
501 } \
502 } \
503 } while(0)
504
505 static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
506 struct flowi *fl, int flags)
507 {
508 struct fib6_node *fn;
509 struct rt6_info *rt;
510
511 read_lock_bh(&table->tb6_lock);
512 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
513 restart:
514 rt = fn->leaf;
515 rt = rt6_device_match(rt, fl->oif, flags);
516 BACKTRACK(&fl->fl6_src);
517 out:
518 dst_hold(&rt->u.dst);
519 read_unlock_bh(&table->tb6_lock);
520
521 rt->u.dst.lastuse = jiffies;
522 rt->u.dst.__use++;
523
524 return rt;
525
526 }
527
528 struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
529 int oif, int strict)
530 {
531 struct flowi fl = {
532 .oif = oif,
533 .nl_u = {
534 .ip6_u = {
535 .daddr = *daddr,
536 },
537 },
538 };
539 struct dst_entry *dst;
540 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
541
542 if (saddr) {
543 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
544 flags |= RT6_LOOKUP_F_HAS_SADDR;
545 }
546
547 dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
548 if (dst->error == 0)
549 return (struct rt6_info *) dst;
550
551 dst_release(dst);
552
553 return NULL;
554 }
555
556 /* ip6_ins_rt is called with FREE table->tb6_lock.
557 It takes new route entry, the addition fails by any reason the
558 route is freed. In any case, if caller does not hold it, it may
559 be destroyed.
560 */
561
562 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
563 {
564 int err;
565 struct fib6_table *table;
566
567 table = rt->rt6i_table;
568 write_lock_bh(&table->tb6_lock);
569 err = fib6_add(&table->tb6_root, rt, info);
570 write_unlock_bh(&table->tb6_lock);
571
572 return err;
573 }
574
575 int ip6_ins_rt(struct rt6_info *rt)
576 {
577 return __ip6_ins_rt(rt, NULL);
578 }
579
580 static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
581 struct in6_addr *saddr)
582 {
583 struct rt6_info *rt;
584
585 /*
586 * Clone the route.
587 */
588
589 rt = ip6_rt_copy(ort);
590
591 if (rt) {
592 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
593 if (rt->rt6i_dst.plen != 128 &&
594 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
595 rt->rt6i_flags |= RTF_ANYCAST;
596 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
597 }
598
599 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
600 rt->rt6i_dst.plen = 128;
601 rt->rt6i_flags |= RTF_CACHE;
602 rt->u.dst.flags |= DST_HOST;
603
604 #ifdef CONFIG_IPV6_SUBTREES
605 if (rt->rt6i_src.plen && saddr) {
606 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
607 rt->rt6i_src.plen = 128;
608 }
609 #endif
610
611 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
612
613 }
614
615 return rt;
616 }
617
618 static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
619 {
620 struct rt6_info *rt = ip6_rt_copy(ort);
621 if (rt) {
622 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
623 rt->rt6i_dst.plen = 128;
624 rt->rt6i_flags |= RTF_CACHE;
625 rt->u.dst.flags |= DST_HOST;
626 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
627 }
628 return rt;
629 }
630
631 static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
632 struct flowi *fl, int flags)
633 {
634 struct fib6_node *fn;
635 struct rt6_info *rt, *nrt;
636 int strict = 0;
637 int attempts = 3;
638 int err;
639 int reachable = RT6_LOOKUP_F_REACHABLE;
640
641 strict |= flags & RT6_LOOKUP_F_IFACE;
642
643 relookup:
644 read_lock_bh(&table->tb6_lock);
645
646 restart_2:
647 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
648
649 restart:
650 rt = rt6_select(&fn->leaf, fl->iif, strict | reachable);
651 BACKTRACK(&fl->fl6_src);
652 if (rt == &ip6_null_entry ||
653 rt->rt6i_flags & RTF_CACHE)
654 goto out;
655
656 dst_hold(&rt->u.dst);
657 read_unlock_bh(&table->tb6_lock);
658
659 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
660 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
661 else {
662 #if CLONE_OFFLINK_ROUTE
663 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
664 #else
665 goto out2;
666 #endif
667 }
668
669 dst_release(&rt->u.dst);
670 rt = nrt ? : &ip6_null_entry;
671
672 dst_hold(&rt->u.dst);
673 if (nrt) {
674 err = ip6_ins_rt(nrt);
675 if (!err)
676 goto out2;
677 }
678
679 if (--attempts <= 0)
680 goto out2;
681
682 /*
683 * Race condition! In the gap, when table->tb6_lock was
684 * released someone could insert this route. Relookup.
685 */
686 dst_release(&rt->u.dst);
687 goto relookup;
688
689 out:
690 if (reachable) {
691 reachable = 0;
692 goto restart_2;
693 }
694 dst_hold(&rt->u.dst);
695 read_unlock_bh(&table->tb6_lock);
696 out2:
697 rt->u.dst.lastuse = jiffies;
698 rt->u.dst.__use++;
699
700 return rt;
701 }
702
703 void ip6_route_input(struct sk_buff *skb)
704 {
705 struct ipv6hdr *iph = skb->nh.ipv6h;
706 int flags = RT6_LOOKUP_F_HAS_SADDR;
707 struct flowi fl = {
708 .iif = skb->dev->ifindex,
709 .nl_u = {
710 .ip6_u = {
711 .daddr = iph->daddr,
712 .saddr = iph->saddr,
713 #ifdef CONFIG_IPV6_ROUTE_FWMARK
714 .fwmark = skb->nfmark,
715 #endif
716 .flowlabel = (* (u32 *) iph)&IPV6_FLOWINFO_MASK,
717 },
718 },
719 .proto = iph->nexthdr,
720 };
721
722 if (rt6_need_strict(&iph->daddr))
723 flags |= RT6_LOOKUP_F_IFACE;
724
725 skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
726 }
727
728 static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
729 struct flowi *fl, int flags)
730 {
731 struct fib6_node *fn;
732 struct rt6_info *rt, *nrt;
733 int strict = 0;
734 int attempts = 3;
735 int err;
736 int reachable = RT6_LOOKUP_F_REACHABLE;
737
738 strict |= flags & RT6_LOOKUP_F_IFACE;
739
740 relookup:
741 read_lock_bh(&table->tb6_lock);
742
743 restart_2:
744 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
745
746 restart:
747 rt = rt6_select(&fn->leaf, fl->oif, strict | reachable);
748 BACKTRACK(&fl->fl6_src);
749 if (rt == &ip6_null_entry ||
750 rt->rt6i_flags & RTF_CACHE)
751 goto out;
752
753 dst_hold(&rt->u.dst);
754 read_unlock_bh(&table->tb6_lock);
755
756 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
757 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
758 else {
759 #if CLONE_OFFLINK_ROUTE
760 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
761 #else
762 goto out2;
763 #endif
764 }
765
766 dst_release(&rt->u.dst);
767 rt = nrt ? : &ip6_null_entry;
768
769 dst_hold(&rt->u.dst);
770 if (nrt) {
771 err = ip6_ins_rt(nrt);
772 if (!err)
773 goto out2;
774 }
775
776 if (--attempts <= 0)
777 goto out2;
778
779 /*
780 * Race condition! In the gap, when table->tb6_lock was
781 * released someone could insert this route. Relookup.
782 */
783 dst_release(&rt->u.dst);
784 goto relookup;
785
786 out:
787 if (reachable) {
788 reachable = 0;
789 goto restart_2;
790 }
791 dst_hold(&rt->u.dst);
792 read_unlock_bh(&table->tb6_lock);
793 out2:
794 rt->u.dst.lastuse = jiffies;
795 rt->u.dst.__use++;
796 return rt;
797 }
798
799 struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
800 {
801 int flags = 0;
802
803 if (rt6_need_strict(&fl->fl6_dst))
804 flags |= RT6_LOOKUP_F_IFACE;
805
806 if (!ipv6_addr_any(&fl->fl6_src))
807 flags |= RT6_LOOKUP_F_HAS_SADDR;
808
809 return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
810 }
811
812
813 /*
814 * Destination cache support functions
815 */
816
817 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
818 {
819 struct rt6_info *rt;
820
821 rt = (struct rt6_info *) dst;
822
823 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
824 return dst;
825
826 return NULL;
827 }
828
829 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
830 {
831 struct rt6_info *rt = (struct rt6_info *) dst;
832
833 if (rt) {
834 if (rt->rt6i_flags & RTF_CACHE)
835 ip6_del_rt(rt);
836 else
837 dst_release(dst);
838 }
839 return NULL;
840 }
841
842 static void ip6_link_failure(struct sk_buff *skb)
843 {
844 struct rt6_info *rt;
845
846 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
847
848 rt = (struct rt6_info *) skb->dst;
849 if (rt) {
850 if (rt->rt6i_flags&RTF_CACHE) {
851 dst_set_expires(&rt->u.dst, 0);
852 rt->rt6i_flags |= RTF_EXPIRES;
853 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
854 rt->rt6i_node->fn_sernum = -1;
855 }
856 }
857
858 static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
859 {
860 struct rt6_info *rt6 = (struct rt6_info*)dst;
861
862 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
863 rt6->rt6i_flags |= RTF_MODIFIED;
864 if (mtu < IPV6_MIN_MTU) {
865 mtu = IPV6_MIN_MTU;
866 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
867 }
868 dst->metrics[RTAX_MTU-1] = mtu;
869 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
870 }
871 }
872
873 static int ipv6_get_mtu(struct net_device *dev);
874
875 static inline unsigned int ipv6_advmss(unsigned int mtu)
876 {
877 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
878
879 if (mtu < ip6_rt_min_advmss)
880 mtu = ip6_rt_min_advmss;
881
882 /*
883 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
884 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
885 * IPV6_MAXPLEN is also valid and means: "any MSS,
886 * rely only on pmtu discovery"
887 */
888 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
889 mtu = IPV6_MAXPLEN;
890 return mtu;
891 }
892
893 static struct dst_entry *ndisc_dst_gc_list;
894 static DEFINE_SPINLOCK(ndisc_lock);
895
896 struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
897 struct neighbour *neigh,
898 struct in6_addr *addr,
899 int (*output)(struct sk_buff *))
900 {
901 struct rt6_info *rt;
902 struct inet6_dev *idev = in6_dev_get(dev);
903
904 if (unlikely(idev == NULL))
905 return NULL;
906
907 rt = ip6_dst_alloc();
908 if (unlikely(rt == NULL)) {
909 in6_dev_put(idev);
910 goto out;
911 }
912
913 dev_hold(dev);
914 if (neigh)
915 neigh_hold(neigh);
916 else
917 neigh = ndisc_get_neigh(dev, addr);
918
919 rt->rt6i_dev = dev;
920 rt->rt6i_idev = idev;
921 rt->rt6i_nexthop = neigh;
922 atomic_set(&rt->u.dst.__refcnt, 1);
923 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
924 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
925 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
926 rt->u.dst.output = output;
927
928 #if 0 /* there's no chance to use these for ndisc */
929 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
930 ? DST_HOST
931 : 0;
932 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
933 rt->rt6i_dst.plen = 128;
934 #endif
935
936 spin_lock_bh(&ndisc_lock);
937 rt->u.dst.next = ndisc_dst_gc_list;
938 ndisc_dst_gc_list = &rt->u.dst;
939 spin_unlock_bh(&ndisc_lock);
940
941 fib6_force_start_gc();
942
943 out:
944 return (struct dst_entry *)rt;
945 }
946
947 int ndisc_dst_gc(int *more)
948 {
949 struct dst_entry *dst, *next, **pprev;
950 int freed;
951
952 next = NULL;
953 freed = 0;
954
955 spin_lock_bh(&ndisc_lock);
956 pprev = &ndisc_dst_gc_list;
957
958 while ((dst = *pprev) != NULL) {
959 if (!atomic_read(&dst->__refcnt)) {
960 *pprev = dst->next;
961 dst_free(dst);
962 freed++;
963 } else {
964 pprev = &dst->next;
965 (*more)++;
966 }
967 }
968
969 spin_unlock_bh(&ndisc_lock);
970
971 return freed;
972 }
973
974 static int ip6_dst_gc(void)
975 {
976 static unsigned expire = 30*HZ;
977 static unsigned long last_gc;
978 unsigned long now = jiffies;
979
980 if (time_after(last_gc + ip6_rt_gc_min_interval, now) &&
981 atomic_read(&ip6_dst_ops.entries) <= ip6_rt_max_size)
982 goto out;
983
984 expire++;
985 fib6_run_gc(expire);
986 last_gc = now;
987 if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
988 expire = ip6_rt_gc_timeout>>1;
989
990 out:
991 expire -= expire>>ip6_rt_gc_elasticity;
992 return (atomic_read(&ip6_dst_ops.entries) > ip6_rt_max_size);
993 }
994
995 /* Clean host part of a prefix. Not necessary in radix tree,
996 but results in cleaner routing tables.
997
998 Remove it only when all the things will work!
999 */
1000
1001 static int ipv6_get_mtu(struct net_device *dev)
1002 {
1003 int mtu = IPV6_MIN_MTU;
1004 struct inet6_dev *idev;
1005
1006 idev = in6_dev_get(dev);
1007 if (idev) {
1008 mtu = idev->cnf.mtu6;
1009 in6_dev_put(idev);
1010 }
1011 return mtu;
1012 }
1013
1014 int ipv6_get_hoplimit(struct net_device *dev)
1015 {
1016 int hoplimit = ipv6_devconf.hop_limit;
1017 struct inet6_dev *idev;
1018
1019 idev = in6_dev_get(dev);
1020 if (idev) {
1021 hoplimit = idev->cnf.hop_limit;
1022 in6_dev_put(idev);
1023 }
1024 return hoplimit;
1025 }
1026
1027 /*
1028 *
1029 */
1030
1031 int ip6_route_add(struct fib6_config *cfg)
1032 {
1033 int err;
1034 struct rt6_info *rt = NULL;
1035 struct net_device *dev = NULL;
1036 struct inet6_dev *idev = NULL;
1037 struct fib6_table *table;
1038 int addr_type;
1039
1040 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1041 return -EINVAL;
1042 #ifndef CONFIG_IPV6_SUBTREES
1043 if (cfg->fc_src_len)
1044 return -EINVAL;
1045 #endif
1046 if (cfg->fc_ifindex) {
1047 err = -ENODEV;
1048 dev = dev_get_by_index(cfg->fc_ifindex);
1049 if (!dev)
1050 goto out;
1051 idev = in6_dev_get(dev);
1052 if (!idev)
1053 goto out;
1054 }
1055
1056 if (cfg->fc_metric == 0)
1057 cfg->fc_metric = IP6_RT_PRIO_USER;
1058
1059 table = fib6_new_table(cfg->fc_table);
1060 if (table == NULL) {
1061 err = -ENOBUFS;
1062 goto out;
1063 }
1064
1065 rt = ip6_dst_alloc();
1066
1067 if (rt == NULL) {
1068 err = -ENOMEM;
1069 goto out;
1070 }
1071
1072 rt->u.dst.obsolete = -1;
1073 rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1074
1075 if (cfg->fc_protocol == RTPROT_UNSPEC)
1076 cfg->fc_protocol = RTPROT_BOOT;
1077 rt->rt6i_protocol = cfg->fc_protocol;
1078
1079 addr_type = ipv6_addr_type(&cfg->fc_dst);
1080
1081 if (addr_type & IPV6_ADDR_MULTICAST)
1082 rt->u.dst.input = ip6_mc_input;
1083 else
1084 rt->u.dst.input = ip6_forward;
1085
1086 rt->u.dst.output = ip6_output;
1087
1088 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1089 rt->rt6i_dst.plen = cfg->fc_dst_len;
1090 if (rt->rt6i_dst.plen == 128)
1091 rt->u.dst.flags = DST_HOST;
1092
1093 #ifdef CONFIG_IPV6_SUBTREES
1094 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1095 rt->rt6i_src.plen = cfg->fc_src_len;
1096 #endif
1097
1098 rt->rt6i_metric = cfg->fc_metric;
1099
1100 /* We cannot add true routes via loopback here,
1101 they would result in kernel looping; promote them to reject routes
1102 */
1103 if ((cfg->fc_flags & RTF_REJECT) ||
1104 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1105 /* hold loopback dev/idev if we haven't done so. */
1106 if (dev != &loopback_dev) {
1107 if (dev) {
1108 dev_put(dev);
1109 in6_dev_put(idev);
1110 }
1111 dev = &loopback_dev;
1112 dev_hold(dev);
1113 idev = in6_dev_get(dev);
1114 if (!idev) {
1115 err = -ENODEV;
1116 goto out;
1117 }
1118 }
1119 rt->u.dst.output = ip6_pkt_discard_out;
1120 rt->u.dst.input = ip6_pkt_discard;
1121 rt->u.dst.error = -ENETUNREACH;
1122 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1123 goto install_route;
1124 }
1125
1126 if (cfg->fc_flags & RTF_GATEWAY) {
1127 struct in6_addr *gw_addr;
1128 int gwa_type;
1129
1130 gw_addr = &cfg->fc_gateway;
1131 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1132 gwa_type = ipv6_addr_type(gw_addr);
1133
1134 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1135 struct rt6_info *grt;
1136
1137 /* IPv6 strictly inhibits using not link-local
1138 addresses as nexthop address.
1139 Otherwise, router will not able to send redirects.
1140 It is very good, but in some (rare!) circumstances
1141 (SIT, PtP, NBMA NOARP links) it is handy to allow
1142 some exceptions. --ANK
1143 */
1144 err = -EINVAL;
1145 if (!(gwa_type&IPV6_ADDR_UNICAST))
1146 goto out;
1147
1148 grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
1149
1150 err = -EHOSTUNREACH;
1151 if (grt == NULL)
1152 goto out;
1153 if (dev) {
1154 if (dev != grt->rt6i_dev) {
1155 dst_release(&grt->u.dst);
1156 goto out;
1157 }
1158 } else {
1159 dev = grt->rt6i_dev;
1160 idev = grt->rt6i_idev;
1161 dev_hold(dev);
1162 in6_dev_hold(grt->rt6i_idev);
1163 }
1164 if (!(grt->rt6i_flags&RTF_GATEWAY))
1165 err = 0;
1166 dst_release(&grt->u.dst);
1167
1168 if (err)
1169 goto out;
1170 }
1171 err = -EINVAL;
1172 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1173 goto out;
1174 }
1175
1176 err = -ENODEV;
1177 if (dev == NULL)
1178 goto out;
1179
1180 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1181 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1182 if (IS_ERR(rt->rt6i_nexthop)) {
1183 err = PTR_ERR(rt->rt6i_nexthop);
1184 rt->rt6i_nexthop = NULL;
1185 goto out;
1186 }
1187 }
1188
1189 rt->rt6i_flags = cfg->fc_flags;
1190
1191 install_route:
1192 if (cfg->fc_mx) {
1193 struct nlattr *nla;
1194 int remaining;
1195
1196 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1197 int type = nla->nla_type;
1198
1199 if (type) {
1200 if (type > RTAX_MAX) {
1201 err = -EINVAL;
1202 goto out;
1203 }
1204
1205 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1206 }
1207 }
1208 }
1209
1210 if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
1211 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1212 if (!rt->u.dst.metrics[RTAX_MTU-1])
1213 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1214 if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
1215 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1216 rt->u.dst.dev = dev;
1217 rt->rt6i_idev = idev;
1218 rt->rt6i_table = table;
1219 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1220
1221 out:
1222 if (dev)
1223 dev_put(dev);
1224 if (idev)
1225 in6_dev_put(idev);
1226 if (rt)
1227 dst_free((struct dst_entry *) rt);
1228 return err;
1229 }
1230
1231 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1232 {
1233 int err;
1234 struct fib6_table *table;
1235
1236 if (rt == &ip6_null_entry)
1237 return -ENOENT;
1238
1239 table = rt->rt6i_table;
1240 write_lock_bh(&table->tb6_lock);
1241
1242 err = fib6_del(rt, info);
1243 dst_release(&rt->u.dst);
1244
1245 write_unlock_bh(&table->tb6_lock);
1246
1247 return err;
1248 }
1249
1250 int ip6_del_rt(struct rt6_info *rt)
1251 {
1252 return __ip6_del_rt(rt, NULL);
1253 }
1254
1255 static int ip6_route_del(struct fib6_config *cfg)
1256 {
1257 struct fib6_table *table;
1258 struct fib6_node *fn;
1259 struct rt6_info *rt;
1260 int err = -ESRCH;
1261
1262 table = fib6_get_table(cfg->fc_table);
1263 if (table == NULL)
1264 return err;
1265
1266 read_lock_bh(&table->tb6_lock);
1267
1268 fn = fib6_locate(&table->tb6_root,
1269 &cfg->fc_dst, cfg->fc_dst_len,
1270 &cfg->fc_src, cfg->fc_src_len);
1271
1272 if (fn) {
1273 for (rt = fn->leaf; rt; rt = rt->u.next) {
1274 if (cfg->fc_ifindex &&
1275 (rt->rt6i_dev == NULL ||
1276 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1277 continue;
1278 if (cfg->fc_flags & RTF_GATEWAY &&
1279 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1280 continue;
1281 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1282 continue;
1283 dst_hold(&rt->u.dst);
1284 read_unlock_bh(&table->tb6_lock);
1285
1286 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1287 }
1288 }
1289 read_unlock_bh(&table->tb6_lock);
1290
1291 return err;
1292 }
1293
1294 /*
1295 * Handle redirects
1296 */
1297 struct ip6rd_flowi {
1298 struct flowi fl;
1299 struct in6_addr gateway;
1300 };
1301
1302 static struct rt6_info *__ip6_route_redirect(struct fib6_table *table,
1303 struct flowi *fl,
1304 int flags)
1305 {
1306 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1307 struct rt6_info *rt;
1308 struct fib6_node *fn;
1309
1310 /*
1311 * Get the "current" route for this destination and
1312 * check if the redirect has come from approriate router.
1313 *
1314 * RFC 2461 specifies that redirects should only be
1315 * accepted if they come from the nexthop to the target.
1316 * Due to the way the routes are chosen, this notion
1317 * is a bit fuzzy and one might need to check all possible
1318 * routes.
1319 */
1320
1321 read_lock_bh(&table->tb6_lock);
1322 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1323 restart:
1324 for (rt = fn->leaf; rt; rt = rt->u.next) {
1325 /*
1326 * Current route is on-link; redirect is always invalid.
1327 *
1328 * Seems, previous statement is not true. It could
1329 * be node, which looks for us as on-link (f.e. proxy ndisc)
1330 * But then router serving it might decide, that we should
1331 * know truth 8)8) --ANK (980726).
1332 */
1333 if (rt6_check_expired(rt))
1334 continue;
1335 if (!(rt->rt6i_flags & RTF_GATEWAY))
1336 continue;
1337 if (fl->oif != rt->rt6i_dev->ifindex)
1338 continue;
1339 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1340 continue;
1341 break;
1342 }
1343
1344 if (!rt)
1345 rt = &ip6_null_entry;
1346 BACKTRACK(&fl->fl6_src);
1347 out:
1348 dst_hold(&rt->u.dst);
1349
1350 read_unlock_bh(&table->tb6_lock);
1351
1352 return rt;
1353 };
1354
1355 static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1356 struct in6_addr *src,
1357 struct in6_addr *gateway,
1358 struct net_device *dev)
1359 {
1360 int flags = RT6_LOOKUP_F_HAS_SADDR;
1361 struct ip6rd_flowi rdfl = {
1362 .fl = {
1363 .oif = dev->ifindex,
1364 .nl_u = {
1365 .ip6_u = {
1366 .daddr = *dest,
1367 .saddr = *src,
1368 },
1369 },
1370 },
1371 .gateway = *gateway,
1372 };
1373
1374 if (rt6_need_strict(dest))
1375 flags |= RT6_LOOKUP_F_IFACE;
1376
1377 return (struct rt6_info *)fib6_rule_lookup((struct flowi *)&rdfl, flags, __ip6_route_redirect);
1378 }
1379
1380 void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1381 struct in6_addr *saddr,
1382 struct neighbour *neigh, u8 *lladdr, int on_link)
1383 {
1384 struct rt6_info *rt, *nrt = NULL;
1385 struct netevent_redirect netevent;
1386
1387 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1388
1389 if (rt == &ip6_null_entry) {
1390 if (net_ratelimit())
1391 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1392 "for redirect target\n");
1393 goto out;
1394 }
1395
1396 /*
1397 * We have finally decided to accept it.
1398 */
1399
1400 neigh_update(neigh, lladdr, NUD_STALE,
1401 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1402 NEIGH_UPDATE_F_OVERRIDE|
1403 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1404 NEIGH_UPDATE_F_ISROUTER))
1405 );
1406
1407 /*
1408 * Redirect received -> path was valid.
1409 * Look, redirects are sent only in response to data packets,
1410 * so that this nexthop apparently is reachable. --ANK
1411 */
1412 dst_confirm(&rt->u.dst);
1413
1414 /* Duplicate redirect: silently ignore. */
1415 if (neigh == rt->u.dst.neighbour)
1416 goto out;
1417
1418 nrt = ip6_rt_copy(rt);
1419 if (nrt == NULL)
1420 goto out;
1421
1422 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1423 if (on_link)
1424 nrt->rt6i_flags &= ~RTF_GATEWAY;
1425
1426 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1427 nrt->rt6i_dst.plen = 128;
1428 nrt->u.dst.flags |= DST_HOST;
1429
1430 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1431 nrt->rt6i_nexthop = neigh_clone(neigh);
1432 /* Reset pmtu, it may be better */
1433 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1434 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));
1435
1436 if (ip6_ins_rt(nrt))
1437 goto out;
1438
1439 netevent.old = &rt->u.dst;
1440 netevent.new = &nrt->u.dst;
1441 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1442
1443 if (rt->rt6i_flags&RTF_CACHE) {
1444 ip6_del_rt(rt);
1445 return;
1446 }
1447
1448 out:
1449 dst_release(&rt->u.dst);
1450 return;
1451 }
1452
1453 /*
1454 * Handle ICMP "packet too big" messages
1455 * i.e. Path MTU discovery
1456 */
1457
1458 void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1459 struct net_device *dev, u32 pmtu)
1460 {
1461 struct rt6_info *rt, *nrt;
1462 int allfrag = 0;
1463
1464 rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
1465 if (rt == NULL)
1466 return;
1467
1468 if (pmtu >= dst_mtu(&rt->u.dst))
1469 goto out;
1470
1471 if (pmtu < IPV6_MIN_MTU) {
1472 /*
1473 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1474 * MTU (1280) and a fragment header should always be included
1475 * after a node receiving Too Big message reporting PMTU is
1476 * less than the IPv6 Minimum Link MTU.
1477 */
1478 pmtu = IPV6_MIN_MTU;
1479 allfrag = 1;
1480 }
1481
1482 /* New mtu received -> path was valid.
1483 They are sent only in response to data packets,
1484 so that this nexthop apparently is reachable. --ANK
1485 */
1486 dst_confirm(&rt->u.dst);
1487
1488 /* Host route. If it is static, it would be better
1489 not to override it, but add new one, so that
1490 when cache entry will expire old pmtu
1491 would return automatically.
1492 */
1493 if (rt->rt6i_flags & RTF_CACHE) {
1494 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1495 if (allfrag)
1496 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1497 dst_set_expires(&rt->u.dst, ip6_rt_mtu_expires);
1498 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1499 goto out;
1500 }
1501
1502 /* Network route.
1503 Two cases are possible:
1504 1. It is connected route. Action: COW
1505 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1506 */
1507 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1508 nrt = rt6_alloc_cow(rt, daddr, saddr);
1509 else
1510 nrt = rt6_alloc_clone(rt, daddr);
1511
1512 if (nrt) {
1513 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1514 if (allfrag)
1515 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1516
1517 /* According to RFC 1981, detecting PMTU increase shouldn't be
1518 * happened within 5 mins, the recommended timer is 10 mins.
1519 * Here this route expiration time is set to ip6_rt_mtu_expires
1520 * which is 10 mins. After 10 mins the decreased pmtu is expired
1521 * and detecting PMTU increase will be automatically happened.
1522 */
1523 dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires);
1524 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1525
1526 ip6_ins_rt(nrt);
1527 }
1528 out:
1529 dst_release(&rt->u.dst);
1530 }
1531
1532 /*
1533 * Misc support functions
1534 */
1535
1536 static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1537 {
1538 struct rt6_info *rt = ip6_dst_alloc();
1539
1540 if (rt) {
1541 rt->u.dst.input = ort->u.dst.input;
1542 rt->u.dst.output = ort->u.dst.output;
1543
1544 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1545 rt->u.dst.error = ort->u.dst.error;
1546 rt->u.dst.dev = ort->u.dst.dev;
1547 if (rt->u.dst.dev)
1548 dev_hold(rt->u.dst.dev);
1549 rt->rt6i_idev = ort->rt6i_idev;
1550 if (rt->rt6i_idev)
1551 in6_dev_hold(rt->rt6i_idev);
1552 rt->u.dst.lastuse = jiffies;
1553 rt->rt6i_expires = 0;
1554
1555 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1556 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1557 rt->rt6i_metric = 0;
1558
1559 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1560 #ifdef CONFIG_IPV6_SUBTREES
1561 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1562 #endif
1563 rt->rt6i_table = ort->rt6i_table;
1564 }
1565 return rt;
1566 }
1567
1568 #ifdef CONFIG_IPV6_ROUTE_INFO
1569 static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
1570 struct in6_addr *gwaddr, int ifindex)
1571 {
1572 struct fib6_node *fn;
1573 struct rt6_info *rt = NULL;
1574 struct fib6_table *table;
1575
1576 table = fib6_get_table(RT6_TABLE_INFO);
1577 if (table == NULL)
1578 return NULL;
1579
1580 write_lock_bh(&table->tb6_lock);
1581 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1582 if (!fn)
1583 goto out;
1584
1585 for (rt = fn->leaf; rt; rt = rt->u.next) {
1586 if (rt->rt6i_dev->ifindex != ifindex)
1587 continue;
1588 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1589 continue;
1590 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1591 continue;
1592 dst_hold(&rt->u.dst);
1593 break;
1594 }
1595 out:
1596 write_unlock_bh(&table->tb6_lock);
1597 return rt;
1598 }
1599
1600 static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
1601 struct in6_addr *gwaddr, int ifindex,
1602 unsigned pref)
1603 {
1604 struct fib6_config cfg = {
1605 .fc_table = RT6_TABLE_INFO,
1606 .fc_metric = 1024,
1607 .fc_ifindex = ifindex,
1608 .fc_dst_len = prefixlen,
1609 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1610 RTF_UP | RTF_PREF(pref),
1611 };
1612
1613 ipv6_addr_copy(&cfg.fc_dst, prefix);
1614 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1615
1616 /* We should treat it as a default route if prefix length is 0. */
1617 if (!prefixlen)
1618 cfg.fc_flags |= RTF_DEFAULT;
1619
1620 ip6_route_add(&cfg);
1621
1622 return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
1623 }
1624 #endif
1625
1626 struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1627 {
1628 struct rt6_info *rt;
1629 struct fib6_table *table;
1630
1631 table = fib6_get_table(RT6_TABLE_DFLT);
1632 if (table == NULL)
1633 return NULL;
1634
1635 write_lock_bh(&table->tb6_lock);
1636 for (rt = table->tb6_root.leaf; rt; rt=rt->u.next) {
1637 if (dev == rt->rt6i_dev &&
1638 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1639 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1640 break;
1641 }
1642 if (rt)
1643 dst_hold(&rt->u.dst);
1644 write_unlock_bh(&table->tb6_lock);
1645 return rt;
1646 }
1647
1648 struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1649 struct net_device *dev,
1650 unsigned int pref)
1651 {
1652 struct fib6_config cfg = {
1653 .fc_table = RT6_TABLE_DFLT,
1654 .fc_metric = 1024,
1655 .fc_ifindex = dev->ifindex,
1656 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1657 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1658 };
1659
1660 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1661
1662 ip6_route_add(&cfg);
1663
1664 return rt6_get_dflt_router(gwaddr, dev);
1665 }
1666
1667 void rt6_purge_dflt_routers(void)
1668 {
1669 struct rt6_info *rt;
1670 struct fib6_table *table;
1671
1672 /* NOTE: Keep consistent with rt6_get_dflt_router */
1673 table = fib6_get_table(RT6_TABLE_DFLT);
1674 if (table == NULL)
1675 return;
1676
1677 restart:
1678 read_lock_bh(&table->tb6_lock);
1679 for (rt = table->tb6_root.leaf; rt; rt = rt->u.next) {
1680 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1681 dst_hold(&rt->u.dst);
1682 read_unlock_bh(&table->tb6_lock);
1683 ip6_del_rt(rt);
1684 goto restart;
1685 }
1686 }
1687 read_unlock_bh(&table->tb6_lock);
1688 }
1689
1690 static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
1691 struct fib6_config *cfg)
1692 {
1693 memset(cfg, 0, sizeof(*cfg));
1694
1695 cfg->fc_table = RT6_TABLE_MAIN;
1696 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1697 cfg->fc_metric = rtmsg->rtmsg_metric;
1698 cfg->fc_expires = rtmsg->rtmsg_info;
1699 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1700 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1701 cfg->fc_flags = rtmsg->rtmsg_flags;
1702
1703 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1704 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1705 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1706 }
1707
1708 int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
1709 {
1710 struct fib6_config cfg;
1711 struct in6_rtmsg rtmsg;
1712 int err;
1713
1714 switch(cmd) {
1715 case SIOCADDRT: /* Add a route */
1716 case SIOCDELRT: /* Delete a route */
1717 if (!capable(CAP_NET_ADMIN))
1718 return -EPERM;
1719 err = copy_from_user(&rtmsg, arg,
1720 sizeof(struct in6_rtmsg));
1721 if (err)
1722 return -EFAULT;
1723
1724 rtmsg_to_fib6_config(&rtmsg, &cfg);
1725
1726 rtnl_lock();
1727 switch (cmd) {
1728 case SIOCADDRT:
1729 err = ip6_route_add(&cfg);
1730 break;
1731 case SIOCDELRT:
1732 err = ip6_route_del(&cfg);
1733 break;
1734 default:
1735 err = -EINVAL;
1736 }
1737 rtnl_unlock();
1738
1739 return err;
1740 };
1741
1742 return -EINVAL;
1743 }
1744
1745 /*
1746 * Drop the packet on the floor
1747 */
1748
1749 static inline int ip6_pkt_drop(struct sk_buff *skb, int code)
1750 {
1751 int type = ipv6_addr_type(&skb->nh.ipv6h->daddr);
1752 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED)
1753 IP6_INC_STATS(IPSTATS_MIB_INADDRERRORS);
1754
1755 IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
1756 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
1757 kfree_skb(skb);
1758 return 0;
1759 }
1760
1761 static int ip6_pkt_discard(struct sk_buff *skb)
1762 {
1763 return ip6_pkt_drop(skb, ICMPV6_NOROUTE);
1764 }
1765
1766 static int ip6_pkt_discard_out(struct sk_buff *skb)
1767 {
1768 skb->dev = skb->dst->dev;
1769 return ip6_pkt_discard(skb);
1770 }
1771
1772 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
1773
1774 static int ip6_pkt_prohibit(struct sk_buff *skb)
1775 {
1776 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED);
1777 }
1778
1779 static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1780 {
1781 skb->dev = skb->dst->dev;
1782 return ip6_pkt_prohibit(skb);
1783 }
1784
1785 static int ip6_pkt_blk_hole(struct sk_buff *skb)
1786 {
1787 kfree_skb(skb);
1788 return 0;
1789 }
1790
1791 #endif
1792
1793 /*
1794 * Allocate a dst for local (unicast / anycast) address.
1795 */
1796
1797 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1798 const struct in6_addr *addr,
1799 int anycast)
1800 {
1801 struct rt6_info *rt = ip6_dst_alloc();
1802
1803 if (rt == NULL)
1804 return ERR_PTR(-ENOMEM);
1805
1806 dev_hold(&loopback_dev);
1807 in6_dev_hold(idev);
1808
1809 rt->u.dst.flags = DST_HOST;
1810 rt->u.dst.input = ip6_input;
1811 rt->u.dst.output = ip6_output;
1812 rt->rt6i_dev = &loopback_dev;
1813 rt->rt6i_idev = idev;
1814 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1815 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1816 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1817 rt->u.dst.obsolete = -1;
1818
1819 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1820 if (anycast)
1821 rt->rt6i_flags |= RTF_ANYCAST;
1822 else
1823 rt->rt6i_flags |= RTF_LOCAL;
1824 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1825 if (rt->rt6i_nexthop == NULL) {
1826 dst_free((struct dst_entry *) rt);
1827 return ERR_PTR(-ENOMEM);
1828 }
1829
1830 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1831 rt->rt6i_dst.plen = 128;
1832 rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
1833
1834 atomic_set(&rt->u.dst.__refcnt, 1);
1835
1836 return rt;
1837 }
1838
1839 static int fib6_ifdown(struct rt6_info *rt, void *arg)
1840 {
1841 if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
1842 rt != &ip6_null_entry) {
1843 RT6_TRACE("deleted by ifdown %p\n", rt);
1844 return -1;
1845 }
1846 return 0;
1847 }
1848
1849 void rt6_ifdown(struct net_device *dev)
1850 {
1851 fib6_clean_all(fib6_ifdown, 0, dev);
1852 }
1853
1854 struct rt6_mtu_change_arg
1855 {
1856 struct net_device *dev;
1857 unsigned mtu;
1858 };
1859
1860 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1861 {
1862 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1863 struct inet6_dev *idev;
1864
1865 /* In IPv6 pmtu discovery is not optional,
1866 so that RTAX_MTU lock cannot disable it.
1867 We still use this lock to block changes
1868 caused by addrconf/ndisc.
1869 */
1870
1871 idev = __in6_dev_get(arg->dev);
1872 if (idev == NULL)
1873 return 0;
1874
1875 /* For administrative MTU increase, there is no way to discover
1876 IPv6 PMTU increase, so PMTU increase should be updated here.
1877 Since RFC 1981 doesn't include administrative MTU increase
1878 update PMTU increase is a MUST. (i.e. jumbo frame)
1879 */
1880 /*
1881 If new MTU is less than route PMTU, this new MTU will be the
1882 lowest MTU in the path, update the route PMTU to reflect PMTU
1883 decreases; if new MTU is greater than route PMTU, and the
1884 old MTU is the lowest MTU in the path, update the route PMTU
1885 to reflect the increase. In this case if the other nodes' MTU
1886 also have the lowest MTU, TOO BIG MESSAGE will be lead to
1887 PMTU discouvery.
1888 */
1889 if (rt->rt6i_dev == arg->dev &&
1890 !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1891 (dst_mtu(&rt->u.dst) > arg->mtu ||
1892 (dst_mtu(&rt->u.dst) < arg->mtu &&
1893 dst_mtu(&rt->u.dst) == idev->cnf.mtu6)))
1894 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1895 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu);
1896 return 0;
1897 }
1898
1899 void rt6_mtu_change(struct net_device *dev, unsigned mtu)
1900 {
1901 struct rt6_mtu_change_arg arg = {
1902 .dev = dev,
1903 .mtu = mtu,
1904 };
1905
1906 fib6_clean_all(rt6_mtu_change_route, 0, &arg);
1907 }
1908
1909 static struct nla_policy rtm_ipv6_policy[RTA_MAX+1] __read_mostly = {
1910 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
1911 [RTA_OIF] = { .type = NLA_U32 },
1912 [RTA_IIF] = { .type = NLA_U32 },
1913 [RTA_PRIORITY] = { .type = NLA_U32 },
1914 [RTA_METRICS] = { .type = NLA_NESTED },
1915 };
1916
1917 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
1918 struct fib6_config *cfg)
1919 {
1920 struct rtmsg *rtm;
1921 struct nlattr *tb[RTA_MAX+1];
1922 int err;
1923
1924 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
1925 if (err < 0)
1926 goto errout;
1927
1928 err = -EINVAL;
1929 rtm = nlmsg_data(nlh);
1930 memset(cfg, 0, sizeof(*cfg));
1931
1932 cfg->fc_table = rtm->rtm_table;
1933 cfg->fc_dst_len = rtm->rtm_dst_len;
1934 cfg->fc_src_len = rtm->rtm_src_len;
1935 cfg->fc_flags = RTF_UP;
1936 cfg->fc_protocol = rtm->rtm_protocol;
1937
1938 if (rtm->rtm_type == RTN_UNREACHABLE)
1939 cfg->fc_flags |= RTF_REJECT;
1940
1941 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
1942 cfg->fc_nlinfo.nlh = nlh;
1943
1944 if (tb[RTA_GATEWAY]) {
1945 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
1946 cfg->fc_flags |= RTF_GATEWAY;
1947 }
1948
1949 if (tb[RTA_DST]) {
1950 int plen = (rtm->rtm_dst_len + 7) >> 3;
1951
1952 if (nla_len(tb[RTA_DST]) < plen)
1953 goto errout;
1954
1955 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
1956 }
1957
1958 if (tb[RTA_SRC]) {
1959 int plen = (rtm->rtm_src_len + 7) >> 3;
1960
1961 if (nla_len(tb[RTA_SRC]) < plen)
1962 goto errout;
1963
1964 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
1965 }
1966
1967 if (tb[RTA_OIF])
1968 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
1969
1970 if (tb[RTA_PRIORITY])
1971 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
1972
1973 if (tb[RTA_METRICS]) {
1974 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
1975 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
1976 }
1977
1978 if (tb[RTA_TABLE])
1979 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
1980
1981 err = 0;
1982 errout:
1983 return err;
1984 }
1985
1986 int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
1987 {
1988 struct fib6_config cfg;
1989 int err;
1990
1991 err = rtm_to_fib6_config(skb, nlh, &cfg);
1992 if (err < 0)
1993 return err;
1994
1995 return ip6_route_del(&cfg);
1996 }
1997
1998 int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
1999 {
2000 struct fib6_config cfg;
2001 int err;
2002
2003 err = rtm_to_fib6_config(skb, nlh, &cfg);
2004 if (err < 0)
2005 return err;
2006
2007 return ip6_route_add(&cfg);
2008 }
2009
2010 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2011 struct in6_addr *dst, struct in6_addr *src,
2012 int iif, int type, u32 pid, u32 seq,
2013 int prefix, unsigned int flags)
2014 {
2015 struct rtmsg *rtm;
2016 struct nlmsghdr *nlh;
2017 struct rta_cacheinfo ci;
2018 u32 table;
2019
2020 if (prefix) { /* user wants prefix routes only */
2021 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2022 /* success since this is not a prefix route */
2023 return 1;
2024 }
2025 }
2026
2027 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2028 if (nlh == NULL)
2029 return -ENOBUFS;
2030
2031 rtm = nlmsg_data(nlh);
2032 rtm->rtm_family = AF_INET6;
2033 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2034 rtm->rtm_src_len = rt->rt6i_src.plen;
2035 rtm->rtm_tos = 0;
2036 if (rt->rt6i_table)
2037 table = rt->rt6i_table->tb6_id;
2038 else
2039 table = RT6_TABLE_UNSPEC;
2040 rtm->rtm_table = table;
2041 NLA_PUT_U32(skb, RTA_TABLE, table);
2042 if (rt->rt6i_flags&RTF_REJECT)
2043 rtm->rtm_type = RTN_UNREACHABLE;
2044 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2045 rtm->rtm_type = RTN_LOCAL;
2046 else
2047 rtm->rtm_type = RTN_UNICAST;
2048 rtm->rtm_flags = 0;
2049 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2050 rtm->rtm_protocol = rt->rt6i_protocol;
2051 if (rt->rt6i_flags&RTF_DYNAMIC)
2052 rtm->rtm_protocol = RTPROT_REDIRECT;
2053 else if (rt->rt6i_flags & RTF_ADDRCONF)
2054 rtm->rtm_protocol = RTPROT_KERNEL;
2055 else if (rt->rt6i_flags&RTF_DEFAULT)
2056 rtm->rtm_protocol = RTPROT_RA;
2057
2058 if (rt->rt6i_flags&RTF_CACHE)
2059 rtm->rtm_flags |= RTM_F_CLONED;
2060
2061 if (dst) {
2062 NLA_PUT(skb, RTA_DST, 16, dst);
2063 rtm->rtm_dst_len = 128;
2064 } else if (rtm->rtm_dst_len)
2065 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2066 #ifdef CONFIG_IPV6_SUBTREES
2067 if (src) {
2068 NLA_PUT(skb, RTA_SRC, 16, src);
2069 rtm->rtm_src_len = 128;
2070 } else if (rtm->rtm_src_len)
2071 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2072 #endif
2073 if (iif)
2074 NLA_PUT_U32(skb, RTA_IIF, iif);
2075 else if (dst) {
2076 struct in6_addr saddr_buf;
2077 if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2078 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2079 }
2080
2081 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2082 goto nla_put_failure;
2083
2084 if (rt->u.dst.neighbour)
2085 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2086
2087 if (rt->u.dst.dev)
2088 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2089
2090 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2091 ci.rta_lastuse = jiffies_to_clock_t(jiffies - rt->u.dst.lastuse);
2092 if (rt->rt6i_expires)
2093 ci.rta_expires = jiffies_to_clock_t(rt->rt6i_expires - jiffies);
2094 else
2095 ci.rta_expires = 0;
2096 ci.rta_used = rt->u.dst.__use;
2097 ci.rta_clntref = atomic_read(&rt->u.dst.__refcnt);
2098 ci.rta_error = rt->u.dst.error;
2099 ci.rta_id = 0;
2100 ci.rta_ts = 0;
2101 ci.rta_tsage = 0;
2102 NLA_PUT(skb, RTA_CACHEINFO, sizeof(ci), &ci);
2103
2104 return nlmsg_end(skb, nlh);
2105
2106 nla_put_failure:
2107 return nlmsg_cancel(skb, nlh);
2108 }
2109
2110 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2111 {
2112 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2113 int prefix;
2114
2115 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2116 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2117 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2118 } else
2119 prefix = 0;
2120
2121 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2122 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2123 prefix, NLM_F_MULTI);
2124 }
2125
2126 int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2127 {
2128 struct nlattr *tb[RTA_MAX+1];
2129 struct rt6_info *rt;
2130 struct sk_buff *skb;
2131 struct rtmsg *rtm;
2132 struct flowi fl;
2133 int err, iif = 0;
2134
2135 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2136 if (err < 0)
2137 goto errout;
2138
2139 err = -EINVAL;
2140 memset(&fl, 0, sizeof(fl));
2141
2142 if (tb[RTA_SRC]) {
2143 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2144 goto errout;
2145
2146 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2147 }
2148
2149 if (tb[RTA_DST]) {
2150 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2151 goto errout;
2152
2153 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2154 }
2155
2156 if (tb[RTA_IIF])
2157 iif = nla_get_u32(tb[RTA_IIF]);
2158
2159 if (tb[RTA_OIF])
2160 fl.oif = nla_get_u32(tb[RTA_OIF]);
2161
2162 if (iif) {
2163 struct net_device *dev;
2164 dev = __dev_get_by_index(iif);
2165 if (!dev) {
2166 err = -ENODEV;
2167 goto errout;
2168 }
2169 }
2170
2171 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2172 if (skb == NULL) {
2173 err = -ENOBUFS;
2174 goto errout;
2175 }
2176
2177 /* Reserve room for dummy headers, this skb can pass
2178 through good chunk of routing engine.
2179 */
2180 skb->mac.raw = skb->data;
2181 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2182
2183 rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
2184 skb->dst = &rt->u.dst;
2185
2186 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2187 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2188 nlh->nlmsg_seq, 0, 0);
2189 if (err < 0) {
2190 kfree_skb(skb);
2191 goto errout;
2192 }
2193
2194 err = rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
2195 errout:
2196 return err;
2197 }
2198
2199 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2200 {
2201 struct sk_buff *skb;
2202 u32 pid = 0, seq = 0;
2203 struct nlmsghdr *nlh = NULL;
2204 int payload = sizeof(struct rtmsg) + 256;
2205 int err = -ENOBUFS;
2206
2207 if (info) {
2208 pid = info->pid;
2209 nlh = info->nlh;
2210 if (nlh)
2211 seq = nlh->nlmsg_seq;
2212 }
2213
2214 skb = nlmsg_new(nlmsg_total_size(payload), gfp_any());
2215 if (skb == NULL)
2216 goto errout;
2217
2218 err = rt6_fill_node(skb, rt, NULL, NULL, 0, event, pid, seq, 0, 0);
2219 if (err < 0) {
2220 kfree_skb(skb);
2221 goto errout;
2222 }
2223
2224 err = rtnl_notify(skb, pid, RTNLGRP_IPV6_ROUTE, nlh, gfp_any());
2225 errout:
2226 if (err < 0)
2227 rtnl_set_sk_err(RTNLGRP_IPV6_ROUTE, err);
2228 }
2229
2230 /*
2231 * /proc
2232 */
2233
2234 #ifdef CONFIG_PROC_FS
2235
2236 #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2237
2238 struct rt6_proc_arg
2239 {
2240 char *buffer;
2241 int offset;
2242 int length;
2243 int skip;
2244 int len;
2245 };
2246
2247 static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2248 {
2249 struct rt6_proc_arg *arg = (struct rt6_proc_arg *) p_arg;
2250 int i;
2251
2252 if (arg->skip < arg->offset / RT6_INFO_LEN) {
2253 arg->skip++;
2254 return 0;
2255 }
2256
2257 if (arg->len >= arg->length)
2258 return 0;
2259
2260 for (i=0; i<16; i++) {
2261 sprintf(arg->buffer + arg->len, "%02x",
2262 rt->rt6i_dst.addr.s6_addr[i]);
2263 arg->len += 2;
2264 }
2265 arg->len += sprintf(arg->buffer + arg->len, " %02x ",
2266 rt->rt6i_dst.plen);
2267
2268 #ifdef CONFIG_IPV6_SUBTREES
2269 for (i=0; i<16; i++) {
2270 sprintf(arg->buffer + arg->len, "%02x",
2271 rt->rt6i_src.addr.s6_addr[i]);
2272 arg->len += 2;
2273 }
2274 arg->len += sprintf(arg->buffer + arg->len, " %02x ",
2275 rt->rt6i_src.plen);
2276 #else
2277 sprintf(arg->buffer + arg->len,
2278 "00000000000000000000000000000000 00 ");
2279 arg->len += 36;
2280 #endif
2281
2282 if (rt->rt6i_nexthop) {
2283 for (i=0; i<16; i++) {
2284 sprintf(arg->buffer + arg->len, "%02x",
2285 rt->rt6i_nexthop->primary_key[i]);
2286 arg->len += 2;
2287 }
2288 } else {
2289 sprintf(arg->buffer + arg->len,
2290 "00000000000000000000000000000000");
2291 arg->len += 32;
2292 }
2293 arg->len += sprintf(arg->buffer + arg->len,
2294 " %08x %08x %08x %08x %8s\n",
2295 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2296 rt->u.dst.__use, rt->rt6i_flags,
2297 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2298 return 0;
2299 }
2300
2301 static int rt6_proc_info(char *buffer, char **start, off_t offset, int length)
2302 {
2303 struct rt6_proc_arg arg = {
2304 .buffer = buffer,
2305 .offset = offset,
2306 .length = length,
2307 };
2308
2309 fib6_clean_all(rt6_info_route, 0, &arg);
2310
2311 *start = buffer;
2312 if (offset)
2313 *start += offset % RT6_INFO_LEN;
2314
2315 arg.len -= offset % RT6_INFO_LEN;
2316
2317 if (arg.len > length)
2318 arg.len = length;
2319 if (arg.len < 0)
2320 arg.len = 0;
2321
2322 return arg.len;
2323 }
2324
2325 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2326 {
2327 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2328 rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
2329 rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
2330 rt6_stats.fib_rt_cache,
2331 atomic_read(&ip6_dst_ops.entries),
2332 rt6_stats.fib_discarded_routes);
2333
2334 return 0;
2335 }
2336
2337 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2338 {
2339 return single_open(file, rt6_stats_seq_show, NULL);
2340 }
2341
2342 static struct file_operations rt6_stats_seq_fops = {
2343 .owner = THIS_MODULE,
2344 .open = rt6_stats_seq_open,
2345 .read = seq_read,
2346 .llseek = seq_lseek,
2347 .release = single_release,
2348 };
2349 #endif /* CONFIG_PROC_FS */
2350
2351 #ifdef CONFIG_SYSCTL
2352
2353 static int flush_delay;
2354
2355 static
2356 int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2357 void __user *buffer, size_t *lenp, loff_t *ppos)
2358 {
2359 if (write) {
2360 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2361 fib6_run_gc(flush_delay <= 0 ? ~0UL : (unsigned long)flush_delay);
2362 return 0;
2363 } else
2364 return -EINVAL;
2365 }
2366
2367 ctl_table ipv6_route_table[] = {
2368 {
2369 .ctl_name = NET_IPV6_ROUTE_FLUSH,
2370 .procname = "flush",
2371 .data = &flush_delay,
2372 .maxlen = sizeof(int),
2373 .mode = 0200,
2374 .proc_handler = &ipv6_sysctl_rtcache_flush
2375 },
2376 {
2377 .ctl_name = NET_IPV6_ROUTE_GC_THRESH,
2378 .procname = "gc_thresh",
2379 .data = &ip6_dst_ops.gc_thresh,
2380 .maxlen = sizeof(int),
2381 .mode = 0644,
2382 .proc_handler = &proc_dointvec,
2383 },
2384 {
2385 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE,
2386 .procname = "max_size",
2387 .data = &ip6_rt_max_size,
2388 .maxlen = sizeof(int),
2389 .mode = 0644,
2390 .proc_handler = &proc_dointvec,
2391 },
2392 {
2393 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2394 .procname = "gc_min_interval",
2395 .data = &ip6_rt_gc_min_interval,
2396 .maxlen = sizeof(int),
2397 .mode = 0644,
2398 .proc_handler = &proc_dointvec_jiffies,
2399 .strategy = &sysctl_jiffies,
2400 },
2401 {
2402 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT,
2403 .procname = "gc_timeout",
2404 .data = &ip6_rt_gc_timeout,
2405 .maxlen = sizeof(int),
2406 .mode = 0644,
2407 .proc_handler = &proc_dointvec_jiffies,
2408 .strategy = &sysctl_jiffies,
2409 },
2410 {
2411 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL,
2412 .procname = "gc_interval",
2413 .data = &ip6_rt_gc_interval,
2414 .maxlen = sizeof(int),
2415 .mode = 0644,
2416 .proc_handler = &proc_dointvec_jiffies,
2417 .strategy = &sysctl_jiffies,
2418 },
2419 {
2420 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY,
2421 .procname = "gc_elasticity",
2422 .data = &ip6_rt_gc_elasticity,
2423 .maxlen = sizeof(int),
2424 .mode = 0644,
2425 .proc_handler = &proc_dointvec_jiffies,
2426 .strategy = &sysctl_jiffies,
2427 },
2428 {
2429 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES,
2430 .procname = "mtu_expires",
2431 .data = &ip6_rt_mtu_expires,
2432 .maxlen = sizeof(int),
2433 .mode = 0644,
2434 .proc_handler = &proc_dointvec_jiffies,
2435 .strategy = &sysctl_jiffies,
2436 },
2437 {
2438 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS,
2439 .procname = "min_adv_mss",
2440 .data = &ip6_rt_min_advmss,
2441 .maxlen = sizeof(int),
2442 .mode = 0644,
2443 .proc_handler = &proc_dointvec_jiffies,
2444 .strategy = &sysctl_jiffies,
2445 },
2446 {
2447 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2448 .procname = "gc_min_interval_ms",
2449 .data = &ip6_rt_gc_min_interval,
2450 .maxlen = sizeof(int),
2451 .mode = 0644,
2452 .proc_handler = &proc_dointvec_ms_jiffies,
2453 .strategy = &sysctl_ms_jiffies,
2454 },
2455 { .ctl_name = 0 }
2456 };
2457
2458 #endif
2459
2460 void __init ip6_route_init(void)
2461 {
2462 struct proc_dir_entry *p;
2463
2464 ip6_dst_ops.kmem_cachep =
2465 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2466 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
2467 fib6_init();
2468 #ifdef CONFIG_PROC_FS
2469 p = proc_net_create("ipv6_route", 0, rt6_proc_info);
2470 if (p)
2471 p->owner = THIS_MODULE;
2472
2473 proc_net_fops_create("rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2474 #endif
2475 #ifdef CONFIG_XFRM
2476 xfrm6_init();
2477 #endif
2478 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2479 fib6_rules_init();
2480 #endif
2481 }
2482
2483 void ip6_route_cleanup(void)
2484 {
2485 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
2486 fib6_rules_cleanup();
2487 #endif
2488 #ifdef CONFIG_PROC_FS
2489 proc_net_remove("ipv6_route");
2490 proc_net_remove("rt6_stats");
2491 #endif
2492 #ifdef CONFIG_XFRM
2493 xfrm6_fini();
2494 #endif
2495 rt6_ifdown(NULL);
2496 fib6_gc_cleanup();
2497 kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
2498 }
Linux with added FPC-III support