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[TCP]: Make snd_cwnd_cnt 32-bit
[net-next-2.6.git] / net / ipv6 / route.c
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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/net_namespace.h>
48#include <net/snmp.h>
49#include <net/ipv6.h>
50#include <net/ip6_fib.h>
51#include <net/ip6_route.h>
52#include <net/ndisc.h>
53#include <net/addrconf.h>
54#include <net/tcp.h>
55#include <linux/rtnetlink.h>
56#include <net/dst.h>
57#include <net/xfrm.h>
58#include <net/netevent.h>
59#include <net/netlink.h>
60
61#include <asm/uaccess.h>
62
63#ifdef CONFIG_SYSCTL
64#include <linux/sysctl.h>
65#endif
66
67/* Set to 3 to get tracing. */
68#define RT6_DEBUG 2
69
70#if RT6_DEBUG >= 3
71#define RDBG(x) printk x
72#define RT6_TRACE(x...) printk(KERN_DEBUG x)
73#else
74#define RDBG(x)
75#define RT6_TRACE(x...) do { ; } while (0)
76#endif
77
78#define CLONE_OFFLINK_ROUTE 0
79
80static int ip6_rt_max_size = 4096;
81static int ip6_rt_gc_min_interval = HZ / 2;
82static int ip6_rt_gc_timeout = 60*HZ;
83int ip6_rt_gc_interval = 30*HZ;
84static int ip6_rt_gc_elasticity = 9;
85static int ip6_rt_mtu_expires = 10*60*HZ;
86static int ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
87
88static struct rt6_info * ip6_rt_copy(struct rt6_info *ort);
89static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
90static struct dst_entry *ip6_negative_advice(struct dst_entry *);
91static void ip6_dst_destroy(struct dst_entry *);
92static void ip6_dst_ifdown(struct dst_entry *,
93 struct net_device *dev, int how);
94static int ip6_dst_gc(void);
95
96static int ip6_pkt_discard(struct sk_buff *skb);
97static int ip6_pkt_discard_out(struct sk_buff *skb);
98static void ip6_link_failure(struct sk_buff *skb);
99static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
100
101#ifdef CONFIG_IPV6_ROUTE_INFO
102static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
103 struct in6_addr *gwaddr, int ifindex,
104 unsigned pref);
105static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
106 struct in6_addr *gwaddr, int ifindex);
107#endif
108
109static struct dst_ops ip6_dst_ops = {
110 .family = AF_INET6,
111 .protocol = __constant_htons(ETH_P_IPV6),
112 .gc = ip6_dst_gc,
113 .gc_thresh = 1024,
114 .check = ip6_dst_check,
115 .destroy = ip6_dst_destroy,
116 .ifdown = ip6_dst_ifdown,
117 .negative_advice = ip6_negative_advice,
118 .link_failure = ip6_link_failure,
119 .update_pmtu = ip6_rt_update_pmtu,
120 .entry_size = sizeof(struct rt6_info),
121};
122
123static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
124{
125}
126
127static struct dst_ops ip6_dst_blackhole_ops = {
128 .family = AF_INET6,
129 .protocol = __constant_htons(ETH_P_IPV6),
130 .destroy = ip6_dst_destroy,
131 .check = ip6_dst_check,
132 .update_pmtu = ip6_rt_blackhole_update_pmtu,
133 .entry_size = sizeof(struct rt6_info),
134};
135
136struct rt6_info ip6_null_entry = {
137 .u = {
138 .dst = {
139 .__refcnt = ATOMIC_INIT(1),
140 .__use = 1,
141 .obsolete = -1,
142 .error = -ENETUNREACH,
143 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
144 .input = ip6_pkt_discard,
145 .output = ip6_pkt_discard_out,
146 .ops = &ip6_dst_ops,
147 .path = (struct dst_entry*)&ip6_null_entry,
148 }
149 },
150 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
151 .rt6i_metric = ~(u32) 0,
152 .rt6i_ref = ATOMIC_INIT(1),
153};
154
155#ifdef CONFIG_IPV6_MULTIPLE_TABLES
156
157static int ip6_pkt_prohibit(struct sk_buff *skb);
158static int ip6_pkt_prohibit_out(struct sk_buff *skb);
159static int ip6_pkt_blk_hole(struct sk_buff *skb);
160
161struct rt6_info ip6_prohibit_entry = {
162 .u = {
163 .dst = {
164 .__refcnt = ATOMIC_INIT(1),
165 .__use = 1,
166 .obsolete = -1,
167 .error = -EACCES,
168 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
169 .input = ip6_pkt_prohibit,
170 .output = ip6_pkt_prohibit_out,
171 .ops = &ip6_dst_ops,
172 .path = (struct dst_entry*)&ip6_prohibit_entry,
173 }
174 },
175 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
176 .rt6i_metric = ~(u32) 0,
177 .rt6i_ref = ATOMIC_INIT(1),
178};
179
180struct rt6_info ip6_blk_hole_entry = {
181 .u = {
182 .dst = {
183 .__refcnt = ATOMIC_INIT(1),
184 .__use = 1,
185 .obsolete = -1,
186 .error = -EINVAL,
187 .metrics = { [RTAX_HOPLIMIT - 1] = 255, },
188 .input = ip6_pkt_blk_hole,
189 .output = ip6_pkt_blk_hole,
190 .ops = &ip6_dst_ops,
191 .path = (struct dst_entry*)&ip6_blk_hole_entry,
192 }
193 },
194 .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
195 .rt6i_metric = ~(u32) 0,
196 .rt6i_ref = ATOMIC_INIT(1),
197};
198
199#endif
200
201/* allocate dst with ip6_dst_ops */
202static __inline__ struct rt6_info *ip6_dst_alloc(void)
203{
204 return (struct rt6_info *)dst_alloc(&ip6_dst_ops);
205}
206
207static void ip6_dst_destroy(struct dst_entry *dst)
208{
209 struct rt6_info *rt = (struct rt6_info *)dst;
210 struct inet6_dev *idev = rt->rt6i_idev;
211
212 if (idev != NULL) {
213 rt->rt6i_idev = NULL;
214 in6_dev_put(idev);
215 }
216}
217
218static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
219 int how)
220{
221 struct rt6_info *rt = (struct rt6_info *)dst;
222 struct inet6_dev *idev = rt->rt6i_idev;
223
224 if (dev != init_net.loopback_dev && idev != NULL && idev->dev == dev) {
225 struct inet6_dev *loopback_idev = in6_dev_get(init_net.loopback_dev);
226 if (loopback_idev != NULL) {
227 rt->rt6i_idev = loopback_idev;
228 in6_dev_put(idev);
229 }
230 }
231}
232
233static __inline__ int rt6_check_expired(const struct rt6_info *rt)
234{
235 return (rt->rt6i_flags & RTF_EXPIRES &&
236 time_after(jiffies, rt->rt6i_expires));
237}
238
239static inline int rt6_need_strict(struct in6_addr *daddr)
240{
241 return (ipv6_addr_type(daddr) &
242 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
243}
244
245/*
246 * Route lookup. Any table->tb6_lock is implied.
247 */
248
249static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt,
250 int oif,
251 int strict)
252{
253 struct rt6_info *local = NULL;
254 struct rt6_info *sprt;
255
256 if (oif) {
257 for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) {
258 struct net_device *dev = sprt->rt6i_dev;
259 if (dev->ifindex == oif)
260 return sprt;
261 if (dev->flags & IFF_LOOPBACK) {
262 if (sprt->rt6i_idev == NULL ||
263 sprt->rt6i_idev->dev->ifindex != oif) {
264 if (strict && oif)
265 continue;
266 if (local && (!oif ||
267 local->rt6i_idev->dev->ifindex == oif))
268 continue;
269 }
270 local = sprt;
271 }
272 }
273
274 if (local)
275 return local;
276
277 if (strict)
278 return &ip6_null_entry;
279 }
280 return rt;
281}
282
283#ifdef CONFIG_IPV6_ROUTER_PREF
284static void rt6_probe(struct rt6_info *rt)
285{
286 struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL;
287 /*
288 * Okay, this does not seem to be appropriate
289 * for now, however, we need to check if it
290 * is really so; aka Router Reachability Probing.
291 *
292 * Router Reachability Probe MUST be rate-limited
293 * to no more than one per minute.
294 */
295 if (!neigh || (neigh->nud_state & NUD_VALID))
296 return;
297 read_lock_bh(&neigh->lock);
298 if (!(neigh->nud_state & NUD_VALID) &&
299 time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) {
300 struct in6_addr mcaddr;
301 struct in6_addr *target;
302
303 neigh->updated = jiffies;
304 read_unlock_bh(&neigh->lock);
305
306 target = (struct in6_addr *)&neigh->primary_key;
307 addrconf_addr_solict_mult(target, &mcaddr);
308 ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL);
309 } else
310 read_unlock_bh(&neigh->lock);
311}
312#else
313static inline void rt6_probe(struct rt6_info *rt)
314{
315 return;
316}
317#endif
318
319/*
320 * Default Router Selection (RFC 2461 6.3.6)
321 */
322static inline int rt6_check_dev(struct rt6_info *rt, int oif)
323{
324 struct net_device *dev = rt->rt6i_dev;
325 if (!oif || dev->ifindex == oif)
326 return 2;
327 if ((dev->flags & IFF_LOOPBACK) &&
328 rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
329 return 1;
330 return 0;
331}
332
333static inline int rt6_check_neigh(struct rt6_info *rt)
334{
335 struct neighbour *neigh = rt->rt6i_nexthop;
336 int m = 0;
337 if (rt->rt6i_flags & RTF_NONEXTHOP ||
338 !(rt->rt6i_flags & RTF_GATEWAY))
339 m = 1;
340 else if (neigh) {
341 read_lock_bh(&neigh->lock);
342 if (neigh->nud_state & NUD_VALID)
343 m = 2;
344 else if (!(neigh->nud_state & NUD_FAILED))
345 m = 1;
346 read_unlock_bh(&neigh->lock);
347 }
348 return m;
349}
350
351static int rt6_score_route(struct rt6_info *rt, int oif,
352 int strict)
353{
354 int m, n;
355
356 m = rt6_check_dev(rt, oif);
357 if (!m && (strict & RT6_LOOKUP_F_IFACE))
358 return -1;
359#ifdef CONFIG_IPV6_ROUTER_PREF
360 m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
361#endif
362 n = rt6_check_neigh(rt);
363 if (!n && (strict & RT6_LOOKUP_F_REACHABLE))
364 return -1;
365 return m;
366}
367
368static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
369 int *mpri, struct rt6_info *match)
370{
371 int m;
372
373 if (rt6_check_expired(rt))
374 goto out;
375
376 m = rt6_score_route(rt, oif, strict);
377 if (m < 0)
378 goto out;
379
380 if (m > *mpri) {
381 if (strict & RT6_LOOKUP_F_REACHABLE)
382 rt6_probe(match);
383 *mpri = m;
384 match = rt;
385 } else if (strict & RT6_LOOKUP_F_REACHABLE) {
386 rt6_probe(rt);
387 }
388
389out:
390 return match;
391}
392
393static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
394 struct rt6_info *rr_head,
395 u32 metric, int oif, int strict)
396{
397 struct rt6_info *rt, *match;
398 int mpri = -1;
399
400 match = NULL;
401 for (rt = rr_head; rt && rt->rt6i_metric == metric;
402 rt = rt->u.dst.rt6_next)
403 match = find_match(rt, oif, strict, &mpri, match);
404 for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric;
405 rt = rt->u.dst.rt6_next)
406 match = find_match(rt, oif, strict, &mpri, match);
407
408 return match;
409}
410
411static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
412{
413 struct rt6_info *match, *rt0;
414
415 RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n",
416 __FUNCTION__, fn->leaf, oif);
417
418 rt0 = fn->rr_ptr;
419 if (!rt0)
420 fn->rr_ptr = rt0 = fn->leaf;
421
422 match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict);
423
424 if (!match &&
425 (strict & RT6_LOOKUP_F_REACHABLE)) {
426 struct rt6_info *next = rt0->u.dst.rt6_next;
427
428 /* no entries matched; do round-robin */
429 if (!next || next->rt6i_metric != rt0->rt6i_metric)
430 next = fn->leaf;
431
432 if (next != rt0)
433 fn->rr_ptr = next;
434 }
435
436 RT6_TRACE("%s() => %p\n",
437 __FUNCTION__, match);
438
439 return (match ? match : &ip6_null_entry);
440}
441
442#ifdef CONFIG_IPV6_ROUTE_INFO
443int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
444 struct in6_addr *gwaddr)
445{
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(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
494
495 if (rt && !lifetime) {
496 ip6_del_rt(rt);
497 rt = NULL;
498 }
499
500 if (!rt && lifetime)
501 rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
502 pref);
503 else if (rt)
504 rt->rt6i_flags = RTF_ROUTEINFO |
505 (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
506
507 if (rt) {
508 if (lifetime == 0xffffffff) {
509 rt->rt6i_flags &= ~RTF_EXPIRES;
510 } else {
511 rt->rt6i_expires = jiffies + HZ * lifetime;
512 rt->rt6i_flags |= RTF_EXPIRES;
513 }
514 dst_release(&rt->u.dst);
515 }
516 return 0;
517}
518#endif
519
520#define BACKTRACK(saddr) \
521do { \
522 if (rt == &ip6_null_entry) { \
523 struct fib6_node *pn; \
524 while (1) { \
525 if (fn->fn_flags & RTN_TL_ROOT) \
526 goto out; \
527 pn = fn->parent; \
528 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \
529 fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \
530 else \
531 fn = pn; \
532 if (fn->fn_flags & RTN_RTINFO) \
533 goto restart; \
534 } \
535 } \
536} while(0)
537
538static struct rt6_info *ip6_pol_route_lookup(struct fib6_table *table,
539 struct flowi *fl, int flags)
540{
541 struct fib6_node *fn;
542 struct rt6_info *rt;
543
544 read_lock_bh(&table->tb6_lock);
545 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
546restart:
547 rt = fn->leaf;
548 rt = rt6_device_match(rt, fl->oif, flags);
549 BACKTRACK(&fl->fl6_src);
550out:
551 dst_hold(&rt->u.dst);
552 read_unlock_bh(&table->tb6_lock);
553
554 rt->u.dst.lastuse = jiffies;
555 rt->u.dst.__use++;
556
557 return rt;
558
559}
560
561struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
562 int oif, int strict)
563{
564 struct flowi fl = {
565 .oif = oif,
566 .nl_u = {
567 .ip6_u = {
568 .daddr = *daddr,
569 },
570 },
571 };
572 struct dst_entry *dst;
573 int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
574
575 if (saddr) {
576 memcpy(&fl.fl6_src, saddr, sizeof(*saddr));
577 flags |= RT6_LOOKUP_F_HAS_SADDR;
578 }
579
580 dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_lookup);
581 if (dst->error == 0)
582 return (struct rt6_info *) dst;
583
584 dst_release(dst);
585
586 return NULL;
587}
588
589EXPORT_SYMBOL(rt6_lookup);
590
591/* ip6_ins_rt is called with FREE table->tb6_lock.
592 It takes new route entry, the addition fails by any reason the
593 route is freed. In any case, if caller does not hold it, it may
594 be destroyed.
595 */
596
597static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info)
598{
599 int err;
600 struct fib6_table *table;
601
602 table = rt->rt6i_table;
603 write_lock_bh(&table->tb6_lock);
604 err = fib6_add(&table->tb6_root, rt, info);
605 write_unlock_bh(&table->tb6_lock);
606
607 return err;
608}
609
610int ip6_ins_rt(struct rt6_info *rt)
611{
612 return __ip6_ins_rt(rt, NULL);
613}
614
615static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr,
616 struct in6_addr *saddr)
617{
618 struct rt6_info *rt;
619
620 /*
621 * Clone the route.
622 */
623
624 rt = ip6_rt_copy(ort);
625
626 if (rt) {
627 if (!(rt->rt6i_flags&RTF_GATEWAY)) {
628 if (rt->rt6i_dst.plen != 128 &&
629 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr))
630 rt->rt6i_flags |= RTF_ANYCAST;
631 ipv6_addr_copy(&rt->rt6i_gateway, daddr);
632 }
633
634 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
635 rt->rt6i_dst.plen = 128;
636 rt->rt6i_flags |= RTF_CACHE;
637 rt->u.dst.flags |= DST_HOST;
638
639#ifdef CONFIG_IPV6_SUBTREES
640 if (rt->rt6i_src.plen && saddr) {
641 ipv6_addr_copy(&rt->rt6i_src.addr, saddr);
642 rt->rt6i_src.plen = 128;
643 }
644#endif
645
646 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
647
648 }
649
650 return rt;
651}
652
653static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr)
654{
655 struct rt6_info *rt = ip6_rt_copy(ort);
656 if (rt) {
657 ipv6_addr_copy(&rt->rt6i_dst.addr, daddr);
658 rt->rt6i_dst.plen = 128;
659 rt->rt6i_flags |= RTF_CACHE;
660 rt->u.dst.flags |= DST_HOST;
661 rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop);
662 }
663 return rt;
664}
665
666static struct rt6_info *ip6_pol_route_input(struct fib6_table *table,
667 struct flowi *fl, int flags)
668{
669 struct fib6_node *fn;
670 struct rt6_info *rt, *nrt;
671 int strict = 0;
672 int attempts = 3;
673 int err;
674 int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
675
676 strict |= flags & RT6_LOOKUP_F_IFACE;
677
678relookup:
679 read_lock_bh(&table->tb6_lock);
680
681restart_2:
682 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
683
684restart:
685 rt = rt6_select(fn, fl->iif, strict | reachable);
686 BACKTRACK(&fl->fl6_src);
687 if (rt == &ip6_null_entry ||
688 rt->rt6i_flags & RTF_CACHE)
689 goto out;
690
691 dst_hold(&rt->u.dst);
692 read_unlock_bh(&table->tb6_lock);
693
694 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
695 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
696 else {
697#if CLONE_OFFLINK_ROUTE
698 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
699#else
700 goto out2;
701#endif
702 }
703
704 dst_release(&rt->u.dst);
705 rt = nrt ? : &ip6_null_entry;
706
707 dst_hold(&rt->u.dst);
708 if (nrt) {
709 err = ip6_ins_rt(nrt);
710 if (!err)
711 goto out2;
712 }
713
714 if (--attempts <= 0)
715 goto out2;
716
717 /*
718 * Race condition! In the gap, when table->tb6_lock was
719 * released someone could insert this route. Relookup.
720 */
721 dst_release(&rt->u.dst);
722 goto relookup;
723
724out:
725 if (reachable) {
726 reachable = 0;
727 goto restart_2;
728 }
729 dst_hold(&rt->u.dst);
730 read_unlock_bh(&table->tb6_lock);
731out2:
732 rt->u.dst.lastuse = jiffies;
733 rt->u.dst.__use++;
734
735 return rt;
736}
737
738void ip6_route_input(struct sk_buff *skb)
739{
740 struct ipv6hdr *iph = ipv6_hdr(skb);
741 int flags = RT6_LOOKUP_F_HAS_SADDR;
742 struct flowi fl = {
743 .iif = skb->dev->ifindex,
744 .nl_u = {
745 .ip6_u = {
746 .daddr = iph->daddr,
747 .saddr = iph->saddr,
748 .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK,
749 },
750 },
751 .mark = skb->mark,
752 .proto = iph->nexthdr,
753 };
754
755 if (rt6_need_strict(&iph->daddr))
756 flags |= RT6_LOOKUP_F_IFACE;
757
758 skb->dst = fib6_rule_lookup(&fl, flags, ip6_pol_route_input);
759}
760
761static struct rt6_info *ip6_pol_route_output(struct fib6_table *table,
762 struct flowi *fl, int flags)
763{
764 struct fib6_node *fn;
765 struct rt6_info *rt, *nrt;
766 int strict = 0;
767 int attempts = 3;
768 int err;
769 int reachable = ipv6_devconf.forwarding ? 0 : RT6_LOOKUP_F_REACHABLE;
770
771 strict |= flags & RT6_LOOKUP_F_IFACE;
772
773relookup:
774 read_lock_bh(&table->tb6_lock);
775
776restart_2:
777 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
778
779restart:
780 rt = rt6_select(fn, fl->oif, strict | reachable);
781 BACKTRACK(&fl->fl6_src);
782 if (rt == &ip6_null_entry ||
783 rt->rt6i_flags & RTF_CACHE)
784 goto out;
785
786 dst_hold(&rt->u.dst);
787 read_unlock_bh(&table->tb6_lock);
788
789 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
790 nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src);
791 else {
792#if CLONE_OFFLINK_ROUTE
793 nrt = rt6_alloc_clone(rt, &fl->fl6_dst);
794#else
795 goto out2;
796#endif
797 }
798
799 dst_release(&rt->u.dst);
800 rt = nrt ? : &ip6_null_entry;
801
802 dst_hold(&rt->u.dst);
803 if (nrt) {
804 err = ip6_ins_rt(nrt);
805 if (!err)
806 goto out2;
807 }
808
809 if (--attempts <= 0)
810 goto out2;
811
812 /*
813 * Race condition! In the gap, when table->tb6_lock was
814 * released someone could insert this route. Relookup.
815 */
816 dst_release(&rt->u.dst);
817 goto relookup;
818
819out:
820 if (reachable) {
821 reachable = 0;
822 goto restart_2;
823 }
824 dst_hold(&rt->u.dst);
825 read_unlock_bh(&table->tb6_lock);
826out2:
827 rt->u.dst.lastuse = jiffies;
828 rt->u.dst.__use++;
829 return rt;
830}
831
832struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl)
833{
834 int flags = 0;
835
836 if (rt6_need_strict(&fl->fl6_dst))
837 flags |= RT6_LOOKUP_F_IFACE;
838
839 if (!ipv6_addr_any(&fl->fl6_src))
840 flags |= RT6_LOOKUP_F_HAS_SADDR;
841
842 return fib6_rule_lookup(fl, flags, ip6_pol_route_output);
843}
844
845EXPORT_SYMBOL(ip6_route_output);
846
847static int ip6_blackhole_output(struct sk_buff *skb)
848{
849 kfree_skb(skb);
850 return 0;
851}
852
853int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl)
854{
855 struct rt6_info *ort = (struct rt6_info *) *dstp;
856 struct rt6_info *rt = (struct rt6_info *)
857 dst_alloc(&ip6_dst_blackhole_ops);
858 struct dst_entry *new = NULL;
859
860 if (rt) {
861 new = &rt->u.dst;
862
863 atomic_set(&new->__refcnt, 1);
864 new->__use = 1;
865 new->input = ip6_blackhole_output;
866 new->output = ip6_blackhole_output;
867
868 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
869 new->dev = ort->u.dst.dev;
870 if (new->dev)
871 dev_hold(new->dev);
872 rt->rt6i_idev = ort->rt6i_idev;
873 if (rt->rt6i_idev)
874 in6_dev_hold(rt->rt6i_idev);
875 rt->rt6i_expires = 0;
876
877 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
878 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
879 rt->rt6i_metric = 0;
880
881 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
882#ifdef CONFIG_IPV6_SUBTREES
883 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
884#endif
885
886 dst_free(new);
887 }
888
889 dst_release(*dstp);
890 *dstp = new;
891 return (new ? 0 : -ENOMEM);
892}
893EXPORT_SYMBOL_GPL(ip6_dst_blackhole);
894
895/*
896 * Destination cache support functions
897 */
898
899static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
900{
901 struct rt6_info *rt;
902
903 rt = (struct rt6_info *) dst;
904
905 if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie))
906 return dst;
907
908 return NULL;
909}
910
911static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
912{
913 struct rt6_info *rt = (struct rt6_info *) dst;
914
915 if (rt) {
916 if (rt->rt6i_flags & RTF_CACHE)
917 ip6_del_rt(rt);
918 else
919 dst_release(dst);
920 }
921 return NULL;
922}
923
924static void ip6_link_failure(struct sk_buff *skb)
925{
926 struct rt6_info *rt;
927
928 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev);
929
930 rt = (struct rt6_info *) skb->dst;
931 if (rt) {
932 if (rt->rt6i_flags&RTF_CACHE) {
933 dst_set_expires(&rt->u.dst, 0);
934 rt->rt6i_flags |= RTF_EXPIRES;
935 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT))
936 rt->rt6i_node->fn_sernum = -1;
937 }
938}
939
940static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
941{
942 struct rt6_info *rt6 = (struct rt6_info*)dst;
943
944 if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) {
945 rt6->rt6i_flags |= RTF_MODIFIED;
946 if (mtu < IPV6_MIN_MTU) {
947 mtu = IPV6_MIN_MTU;
948 dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
949 }
950 dst->metrics[RTAX_MTU-1] = mtu;
951 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
952 }
953}
954
955static int ipv6_get_mtu(struct net_device *dev);
956
957static inline unsigned int ipv6_advmss(unsigned int mtu)
958{
959 mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
960
961 if (mtu < ip6_rt_min_advmss)
962 mtu = ip6_rt_min_advmss;
963
964 /*
965 * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
966 * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
967 * IPV6_MAXPLEN is also valid and means: "any MSS,
968 * rely only on pmtu discovery"
969 */
970 if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
971 mtu = IPV6_MAXPLEN;
972 return mtu;
973}
974
975static struct dst_entry *ndisc_dst_gc_list;
976static DEFINE_SPINLOCK(ndisc_lock);
977
978struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
979 struct neighbour *neigh,
980 struct in6_addr *addr,
981 int (*output)(struct sk_buff *))
982{
983 struct rt6_info *rt;
984 struct inet6_dev *idev = in6_dev_get(dev);
985
986 if (unlikely(idev == NULL))
987 return NULL;
988
989 rt = ip6_dst_alloc();
990 if (unlikely(rt == NULL)) {
991 in6_dev_put(idev);
992 goto out;
993 }
994
995 dev_hold(dev);
996 if (neigh)
997 neigh_hold(neigh);
998 else
999 neigh = ndisc_get_neigh(dev, addr);
1000
1001 rt->rt6i_dev = dev;
1002 rt->rt6i_idev = idev;
1003 rt->rt6i_nexthop = neigh;
1004 atomic_set(&rt->u.dst.__refcnt, 1);
1005 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255;
1006 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1007 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1008 rt->u.dst.output = output;
1009
1010#if 0 /* there's no chance to use these for ndisc */
1011 rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST
1012 ? DST_HOST
1013 : 0;
1014 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1015 rt->rt6i_dst.plen = 128;
1016#endif
1017
1018 spin_lock_bh(&ndisc_lock);
1019 rt->u.dst.next = ndisc_dst_gc_list;
1020 ndisc_dst_gc_list = &rt->u.dst;
1021 spin_unlock_bh(&ndisc_lock);
1022
1023 fib6_force_start_gc();
1024
1025out:
1026 return &rt->u.dst;
1027}
1028
1029int ndisc_dst_gc(int *more)
1030{
1031 struct dst_entry *dst, *next, **pprev;
1032 int freed;
1033
1034 next = NULL;
1035 freed = 0;
1036
1037 spin_lock_bh(&ndisc_lock);
1038 pprev = &ndisc_dst_gc_list;
1039
1040 while ((dst = *pprev) != NULL) {
1041 if (!atomic_read(&dst->__refcnt)) {
1042 *pprev = dst->next;
1043 dst_free(dst);
1044 freed++;
1045 } else {
1046 pprev = &dst->next;
1047 (*more)++;
1048 }
1049 }
1050
1051 spin_unlock_bh(&ndisc_lock);
1052
1053 return freed;
1054}
1055
1056static int ip6_dst_gc(void)
1057{
1058 static unsigned expire = 30*HZ;
1059 static unsigned long last_gc;
1060 unsigned long now = jiffies;
1061
1062 if (time_after(last_gc + ip6_rt_gc_min_interval, now) &&
1063 atomic_read(&ip6_dst_ops.entries) <= ip6_rt_max_size)
1064 goto out;
1065
1066 expire++;
1067 fib6_run_gc(expire);
1068 last_gc = now;
1069 if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh)
1070 expire = ip6_rt_gc_timeout>>1;
1071
1072out:
1073 expire -= expire>>ip6_rt_gc_elasticity;
1074 return (atomic_read(&ip6_dst_ops.entries) > ip6_rt_max_size);
1075}
1076
1077/* Clean host part of a prefix. Not necessary in radix tree,
1078 but results in cleaner routing tables.
1079
1080 Remove it only when all the things will work!
1081 */
1082
1083static int ipv6_get_mtu(struct net_device *dev)
1084{
1085 int mtu = IPV6_MIN_MTU;
1086 struct inet6_dev *idev;
1087
1088 idev = in6_dev_get(dev);
1089 if (idev) {
1090 mtu = idev->cnf.mtu6;
1091 in6_dev_put(idev);
1092 }
1093 return mtu;
1094}
1095
1096int ipv6_get_hoplimit(struct net_device *dev)
1097{
1098 int hoplimit = ipv6_devconf.hop_limit;
1099 struct inet6_dev *idev;
1100
1101 idev = in6_dev_get(dev);
1102 if (idev) {
1103 hoplimit = idev->cnf.hop_limit;
1104 in6_dev_put(idev);
1105 }
1106 return hoplimit;
1107}
1108
1109/*
1110 *
1111 */
1112
1113int ip6_route_add(struct fib6_config *cfg)
1114{
1115 int err;
1116 struct rt6_info *rt = NULL;
1117 struct net_device *dev = NULL;
1118 struct inet6_dev *idev = NULL;
1119 struct fib6_table *table;
1120 int addr_type;
1121
1122 if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1123 return -EINVAL;
1124#ifndef CONFIG_IPV6_SUBTREES
1125 if (cfg->fc_src_len)
1126 return -EINVAL;
1127#endif
1128 if (cfg->fc_ifindex) {
1129 err = -ENODEV;
1130 dev = dev_get_by_index(&init_net, cfg->fc_ifindex);
1131 if (!dev)
1132 goto out;
1133 idev = in6_dev_get(dev);
1134 if (!idev)
1135 goto out;
1136 }
1137
1138 if (cfg->fc_metric == 0)
1139 cfg->fc_metric = IP6_RT_PRIO_USER;
1140
1141 table = fib6_new_table(cfg->fc_table);
1142 if (table == NULL) {
1143 err = -ENOBUFS;
1144 goto out;
1145 }
1146
1147 rt = ip6_dst_alloc();
1148
1149 if (rt == NULL) {
1150 err = -ENOMEM;
1151 goto out;
1152 }
1153
1154 rt->u.dst.obsolete = -1;
1155 rt->rt6i_expires = jiffies + clock_t_to_jiffies(cfg->fc_expires);
1156
1157 if (cfg->fc_protocol == RTPROT_UNSPEC)
1158 cfg->fc_protocol = RTPROT_BOOT;
1159 rt->rt6i_protocol = cfg->fc_protocol;
1160
1161 addr_type = ipv6_addr_type(&cfg->fc_dst);
1162
1163 if (addr_type & IPV6_ADDR_MULTICAST)
1164 rt->u.dst.input = ip6_mc_input;
1165 else
1166 rt->u.dst.input = ip6_forward;
1167
1168 rt->u.dst.output = ip6_output;
1169
1170 ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1171 rt->rt6i_dst.plen = cfg->fc_dst_len;
1172 if (rt->rt6i_dst.plen == 128)
1173 rt->u.dst.flags = DST_HOST;
1174
1175#ifdef CONFIG_IPV6_SUBTREES
1176 ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1177 rt->rt6i_src.plen = cfg->fc_src_len;
1178#endif
1179
1180 rt->rt6i_metric = cfg->fc_metric;
1181
1182 /* We cannot add true routes via loopback here,
1183 they would result in kernel looping; promote them to reject routes
1184 */
1185 if ((cfg->fc_flags & RTF_REJECT) ||
1186 (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) {
1187 /* hold loopback dev/idev if we haven't done so. */
1188 if (dev != init_net.loopback_dev) {
1189 if (dev) {
1190 dev_put(dev);
1191 in6_dev_put(idev);
1192 }
1193 dev = init_net.loopback_dev;
1194 dev_hold(dev);
1195 idev = in6_dev_get(dev);
1196 if (!idev) {
1197 err = -ENODEV;
1198 goto out;
1199 }
1200 }
1201 rt->u.dst.output = ip6_pkt_discard_out;
1202 rt->u.dst.input = ip6_pkt_discard;
1203 rt->u.dst.error = -ENETUNREACH;
1204 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1205 goto install_route;
1206 }
1207
1208 if (cfg->fc_flags & RTF_GATEWAY) {
1209 struct in6_addr *gw_addr;
1210 int gwa_type;
1211
1212 gw_addr = &cfg->fc_gateway;
1213 ipv6_addr_copy(&rt->rt6i_gateway, gw_addr);
1214 gwa_type = ipv6_addr_type(gw_addr);
1215
1216 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1217 struct rt6_info *grt;
1218
1219 /* IPv6 strictly inhibits using not link-local
1220 addresses as nexthop address.
1221 Otherwise, router will not able to send redirects.
1222 It is very good, but in some (rare!) circumstances
1223 (SIT, PtP, NBMA NOARP links) it is handy to allow
1224 some exceptions. --ANK
1225 */
1226 err = -EINVAL;
1227 if (!(gwa_type&IPV6_ADDR_UNICAST))
1228 goto out;
1229
1230 grt = rt6_lookup(gw_addr, NULL, cfg->fc_ifindex, 1);
1231
1232 err = -EHOSTUNREACH;
1233 if (grt == NULL)
1234 goto out;
1235 if (dev) {
1236 if (dev != grt->rt6i_dev) {
1237 dst_release(&grt->u.dst);
1238 goto out;
1239 }
1240 } else {
1241 dev = grt->rt6i_dev;
1242 idev = grt->rt6i_idev;
1243 dev_hold(dev);
1244 in6_dev_hold(grt->rt6i_idev);
1245 }
1246 if (!(grt->rt6i_flags&RTF_GATEWAY))
1247 err = 0;
1248 dst_release(&grt->u.dst);
1249
1250 if (err)
1251 goto out;
1252 }
1253 err = -EINVAL;
1254 if (dev == NULL || (dev->flags&IFF_LOOPBACK))
1255 goto out;
1256 }
1257
1258 err = -ENODEV;
1259 if (dev == NULL)
1260 goto out;
1261
1262 if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) {
1263 rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev);
1264 if (IS_ERR(rt->rt6i_nexthop)) {
1265 err = PTR_ERR(rt->rt6i_nexthop);
1266 rt->rt6i_nexthop = NULL;
1267 goto out;
1268 }
1269 }
1270
1271 rt->rt6i_flags = cfg->fc_flags;
1272
1273install_route:
1274 if (cfg->fc_mx) {
1275 struct nlattr *nla;
1276 int remaining;
1277
1278 nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1279 int type = nla_type(nla);
1280
1281 if (type) {
1282 if (type > RTAX_MAX) {
1283 err = -EINVAL;
1284 goto out;
1285 }
1286
1287 rt->u.dst.metrics[type - 1] = nla_get_u32(nla);
1288 }
1289 }
1290 }
1291
1292 if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0)
1293 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1294 if (!rt->u.dst.metrics[RTAX_MTU-1])
1295 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev);
1296 if (!rt->u.dst.metrics[RTAX_ADVMSS-1])
1297 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1298 rt->u.dst.dev = dev;
1299 rt->rt6i_idev = idev;
1300 rt->rt6i_table = table;
1301 return __ip6_ins_rt(rt, &cfg->fc_nlinfo);
1302
1303out:
1304 if (dev)
1305 dev_put(dev);
1306 if (idev)
1307 in6_dev_put(idev);
1308 if (rt)
1309 dst_free(&rt->u.dst);
1310 return err;
1311}
1312
1313static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
1314{
1315 int err;
1316 struct fib6_table *table;
1317
1318 if (rt == &ip6_null_entry)
1319 return -ENOENT;
1320
1321 table = rt->rt6i_table;
1322 write_lock_bh(&table->tb6_lock);
1323
1324 err = fib6_del(rt, info);
1325 dst_release(&rt->u.dst);
1326
1327 write_unlock_bh(&table->tb6_lock);
1328
1329 return err;
1330}
1331
1332int ip6_del_rt(struct rt6_info *rt)
1333{
1334 return __ip6_del_rt(rt, NULL);
1335}
1336
1337static int ip6_route_del(struct fib6_config *cfg)
1338{
1339 struct fib6_table *table;
1340 struct fib6_node *fn;
1341 struct rt6_info *rt;
1342 int err = -ESRCH;
1343
1344 table = fib6_get_table(cfg->fc_table);
1345 if (table == NULL)
1346 return err;
1347
1348 read_lock_bh(&table->tb6_lock);
1349
1350 fn = fib6_locate(&table->tb6_root,
1351 &cfg->fc_dst, cfg->fc_dst_len,
1352 &cfg->fc_src, cfg->fc_src_len);
1353
1354 if (fn) {
1355 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1356 if (cfg->fc_ifindex &&
1357 (rt->rt6i_dev == NULL ||
1358 rt->rt6i_dev->ifindex != cfg->fc_ifindex))
1359 continue;
1360 if (cfg->fc_flags & RTF_GATEWAY &&
1361 !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
1362 continue;
1363 if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
1364 continue;
1365 dst_hold(&rt->u.dst);
1366 read_unlock_bh(&table->tb6_lock);
1367
1368 return __ip6_del_rt(rt, &cfg->fc_nlinfo);
1369 }
1370 }
1371 read_unlock_bh(&table->tb6_lock);
1372
1373 return err;
1374}
1375
1376/*
1377 * Handle redirects
1378 */
1379struct ip6rd_flowi {
1380 struct flowi fl;
1381 struct in6_addr gateway;
1382};
1383
1384static struct rt6_info *__ip6_route_redirect(struct fib6_table *table,
1385 struct flowi *fl,
1386 int flags)
1387{
1388 struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl;
1389 struct rt6_info *rt;
1390 struct fib6_node *fn;
1391
1392 /*
1393 * Get the "current" route for this destination and
1394 * check if the redirect has come from approriate router.
1395 *
1396 * RFC 2461 specifies that redirects should only be
1397 * accepted if they come from the nexthop to the target.
1398 * Due to the way the routes are chosen, this notion
1399 * is a bit fuzzy and one might need to check all possible
1400 * routes.
1401 */
1402
1403 read_lock_bh(&table->tb6_lock);
1404 fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src);
1405restart:
1406 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1407 /*
1408 * Current route is on-link; redirect is always invalid.
1409 *
1410 * Seems, previous statement is not true. It could
1411 * be node, which looks for us as on-link (f.e. proxy ndisc)
1412 * But then router serving it might decide, that we should
1413 * know truth 8)8) --ANK (980726).
1414 */
1415 if (rt6_check_expired(rt))
1416 continue;
1417 if (!(rt->rt6i_flags & RTF_GATEWAY))
1418 continue;
1419 if (fl->oif != rt->rt6i_dev->ifindex)
1420 continue;
1421 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1422 continue;
1423 break;
1424 }
1425
1426 if (!rt)
1427 rt = &ip6_null_entry;
1428 BACKTRACK(&fl->fl6_src);
1429out:
1430 dst_hold(&rt->u.dst);
1431
1432 read_unlock_bh(&table->tb6_lock);
1433
1434 return rt;
1435};
1436
1437static struct rt6_info *ip6_route_redirect(struct in6_addr *dest,
1438 struct in6_addr *src,
1439 struct in6_addr *gateway,
1440 struct net_device *dev)
1441{
1442 int flags = RT6_LOOKUP_F_HAS_SADDR;
1443 struct ip6rd_flowi rdfl = {
1444 .fl = {
1445 .oif = dev->ifindex,
1446 .nl_u = {
1447 .ip6_u = {
1448 .daddr = *dest,
1449 .saddr = *src,
1450 },
1451 },
1452 },
1453 .gateway = *gateway,
1454 };
1455
1456 if (rt6_need_strict(dest))
1457 flags |= RT6_LOOKUP_F_IFACE;
1458
1459 return (struct rt6_info *)fib6_rule_lookup((struct flowi *)&rdfl, flags, __ip6_route_redirect);
1460}
1461
1462void rt6_redirect(struct in6_addr *dest, struct in6_addr *src,
1463 struct in6_addr *saddr,
1464 struct neighbour *neigh, u8 *lladdr, int on_link)
1465{
1466 struct rt6_info *rt, *nrt = NULL;
1467 struct netevent_redirect netevent;
1468
1469 rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
1470
1471 if (rt == &ip6_null_entry) {
1472 if (net_ratelimit())
1473 printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop "
1474 "for redirect target\n");
1475 goto out;
1476 }
1477
1478 /*
1479 * We have finally decided to accept it.
1480 */
1481
1482 neigh_update(neigh, lladdr, NUD_STALE,
1483 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1484 NEIGH_UPDATE_F_OVERRIDE|
1485 (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1486 NEIGH_UPDATE_F_ISROUTER))
1487 );
1488
1489 /*
1490 * Redirect received -> path was valid.
1491 * Look, redirects are sent only in response to data packets,
1492 * so that this nexthop apparently is reachable. --ANK
1493 */
1494 dst_confirm(&rt->u.dst);
1495
1496 /* Duplicate redirect: silently ignore. */
1497 if (neigh == rt->u.dst.neighbour)
1498 goto out;
1499
1500 nrt = ip6_rt_copy(rt);
1501 if (nrt == NULL)
1502 goto out;
1503
1504 nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
1505 if (on_link)
1506 nrt->rt6i_flags &= ~RTF_GATEWAY;
1507
1508 ipv6_addr_copy(&nrt->rt6i_dst.addr, dest);
1509 nrt->rt6i_dst.plen = 128;
1510 nrt->u.dst.flags |= DST_HOST;
1511
1512 ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key);
1513 nrt->rt6i_nexthop = neigh_clone(neigh);
1514 /* Reset pmtu, it may be better */
1515 nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev);
1516 nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst));
1517
1518 if (ip6_ins_rt(nrt))
1519 goto out;
1520
1521 netevent.old = &rt->u.dst;
1522 netevent.new = &nrt->u.dst;
1523 call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
1524
1525 if (rt->rt6i_flags&RTF_CACHE) {
1526 ip6_del_rt(rt);
1527 return;
1528 }
1529
1530out:
1531 dst_release(&rt->u.dst);
1532 return;
1533}
1534
1535/*
1536 * Handle ICMP "packet too big" messages
1537 * i.e. Path MTU discovery
1538 */
1539
1540void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr,
1541 struct net_device *dev, u32 pmtu)
1542{
1543 struct rt6_info *rt, *nrt;
1544 int allfrag = 0;
1545
1546 rt = rt6_lookup(daddr, saddr, dev->ifindex, 0);
1547 if (rt == NULL)
1548 return;
1549
1550 if (pmtu >= dst_mtu(&rt->u.dst))
1551 goto out;
1552
1553 if (pmtu < IPV6_MIN_MTU) {
1554 /*
1555 * According to RFC2460, PMTU is set to the IPv6 Minimum Link
1556 * MTU (1280) and a fragment header should always be included
1557 * after a node receiving Too Big message reporting PMTU is
1558 * less than the IPv6 Minimum Link MTU.
1559 */
1560 pmtu = IPV6_MIN_MTU;
1561 allfrag = 1;
1562 }
1563
1564 /* New mtu received -> path was valid.
1565 They are sent only in response to data packets,
1566 so that this nexthop apparently is reachable. --ANK
1567 */
1568 dst_confirm(&rt->u.dst);
1569
1570 /* Host route. If it is static, it would be better
1571 not to override it, but add new one, so that
1572 when cache entry will expire old pmtu
1573 would return automatically.
1574 */
1575 if (rt->rt6i_flags & RTF_CACHE) {
1576 rt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1577 if (allfrag)
1578 rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1579 dst_set_expires(&rt->u.dst, ip6_rt_mtu_expires);
1580 rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES;
1581 goto out;
1582 }
1583
1584 /* Network route.
1585 Two cases are possible:
1586 1. It is connected route. Action: COW
1587 2. It is gatewayed route or NONEXTHOP route. Action: clone it.
1588 */
1589 if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP))
1590 nrt = rt6_alloc_cow(rt, daddr, saddr);
1591 else
1592 nrt = rt6_alloc_clone(rt, daddr);
1593
1594 if (nrt) {
1595 nrt->u.dst.metrics[RTAX_MTU-1] = pmtu;
1596 if (allfrag)
1597 nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG;
1598
1599 /* According to RFC 1981, detecting PMTU increase shouldn't be
1600 * happened within 5 mins, the recommended timer is 10 mins.
1601 * Here this route expiration time is set to ip6_rt_mtu_expires
1602 * which is 10 mins. After 10 mins the decreased pmtu is expired
1603 * and detecting PMTU increase will be automatically happened.
1604 */
1605 dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires);
1606 nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES;
1607
1608 ip6_ins_rt(nrt);
1609 }
1610out:
1611 dst_release(&rt->u.dst);
1612}
1613
1614/*
1615 * Misc support functions
1616 */
1617
1618static struct rt6_info * ip6_rt_copy(struct rt6_info *ort)
1619{
1620 struct rt6_info *rt = ip6_dst_alloc();
1621
1622 if (rt) {
1623 rt->u.dst.input = ort->u.dst.input;
1624 rt->u.dst.output = ort->u.dst.output;
1625
1626 memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
1627 rt->u.dst.error = ort->u.dst.error;
1628 rt->u.dst.dev = ort->u.dst.dev;
1629 if (rt->u.dst.dev)
1630 dev_hold(rt->u.dst.dev);
1631 rt->rt6i_idev = ort->rt6i_idev;
1632 if (rt->rt6i_idev)
1633 in6_dev_hold(rt->rt6i_idev);
1634 rt->u.dst.lastuse = jiffies;
1635 rt->rt6i_expires = 0;
1636
1637 ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway);
1638 rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES;
1639 rt->rt6i_metric = 0;
1640
1641 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1642#ifdef CONFIG_IPV6_SUBTREES
1643 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1644#endif
1645 rt->rt6i_table = ort->rt6i_table;
1646 }
1647 return rt;
1648}
1649
1650#ifdef CONFIG_IPV6_ROUTE_INFO
1651static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
1652 struct in6_addr *gwaddr, int ifindex)
1653{
1654 struct fib6_node *fn;
1655 struct rt6_info *rt = NULL;
1656 struct fib6_table *table;
1657
1658 table = fib6_get_table(RT6_TABLE_INFO);
1659 if (table == NULL)
1660 return NULL;
1661
1662 write_lock_bh(&table->tb6_lock);
1663 fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0);
1664 if (!fn)
1665 goto out;
1666
1667 for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) {
1668 if (rt->rt6i_dev->ifindex != ifindex)
1669 continue;
1670 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
1671 continue;
1672 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
1673 continue;
1674 dst_hold(&rt->u.dst);
1675 break;
1676 }
1677out:
1678 write_unlock_bh(&table->tb6_lock);
1679 return rt;
1680}
1681
1682static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
1683 struct in6_addr *gwaddr, int ifindex,
1684 unsigned pref)
1685{
1686 struct fib6_config cfg = {
1687 .fc_table = RT6_TABLE_INFO,
1688 .fc_metric = 1024,
1689 .fc_ifindex = ifindex,
1690 .fc_dst_len = prefixlen,
1691 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
1692 RTF_UP | RTF_PREF(pref),
1693 };
1694
1695 ipv6_addr_copy(&cfg.fc_dst, prefix);
1696 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1697
1698 /* We should treat it as a default route if prefix length is 0. */
1699 if (!prefixlen)
1700 cfg.fc_flags |= RTF_DEFAULT;
1701
1702 ip6_route_add(&cfg);
1703
1704 return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
1705}
1706#endif
1707
1708struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
1709{
1710 struct rt6_info *rt;
1711 struct fib6_table *table;
1712
1713 table = fib6_get_table(RT6_TABLE_DFLT);
1714 if (table == NULL)
1715 return NULL;
1716
1717 write_lock_bh(&table->tb6_lock);
1718 for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) {
1719 if (dev == rt->rt6i_dev &&
1720 ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
1721 ipv6_addr_equal(&rt->rt6i_gateway, addr))
1722 break;
1723 }
1724 if (rt)
1725 dst_hold(&rt->u.dst);
1726 write_unlock_bh(&table->tb6_lock);
1727 return rt;
1728}
1729
1730struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr,
1731 struct net_device *dev,
1732 unsigned int pref)
1733{
1734 struct fib6_config cfg = {
1735 .fc_table = RT6_TABLE_DFLT,
1736 .fc_metric = 1024,
1737 .fc_ifindex = dev->ifindex,
1738 .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
1739 RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
1740 };
1741
1742 ipv6_addr_copy(&cfg.fc_gateway, gwaddr);
1743
1744 ip6_route_add(&cfg);
1745
1746 return rt6_get_dflt_router(gwaddr, dev);
1747}
1748
1749void rt6_purge_dflt_routers(void)
1750{
1751 struct rt6_info *rt;
1752 struct fib6_table *table;
1753
1754 /* NOTE: Keep consistent with rt6_get_dflt_router */
1755 table = fib6_get_table(RT6_TABLE_DFLT);
1756 if (table == NULL)
1757 return;
1758
1759restart:
1760 read_lock_bh(&table->tb6_lock);
1761 for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) {
1762 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) {
1763 dst_hold(&rt->u.dst);
1764 read_unlock_bh(&table->tb6_lock);
1765 ip6_del_rt(rt);
1766 goto restart;
1767 }
1768 }
1769 read_unlock_bh(&table->tb6_lock);
1770}
1771
1772static void rtmsg_to_fib6_config(struct in6_rtmsg *rtmsg,
1773 struct fib6_config *cfg)
1774{
1775 memset(cfg, 0, sizeof(*cfg));
1776
1777 cfg->fc_table = RT6_TABLE_MAIN;
1778 cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
1779 cfg->fc_metric = rtmsg->rtmsg_metric;
1780 cfg->fc_expires = rtmsg->rtmsg_info;
1781 cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
1782 cfg->fc_src_len = rtmsg->rtmsg_src_len;
1783 cfg->fc_flags = rtmsg->rtmsg_flags;
1784
1785 ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst);
1786 ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src);
1787 ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway);
1788}
1789
1790int ipv6_route_ioctl(unsigned int cmd, void __user *arg)
1791{
1792 struct fib6_config cfg;
1793 struct in6_rtmsg rtmsg;
1794 int err;
1795
1796 switch(cmd) {
1797 case SIOCADDRT: /* Add a route */
1798 case SIOCDELRT: /* Delete a route */
1799 if (!capable(CAP_NET_ADMIN))
1800 return -EPERM;
1801 err = copy_from_user(&rtmsg, arg,
1802 sizeof(struct in6_rtmsg));
1803 if (err)
1804 return -EFAULT;
1805
1806 rtmsg_to_fib6_config(&rtmsg, &cfg);
1807
1808 rtnl_lock();
1809 switch (cmd) {
1810 case SIOCADDRT:
1811 err = ip6_route_add(&cfg);
1812 break;
1813 case SIOCDELRT:
1814 err = ip6_route_del(&cfg);
1815 break;
1816 default:
1817 err = -EINVAL;
1818 }
1819 rtnl_unlock();
1820
1821 return err;
1822 }
1823
1824 return -EINVAL;
1825}
1826
1827/*
1828 * Drop the packet on the floor
1829 */
1830
1831static inline int ip6_pkt_drop(struct sk_buff *skb, int code,
1832 int ipstats_mib_noroutes)
1833{
1834 int type;
1835 switch (ipstats_mib_noroutes) {
1836 case IPSTATS_MIB_INNOROUTES:
1837 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
1838 if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) {
1839 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INADDRERRORS);
1840 break;
1841 }
1842 /* FALLTHROUGH */
1843 case IPSTATS_MIB_OUTNOROUTES:
1844 IP6_INC_STATS(ip6_dst_idev(skb->dst), ipstats_mib_noroutes);
1845 break;
1846 }
1847 icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev);
1848 kfree_skb(skb);
1849 return 0;
1850}
1851
1852static int ip6_pkt_discard(struct sk_buff *skb)
1853{
1854 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
1855}
1856
1857static int ip6_pkt_discard_out(struct sk_buff *skb)
1858{
1859 skb->dev = skb->dst->dev;
1860 return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
1861}
1862
1863#ifdef CONFIG_IPV6_MULTIPLE_TABLES
1864
1865static int ip6_pkt_prohibit(struct sk_buff *skb)
1866{
1867 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
1868}
1869
1870static int ip6_pkt_prohibit_out(struct sk_buff *skb)
1871{
1872 skb->dev = skb->dst->dev;
1873 return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
1874}
1875
1876static int ip6_pkt_blk_hole(struct sk_buff *skb)
1877{
1878 kfree_skb(skb);
1879 return 0;
1880}
1881
1882#endif
1883
1884/*
1885 * Allocate a dst for local (unicast / anycast) address.
1886 */
1887
1888struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
1889 const struct in6_addr *addr,
1890 int anycast)
1891{
1892 struct rt6_info *rt = ip6_dst_alloc();
1893
1894 if (rt == NULL)
1895 return ERR_PTR(-ENOMEM);
1896
1897 dev_hold(init_net.loopback_dev);
1898 in6_dev_hold(idev);
1899
1900 rt->u.dst.flags = DST_HOST;
1901 rt->u.dst.input = ip6_input;
1902 rt->u.dst.output = ip6_output;
1903 rt->rt6i_dev = init_net.loopback_dev;
1904 rt->rt6i_idev = idev;
1905 rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev);
1906 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst));
1907 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1;
1908 rt->u.dst.obsolete = -1;
1909
1910 rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
1911 if (anycast)
1912 rt->rt6i_flags |= RTF_ANYCAST;
1913 else
1914 rt->rt6i_flags |= RTF_LOCAL;
1915 rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway);
1916 if (rt->rt6i_nexthop == NULL) {
1917 dst_free(&rt->u.dst);
1918 return ERR_PTR(-ENOMEM);
1919 }
1920
1921 ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
1922 rt->rt6i_dst.plen = 128;
1923 rt->rt6i_table = fib6_get_table(RT6_TABLE_LOCAL);
1924
1925 atomic_set(&rt->u.dst.__refcnt, 1);
1926
1927 return rt;
1928}
1929
1930static int fib6_ifdown(struct rt6_info *rt, void *arg)
1931{
1932 if (((void*)rt->rt6i_dev == arg || arg == NULL) &&
1933 rt != &ip6_null_entry) {
1934 RT6_TRACE("deleted by ifdown %p\n", rt);
1935 return -1;
1936 }
1937 return 0;
1938}
1939
1940void rt6_ifdown(struct net_device *dev)
1941{
1942 fib6_clean_all(fib6_ifdown, 0, dev);
1943}
1944
1945struct rt6_mtu_change_arg
1946{
1947 struct net_device *dev;
1948 unsigned mtu;
1949};
1950
1951static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
1952{
1953 struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
1954 struct inet6_dev *idev;
1955
1956 /* In IPv6 pmtu discovery is not optional,
1957 so that RTAX_MTU lock cannot disable it.
1958 We still use this lock to block changes
1959 caused by addrconf/ndisc.
1960 */
1961
1962 idev = __in6_dev_get(arg->dev);
1963 if (idev == NULL)
1964 return 0;
1965
1966 /* For administrative MTU increase, there is no way to discover
1967 IPv6 PMTU increase, so PMTU increase should be updated here.
1968 Since RFC 1981 doesn't include administrative MTU increase
1969 update PMTU increase is a MUST. (i.e. jumbo frame)
1970 */
1971 /*
1972 If new MTU is less than route PMTU, this new MTU will be the
1973 lowest MTU in the path, update the route PMTU to reflect PMTU
1974 decreases; if new MTU is greater than route PMTU, and the
1975 old MTU is the lowest MTU in the path, update the route PMTU
1976 to reflect the increase. In this case if the other nodes' MTU
1977 also have the lowest MTU, TOO BIG MESSAGE will be lead to
1978 PMTU discouvery.
1979 */
1980 if (rt->rt6i_dev == arg->dev &&
1981 !dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1982 (dst_mtu(&rt->u.dst) > arg->mtu ||
1983 (dst_mtu(&rt->u.dst) < arg->mtu &&
1984 dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) {
1985 rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu;
1986 rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu);
1987 }
1988 return 0;
1989}
1990
1991void rt6_mtu_change(struct net_device *dev, unsigned mtu)
1992{
1993 struct rt6_mtu_change_arg arg = {
1994 .dev = dev,
1995 .mtu = mtu,
1996 };
1997
1998 fib6_clean_all(rt6_mtu_change_route, 0, &arg);
1999}
2000
2001static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2002 [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
2003 [RTA_OIF] = { .type = NLA_U32 },
2004 [RTA_IIF] = { .type = NLA_U32 },
2005 [RTA_PRIORITY] = { .type = NLA_U32 },
2006 [RTA_METRICS] = { .type = NLA_NESTED },
2007};
2008
2009static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2010 struct fib6_config *cfg)
2011{
2012 struct rtmsg *rtm;
2013 struct nlattr *tb[RTA_MAX+1];
2014 int err;
2015
2016 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2017 if (err < 0)
2018 goto errout;
2019
2020 err = -EINVAL;
2021 rtm = nlmsg_data(nlh);
2022 memset(cfg, 0, sizeof(*cfg));
2023
2024 cfg->fc_table = rtm->rtm_table;
2025 cfg->fc_dst_len = rtm->rtm_dst_len;
2026 cfg->fc_src_len = rtm->rtm_src_len;
2027 cfg->fc_flags = RTF_UP;
2028 cfg->fc_protocol = rtm->rtm_protocol;
2029
2030 if (rtm->rtm_type == RTN_UNREACHABLE)
2031 cfg->fc_flags |= RTF_REJECT;
2032
2033 cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid;
2034 cfg->fc_nlinfo.nlh = nlh;
2035
2036 if (tb[RTA_GATEWAY]) {
2037 nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16);
2038 cfg->fc_flags |= RTF_GATEWAY;
2039 }
2040
2041 if (tb[RTA_DST]) {
2042 int plen = (rtm->rtm_dst_len + 7) >> 3;
2043
2044 if (nla_len(tb[RTA_DST]) < plen)
2045 goto errout;
2046
2047 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2048 }
2049
2050 if (tb[RTA_SRC]) {
2051 int plen = (rtm->rtm_src_len + 7) >> 3;
2052
2053 if (nla_len(tb[RTA_SRC]) < plen)
2054 goto errout;
2055
2056 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2057 }
2058
2059 if (tb[RTA_OIF])
2060 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2061
2062 if (tb[RTA_PRIORITY])
2063 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2064
2065 if (tb[RTA_METRICS]) {
2066 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2067 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2068 }
2069
2070 if (tb[RTA_TABLE])
2071 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2072
2073 err = 0;
2074errout:
2075 return err;
2076}
2077
2078static int inet6_rtm_delroute(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_del(&cfg);
2088}
2089
2090static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
2091{
2092 struct fib6_config cfg;
2093 int err;
2094
2095 err = rtm_to_fib6_config(skb, nlh, &cfg);
2096 if (err < 0)
2097 return err;
2098
2099 return ip6_route_add(&cfg);
2100}
2101
2102static inline size_t rt6_nlmsg_size(void)
2103{
2104 return NLMSG_ALIGN(sizeof(struct rtmsg))
2105 + nla_total_size(16) /* RTA_SRC */
2106 + nla_total_size(16) /* RTA_DST */
2107 + nla_total_size(16) /* RTA_GATEWAY */
2108 + nla_total_size(16) /* RTA_PREFSRC */
2109 + nla_total_size(4) /* RTA_TABLE */
2110 + nla_total_size(4) /* RTA_IIF */
2111 + nla_total_size(4) /* RTA_OIF */
2112 + nla_total_size(4) /* RTA_PRIORITY */
2113 + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
2114 + nla_total_size(sizeof(struct rta_cacheinfo));
2115}
2116
2117static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
2118 struct in6_addr *dst, struct in6_addr *src,
2119 int iif, int type, u32 pid, u32 seq,
2120 int prefix, unsigned int flags)
2121{
2122 struct rtmsg *rtm;
2123 struct nlmsghdr *nlh;
2124 long expires;
2125 u32 table;
2126
2127 if (prefix) { /* user wants prefix routes only */
2128 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
2129 /* success since this is not a prefix route */
2130 return 1;
2131 }
2132 }
2133
2134 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags);
2135 if (nlh == NULL)
2136 return -EMSGSIZE;
2137
2138 rtm = nlmsg_data(nlh);
2139 rtm->rtm_family = AF_INET6;
2140 rtm->rtm_dst_len = rt->rt6i_dst.plen;
2141 rtm->rtm_src_len = rt->rt6i_src.plen;
2142 rtm->rtm_tos = 0;
2143 if (rt->rt6i_table)
2144 table = rt->rt6i_table->tb6_id;
2145 else
2146 table = RT6_TABLE_UNSPEC;
2147 rtm->rtm_table = table;
2148 NLA_PUT_U32(skb, RTA_TABLE, table);
2149 if (rt->rt6i_flags&RTF_REJECT)
2150 rtm->rtm_type = RTN_UNREACHABLE;
2151 else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK))
2152 rtm->rtm_type = RTN_LOCAL;
2153 else
2154 rtm->rtm_type = RTN_UNICAST;
2155 rtm->rtm_flags = 0;
2156 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
2157 rtm->rtm_protocol = rt->rt6i_protocol;
2158 if (rt->rt6i_flags&RTF_DYNAMIC)
2159 rtm->rtm_protocol = RTPROT_REDIRECT;
2160 else if (rt->rt6i_flags & RTF_ADDRCONF)
2161 rtm->rtm_protocol = RTPROT_KERNEL;
2162 else if (rt->rt6i_flags&RTF_DEFAULT)
2163 rtm->rtm_protocol = RTPROT_RA;
2164
2165 if (rt->rt6i_flags&RTF_CACHE)
2166 rtm->rtm_flags |= RTM_F_CLONED;
2167
2168 if (dst) {
2169 NLA_PUT(skb, RTA_DST, 16, dst);
2170 rtm->rtm_dst_len = 128;
2171 } else if (rtm->rtm_dst_len)
2172 NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr);
2173#ifdef CONFIG_IPV6_SUBTREES
2174 if (src) {
2175 NLA_PUT(skb, RTA_SRC, 16, src);
2176 rtm->rtm_src_len = 128;
2177 } else if (rtm->rtm_src_len)
2178 NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr);
2179#endif
2180 if (iif)
2181 NLA_PUT_U32(skb, RTA_IIF, iif);
2182 else if (dst) {
2183 struct in6_addr saddr_buf;
2184 if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0)
2185 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
2186 }
2187
2188 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2189 goto nla_put_failure;
2190
2191 if (rt->u.dst.neighbour)
2192 NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key);
2193
2194 if (rt->u.dst.dev)
2195 NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex);
2196
2197 NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric);
2198
2199 expires = rt->rt6i_expires ? rt->rt6i_expires - jiffies : 0;
2200 if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0,
2201 expires, rt->u.dst.error) < 0)
2202 goto nla_put_failure;
2203
2204 return nlmsg_end(skb, nlh);
2205
2206nla_put_failure:
2207 nlmsg_cancel(skb, nlh);
2208 return -EMSGSIZE;
2209}
2210
2211int rt6_dump_route(struct rt6_info *rt, void *p_arg)
2212{
2213 struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
2214 int prefix;
2215
2216 if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
2217 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
2218 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
2219 } else
2220 prefix = 0;
2221
2222 return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
2223 NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq,
2224 prefix, NLM_F_MULTI);
2225}
2226
2227static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2228{
2229 struct nlattr *tb[RTA_MAX+1];
2230 struct rt6_info *rt;
2231 struct sk_buff *skb;
2232 struct rtmsg *rtm;
2233 struct flowi fl;
2234 int err, iif = 0;
2235
2236 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2237 if (err < 0)
2238 goto errout;
2239
2240 err = -EINVAL;
2241 memset(&fl, 0, sizeof(fl));
2242
2243 if (tb[RTA_SRC]) {
2244 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
2245 goto errout;
2246
2247 ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC]));
2248 }
2249
2250 if (tb[RTA_DST]) {
2251 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
2252 goto errout;
2253
2254 ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST]));
2255 }
2256
2257 if (tb[RTA_IIF])
2258 iif = nla_get_u32(tb[RTA_IIF]);
2259
2260 if (tb[RTA_OIF])
2261 fl.oif = nla_get_u32(tb[RTA_OIF]);
2262
2263 if (iif) {
2264 struct net_device *dev;
2265 dev = __dev_get_by_index(&init_net, iif);
2266 if (!dev) {
2267 err = -ENODEV;
2268 goto errout;
2269 }
2270 }
2271
2272 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2273 if (skb == NULL) {
2274 err = -ENOBUFS;
2275 goto errout;
2276 }
2277
2278 /* Reserve room for dummy headers, this skb can pass
2279 through good chunk of routing engine.
2280 */
2281 skb_reset_mac_header(skb);
2282 skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
2283
2284 rt = (struct rt6_info*) ip6_route_output(NULL, &fl);
2285 skb->dst = &rt->u.dst;
2286
2287 err = rt6_fill_node(skb, rt, &fl.fl6_dst, &fl.fl6_src, iif,
2288 RTM_NEWROUTE, NETLINK_CB(in_skb).pid,
2289 nlh->nlmsg_seq, 0, 0);
2290 if (err < 0) {
2291 kfree_skb(skb);
2292 goto errout;
2293 }
2294
2295 err = rtnl_unicast(skb, NETLINK_CB(in_skb).pid);
2296errout:
2297 return err;
2298}
2299
2300void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
2301{
2302 struct sk_buff *skb;
2303 u32 pid = 0, seq = 0;
2304 struct nlmsghdr *nlh = NULL;
2305 int err = -ENOBUFS;
2306
2307 if (info) {
2308 pid = info->pid;
2309 nlh = info->nlh;
2310 if (nlh)
2311 seq = nlh->nlmsg_seq;
2312 }
2313
2314 skb = nlmsg_new(rt6_nlmsg_size(), gfp_any());
2315 if (skb == NULL)
2316 goto errout;
2317
2318 err = rt6_fill_node(skb, rt, NULL, NULL, 0, event, pid, seq, 0, 0);
2319 if (err < 0) {
2320 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
2321 WARN_ON(err == -EMSGSIZE);
2322 kfree_skb(skb);
2323 goto errout;
2324 }
2325 err = rtnl_notify(skb, pid, RTNLGRP_IPV6_ROUTE, nlh, gfp_any());
2326errout:
2327 if (err < 0)
2328 rtnl_set_sk_err(RTNLGRP_IPV6_ROUTE, err);
2329}
2330
2331/*
2332 * /proc
2333 */
2334
2335#ifdef CONFIG_PROC_FS
2336
2337#define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1)
2338
2339struct rt6_proc_arg
2340{
2341 char *buffer;
2342 int offset;
2343 int length;
2344 int skip;
2345 int len;
2346};
2347
2348static int rt6_info_route(struct rt6_info *rt, void *p_arg)
2349{
2350 struct rt6_proc_arg *arg = (struct rt6_proc_arg *) p_arg;
2351
2352 if (arg->skip < arg->offset / RT6_INFO_LEN) {
2353 arg->skip++;
2354 return 0;
2355 }
2356
2357 if (arg->len >= arg->length)
2358 return 0;
2359
2360 arg->len += sprintf(arg->buffer + arg->len,
2361 NIP6_SEQFMT " %02x ",
2362 NIP6(rt->rt6i_dst.addr),
2363 rt->rt6i_dst.plen);
2364
2365#ifdef CONFIG_IPV6_SUBTREES
2366 arg->len += sprintf(arg->buffer + arg->len,
2367 NIP6_SEQFMT " %02x ",
2368 NIP6(rt->rt6i_src.addr),
2369 rt->rt6i_src.plen);
2370#else
2371 arg->len += sprintf(arg->buffer + arg->len,
2372 "00000000000000000000000000000000 00 ");
2373#endif
2374
2375 if (rt->rt6i_nexthop) {
2376 arg->len += sprintf(arg->buffer + arg->len,
2377 NIP6_SEQFMT,
2378 NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key)));
2379 } else {
2380 arg->len += sprintf(arg->buffer + arg->len,
2381 "00000000000000000000000000000000");
2382 }
2383 arg->len += sprintf(arg->buffer + arg->len,
2384 " %08x %08x %08x %08x %8s\n",
2385 rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt),
2386 rt->u.dst.__use, rt->rt6i_flags,
2387 rt->rt6i_dev ? rt->rt6i_dev->name : "");
2388 return 0;
2389}
2390
2391static int rt6_proc_info(char *buffer, char **start, off_t offset, int length)
2392{
2393 struct rt6_proc_arg arg = {
2394 .buffer = buffer,
2395 .offset = offset,
2396 .length = length,
2397 };
2398
2399 fib6_clean_all(rt6_info_route, 0, &arg);
2400
2401 *start = buffer;
2402 if (offset)
2403 *start += offset % RT6_INFO_LEN;
2404
2405 arg.len -= offset % RT6_INFO_LEN;
2406
2407 if (arg.len > length)
2408 arg.len = length;
2409 if (arg.len < 0)
2410 arg.len = 0;
2411
2412 return arg.len;
2413}
2414
2415static int rt6_stats_seq_show(struct seq_file *seq, void *v)
2416{
2417 seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
2418 rt6_stats.fib_nodes, rt6_stats.fib_route_nodes,
2419 rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries,
2420 rt6_stats.fib_rt_cache,
2421 atomic_read(&ip6_dst_ops.entries),
2422 rt6_stats.fib_discarded_routes);
2423
2424 return 0;
2425}
2426
2427static int rt6_stats_seq_open(struct inode *inode, struct file *file)
2428{
2429 return single_open(file, rt6_stats_seq_show, NULL);
2430}
2431
2432static const struct file_operations rt6_stats_seq_fops = {
2433 .owner = THIS_MODULE,
2434 .open = rt6_stats_seq_open,
2435 .read = seq_read,
2436 .llseek = seq_lseek,
2437 .release = single_release,
2438};
2439#endif /* CONFIG_PROC_FS */
2440
2441#ifdef CONFIG_SYSCTL
2442
2443static int flush_delay;
2444
2445static
2446int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp,
2447 void __user *buffer, size_t *lenp, loff_t *ppos)
2448{
2449 if (write) {
2450 proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
2451 fib6_run_gc(flush_delay <= 0 ? ~0UL : (unsigned long)flush_delay);
2452 return 0;
2453 } else
2454 return -EINVAL;
2455}
2456
2457ctl_table ipv6_route_table[] = {
2458 {
2459 .ctl_name = NET_IPV6_ROUTE_FLUSH,
2460 .procname = "flush",
2461 .data = &flush_delay,
2462 .maxlen = sizeof(int),
2463 .mode = 0200,
2464 .proc_handler = &ipv6_sysctl_rtcache_flush
2465 },
2466 {
2467 .ctl_name = NET_IPV6_ROUTE_GC_THRESH,
2468 .procname = "gc_thresh",
2469 .data = &ip6_dst_ops.gc_thresh,
2470 .maxlen = sizeof(int),
2471 .mode = 0644,
2472 .proc_handler = &proc_dointvec,
2473 },
2474 {
2475 .ctl_name = NET_IPV6_ROUTE_MAX_SIZE,
2476 .procname = "max_size",
2477 .data = &ip6_rt_max_size,
2478 .maxlen = sizeof(int),
2479 .mode = 0644,
2480 .proc_handler = &proc_dointvec,
2481 },
2482 {
2483 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL,
2484 .procname = "gc_min_interval",
2485 .data = &ip6_rt_gc_min_interval,
2486 .maxlen = sizeof(int),
2487 .mode = 0644,
2488 .proc_handler = &proc_dointvec_jiffies,
2489 .strategy = &sysctl_jiffies,
2490 },
2491 {
2492 .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT,
2493 .procname = "gc_timeout",
2494 .data = &ip6_rt_gc_timeout,
2495 .maxlen = sizeof(int),
2496 .mode = 0644,
2497 .proc_handler = &proc_dointvec_jiffies,
2498 .strategy = &sysctl_jiffies,
2499 },
2500 {
2501 .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL,
2502 .procname = "gc_interval",
2503 .data = &ip6_rt_gc_interval,
2504 .maxlen = sizeof(int),
2505 .mode = 0644,
2506 .proc_handler = &proc_dointvec_jiffies,
2507 .strategy = &sysctl_jiffies,
2508 },
2509 {
2510 .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY,
2511 .procname = "gc_elasticity",
2512 .data = &ip6_rt_gc_elasticity,
2513 .maxlen = sizeof(int),
2514 .mode = 0644,
2515 .proc_handler = &proc_dointvec_jiffies,
2516 .strategy = &sysctl_jiffies,
2517 },
2518 {
2519 .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES,
2520 .procname = "mtu_expires",
2521 .data = &ip6_rt_mtu_expires,
2522 .maxlen = sizeof(int),
2523 .mode = 0644,
2524 .proc_handler = &proc_dointvec_jiffies,
2525 .strategy = &sysctl_jiffies,
2526 },
2527 {
2528 .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS,
2529 .procname = "min_adv_mss",
2530 .data = &ip6_rt_min_advmss,
2531 .maxlen = sizeof(int),
2532 .mode = 0644,
2533 .proc_handler = &proc_dointvec_jiffies,
2534 .strategy = &sysctl_jiffies,
2535 },
2536 {
2537 .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS,
2538 .procname = "gc_min_interval_ms",
2539 .data = &ip6_rt_gc_min_interval,
2540 .maxlen = sizeof(int),
2541 .mode = 0644,
2542 .proc_handler = &proc_dointvec_ms_jiffies,
2543 .strategy = &sysctl_ms_jiffies,
2544 },
2545 { .ctl_name = 0 }
2546};
2547
2548#endif
2549
2550void __init ip6_route_init(void)
2551{
2552#ifdef CONFIG_PROC_FS
2553 struct proc_dir_entry *p;
2554#endif
2555 ip6_dst_ops.kmem_cachep =
2556 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
2557 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
2558 ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops.kmem_cachep;
2559
2560 fib6_init();
2561#ifdef CONFIG_PROC_FS
2562 p = proc_net_create(&init_net, "ipv6_route", 0, rt6_proc_info);
2563 if (p)
2564 p->owner = THIS_MODULE;
2565
2566 proc_net_fops_create(&init_net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops);
2567#endif
2568#ifdef CONFIG_XFRM
2569 xfrm6_init();
2570#endif
2571#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2572 fib6_rules_init();
2573#endif
2574
2575 __rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL);
2576 __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL);
2577 __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL);
2578}
2579
2580void ip6_route_cleanup(void)
2581{
2582#ifdef CONFIG_IPV6_MULTIPLE_TABLES
2583 fib6_rules_cleanup();
2584#endif
2585#ifdef CONFIG_PROC_FS
2586 proc_net_remove(&init_net, "ipv6_route");
2587 proc_net_remove(&init_net, "rt6_stats");
2588#endif
2589#ifdef CONFIG_XFRM
2590 xfrm6_fini();
2591#endif
2592 rt6_ifdown(NULL);
2593 fib6_gc_cleanup();
2594 kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
2595}
Clone of davem's net-next-2.6 tree