Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 | */ | |
26 | ||
27 | #include <linux/config.h> | |
28 | #include <linux/errno.h> | |
29 | #include <linux/types.h> | |
30 | #include <linux/times.h> | |
31 | #include <linux/socket.h> | |
32 | #include <linux/sockios.h> | |
33 | #include <linux/net.h> | |
34 | #include <linux/route.h> | |
35 | #include <linux/netdevice.h> | |
36 | #include <linux/in6.h> | |
37 | #include <linux/init.h> | |
38 | #include <linux/netlink.h> | |
39 | #include <linux/if_arp.h> | |
40 | ||
41 | #ifdef CONFIG_PROC_FS | |
42 | #include <linux/proc_fs.h> | |
43 | #include <linux/seq_file.h> | |
44 | #endif | |
45 | ||
46 | #include <net/snmp.h> | |
47 | #include <net/ipv6.h> | |
48 | #include <net/ip6_fib.h> | |
49 | #include <net/ip6_route.h> | |
50 | #include <net/ndisc.h> | |
51 | #include <net/addrconf.h> | |
52 | #include <net/tcp.h> | |
53 | #include <linux/rtnetlink.h> | |
54 | #include <net/dst.h> | |
55 | #include <net/xfrm.h> | |
56 | ||
57 | #include <asm/uaccess.h> | |
58 | ||
59 | #ifdef CONFIG_SYSCTL | |
60 | #include <linux/sysctl.h> | |
61 | #endif | |
62 | ||
63 | /* Set to 3 to get tracing. */ | |
64 | #define RT6_DEBUG 2 | |
65 | ||
66 | #if RT6_DEBUG >= 3 | |
67 | #define RDBG(x) printk x | |
68 | #define RT6_TRACE(x...) printk(KERN_DEBUG x) | |
69 | #else | |
70 | #define RDBG(x) | |
71 | #define RT6_TRACE(x...) do { ; } while (0) | |
72 | #endif | |
73 | ||
74 | ||
75 | static int ip6_rt_max_size = 4096; | |
76 | static int ip6_rt_gc_min_interval = HZ / 2; | |
77 | static int ip6_rt_gc_timeout = 60*HZ; | |
78 | int ip6_rt_gc_interval = 30*HZ; | |
79 | static int ip6_rt_gc_elasticity = 9; | |
80 | static int ip6_rt_mtu_expires = 10*60*HZ; | |
81 | static int ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40; | |
82 | ||
83 | static struct rt6_info * ip6_rt_copy(struct rt6_info *ort); | |
84 | static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); | |
85 | static struct dst_entry *ip6_negative_advice(struct dst_entry *); | |
86 | static void ip6_dst_destroy(struct dst_entry *); | |
87 | static void ip6_dst_ifdown(struct dst_entry *, | |
88 | struct net_device *dev, int how); | |
89 | static int ip6_dst_gc(void); | |
90 | ||
91 | static int ip6_pkt_discard(struct sk_buff *skb); | |
92 | static int ip6_pkt_discard_out(struct sk_buff *skb); | |
93 | static void ip6_link_failure(struct sk_buff *skb); | |
94 | static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu); | |
95 | ||
96 | static struct dst_ops ip6_dst_ops = { | |
97 | .family = AF_INET6, | |
98 | .protocol = __constant_htons(ETH_P_IPV6), | |
99 | .gc = ip6_dst_gc, | |
100 | .gc_thresh = 1024, | |
101 | .check = ip6_dst_check, | |
102 | .destroy = ip6_dst_destroy, | |
103 | .ifdown = ip6_dst_ifdown, | |
104 | .negative_advice = ip6_negative_advice, | |
105 | .link_failure = ip6_link_failure, | |
106 | .update_pmtu = ip6_rt_update_pmtu, | |
107 | .entry_size = sizeof(struct rt6_info), | |
108 | }; | |
109 | ||
110 | struct rt6_info ip6_null_entry = { | |
111 | .u = { | |
112 | .dst = { | |
113 | .__refcnt = ATOMIC_INIT(1), | |
114 | .__use = 1, | |
115 | .dev = &loopback_dev, | |
116 | .obsolete = -1, | |
117 | .error = -ENETUNREACH, | |
118 | .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, | |
119 | .input = ip6_pkt_discard, | |
120 | .output = ip6_pkt_discard_out, | |
121 | .ops = &ip6_dst_ops, | |
122 | .path = (struct dst_entry*)&ip6_null_entry, | |
123 | } | |
124 | }, | |
125 | .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), | |
126 | .rt6i_metric = ~(u32) 0, | |
127 | .rt6i_ref = ATOMIC_INIT(1), | |
128 | }; | |
129 | ||
130 | struct fib6_node ip6_routing_table = { | |
131 | .leaf = &ip6_null_entry, | |
132 | .fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO, | |
133 | }; | |
134 | ||
135 | /* Protects all the ip6 fib */ | |
136 | ||
137 | DEFINE_RWLOCK(rt6_lock); | |
138 | ||
139 | ||
140 | /* allocate dst with ip6_dst_ops */ | |
141 | static __inline__ struct rt6_info *ip6_dst_alloc(void) | |
142 | { | |
143 | return (struct rt6_info *)dst_alloc(&ip6_dst_ops); | |
144 | } | |
145 | ||
146 | static void ip6_dst_destroy(struct dst_entry *dst) | |
147 | { | |
148 | struct rt6_info *rt = (struct rt6_info *)dst; | |
149 | struct inet6_dev *idev = rt->rt6i_idev; | |
150 | ||
151 | if (idev != NULL) { | |
152 | rt->rt6i_idev = NULL; | |
153 | in6_dev_put(idev); | |
154 | } | |
155 | } | |
156 | ||
157 | static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, | |
158 | int how) | |
159 | { | |
160 | struct rt6_info *rt = (struct rt6_info *)dst; | |
161 | struct inet6_dev *idev = rt->rt6i_idev; | |
162 | ||
163 | if (dev != &loopback_dev && idev != NULL && idev->dev == dev) { | |
164 | struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev); | |
165 | if (loopback_idev != NULL) { | |
166 | rt->rt6i_idev = loopback_idev; | |
167 | in6_dev_put(idev); | |
168 | } | |
169 | } | |
170 | } | |
171 | ||
172 | static __inline__ int rt6_check_expired(const struct rt6_info *rt) | |
173 | { | |
174 | return (rt->rt6i_flags & RTF_EXPIRES && | |
175 | time_after(jiffies, rt->rt6i_expires)); | |
176 | } | |
177 | ||
178 | /* | |
179 | * Route lookup. Any rt6_lock is implied. | |
180 | */ | |
181 | ||
182 | static __inline__ struct rt6_info *rt6_device_match(struct rt6_info *rt, | |
183 | int oif, | |
184 | int strict) | |
185 | { | |
186 | struct rt6_info *local = NULL; | |
187 | struct rt6_info *sprt; | |
188 | ||
189 | if (oif) { | |
190 | for (sprt = rt; sprt; sprt = sprt->u.next) { | |
191 | struct net_device *dev = sprt->rt6i_dev; | |
192 | if (dev->ifindex == oif) | |
193 | return sprt; | |
194 | if (dev->flags & IFF_LOOPBACK) { | |
195 | if (sprt->rt6i_idev == NULL || | |
196 | sprt->rt6i_idev->dev->ifindex != oif) { | |
197 | if (strict && oif) | |
198 | continue; | |
199 | if (local && (!oif || | |
200 | local->rt6i_idev->dev->ifindex == oif)) | |
201 | continue; | |
202 | } | |
203 | local = sprt; | |
204 | } | |
205 | } | |
206 | ||
207 | if (local) | |
208 | return local; | |
209 | ||
210 | if (strict) | |
211 | return &ip6_null_entry; | |
212 | } | |
213 | return rt; | |
214 | } | |
215 | ||
216 | /* | |
217 | * pointer to the last default router chosen. BH is disabled locally. | |
218 | */ | |
219 | static struct rt6_info *rt6_dflt_pointer; | |
220 | static DEFINE_SPINLOCK(rt6_dflt_lock); | |
221 | ||
222 | void rt6_reset_dflt_pointer(struct rt6_info *rt) | |
223 | { | |
224 | spin_lock_bh(&rt6_dflt_lock); | |
225 | if (rt == NULL || rt == rt6_dflt_pointer) { | |
226 | RT6_TRACE("reset default router: %p->NULL\n", rt6_dflt_pointer); | |
227 | rt6_dflt_pointer = NULL; | |
228 | } | |
229 | spin_unlock_bh(&rt6_dflt_lock); | |
230 | } | |
231 | ||
232 | /* Default Router Selection (RFC 2461 6.3.6) */ | |
233 | static struct rt6_info *rt6_best_dflt(struct rt6_info *rt, int oif) | |
234 | { | |
235 | struct rt6_info *match = NULL; | |
236 | struct rt6_info *sprt; | |
237 | int mpri = 0; | |
238 | ||
239 | for (sprt = rt; sprt; sprt = sprt->u.next) { | |
240 | struct neighbour *neigh; | |
241 | int m = 0; | |
242 | ||
243 | if (!oif || | |
244 | (sprt->rt6i_dev && | |
245 | sprt->rt6i_dev->ifindex == oif)) | |
246 | m += 8; | |
247 | ||
248 | if (rt6_check_expired(sprt)) | |
249 | continue; | |
250 | ||
251 | if (sprt == rt6_dflt_pointer) | |
252 | m += 4; | |
253 | ||
254 | if ((neigh = sprt->rt6i_nexthop) != NULL) { | |
255 | read_lock_bh(&neigh->lock); | |
256 | switch (neigh->nud_state) { | |
257 | case NUD_REACHABLE: | |
258 | m += 3; | |
259 | break; | |
260 | ||
261 | case NUD_STALE: | |
262 | case NUD_DELAY: | |
263 | case NUD_PROBE: | |
264 | m += 2; | |
265 | break; | |
266 | ||
267 | case NUD_NOARP: | |
268 | case NUD_PERMANENT: | |
269 | m += 1; | |
270 | break; | |
271 | ||
272 | case NUD_INCOMPLETE: | |
273 | default: | |
274 | read_unlock_bh(&neigh->lock); | |
275 | continue; | |
276 | } | |
277 | read_unlock_bh(&neigh->lock); | |
278 | } else { | |
279 | continue; | |
280 | } | |
281 | ||
282 | if (m > mpri || m >= 12) { | |
283 | match = sprt; | |
284 | mpri = m; | |
285 | if (m >= 12) { | |
286 | /* we choose the last default router if it | |
287 | * is in (probably) reachable state. | |
288 | * If route changed, we should do pmtu | |
289 | * discovery. --yoshfuji | |
290 | */ | |
291 | break; | |
292 | } | |
293 | } | |
294 | } | |
295 | ||
296 | spin_lock(&rt6_dflt_lock); | |
297 | if (!match) { | |
298 | /* | |
299 | * No default routers are known to be reachable. | |
300 | * SHOULD round robin | |
301 | */ | |
302 | if (rt6_dflt_pointer) { | |
303 | for (sprt = rt6_dflt_pointer->u.next; | |
304 | sprt; sprt = sprt->u.next) { | |
305 | if (sprt->u.dst.obsolete <= 0 && | |
306 | sprt->u.dst.error == 0 && | |
307 | !rt6_check_expired(sprt)) { | |
308 | match = sprt; | |
309 | break; | |
310 | } | |
311 | } | |
312 | for (sprt = rt; | |
313 | !match && sprt; | |
314 | sprt = sprt->u.next) { | |
315 | if (sprt->u.dst.obsolete <= 0 && | |
316 | sprt->u.dst.error == 0 && | |
317 | !rt6_check_expired(sprt)) { | |
318 | match = sprt; | |
319 | break; | |
320 | } | |
321 | if (sprt == rt6_dflt_pointer) | |
322 | break; | |
323 | } | |
324 | } | |
325 | } | |
326 | ||
327 | if (match) { | |
328 | if (rt6_dflt_pointer != match) | |
329 | RT6_TRACE("changed default router: %p->%p\n", | |
330 | rt6_dflt_pointer, match); | |
331 | rt6_dflt_pointer = match; | |
332 | } | |
333 | spin_unlock(&rt6_dflt_lock); | |
334 | ||
335 | if (!match) { | |
336 | /* | |
337 | * Last Resort: if no default routers found, | |
338 | * use addrconf default route. | |
339 | * We don't record this route. | |
340 | */ | |
341 | for (sprt = ip6_routing_table.leaf; | |
342 | sprt; sprt = sprt->u.next) { | |
343 | if (!rt6_check_expired(sprt) && | |
344 | (sprt->rt6i_flags & RTF_DEFAULT) && | |
345 | (!oif || | |
346 | (sprt->rt6i_dev && | |
347 | sprt->rt6i_dev->ifindex == oif))) { | |
348 | match = sprt; | |
349 | break; | |
350 | } | |
351 | } | |
352 | if (!match) { | |
353 | /* no default route. give up. */ | |
354 | match = &ip6_null_entry; | |
355 | } | |
356 | } | |
357 | ||
358 | return match; | |
359 | } | |
360 | ||
361 | struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr, | |
362 | int oif, int strict) | |
363 | { | |
364 | struct fib6_node *fn; | |
365 | struct rt6_info *rt; | |
366 | ||
367 | read_lock_bh(&rt6_lock); | |
368 | fn = fib6_lookup(&ip6_routing_table, daddr, saddr); | |
369 | rt = rt6_device_match(fn->leaf, oif, strict); | |
370 | dst_hold(&rt->u.dst); | |
371 | rt->u.dst.__use++; | |
372 | read_unlock_bh(&rt6_lock); | |
373 | ||
374 | rt->u.dst.lastuse = jiffies; | |
375 | if (rt->u.dst.error == 0) | |
376 | return rt; | |
377 | dst_release(&rt->u.dst); | |
378 | return NULL; | |
379 | } | |
380 | ||
381 | /* ip6_ins_rt is called with FREE rt6_lock. | |
382 | It takes new route entry, the addition fails by any reason the | |
383 | route is freed. In any case, if caller does not hold it, it may | |
384 | be destroyed. | |
385 | */ | |
386 | ||
387 | int ip6_ins_rt(struct rt6_info *rt, struct nlmsghdr *nlh, void *_rtattr) | |
388 | { | |
389 | int err; | |
390 | ||
391 | write_lock_bh(&rt6_lock); | |
392 | err = fib6_add(&ip6_routing_table, rt, nlh, _rtattr); | |
393 | write_unlock_bh(&rt6_lock); | |
394 | ||
395 | return err; | |
396 | } | |
397 | ||
398 | /* No rt6_lock! If COW failed, the function returns dead route entry | |
399 | with dst->error set to errno value. | |
400 | */ | |
401 | ||
402 | static struct rt6_info *rt6_cow(struct rt6_info *ort, struct in6_addr *daddr, | |
403 | struct in6_addr *saddr) | |
404 | { | |
405 | int err; | |
406 | struct rt6_info *rt; | |
407 | ||
408 | /* | |
409 | * Clone the route. | |
410 | */ | |
411 | ||
412 | rt = ip6_rt_copy(ort); | |
413 | ||
414 | if (rt) { | |
415 | ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); | |
416 | ||
417 | if (!(rt->rt6i_flags&RTF_GATEWAY)) | |
418 | ipv6_addr_copy(&rt->rt6i_gateway, daddr); | |
419 | ||
420 | rt->rt6i_dst.plen = 128; | |
421 | rt->rt6i_flags |= RTF_CACHE; | |
422 | rt->u.dst.flags |= DST_HOST; | |
423 | ||
424 | #ifdef CONFIG_IPV6_SUBTREES | |
425 | if (rt->rt6i_src.plen && saddr) { | |
426 | ipv6_addr_copy(&rt->rt6i_src.addr, saddr); | |
427 | rt->rt6i_src.plen = 128; | |
428 | } | |
429 | #endif | |
430 | ||
431 | rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway); | |
432 | ||
433 | dst_hold(&rt->u.dst); | |
434 | ||
435 | err = ip6_ins_rt(rt, NULL, NULL); | |
436 | if (err == 0) | |
437 | return rt; | |
438 | ||
439 | rt->u.dst.error = err; | |
440 | ||
441 | return rt; | |
442 | } | |
443 | dst_hold(&ip6_null_entry.u.dst); | |
444 | return &ip6_null_entry; | |
445 | } | |
446 | ||
447 | #define BACKTRACK() \ | |
448 | if (rt == &ip6_null_entry && strict) { \ | |
449 | while ((fn = fn->parent) != NULL) { \ | |
450 | if (fn->fn_flags & RTN_ROOT) { \ | |
451 | dst_hold(&rt->u.dst); \ | |
452 | goto out; \ | |
453 | } \ | |
454 | if (fn->fn_flags & RTN_RTINFO) \ | |
455 | goto restart; \ | |
456 | } \ | |
457 | } | |
458 | ||
459 | ||
460 | void ip6_route_input(struct sk_buff *skb) | |
461 | { | |
462 | struct fib6_node *fn; | |
463 | struct rt6_info *rt; | |
464 | int strict; | |
465 | int attempts = 3; | |
466 | ||
467 | strict = ipv6_addr_type(&skb->nh.ipv6h->daddr) & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL); | |
468 | ||
469 | relookup: | |
470 | read_lock_bh(&rt6_lock); | |
471 | ||
472 | fn = fib6_lookup(&ip6_routing_table, &skb->nh.ipv6h->daddr, | |
473 | &skb->nh.ipv6h->saddr); | |
474 | ||
475 | restart: | |
476 | rt = fn->leaf; | |
477 | ||
478 | if ((rt->rt6i_flags & RTF_CACHE)) { | |
479 | rt = rt6_device_match(rt, skb->dev->ifindex, strict); | |
480 | BACKTRACK(); | |
481 | dst_hold(&rt->u.dst); | |
482 | goto out; | |
483 | } | |
484 | ||
485 | rt = rt6_device_match(rt, skb->dev->ifindex, 0); | |
486 | BACKTRACK(); | |
487 | ||
488 | if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) { | |
489 | struct rt6_info *nrt; | |
490 | dst_hold(&rt->u.dst); | |
491 | read_unlock_bh(&rt6_lock); | |
492 | ||
493 | nrt = rt6_cow(rt, &skb->nh.ipv6h->daddr, | |
494 | &skb->nh.ipv6h->saddr); | |
495 | ||
496 | dst_release(&rt->u.dst); | |
497 | rt = nrt; | |
498 | ||
499 | if (rt->u.dst.error != -EEXIST || --attempts <= 0) | |
500 | goto out2; | |
501 | ||
502 | /* Race condition! In the gap, when rt6_lock was | |
503 | released someone could insert this route. Relookup. | |
504 | */ | |
505 | dst_release(&rt->u.dst); | |
506 | goto relookup; | |
507 | } | |
508 | dst_hold(&rt->u.dst); | |
509 | ||
510 | out: | |
511 | read_unlock_bh(&rt6_lock); | |
512 | out2: | |
513 | rt->u.dst.lastuse = jiffies; | |
514 | rt->u.dst.__use++; | |
515 | skb->dst = (struct dst_entry *) rt; | |
516 | } | |
517 | ||
518 | struct dst_entry * ip6_route_output(struct sock *sk, struct flowi *fl) | |
519 | { | |
520 | struct fib6_node *fn; | |
521 | struct rt6_info *rt; | |
522 | int strict; | |
523 | int attempts = 3; | |
524 | ||
525 | strict = ipv6_addr_type(&fl->fl6_dst) & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL); | |
526 | ||
527 | relookup: | |
528 | read_lock_bh(&rt6_lock); | |
529 | ||
530 | fn = fib6_lookup(&ip6_routing_table, &fl->fl6_dst, &fl->fl6_src); | |
531 | ||
532 | restart: | |
533 | rt = fn->leaf; | |
534 | ||
535 | if ((rt->rt6i_flags & RTF_CACHE)) { | |
536 | rt = rt6_device_match(rt, fl->oif, strict); | |
537 | BACKTRACK(); | |
538 | dst_hold(&rt->u.dst); | |
539 | goto out; | |
540 | } | |
541 | if (rt->rt6i_flags & RTF_DEFAULT) { | |
542 | if (rt->rt6i_metric >= IP6_RT_PRIO_ADDRCONF) | |
543 | rt = rt6_best_dflt(rt, fl->oif); | |
544 | } else { | |
545 | rt = rt6_device_match(rt, fl->oif, strict); | |
546 | BACKTRACK(); | |
547 | } | |
548 | ||
549 | if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) { | |
550 | struct rt6_info *nrt; | |
551 | dst_hold(&rt->u.dst); | |
552 | read_unlock_bh(&rt6_lock); | |
553 | ||
554 | nrt = rt6_cow(rt, &fl->fl6_dst, &fl->fl6_src); | |
555 | ||
556 | dst_release(&rt->u.dst); | |
557 | rt = nrt; | |
558 | ||
559 | if (rt->u.dst.error != -EEXIST || --attempts <= 0) | |
560 | goto out2; | |
561 | ||
562 | /* Race condition! In the gap, when rt6_lock was | |
563 | released someone could insert this route. Relookup. | |
564 | */ | |
565 | dst_release(&rt->u.dst); | |
566 | goto relookup; | |
567 | } | |
568 | dst_hold(&rt->u.dst); | |
569 | ||
570 | out: | |
571 | read_unlock_bh(&rt6_lock); | |
572 | out2: | |
573 | rt->u.dst.lastuse = jiffies; | |
574 | rt->u.dst.__use++; | |
575 | return &rt->u.dst; | |
576 | } | |
577 | ||
578 | ||
579 | /* | |
580 | * Destination cache support functions | |
581 | */ | |
582 | ||
583 | static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie) | |
584 | { | |
585 | struct rt6_info *rt; | |
586 | ||
587 | rt = (struct rt6_info *) dst; | |
588 | ||
589 | if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) | |
590 | return dst; | |
591 | ||
592 | return NULL; | |
593 | } | |
594 | ||
595 | static struct dst_entry *ip6_negative_advice(struct dst_entry *dst) | |
596 | { | |
597 | struct rt6_info *rt = (struct rt6_info *) dst; | |
598 | ||
599 | if (rt) { | |
600 | if (rt->rt6i_flags & RTF_CACHE) | |
601 | ip6_del_rt(rt, NULL, NULL); | |
602 | else | |
603 | dst_release(dst); | |
604 | } | |
605 | return NULL; | |
606 | } | |
607 | ||
608 | static void ip6_link_failure(struct sk_buff *skb) | |
609 | { | |
610 | struct rt6_info *rt; | |
611 | ||
612 | icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev); | |
613 | ||
614 | rt = (struct rt6_info *) skb->dst; | |
615 | if (rt) { | |
616 | if (rt->rt6i_flags&RTF_CACHE) { | |
617 | dst_set_expires(&rt->u.dst, 0); | |
618 | rt->rt6i_flags |= RTF_EXPIRES; | |
619 | } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) | |
620 | rt->rt6i_node->fn_sernum = -1; | |
621 | } | |
622 | } | |
623 | ||
624 | static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu) | |
625 | { | |
626 | struct rt6_info *rt6 = (struct rt6_info*)dst; | |
627 | ||
628 | if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) { | |
629 | rt6->rt6i_flags |= RTF_MODIFIED; | |
630 | if (mtu < IPV6_MIN_MTU) { | |
631 | mtu = IPV6_MIN_MTU; | |
632 | dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; | |
633 | } | |
634 | dst->metrics[RTAX_MTU-1] = mtu; | |
635 | } | |
636 | } | |
637 | ||
638 | /* Protected by rt6_lock. */ | |
639 | static struct dst_entry *ndisc_dst_gc_list; | |
640 | static int ipv6_get_mtu(struct net_device *dev); | |
641 | ||
642 | static inline unsigned int ipv6_advmss(unsigned int mtu) | |
643 | { | |
644 | mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr); | |
645 | ||
646 | if (mtu < ip6_rt_min_advmss) | |
647 | mtu = ip6_rt_min_advmss; | |
648 | ||
649 | /* | |
650 | * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and | |
651 | * corresponding MSS is IPV6_MAXPLEN - tcp_header_size. | |
652 | * IPV6_MAXPLEN is also valid and means: "any MSS, | |
653 | * rely only on pmtu discovery" | |
654 | */ | |
655 | if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr)) | |
656 | mtu = IPV6_MAXPLEN; | |
657 | return mtu; | |
658 | } | |
659 | ||
660 | struct dst_entry *ndisc_dst_alloc(struct net_device *dev, | |
661 | struct neighbour *neigh, | |
662 | struct in6_addr *addr, | |
663 | int (*output)(struct sk_buff *)) | |
664 | { | |
665 | struct rt6_info *rt; | |
666 | struct inet6_dev *idev = in6_dev_get(dev); | |
667 | ||
668 | if (unlikely(idev == NULL)) | |
669 | return NULL; | |
670 | ||
671 | rt = ip6_dst_alloc(); | |
672 | if (unlikely(rt == NULL)) { | |
673 | in6_dev_put(idev); | |
674 | goto out; | |
675 | } | |
676 | ||
677 | dev_hold(dev); | |
678 | if (neigh) | |
679 | neigh_hold(neigh); | |
680 | else | |
681 | neigh = ndisc_get_neigh(dev, addr); | |
682 | ||
683 | rt->rt6i_dev = dev; | |
684 | rt->rt6i_idev = idev; | |
685 | rt->rt6i_nexthop = neigh; | |
686 | atomic_set(&rt->u.dst.__refcnt, 1); | |
687 | rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255; | |
688 | rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); | |
689 | rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst)); | |
690 | rt->u.dst.output = output; | |
691 | ||
692 | #if 0 /* there's no chance to use these for ndisc */ | |
693 | rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST | |
694 | ? DST_HOST | |
695 | : 0; | |
696 | ipv6_addr_copy(&rt->rt6i_dst.addr, addr); | |
697 | rt->rt6i_dst.plen = 128; | |
698 | #endif | |
699 | ||
700 | write_lock_bh(&rt6_lock); | |
701 | rt->u.dst.next = ndisc_dst_gc_list; | |
702 | ndisc_dst_gc_list = &rt->u.dst; | |
703 | write_unlock_bh(&rt6_lock); | |
704 | ||
705 | fib6_force_start_gc(); | |
706 | ||
707 | out: | |
708 | return (struct dst_entry *)rt; | |
709 | } | |
710 | ||
711 | int ndisc_dst_gc(int *more) | |
712 | { | |
713 | struct dst_entry *dst, *next, **pprev; | |
714 | int freed; | |
715 | ||
716 | next = NULL; | |
717 | pprev = &ndisc_dst_gc_list; | |
718 | freed = 0; | |
719 | while ((dst = *pprev) != NULL) { | |
720 | if (!atomic_read(&dst->__refcnt)) { | |
721 | *pprev = dst->next; | |
722 | dst_free(dst); | |
723 | freed++; | |
724 | } else { | |
725 | pprev = &dst->next; | |
726 | (*more)++; | |
727 | } | |
728 | } | |
729 | ||
730 | return freed; | |
731 | } | |
732 | ||
733 | static int ip6_dst_gc(void) | |
734 | { | |
735 | static unsigned expire = 30*HZ; | |
736 | static unsigned long last_gc; | |
737 | unsigned long now = jiffies; | |
738 | ||
739 | if (time_after(last_gc + ip6_rt_gc_min_interval, now) && | |
740 | atomic_read(&ip6_dst_ops.entries) <= ip6_rt_max_size) | |
741 | goto out; | |
742 | ||
743 | expire++; | |
744 | fib6_run_gc(expire); | |
745 | last_gc = now; | |
746 | if (atomic_read(&ip6_dst_ops.entries) < ip6_dst_ops.gc_thresh) | |
747 | expire = ip6_rt_gc_timeout>>1; | |
748 | ||
749 | out: | |
750 | expire -= expire>>ip6_rt_gc_elasticity; | |
751 | return (atomic_read(&ip6_dst_ops.entries) > ip6_rt_max_size); | |
752 | } | |
753 | ||
754 | /* Clean host part of a prefix. Not necessary in radix tree, | |
755 | but results in cleaner routing tables. | |
756 | ||
757 | Remove it only when all the things will work! | |
758 | */ | |
759 | ||
760 | static int ipv6_get_mtu(struct net_device *dev) | |
761 | { | |
762 | int mtu = IPV6_MIN_MTU; | |
763 | struct inet6_dev *idev; | |
764 | ||
765 | idev = in6_dev_get(dev); | |
766 | if (idev) { | |
767 | mtu = idev->cnf.mtu6; | |
768 | in6_dev_put(idev); | |
769 | } | |
770 | return mtu; | |
771 | } | |
772 | ||
773 | int ipv6_get_hoplimit(struct net_device *dev) | |
774 | { | |
775 | int hoplimit = ipv6_devconf.hop_limit; | |
776 | struct inet6_dev *idev; | |
777 | ||
778 | idev = in6_dev_get(dev); | |
779 | if (idev) { | |
780 | hoplimit = idev->cnf.hop_limit; | |
781 | in6_dev_put(idev); | |
782 | } | |
783 | return hoplimit; | |
784 | } | |
785 | ||
786 | /* | |
787 | * | |
788 | */ | |
789 | ||
790 | int ip6_route_add(struct in6_rtmsg *rtmsg, struct nlmsghdr *nlh, void *_rtattr) | |
791 | { | |
792 | int err; | |
793 | struct rtmsg *r; | |
794 | struct rtattr **rta; | |
795 | struct rt6_info *rt = NULL; | |
796 | struct net_device *dev = NULL; | |
797 | struct inet6_dev *idev = NULL; | |
798 | int addr_type; | |
799 | ||
800 | rta = (struct rtattr **) _rtattr; | |
801 | ||
802 | if (rtmsg->rtmsg_dst_len > 128 || rtmsg->rtmsg_src_len > 128) | |
803 | return -EINVAL; | |
804 | #ifndef CONFIG_IPV6_SUBTREES | |
805 | if (rtmsg->rtmsg_src_len) | |
806 | return -EINVAL; | |
807 | #endif | |
808 | if (rtmsg->rtmsg_ifindex) { | |
809 | err = -ENODEV; | |
810 | dev = dev_get_by_index(rtmsg->rtmsg_ifindex); | |
811 | if (!dev) | |
812 | goto out; | |
813 | idev = in6_dev_get(dev); | |
814 | if (!idev) | |
815 | goto out; | |
816 | } | |
817 | ||
818 | if (rtmsg->rtmsg_metric == 0) | |
819 | rtmsg->rtmsg_metric = IP6_RT_PRIO_USER; | |
820 | ||
821 | rt = ip6_dst_alloc(); | |
822 | ||
823 | if (rt == NULL) { | |
824 | err = -ENOMEM; | |
825 | goto out; | |
826 | } | |
827 | ||
828 | rt->u.dst.obsolete = -1; | |
829 | rt->rt6i_expires = clock_t_to_jiffies(rtmsg->rtmsg_info); | |
830 | if (nlh && (r = NLMSG_DATA(nlh))) { | |
831 | rt->rt6i_protocol = r->rtm_protocol; | |
832 | } else { | |
833 | rt->rt6i_protocol = RTPROT_BOOT; | |
834 | } | |
835 | ||
836 | addr_type = ipv6_addr_type(&rtmsg->rtmsg_dst); | |
837 | ||
838 | if (addr_type & IPV6_ADDR_MULTICAST) | |
839 | rt->u.dst.input = ip6_mc_input; | |
840 | else | |
841 | rt->u.dst.input = ip6_forward; | |
842 | ||
843 | rt->u.dst.output = ip6_output; | |
844 | ||
845 | ipv6_addr_prefix(&rt->rt6i_dst.addr, | |
846 | &rtmsg->rtmsg_dst, rtmsg->rtmsg_dst_len); | |
847 | rt->rt6i_dst.plen = rtmsg->rtmsg_dst_len; | |
848 | if (rt->rt6i_dst.plen == 128) | |
849 | rt->u.dst.flags = DST_HOST; | |
850 | ||
851 | #ifdef CONFIG_IPV6_SUBTREES | |
852 | ipv6_addr_prefix(&rt->rt6i_src.addr, | |
853 | &rtmsg->rtmsg_src, rtmsg->rtmsg_src_len); | |
854 | rt->rt6i_src.plen = rtmsg->rtmsg_src_len; | |
855 | #endif | |
856 | ||
857 | rt->rt6i_metric = rtmsg->rtmsg_metric; | |
858 | ||
859 | /* We cannot add true routes via loopback here, | |
860 | they would result in kernel looping; promote them to reject routes | |
861 | */ | |
862 | if ((rtmsg->rtmsg_flags&RTF_REJECT) || | |
863 | (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) { | |
864 | /* hold loopback dev/idev if we haven't done so. */ | |
865 | if (dev != &loopback_dev) { | |
866 | if (dev) { | |
867 | dev_put(dev); | |
868 | in6_dev_put(idev); | |
869 | } | |
870 | dev = &loopback_dev; | |
871 | dev_hold(dev); | |
872 | idev = in6_dev_get(dev); | |
873 | if (!idev) { | |
874 | err = -ENODEV; | |
875 | goto out; | |
876 | } | |
877 | } | |
878 | rt->u.dst.output = ip6_pkt_discard_out; | |
879 | rt->u.dst.input = ip6_pkt_discard; | |
880 | rt->u.dst.error = -ENETUNREACH; | |
881 | rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP; | |
882 | goto install_route; | |
883 | } | |
884 | ||
885 | if (rtmsg->rtmsg_flags & RTF_GATEWAY) { | |
886 | struct in6_addr *gw_addr; | |
887 | int gwa_type; | |
888 | ||
889 | gw_addr = &rtmsg->rtmsg_gateway; | |
890 | ipv6_addr_copy(&rt->rt6i_gateway, &rtmsg->rtmsg_gateway); | |
891 | gwa_type = ipv6_addr_type(gw_addr); | |
892 | ||
893 | if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { | |
894 | struct rt6_info *grt; | |
895 | ||
896 | /* IPv6 strictly inhibits using not link-local | |
897 | addresses as nexthop address. | |
898 | Otherwise, router will not able to send redirects. | |
899 | It is very good, but in some (rare!) circumstances | |
900 | (SIT, PtP, NBMA NOARP links) it is handy to allow | |
901 | some exceptions. --ANK | |
902 | */ | |
903 | err = -EINVAL; | |
904 | if (!(gwa_type&IPV6_ADDR_UNICAST)) | |
905 | goto out; | |
906 | ||
907 | grt = rt6_lookup(gw_addr, NULL, rtmsg->rtmsg_ifindex, 1); | |
908 | ||
909 | err = -EHOSTUNREACH; | |
910 | if (grt == NULL) | |
911 | goto out; | |
912 | if (dev) { | |
913 | if (dev != grt->rt6i_dev) { | |
914 | dst_release(&grt->u.dst); | |
915 | goto out; | |
916 | } | |
917 | } else { | |
918 | dev = grt->rt6i_dev; | |
919 | idev = grt->rt6i_idev; | |
920 | dev_hold(dev); | |
921 | in6_dev_hold(grt->rt6i_idev); | |
922 | } | |
923 | if (!(grt->rt6i_flags&RTF_GATEWAY)) | |
924 | err = 0; | |
925 | dst_release(&grt->u.dst); | |
926 | ||
927 | if (err) | |
928 | goto out; | |
929 | } | |
930 | err = -EINVAL; | |
931 | if (dev == NULL || (dev->flags&IFF_LOOPBACK)) | |
932 | goto out; | |
933 | } | |
934 | ||
935 | err = -ENODEV; | |
936 | if (dev == NULL) | |
937 | goto out; | |
938 | ||
939 | if (rtmsg->rtmsg_flags & (RTF_GATEWAY|RTF_NONEXTHOP)) { | |
940 | rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev); | |
941 | if (IS_ERR(rt->rt6i_nexthop)) { | |
942 | err = PTR_ERR(rt->rt6i_nexthop); | |
943 | rt->rt6i_nexthop = NULL; | |
944 | goto out; | |
945 | } | |
946 | } | |
947 | ||
948 | rt->rt6i_flags = rtmsg->rtmsg_flags; | |
949 | ||
950 | install_route: | |
951 | if (rta && rta[RTA_METRICS-1]) { | |
952 | int attrlen = RTA_PAYLOAD(rta[RTA_METRICS-1]); | |
953 | struct rtattr *attr = RTA_DATA(rta[RTA_METRICS-1]); | |
954 | ||
955 | while (RTA_OK(attr, attrlen)) { | |
956 | unsigned flavor = attr->rta_type; | |
957 | if (flavor) { | |
958 | if (flavor > RTAX_MAX) { | |
959 | err = -EINVAL; | |
960 | goto out; | |
961 | } | |
962 | rt->u.dst.metrics[flavor-1] = | |
963 | *(u32 *)RTA_DATA(attr); | |
964 | } | |
965 | attr = RTA_NEXT(attr, attrlen); | |
966 | } | |
967 | } | |
968 | ||
969 | if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0) | |
970 | rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1; | |
971 | if (!rt->u.dst.metrics[RTAX_MTU-1]) | |
972 | rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev); | |
973 | if (!rt->u.dst.metrics[RTAX_ADVMSS-1]) | |
974 | rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst)); | |
975 | rt->u.dst.dev = dev; | |
976 | rt->rt6i_idev = idev; | |
977 | return ip6_ins_rt(rt, nlh, _rtattr); | |
978 | ||
979 | out: | |
980 | if (dev) | |
981 | dev_put(dev); | |
982 | if (idev) | |
983 | in6_dev_put(idev); | |
984 | if (rt) | |
985 | dst_free((struct dst_entry *) rt); | |
986 | return err; | |
987 | } | |
988 | ||
989 | int ip6_del_rt(struct rt6_info *rt, struct nlmsghdr *nlh, void *_rtattr) | |
990 | { | |
991 | int err; | |
992 | ||
993 | write_lock_bh(&rt6_lock); | |
994 | ||
995 | rt6_reset_dflt_pointer(NULL); | |
996 | ||
997 | err = fib6_del(rt, nlh, _rtattr); | |
998 | dst_release(&rt->u.dst); | |
999 | ||
1000 | write_unlock_bh(&rt6_lock); | |
1001 | ||
1002 | return err; | |
1003 | } | |
1004 | ||
1005 | static int ip6_route_del(struct in6_rtmsg *rtmsg, struct nlmsghdr *nlh, void *_rtattr) | |
1006 | { | |
1007 | struct fib6_node *fn; | |
1008 | struct rt6_info *rt; | |
1009 | int err = -ESRCH; | |
1010 | ||
1011 | read_lock_bh(&rt6_lock); | |
1012 | ||
1013 | fn = fib6_locate(&ip6_routing_table, | |
1014 | &rtmsg->rtmsg_dst, rtmsg->rtmsg_dst_len, | |
1015 | &rtmsg->rtmsg_src, rtmsg->rtmsg_src_len); | |
1016 | ||
1017 | if (fn) { | |
1018 | for (rt = fn->leaf; rt; rt = rt->u.next) { | |
1019 | if (rtmsg->rtmsg_ifindex && | |
1020 | (rt->rt6i_dev == NULL || | |
1021 | rt->rt6i_dev->ifindex != rtmsg->rtmsg_ifindex)) | |
1022 | continue; | |
1023 | if (rtmsg->rtmsg_flags&RTF_GATEWAY && | |
1024 | !ipv6_addr_equal(&rtmsg->rtmsg_gateway, &rt->rt6i_gateway)) | |
1025 | continue; | |
1026 | if (rtmsg->rtmsg_metric && | |
1027 | rtmsg->rtmsg_metric != rt->rt6i_metric) | |
1028 | continue; | |
1029 | dst_hold(&rt->u.dst); | |
1030 | read_unlock_bh(&rt6_lock); | |
1031 | ||
1032 | return ip6_del_rt(rt, nlh, _rtattr); | |
1033 | } | |
1034 | } | |
1035 | read_unlock_bh(&rt6_lock); | |
1036 | ||
1037 | return err; | |
1038 | } | |
1039 | ||
1040 | /* | |
1041 | * Handle redirects | |
1042 | */ | |
1043 | void rt6_redirect(struct in6_addr *dest, struct in6_addr *saddr, | |
1044 | struct neighbour *neigh, u8 *lladdr, int on_link) | |
1045 | { | |
1046 | struct rt6_info *rt, *nrt; | |
1047 | ||
1048 | /* Locate old route to this destination. */ | |
1049 | rt = rt6_lookup(dest, NULL, neigh->dev->ifindex, 1); | |
1050 | ||
1051 | if (rt == NULL) | |
1052 | return; | |
1053 | ||
1054 | if (neigh->dev != rt->rt6i_dev) | |
1055 | goto out; | |
1056 | ||
1057 | /* | |
1058 | * Current route is on-link; redirect is always invalid. | |
1059 | * | |
1060 | * Seems, previous statement is not true. It could | |
1061 | * be node, which looks for us as on-link (f.e. proxy ndisc) | |
1062 | * But then router serving it might decide, that we should | |
1063 | * know truth 8)8) --ANK (980726). | |
1064 | */ | |
1065 | if (!(rt->rt6i_flags&RTF_GATEWAY)) | |
1066 | goto out; | |
1067 | ||
1068 | /* | |
1069 | * RFC 2461 specifies that redirects should only be | |
1070 | * accepted if they come from the nexthop to the target. | |
1071 | * Due to the way default routers are chosen, this notion | |
1072 | * is a bit fuzzy and one might need to check all default | |
1073 | * routers. | |
1074 | */ | |
1075 | if (!ipv6_addr_equal(saddr, &rt->rt6i_gateway)) { | |
1076 | if (rt->rt6i_flags & RTF_DEFAULT) { | |
1077 | struct rt6_info *rt1; | |
1078 | ||
1079 | read_lock(&rt6_lock); | |
1080 | for (rt1 = ip6_routing_table.leaf; rt1; rt1 = rt1->u.next) { | |
1081 | if (ipv6_addr_equal(saddr, &rt1->rt6i_gateway)) { | |
1082 | dst_hold(&rt1->u.dst); | |
1083 | dst_release(&rt->u.dst); | |
1084 | read_unlock(&rt6_lock); | |
1085 | rt = rt1; | |
1086 | goto source_ok; | |
1087 | } | |
1088 | } | |
1089 | read_unlock(&rt6_lock); | |
1090 | } | |
1091 | if (net_ratelimit()) | |
1092 | printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop " | |
1093 | "for redirect target\n"); | |
1094 | goto out; | |
1095 | } | |
1096 | ||
1097 | source_ok: | |
1098 | ||
1099 | /* | |
1100 | * We have finally decided to accept it. | |
1101 | */ | |
1102 | ||
1103 | neigh_update(neigh, lladdr, NUD_STALE, | |
1104 | NEIGH_UPDATE_F_WEAK_OVERRIDE| | |
1105 | NEIGH_UPDATE_F_OVERRIDE| | |
1106 | (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER| | |
1107 | NEIGH_UPDATE_F_ISROUTER)) | |
1108 | ); | |
1109 | ||
1110 | /* | |
1111 | * Redirect received -> path was valid. | |
1112 | * Look, redirects are sent only in response to data packets, | |
1113 | * so that this nexthop apparently is reachable. --ANK | |
1114 | */ | |
1115 | dst_confirm(&rt->u.dst); | |
1116 | ||
1117 | /* Duplicate redirect: silently ignore. */ | |
1118 | if (neigh == rt->u.dst.neighbour) | |
1119 | goto out; | |
1120 | ||
1121 | nrt = ip6_rt_copy(rt); | |
1122 | if (nrt == NULL) | |
1123 | goto out; | |
1124 | ||
1125 | nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE; | |
1126 | if (on_link) | |
1127 | nrt->rt6i_flags &= ~RTF_GATEWAY; | |
1128 | ||
1129 | ipv6_addr_copy(&nrt->rt6i_dst.addr, dest); | |
1130 | nrt->rt6i_dst.plen = 128; | |
1131 | nrt->u.dst.flags |= DST_HOST; | |
1132 | ||
1133 | ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key); | |
1134 | nrt->rt6i_nexthop = neigh_clone(neigh); | |
1135 | /* Reset pmtu, it may be better */ | |
1136 | nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev); | |
1137 | nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&nrt->u.dst)); | |
1138 | ||
1139 | if (ip6_ins_rt(nrt, NULL, NULL)) | |
1140 | goto out; | |
1141 | ||
1142 | if (rt->rt6i_flags&RTF_CACHE) { | |
1143 | ip6_del_rt(rt, NULL, NULL); | |
1144 | return; | |
1145 | } | |
1146 | ||
1147 | out: | |
1148 | dst_release(&rt->u.dst); | |
1149 | return; | |
1150 | } | |
1151 | ||
1152 | /* | |
1153 | * Handle ICMP "packet too big" messages | |
1154 | * i.e. Path MTU discovery | |
1155 | */ | |
1156 | ||
1157 | void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr, | |
1158 | struct net_device *dev, u32 pmtu) | |
1159 | { | |
1160 | struct rt6_info *rt, *nrt; | |
1161 | int allfrag = 0; | |
1162 | ||
1163 | rt = rt6_lookup(daddr, saddr, dev->ifindex, 0); | |
1164 | if (rt == NULL) | |
1165 | return; | |
1166 | ||
1167 | if (pmtu >= dst_mtu(&rt->u.dst)) | |
1168 | goto out; | |
1169 | ||
1170 | if (pmtu < IPV6_MIN_MTU) { | |
1171 | /* | |
1172 | * According to RFC2460, PMTU is set to the IPv6 Minimum Link | |
1173 | * MTU (1280) and a fragment header should always be included | |
1174 | * after a node receiving Too Big message reporting PMTU is | |
1175 | * less than the IPv6 Minimum Link MTU. | |
1176 | */ | |
1177 | pmtu = IPV6_MIN_MTU; | |
1178 | allfrag = 1; | |
1179 | } | |
1180 | ||
1181 | /* New mtu received -> path was valid. | |
1182 | They are sent only in response to data packets, | |
1183 | so that this nexthop apparently is reachable. --ANK | |
1184 | */ | |
1185 | dst_confirm(&rt->u.dst); | |
1186 | ||
1187 | /* Host route. If it is static, it would be better | |
1188 | not to override it, but add new one, so that | |
1189 | when cache entry will expire old pmtu | |
1190 | would return automatically. | |
1191 | */ | |
1192 | if (rt->rt6i_flags & RTF_CACHE) { | |
1193 | rt->u.dst.metrics[RTAX_MTU-1] = pmtu; | |
1194 | if (allfrag) | |
1195 | rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; | |
1196 | dst_set_expires(&rt->u.dst, ip6_rt_mtu_expires); | |
1197 | rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES; | |
1198 | goto out; | |
1199 | } | |
1200 | ||
1201 | /* Network route. | |
1202 | Two cases are possible: | |
1203 | 1. It is connected route. Action: COW | |
1204 | 2. It is gatewayed route or NONEXTHOP route. Action: clone it. | |
1205 | */ | |
1206 | if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) { | |
1207 | nrt = rt6_cow(rt, daddr, saddr); | |
1208 | if (!nrt->u.dst.error) { | |
1209 | nrt->u.dst.metrics[RTAX_MTU-1] = pmtu; | |
1210 | if (allfrag) | |
1211 | nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; | |
1212 | /* According to RFC 1981, detecting PMTU increase shouldn't be | |
1213 | happened within 5 mins, the recommended timer is 10 mins. | |
1214 | Here this route expiration time is set to ip6_rt_mtu_expires | |
1215 | which is 10 mins. After 10 mins the decreased pmtu is expired | |
1216 | and detecting PMTU increase will be automatically happened. | |
1217 | */ | |
1218 | dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires); | |
1219 | nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES; | |
1220 | } | |
1221 | dst_release(&nrt->u.dst); | |
1222 | } else { | |
1223 | nrt = ip6_rt_copy(rt); | |
1224 | if (nrt == NULL) | |
1225 | goto out; | |
1226 | ipv6_addr_copy(&nrt->rt6i_dst.addr, daddr); | |
1227 | nrt->rt6i_dst.plen = 128; | |
1228 | nrt->u.dst.flags |= DST_HOST; | |
1229 | nrt->rt6i_nexthop = neigh_clone(rt->rt6i_nexthop); | |
1230 | dst_set_expires(&nrt->u.dst, ip6_rt_mtu_expires); | |
1231 | nrt->rt6i_flags |= RTF_DYNAMIC|RTF_CACHE|RTF_EXPIRES; | |
1232 | nrt->u.dst.metrics[RTAX_MTU-1] = pmtu; | |
1233 | if (allfrag) | |
1234 | nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; | |
1235 | ip6_ins_rt(nrt, NULL, NULL); | |
1236 | } | |
1237 | ||
1238 | out: | |
1239 | dst_release(&rt->u.dst); | |
1240 | } | |
1241 | ||
1242 | /* | |
1243 | * Misc support functions | |
1244 | */ | |
1245 | ||
1246 | static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) | |
1247 | { | |
1248 | struct rt6_info *rt = ip6_dst_alloc(); | |
1249 | ||
1250 | if (rt) { | |
1251 | rt->u.dst.input = ort->u.dst.input; | |
1252 | rt->u.dst.output = ort->u.dst.output; | |
1253 | ||
1254 | memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32)); | |
1255 | rt->u.dst.dev = ort->u.dst.dev; | |
1256 | if (rt->u.dst.dev) | |
1257 | dev_hold(rt->u.dst.dev); | |
1258 | rt->rt6i_idev = ort->rt6i_idev; | |
1259 | if (rt->rt6i_idev) | |
1260 | in6_dev_hold(rt->rt6i_idev); | |
1261 | rt->u.dst.lastuse = jiffies; | |
1262 | rt->rt6i_expires = 0; | |
1263 | ||
1264 | ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway); | |
1265 | rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; | |
1266 | rt->rt6i_metric = 0; | |
1267 | ||
1268 | memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); | |
1269 | #ifdef CONFIG_IPV6_SUBTREES | |
1270 | memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); | |
1271 | #endif | |
1272 | } | |
1273 | return rt; | |
1274 | } | |
1275 | ||
1276 | struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev) | |
1277 | { | |
1278 | struct rt6_info *rt; | |
1279 | struct fib6_node *fn; | |
1280 | ||
1281 | fn = &ip6_routing_table; | |
1282 | ||
1283 | write_lock_bh(&rt6_lock); | |
1284 | for (rt = fn->leaf; rt; rt=rt->u.next) { | |
1285 | if (dev == rt->rt6i_dev && | |
1286 | ipv6_addr_equal(&rt->rt6i_gateway, addr)) | |
1287 | break; | |
1288 | } | |
1289 | if (rt) | |
1290 | dst_hold(&rt->u.dst); | |
1291 | write_unlock_bh(&rt6_lock); | |
1292 | return rt; | |
1293 | } | |
1294 | ||
1295 | struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr, | |
1296 | struct net_device *dev) | |
1297 | { | |
1298 | struct in6_rtmsg rtmsg; | |
1299 | ||
1300 | memset(&rtmsg, 0, sizeof(struct in6_rtmsg)); | |
1301 | rtmsg.rtmsg_type = RTMSG_NEWROUTE; | |
1302 | ipv6_addr_copy(&rtmsg.rtmsg_gateway, gwaddr); | |
1303 | rtmsg.rtmsg_metric = 1024; | |
1304 | rtmsg.rtmsg_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT | RTF_UP | RTF_EXPIRES; | |
1305 | ||
1306 | rtmsg.rtmsg_ifindex = dev->ifindex; | |
1307 | ||
1308 | ip6_route_add(&rtmsg, NULL, NULL); | |
1309 | return rt6_get_dflt_router(gwaddr, dev); | |
1310 | } | |
1311 | ||
1312 | void rt6_purge_dflt_routers(void) | |
1313 | { | |
1314 | struct rt6_info *rt; | |
1315 | ||
1316 | restart: | |
1317 | read_lock_bh(&rt6_lock); | |
1318 | for (rt = ip6_routing_table.leaf; rt; rt = rt->u.next) { | |
1319 | if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) { | |
1320 | dst_hold(&rt->u.dst); | |
1321 | ||
1322 | rt6_reset_dflt_pointer(NULL); | |
1323 | ||
1324 | read_unlock_bh(&rt6_lock); | |
1325 | ||
1326 | ip6_del_rt(rt, NULL, NULL); | |
1327 | ||
1328 | goto restart; | |
1329 | } | |
1330 | } | |
1331 | read_unlock_bh(&rt6_lock); | |
1332 | } | |
1333 | ||
1334 | int ipv6_route_ioctl(unsigned int cmd, void __user *arg) | |
1335 | { | |
1336 | struct in6_rtmsg rtmsg; | |
1337 | int err; | |
1338 | ||
1339 | switch(cmd) { | |
1340 | case SIOCADDRT: /* Add a route */ | |
1341 | case SIOCDELRT: /* Delete a route */ | |
1342 | if (!capable(CAP_NET_ADMIN)) | |
1343 | return -EPERM; | |
1344 | err = copy_from_user(&rtmsg, arg, | |
1345 | sizeof(struct in6_rtmsg)); | |
1346 | if (err) | |
1347 | return -EFAULT; | |
1348 | ||
1349 | rtnl_lock(); | |
1350 | switch (cmd) { | |
1351 | case SIOCADDRT: | |
1352 | err = ip6_route_add(&rtmsg, NULL, NULL); | |
1353 | break; | |
1354 | case SIOCDELRT: | |
1355 | err = ip6_route_del(&rtmsg, NULL, NULL); | |
1356 | break; | |
1357 | default: | |
1358 | err = -EINVAL; | |
1359 | } | |
1360 | rtnl_unlock(); | |
1361 | ||
1362 | return err; | |
1363 | }; | |
1364 | ||
1365 | return -EINVAL; | |
1366 | } | |
1367 | ||
1368 | /* | |
1369 | * Drop the packet on the floor | |
1370 | */ | |
1371 | ||
1372 | int ip6_pkt_discard(struct sk_buff *skb) | |
1373 | { | |
1374 | IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES); | |
1375 | icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_NOROUTE, 0, skb->dev); | |
1376 | kfree_skb(skb); | |
1377 | return 0; | |
1378 | } | |
1379 | ||
1380 | int ip6_pkt_discard_out(struct sk_buff *skb) | |
1381 | { | |
1382 | skb->dev = skb->dst->dev; | |
1383 | return ip6_pkt_discard(skb); | |
1384 | } | |
1385 | ||
1386 | /* | |
1387 | * Allocate a dst for local (unicast / anycast) address. | |
1388 | */ | |
1389 | ||
1390 | struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, | |
1391 | const struct in6_addr *addr, | |
1392 | int anycast) | |
1393 | { | |
1394 | struct rt6_info *rt = ip6_dst_alloc(); | |
1395 | ||
1396 | if (rt == NULL) | |
1397 | return ERR_PTR(-ENOMEM); | |
1398 | ||
1399 | dev_hold(&loopback_dev); | |
1400 | in6_dev_hold(idev); | |
1401 | ||
1402 | rt->u.dst.flags = DST_HOST; | |
1403 | rt->u.dst.input = ip6_input; | |
1404 | rt->u.dst.output = ip6_output; | |
1405 | rt->rt6i_dev = &loopback_dev; | |
1406 | rt->rt6i_idev = idev; | |
1407 | rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); | |
1408 | rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dst_mtu(&rt->u.dst)); | |
1409 | rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1; | |
1410 | rt->u.dst.obsolete = -1; | |
1411 | ||
1412 | rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP; | |
1413 | if (!anycast) | |
1414 | rt->rt6i_flags |= RTF_LOCAL; | |
1415 | rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway); | |
1416 | if (rt->rt6i_nexthop == NULL) { | |
1417 | dst_free((struct dst_entry *) rt); | |
1418 | return ERR_PTR(-ENOMEM); | |
1419 | } | |
1420 | ||
1421 | ipv6_addr_copy(&rt->rt6i_dst.addr, addr); | |
1422 | rt->rt6i_dst.plen = 128; | |
1423 | ||
1424 | atomic_set(&rt->u.dst.__refcnt, 1); | |
1425 | ||
1426 | return rt; | |
1427 | } | |
1428 | ||
1429 | static int fib6_ifdown(struct rt6_info *rt, void *arg) | |
1430 | { | |
1431 | if (((void*)rt->rt6i_dev == arg || arg == NULL) && | |
1432 | rt != &ip6_null_entry) { | |
1433 | RT6_TRACE("deleted by ifdown %p\n", rt); | |
1434 | return -1; | |
1435 | } | |
1436 | return 0; | |
1437 | } | |
1438 | ||
1439 | void rt6_ifdown(struct net_device *dev) | |
1440 | { | |
1441 | write_lock_bh(&rt6_lock); | |
1442 | fib6_clean_tree(&ip6_routing_table, fib6_ifdown, 0, dev); | |
1443 | write_unlock_bh(&rt6_lock); | |
1444 | } | |
1445 | ||
1446 | struct rt6_mtu_change_arg | |
1447 | { | |
1448 | struct net_device *dev; | |
1449 | unsigned mtu; | |
1450 | }; | |
1451 | ||
1452 | static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg) | |
1453 | { | |
1454 | struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg; | |
1455 | struct inet6_dev *idev; | |
1456 | ||
1457 | /* In IPv6 pmtu discovery is not optional, | |
1458 | so that RTAX_MTU lock cannot disable it. | |
1459 | We still use this lock to block changes | |
1460 | caused by addrconf/ndisc. | |
1461 | */ | |
1462 | ||
1463 | idev = __in6_dev_get(arg->dev); | |
1464 | if (idev == NULL) | |
1465 | return 0; | |
1466 | ||
1467 | /* For administrative MTU increase, there is no way to discover | |
1468 | IPv6 PMTU increase, so PMTU increase should be updated here. | |
1469 | Since RFC 1981 doesn't include administrative MTU increase | |
1470 | update PMTU increase is a MUST. (i.e. jumbo frame) | |
1471 | */ | |
1472 | /* | |
1473 | If new MTU is less than route PMTU, this new MTU will be the | |
1474 | lowest MTU in the path, update the route PMTU to reflect PMTU | |
1475 | decreases; if new MTU is greater than route PMTU, and the | |
1476 | old MTU is the lowest MTU in the path, update the route PMTU | |
1477 | to reflect the increase. In this case if the other nodes' MTU | |
1478 | also have the lowest MTU, TOO BIG MESSAGE will be lead to | |
1479 | PMTU discouvery. | |
1480 | */ | |
1481 | if (rt->rt6i_dev == arg->dev && | |
1482 | !dst_metric_locked(&rt->u.dst, RTAX_MTU) && | |
1483 | (dst_mtu(&rt->u.dst) > arg->mtu || | |
1484 | (dst_mtu(&rt->u.dst) < arg->mtu && | |
1485 | dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) | |
1486 | rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu; | |
1487 | rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(arg->mtu); | |
1488 | return 0; | |
1489 | } | |
1490 | ||
1491 | void rt6_mtu_change(struct net_device *dev, unsigned mtu) | |
1492 | { | |
1493 | struct rt6_mtu_change_arg arg; | |
1494 | ||
1495 | arg.dev = dev; | |
1496 | arg.mtu = mtu; | |
1497 | read_lock_bh(&rt6_lock); | |
1498 | fib6_clean_tree(&ip6_routing_table, rt6_mtu_change_route, 0, &arg); | |
1499 | read_unlock_bh(&rt6_lock); | |
1500 | } | |
1501 | ||
1502 | static int inet6_rtm_to_rtmsg(struct rtmsg *r, struct rtattr **rta, | |
1503 | struct in6_rtmsg *rtmsg) | |
1504 | { | |
1505 | memset(rtmsg, 0, sizeof(*rtmsg)); | |
1506 | ||
1507 | rtmsg->rtmsg_dst_len = r->rtm_dst_len; | |
1508 | rtmsg->rtmsg_src_len = r->rtm_src_len; | |
1509 | rtmsg->rtmsg_flags = RTF_UP; | |
1510 | if (r->rtm_type == RTN_UNREACHABLE) | |
1511 | rtmsg->rtmsg_flags |= RTF_REJECT; | |
1512 | ||
1513 | if (rta[RTA_GATEWAY-1]) { | |
1514 | if (rta[RTA_GATEWAY-1]->rta_len != RTA_LENGTH(16)) | |
1515 | return -EINVAL; | |
1516 | memcpy(&rtmsg->rtmsg_gateway, RTA_DATA(rta[RTA_GATEWAY-1]), 16); | |
1517 | rtmsg->rtmsg_flags |= RTF_GATEWAY; | |
1518 | } | |
1519 | if (rta[RTA_DST-1]) { | |
1520 | if (RTA_PAYLOAD(rta[RTA_DST-1]) < ((r->rtm_dst_len+7)>>3)) | |
1521 | return -EINVAL; | |
1522 | memcpy(&rtmsg->rtmsg_dst, RTA_DATA(rta[RTA_DST-1]), ((r->rtm_dst_len+7)>>3)); | |
1523 | } | |
1524 | if (rta[RTA_SRC-1]) { | |
1525 | if (RTA_PAYLOAD(rta[RTA_SRC-1]) < ((r->rtm_src_len+7)>>3)) | |
1526 | return -EINVAL; | |
1527 | memcpy(&rtmsg->rtmsg_src, RTA_DATA(rta[RTA_SRC-1]), ((r->rtm_src_len+7)>>3)); | |
1528 | } | |
1529 | if (rta[RTA_OIF-1]) { | |
1530 | if (rta[RTA_OIF-1]->rta_len != RTA_LENGTH(sizeof(int))) | |
1531 | return -EINVAL; | |
1532 | memcpy(&rtmsg->rtmsg_ifindex, RTA_DATA(rta[RTA_OIF-1]), sizeof(int)); | |
1533 | } | |
1534 | if (rta[RTA_PRIORITY-1]) { | |
1535 | if (rta[RTA_PRIORITY-1]->rta_len != RTA_LENGTH(4)) | |
1536 | return -EINVAL; | |
1537 | memcpy(&rtmsg->rtmsg_metric, RTA_DATA(rta[RTA_PRIORITY-1]), 4); | |
1538 | } | |
1539 | return 0; | |
1540 | } | |
1541 | ||
1542 | int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) | |
1543 | { | |
1544 | struct rtmsg *r = NLMSG_DATA(nlh); | |
1545 | struct in6_rtmsg rtmsg; | |
1546 | ||
1547 | if (inet6_rtm_to_rtmsg(r, arg, &rtmsg)) | |
1548 | return -EINVAL; | |
1549 | return ip6_route_del(&rtmsg, nlh, arg); | |
1550 | } | |
1551 | ||
1552 | int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) | |
1553 | { | |
1554 | struct rtmsg *r = NLMSG_DATA(nlh); | |
1555 | struct in6_rtmsg rtmsg; | |
1556 | ||
1557 | if (inet6_rtm_to_rtmsg(r, arg, &rtmsg)) | |
1558 | return -EINVAL; | |
1559 | return ip6_route_add(&rtmsg, nlh, arg); | |
1560 | } | |
1561 | ||
1562 | struct rt6_rtnl_dump_arg | |
1563 | { | |
1564 | struct sk_buff *skb; | |
1565 | struct netlink_callback *cb; | |
1566 | }; | |
1567 | ||
1568 | static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt, | |
1569 | struct in6_addr *dst, | |
1570 | struct in6_addr *src, | |
1571 | int iif, | |
1572 | int type, u32 pid, u32 seq, | |
b6544c0b JHS |
1573 | struct nlmsghdr *in_nlh, int prefix, |
1574 | unsigned int flags) | |
1da177e4 LT |
1575 | { |
1576 | struct rtmsg *rtm; | |
1577 | struct nlmsghdr *nlh; | |
1578 | unsigned char *b = skb->tail; | |
1579 | struct rta_cacheinfo ci; | |
1580 | ||
1581 | if (prefix) { /* user wants prefix routes only */ | |
1582 | if (!(rt->rt6i_flags & RTF_PREFIX_RT)) { | |
1583 | /* success since this is not a prefix route */ | |
1584 | return 1; | |
1585 | } | |
1586 | } | |
1587 | ||
1588 | if (!pid && in_nlh) { | |
1589 | pid = in_nlh->nlmsg_pid; | |
1590 | } | |
1591 | ||
b6544c0b | 1592 | nlh = NLMSG_NEW(skb, pid, seq, type, sizeof(*rtm), flags); |
1da177e4 LT |
1593 | rtm = NLMSG_DATA(nlh); |
1594 | rtm->rtm_family = AF_INET6; | |
1595 | rtm->rtm_dst_len = rt->rt6i_dst.plen; | |
1596 | rtm->rtm_src_len = rt->rt6i_src.plen; | |
1597 | rtm->rtm_tos = 0; | |
1598 | rtm->rtm_table = RT_TABLE_MAIN; | |
1599 | if (rt->rt6i_flags&RTF_REJECT) | |
1600 | rtm->rtm_type = RTN_UNREACHABLE; | |
1601 | else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK)) | |
1602 | rtm->rtm_type = RTN_LOCAL; | |
1603 | else | |
1604 | rtm->rtm_type = RTN_UNICAST; | |
1605 | rtm->rtm_flags = 0; | |
1606 | rtm->rtm_scope = RT_SCOPE_UNIVERSE; | |
1607 | rtm->rtm_protocol = rt->rt6i_protocol; | |
1608 | if (rt->rt6i_flags&RTF_DYNAMIC) | |
1609 | rtm->rtm_protocol = RTPROT_REDIRECT; | |
1610 | else if (rt->rt6i_flags & RTF_ADDRCONF) | |
1611 | rtm->rtm_protocol = RTPROT_KERNEL; | |
1612 | else if (rt->rt6i_flags&RTF_DEFAULT) | |
1613 | rtm->rtm_protocol = RTPROT_RA; | |
1614 | ||
1615 | if (rt->rt6i_flags&RTF_CACHE) | |
1616 | rtm->rtm_flags |= RTM_F_CLONED; | |
1617 | ||
1618 | if (dst) { | |
1619 | RTA_PUT(skb, RTA_DST, 16, dst); | |
1620 | rtm->rtm_dst_len = 128; | |
1621 | } else if (rtm->rtm_dst_len) | |
1622 | RTA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr); | |
1623 | #ifdef CONFIG_IPV6_SUBTREES | |
1624 | if (src) { | |
1625 | RTA_PUT(skb, RTA_SRC, 16, src); | |
1626 | rtm->rtm_src_len = 128; | |
1627 | } else if (rtm->rtm_src_len) | |
1628 | RTA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr); | |
1629 | #endif | |
1630 | if (iif) | |
1631 | RTA_PUT(skb, RTA_IIF, 4, &iif); | |
1632 | else if (dst) { | |
1633 | struct in6_addr saddr_buf; | |
1634 | if (ipv6_get_saddr(&rt->u.dst, dst, &saddr_buf) == 0) | |
1635 | RTA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf); | |
1636 | } | |
1637 | if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0) | |
1638 | goto rtattr_failure; | |
1639 | if (rt->u.dst.neighbour) | |
1640 | RTA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key); | |
1641 | if (rt->u.dst.dev) | |
1642 | RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->rt6i_dev->ifindex); | |
1643 | RTA_PUT(skb, RTA_PRIORITY, 4, &rt->rt6i_metric); | |
1644 | ci.rta_lastuse = jiffies_to_clock_t(jiffies - rt->u.dst.lastuse); | |
1645 | if (rt->rt6i_expires) | |
1646 | ci.rta_expires = jiffies_to_clock_t(rt->rt6i_expires - jiffies); | |
1647 | else | |
1648 | ci.rta_expires = 0; | |
1649 | ci.rta_used = rt->u.dst.__use; | |
1650 | ci.rta_clntref = atomic_read(&rt->u.dst.__refcnt); | |
1651 | ci.rta_error = rt->u.dst.error; | |
1652 | ci.rta_id = 0; | |
1653 | ci.rta_ts = 0; | |
1654 | ci.rta_tsage = 0; | |
1655 | RTA_PUT(skb, RTA_CACHEINFO, sizeof(ci), &ci); | |
1656 | nlh->nlmsg_len = skb->tail - b; | |
1657 | return skb->len; | |
1658 | ||
1659 | nlmsg_failure: | |
1660 | rtattr_failure: | |
1661 | skb_trim(skb, b - skb->data); | |
1662 | return -1; | |
1663 | } | |
1664 | ||
1665 | static int rt6_dump_route(struct rt6_info *rt, void *p_arg) | |
1666 | { | |
1667 | struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg; | |
1668 | int prefix; | |
1669 | ||
1670 | if (arg->cb->nlh->nlmsg_len >= NLMSG_LENGTH(sizeof(struct rtmsg))) { | |
1671 | struct rtmsg *rtm = NLMSG_DATA(arg->cb->nlh); | |
1672 | prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0; | |
1673 | } else | |
1674 | prefix = 0; | |
1675 | ||
1676 | return rt6_fill_node(arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE, | |
1677 | NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq, | |
b6544c0b | 1678 | NULL, prefix, NLM_F_MULTI); |
1da177e4 LT |
1679 | } |
1680 | ||
1681 | static int fib6_dump_node(struct fib6_walker_t *w) | |
1682 | { | |
1683 | int res; | |
1684 | struct rt6_info *rt; | |
1685 | ||
1686 | for (rt = w->leaf; rt; rt = rt->u.next) { | |
1687 | res = rt6_dump_route(rt, w->args); | |
1688 | if (res < 0) { | |
1689 | /* Frame is full, suspend walking */ | |
1690 | w->leaf = rt; | |
1691 | return 1; | |
1692 | } | |
1693 | BUG_TRAP(res!=0); | |
1694 | } | |
1695 | w->leaf = NULL; | |
1696 | return 0; | |
1697 | } | |
1698 | ||
1699 | static void fib6_dump_end(struct netlink_callback *cb) | |
1700 | { | |
1701 | struct fib6_walker_t *w = (void*)cb->args[0]; | |
1702 | ||
1703 | if (w) { | |
1704 | cb->args[0] = 0; | |
1705 | fib6_walker_unlink(w); | |
1706 | kfree(w); | |
1707 | } | |
1708 | if (cb->args[1]) { | |
1709 | cb->done = (void*)cb->args[1]; | |
1710 | cb->args[1] = 0; | |
1711 | } | |
1712 | } | |
1713 | ||
1714 | static int fib6_dump_done(struct netlink_callback *cb) | |
1715 | { | |
1716 | fib6_dump_end(cb); | |
1717 | return cb->done(cb); | |
1718 | } | |
1719 | ||
1720 | int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) | |
1721 | { | |
1722 | struct rt6_rtnl_dump_arg arg; | |
1723 | struct fib6_walker_t *w; | |
1724 | int res; | |
1725 | ||
1726 | arg.skb = skb; | |
1727 | arg.cb = cb; | |
1728 | ||
1729 | w = (void*)cb->args[0]; | |
1730 | if (w == NULL) { | |
1731 | /* New dump: | |
1732 | * | |
1733 | * 1. hook callback destructor. | |
1734 | */ | |
1735 | cb->args[1] = (long)cb->done; | |
1736 | cb->done = fib6_dump_done; | |
1737 | ||
1738 | /* | |
1739 | * 2. allocate and initialize walker. | |
1740 | */ | |
1741 | w = kmalloc(sizeof(*w), GFP_ATOMIC); | |
1742 | if (w == NULL) | |
1743 | return -ENOMEM; | |
1744 | RT6_TRACE("dump<%p", w); | |
1745 | memset(w, 0, sizeof(*w)); | |
1746 | w->root = &ip6_routing_table; | |
1747 | w->func = fib6_dump_node; | |
1748 | w->args = &arg; | |
1749 | cb->args[0] = (long)w; | |
1750 | read_lock_bh(&rt6_lock); | |
1751 | res = fib6_walk(w); | |
1752 | read_unlock_bh(&rt6_lock); | |
1753 | } else { | |
1754 | w->args = &arg; | |
1755 | read_lock_bh(&rt6_lock); | |
1756 | res = fib6_walk_continue(w); | |
1757 | read_unlock_bh(&rt6_lock); | |
1758 | } | |
1759 | #if RT6_DEBUG >= 3 | |
1760 | if (res <= 0 && skb->len == 0) | |
1761 | RT6_TRACE("%p>dump end\n", w); | |
1762 | #endif | |
1763 | res = res < 0 ? res : skb->len; | |
1764 | /* res < 0 is an error. (really, impossible) | |
1765 | res == 0 means that dump is complete, but skb still can contain data. | |
1766 | res > 0 dump is not complete, but frame is full. | |
1767 | */ | |
1768 | /* Destroy walker, if dump of this table is complete. */ | |
1769 | if (res <= 0) | |
1770 | fib6_dump_end(cb); | |
1771 | return res; | |
1772 | } | |
1773 | ||
1774 | int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg) | |
1775 | { | |
1776 | struct rtattr **rta = arg; | |
1777 | int iif = 0; | |
1778 | int err = -ENOBUFS; | |
1779 | struct sk_buff *skb; | |
1780 | struct flowi fl; | |
1781 | struct rt6_info *rt; | |
1782 | ||
1783 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); | |
1784 | if (skb == NULL) | |
1785 | goto out; | |
1786 | ||
1787 | /* Reserve room for dummy headers, this skb can pass | |
1788 | through good chunk of routing engine. | |
1789 | */ | |
1790 | skb->mac.raw = skb->data; | |
1791 | skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr)); | |
1792 | ||
1793 | memset(&fl, 0, sizeof(fl)); | |
1794 | if (rta[RTA_SRC-1]) | |
1795 | ipv6_addr_copy(&fl.fl6_src, | |
1796 | (struct in6_addr*)RTA_DATA(rta[RTA_SRC-1])); | |
1797 | if (rta[RTA_DST-1]) | |
1798 | ipv6_addr_copy(&fl.fl6_dst, | |
1799 | (struct in6_addr*)RTA_DATA(rta[RTA_DST-1])); | |
1800 | ||
1801 | if (rta[RTA_IIF-1]) | |
1802 | memcpy(&iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int)); | |
1803 | ||
1804 | if (iif) { | |
1805 | struct net_device *dev; | |
1806 | dev = __dev_get_by_index(iif); | |
1807 | if (!dev) { | |
1808 | err = -ENODEV; | |
1809 | goto out_free; | |
1810 | } | |
1811 | } | |
1812 | ||
1813 | fl.oif = 0; | |
1814 | if (rta[RTA_OIF-1]) | |
1815 | memcpy(&fl.oif, RTA_DATA(rta[RTA_OIF-1]), sizeof(int)); | |
1816 | ||
1817 | rt = (struct rt6_info*)ip6_route_output(NULL, &fl); | |
1818 | ||
1819 | skb->dst = &rt->u.dst; | |
1820 | ||
1821 | NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid; | |
1822 | err = rt6_fill_node(skb, rt, | |
1823 | &fl.fl6_dst, &fl.fl6_src, | |
1824 | iif, | |
1825 | RTM_NEWROUTE, NETLINK_CB(in_skb).pid, | |
b6544c0b | 1826 | nlh->nlmsg_seq, nlh, 0, 0); |
1da177e4 LT |
1827 | if (err < 0) { |
1828 | err = -EMSGSIZE; | |
1829 | goto out_free; | |
1830 | } | |
1831 | ||
1832 | err = netlink_unicast(rtnl, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT); | |
1833 | if (err > 0) | |
1834 | err = 0; | |
1835 | out: | |
1836 | return err; | |
1837 | out_free: | |
1838 | kfree_skb(skb); | |
1839 | goto out; | |
1840 | } | |
1841 | ||
1842 | void inet6_rt_notify(int event, struct rt6_info *rt, struct nlmsghdr *nlh) | |
1843 | { | |
1844 | struct sk_buff *skb; | |
1845 | int size = NLMSG_SPACE(sizeof(struct rtmsg)+256); | |
1846 | ||
1847 | skb = alloc_skb(size, gfp_any()); | |
1848 | if (!skb) { | |
1849 | netlink_set_err(rtnl, 0, RTMGRP_IPV6_ROUTE, ENOBUFS); | |
1850 | return; | |
1851 | } | |
b6544c0b | 1852 | if (rt6_fill_node(skb, rt, NULL, NULL, 0, event, 0, 0, nlh, 0, 0) < 0) { |
1da177e4 LT |
1853 | kfree_skb(skb); |
1854 | netlink_set_err(rtnl, 0, RTMGRP_IPV6_ROUTE, EINVAL); | |
1855 | return; | |
1856 | } | |
1857 | NETLINK_CB(skb).dst_groups = RTMGRP_IPV6_ROUTE; | |
1858 | netlink_broadcast(rtnl, skb, 0, RTMGRP_IPV6_ROUTE, gfp_any()); | |
1859 | } | |
1860 | ||
1861 | /* | |
1862 | * /proc | |
1863 | */ | |
1864 | ||
1865 | #ifdef CONFIG_PROC_FS | |
1866 | ||
1867 | #define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1) | |
1868 | ||
1869 | struct rt6_proc_arg | |
1870 | { | |
1871 | char *buffer; | |
1872 | int offset; | |
1873 | int length; | |
1874 | int skip; | |
1875 | int len; | |
1876 | }; | |
1877 | ||
1878 | static int rt6_info_route(struct rt6_info *rt, void *p_arg) | |
1879 | { | |
1880 | struct rt6_proc_arg *arg = (struct rt6_proc_arg *) p_arg; | |
1881 | int i; | |
1882 | ||
1883 | if (arg->skip < arg->offset / RT6_INFO_LEN) { | |
1884 | arg->skip++; | |
1885 | return 0; | |
1886 | } | |
1887 | ||
1888 | if (arg->len >= arg->length) | |
1889 | return 0; | |
1890 | ||
1891 | for (i=0; i<16; i++) { | |
1892 | sprintf(arg->buffer + arg->len, "%02x", | |
1893 | rt->rt6i_dst.addr.s6_addr[i]); | |
1894 | arg->len += 2; | |
1895 | } | |
1896 | arg->len += sprintf(arg->buffer + arg->len, " %02x ", | |
1897 | rt->rt6i_dst.plen); | |
1898 | ||
1899 | #ifdef CONFIG_IPV6_SUBTREES | |
1900 | for (i=0; i<16; i++) { | |
1901 | sprintf(arg->buffer + arg->len, "%02x", | |
1902 | rt->rt6i_src.addr.s6_addr[i]); | |
1903 | arg->len += 2; | |
1904 | } | |
1905 | arg->len += sprintf(arg->buffer + arg->len, " %02x ", | |
1906 | rt->rt6i_src.plen); | |
1907 | #else | |
1908 | sprintf(arg->buffer + arg->len, | |
1909 | "00000000000000000000000000000000 00 "); | |
1910 | arg->len += 36; | |
1911 | #endif | |
1912 | ||
1913 | if (rt->rt6i_nexthop) { | |
1914 | for (i=0; i<16; i++) { | |
1915 | sprintf(arg->buffer + arg->len, "%02x", | |
1916 | rt->rt6i_nexthop->primary_key[i]); | |
1917 | arg->len += 2; | |
1918 | } | |
1919 | } else { | |
1920 | sprintf(arg->buffer + arg->len, | |
1921 | "00000000000000000000000000000000"); | |
1922 | arg->len += 32; | |
1923 | } | |
1924 | arg->len += sprintf(arg->buffer + arg->len, | |
1925 | " %08x %08x %08x %08x %8s\n", | |
1926 | rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), | |
1927 | rt->u.dst.__use, rt->rt6i_flags, | |
1928 | rt->rt6i_dev ? rt->rt6i_dev->name : ""); | |
1929 | return 0; | |
1930 | } | |
1931 | ||
1932 | static int rt6_proc_info(char *buffer, char **start, off_t offset, int length) | |
1933 | { | |
1934 | struct rt6_proc_arg arg; | |
1935 | arg.buffer = buffer; | |
1936 | arg.offset = offset; | |
1937 | arg.length = length; | |
1938 | arg.skip = 0; | |
1939 | arg.len = 0; | |
1940 | ||
1941 | read_lock_bh(&rt6_lock); | |
1942 | fib6_clean_tree(&ip6_routing_table, rt6_info_route, 0, &arg); | |
1943 | read_unlock_bh(&rt6_lock); | |
1944 | ||
1945 | *start = buffer; | |
1946 | if (offset) | |
1947 | *start += offset % RT6_INFO_LEN; | |
1948 | ||
1949 | arg.len -= offset % RT6_INFO_LEN; | |
1950 | ||
1951 | if (arg.len > length) | |
1952 | arg.len = length; | |
1953 | if (arg.len < 0) | |
1954 | arg.len = 0; | |
1955 | ||
1956 | return arg.len; | |
1957 | } | |
1958 | ||
1959 | extern struct rt6_statistics rt6_stats; | |
1960 | ||
1961 | static int rt6_stats_seq_show(struct seq_file *seq, void *v) | |
1962 | { | |
1963 | seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n", | |
1964 | rt6_stats.fib_nodes, rt6_stats.fib_route_nodes, | |
1965 | rt6_stats.fib_rt_alloc, rt6_stats.fib_rt_entries, | |
1966 | rt6_stats.fib_rt_cache, | |
1967 | atomic_read(&ip6_dst_ops.entries), | |
1968 | rt6_stats.fib_discarded_routes); | |
1969 | ||
1970 | return 0; | |
1971 | } | |
1972 | ||
1973 | static int rt6_stats_seq_open(struct inode *inode, struct file *file) | |
1974 | { | |
1975 | return single_open(file, rt6_stats_seq_show, NULL); | |
1976 | } | |
1977 | ||
1978 | static struct file_operations rt6_stats_seq_fops = { | |
1979 | .owner = THIS_MODULE, | |
1980 | .open = rt6_stats_seq_open, | |
1981 | .read = seq_read, | |
1982 | .llseek = seq_lseek, | |
1983 | .release = single_release, | |
1984 | }; | |
1985 | #endif /* CONFIG_PROC_FS */ | |
1986 | ||
1987 | #ifdef CONFIG_SYSCTL | |
1988 | ||
1989 | static int flush_delay; | |
1990 | ||
1991 | static | |
1992 | int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp, | |
1993 | void __user *buffer, size_t *lenp, loff_t *ppos) | |
1994 | { | |
1995 | if (write) { | |
1996 | proc_dointvec(ctl, write, filp, buffer, lenp, ppos); | |
1997 | fib6_run_gc(flush_delay <= 0 ? ~0UL : (unsigned long)flush_delay); | |
1998 | return 0; | |
1999 | } else | |
2000 | return -EINVAL; | |
2001 | } | |
2002 | ||
2003 | ctl_table ipv6_route_table[] = { | |
2004 | { | |
2005 | .ctl_name = NET_IPV6_ROUTE_FLUSH, | |
2006 | .procname = "flush", | |
2007 | .data = &flush_delay, | |
2008 | .maxlen = sizeof(int), | |
89c8b3a1 | 2009 | .mode = 0200, |
1da177e4 LT |
2010 | .proc_handler = &ipv6_sysctl_rtcache_flush |
2011 | }, | |
2012 | { | |
2013 | .ctl_name = NET_IPV6_ROUTE_GC_THRESH, | |
2014 | .procname = "gc_thresh", | |
2015 | .data = &ip6_dst_ops.gc_thresh, | |
2016 | .maxlen = sizeof(int), | |
2017 | .mode = 0644, | |
2018 | .proc_handler = &proc_dointvec, | |
2019 | }, | |
2020 | { | |
2021 | .ctl_name = NET_IPV6_ROUTE_MAX_SIZE, | |
2022 | .procname = "max_size", | |
2023 | .data = &ip6_rt_max_size, | |
2024 | .maxlen = sizeof(int), | |
2025 | .mode = 0644, | |
2026 | .proc_handler = &proc_dointvec, | |
2027 | }, | |
2028 | { | |
2029 | .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL, | |
2030 | .procname = "gc_min_interval", | |
2031 | .data = &ip6_rt_gc_min_interval, | |
2032 | .maxlen = sizeof(int), | |
2033 | .mode = 0644, | |
2034 | .proc_handler = &proc_dointvec_jiffies, | |
2035 | .strategy = &sysctl_jiffies, | |
2036 | }, | |
2037 | { | |
2038 | .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT, | |
2039 | .procname = "gc_timeout", | |
2040 | .data = &ip6_rt_gc_timeout, | |
2041 | .maxlen = sizeof(int), | |
2042 | .mode = 0644, | |
2043 | .proc_handler = &proc_dointvec_jiffies, | |
2044 | .strategy = &sysctl_jiffies, | |
2045 | }, | |
2046 | { | |
2047 | .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL, | |
2048 | .procname = "gc_interval", | |
2049 | .data = &ip6_rt_gc_interval, | |
2050 | .maxlen = sizeof(int), | |
2051 | .mode = 0644, | |
2052 | .proc_handler = &proc_dointvec_jiffies, | |
2053 | .strategy = &sysctl_jiffies, | |
2054 | }, | |
2055 | { | |
2056 | .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY, | |
2057 | .procname = "gc_elasticity", | |
2058 | .data = &ip6_rt_gc_elasticity, | |
2059 | .maxlen = sizeof(int), | |
2060 | .mode = 0644, | |
2061 | .proc_handler = &proc_dointvec_jiffies, | |
2062 | .strategy = &sysctl_jiffies, | |
2063 | }, | |
2064 | { | |
2065 | .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES, | |
2066 | .procname = "mtu_expires", | |
2067 | .data = &ip6_rt_mtu_expires, | |
2068 | .maxlen = sizeof(int), | |
2069 | .mode = 0644, | |
2070 | .proc_handler = &proc_dointvec_jiffies, | |
2071 | .strategy = &sysctl_jiffies, | |
2072 | }, | |
2073 | { | |
2074 | .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS, | |
2075 | .procname = "min_adv_mss", | |
2076 | .data = &ip6_rt_min_advmss, | |
2077 | .maxlen = sizeof(int), | |
2078 | .mode = 0644, | |
2079 | .proc_handler = &proc_dointvec_jiffies, | |
2080 | .strategy = &sysctl_jiffies, | |
2081 | }, | |
2082 | { | |
2083 | .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS, | |
2084 | .procname = "gc_min_interval_ms", | |
2085 | .data = &ip6_rt_gc_min_interval, | |
2086 | .maxlen = sizeof(int), | |
2087 | .mode = 0644, | |
2088 | .proc_handler = &proc_dointvec_ms_jiffies, | |
2089 | .strategy = &sysctl_ms_jiffies, | |
2090 | }, | |
2091 | { .ctl_name = 0 } | |
2092 | }; | |
2093 | ||
2094 | #endif | |
2095 | ||
2096 | void __init ip6_route_init(void) | |
2097 | { | |
2098 | struct proc_dir_entry *p; | |
2099 | ||
2100 | ip6_dst_ops.kmem_cachep = kmem_cache_create("ip6_dst_cache", | |
2101 | sizeof(struct rt6_info), | |
2102 | 0, SLAB_HWCACHE_ALIGN, | |
2103 | NULL, NULL); | |
2104 | if (!ip6_dst_ops.kmem_cachep) | |
2105 | panic("cannot create ip6_dst_cache"); | |
2106 | ||
2107 | fib6_init(); | |
2108 | #ifdef CONFIG_PROC_FS | |
2109 | p = proc_net_create("ipv6_route", 0, rt6_proc_info); | |
2110 | if (p) | |
2111 | p->owner = THIS_MODULE; | |
2112 | ||
2113 | proc_net_fops_create("rt6_stats", S_IRUGO, &rt6_stats_seq_fops); | |
2114 | #endif | |
2115 | #ifdef CONFIG_XFRM | |
2116 | xfrm6_init(); | |
2117 | #endif | |
2118 | } | |
2119 | ||
2120 | void ip6_route_cleanup(void) | |
2121 | { | |
2122 | #ifdef CONFIG_PROC_FS | |
2123 | proc_net_remove("ipv6_route"); | |
2124 | proc_net_remove("rt6_stats"); | |
2125 | #endif | |
2126 | #ifdef CONFIG_XFRM | |
2127 | xfrm6_fini(); | |
2128 | #endif | |
2129 | rt6_ifdown(NULL); | |
2130 | fib6_gc_cleanup(); | |
2131 | kmem_cache_destroy(ip6_dst_ops.kmem_cachep); | |
2132 | } |