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[IPV6]: ADDRCONF: Add accept_ra_pinfo sysctl.
[linux-2.6/linux-2.6-openrd.git] / net / ipv6 / ndisc.c
blob3b56be85234ef160b50aee7e347abe5ec3d16fba
1 /*
2 * Neighbour Discovery for IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Mike Shaver <shaver@ingenia.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15 /*
16 * Changes:
17 *
18 * Lars Fenneberg : fixed MTU setting on receipt
19 * of an RA.
20 *
21 * Janos Farkas : kmalloc failure checks
22 * Alexey Kuznetsov : state machine reworked
23 * and moved to net/core.
24 * Pekka Savola : RFC2461 validation
25 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
26 */
27
28 /* Set to 3 to get tracing... */
29 #define ND_DEBUG 1
30
31 #define ND_PRINTK(fmt, args...) do { if (net_ratelimit()) { printk(fmt, ## args); } } while(0)
32 #define ND_NOPRINTK(x...) do { ; } while(0)
33 #define ND_PRINTK0 ND_PRINTK
34 #define ND_PRINTK1 ND_NOPRINTK
35 #define ND_PRINTK2 ND_NOPRINTK
36 #define ND_PRINTK3 ND_NOPRINTK
37 #if ND_DEBUG >= 1
38 #undef ND_PRINTK1
39 #define ND_PRINTK1 ND_PRINTK
40 #endif
41 #if ND_DEBUG >= 2
42 #undef ND_PRINTK2
43 #define ND_PRINTK2 ND_PRINTK
44 #endif
45 #if ND_DEBUG >= 3
46 #undef ND_PRINTK3
47 #define ND_PRINTK3 ND_PRINTK
48 #endif
49
50 #include <linux/module.h>
51 #include <linux/config.h>
52 #include <linux/errno.h>
53 #include <linux/types.h>
54 #include <linux/socket.h>
55 #include <linux/sockios.h>
56 #include <linux/sched.h>
57 #include <linux/net.h>
58 #include <linux/in6.h>
59 #include <linux/route.h>
60 #include <linux/init.h>
61 #include <linux/rcupdate.h>
62 #ifdef CONFIG_SYSCTL
63 #include <linux/sysctl.h>
64 #endif
65
66 #include <linux/if_arp.h>
67 #include <linux/ipv6.h>
68 #include <linux/icmpv6.h>
69 #include <linux/jhash.h>
70
71 #include <net/sock.h>
72 #include <net/snmp.h>
73
74 #include <net/ipv6.h>
75 #include <net/protocol.h>
76 #include <net/ndisc.h>
77 #include <net/ip6_route.h>
78 #include <net/addrconf.h>
79 #include <net/icmp.h>
80
81 #include <net/flow.h>
82 #include <net/ip6_checksum.h>
83 #include <linux/proc_fs.h>
84
85 #include <linux/netfilter.h>
86 #include <linux/netfilter_ipv6.h>
87
88 static struct socket *ndisc_socket;
89
90 static u32 ndisc_hash(const void *pkey, const struct net_device *dev);
91 static int ndisc_constructor(struct neighbour *neigh);
92 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
93 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
94 static int pndisc_constructor(struct pneigh_entry *n);
95 static void pndisc_destructor(struct pneigh_entry *n);
96 static void pndisc_redo(struct sk_buff *skb);
97
98 static struct neigh_ops ndisc_generic_ops = {
99 .family = AF_INET6,
100 .solicit = ndisc_solicit,
101 .error_report = ndisc_error_report,
102 .output = neigh_resolve_output,
103 .connected_output = neigh_connected_output,
104 .hh_output = dev_queue_xmit,
105 .queue_xmit = dev_queue_xmit,
106 };
107
108 static struct neigh_ops ndisc_hh_ops = {
109 .family = AF_INET6,
110 .solicit = ndisc_solicit,
111 .error_report = ndisc_error_report,
112 .output = neigh_resolve_output,
113 .connected_output = neigh_resolve_output,
114 .hh_output = dev_queue_xmit,
115 .queue_xmit = dev_queue_xmit,
116 };
117
118
119 static struct neigh_ops ndisc_direct_ops = {
120 .family = AF_INET6,
121 .output = dev_queue_xmit,
122 .connected_output = dev_queue_xmit,
123 .hh_output = dev_queue_xmit,
124 .queue_xmit = dev_queue_xmit,
125 };
126
127 struct neigh_table nd_tbl = {
128 .family = AF_INET6,
129 .entry_size = sizeof(struct neighbour) + sizeof(struct in6_addr),
130 .key_len = sizeof(struct in6_addr),
131 .hash = ndisc_hash,
132 .constructor = ndisc_constructor,
133 .pconstructor = pndisc_constructor,
134 .pdestructor = pndisc_destructor,
135 .proxy_redo = pndisc_redo,
136 .id = "ndisc_cache",
137 .parms = {
138 .tbl = &nd_tbl,
139 .base_reachable_time = 30 * HZ,
140 .retrans_time = 1 * HZ,
141 .gc_staletime = 60 * HZ,
142 .reachable_time = 30 * HZ,
143 .delay_probe_time = 5 * HZ,
144 .queue_len = 3,
145 .ucast_probes = 3,
146 .mcast_probes = 3,
147 .anycast_delay = 1 * HZ,
148 .proxy_delay = (8 * HZ) / 10,
149 .proxy_qlen = 64,
150 },
151 .gc_interval = 30 * HZ,
152 .gc_thresh1 = 128,
153 .gc_thresh2 = 512,
154 .gc_thresh3 = 1024,
155 };
156
157 /* ND options */
158 struct ndisc_options {
159 struct nd_opt_hdr *nd_opt_array[__ND_OPT_MAX];
160 };
161
162 #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
163 #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
164 #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
165 #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
166 #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
167 #define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
168
169 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
170
171 /*
172 * Return the padding between the option length and the start of the
173 * link addr. Currently only IP-over-InfiniBand needs this, although
174 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
175 * also need a pad of 2.
176 */
177 static int ndisc_addr_option_pad(unsigned short type)
178 {
179 switch (type) {
180 case ARPHRD_INFINIBAND: return 2;
181 default: return 0;
182 }
183 }
184
185 static inline int ndisc_opt_addr_space(struct net_device *dev)
186 {
187 return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type));
188 }
189
190 static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len,
191 unsigned short addr_type)
192 {
193 int space = NDISC_OPT_SPACE(data_len);
194 int pad = ndisc_addr_option_pad(addr_type);
195
196 opt[0] = type;
197 opt[1] = space>>3;
198
199 memset(opt + 2, 0, pad);
200 opt += pad;
201 space -= pad;
202
203 memcpy(opt+2, data, data_len);
204 data_len += 2;
205 opt += data_len;
206 if ((space -= data_len) > 0)
207 memset(opt, 0, space);
208 return opt + space;
209 }
210
211 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
212 struct nd_opt_hdr *end)
213 {
214 int type;
215 if (!cur || !end || cur >= end)
216 return NULL;
217 type = cur->nd_opt_type;
218 do {
219 cur = ((void *)cur) + (cur->nd_opt_len << 3);
220 } while(cur < end && cur->nd_opt_type != type);
221 return (cur <= end && cur->nd_opt_type == type ? cur : NULL);
222 }
223
224 static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
225 struct ndisc_options *ndopts)
226 {
227 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
228
229 if (!nd_opt || opt_len < 0 || !ndopts)
230 return NULL;
231 memset(ndopts, 0, sizeof(*ndopts));
232 while (opt_len) {
233 int l;
234 if (opt_len < sizeof(struct nd_opt_hdr))
235 return NULL;
236 l = nd_opt->nd_opt_len << 3;
237 if (opt_len < l || l == 0)
238 return NULL;
239 switch (nd_opt->nd_opt_type) {
240 case ND_OPT_SOURCE_LL_ADDR:
241 case ND_OPT_TARGET_LL_ADDR:
242 case ND_OPT_MTU:
243 case ND_OPT_REDIRECT_HDR:
244 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
245 ND_PRINTK2(KERN_WARNING
246 "%s(): duplicated ND6 option found: type=%d\n",
247 __FUNCTION__,
248 nd_opt->nd_opt_type);
249 } else {
250 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
251 }
252 break;
253 case ND_OPT_PREFIX_INFO:
254 ndopts->nd_opts_pi_end = nd_opt;
255 if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0)
256 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
257 break;
258 default:
259 /*
260 * Unknown options must be silently ignored,
261 * to accommodate future extension to the protocol.
262 */
263 ND_PRINTK2(KERN_NOTICE
264 "%s(): ignored unsupported option; type=%d, len=%d\n",
265 __FUNCTION__,
266 nd_opt->nd_opt_type, nd_opt->nd_opt_len);
267 }
268 opt_len -= l;
269 nd_opt = ((void *)nd_opt) + l;
270 }
271 return ndopts;
272 }
273
274 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
275 struct net_device *dev)
276 {
277 u8 *lladdr = (u8 *)(p + 1);
278 int lladdrlen = p->nd_opt_len << 3;
279 int prepad = ndisc_addr_option_pad(dev->type);
280 if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
281 return NULL;
282 return (lladdr + prepad);
283 }
284
285 int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
286 {
287 switch (dev->type) {
288 case ARPHRD_ETHER:
289 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
290 case ARPHRD_FDDI:
291 ipv6_eth_mc_map(addr, buf);
292 return 0;
293 case ARPHRD_IEEE802_TR:
294 ipv6_tr_mc_map(addr,buf);
295 return 0;
296 case ARPHRD_ARCNET:
297 ipv6_arcnet_mc_map(addr, buf);
298 return 0;
299 case ARPHRD_INFINIBAND:
300 ipv6_ib_mc_map(addr, buf);
301 return 0;
302 default:
303 if (dir) {
304 memcpy(buf, dev->broadcast, dev->addr_len);
305 return 0;
306 }
307 }
308 return -EINVAL;
309 }
310
311 static u32 ndisc_hash(const void *pkey, const struct net_device *dev)
312 {
313 const u32 *p32 = pkey;
314 u32 addr_hash, i;
315
316 addr_hash = 0;
317 for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++)
318 addr_hash ^= *p32++;
319
320 return jhash_2words(addr_hash, dev->ifindex, nd_tbl.hash_rnd);
321 }
322
323 static int ndisc_constructor(struct neighbour *neigh)
324 {
325 struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
326 struct net_device *dev = neigh->dev;
327 struct inet6_dev *in6_dev;
328 struct neigh_parms *parms;
329 int is_multicast = ipv6_addr_is_multicast(addr);
330
331 rcu_read_lock();
332 in6_dev = in6_dev_get(dev);
333 if (in6_dev == NULL) {
334 rcu_read_unlock();
335 return -EINVAL;
336 }
337
338 parms = in6_dev->nd_parms;
339 __neigh_parms_put(neigh->parms);
340 neigh->parms = neigh_parms_clone(parms);
341 rcu_read_unlock();
342
343 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
344 if (dev->hard_header == NULL) {
345 neigh->nud_state = NUD_NOARP;
346 neigh->ops = &ndisc_direct_ops;
347 neigh->output = neigh->ops->queue_xmit;
348 } else {
349 if (is_multicast) {
350 neigh->nud_state = NUD_NOARP;
351 ndisc_mc_map(addr, neigh->ha, dev, 1);
352 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
353 neigh->nud_state = NUD_NOARP;
354 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
355 if (dev->flags&IFF_LOOPBACK)
356 neigh->type = RTN_LOCAL;
357 } else if (dev->flags&IFF_POINTOPOINT) {
358 neigh->nud_state = NUD_NOARP;
359 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
360 }
361 if (dev->hard_header_cache)
362 neigh->ops = &ndisc_hh_ops;
363 else
364 neigh->ops = &ndisc_generic_ops;
365 if (neigh->nud_state&NUD_VALID)
366 neigh->output = neigh->ops->connected_output;
367 else
368 neigh->output = neigh->ops->output;
369 }
370 in6_dev_put(in6_dev);
371 return 0;
372 }
373
374 static int pndisc_constructor(struct pneigh_entry *n)
375 {
376 struct in6_addr *addr = (struct in6_addr*)&n->key;
377 struct in6_addr maddr;
378 struct net_device *dev = n->dev;
379
380 if (dev == NULL || __in6_dev_get(dev) == NULL)
381 return -EINVAL;
382 addrconf_addr_solict_mult(addr, &maddr);
383 ipv6_dev_mc_inc(dev, &maddr);
384 return 0;
385 }
386
387 static void pndisc_destructor(struct pneigh_entry *n)
388 {
389 struct in6_addr *addr = (struct in6_addr*)&n->key;
390 struct in6_addr maddr;
391 struct net_device *dev = n->dev;
392
393 if (dev == NULL || __in6_dev_get(dev) == NULL)
394 return;
395 addrconf_addr_solict_mult(addr, &maddr);
396 ipv6_dev_mc_dec(dev, &maddr);
397 }
398
399 /*
400 * Send a Neighbour Advertisement
401 */
402
403 static inline void ndisc_flow_init(struct flowi *fl, u8 type,
404 struct in6_addr *saddr, struct in6_addr *daddr)
405 {
406 memset(fl, 0, sizeof(*fl));
407 ipv6_addr_copy(&fl->fl6_src, saddr);
408 ipv6_addr_copy(&fl->fl6_dst, daddr);
409 fl->proto = IPPROTO_ICMPV6;
410 fl->fl_icmp_type = type;
411 fl->fl_icmp_code = 0;
412 }
413
414 static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
415 struct in6_addr *daddr, struct in6_addr *solicited_addr,
416 int router, int solicited, int override, int inc_opt)
417 {
418 struct in6_addr tmpaddr;
419 struct inet6_ifaddr *ifp;
420 struct inet6_dev *idev;
421 struct flowi fl;
422 struct dst_entry* dst;
423 struct sock *sk = ndisc_socket->sk;
424 struct in6_addr *src_addr;
425 struct nd_msg *msg;
426 int len;
427 struct sk_buff *skb;
428 int err;
429
430 len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
431
432 /* for anycast or proxy, solicited_addr != src_addr */
433 ifp = ipv6_get_ifaddr(solicited_addr, dev, 1);
434 if (ifp) {
435 src_addr = solicited_addr;
436 in6_ifa_put(ifp);
437 } else {
438 if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
439 return;
440 src_addr = &tmpaddr;
441 }
442
443 ndisc_flow_init(&fl, NDISC_NEIGHBOUR_ADVERTISEMENT, src_addr, daddr);
444
445 dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
446 if (!dst)
447 return;
448
449 err = xfrm_lookup(&dst, &fl, NULL, 0);
450 if (err < 0)
451 return;
452
453 if (inc_opt) {
454 if (dev->addr_len)
455 len += ndisc_opt_addr_space(dev);
456 else
457 inc_opt = 0;
458 }
459
460 skb = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
461 1, &err);
462
463 if (skb == NULL) {
464 ND_PRINTK0(KERN_ERR
465 "ICMPv6 NA: %s() failed to allocate an skb.\n",
466 __FUNCTION__);
467 dst_release(dst);
468 return;
469 }
470
471 skb_reserve(skb, LL_RESERVED_SPACE(dev));
472 ip6_nd_hdr(sk, skb, dev, src_addr, daddr, IPPROTO_ICMPV6, len);
473
474 msg = (struct nd_msg *)skb_put(skb, len);
475 skb->h.raw = (unsigned char*)msg;
476
477 msg->icmph.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
478 msg->icmph.icmp6_code = 0;
479 msg->icmph.icmp6_cksum = 0;
480
481 msg->icmph.icmp6_unused = 0;
482 msg->icmph.icmp6_router = router;
483 msg->icmph.icmp6_solicited = solicited;
484 msg->icmph.icmp6_override = !!override;
485
486 /* Set the target address. */
487 ipv6_addr_copy(&msg->target, solicited_addr);
488
489 if (inc_opt)
490 ndisc_fill_addr_option(msg->opt, ND_OPT_TARGET_LL_ADDR, dev->dev_addr,
491 dev->addr_len, dev->type);
492
493 /* checksum */
494 msg->icmph.icmp6_cksum = csum_ipv6_magic(src_addr, daddr, len,
495 IPPROTO_ICMPV6,
496 csum_partial((__u8 *) msg,
497 len, 0));
498
499 skb->dst = dst;
500 idev = in6_dev_get(dst->dev);
501 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
502 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
503 if (!err) {
504 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTNEIGHBORADVERTISEMENTS);
505 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
506 }
507
508 if (likely(idev != NULL))
509 in6_dev_put(idev);
510 }
511
512 void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
513 struct in6_addr *solicit,
514 struct in6_addr *daddr, struct in6_addr *saddr)
515 {
516 struct flowi fl;
517 struct dst_entry* dst;
518 struct inet6_dev *idev;
519 struct sock *sk = ndisc_socket->sk;
520 struct sk_buff *skb;
521 struct nd_msg *msg;
522 struct in6_addr addr_buf;
523 int len;
524 int err;
525 int send_llinfo;
526
527 if (saddr == NULL) {
528 if (ipv6_get_lladdr(dev, &addr_buf))
529 return;
530 saddr = &addr_buf;
531 }
532
533 ndisc_flow_init(&fl, NDISC_NEIGHBOUR_SOLICITATION, saddr, daddr);
534
535 dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
536 if (!dst)
537 return;
538
539 err = xfrm_lookup(&dst, &fl, NULL, 0);
540 if (err < 0)
541 return;
542
543 len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
544 send_llinfo = dev->addr_len && !ipv6_addr_any(saddr);
545 if (send_llinfo)
546 len += ndisc_opt_addr_space(dev);
547
548 skb = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
549 1, &err);
550 if (skb == NULL) {
551 ND_PRINTK0(KERN_ERR
552 "ICMPv6 NA: %s() failed to allocate an skb.\n",
553 __FUNCTION__);
554 dst_release(dst);
555 return;
556 }
557
558 skb_reserve(skb, LL_RESERVED_SPACE(dev));
559 ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
560
561 msg = (struct nd_msg *)skb_put(skb, len);
562 skb->h.raw = (unsigned char*)msg;
563 msg->icmph.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION;
564 msg->icmph.icmp6_code = 0;
565 msg->icmph.icmp6_cksum = 0;
566 msg->icmph.icmp6_unused = 0;
567
568 /* Set the target address. */
569 ipv6_addr_copy(&msg->target, solicit);
570
571 if (send_llinfo)
572 ndisc_fill_addr_option(msg->opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr,
573 dev->addr_len, dev->type);
574
575 /* checksum */
576 msg->icmph.icmp6_cksum = csum_ipv6_magic(&skb->nh.ipv6h->saddr,
577 daddr, len,
578 IPPROTO_ICMPV6,
579 csum_partial((__u8 *) msg,
580 len, 0));
581 /* send it! */
582 skb->dst = dst;
583 idev = in6_dev_get(dst->dev);
584 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
585 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
586 if (!err) {
587 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTNEIGHBORSOLICITS);
588 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
589 }
590
591 if (likely(idev != NULL))
592 in6_dev_put(idev);
593 }
594
595 void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
596 struct in6_addr *daddr)
597 {
598 struct flowi fl;
599 struct dst_entry* dst;
600 struct inet6_dev *idev;
601 struct sock *sk = ndisc_socket->sk;
602 struct sk_buff *skb;
603 struct icmp6hdr *hdr;
604 __u8 * opt;
605 int len;
606 int err;
607
608 ndisc_flow_init(&fl, NDISC_ROUTER_SOLICITATION, saddr, daddr);
609
610 dst = ndisc_dst_alloc(dev, NULL, daddr, ip6_output);
611 if (!dst)
612 return;
613
614 err = xfrm_lookup(&dst, &fl, NULL, 0);
615 if (err < 0)
616 return;
617
618 len = sizeof(struct icmp6hdr);
619 if (dev->addr_len)
620 len += ndisc_opt_addr_space(dev);
621
622 skb = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
623 1, &err);
624 if (skb == NULL) {
625 ND_PRINTK0(KERN_ERR
626 "ICMPv6 RS: %s() failed to allocate an skb.\n",
627 __FUNCTION__);
628 dst_release(dst);
629 return;
630 }
631
632 skb_reserve(skb, LL_RESERVED_SPACE(dev));
633 ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
634
635 hdr = (struct icmp6hdr *)skb_put(skb, len);
636 skb->h.raw = (unsigned char*)hdr;
637 hdr->icmp6_type = NDISC_ROUTER_SOLICITATION;
638 hdr->icmp6_code = 0;
639 hdr->icmp6_cksum = 0;
640 hdr->icmp6_unused = 0;
641
642 opt = (u8*) (hdr + 1);
643
644 if (dev->addr_len)
645 ndisc_fill_addr_option(opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr,
646 dev->addr_len, dev->type);
647
648 /* checksum */
649 hdr->icmp6_cksum = csum_ipv6_magic(&skb->nh.ipv6h->saddr, daddr, len,
650 IPPROTO_ICMPV6,
651 csum_partial((__u8 *) hdr, len, 0));
652
653 /* send it! */
654 skb->dst = dst;
655 idev = in6_dev_get(dst->dev);
656 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
657 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
658 if (!err) {
659 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTROUTERSOLICITS);
660 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
661 }
662
663 if (likely(idev != NULL))
664 in6_dev_put(idev);
665 }
666
667
668 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
669 {
670 /*
671 * "The sender MUST return an ICMP
672 * destination unreachable"
673 */
674 dst_link_failure(skb);
675 kfree_skb(skb);
676 }
677
678 /* Called with locked neigh: either read or both */
679
680 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
681 {
682 struct in6_addr *saddr = NULL;
683 struct in6_addr mcaddr;
684 struct net_device *dev = neigh->dev;
685 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
686 int probes = atomic_read(&neigh->probes);
687
688 if (skb && ipv6_chk_addr(&skb->nh.ipv6h->saddr, dev, 1))
689 saddr = &skb->nh.ipv6h->saddr;
690
691 if ((probes -= neigh->parms->ucast_probes) < 0) {
692 if (!(neigh->nud_state & NUD_VALID)) {
693 ND_PRINTK1(KERN_DEBUG
694 "%s(): trying to ucast probe in NUD_INVALID: "
695 NIP6_FMT "\n",
696 __FUNCTION__,
697 NIP6(*target));
698 }
699 ndisc_send_ns(dev, neigh, target, target, saddr);
700 } else if ((probes -= neigh->parms->app_probes) < 0) {
701 #ifdef CONFIG_ARPD
702 neigh_app_ns(neigh);
703 #endif
704 } else {
705 addrconf_addr_solict_mult(target, &mcaddr);
706 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
707 }
708 }
709
710 static void ndisc_recv_ns(struct sk_buff *skb)
711 {
712 struct nd_msg *msg = (struct nd_msg *)skb->h.raw;
713 struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
714 struct in6_addr *daddr = &skb->nh.ipv6h->daddr;
715 u8 *lladdr = NULL;
716 u32 ndoptlen = skb->tail - msg->opt;
717 struct ndisc_options ndopts;
718 struct net_device *dev = skb->dev;
719 struct inet6_ifaddr *ifp;
720 struct inet6_dev *idev = NULL;
721 struct neighbour *neigh;
722 int dad = ipv6_addr_any(saddr);
723 int inc;
724
725 if (ipv6_addr_is_multicast(&msg->target)) {
726 ND_PRINTK2(KERN_WARNING
727 "ICMPv6 NS: multicast target address");
728 return;
729 }
730
731 /*
732 * RFC2461 7.1.1:
733 * DAD has to be destined for solicited node multicast address.
734 */
735 if (dad &&
736 !(daddr->s6_addr32[0] == htonl(0xff020000) &&
737 daddr->s6_addr32[1] == htonl(0x00000000) &&
738 daddr->s6_addr32[2] == htonl(0x00000001) &&
739 daddr->s6_addr [12] == 0xff )) {
740 ND_PRINTK2(KERN_WARNING
741 "ICMPv6 NS: bad DAD packet (wrong destination)\n");
742 return;
743 }
744
745 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
746 ND_PRINTK2(KERN_WARNING
747 "ICMPv6 NS: invalid ND options\n");
748 return;
749 }
750
751 if (ndopts.nd_opts_src_lladdr) {
752 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
753 if (!lladdr) {
754 ND_PRINTK2(KERN_WARNING
755 "ICMPv6 NS: invalid link-layer address length\n");
756 return;
757 }
758
759 /* RFC2461 7.1.1:
760 * If the IP source address is the unspecified address,
761 * there MUST NOT be source link-layer address option
762 * in the message.
763 */
764 if (dad) {
765 ND_PRINTK2(KERN_WARNING
766 "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
767 return;
768 }
769 }
770
771 inc = ipv6_addr_is_multicast(daddr);
772
773 if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1)) != NULL) {
774 if (ifp->flags & IFA_F_TENTATIVE) {
775 /* Address is tentative. If the source
776 is unspecified address, it is someone
777 does DAD, otherwise we ignore solicitations
778 until DAD timer expires.
779 */
780 if (!dad)
781 goto out;
782 if (dev->type == ARPHRD_IEEE802_TR) {
783 unsigned char *sadr = skb->mac.raw;
784 if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
785 sadr[9] == dev->dev_addr[1] &&
786 sadr[10] == dev->dev_addr[2] &&
787 sadr[11] == dev->dev_addr[3] &&
788 sadr[12] == dev->dev_addr[4] &&
789 sadr[13] == dev->dev_addr[5]) {
790 /* looped-back to us */
791 goto out;
792 }
793 }
794 addrconf_dad_failure(ifp);
795 return;
796 }
797
798 idev = ifp->idev;
799 } else {
800 idev = in6_dev_get(dev);
801 if (!idev) {
802 /* XXX: count this drop? */
803 return;
804 }
805
806 if (ipv6_chk_acast_addr(dev, &msg->target) ||
807 (idev->cnf.forwarding &&
808 pneigh_lookup(&nd_tbl, &msg->target, dev, 0))) {
809 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
810 skb->pkt_type != PACKET_HOST &&
811 inc != 0 &&
812 idev->nd_parms->proxy_delay != 0) {
813 /*
814 * for anycast or proxy,
815 * sender should delay its response
816 * by a random time between 0 and
817 * MAX_ANYCAST_DELAY_TIME seconds.
818 * (RFC2461) -- yoshfuji
819 */
820 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
821 if (n)
822 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
823 goto out;
824 }
825 } else
826 goto out;
827 }
828
829 if (dad) {
830 struct in6_addr maddr;
831
832 ipv6_addr_all_nodes(&maddr);
833 ndisc_send_na(dev, NULL, &maddr, &msg->target,
834 idev->cnf.forwarding, 0, (ifp != NULL), 1);
835 goto out;
836 }
837
838 if (inc)
839 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
840 else
841 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
842
843 /*
844 * update / create cache entry
845 * for the source address
846 */
847 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
848 !inc || lladdr || !dev->addr_len);
849 if (neigh)
850 neigh_update(neigh, lladdr, NUD_STALE,
851 NEIGH_UPDATE_F_WEAK_OVERRIDE|
852 NEIGH_UPDATE_F_OVERRIDE);
853 if (neigh || !dev->hard_header) {
854 ndisc_send_na(dev, neigh, saddr, &msg->target,
855 idev->cnf.forwarding,
856 1, (ifp != NULL && inc), inc);
857 if (neigh)
858 neigh_release(neigh);
859 }
860
861 out:
862 if (ifp)
863 in6_ifa_put(ifp);
864 else
865 in6_dev_put(idev);
866
867 return;
868 }
869
870 static void ndisc_recv_na(struct sk_buff *skb)
871 {
872 struct nd_msg *msg = (struct nd_msg *)skb->h.raw;
873 struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
874 struct in6_addr *daddr = &skb->nh.ipv6h->daddr;
875 u8 *lladdr = NULL;
876 u32 ndoptlen = skb->tail - msg->opt;
877 struct ndisc_options ndopts;
878 struct net_device *dev = skb->dev;
879 struct inet6_ifaddr *ifp;
880 struct neighbour *neigh;
881
882 if (skb->len < sizeof(struct nd_msg)) {
883 ND_PRINTK2(KERN_WARNING
884 "ICMPv6 NA: packet too short\n");
885 return;
886 }
887
888 if (ipv6_addr_is_multicast(&msg->target)) {
889 ND_PRINTK2(KERN_WARNING
890 "ICMPv6 NA: target address is multicast.\n");
891 return;
892 }
893
894 if (ipv6_addr_is_multicast(daddr) &&
895 msg->icmph.icmp6_solicited) {
896 ND_PRINTK2(KERN_WARNING
897 "ICMPv6 NA: solicited NA is multicasted.\n");
898 return;
899 }
900
901 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
902 ND_PRINTK2(KERN_WARNING
903 "ICMPv6 NS: invalid ND option\n");
904 return;
905 }
906 if (ndopts.nd_opts_tgt_lladdr) {
907 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
908 if (!lladdr) {
909 ND_PRINTK2(KERN_WARNING
910 "ICMPv6 NA: invalid link-layer address length\n");
911 return;
912 }
913 }
914 if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1))) {
915 if (ifp->flags & IFA_F_TENTATIVE) {
916 addrconf_dad_failure(ifp);
917 return;
918 }
919 /* What should we make now? The advertisement
920 is invalid, but ndisc specs say nothing
921 about it. It could be misconfiguration, or
922 an smart proxy agent tries to help us :-)
923 */
924 ND_PRINTK1(KERN_WARNING
925 "ICMPv6 NA: someone advertises our address on %s!\n",
926 ifp->idev->dev->name);
927 in6_ifa_put(ifp);
928 return;
929 }
930 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
931
932 if (neigh) {
933 u8 old_flags = neigh->flags;
934
935 if (neigh->nud_state & NUD_FAILED)
936 goto out;
937
938 neigh_update(neigh, lladdr,
939 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
940 NEIGH_UPDATE_F_WEAK_OVERRIDE|
941 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
942 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
943 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
944
945 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
946 /*
947 * Change: router to host
948 */
949 struct rt6_info *rt;
950 rt = rt6_get_dflt_router(saddr, dev);
951 if (rt)
952 ip6_del_rt(rt, NULL, NULL, NULL);
953 }
954
955 out:
956 neigh_release(neigh);
957 }
958 }
959
960 static void ndisc_recv_rs(struct sk_buff *skb)
961 {
962 struct rs_msg *rs_msg = (struct rs_msg *) skb->h.raw;
963 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
964 struct neighbour *neigh;
965 struct inet6_dev *idev;
966 struct in6_addr *saddr = &skb->nh.ipv6h->saddr;
967 struct ndisc_options ndopts;
968 u8 *lladdr = NULL;
969
970 if (skb->len < sizeof(*rs_msg))
971 return;
972
973 idev = in6_dev_get(skb->dev);
974 if (!idev) {
975 if (net_ratelimit())
976 ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
977 return;
978 }
979
980 /* Don't accept RS if we're not in router mode */
981 if (!idev->cnf.forwarding)
982 goto out;
983
984 /*
985 * Don't update NCE if src = ::;
986 * this implies that the source node has no ip address assigned yet.
987 */
988 if (ipv6_addr_any(saddr))
989 goto out;
990
991 /* Parse ND options */
992 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
993 if (net_ratelimit())
994 ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
995 goto out;
996 }
997
998 if (ndopts.nd_opts_src_lladdr) {
999 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1000 skb->dev);
1001 if (!lladdr)
1002 goto out;
1003 }
1004
1005 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1006 if (neigh) {
1007 neigh_update(neigh, lladdr, NUD_STALE,
1008 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1009 NEIGH_UPDATE_F_OVERRIDE|
1010 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1011 neigh_release(neigh);
1012 }
1013 out:
1014 in6_dev_put(idev);
1015 }
1016
1017 static void ndisc_router_discovery(struct sk_buff *skb)
1018 {
1019 struct ra_msg *ra_msg = (struct ra_msg *) skb->h.raw;
1020 struct neighbour *neigh = NULL;
1021 struct inet6_dev *in6_dev;
1022 struct rt6_info *rt = NULL;
1023 int lifetime;
1024 struct ndisc_options ndopts;
1025 int optlen;
1026
1027 __u8 * opt = (__u8 *)(ra_msg + 1);
1028
1029 optlen = (skb->tail - skb->h.raw) - sizeof(struct ra_msg);
1030
1031 if (!(ipv6_addr_type(&skb->nh.ipv6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1032 ND_PRINTK2(KERN_WARNING
1033 "ICMPv6 RA: source address is not link-local.\n");
1034 return;
1035 }
1036 if (optlen < 0) {
1037 ND_PRINTK2(KERN_WARNING
1038 "ICMPv6 RA: packet too short\n");
1039 return;
1040 }
1041
1042 /*
1043 * set the RA_RECV flag in the interface
1044 */
1045
1046 in6_dev = in6_dev_get(skb->dev);
1047 if (in6_dev == NULL) {
1048 ND_PRINTK0(KERN_ERR
1049 "ICMPv6 RA: can't find inet6 device for %s.\n",
1050 skb->dev->name);
1051 return;
1052 }
1053 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra) {
1054 in6_dev_put(in6_dev);
1055 return;
1056 }
1057
1058 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1059 in6_dev_put(in6_dev);
1060 ND_PRINTK2(KERN_WARNING
1061 "ICMP6 RA: invalid ND options\n");
1062 return;
1063 }
1064
1065 if (in6_dev->if_flags & IF_RS_SENT) {
1066 /*
1067 * flag that an RA was received after an RS was sent
1068 * out on this interface.
1069 */
1070 in6_dev->if_flags |= IF_RA_RCVD;
1071 }
1072
1073 /*
1074 * Remember the managed/otherconf flags from most recently
1075 * received RA message (RFC 2462) -- yoshfuji
1076 */
1077 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1078 IF_RA_OTHERCONF)) |
1079 (ra_msg->icmph.icmp6_addrconf_managed ?
1080 IF_RA_MANAGED : 0) |
1081 (ra_msg->icmph.icmp6_addrconf_other ?
1082 IF_RA_OTHERCONF : 0);
1083
1084 if (!in6_dev->cnf.accept_ra_defrtr)
1085 goto skip_defrtr;
1086
1087 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1088
1089 rt = rt6_get_dflt_router(&skb->nh.ipv6h->saddr, skb->dev);
1090
1091 if (rt)
1092 neigh = rt->rt6i_nexthop;
1093
1094 if (rt && lifetime == 0) {
1095 neigh_clone(neigh);
1096 ip6_del_rt(rt, NULL, NULL, NULL);
1097 rt = NULL;
1098 }
1099
1100 if (rt == NULL && lifetime) {
1101 ND_PRINTK3(KERN_DEBUG
1102 "ICMPv6 RA: adding default router.\n");
1103
1104 rt = rt6_add_dflt_router(&skb->nh.ipv6h->saddr, skb->dev);
1105 if (rt == NULL) {
1106 ND_PRINTK0(KERN_ERR
1107 "ICMPv6 RA: %s() failed to add default route.\n",
1108 __FUNCTION__);
1109 in6_dev_put(in6_dev);
1110 return;
1111 }
1112
1113 neigh = rt->rt6i_nexthop;
1114 if (neigh == NULL) {
1115 ND_PRINTK0(KERN_ERR
1116 "ICMPv6 RA: %s() got default router without neighbour.\n",
1117 __FUNCTION__);
1118 dst_release(&rt->u.dst);
1119 in6_dev_put(in6_dev);
1120 return;
1121 }
1122 neigh->flags |= NTF_ROUTER;
1123 }
1124
1125 if (rt)
1126 rt->rt6i_expires = jiffies + (HZ * lifetime);
1127
1128 if (ra_msg->icmph.icmp6_hop_limit) {
1129 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1130 if (rt)
1131 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit;
1132 }
1133
1134 skip_defrtr:
1135
1136 /*
1137 * Update Reachable Time and Retrans Timer
1138 */
1139
1140 if (in6_dev->nd_parms) {
1141 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1142
1143 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1144 rtime = (rtime*HZ)/1000;
1145 if (rtime < HZ/10)
1146 rtime = HZ/10;
1147 in6_dev->nd_parms->retrans_time = rtime;
1148 in6_dev->tstamp = jiffies;
1149 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1150 }
1151
1152 rtime = ntohl(ra_msg->reachable_time);
1153 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1154 rtime = (rtime*HZ)/1000;
1155
1156 if (rtime < HZ/10)
1157 rtime = HZ/10;
1158
1159 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1160 in6_dev->nd_parms->base_reachable_time = rtime;
1161 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1162 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1163 in6_dev->tstamp = jiffies;
1164 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1165 }
1166 }
1167 }
1168
1169 /*
1170 * Process options.
1171 */
1172
1173 if (!neigh)
1174 neigh = __neigh_lookup(&nd_tbl, &skb->nh.ipv6h->saddr,
1175 skb->dev, 1);
1176 if (neigh) {
1177 u8 *lladdr = NULL;
1178 if (ndopts.nd_opts_src_lladdr) {
1179 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1180 skb->dev);
1181 if (!lladdr) {
1182 ND_PRINTK2(KERN_WARNING
1183 "ICMPv6 RA: invalid link-layer address length\n");
1184 goto out;
1185 }
1186 }
1187 neigh_update(neigh, lladdr, NUD_STALE,
1188 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1189 NEIGH_UPDATE_F_OVERRIDE|
1190 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1191 NEIGH_UPDATE_F_ISROUTER);
1192 }
1193
1194 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1195 struct nd_opt_hdr *p;
1196 for (p = ndopts.nd_opts_pi;
1197 p;
1198 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1199 addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
1200 }
1201 }
1202
1203 if (ndopts.nd_opts_mtu) {
1204 u32 mtu;
1205
1206 memcpy(&mtu, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1207 mtu = ntohl(mtu);
1208
1209 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1210 ND_PRINTK2(KERN_WARNING
1211 "ICMPv6 RA: invalid mtu: %d\n",
1212 mtu);
1213 } else if (in6_dev->cnf.mtu6 != mtu) {
1214 in6_dev->cnf.mtu6 = mtu;
1215
1216 if (rt)
1217 rt->u.dst.metrics[RTAX_MTU-1] = mtu;
1218
1219 rt6_mtu_change(skb->dev, mtu);
1220 }
1221 }
1222
1223 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1224 ND_PRINTK2(KERN_WARNING
1225 "ICMPv6 RA: invalid RA options");
1226 }
1227 out:
1228 if (rt)
1229 dst_release(&rt->u.dst);
1230 else if (neigh)
1231 neigh_release(neigh);
1232 in6_dev_put(in6_dev);
1233 }
1234
1235 static void ndisc_redirect_rcv(struct sk_buff *skb)
1236 {
1237 struct inet6_dev *in6_dev;
1238 struct icmp6hdr *icmph;
1239 struct in6_addr *dest;
1240 struct in6_addr *target; /* new first hop to destination */
1241 struct neighbour *neigh;
1242 int on_link = 0;
1243 struct ndisc_options ndopts;
1244 int optlen;
1245 u8 *lladdr = NULL;
1246
1247 if (!(ipv6_addr_type(&skb->nh.ipv6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1248 ND_PRINTK2(KERN_WARNING
1249 "ICMPv6 Redirect: source address is not link-local.\n");
1250 return;
1251 }
1252
1253 optlen = skb->tail - skb->h.raw;
1254 optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1255
1256 if (optlen < 0) {
1257 ND_PRINTK2(KERN_WARNING
1258 "ICMPv6 Redirect: packet too short\n");
1259 return;
1260 }
1261
1262 icmph = (struct icmp6hdr *) skb->h.raw;
1263 target = (struct in6_addr *) (icmph + 1);
1264 dest = target + 1;
1265
1266 if (ipv6_addr_is_multicast(dest)) {
1267 ND_PRINTK2(KERN_WARNING
1268 "ICMPv6 Redirect: destination address is multicast.\n");
1269 return;
1270 }
1271
1272 if (ipv6_addr_equal(dest, target)) {
1273 on_link = 1;
1274 } else if (!(ipv6_addr_type(target) & IPV6_ADDR_LINKLOCAL)) {
1275 ND_PRINTK2(KERN_WARNING
1276 "ICMPv6 Redirect: target address is not link-local.\n");
1277 return;
1278 }
1279
1280 in6_dev = in6_dev_get(skb->dev);
1281 if (!in6_dev)
1282 return;
1283 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) {
1284 in6_dev_put(in6_dev);
1285 return;
1286 }
1287
1288 /* RFC2461 8.1:
1289 * The IP source address of the Redirect MUST be the same as the current
1290 * first-hop router for the specified ICMP Destination Address.
1291 */
1292
1293 if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1294 ND_PRINTK2(KERN_WARNING
1295 "ICMPv6 Redirect: invalid ND options\n");
1296 in6_dev_put(in6_dev);
1297 return;
1298 }
1299 if (ndopts.nd_opts_tgt_lladdr) {
1300 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1301 skb->dev);
1302 if (!lladdr) {
1303 ND_PRINTK2(KERN_WARNING
1304 "ICMPv6 Redirect: invalid link-layer address length\n");
1305 in6_dev_put(in6_dev);
1306 return;
1307 }
1308 }
1309
1310 neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1311 if (neigh) {
1312 rt6_redirect(dest, &skb->nh.ipv6h->saddr, neigh, lladdr,
1313 on_link);
1314 neigh_release(neigh);
1315 }
1316 in6_dev_put(in6_dev);
1317 }
1318
1319 void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
1320 struct in6_addr *target)
1321 {
1322 struct sock *sk = ndisc_socket->sk;
1323 int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1324 struct sk_buff *buff;
1325 struct icmp6hdr *icmph;
1326 struct in6_addr saddr_buf;
1327 struct in6_addr *addrp;
1328 struct net_device *dev;
1329 struct rt6_info *rt;
1330 struct dst_entry *dst;
1331 struct inet6_dev *idev;
1332 struct flowi fl;
1333 u8 *opt;
1334 int rd_len;
1335 int err;
1336 int hlen;
1337 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1338
1339 dev = skb->dev;
1340
1341 if (ipv6_get_lladdr(dev, &saddr_buf)) {
1342 ND_PRINTK2(KERN_WARNING
1343 "ICMPv6 Redirect: no link-local address on %s\n",
1344 dev->name);
1345 return;
1346 }
1347
1348 ndisc_flow_init(&fl, NDISC_REDIRECT, &saddr_buf, &skb->nh.ipv6h->saddr);
1349
1350 dst = ip6_route_output(NULL, &fl);
1351 if (dst == NULL)
1352 return;
1353
1354 err = xfrm_lookup(&dst, &fl, NULL, 0);
1355 if (err)
1356 return;
1357
1358 rt = (struct rt6_info *) dst;
1359
1360 if (rt->rt6i_flags & RTF_GATEWAY) {
1361 ND_PRINTK2(KERN_WARNING
1362 "ICMPv6 Redirect: destination is not a neighbour.\n");
1363 dst_release(dst);
1364 return;
1365 }
1366 if (!xrlim_allow(dst, 1*HZ)) {
1367 dst_release(dst);
1368 return;
1369 }
1370
1371 if (dev->addr_len) {
1372 read_lock_bh(&neigh->lock);
1373 if (neigh->nud_state & NUD_VALID) {
1374 memcpy(ha_buf, neigh->ha, dev->addr_len);
1375 read_unlock_bh(&neigh->lock);
1376 ha = ha_buf;
1377 len += ndisc_opt_addr_space(dev);
1378 } else
1379 read_unlock_bh(&neigh->lock);
1380 }
1381
1382 rd_len = min_t(unsigned int,
1383 IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1384 rd_len &= ~0x7;
1385 len += rd_len;
1386
1387 buff = sock_alloc_send_skb(sk, MAX_HEADER + len + LL_RESERVED_SPACE(dev),
1388 1, &err);
1389 if (buff == NULL) {
1390 ND_PRINTK0(KERN_ERR
1391 "ICMPv6 Redirect: %s() failed to allocate an skb.\n",
1392 __FUNCTION__);
1393 dst_release(dst);
1394 return;
1395 }
1396
1397 hlen = 0;
1398
1399 skb_reserve(buff, LL_RESERVED_SPACE(dev));
1400 ip6_nd_hdr(sk, buff, dev, &saddr_buf, &skb->nh.ipv6h->saddr,
1401 IPPROTO_ICMPV6, len);
1402
1403 icmph = (struct icmp6hdr *)skb_put(buff, len);
1404 buff->h.raw = (unsigned char*)icmph;
1405
1406 memset(icmph, 0, sizeof(struct icmp6hdr));
1407 icmph->icmp6_type = NDISC_REDIRECT;
1408
1409 /*
1410 * copy target and destination addresses
1411 */
1412
1413 addrp = (struct in6_addr *)(icmph + 1);
1414 ipv6_addr_copy(addrp, target);
1415 addrp++;
1416 ipv6_addr_copy(addrp, &skb->nh.ipv6h->daddr);
1417
1418 opt = (u8*) (addrp + 1);
1419
1420 /*
1421 * include target_address option
1422 */
1423
1424 if (ha)
1425 opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1426 dev->addr_len, dev->type);
1427
1428 /*
1429 * build redirect option and copy skb over to the new packet.
1430 */
1431
1432 memset(opt, 0, 8);
1433 *(opt++) = ND_OPT_REDIRECT_HDR;
1434 *(opt++) = (rd_len >> 3);
1435 opt += 6;
1436
1437 memcpy(opt, skb->nh.ipv6h, rd_len - 8);
1438
1439 icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &skb->nh.ipv6h->saddr,
1440 len, IPPROTO_ICMPV6,
1441 csum_partial((u8 *) icmph, len, 0));
1442
1443 buff->dst = dst;
1444 idev = in6_dev_get(dst->dev);
1445 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
1446 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, buff, NULL, dst->dev, dst_output);
1447 if (!err) {
1448 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTREDIRECTS);
1449 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
1450 }
1451
1452 if (likely(idev != NULL))
1453 in6_dev_put(idev);
1454 }
1455
1456 static void pndisc_redo(struct sk_buff *skb)
1457 {
1458 ndisc_recv_ns(skb);
1459 kfree_skb(skb);
1460 }
1461
1462 int ndisc_rcv(struct sk_buff *skb)
1463 {
1464 struct nd_msg *msg;
1465
1466 if (!pskb_may_pull(skb, skb->len))
1467 return 0;
1468
1469 msg = (struct nd_msg *) skb->h.raw;
1470
1471 __skb_push(skb, skb->data-skb->h.raw);
1472
1473 if (skb->nh.ipv6h->hop_limit != 255) {
1474 ND_PRINTK2(KERN_WARNING
1475 "ICMPv6 NDISC: invalid hop-limit: %d\n",
1476 skb->nh.ipv6h->hop_limit);
1477 return 0;
1478 }
1479
1480 if (msg->icmph.icmp6_code != 0) {
1481 ND_PRINTK2(KERN_WARNING
1482 "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
1483 msg->icmph.icmp6_code);
1484 return 0;
1485 }
1486
1487 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1488
1489 switch (msg->icmph.icmp6_type) {
1490 case NDISC_NEIGHBOUR_SOLICITATION:
1491 ndisc_recv_ns(skb);
1492 break;
1493
1494 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1495 ndisc_recv_na(skb);
1496 break;
1497
1498 case NDISC_ROUTER_SOLICITATION:
1499 ndisc_recv_rs(skb);
1500 break;
1501
1502 case NDISC_ROUTER_ADVERTISEMENT:
1503 ndisc_router_discovery(skb);
1504 break;
1505
1506 case NDISC_REDIRECT:
1507 ndisc_redirect_rcv(skb);
1508 break;
1509 };
1510
1511 return 0;
1512 }
1513
1514 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1515 {
1516 struct net_device *dev = ptr;
1517
1518 switch (event) {
1519 case NETDEV_CHANGEADDR:
1520 neigh_changeaddr(&nd_tbl, dev);
1521 fib6_run_gc(~0UL);
1522 break;
1523 case NETDEV_DOWN:
1524 neigh_ifdown(&nd_tbl, dev);
1525 fib6_run_gc(~0UL);
1526 break;
1527 default:
1528 break;
1529 }
1530
1531 return NOTIFY_DONE;
1532 }
1533
1534 static struct notifier_block ndisc_netdev_notifier = {
1535 .notifier_call = ndisc_netdev_event,
1536 };
1537
1538 #ifdef CONFIG_SYSCTL
1539 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1540 const char *func, const char *dev_name)
1541 {
1542 static char warncomm[TASK_COMM_LEN];
1543 static int warned;
1544 if (strcmp(warncomm, current->comm) && warned < 5) {
1545 strcpy(warncomm, current->comm);
1546 printk(KERN_WARNING
1547 "process `%s' is using deprecated sysctl (%s) "
1548 "net.ipv6.neigh.%s.%s; "
1549 "Use net.ipv6.neigh.%s.%s_ms "
1550 "instead.\n",
1551 warncomm, func,
1552 dev_name, ctl->procname,
1553 dev_name, ctl->procname);
1554 warned++;
1555 }
1556 }
1557
1558 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, struct file * filp, void __user *buffer, size_t *lenp, loff_t *ppos)
1559 {
1560 struct net_device *dev = ctl->extra1;
1561 struct inet6_dev *idev;
1562 int ret;
1563
1564 if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
1565 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
1566 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1567
1568 switch (ctl->ctl_name) {
1569 case NET_NEIGH_RETRANS_TIME:
1570 ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1571 break;
1572 case NET_NEIGH_REACHABLE_TIME:
1573 ret = proc_dointvec_jiffies(ctl, write,
1574 filp, buffer, lenp, ppos);
1575 break;
1576 case NET_NEIGH_RETRANS_TIME_MS:
1577 case NET_NEIGH_REACHABLE_TIME_MS:
1578 ret = proc_dointvec_ms_jiffies(ctl, write,
1579 filp, buffer, lenp, ppos);
1580 break;
1581 default:
1582 ret = -1;
1583 }
1584
1585 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1586 if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
1587 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
1588 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1589 idev->tstamp = jiffies;
1590 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1591 in6_dev_put(idev);
1592 }
1593 return ret;
1594 }
1595
1596 static int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl, int __user *name,
1597 int nlen, void __user *oldval,
1598 size_t __user *oldlenp,
1599 void __user *newval, size_t newlen,
1600 void **context)
1601 {
1602 struct net_device *dev = ctl->extra1;
1603 struct inet6_dev *idev;
1604 int ret;
1605
1606 if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
1607 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
1608 ndisc_warn_deprecated_sysctl(ctl, "procfs", dev ? dev->name : "default");
1609
1610 switch (ctl->ctl_name) {
1611 case NET_NEIGH_REACHABLE_TIME:
1612 ret = sysctl_jiffies(ctl, name, nlen,
1613 oldval, oldlenp, newval, newlen,
1614 context);
1615 break;
1616 case NET_NEIGH_RETRANS_TIME_MS:
1617 case NET_NEIGH_REACHABLE_TIME_MS:
1618 ret = sysctl_ms_jiffies(ctl, name, nlen,
1619 oldval, oldlenp, newval, newlen,
1620 context);
1621 break;
1622 default:
1623 ret = 0;
1624 }
1625
1626 if (newval && newlen && ret > 0 &&
1627 dev && (idev = in6_dev_get(dev)) != NULL) {
1628 if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
1629 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
1630 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1631 idev->tstamp = jiffies;
1632 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1633 in6_dev_put(idev);
1634 }
1635
1636 return ret;
1637 }
1638
1639 #endif
1640
1641 int __init ndisc_init(struct net_proto_family *ops)
1642 {
1643 struct ipv6_pinfo *np;
1644 struct sock *sk;
1645 int err;
1646
1647 err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6, &ndisc_socket);
1648 if (err < 0) {
1649 ND_PRINTK0(KERN_ERR
1650 "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n",
1651 err);
1652 ndisc_socket = NULL; /* For safety. */
1653 return err;
1654 }
1655
1656 sk = ndisc_socket->sk;
1657 np = inet6_sk(sk);
1658 sk->sk_allocation = GFP_ATOMIC;
1659 np->hop_limit = 255;
1660 /* Do not loopback ndisc messages */
1661 np->mc_loop = 0;
1662 sk->sk_prot->unhash(sk);
1663
1664 /*
1665 * Initialize the neighbour table
1666 */
1667
1668 neigh_table_init(&nd_tbl);
1669
1670 #ifdef CONFIG_SYSCTL
1671 neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH,
1672 "ipv6",
1673 &ndisc_ifinfo_sysctl_change,
1674 &ndisc_ifinfo_sysctl_strategy);
1675 #endif
1676
1677 register_netdevice_notifier(&ndisc_netdev_notifier);
1678 return 0;
1679 }
1680
1681 void ndisc_cleanup(void)
1682 {
1683 #ifdef CONFIG_SYSCTL
1684 neigh_sysctl_unregister(&nd_tbl.parms);
1685 #endif
1686 neigh_table_clear(&nd_tbl);
1687 sock_release(ndisc_socket);
1688 ndisc_socket = NULL; /* For safety. */
1689 }
linux 2.6 git repository for openrd