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Fix boot problem with iSeries lacking hugepage support
[linux-2.6/zen-sources.git] / net / ipv6 / ndisc.c
blob67997a74ddce15d85e43c8146a9ed62f91085f77
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 * Pierre Ynard : export userland ND options
19 * through netlink (RDNSS support)
20 * Lars Fenneberg : fixed MTU setting on receipt
21 * of an RA.
22 * Janos Farkas : kmalloc failure checks
23 * Alexey Kuznetsov : state machine reworked
24 * and moved to net/core.
25 * Pekka Savola : RFC2461 validation
26 * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
27 */
28
29 /* Set to 3 to get tracing... */
30 #define ND_DEBUG 1
31
32 #define ND_PRINTK(fmt, args...) do { if (net_ratelimit()) { printk(fmt, ## args); } } while(0)
33 #define ND_NOPRINTK(x...) do { ; } while(0)
34 #define ND_PRINTK0 ND_PRINTK
35 #define ND_PRINTK1 ND_NOPRINTK
36 #define ND_PRINTK2 ND_NOPRINTK
37 #define ND_PRINTK3 ND_NOPRINTK
38 #if ND_DEBUG >= 1
39 #undef ND_PRINTK1
40 #define ND_PRINTK1 ND_PRINTK
41 #endif
42 #if ND_DEBUG >= 2
43 #undef ND_PRINTK2
44 #define ND_PRINTK2 ND_PRINTK
45 #endif
46 #if ND_DEBUG >= 3
47 #undef ND_PRINTK3
48 #define ND_PRINTK3 ND_PRINTK
49 #endif
50
51 #include <linux/module.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_addr.h>
67 #include <linux/if_arp.h>
68 #include <linux/ipv6.h>
69 #include <linux/icmpv6.h>
70 #include <linux/jhash.h>
71
72 #include <net/sock.h>
73 #include <net/snmp.h>
74
75 #include <net/ipv6.h>
76 #include <net/protocol.h>
77 #include <net/ndisc.h>
78 #include <net/ip6_route.h>
79 #include <net/addrconf.h>
80 #include <net/icmp.h>
81
82 #include <net/netlink.h>
83 #include <linux/rtnetlink.h>
84
85 #include <net/flow.h>
86 #include <net/ip6_checksum.h>
87 #include <linux/proc_fs.h>
88
89 #include <linux/netfilter.h>
90 #include <linux/netfilter_ipv6.h>
91
92 static struct socket *ndisc_socket;
93
94 static u32 ndisc_hash(const void *pkey, const struct net_device *dev);
95 static int ndisc_constructor(struct neighbour *neigh);
96 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
97 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
98 static int pndisc_constructor(struct pneigh_entry *n);
99 static void pndisc_destructor(struct pneigh_entry *n);
100 static void pndisc_redo(struct sk_buff *skb);
101
102 static struct neigh_ops ndisc_generic_ops = {
103 .family = AF_INET6,
104 .solicit = ndisc_solicit,
105 .error_report = ndisc_error_report,
106 .output = neigh_resolve_output,
107 .connected_output = neigh_connected_output,
108 .hh_output = dev_queue_xmit,
109 .queue_xmit = dev_queue_xmit,
110 };
111
112 static struct neigh_ops ndisc_hh_ops = {
113 .family = AF_INET6,
114 .solicit = ndisc_solicit,
115 .error_report = ndisc_error_report,
116 .output = neigh_resolve_output,
117 .connected_output = neigh_resolve_output,
118 .hh_output = dev_queue_xmit,
119 .queue_xmit = dev_queue_xmit,
120 };
121
122
123 static struct neigh_ops ndisc_direct_ops = {
124 .family = AF_INET6,
125 .output = dev_queue_xmit,
126 .connected_output = dev_queue_xmit,
127 .hh_output = dev_queue_xmit,
128 .queue_xmit = dev_queue_xmit,
129 };
130
131 struct neigh_table nd_tbl = {
132 .family = AF_INET6,
133 .entry_size = sizeof(struct neighbour) + sizeof(struct in6_addr),
134 .key_len = sizeof(struct in6_addr),
135 .hash = ndisc_hash,
136 .constructor = ndisc_constructor,
137 .pconstructor = pndisc_constructor,
138 .pdestructor = pndisc_destructor,
139 .proxy_redo = pndisc_redo,
140 .id = "ndisc_cache",
141 .parms = {
142 .tbl = &nd_tbl,
143 .base_reachable_time = 30 * HZ,
144 .retrans_time = 1 * HZ,
145 .gc_staletime = 60 * HZ,
146 .reachable_time = 30 * HZ,
147 .delay_probe_time = 5 * HZ,
148 .queue_len = 3,
149 .ucast_probes = 3,
150 .mcast_probes = 3,
151 .anycast_delay = 1 * HZ,
152 .proxy_delay = (8 * HZ) / 10,
153 .proxy_qlen = 64,
154 },
155 .gc_interval = 30 * HZ,
156 .gc_thresh1 = 128,
157 .gc_thresh2 = 512,
158 .gc_thresh3 = 1024,
159 };
160
161 /* ND options */
162 struct ndisc_options {
163 struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
164 #ifdef CONFIG_IPV6_ROUTE_INFO
165 struct nd_opt_hdr *nd_opts_ri;
166 struct nd_opt_hdr *nd_opts_ri_end;
167 #endif
168 struct nd_opt_hdr *nd_useropts;
169 struct nd_opt_hdr *nd_useropts_end;
170 };
171
172 #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
173 #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR]
174 #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO]
175 #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END]
176 #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR]
177 #define nd_opts_mtu nd_opt_array[ND_OPT_MTU]
178
179 #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7)
180
181 /*
182 * Return the padding between the option length and the start of the
183 * link addr. Currently only IP-over-InfiniBand needs this, although
184 * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may
185 * also need a pad of 2.
186 */
187 static int ndisc_addr_option_pad(unsigned short type)
188 {
189 switch (type) {
190 case ARPHRD_INFINIBAND: return 2;
191 default: return 0;
192 }
193 }
194
195 static inline int ndisc_opt_addr_space(struct net_device *dev)
196 {
197 return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type));
198 }
199
200 static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len,
201 unsigned short addr_type)
202 {
203 int space = NDISC_OPT_SPACE(data_len);
204 int pad = ndisc_addr_option_pad(addr_type);
205
206 opt[0] = type;
207 opt[1] = space>>3;
208
209 memset(opt + 2, 0, pad);
210 opt += pad;
211 space -= pad;
212
213 memcpy(opt+2, data, data_len);
214 data_len += 2;
215 opt += data_len;
216 if ((space -= data_len) > 0)
217 memset(opt, 0, space);
218 return opt + space;
219 }
220
221 static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
222 struct nd_opt_hdr *end)
223 {
224 int type;
225 if (!cur || !end || cur >= end)
226 return NULL;
227 type = cur->nd_opt_type;
228 do {
229 cur = ((void *)cur) + (cur->nd_opt_len << 3);
230 } while(cur < end && cur->nd_opt_type != type);
231 return (cur <= end && cur->nd_opt_type == type ? cur : NULL);
232 }
233
234 static inline int ndisc_is_useropt(struct nd_opt_hdr *opt)
235 {
236 return (opt->nd_opt_type == ND_OPT_RDNSS);
237 }
238
239 static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur,
240 struct nd_opt_hdr *end)
241 {
242 if (!cur || !end || cur >= end)
243 return NULL;
244 do {
245 cur = ((void *)cur) + (cur->nd_opt_len << 3);
246 } while(cur < end && !ndisc_is_useropt(cur));
247 return (cur <= end && ndisc_is_useropt(cur) ? cur : NULL);
248 }
249
250 static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
251 struct ndisc_options *ndopts)
252 {
253 struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
254
255 if (!nd_opt || opt_len < 0 || !ndopts)
256 return NULL;
257 memset(ndopts, 0, sizeof(*ndopts));
258 while (opt_len) {
259 int l;
260 if (opt_len < sizeof(struct nd_opt_hdr))
261 return NULL;
262 l = nd_opt->nd_opt_len << 3;
263 if (opt_len < l || l == 0)
264 return NULL;
265 switch (nd_opt->nd_opt_type) {
266 case ND_OPT_SOURCE_LL_ADDR:
267 case ND_OPT_TARGET_LL_ADDR:
268 case ND_OPT_MTU:
269 case ND_OPT_REDIRECT_HDR:
270 if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
271 ND_PRINTK2(KERN_WARNING
272 "%s(): duplicated ND6 option found: type=%d\n",
273 __FUNCTION__,
274 nd_opt->nd_opt_type);
275 } else {
276 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
277 }
278 break;
279 case ND_OPT_PREFIX_INFO:
280 ndopts->nd_opts_pi_end = nd_opt;
281 if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
282 ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
283 break;
284 #ifdef CONFIG_IPV6_ROUTE_INFO
285 case ND_OPT_ROUTE_INFO:
286 ndopts->nd_opts_ri_end = nd_opt;
287 if (!ndopts->nd_opts_ri)
288 ndopts->nd_opts_ri = nd_opt;
289 break;
290 #endif
291 default:
292 if (ndisc_is_useropt(nd_opt)) {
293 ndopts->nd_useropts_end = nd_opt;
294 if (!ndopts->nd_useropts)
295 ndopts->nd_useropts = nd_opt;
296 } else {
297 /*
298 * Unknown options must be silently ignored,
299 * to accommodate future extension to the
300 * protocol.
301 */
302 ND_PRINTK2(KERN_NOTICE
303 "%s(): ignored unsupported option; type=%d, len=%d\n",
304 __FUNCTION__,
305 nd_opt->nd_opt_type, nd_opt->nd_opt_len);
306 }
307 }
308 opt_len -= l;
309 nd_opt = ((void *)nd_opt) + l;
310 }
311 return ndopts;
312 }
313
314 static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p,
315 struct net_device *dev)
316 {
317 u8 *lladdr = (u8 *)(p + 1);
318 int lladdrlen = p->nd_opt_len << 3;
319 int prepad = ndisc_addr_option_pad(dev->type);
320 if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad))
321 return NULL;
322 return (lladdr + prepad);
323 }
324
325 int ndisc_mc_map(struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
326 {
327 switch (dev->type) {
328 case ARPHRD_ETHER:
329 case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
330 case ARPHRD_FDDI:
331 ipv6_eth_mc_map(addr, buf);
332 return 0;
333 case ARPHRD_IEEE802_TR:
334 ipv6_tr_mc_map(addr,buf);
335 return 0;
336 case ARPHRD_ARCNET:
337 ipv6_arcnet_mc_map(addr, buf);
338 return 0;
339 case ARPHRD_INFINIBAND:
340 ipv6_ib_mc_map(addr, buf);
341 return 0;
342 default:
343 if (dir) {
344 memcpy(buf, dev->broadcast, dev->addr_len);
345 return 0;
346 }
347 }
348 return -EINVAL;
349 }
350
351 EXPORT_SYMBOL(ndisc_mc_map);
352
353 static u32 ndisc_hash(const void *pkey, const struct net_device *dev)
354 {
355 const u32 *p32 = pkey;
356 u32 addr_hash, i;
357
358 addr_hash = 0;
359 for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++)
360 addr_hash ^= *p32++;
361
362 return jhash_2words(addr_hash, dev->ifindex, nd_tbl.hash_rnd);
363 }
364
365 static int ndisc_constructor(struct neighbour *neigh)
366 {
367 struct in6_addr *addr = (struct in6_addr*)&neigh->primary_key;
368 struct net_device *dev = neigh->dev;
369 struct inet6_dev *in6_dev;
370 struct neigh_parms *parms;
371 int is_multicast = ipv6_addr_is_multicast(addr);
372
373 rcu_read_lock();
374 in6_dev = in6_dev_get(dev);
375 if (in6_dev == NULL) {
376 rcu_read_unlock();
377 return -EINVAL;
378 }
379
380 parms = in6_dev->nd_parms;
381 __neigh_parms_put(neigh->parms);
382 neigh->parms = neigh_parms_clone(parms);
383 rcu_read_unlock();
384
385 neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
386 if (!dev->header_ops) {
387 neigh->nud_state = NUD_NOARP;
388 neigh->ops = &ndisc_direct_ops;
389 neigh->output = neigh->ops->queue_xmit;
390 } else {
391 if (is_multicast) {
392 neigh->nud_state = NUD_NOARP;
393 ndisc_mc_map(addr, neigh->ha, dev, 1);
394 } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
395 neigh->nud_state = NUD_NOARP;
396 memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
397 if (dev->flags&IFF_LOOPBACK)
398 neigh->type = RTN_LOCAL;
399 } else if (dev->flags&IFF_POINTOPOINT) {
400 neigh->nud_state = NUD_NOARP;
401 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
402 }
403 if (dev->header_ops->cache)
404 neigh->ops = &ndisc_hh_ops;
405 else
406 neigh->ops = &ndisc_generic_ops;
407 if (neigh->nud_state&NUD_VALID)
408 neigh->output = neigh->ops->connected_output;
409 else
410 neigh->output = neigh->ops->output;
411 }
412 in6_dev_put(in6_dev);
413 return 0;
414 }
415
416 static int pndisc_constructor(struct pneigh_entry *n)
417 {
418 struct in6_addr *addr = (struct in6_addr*)&n->key;
419 struct in6_addr maddr;
420 struct net_device *dev = n->dev;
421
422 if (dev == NULL || __in6_dev_get(dev) == NULL)
423 return -EINVAL;
424 addrconf_addr_solict_mult(addr, &maddr);
425 ipv6_dev_mc_inc(dev, &maddr);
426 return 0;
427 }
428
429 static void pndisc_destructor(struct pneigh_entry *n)
430 {
431 struct in6_addr *addr = (struct in6_addr*)&n->key;
432 struct in6_addr maddr;
433 struct net_device *dev = n->dev;
434
435 if (dev == NULL || __in6_dev_get(dev) == NULL)
436 return;
437 addrconf_addr_solict_mult(addr, &maddr);
438 ipv6_dev_mc_dec(dev, &maddr);
439 }
440
441 /*
442 * Send a Neighbour Advertisement
443 */
444
445 static inline void ndisc_flow_init(struct flowi *fl, u8 type,
446 struct in6_addr *saddr, struct in6_addr *daddr,
447 int oif)
448 {
449 memset(fl, 0, sizeof(*fl));
450 ipv6_addr_copy(&fl->fl6_src, saddr);
451 ipv6_addr_copy(&fl->fl6_dst, daddr);
452 fl->proto = IPPROTO_ICMPV6;
453 fl->fl_icmp_type = type;
454 fl->fl_icmp_code = 0;
455 fl->oif = oif;
456 security_sk_classify_flow(ndisc_socket->sk, fl);
457 }
458
459 static void __ndisc_send(struct net_device *dev,
460 struct neighbour *neigh,
461 struct in6_addr *daddr, struct in6_addr *saddr,
462 struct icmp6hdr *icmp6h, struct in6_addr *target,
463 int llinfo)
464 {
465 struct flowi fl;
466 struct dst_entry *dst;
467 struct sock *sk = ndisc_socket->sk;
468 struct sk_buff *skb;
469 struct icmp6hdr *hdr;
470 struct inet6_dev *idev;
471 int len;
472 int err;
473 u8 *opt, type;
474
475 type = icmp6h->icmp6_type;
476
477 ndisc_flow_init(&fl, type, saddr, daddr,
478 dev->ifindex);
479
480 dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
481 if (!dst)
482 return;
483
484 err = xfrm_lookup(&dst, &fl, NULL, 0);
485 if (err < 0)
486 return;
487
488 if (!dev->addr_len)
489 llinfo = 0;
490
491 len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0);
492 if (llinfo)
493 len += ndisc_opt_addr_space(dev);
494
495 skb = sock_alloc_send_skb(sk,
496 (MAX_HEADER + sizeof(struct ipv6hdr) +
497 len + LL_RESERVED_SPACE(dev)),
498 1, &err);
499 if (!skb) {
500 ND_PRINTK0(KERN_ERR
501 "ICMPv6 ND: %s() failed to allocate an skb.\n",
502 __FUNCTION__);
503 dst_release(dst);
504 return;
505 }
506
507 skb_reserve(skb, LL_RESERVED_SPACE(dev));
508 ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
509
510 skb->transport_header = skb->tail;
511 skb_put(skb, len);
512
513 hdr = (struct icmp6hdr *)skb_transport_header(skb);
514 memcpy(hdr, icmp6h, sizeof(*hdr));
515
516 opt = skb_transport_header(skb) + sizeof(struct icmp6hdr);
517 if (target) {
518 ipv6_addr_copy((struct in6_addr *)opt, target);
519 opt += sizeof(*target);
520 }
521
522 if (llinfo)
523 ndisc_fill_addr_option(opt, llinfo, dev->dev_addr,
524 dev->addr_len, dev->type);
525
526 hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
527 IPPROTO_ICMPV6,
528 csum_partial((__u8 *) hdr,
529 len, 0));
530
531 skb->dst = dst;
532
533 idev = in6_dev_get(dst->dev);
534 IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
535
536 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output);
537 if (!err) {
538 ICMP6MSGOUT_INC_STATS(idev, type);
539 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
540 }
541
542 if (likely(idev != NULL))
543 in6_dev_put(idev);
544 }
545
546 static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
547 struct in6_addr *daddr, struct in6_addr *solicited_addr,
548 int router, int solicited, int override, int inc_opt)
549 {
550 struct in6_addr tmpaddr;
551 struct inet6_ifaddr *ifp;
552 struct in6_addr *src_addr;
553 struct icmp6hdr icmp6h = {
554 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
555 };
556
557 /* for anycast or proxy, solicited_addr != src_addr */
558 ifp = ipv6_get_ifaddr(solicited_addr, dev, 1);
559 if (ifp) {
560 src_addr = solicited_addr;
561 if (ifp->flags & IFA_F_OPTIMISTIC)
562 override = 0;
563 in6_ifa_put(ifp);
564 } else {
565 if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
566 return;
567 src_addr = &tmpaddr;
568 }
569
570 icmp6h.icmp6_router = router;
571 icmp6h.icmp6_solicited = solicited;
572 icmp6h.icmp6_override = override;
573
574 __ndisc_send(dev, neigh, daddr, src_addr,
575 &icmp6h, solicited_addr,
576 inc_opt ? ND_OPT_TARGET_LL_ADDR : 0);
577 }
578
579 void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
580 struct in6_addr *solicit,
581 struct in6_addr *daddr, struct in6_addr *saddr)
582 {
583 struct in6_addr addr_buf;
584 struct icmp6hdr icmp6h = {
585 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
586 };
587
588 if (saddr == NULL) {
589 if (ipv6_get_lladdr(dev, &addr_buf,
590 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
591 return;
592 saddr = &addr_buf;
593 }
594
595 __ndisc_send(dev, neigh, daddr, saddr,
596 &icmp6h, solicit,
597 !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0);
598 }
599
600 void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
601 struct in6_addr *daddr)
602 {
603 struct icmp6hdr icmp6h = {
604 .icmp6_type = NDISC_ROUTER_SOLICITATION,
605 };
606 int send_sllao = dev->addr_len;
607
608 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
609 /*
610 * According to section 2.2 of RFC 4429, we must not
611 * send router solicitations with a sllao from
612 * optimistic addresses, but we may send the solicitation
613 * if we don't include the sllao. So here we check
614 * if our address is optimistic, and if so, we
615 * supress the inclusion of the sllao.
616 */
617 if (send_sllao) {
618 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(saddr, dev, 1);
619 if (ifp) {
620 if (ifp->flags & IFA_F_OPTIMISTIC) {
621 send_sllao = 0;
622 }
623 in6_ifa_put(ifp);
624 } else {
625 send_sllao = 0;
626 }
627 }
628 #endif
629 __ndisc_send(dev, NULL, daddr, saddr,
630 &icmp6h, NULL,
631 send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0);
632 }
633
634
635 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
636 {
637 /*
638 * "The sender MUST return an ICMP
639 * destination unreachable"
640 */
641 dst_link_failure(skb);
642 kfree_skb(skb);
643 }
644
645 /* Called with locked neigh: either read or both */
646
647 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
648 {
649 struct in6_addr *saddr = NULL;
650 struct in6_addr mcaddr;
651 struct net_device *dev = neigh->dev;
652 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
653 int probes = atomic_read(&neigh->probes);
654
655 if (skb && ipv6_chk_addr(&ipv6_hdr(skb)->saddr, dev, 1))
656 saddr = &ipv6_hdr(skb)->saddr;
657
658 if ((probes -= neigh->parms->ucast_probes) < 0) {
659 if (!(neigh->nud_state & NUD_VALID)) {
660 ND_PRINTK1(KERN_DEBUG
661 "%s(): trying to ucast probe in NUD_INVALID: "
662 NIP6_FMT "\n",
663 __FUNCTION__,
664 NIP6(*target));
665 }
666 ndisc_send_ns(dev, neigh, target, target, saddr);
667 } else if ((probes -= neigh->parms->app_probes) < 0) {
668 #ifdef CONFIG_ARPD
669 neigh_app_ns(neigh);
670 #endif
671 } else {
672 addrconf_addr_solict_mult(target, &mcaddr);
673 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
674 }
675 }
676
677 static void ndisc_recv_ns(struct sk_buff *skb)
678 {
679 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
680 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
681 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
682 u8 *lladdr = NULL;
683 u32 ndoptlen = skb->tail - (skb->transport_header +
684 offsetof(struct nd_msg, opt));
685 struct ndisc_options ndopts;
686 struct net_device *dev = skb->dev;
687 struct inet6_ifaddr *ifp;
688 struct inet6_dev *idev = NULL;
689 struct neighbour *neigh;
690 struct pneigh_entry *pneigh = NULL;
691 int dad = ipv6_addr_any(saddr);
692 int inc;
693 int is_router;
694
695 if (ipv6_addr_is_multicast(&msg->target)) {
696 ND_PRINTK2(KERN_WARNING
697 "ICMPv6 NS: multicast target address");
698 return;
699 }
700
701 /*
702 * RFC2461 7.1.1:
703 * DAD has to be destined for solicited node multicast address.
704 */
705 if (dad &&
706 !(daddr->s6_addr32[0] == htonl(0xff020000) &&
707 daddr->s6_addr32[1] == htonl(0x00000000) &&
708 daddr->s6_addr32[2] == htonl(0x00000001) &&
709 daddr->s6_addr [12] == 0xff )) {
710 ND_PRINTK2(KERN_WARNING
711 "ICMPv6 NS: bad DAD packet (wrong destination)\n");
712 return;
713 }
714
715 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
716 ND_PRINTK2(KERN_WARNING
717 "ICMPv6 NS: invalid ND options\n");
718 return;
719 }
720
721 if (ndopts.nd_opts_src_lladdr) {
722 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
723 if (!lladdr) {
724 ND_PRINTK2(KERN_WARNING
725 "ICMPv6 NS: invalid link-layer address length\n");
726 return;
727 }
728
729 /* RFC2461 7.1.1:
730 * If the IP source address is the unspecified address,
731 * there MUST NOT be source link-layer address option
732 * in the message.
733 */
734 if (dad) {
735 ND_PRINTK2(KERN_WARNING
736 "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
737 return;
738 }
739 }
740
741 inc = ipv6_addr_is_multicast(daddr);
742
743 if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1)) != NULL) {
744
745 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
746 if (dad) {
747 if (dev->type == ARPHRD_IEEE802_TR) {
748 const unsigned char *sadr;
749 sadr = skb_mac_header(skb);
750 if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
751 sadr[9] == dev->dev_addr[1] &&
752 sadr[10] == dev->dev_addr[2] &&
753 sadr[11] == dev->dev_addr[3] &&
754 sadr[12] == dev->dev_addr[4] &&
755 sadr[13] == dev->dev_addr[5]) {
756 /* looped-back to us */
757 goto out;
758 }
759 }
760
761 /*
762 * We are colliding with another node
763 * who is doing DAD
764 * so fail our DAD process
765 */
766 addrconf_dad_failure(ifp);
767 return;
768 } else {
769 /*
770 * This is not a dad solicitation.
771 * If we are an optimistic node,
772 * we should respond.
773 * Otherwise, we should ignore it.
774 */
775 if (!(ifp->flags & IFA_F_OPTIMISTIC))
776 goto out;
777 }
778 }
779
780 idev = ifp->idev;
781 } else {
782 idev = in6_dev_get(dev);
783 if (!idev) {
784 /* XXX: count this drop? */
785 return;
786 }
787
788 if (ipv6_chk_acast_addr(dev, &msg->target) ||
789 (idev->cnf.forwarding &&
790 (ipv6_devconf.proxy_ndp || idev->cnf.proxy_ndp) &&
791 (pneigh = pneigh_lookup(&nd_tbl,
792 &msg->target, dev, 0)) != NULL)) {
793 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
794 skb->pkt_type != PACKET_HOST &&
795 inc != 0 &&
796 idev->nd_parms->proxy_delay != 0) {
797 /*
798 * for anycast or proxy,
799 * sender should delay its response
800 * by a random time between 0 and
801 * MAX_ANYCAST_DELAY_TIME seconds.
802 * (RFC2461) -- yoshfuji
803 */
804 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
805 if (n)
806 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
807 goto out;
808 }
809 } else
810 goto out;
811 }
812
813 is_router = !!(pneigh ? pneigh->flags & NTF_ROUTER : idev->cnf.forwarding);
814
815 if (dad) {
816 struct in6_addr maddr;
817
818 ipv6_addr_all_nodes(&maddr);
819 ndisc_send_na(dev, NULL, &maddr, &msg->target,
820 is_router, 0, (ifp != NULL), 1);
821 goto out;
822 }
823
824 if (inc)
825 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
826 else
827 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
828
829 /*
830 * update / create cache entry
831 * for the source address
832 */
833 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
834 !inc || lladdr || !dev->addr_len);
835 if (neigh)
836 neigh_update(neigh, lladdr, NUD_STALE,
837 NEIGH_UPDATE_F_WEAK_OVERRIDE|
838 NEIGH_UPDATE_F_OVERRIDE);
839 if (neigh || !dev->header_ops) {
840 ndisc_send_na(dev, neigh, saddr, &msg->target,
841 is_router,
842 1, (ifp != NULL && inc), inc);
843 if (neigh)
844 neigh_release(neigh);
845 }
846
847 out:
848 if (ifp)
849 in6_ifa_put(ifp);
850 else
851 in6_dev_put(idev);
852
853 return;
854 }
855
856 static void ndisc_recv_na(struct sk_buff *skb)
857 {
858 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
859 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
860 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
861 u8 *lladdr = NULL;
862 u32 ndoptlen = skb->tail - (skb->transport_header +
863 offsetof(struct nd_msg, opt));
864 struct ndisc_options ndopts;
865 struct net_device *dev = skb->dev;
866 struct inet6_ifaddr *ifp;
867 struct neighbour *neigh;
868
869 if (skb->len < sizeof(struct nd_msg)) {
870 ND_PRINTK2(KERN_WARNING
871 "ICMPv6 NA: packet too short\n");
872 return;
873 }
874
875 if (ipv6_addr_is_multicast(&msg->target)) {
876 ND_PRINTK2(KERN_WARNING
877 "ICMPv6 NA: target address is multicast.\n");
878 return;
879 }
880
881 if (ipv6_addr_is_multicast(daddr) &&
882 msg->icmph.icmp6_solicited) {
883 ND_PRINTK2(KERN_WARNING
884 "ICMPv6 NA: solicited NA is multicasted.\n");
885 return;
886 }
887
888 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
889 ND_PRINTK2(KERN_WARNING
890 "ICMPv6 NS: invalid ND option\n");
891 return;
892 }
893 if (ndopts.nd_opts_tgt_lladdr) {
894 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
895 if (!lladdr) {
896 ND_PRINTK2(KERN_WARNING
897 "ICMPv6 NA: invalid link-layer address length\n");
898 return;
899 }
900 }
901 if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1))) {
902 if (ifp->flags & IFA_F_TENTATIVE) {
903 addrconf_dad_failure(ifp);
904 return;
905 }
906 /* What should we make now? The advertisement
907 is invalid, but ndisc specs say nothing
908 about it. It could be misconfiguration, or
909 an smart proxy agent tries to help us :-)
910 */
911 ND_PRINTK1(KERN_WARNING
912 "ICMPv6 NA: someone advertises our address on %s!\n",
913 ifp->idev->dev->name);
914 in6_ifa_put(ifp);
915 return;
916 }
917 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
918
919 if (neigh) {
920 u8 old_flags = neigh->flags;
921
922 if (neigh->nud_state & NUD_FAILED)
923 goto out;
924
925 /*
926 * Don't update the neighbor cache entry on a proxy NA from
927 * ourselves because either the proxied node is off link or it
928 * has already sent a NA to us.
929 */
930 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
931 ipv6_devconf.forwarding && ipv6_devconf.proxy_ndp &&
932 pneigh_lookup(&nd_tbl, &msg->target, dev, 0)) {
933 /* XXX: idev->cnf.prixy_ndp */
934 goto out;
935 }
936
937 neigh_update(neigh, lladdr,
938 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
939 NEIGH_UPDATE_F_WEAK_OVERRIDE|
940 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
941 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
942 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
943
944 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
945 /*
946 * Change: router to host
947 */
948 struct rt6_info *rt;
949 rt = rt6_get_dflt_router(saddr, dev);
950 if (rt)
951 ip6_del_rt(rt);
952 }
953
954 out:
955 neigh_release(neigh);
956 }
957 }
958
959 static void ndisc_recv_rs(struct sk_buff *skb)
960 {
961 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
962 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
963 struct neighbour *neigh;
964 struct inet6_dev *idev;
965 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
966 struct ndisc_options ndopts;
967 u8 *lladdr = NULL;
968
969 if (skb->len < sizeof(*rs_msg))
970 return;
971
972 idev = in6_dev_get(skb->dev);
973 if (!idev) {
974 if (net_ratelimit())
975 ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
976 return;
977 }
978
979 /* Don't accept RS if we're not in router mode */
980 if (!idev->cnf.forwarding)
981 goto out;
982
983 /*
984 * Don't update NCE if src = ::;
985 * this implies that the source node has no ip address assigned yet.
986 */
987 if (ipv6_addr_any(saddr))
988 goto out;
989
990 /* Parse ND options */
991 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
992 if (net_ratelimit())
993 ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
994 goto out;
995 }
996
997 if (ndopts.nd_opts_src_lladdr) {
998 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
999 skb->dev);
1000 if (!lladdr)
1001 goto out;
1002 }
1003
1004 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1005 if (neigh) {
1006 neigh_update(neigh, lladdr, NUD_STALE,
1007 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1008 NEIGH_UPDATE_F_OVERRIDE|
1009 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1010 neigh_release(neigh);
1011 }
1012 out:
1013 in6_dev_put(idev);
1014 }
1015
1016 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1017 {
1018 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1019 struct sk_buff *skb;
1020 struct nlmsghdr *nlh;
1021 struct nduseroptmsg *ndmsg;
1022 int err;
1023 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1024 + (opt->nd_opt_len << 3));
1025 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1026
1027 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1028 if (skb == NULL) {
1029 err = -ENOBUFS;
1030 goto errout;
1031 }
1032
1033 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1034 if (nlh == NULL) {
1035 goto nla_put_failure;
1036 }
1037
1038 ndmsg = nlmsg_data(nlh);
1039 ndmsg->nduseropt_family = AF_INET6;
1040 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1041 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1042 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1043 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1044
1045 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1046
1047 NLA_PUT(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1048 &ipv6_hdr(ra)->saddr);
1049 nlmsg_end(skb, nlh);
1050
1051 err = rtnl_notify(skb, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
1052 if (err < 0)
1053 goto errout;
1054
1055 return;
1056
1057 nla_put_failure:
1058 nlmsg_free(skb);
1059 err = -EMSGSIZE;
1060 errout:
1061 rtnl_set_sk_err(RTNLGRP_ND_USEROPT, err);
1062 }
1063
1064 static void ndisc_router_discovery(struct sk_buff *skb)
1065 {
1066 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1067 struct neighbour *neigh = NULL;
1068 struct inet6_dev *in6_dev;
1069 struct rt6_info *rt = NULL;
1070 int lifetime;
1071 struct ndisc_options ndopts;
1072 int optlen;
1073 unsigned int pref = 0;
1074
1075 __u8 * opt = (__u8 *)(ra_msg + 1);
1076
1077 optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
1078
1079 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1080 ND_PRINTK2(KERN_WARNING
1081 "ICMPv6 RA: source address is not link-local.\n");
1082 return;
1083 }
1084 if (optlen < 0) {
1085 ND_PRINTK2(KERN_WARNING
1086 "ICMPv6 RA: packet too short\n");
1087 return;
1088 }
1089
1090 /*
1091 * set the RA_RECV flag in the interface
1092 */
1093
1094 in6_dev = in6_dev_get(skb->dev);
1095 if (in6_dev == NULL) {
1096 ND_PRINTK0(KERN_ERR
1097 "ICMPv6 RA: can't find inet6 device for %s.\n",
1098 skb->dev->name);
1099 return;
1100 }
1101 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra) {
1102 in6_dev_put(in6_dev);
1103 return;
1104 }
1105
1106 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1107 in6_dev_put(in6_dev);
1108 ND_PRINTK2(KERN_WARNING
1109 "ICMP6 RA: invalid ND options\n");
1110 return;
1111 }
1112
1113 if (in6_dev->if_flags & IF_RS_SENT) {
1114 /*
1115 * flag that an RA was received after an RS was sent
1116 * out on this interface.
1117 */
1118 in6_dev->if_flags |= IF_RA_RCVD;
1119 }
1120
1121 /*
1122 * Remember the managed/otherconf flags from most recently
1123 * received RA message (RFC 2462) -- yoshfuji
1124 */
1125 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1126 IF_RA_OTHERCONF)) |
1127 (ra_msg->icmph.icmp6_addrconf_managed ?
1128 IF_RA_MANAGED : 0) |
1129 (ra_msg->icmph.icmp6_addrconf_other ?
1130 IF_RA_OTHERCONF : 0);
1131
1132 if (!in6_dev->cnf.accept_ra_defrtr)
1133 goto skip_defrtr;
1134
1135 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1136
1137 #ifdef CONFIG_IPV6_ROUTER_PREF
1138 pref = ra_msg->icmph.icmp6_router_pref;
1139 /* 10b is handled as if it were 00b (medium) */
1140 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1141 !in6_dev->cnf.accept_ra_rtr_pref)
1142 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1143 #endif
1144
1145 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1146
1147 if (rt)
1148 neigh = rt->rt6i_nexthop;
1149
1150 if (rt && lifetime == 0) {
1151 neigh_clone(neigh);
1152 ip6_del_rt(rt);
1153 rt = NULL;
1154 }
1155
1156 if (rt == NULL && lifetime) {
1157 ND_PRINTK3(KERN_DEBUG
1158 "ICMPv6 RA: adding default router.\n");
1159
1160 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1161 if (rt == NULL) {
1162 ND_PRINTK0(KERN_ERR
1163 "ICMPv6 RA: %s() failed to add default route.\n",
1164 __FUNCTION__);
1165 in6_dev_put(in6_dev);
1166 return;
1167 }
1168
1169 neigh = rt->rt6i_nexthop;
1170 if (neigh == NULL) {
1171 ND_PRINTK0(KERN_ERR
1172 "ICMPv6 RA: %s() got default router without neighbour.\n",
1173 __FUNCTION__);
1174 dst_release(&rt->u.dst);
1175 in6_dev_put(in6_dev);
1176 return;
1177 }
1178 neigh->flags |= NTF_ROUTER;
1179 } else if (rt) {
1180 rt->rt6i_flags |= (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1181 }
1182
1183 if (rt)
1184 rt->rt6i_expires = jiffies + (HZ * lifetime);
1185
1186 if (ra_msg->icmph.icmp6_hop_limit) {
1187 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1188 if (rt)
1189 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit;
1190 }
1191
1192 skip_defrtr:
1193
1194 /*
1195 * Update Reachable Time and Retrans Timer
1196 */
1197
1198 if (in6_dev->nd_parms) {
1199 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1200
1201 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1202 rtime = (rtime*HZ)/1000;
1203 if (rtime < HZ/10)
1204 rtime = HZ/10;
1205 in6_dev->nd_parms->retrans_time = rtime;
1206 in6_dev->tstamp = jiffies;
1207 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1208 }
1209
1210 rtime = ntohl(ra_msg->reachable_time);
1211 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1212 rtime = (rtime*HZ)/1000;
1213
1214 if (rtime < HZ/10)
1215 rtime = HZ/10;
1216
1217 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1218 in6_dev->nd_parms->base_reachable_time = rtime;
1219 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1220 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1221 in6_dev->tstamp = jiffies;
1222 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1223 }
1224 }
1225 }
1226
1227 /*
1228 * Process options.
1229 */
1230
1231 if (!neigh)
1232 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1233 skb->dev, 1);
1234 if (neigh) {
1235 u8 *lladdr = NULL;
1236 if (ndopts.nd_opts_src_lladdr) {
1237 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1238 skb->dev);
1239 if (!lladdr) {
1240 ND_PRINTK2(KERN_WARNING
1241 "ICMPv6 RA: invalid link-layer address length\n");
1242 goto out;
1243 }
1244 }
1245 neigh_update(neigh, lladdr, NUD_STALE,
1246 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1247 NEIGH_UPDATE_F_OVERRIDE|
1248 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1249 NEIGH_UPDATE_F_ISROUTER);
1250 }
1251
1252 #ifdef CONFIG_IPV6_ROUTE_INFO
1253 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1254 struct nd_opt_hdr *p;
1255 for (p = ndopts.nd_opts_ri;
1256 p;
1257 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1258 if (((struct route_info *)p)->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1259 continue;
1260 rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1261 &ipv6_hdr(skb)->saddr);
1262 }
1263 }
1264 #endif
1265
1266 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1267 struct nd_opt_hdr *p;
1268 for (p = ndopts.nd_opts_pi;
1269 p;
1270 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1271 addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
1272 }
1273 }
1274
1275 if (ndopts.nd_opts_mtu) {
1276 __be32 n;
1277 u32 mtu;
1278
1279 memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1280 mtu = ntohl(n);
1281
1282 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1283 ND_PRINTK2(KERN_WARNING
1284 "ICMPv6 RA: invalid mtu: %d\n",
1285 mtu);
1286 } else if (in6_dev->cnf.mtu6 != mtu) {
1287 in6_dev->cnf.mtu6 = mtu;
1288
1289 if (rt)
1290 rt->u.dst.metrics[RTAX_MTU-1] = mtu;
1291
1292 rt6_mtu_change(skb->dev, mtu);
1293 }
1294 }
1295
1296 if (ndopts.nd_useropts) {
1297 struct nd_opt_hdr *opt;
1298 for (opt = ndopts.nd_useropts;
1299 opt;
1300 opt = ndisc_next_useropt(opt, ndopts.nd_useropts_end)) {
1301 ndisc_ra_useropt(skb, opt);
1302 }
1303 }
1304
1305 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1306 ND_PRINTK2(KERN_WARNING
1307 "ICMPv6 RA: invalid RA options");
1308 }
1309 out:
1310 if (rt)
1311 dst_release(&rt->u.dst);
1312 else if (neigh)
1313 neigh_release(neigh);
1314 in6_dev_put(in6_dev);
1315 }
1316
1317 static void ndisc_redirect_rcv(struct sk_buff *skb)
1318 {
1319 struct inet6_dev *in6_dev;
1320 struct icmp6hdr *icmph;
1321 struct in6_addr *dest;
1322 struct in6_addr *target; /* new first hop to destination */
1323 struct neighbour *neigh;
1324 int on_link = 0;
1325 struct ndisc_options ndopts;
1326 int optlen;
1327 u8 *lladdr = NULL;
1328
1329 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1330 ND_PRINTK2(KERN_WARNING
1331 "ICMPv6 Redirect: source address is not link-local.\n");
1332 return;
1333 }
1334
1335 optlen = skb->tail - skb->transport_header;
1336 optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1337
1338 if (optlen < 0) {
1339 ND_PRINTK2(KERN_WARNING
1340 "ICMPv6 Redirect: packet too short\n");
1341 return;
1342 }
1343
1344 icmph = icmp6_hdr(skb);
1345 target = (struct in6_addr *) (icmph + 1);
1346 dest = target + 1;
1347
1348 if (ipv6_addr_is_multicast(dest)) {
1349 ND_PRINTK2(KERN_WARNING
1350 "ICMPv6 Redirect: destination address is multicast.\n");
1351 return;
1352 }
1353
1354 if (ipv6_addr_equal(dest, target)) {
1355 on_link = 1;
1356 } else if (ipv6_addr_type(target) !=
1357 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1358 ND_PRINTK2(KERN_WARNING
1359 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1360 return;
1361 }
1362
1363 in6_dev = in6_dev_get(skb->dev);
1364 if (!in6_dev)
1365 return;
1366 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) {
1367 in6_dev_put(in6_dev);
1368 return;
1369 }
1370
1371 /* RFC2461 8.1:
1372 * The IP source address of the Redirect MUST be the same as the current
1373 * first-hop router for the specified ICMP Destination Address.
1374 */
1375
1376 if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1377 ND_PRINTK2(KERN_WARNING
1378 "ICMPv6 Redirect: invalid ND options\n");
1379 in6_dev_put(in6_dev);
1380 return;
1381 }
1382 if (ndopts.nd_opts_tgt_lladdr) {
1383 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1384 skb->dev);
1385 if (!lladdr) {
1386 ND_PRINTK2(KERN_WARNING
1387 "ICMPv6 Redirect: invalid link-layer address length\n");
1388 in6_dev_put(in6_dev);
1389 return;
1390 }
1391 }
1392
1393 neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1394 if (neigh) {
1395 rt6_redirect(dest, &ipv6_hdr(skb)->daddr,
1396 &ipv6_hdr(skb)->saddr, neigh, lladdr,
1397 on_link);
1398 neigh_release(neigh);
1399 }
1400 in6_dev_put(in6_dev);
1401 }
1402
1403 void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
1404 struct in6_addr *target)
1405 {
1406 struct sock *sk = ndisc_socket->sk;
1407 int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1408 struct sk_buff *buff;
1409 struct icmp6hdr *icmph;
1410 struct in6_addr saddr_buf;
1411 struct in6_addr *addrp;
1412 struct net_device *dev;
1413 struct rt6_info *rt;
1414 struct dst_entry *dst;
1415 struct inet6_dev *idev;
1416 struct flowi fl;
1417 u8 *opt;
1418 int rd_len;
1419 int err;
1420 int hlen;
1421 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1422
1423 dev = skb->dev;
1424
1425 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1426 ND_PRINTK2(KERN_WARNING
1427 "ICMPv6 Redirect: no link-local address on %s\n",
1428 dev->name);
1429 return;
1430 }
1431
1432 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1433 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1434 ND_PRINTK2(KERN_WARNING
1435 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1436 return;
1437 }
1438
1439 ndisc_flow_init(&fl, NDISC_REDIRECT, &saddr_buf, &ipv6_hdr(skb)->saddr,
1440 dev->ifindex);
1441
1442 dst = ip6_route_output(NULL, &fl);
1443 if (dst == NULL)
1444 return;
1445
1446 err = xfrm_lookup(&dst, &fl, NULL, 0);
1447 if (err)
1448 return;
1449
1450 rt = (struct rt6_info *) dst;
1451
1452 if (rt->rt6i_flags & RTF_GATEWAY) {
1453 ND_PRINTK2(KERN_WARNING
1454 "ICMPv6 Redirect: destination is not a neighbour.\n");
1455 dst_release(dst);
1456 return;
1457 }
1458 if (!xrlim_allow(dst, 1*HZ)) {
1459 dst_release(dst);
1460 return;
1461 }
1462
1463 if (dev->addr_len) {
1464 read_lock_bh(&neigh->lock);
1465 if (neigh->nud_state & NUD_VALID) {
1466 memcpy(ha_buf, neigh->ha, dev->addr_len);
1467 read_unlock_bh(&neigh->lock);
1468 ha = ha_buf;
1469 len += ndisc_opt_addr_space(dev);
1470 } else
1471 read_unlock_bh(&neigh->lock);
1472 }
1473
1474 rd_len = min_t(unsigned int,
1475 IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1476 rd_len &= ~0x7;
1477 len += rd_len;
1478
1479 buff = sock_alloc_send_skb(sk,
1480 (MAX_HEADER + sizeof(struct ipv6hdr) +
1481 len + LL_RESERVED_SPACE(dev)),
1482 1, &err);
1483 if (buff == NULL) {
1484 ND_PRINTK0(KERN_ERR
1485 "ICMPv6 Redirect: %s() failed to allocate an skb.\n",
1486 __FUNCTION__);
1487 dst_release(dst);
1488 return;
1489 }
1490
1491 hlen = 0;
1492
1493 skb_reserve(buff, LL_RESERVED_SPACE(dev));
1494 ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
1495 IPPROTO_ICMPV6, len);
1496
1497 skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
1498 skb_put(buff, len);
1499 icmph = icmp6_hdr(buff);
1500
1501 memset(icmph, 0, sizeof(struct icmp6hdr));
1502 icmph->icmp6_type = NDISC_REDIRECT;
1503
1504 /*
1505 * copy target and destination addresses
1506 */
1507
1508 addrp = (struct in6_addr *)(icmph + 1);
1509 ipv6_addr_copy(addrp, target);
1510 addrp++;
1511 ipv6_addr_copy(addrp, &ipv6_hdr(skb)->daddr);
1512
1513 opt = (u8*) (addrp + 1);
1514
1515 /*
1516 * include target_address option
1517 */
1518
1519 if (ha)
1520 opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1521 dev->addr_len, dev->type);
1522
1523 /*
1524 * build redirect option and copy skb over to the new packet.
1525 */
1526
1527 memset(opt, 0, 8);
1528 *(opt++) = ND_OPT_REDIRECT_HDR;
1529 *(opt++) = (rd_len >> 3);
1530 opt += 6;
1531
1532 memcpy(opt, ipv6_hdr(skb), rd_len - 8);
1533
1534 icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
1535 len, IPPROTO_ICMPV6,
1536 csum_partial((u8 *) icmph, len, 0));
1537
1538 buff->dst = dst;
1539 idev = in6_dev_get(dst->dev);
1540 IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
1541 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, buff, NULL, dst->dev, dst_output);
1542 if (!err) {
1543 ICMP6MSGOUT_INC_STATS(idev, NDISC_REDIRECT);
1544 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
1545 }
1546
1547 if (likely(idev != NULL))
1548 in6_dev_put(idev);
1549 }
1550
1551 static void pndisc_redo(struct sk_buff *skb)
1552 {
1553 ndisc_recv_ns(skb);
1554 kfree_skb(skb);
1555 }
1556
1557 int ndisc_rcv(struct sk_buff *skb)
1558 {
1559 struct nd_msg *msg;
1560
1561 if (!pskb_may_pull(skb, skb->len))
1562 return 0;
1563
1564 msg = (struct nd_msg *)skb_transport_header(skb);
1565
1566 __skb_push(skb, skb->data - skb_transport_header(skb));
1567
1568 if (ipv6_hdr(skb)->hop_limit != 255) {
1569 ND_PRINTK2(KERN_WARNING
1570 "ICMPv6 NDISC: invalid hop-limit: %d\n",
1571 ipv6_hdr(skb)->hop_limit);
1572 return 0;
1573 }
1574
1575 if (msg->icmph.icmp6_code != 0) {
1576 ND_PRINTK2(KERN_WARNING
1577 "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
1578 msg->icmph.icmp6_code);
1579 return 0;
1580 }
1581
1582 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1583
1584 switch (msg->icmph.icmp6_type) {
1585 case NDISC_NEIGHBOUR_SOLICITATION:
1586 ndisc_recv_ns(skb);
1587 break;
1588
1589 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1590 ndisc_recv_na(skb);
1591 break;
1592
1593 case NDISC_ROUTER_SOLICITATION:
1594 ndisc_recv_rs(skb);
1595 break;
1596
1597 case NDISC_ROUTER_ADVERTISEMENT:
1598 ndisc_router_discovery(skb);
1599 break;
1600
1601 case NDISC_REDIRECT:
1602 ndisc_redirect_rcv(skb);
1603 break;
1604 }
1605
1606 return 0;
1607 }
1608
1609 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1610 {
1611 struct net_device *dev = ptr;
1612
1613 if (dev->nd_net != &init_net)
1614 return NOTIFY_DONE;
1615
1616 switch (event) {
1617 case NETDEV_CHANGEADDR:
1618 neigh_changeaddr(&nd_tbl, dev);
1619 fib6_run_gc(~0UL);
1620 break;
1621 case NETDEV_DOWN:
1622 neigh_ifdown(&nd_tbl, dev);
1623 fib6_run_gc(~0UL);
1624 break;
1625 default:
1626 break;
1627 }
1628
1629 return NOTIFY_DONE;
1630 }
1631
1632 static struct notifier_block ndisc_netdev_notifier = {
1633 .notifier_call = ndisc_netdev_event,
1634 };
1635
1636 #ifdef CONFIG_SYSCTL
1637 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1638 const char *func, const char *dev_name)
1639 {
1640 static char warncomm[TASK_COMM_LEN];
1641 static int warned;
1642 if (strcmp(warncomm, current->comm) && warned < 5) {
1643 strcpy(warncomm, current->comm);
1644 printk(KERN_WARNING
1645 "process `%s' is using deprecated sysctl (%s) "
1646 "net.ipv6.neigh.%s.%s; "
1647 "Use net.ipv6.neigh.%s.%s_ms "
1648 "instead.\n",
1649 warncomm, func,
1650 dev_name, ctl->procname,
1651 dev_name, ctl->procname);
1652 warned++;
1653 }
1654 }
1655
1656 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, struct file * filp, void __user *buffer, size_t *lenp, loff_t *ppos)
1657 {
1658 struct net_device *dev = ctl->extra1;
1659 struct inet6_dev *idev;
1660 int ret;
1661
1662 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1663 (strcmp(ctl->procname, "base_reachable_time") == 0))
1664 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1665
1666 if (strcmp(ctl->procname, "retrans_time") == 0)
1667 ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1668
1669 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1670 ret = proc_dointvec_jiffies(ctl, write,
1671 filp, buffer, lenp, ppos);
1672
1673 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1674 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1675 ret = proc_dointvec_ms_jiffies(ctl, write,
1676 filp, buffer, lenp, ppos);
1677 else
1678 ret = -1;
1679
1680 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1681 if (ctl->data == &idev->nd_parms->base_reachable_time)
1682 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1683 idev->tstamp = jiffies;
1684 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1685 in6_dev_put(idev);
1686 }
1687 return ret;
1688 }
1689
1690 static int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl, int __user *name,
1691 int nlen, void __user *oldval,
1692 size_t __user *oldlenp,
1693 void __user *newval, size_t newlen)
1694 {
1695 struct net_device *dev = ctl->extra1;
1696 struct inet6_dev *idev;
1697 int ret;
1698
1699 if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
1700 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
1701 ndisc_warn_deprecated_sysctl(ctl, "procfs", dev ? dev->name : "default");
1702
1703 switch (ctl->ctl_name) {
1704 case NET_NEIGH_REACHABLE_TIME:
1705 ret = sysctl_jiffies(ctl, name, nlen,
1706 oldval, oldlenp, newval, newlen);
1707 break;
1708 case NET_NEIGH_RETRANS_TIME_MS:
1709 case NET_NEIGH_REACHABLE_TIME_MS:
1710 ret = sysctl_ms_jiffies(ctl, name, nlen,
1711 oldval, oldlenp, newval, newlen);
1712 break;
1713 default:
1714 ret = 0;
1715 }
1716
1717 if (newval && newlen && ret > 0 &&
1718 dev && (idev = in6_dev_get(dev)) != NULL) {
1719 if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
1720 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
1721 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1722 idev->tstamp = jiffies;
1723 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1724 in6_dev_put(idev);
1725 }
1726
1727 return ret;
1728 }
1729
1730 #endif
1731
1732 int __init ndisc_init(struct net_proto_family *ops)
1733 {
1734 struct ipv6_pinfo *np;
1735 struct sock *sk;
1736 int err;
1737
1738 err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6, &ndisc_socket);
1739 if (err < 0) {
1740 ND_PRINTK0(KERN_ERR
1741 "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n",
1742 err);
1743 ndisc_socket = NULL; /* For safety. */
1744 return err;
1745 }
1746
1747 sk = ndisc_socket->sk;
1748 np = inet6_sk(sk);
1749 sk->sk_allocation = GFP_ATOMIC;
1750 np->hop_limit = 255;
1751 /* Do not loopback ndisc messages */
1752 np->mc_loop = 0;
1753 sk->sk_prot->unhash(sk);
1754
1755 /*
1756 * Initialize the neighbour table
1757 */
1758
1759 neigh_table_init(&nd_tbl);
1760
1761 #ifdef CONFIG_SYSCTL
1762 neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH,
1763 "ipv6",
1764 &ndisc_ifinfo_sysctl_change,
1765 &ndisc_ifinfo_sysctl_strategy);
1766 #endif
1767
1768 register_netdevice_notifier(&ndisc_netdev_notifier);
1769 return 0;
1770 }
1771
1772 void ndisc_cleanup(void)
1773 {
1774 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1775 #ifdef CONFIG_SYSCTL
1776 neigh_sysctl_unregister(&nd_tbl.parms);
1777 #endif
1778 neigh_table_clear(&nd_tbl);
1779 sock_release(ndisc_socket);
1780 ndisc_socket = NULL; /* For safety. */
1781 }
Stable & featurefull patchset based on Linus's git branch