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[IPV6] net/ipv6/ndisc.c: remove unused variable
[linux-2.6/mini2440.git] / net / ipv6 / ndisc.c
blob51557c27a0cdfc8e5d65337bf12ae0a4cf041da7
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, dev->broadcast, 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_INET_LOCAL_OUT, skb, NULL, dst->dev,
537 dst_output);
538 if (!err) {
539 ICMP6MSGOUT_INC_STATS(idev, type);
540 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
541 }
542
543 if (likely(idev != NULL))
544 in6_dev_put(idev);
545 }
546
547 static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
548 struct in6_addr *daddr, struct in6_addr *solicited_addr,
549 int router, int solicited, int override, int inc_opt)
550 {
551 struct in6_addr tmpaddr;
552 struct inet6_ifaddr *ifp;
553 struct in6_addr *src_addr;
554 struct icmp6hdr icmp6h = {
555 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
556 };
557
558 /* for anycast or proxy, solicited_addr != src_addr */
559 ifp = ipv6_get_ifaddr(&init_net, solicited_addr, dev, 1);
560 if (ifp) {
561 src_addr = solicited_addr;
562 if (ifp->flags & IFA_F_OPTIMISTIC)
563 override = 0;
564 in6_ifa_put(ifp);
565 } else {
566 if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
567 return;
568 src_addr = &tmpaddr;
569 }
570
571 icmp6h.icmp6_router = router;
572 icmp6h.icmp6_solicited = solicited;
573 icmp6h.icmp6_override = override;
574
575 __ndisc_send(dev, neigh, daddr, src_addr,
576 &icmp6h, solicited_addr,
577 inc_opt ? ND_OPT_TARGET_LL_ADDR : 0);
578 }
579
580 void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
581 struct in6_addr *solicit,
582 struct in6_addr *daddr, struct in6_addr *saddr)
583 {
584 struct in6_addr addr_buf;
585 struct icmp6hdr icmp6h = {
586 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
587 };
588
589 if (saddr == NULL) {
590 if (ipv6_get_lladdr(dev, &addr_buf,
591 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
592 return;
593 saddr = &addr_buf;
594 }
595
596 __ndisc_send(dev, neigh, daddr, saddr,
597 &icmp6h, solicit,
598 !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0);
599 }
600
601 void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
602 struct in6_addr *daddr)
603 {
604 struct icmp6hdr icmp6h = {
605 .icmp6_type = NDISC_ROUTER_SOLICITATION,
606 };
607 int send_sllao = dev->addr_len;
608
609 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
610 /*
611 * According to section 2.2 of RFC 4429, we must not
612 * send router solicitations with a sllao from
613 * optimistic addresses, but we may send the solicitation
614 * if we don't include the sllao. So here we check
615 * if our address is optimistic, and if so, we
616 * suppress the inclusion of the sllao.
617 */
618 if (send_sllao) {
619 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(&init_net, saddr,
620 dev, 1);
621 if (ifp) {
622 if (ifp->flags & IFA_F_OPTIMISTIC) {
623 send_sllao = 0;
624 }
625 in6_ifa_put(ifp);
626 } else {
627 send_sllao = 0;
628 }
629 }
630 #endif
631 __ndisc_send(dev, NULL, daddr, saddr,
632 &icmp6h, NULL,
633 send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0);
634 }
635
636
637 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
638 {
639 /*
640 * "The sender MUST return an ICMP
641 * destination unreachable"
642 */
643 dst_link_failure(skb);
644 kfree_skb(skb);
645 }
646
647 /* Called with locked neigh: either read or both */
648
649 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
650 {
651 struct in6_addr *saddr = NULL;
652 struct in6_addr mcaddr;
653 struct net_device *dev = neigh->dev;
654 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
655 int probes = atomic_read(&neigh->probes);
656
657 if (skb && ipv6_chk_addr(&init_net, &ipv6_hdr(skb)->saddr, dev, 1))
658 saddr = &ipv6_hdr(skb)->saddr;
659
660 if ((probes -= neigh->parms->ucast_probes) < 0) {
661 if (!(neigh->nud_state & NUD_VALID)) {
662 ND_PRINTK1(KERN_DEBUG
663 "%s(): trying to ucast probe in NUD_INVALID: "
664 NIP6_FMT "\n",
665 __FUNCTION__,
666 NIP6(*target));
667 }
668 ndisc_send_ns(dev, neigh, target, target, saddr);
669 } else if ((probes -= neigh->parms->app_probes) < 0) {
670 #ifdef CONFIG_ARPD
671 neigh_app_ns(neigh);
672 #endif
673 } else {
674 addrconf_addr_solict_mult(target, &mcaddr);
675 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
676 }
677 }
678
679 static void ndisc_recv_ns(struct sk_buff *skb)
680 {
681 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
682 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
683 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
684 u8 *lladdr = NULL;
685 u32 ndoptlen = skb->tail - (skb->transport_header +
686 offsetof(struct nd_msg, opt));
687 struct ndisc_options ndopts;
688 struct net_device *dev = skb->dev;
689 struct inet6_ifaddr *ifp;
690 struct inet6_dev *idev = NULL;
691 struct neighbour *neigh;
692 struct pneigh_entry *pneigh = NULL;
693 int dad = ipv6_addr_any(saddr);
694 int inc;
695 int is_router;
696
697 if (ipv6_addr_is_multicast(&msg->target)) {
698 ND_PRINTK2(KERN_WARNING
699 "ICMPv6 NS: multicast target address");
700 return;
701 }
702
703 /*
704 * RFC2461 7.1.1:
705 * DAD has to be destined for solicited node multicast address.
706 */
707 if (dad &&
708 !(daddr->s6_addr32[0] == htonl(0xff020000) &&
709 daddr->s6_addr32[1] == htonl(0x00000000) &&
710 daddr->s6_addr32[2] == htonl(0x00000001) &&
711 daddr->s6_addr [12] == 0xff )) {
712 ND_PRINTK2(KERN_WARNING
713 "ICMPv6 NS: bad DAD packet (wrong destination)\n");
714 return;
715 }
716
717 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
718 ND_PRINTK2(KERN_WARNING
719 "ICMPv6 NS: invalid ND options\n");
720 return;
721 }
722
723 if (ndopts.nd_opts_src_lladdr) {
724 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
725 if (!lladdr) {
726 ND_PRINTK2(KERN_WARNING
727 "ICMPv6 NS: invalid link-layer address length\n");
728 return;
729 }
730
731 /* RFC2461 7.1.1:
732 * If the IP source address is the unspecified address,
733 * there MUST NOT be source link-layer address option
734 * in the message.
735 */
736 if (dad) {
737 ND_PRINTK2(KERN_WARNING
738 "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
739 return;
740 }
741 }
742
743 inc = ipv6_addr_is_multicast(daddr);
744
745 if ((ifp = ipv6_get_ifaddr(&init_net, &msg->target, dev, 1)) != NULL) {
746
747 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
748 if (dad) {
749 if (dev->type == ARPHRD_IEEE802_TR) {
750 const unsigned char *sadr;
751 sadr = skb_mac_header(skb);
752 if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
753 sadr[9] == dev->dev_addr[1] &&
754 sadr[10] == dev->dev_addr[2] &&
755 sadr[11] == dev->dev_addr[3] &&
756 sadr[12] == dev->dev_addr[4] &&
757 sadr[13] == dev->dev_addr[5]) {
758 /* looped-back to us */
759 goto out;
760 }
761 }
762
763 /*
764 * We are colliding with another node
765 * who is doing DAD
766 * so fail our DAD process
767 */
768 addrconf_dad_failure(ifp);
769 return;
770 } else {
771 /*
772 * This is not a dad solicitation.
773 * If we are an optimistic node,
774 * we should respond.
775 * Otherwise, we should ignore it.
776 */
777 if (!(ifp->flags & IFA_F_OPTIMISTIC))
778 goto out;
779 }
780 }
781
782 idev = ifp->idev;
783 } else {
784 idev = in6_dev_get(dev);
785 if (!idev) {
786 /* XXX: count this drop? */
787 return;
788 }
789
790 if (ipv6_chk_acast_addr(dev, &msg->target) ||
791 (idev->cnf.forwarding &&
792 (ipv6_devconf.proxy_ndp || idev->cnf.proxy_ndp) &&
793 (pneigh = pneigh_lookup(&nd_tbl, &init_net,
794 &msg->target, dev, 0)) != NULL)) {
795 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
796 skb->pkt_type != PACKET_HOST &&
797 inc != 0 &&
798 idev->nd_parms->proxy_delay != 0) {
799 /*
800 * for anycast or proxy,
801 * sender should delay its response
802 * by a random time between 0 and
803 * MAX_ANYCAST_DELAY_TIME seconds.
804 * (RFC2461) -- yoshfuji
805 */
806 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
807 if (n)
808 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
809 goto out;
810 }
811 } else
812 goto out;
813 }
814
815 is_router = !!(pneigh ? pneigh->flags & NTF_ROUTER : idev->cnf.forwarding);
816
817 if (dad) {
818 struct in6_addr maddr;
819
820 ipv6_addr_all_nodes(&maddr);
821 ndisc_send_na(dev, NULL, &maddr, &msg->target,
822 is_router, 0, (ifp != NULL), 1);
823 goto out;
824 }
825
826 if (inc)
827 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
828 else
829 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
830
831 /*
832 * update / create cache entry
833 * for the source address
834 */
835 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
836 !inc || lladdr || !dev->addr_len);
837 if (neigh)
838 neigh_update(neigh, lladdr, NUD_STALE,
839 NEIGH_UPDATE_F_WEAK_OVERRIDE|
840 NEIGH_UPDATE_F_OVERRIDE);
841 if (neigh || !dev->header_ops) {
842 ndisc_send_na(dev, neigh, saddr, &msg->target,
843 is_router,
844 1, (ifp != NULL && inc), inc);
845 if (neigh)
846 neigh_release(neigh);
847 }
848
849 out:
850 if (ifp)
851 in6_ifa_put(ifp);
852 else
853 in6_dev_put(idev);
854
855 return;
856 }
857
858 static void ndisc_recv_na(struct sk_buff *skb)
859 {
860 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
861 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
862 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
863 u8 *lladdr = NULL;
864 u32 ndoptlen = skb->tail - (skb->transport_header +
865 offsetof(struct nd_msg, opt));
866 struct ndisc_options ndopts;
867 struct net_device *dev = skb->dev;
868 struct inet6_ifaddr *ifp;
869 struct neighbour *neigh;
870
871 if (skb->len < sizeof(struct nd_msg)) {
872 ND_PRINTK2(KERN_WARNING
873 "ICMPv6 NA: packet too short\n");
874 return;
875 }
876
877 if (ipv6_addr_is_multicast(&msg->target)) {
878 ND_PRINTK2(KERN_WARNING
879 "ICMPv6 NA: target address is multicast.\n");
880 return;
881 }
882
883 if (ipv6_addr_is_multicast(daddr) &&
884 msg->icmph.icmp6_solicited) {
885 ND_PRINTK2(KERN_WARNING
886 "ICMPv6 NA: solicited NA is multicasted.\n");
887 return;
888 }
889
890 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
891 ND_PRINTK2(KERN_WARNING
892 "ICMPv6 NS: invalid ND option\n");
893 return;
894 }
895 if (ndopts.nd_opts_tgt_lladdr) {
896 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
897 if (!lladdr) {
898 ND_PRINTK2(KERN_WARNING
899 "ICMPv6 NA: invalid link-layer address length\n");
900 return;
901 }
902 }
903 if ((ifp = ipv6_get_ifaddr(&init_net, &msg->target, dev, 1))) {
904 if (ifp->flags & IFA_F_TENTATIVE) {
905 addrconf_dad_failure(ifp);
906 return;
907 }
908 /* What should we make now? The advertisement
909 is invalid, but ndisc specs say nothing
910 about it. It could be misconfiguration, or
911 an smart proxy agent tries to help us :-)
912 */
913 ND_PRINTK1(KERN_WARNING
914 "ICMPv6 NA: someone advertises our address on %s!\n",
915 ifp->idev->dev->name);
916 in6_ifa_put(ifp);
917 return;
918 }
919 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
920
921 if (neigh) {
922 u8 old_flags = neigh->flags;
923
924 if (neigh->nud_state & NUD_FAILED)
925 goto out;
926
927 /*
928 * Don't update the neighbor cache entry on a proxy NA from
929 * ourselves because either the proxied node is off link or it
930 * has already sent a NA to us.
931 */
932 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
933 ipv6_devconf.forwarding && ipv6_devconf.proxy_ndp &&
934 pneigh_lookup(&nd_tbl, &init_net, &msg->target, dev, 0)) {
935 /* XXX: idev->cnf.prixy_ndp */
936 goto out;
937 }
938
939 neigh_update(neigh, lladdr,
940 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
941 NEIGH_UPDATE_F_WEAK_OVERRIDE|
942 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
943 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
944 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
945
946 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
947 /*
948 * Change: router to host
949 */
950 struct rt6_info *rt;
951 rt = rt6_get_dflt_router(saddr, dev);
952 if (rt)
953 ip6_del_rt(rt);
954 }
955
956 out:
957 neigh_release(neigh);
958 }
959 }
960
961 static void ndisc_recv_rs(struct sk_buff *skb)
962 {
963 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
964 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
965 struct neighbour *neigh;
966 struct inet6_dev *idev;
967 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
968 struct ndisc_options ndopts;
969 u8 *lladdr = NULL;
970
971 if (skb->len < sizeof(*rs_msg))
972 return;
973
974 idev = in6_dev_get(skb->dev);
975 if (!idev) {
976 if (net_ratelimit())
977 ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
978 return;
979 }
980
981 /* Don't accept RS if we're not in router mode */
982 if (!idev->cnf.forwarding)
983 goto out;
984
985 /*
986 * Don't update NCE if src = ::;
987 * this implies that the source node has no ip address assigned yet.
988 */
989 if (ipv6_addr_any(saddr))
990 goto out;
991
992 /* Parse ND options */
993 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
994 if (net_ratelimit())
995 ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
996 goto out;
997 }
998
999 if (ndopts.nd_opts_src_lladdr) {
1000 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1001 skb->dev);
1002 if (!lladdr)
1003 goto out;
1004 }
1005
1006 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
1007 if (neigh) {
1008 neigh_update(neigh, lladdr, NUD_STALE,
1009 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1010 NEIGH_UPDATE_F_OVERRIDE|
1011 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
1012 neigh_release(neigh);
1013 }
1014 out:
1015 in6_dev_put(idev);
1016 }
1017
1018 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1019 {
1020 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1021 struct sk_buff *skb;
1022 struct nlmsghdr *nlh;
1023 struct nduseroptmsg *ndmsg;
1024 int err;
1025 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1026 + (opt->nd_opt_len << 3));
1027 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1028
1029 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1030 if (skb == NULL) {
1031 err = -ENOBUFS;
1032 goto errout;
1033 }
1034
1035 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1036 if (nlh == NULL) {
1037 goto nla_put_failure;
1038 }
1039
1040 ndmsg = nlmsg_data(nlh);
1041 ndmsg->nduseropt_family = AF_INET6;
1042 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1043 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1044 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1045 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1046
1047 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1048
1049 NLA_PUT(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1050 &ipv6_hdr(ra)->saddr);
1051 nlmsg_end(skb, nlh);
1052
1053 err = rtnl_notify(skb, &init_net, 0, RTNLGRP_ND_USEROPT, NULL,
1054 GFP_ATOMIC);
1055 if (err < 0)
1056 goto errout;
1057
1058 return;
1059
1060 nla_put_failure:
1061 nlmsg_free(skb);
1062 err = -EMSGSIZE;
1063 errout:
1064 rtnl_set_sk_err(&init_net, RTNLGRP_ND_USEROPT, err);
1065 }
1066
1067 static void ndisc_router_discovery(struct sk_buff *skb)
1068 {
1069 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1070 struct neighbour *neigh = NULL;
1071 struct inet6_dev *in6_dev;
1072 struct rt6_info *rt = NULL;
1073 int lifetime;
1074 struct ndisc_options ndopts;
1075 int optlen;
1076 unsigned int pref = 0;
1077
1078 __u8 * opt = (__u8 *)(ra_msg + 1);
1079
1080 optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
1081
1082 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1083 ND_PRINTK2(KERN_WARNING
1084 "ICMPv6 RA: source address is not link-local.\n");
1085 return;
1086 }
1087 if (optlen < 0) {
1088 ND_PRINTK2(KERN_WARNING
1089 "ICMPv6 RA: packet too short\n");
1090 return;
1091 }
1092
1093 /*
1094 * set the RA_RECV flag in the interface
1095 */
1096
1097 in6_dev = in6_dev_get(skb->dev);
1098 if (in6_dev == NULL) {
1099 ND_PRINTK0(KERN_ERR
1100 "ICMPv6 RA: can't find inet6 device for %s.\n",
1101 skb->dev->name);
1102 return;
1103 }
1104 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra) {
1105 in6_dev_put(in6_dev);
1106 return;
1107 }
1108
1109 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1110 in6_dev_put(in6_dev);
1111 ND_PRINTK2(KERN_WARNING
1112 "ICMP6 RA: invalid ND options\n");
1113 return;
1114 }
1115
1116 if (in6_dev->if_flags & IF_RS_SENT) {
1117 /*
1118 * flag that an RA was received after an RS was sent
1119 * out on this interface.
1120 */
1121 in6_dev->if_flags |= IF_RA_RCVD;
1122 }
1123
1124 /*
1125 * Remember the managed/otherconf flags from most recently
1126 * received RA message (RFC 2462) -- yoshfuji
1127 */
1128 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1129 IF_RA_OTHERCONF)) |
1130 (ra_msg->icmph.icmp6_addrconf_managed ?
1131 IF_RA_MANAGED : 0) |
1132 (ra_msg->icmph.icmp6_addrconf_other ?
1133 IF_RA_OTHERCONF : 0);
1134
1135 if (!in6_dev->cnf.accept_ra_defrtr)
1136 goto skip_defrtr;
1137
1138 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1139
1140 #ifdef CONFIG_IPV6_ROUTER_PREF
1141 pref = ra_msg->icmph.icmp6_router_pref;
1142 /* 10b is handled as if it were 00b (medium) */
1143 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1144 !in6_dev->cnf.accept_ra_rtr_pref)
1145 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1146 #endif
1147
1148 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1149
1150 if (rt)
1151 neigh = rt->rt6i_nexthop;
1152
1153 if (rt && lifetime == 0) {
1154 neigh_clone(neigh);
1155 ip6_del_rt(rt);
1156 rt = NULL;
1157 }
1158
1159 if (rt == NULL && lifetime) {
1160 ND_PRINTK3(KERN_DEBUG
1161 "ICMPv6 RA: adding default router.\n");
1162
1163 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1164 if (rt == NULL) {
1165 ND_PRINTK0(KERN_ERR
1166 "ICMPv6 RA: %s() failed to add default route.\n",
1167 __FUNCTION__);
1168 in6_dev_put(in6_dev);
1169 return;
1170 }
1171
1172 neigh = rt->rt6i_nexthop;
1173 if (neigh == NULL) {
1174 ND_PRINTK0(KERN_ERR
1175 "ICMPv6 RA: %s() got default router without neighbour.\n",
1176 __FUNCTION__);
1177 dst_release(&rt->u.dst);
1178 in6_dev_put(in6_dev);
1179 return;
1180 }
1181 neigh->flags |= NTF_ROUTER;
1182 } else if (rt) {
1183 rt->rt6i_flags |= (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1184 }
1185
1186 if (rt)
1187 rt->rt6i_expires = jiffies + (HZ * lifetime);
1188
1189 if (ra_msg->icmph.icmp6_hop_limit) {
1190 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1191 if (rt)
1192 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit;
1193 }
1194
1195 skip_defrtr:
1196
1197 /*
1198 * Update Reachable Time and Retrans Timer
1199 */
1200
1201 if (in6_dev->nd_parms) {
1202 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1203
1204 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1205 rtime = (rtime*HZ)/1000;
1206 if (rtime < HZ/10)
1207 rtime = HZ/10;
1208 in6_dev->nd_parms->retrans_time = rtime;
1209 in6_dev->tstamp = jiffies;
1210 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1211 }
1212
1213 rtime = ntohl(ra_msg->reachable_time);
1214 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1215 rtime = (rtime*HZ)/1000;
1216
1217 if (rtime < HZ/10)
1218 rtime = HZ/10;
1219
1220 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1221 in6_dev->nd_parms->base_reachable_time = rtime;
1222 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1223 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1224 in6_dev->tstamp = jiffies;
1225 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1226 }
1227 }
1228 }
1229
1230 /*
1231 * Process options.
1232 */
1233
1234 if (!neigh)
1235 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1236 skb->dev, 1);
1237 if (neigh) {
1238 u8 *lladdr = NULL;
1239 if (ndopts.nd_opts_src_lladdr) {
1240 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1241 skb->dev);
1242 if (!lladdr) {
1243 ND_PRINTK2(KERN_WARNING
1244 "ICMPv6 RA: invalid link-layer address length\n");
1245 goto out;
1246 }
1247 }
1248 neigh_update(neigh, lladdr, NUD_STALE,
1249 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1250 NEIGH_UPDATE_F_OVERRIDE|
1251 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1252 NEIGH_UPDATE_F_ISROUTER);
1253 }
1254
1255 #ifdef CONFIG_IPV6_ROUTE_INFO
1256 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1257 struct nd_opt_hdr *p;
1258 for (p = ndopts.nd_opts_ri;
1259 p;
1260 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1261 if (((struct route_info *)p)->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1262 continue;
1263 rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1264 &ipv6_hdr(skb)->saddr);
1265 }
1266 }
1267 #endif
1268
1269 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1270 struct nd_opt_hdr *p;
1271 for (p = ndopts.nd_opts_pi;
1272 p;
1273 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1274 addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
1275 }
1276 }
1277
1278 if (ndopts.nd_opts_mtu) {
1279 __be32 n;
1280 u32 mtu;
1281
1282 memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1283 mtu = ntohl(n);
1284
1285 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1286 ND_PRINTK2(KERN_WARNING
1287 "ICMPv6 RA: invalid mtu: %d\n",
1288 mtu);
1289 } else if (in6_dev->cnf.mtu6 != mtu) {
1290 in6_dev->cnf.mtu6 = mtu;
1291
1292 if (rt)
1293 rt->u.dst.metrics[RTAX_MTU-1] = mtu;
1294
1295 rt6_mtu_change(skb->dev, mtu);
1296 }
1297 }
1298
1299 if (ndopts.nd_useropts) {
1300 struct nd_opt_hdr *p;
1301 for (p = ndopts.nd_useropts;
1302 p;
1303 p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
1304 ndisc_ra_useropt(skb, p);
1305 }
1306 }
1307
1308 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1309 ND_PRINTK2(KERN_WARNING
1310 "ICMPv6 RA: invalid RA options");
1311 }
1312 out:
1313 if (rt)
1314 dst_release(&rt->u.dst);
1315 else if (neigh)
1316 neigh_release(neigh);
1317 in6_dev_put(in6_dev);
1318 }
1319
1320 static void ndisc_redirect_rcv(struct sk_buff *skb)
1321 {
1322 struct inet6_dev *in6_dev;
1323 struct icmp6hdr *icmph;
1324 struct in6_addr *dest;
1325 struct in6_addr *target; /* new first hop to destination */
1326 struct neighbour *neigh;
1327 int on_link = 0;
1328 struct ndisc_options ndopts;
1329 int optlen;
1330 u8 *lladdr = NULL;
1331
1332 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1333 ND_PRINTK2(KERN_WARNING
1334 "ICMPv6 Redirect: source address is not link-local.\n");
1335 return;
1336 }
1337
1338 optlen = skb->tail - skb->transport_header;
1339 optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1340
1341 if (optlen < 0) {
1342 ND_PRINTK2(KERN_WARNING
1343 "ICMPv6 Redirect: packet too short\n");
1344 return;
1345 }
1346
1347 icmph = icmp6_hdr(skb);
1348 target = (struct in6_addr *) (icmph + 1);
1349 dest = target + 1;
1350
1351 if (ipv6_addr_is_multicast(dest)) {
1352 ND_PRINTK2(KERN_WARNING
1353 "ICMPv6 Redirect: destination address is multicast.\n");
1354 return;
1355 }
1356
1357 if (ipv6_addr_equal(dest, target)) {
1358 on_link = 1;
1359 } else if (ipv6_addr_type(target) !=
1360 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1361 ND_PRINTK2(KERN_WARNING
1362 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1363 return;
1364 }
1365
1366 in6_dev = in6_dev_get(skb->dev);
1367 if (!in6_dev)
1368 return;
1369 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) {
1370 in6_dev_put(in6_dev);
1371 return;
1372 }
1373
1374 /* RFC2461 8.1:
1375 * The IP source address of the Redirect MUST be the same as the current
1376 * first-hop router for the specified ICMP Destination Address.
1377 */
1378
1379 if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1380 ND_PRINTK2(KERN_WARNING
1381 "ICMPv6 Redirect: invalid ND options\n");
1382 in6_dev_put(in6_dev);
1383 return;
1384 }
1385 if (ndopts.nd_opts_tgt_lladdr) {
1386 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1387 skb->dev);
1388 if (!lladdr) {
1389 ND_PRINTK2(KERN_WARNING
1390 "ICMPv6 Redirect: invalid link-layer address length\n");
1391 in6_dev_put(in6_dev);
1392 return;
1393 }
1394 }
1395
1396 neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1397 if (neigh) {
1398 rt6_redirect(dest, &ipv6_hdr(skb)->daddr,
1399 &ipv6_hdr(skb)->saddr, neigh, lladdr,
1400 on_link);
1401 neigh_release(neigh);
1402 }
1403 in6_dev_put(in6_dev);
1404 }
1405
1406 void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
1407 struct in6_addr *target)
1408 {
1409 struct sock *sk = ndisc_socket->sk;
1410 int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1411 struct sk_buff *buff;
1412 struct icmp6hdr *icmph;
1413 struct in6_addr saddr_buf;
1414 struct in6_addr *addrp;
1415 struct net_device *dev;
1416 struct rt6_info *rt;
1417 struct dst_entry *dst;
1418 struct inet6_dev *idev;
1419 struct flowi fl;
1420 u8 *opt;
1421 int rd_len;
1422 int err;
1423 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1424
1425 dev = skb->dev;
1426
1427 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1428 ND_PRINTK2(KERN_WARNING
1429 "ICMPv6 Redirect: no link-local address on %s\n",
1430 dev->name);
1431 return;
1432 }
1433
1434 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1435 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1436 ND_PRINTK2(KERN_WARNING
1437 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1438 return;
1439 }
1440
1441 ndisc_flow_init(&fl, NDISC_REDIRECT, &saddr_buf, &ipv6_hdr(skb)->saddr,
1442 dev->ifindex);
1443
1444 dst = ip6_route_output(NULL, &fl);
1445 if (dst == NULL)
1446 return;
1447
1448 err = xfrm_lookup(&dst, &fl, NULL, 0);
1449 if (err)
1450 return;
1451
1452 rt = (struct rt6_info *) dst;
1453
1454 if (rt->rt6i_flags & RTF_GATEWAY) {
1455 ND_PRINTK2(KERN_WARNING
1456 "ICMPv6 Redirect: destination is not a neighbour.\n");
1457 dst_release(dst);
1458 return;
1459 }
1460 if (!xrlim_allow(dst, 1*HZ)) {
1461 dst_release(dst);
1462 return;
1463 }
1464
1465 if (dev->addr_len) {
1466 read_lock_bh(&neigh->lock);
1467 if (neigh->nud_state & NUD_VALID) {
1468 memcpy(ha_buf, neigh->ha, dev->addr_len);
1469 read_unlock_bh(&neigh->lock);
1470 ha = ha_buf;
1471 len += ndisc_opt_addr_space(dev);
1472 } else
1473 read_unlock_bh(&neigh->lock);
1474 }
1475
1476 rd_len = min_t(unsigned int,
1477 IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1478 rd_len &= ~0x7;
1479 len += rd_len;
1480
1481 buff = sock_alloc_send_skb(sk,
1482 (MAX_HEADER + sizeof(struct ipv6hdr) +
1483 len + LL_RESERVED_SPACE(dev)),
1484 1, &err);
1485 if (buff == NULL) {
1486 ND_PRINTK0(KERN_ERR
1487 "ICMPv6 Redirect: %s() failed to allocate an skb.\n",
1488 __FUNCTION__);
1489 dst_release(dst);
1490 return;
1491 }
1492
1493
1494 skb_reserve(buff, LL_RESERVED_SPACE(dev));
1495 ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
1496 IPPROTO_ICMPV6, len);
1497
1498 skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
1499 skb_put(buff, len);
1500 icmph = icmp6_hdr(buff);
1501
1502 memset(icmph, 0, sizeof(struct icmp6hdr));
1503 icmph->icmp6_type = NDISC_REDIRECT;
1504
1505 /*
1506 * copy target and destination addresses
1507 */
1508
1509 addrp = (struct in6_addr *)(icmph + 1);
1510 ipv6_addr_copy(addrp, target);
1511 addrp++;
1512 ipv6_addr_copy(addrp, &ipv6_hdr(skb)->daddr);
1513
1514 opt = (u8*) (addrp + 1);
1515
1516 /*
1517 * include target_address option
1518 */
1519
1520 if (ha)
1521 opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1522 dev->addr_len, dev->type);
1523
1524 /*
1525 * build redirect option and copy skb over to the new packet.
1526 */
1527
1528 memset(opt, 0, 8);
1529 *(opt++) = ND_OPT_REDIRECT_HDR;
1530 *(opt++) = (rd_len >> 3);
1531 opt += 6;
1532
1533 memcpy(opt, ipv6_hdr(skb), rd_len - 8);
1534
1535 icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
1536 len, IPPROTO_ICMPV6,
1537 csum_partial((u8 *) icmph, len, 0));
1538
1539 buff->dst = dst;
1540 idev = in6_dev_get(dst->dev);
1541 IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
1542 err = NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, buff, NULL, dst->dev,
1543 dst_output);
1544 if (!err) {
1545 ICMP6MSGOUT_INC_STATS(idev, NDISC_REDIRECT);
1546 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
1547 }
1548
1549 if (likely(idev != NULL))
1550 in6_dev_put(idev);
1551 }
1552
1553 static void pndisc_redo(struct sk_buff *skb)
1554 {
1555 ndisc_recv_ns(skb);
1556 kfree_skb(skb);
1557 }
1558
1559 int ndisc_rcv(struct sk_buff *skb)
1560 {
1561 struct nd_msg *msg;
1562
1563 if (!pskb_may_pull(skb, skb->len))
1564 return 0;
1565
1566 msg = (struct nd_msg *)skb_transport_header(skb);
1567
1568 __skb_push(skb, skb->data - skb_transport_header(skb));
1569
1570 if (ipv6_hdr(skb)->hop_limit != 255) {
1571 ND_PRINTK2(KERN_WARNING
1572 "ICMPv6 NDISC: invalid hop-limit: %d\n",
1573 ipv6_hdr(skb)->hop_limit);
1574 return 0;
1575 }
1576
1577 if (msg->icmph.icmp6_code != 0) {
1578 ND_PRINTK2(KERN_WARNING
1579 "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
1580 msg->icmph.icmp6_code);
1581 return 0;
1582 }
1583
1584 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1585
1586 switch (msg->icmph.icmp6_type) {
1587 case NDISC_NEIGHBOUR_SOLICITATION:
1588 ndisc_recv_ns(skb);
1589 break;
1590
1591 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1592 ndisc_recv_na(skb);
1593 break;
1594
1595 case NDISC_ROUTER_SOLICITATION:
1596 ndisc_recv_rs(skb);
1597 break;
1598
1599 case NDISC_ROUTER_ADVERTISEMENT:
1600 ndisc_router_discovery(skb);
1601 break;
1602
1603 case NDISC_REDIRECT:
1604 ndisc_redirect_rcv(skb);
1605 break;
1606 }
1607
1608 return 0;
1609 }
1610
1611 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1612 {
1613 struct net_device *dev = ptr;
1614
1615 if (dev->nd_net != &init_net)
1616 return NOTIFY_DONE;
1617
1618 switch (event) {
1619 case NETDEV_CHANGEADDR:
1620 neigh_changeaddr(&nd_tbl, dev);
1621 fib6_run_gc(~0UL);
1622 break;
1623 case NETDEV_DOWN:
1624 neigh_ifdown(&nd_tbl, dev);
1625 fib6_run_gc(~0UL);
1626 break;
1627 default:
1628 break;
1629 }
1630
1631 return NOTIFY_DONE;
1632 }
1633
1634 static struct notifier_block ndisc_netdev_notifier = {
1635 .notifier_call = ndisc_netdev_event,
1636 };
1637
1638 #ifdef CONFIG_SYSCTL
1639 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1640 const char *func, const char *dev_name)
1641 {
1642 static char warncomm[TASK_COMM_LEN];
1643 static int warned;
1644 if (strcmp(warncomm, current->comm) && warned < 5) {
1645 strcpy(warncomm, current->comm);
1646 printk(KERN_WARNING
1647 "process `%s' is using deprecated sysctl (%s) "
1648 "net.ipv6.neigh.%s.%s; "
1649 "Use net.ipv6.neigh.%s.%s_ms "
1650 "instead.\n",
1651 warncomm, func,
1652 dev_name, ctl->procname,
1653 dev_name, ctl->procname);
1654 warned++;
1655 }
1656 }
1657
1658 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, struct file * filp, void __user *buffer, size_t *lenp, loff_t *ppos)
1659 {
1660 struct net_device *dev = ctl->extra1;
1661 struct inet6_dev *idev;
1662 int ret;
1663
1664 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1665 (strcmp(ctl->procname, "base_reachable_time") == 0))
1666 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1667
1668 if (strcmp(ctl->procname, "retrans_time") == 0)
1669 ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1670
1671 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1672 ret = proc_dointvec_jiffies(ctl, write,
1673 filp, buffer, lenp, ppos);
1674
1675 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1676 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1677 ret = proc_dointvec_ms_jiffies(ctl, write,
1678 filp, buffer, lenp, ppos);
1679 else
1680 ret = -1;
1681
1682 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1683 if (ctl->data == &idev->nd_parms->base_reachable_time)
1684 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1685 idev->tstamp = jiffies;
1686 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1687 in6_dev_put(idev);
1688 }
1689 return ret;
1690 }
1691
1692 static int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl, int __user *name,
1693 int nlen, void __user *oldval,
1694 size_t __user *oldlenp,
1695 void __user *newval, size_t newlen)
1696 {
1697 struct net_device *dev = ctl->extra1;
1698 struct inet6_dev *idev;
1699 int ret;
1700
1701 if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
1702 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
1703 ndisc_warn_deprecated_sysctl(ctl, "procfs", dev ? dev->name : "default");
1704
1705 switch (ctl->ctl_name) {
1706 case NET_NEIGH_REACHABLE_TIME:
1707 ret = sysctl_jiffies(ctl, name, nlen,
1708 oldval, oldlenp, newval, newlen);
1709 break;
1710 case NET_NEIGH_RETRANS_TIME_MS:
1711 case NET_NEIGH_REACHABLE_TIME_MS:
1712 ret = sysctl_ms_jiffies(ctl, name, nlen,
1713 oldval, oldlenp, newval, newlen);
1714 break;
1715 default:
1716 ret = 0;
1717 }
1718
1719 if (newval && newlen && ret > 0 &&
1720 dev && (idev = in6_dev_get(dev)) != NULL) {
1721 if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
1722 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
1723 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1724 idev->tstamp = jiffies;
1725 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1726 in6_dev_put(idev);
1727 }
1728
1729 return ret;
1730 }
1731
1732 #endif
1733
1734 int __init ndisc_init(struct net_proto_family *ops)
1735 {
1736 struct ipv6_pinfo *np;
1737 struct sock *sk;
1738 int err;
1739
1740 err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6, &ndisc_socket);
1741 if (err < 0) {
1742 ND_PRINTK0(KERN_ERR
1743 "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n",
1744 err);
1745 ndisc_socket = NULL; /* For safety. */
1746 return err;
1747 }
1748
1749 sk = ndisc_socket->sk;
1750 np = inet6_sk(sk);
1751 sk->sk_allocation = GFP_ATOMIC;
1752 np->hop_limit = 255;
1753 /* Do not loopback ndisc messages */
1754 np->mc_loop = 0;
1755 sk->sk_prot->unhash(sk);
1756
1757 /*
1758 * Initialize the neighbour table
1759 */
1760
1761 neigh_table_init(&nd_tbl);
1762
1763 #ifdef CONFIG_SYSCTL
1764 neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH,
1765 "ipv6",
1766 &ndisc_ifinfo_sysctl_change,
1767 &ndisc_ifinfo_sysctl_strategy);
1768 #endif
1769
1770 register_netdevice_notifier(&ndisc_netdev_notifier);
1771 return 0;
1772 }
1773
1774 void ndisc_cleanup(void)
1775 {
1776 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1777 #ifdef CONFIG_SYSCTL
1778 neigh_sysctl_unregister(&nd_tbl.parms);
1779 #endif
1780 neigh_table_clear(&nd_tbl);
1781 sock_release(ndisc_socket);
1782 ndisc_socket = NULL; /* For safety. */
1783 }
Support for the Chinese Samsung S3C2440 based development boards