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[IPV6]: Make ndisc_flow_init() common for later use.
[GitHub/moto-9609/android_kernel_motorola_exynos9610.git] / net / ipv6 / ndisc.c
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 static void __ndisc_send(struct net_device *dev,
445 struct neighbour *neigh,
446 struct in6_addr *daddr, struct in6_addr *saddr,
447 struct icmp6hdr *icmp6h, struct in6_addr *target,
448 int llinfo)
449 {
450 struct flowi fl;
451 struct dst_entry *dst;
452 struct sock *sk = ndisc_socket->sk;
453 struct sk_buff *skb;
454 struct icmp6hdr *hdr;
455 struct inet6_dev *idev;
456 int len;
457 int err;
458 u8 *opt, type;
459
460 type = icmp6h->icmp6_type;
461
462 icmpv6_flow_init(ndisc_socket->sk, &fl, type,
463 saddr, daddr, dev->ifindex);
464
465 dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output);
466 if (!dst)
467 return;
468
469 err = xfrm_lookup(&dst, &fl, NULL, 0);
470 if (err < 0)
471 return;
472
473 if (!dev->addr_len)
474 llinfo = 0;
475
476 len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0);
477 if (llinfo)
478 len += ndisc_opt_addr_space(dev);
479
480 skb = sock_alloc_send_skb(sk,
481 (MAX_HEADER + sizeof(struct ipv6hdr) +
482 len + LL_RESERVED_SPACE(dev)),
483 1, &err);
484 if (!skb) {
485 ND_PRINTK0(KERN_ERR
486 "ICMPv6 ND: %s() failed to allocate an skb.\n",
487 __FUNCTION__);
488 dst_release(dst);
489 return;
490 }
491
492 skb_reserve(skb, LL_RESERVED_SPACE(dev));
493 ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
494
495 skb->transport_header = skb->tail;
496 skb_put(skb, len);
497
498 hdr = (struct icmp6hdr *)skb_transport_header(skb);
499 memcpy(hdr, icmp6h, sizeof(*hdr));
500
501 opt = skb_transport_header(skb) + sizeof(struct icmp6hdr);
502 if (target) {
503 ipv6_addr_copy((struct in6_addr *)opt, target);
504 opt += sizeof(*target);
505 }
506
507 if (llinfo)
508 ndisc_fill_addr_option(opt, llinfo, dev->dev_addr,
509 dev->addr_len, dev->type);
510
511 hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len,
512 IPPROTO_ICMPV6,
513 csum_partial((__u8 *) hdr,
514 len, 0));
515
516 skb->dst = dst;
517
518 idev = in6_dev_get(dst->dev);
519 IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
520
521 err = NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
522 dst_output);
523 if (!err) {
524 ICMP6MSGOUT_INC_STATS(idev, type);
525 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
526 }
527
528 if (likely(idev != NULL))
529 in6_dev_put(idev);
530 }
531
532 static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
533 struct in6_addr *daddr, struct in6_addr *solicited_addr,
534 int router, int solicited, int override, int inc_opt)
535 {
536 struct in6_addr tmpaddr;
537 struct inet6_ifaddr *ifp;
538 struct in6_addr *src_addr;
539 struct icmp6hdr icmp6h = {
540 .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
541 };
542
543 /* for anycast or proxy, solicited_addr != src_addr */
544 ifp = ipv6_get_ifaddr(&init_net, solicited_addr, dev, 1);
545 if (ifp) {
546 src_addr = solicited_addr;
547 if (ifp->flags & IFA_F_OPTIMISTIC)
548 override = 0;
549 in6_ifa_put(ifp);
550 } else {
551 if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
552 return;
553 src_addr = &tmpaddr;
554 }
555
556 icmp6h.icmp6_router = router;
557 icmp6h.icmp6_solicited = solicited;
558 icmp6h.icmp6_override = override;
559
560 __ndisc_send(dev, neigh, daddr, src_addr,
561 &icmp6h, solicited_addr,
562 inc_opt ? ND_OPT_TARGET_LL_ADDR : 0);
563 }
564
565 void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
566 struct in6_addr *solicit,
567 struct in6_addr *daddr, struct in6_addr *saddr)
568 {
569 struct in6_addr addr_buf;
570 struct icmp6hdr icmp6h = {
571 .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
572 };
573
574 if (saddr == NULL) {
575 if (ipv6_get_lladdr(dev, &addr_buf,
576 (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
577 return;
578 saddr = &addr_buf;
579 }
580
581 __ndisc_send(dev, neigh, daddr, saddr,
582 &icmp6h, solicit,
583 !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0);
584 }
585
586 void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
587 struct in6_addr *daddr)
588 {
589 struct icmp6hdr icmp6h = {
590 .icmp6_type = NDISC_ROUTER_SOLICITATION,
591 };
592 int send_sllao = dev->addr_len;
593
594 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
595 /*
596 * According to section 2.2 of RFC 4429, we must not
597 * send router solicitations with a sllao from
598 * optimistic addresses, but we may send the solicitation
599 * if we don't include the sllao. So here we check
600 * if our address is optimistic, and if so, we
601 * suppress the inclusion of the sllao.
602 */
603 if (send_sllao) {
604 struct inet6_ifaddr *ifp = ipv6_get_ifaddr(&init_net, saddr,
605 dev, 1);
606 if (ifp) {
607 if (ifp->flags & IFA_F_OPTIMISTIC) {
608 send_sllao = 0;
609 }
610 in6_ifa_put(ifp);
611 } else {
612 send_sllao = 0;
613 }
614 }
615 #endif
616 __ndisc_send(dev, NULL, daddr, saddr,
617 &icmp6h, NULL,
618 send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0);
619 }
620
621
622 static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
623 {
624 /*
625 * "The sender MUST return an ICMP
626 * destination unreachable"
627 */
628 dst_link_failure(skb);
629 kfree_skb(skb);
630 }
631
632 /* Called with locked neigh: either read or both */
633
634 static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
635 {
636 struct in6_addr *saddr = NULL;
637 struct in6_addr mcaddr;
638 struct net_device *dev = neigh->dev;
639 struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
640 int probes = atomic_read(&neigh->probes);
641
642 if (skb && ipv6_chk_addr(&init_net, &ipv6_hdr(skb)->saddr, dev, 1))
643 saddr = &ipv6_hdr(skb)->saddr;
644
645 if ((probes -= neigh->parms->ucast_probes) < 0) {
646 if (!(neigh->nud_state & NUD_VALID)) {
647 ND_PRINTK1(KERN_DEBUG
648 "%s(): trying to ucast probe in NUD_INVALID: "
649 NIP6_FMT "\n",
650 __FUNCTION__,
651 NIP6(*target));
652 }
653 ndisc_send_ns(dev, neigh, target, target, saddr);
654 } else if ((probes -= neigh->parms->app_probes) < 0) {
655 #ifdef CONFIG_ARPD
656 neigh_app_ns(neigh);
657 #endif
658 } else {
659 addrconf_addr_solict_mult(target, &mcaddr);
660 ndisc_send_ns(dev, NULL, target, &mcaddr, saddr);
661 }
662 }
663
664 static void ndisc_recv_ns(struct sk_buff *skb)
665 {
666 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
667 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
668 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
669 u8 *lladdr = NULL;
670 u32 ndoptlen = skb->tail - (skb->transport_header +
671 offsetof(struct nd_msg, opt));
672 struct ndisc_options ndopts;
673 struct net_device *dev = skb->dev;
674 struct inet6_ifaddr *ifp;
675 struct inet6_dev *idev = NULL;
676 struct neighbour *neigh;
677 struct pneigh_entry *pneigh = NULL;
678 int dad = ipv6_addr_any(saddr);
679 int inc;
680 int is_router;
681
682 if (ipv6_addr_is_multicast(&msg->target)) {
683 ND_PRINTK2(KERN_WARNING
684 "ICMPv6 NS: multicast target address");
685 return;
686 }
687
688 /*
689 * RFC2461 7.1.1:
690 * DAD has to be destined for solicited node multicast address.
691 */
692 if (dad &&
693 !(daddr->s6_addr32[0] == htonl(0xff020000) &&
694 daddr->s6_addr32[1] == htonl(0x00000000) &&
695 daddr->s6_addr32[2] == htonl(0x00000001) &&
696 daddr->s6_addr [12] == 0xff )) {
697 ND_PRINTK2(KERN_WARNING
698 "ICMPv6 NS: bad DAD packet (wrong destination)\n");
699 return;
700 }
701
702 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
703 ND_PRINTK2(KERN_WARNING
704 "ICMPv6 NS: invalid ND options\n");
705 return;
706 }
707
708 if (ndopts.nd_opts_src_lladdr) {
709 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
710 if (!lladdr) {
711 ND_PRINTK2(KERN_WARNING
712 "ICMPv6 NS: invalid link-layer address length\n");
713 return;
714 }
715
716 /* RFC2461 7.1.1:
717 * If the IP source address is the unspecified address,
718 * there MUST NOT be source link-layer address option
719 * in the message.
720 */
721 if (dad) {
722 ND_PRINTK2(KERN_WARNING
723 "ICMPv6 NS: bad DAD packet (link-layer address option)\n");
724 return;
725 }
726 }
727
728 inc = ipv6_addr_is_multicast(daddr);
729
730 if ((ifp = ipv6_get_ifaddr(&init_net, &msg->target, dev, 1)) != NULL) {
731
732 if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
733 if (dad) {
734 if (dev->type == ARPHRD_IEEE802_TR) {
735 const unsigned char *sadr;
736 sadr = skb_mac_header(skb);
737 if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
738 sadr[9] == dev->dev_addr[1] &&
739 sadr[10] == dev->dev_addr[2] &&
740 sadr[11] == dev->dev_addr[3] &&
741 sadr[12] == dev->dev_addr[4] &&
742 sadr[13] == dev->dev_addr[5]) {
743 /* looped-back to us */
744 goto out;
745 }
746 }
747
748 /*
749 * We are colliding with another node
750 * who is doing DAD
751 * so fail our DAD process
752 */
753 addrconf_dad_failure(ifp);
754 return;
755 } else {
756 /*
757 * This is not a dad solicitation.
758 * If we are an optimistic node,
759 * we should respond.
760 * Otherwise, we should ignore it.
761 */
762 if (!(ifp->flags & IFA_F_OPTIMISTIC))
763 goto out;
764 }
765 }
766
767 idev = ifp->idev;
768 } else {
769 idev = in6_dev_get(dev);
770 if (!idev) {
771 /* XXX: count this drop? */
772 return;
773 }
774
775 if (ipv6_chk_acast_addr(dev, &msg->target) ||
776 (idev->cnf.forwarding &&
777 (ipv6_devconf.proxy_ndp || idev->cnf.proxy_ndp) &&
778 (pneigh = pneigh_lookup(&nd_tbl, &init_net,
779 &msg->target, dev, 0)) != NULL)) {
780 if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
781 skb->pkt_type != PACKET_HOST &&
782 inc != 0 &&
783 idev->nd_parms->proxy_delay != 0) {
784 /*
785 * for anycast or proxy,
786 * sender should delay its response
787 * by a random time between 0 and
788 * MAX_ANYCAST_DELAY_TIME seconds.
789 * (RFC2461) -- yoshfuji
790 */
791 struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
792 if (n)
793 pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
794 goto out;
795 }
796 } else
797 goto out;
798 }
799
800 is_router = !!(pneigh ? pneigh->flags & NTF_ROUTER : idev->cnf.forwarding);
801
802 if (dad) {
803 struct in6_addr maddr;
804
805 ipv6_addr_all_nodes(&maddr);
806 ndisc_send_na(dev, NULL, &maddr, &msg->target,
807 is_router, 0, (ifp != NULL), 1);
808 goto out;
809 }
810
811 if (inc)
812 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
813 else
814 NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
815
816 /*
817 * update / create cache entry
818 * for the source address
819 */
820 neigh = __neigh_lookup(&nd_tbl, saddr, dev,
821 !inc || lladdr || !dev->addr_len);
822 if (neigh)
823 neigh_update(neigh, lladdr, NUD_STALE,
824 NEIGH_UPDATE_F_WEAK_OVERRIDE|
825 NEIGH_UPDATE_F_OVERRIDE);
826 if (neigh || !dev->header_ops) {
827 ndisc_send_na(dev, neigh, saddr, &msg->target,
828 is_router,
829 1, (ifp != NULL && inc), inc);
830 if (neigh)
831 neigh_release(neigh);
832 }
833
834 out:
835 if (ifp)
836 in6_ifa_put(ifp);
837 else
838 in6_dev_put(idev);
839
840 return;
841 }
842
843 static void ndisc_recv_na(struct sk_buff *skb)
844 {
845 struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
846 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
847 struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
848 u8 *lladdr = NULL;
849 u32 ndoptlen = skb->tail - (skb->transport_header +
850 offsetof(struct nd_msg, opt));
851 struct ndisc_options ndopts;
852 struct net_device *dev = skb->dev;
853 struct inet6_ifaddr *ifp;
854 struct neighbour *neigh;
855
856 if (skb->len < sizeof(struct nd_msg)) {
857 ND_PRINTK2(KERN_WARNING
858 "ICMPv6 NA: packet too short\n");
859 return;
860 }
861
862 if (ipv6_addr_is_multicast(&msg->target)) {
863 ND_PRINTK2(KERN_WARNING
864 "ICMPv6 NA: target address is multicast.\n");
865 return;
866 }
867
868 if (ipv6_addr_is_multicast(daddr) &&
869 msg->icmph.icmp6_solicited) {
870 ND_PRINTK2(KERN_WARNING
871 "ICMPv6 NA: solicited NA is multicasted.\n");
872 return;
873 }
874
875 if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
876 ND_PRINTK2(KERN_WARNING
877 "ICMPv6 NS: invalid ND option\n");
878 return;
879 }
880 if (ndopts.nd_opts_tgt_lladdr) {
881 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
882 if (!lladdr) {
883 ND_PRINTK2(KERN_WARNING
884 "ICMPv6 NA: invalid link-layer address length\n");
885 return;
886 }
887 }
888 if ((ifp = ipv6_get_ifaddr(&init_net, &msg->target, dev, 1))) {
889 if (ifp->flags & IFA_F_TENTATIVE) {
890 addrconf_dad_failure(ifp);
891 return;
892 }
893 /* What should we make now? The advertisement
894 is invalid, but ndisc specs say nothing
895 about it. It could be misconfiguration, or
896 an smart proxy agent tries to help us :-)
897 */
898 ND_PRINTK1(KERN_WARNING
899 "ICMPv6 NA: someone advertises our address on %s!\n",
900 ifp->idev->dev->name);
901 in6_ifa_put(ifp);
902 return;
903 }
904 neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
905
906 if (neigh) {
907 u8 old_flags = neigh->flags;
908
909 if (neigh->nud_state & NUD_FAILED)
910 goto out;
911
912 /*
913 * Don't update the neighbor cache entry on a proxy NA from
914 * ourselves because either the proxied node is off link or it
915 * has already sent a NA to us.
916 */
917 if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
918 ipv6_devconf.forwarding && ipv6_devconf.proxy_ndp &&
919 pneigh_lookup(&nd_tbl, &init_net, &msg->target, dev, 0)) {
920 /* XXX: idev->cnf.prixy_ndp */
921 goto out;
922 }
923
924 neigh_update(neigh, lladdr,
925 msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
926 NEIGH_UPDATE_F_WEAK_OVERRIDE|
927 (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
928 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
929 (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
930
931 if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
932 /*
933 * Change: router to host
934 */
935 struct rt6_info *rt;
936 rt = rt6_get_dflt_router(saddr, dev);
937 if (rt)
938 ip6_del_rt(rt);
939 }
940
941 out:
942 neigh_release(neigh);
943 }
944 }
945
946 static void ndisc_recv_rs(struct sk_buff *skb)
947 {
948 struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
949 unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
950 struct neighbour *neigh;
951 struct inet6_dev *idev;
952 struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
953 struct ndisc_options ndopts;
954 u8 *lladdr = NULL;
955
956 if (skb->len < sizeof(*rs_msg))
957 return;
958
959 idev = in6_dev_get(skb->dev);
960 if (!idev) {
961 if (net_ratelimit())
962 ND_PRINTK1("ICMP6 RS: can't find in6 device\n");
963 return;
964 }
965
966 /* Don't accept RS if we're not in router mode */
967 if (!idev->cnf.forwarding)
968 goto out;
969
970 /*
971 * Don't update NCE if src = ::;
972 * this implies that the source node has no ip address assigned yet.
973 */
974 if (ipv6_addr_any(saddr))
975 goto out;
976
977 /* Parse ND options */
978 if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
979 if (net_ratelimit())
980 ND_PRINTK2("ICMP6 NS: invalid ND option, ignored\n");
981 goto out;
982 }
983
984 if (ndopts.nd_opts_src_lladdr) {
985 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
986 skb->dev);
987 if (!lladdr)
988 goto out;
989 }
990
991 neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
992 if (neigh) {
993 neigh_update(neigh, lladdr, NUD_STALE,
994 NEIGH_UPDATE_F_WEAK_OVERRIDE|
995 NEIGH_UPDATE_F_OVERRIDE|
996 NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
997 neigh_release(neigh);
998 }
999 out:
1000 in6_dev_put(idev);
1001 }
1002
1003 static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
1004 {
1005 struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
1006 struct sk_buff *skb;
1007 struct nlmsghdr *nlh;
1008 struct nduseroptmsg *ndmsg;
1009 int err;
1010 int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
1011 + (opt->nd_opt_len << 3));
1012 size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
1013
1014 skb = nlmsg_new(msg_size, GFP_ATOMIC);
1015 if (skb == NULL) {
1016 err = -ENOBUFS;
1017 goto errout;
1018 }
1019
1020 nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
1021 if (nlh == NULL) {
1022 goto nla_put_failure;
1023 }
1024
1025 ndmsg = nlmsg_data(nlh);
1026 ndmsg->nduseropt_family = AF_INET6;
1027 ndmsg->nduseropt_ifindex = ra->dev->ifindex;
1028 ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
1029 ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
1030 ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
1031
1032 memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
1033
1034 NLA_PUT(skb, NDUSEROPT_SRCADDR, sizeof(struct in6_addr),
1035 &ipv6_hdr(ra)->saddr);
1036 nlmsg_end(skb, nlh);
1037
1038 err = rtnl_notify(skb, &init_net, 0, RTNLGRP_ND_USEROPT, NULL,
1039 GFP_ATOMIC);
1040 if (err < 0)
1041 goto errout;
1042
1043 return;
1044
1045 nla_put_failure:
1046 nlmsg_free(skb);
1047 err = -EMSGSIZE;
1048 errout:
1049 rtnl_set_sk_err(&init_net, RTNLGRP_ND_USEROPT, err);
1050 }
1051
1052 static void ndisc_router_discovery(struct sk_buff *skb)
1053 {
1054 struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
1055 struct neighbour *neigh = NULL;
1056 struct inet6_dev *in6_dev;
1057 struct rt6_info *rt = NULL;
1058 int lifetime;
1059 struct ndisc_options ndopts;
1060 int optlen;
1061 unsigned int pref = 0;
1062
1063 __u8 * opt = (__u8 *)(ra_msg + 1);
1064
1065 optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
1066
1067 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1068 ND_PRINTK2(KERN_WARNING
1069 "ICMPv6 RA: source address is not link-local.\n");
1070 return;
1071 }
1072 if (optlen < 0) {
1073 ND_PRINTK2(KERN_WARNING
1074 "ICMPv6 RA: packet too short\n");
1075 return;
1076 }
1077
1078 /*
1079 * set the RA_RECV flag in the interface
1080 */
1081
1082 in6_dev = in6_dev_get(skb->dev);
1083 if (in6_dev == NULL) {
1084 ND_PRINTK0(KERN_ERR
1085 "ICMPv6 RA: can't find inet6 device for %s.\n",
1086 skb->dev->name);
1087 return;
1088 }
1089 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra) {
1090 in6_dev_put(in6_dev);
1091 return;
1092 }
1093
1094 if (!ndisc_parse_options(opt, optlen, &ndopts)) {
1095 in6_dev_put(in6_dev);
1096 ND_PRINTK2(KERN_WARNING
1097 "ICMP6 RA: invalid ND options\n");
1098 return;
1099 }
1100
1101 if (in6_dev->if_flags & IF_RS_SENT) {
1102 /*
1103 * flag that an RA was received after an RS was sent
1104 * out on this interface.
1105 */
1106 in6_dev->if_flags |= IF_RA_RCVD;
1107 }
1108
1109 /*
1110 * Remember the managed/otherconf flags from most recently
1111 * received RA message (RFC 2462) -- yoshfuji
1112 */
1113 in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
1114 IF_RA_OTHERCONF)) |
1115 (ra_msg->icmph.icmp6_addrconf_managed ?
1116 IF_RA_MANAGED : 0) |
1117 (ra_msg->icmph.icmp6_addrconf_other ?
1118 IF_RA_OTHERCONF : 0);
1119
1120 if (!in6_dev->cnf.accept_ra_defrtr)
1121 goto skip_defrtr;
1122
1123 lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
1124
1125 #ifdef CONFIG_IPV6_ROUTER_PREF
1126 pref = ra_msg->icmph.icmp6_router_pref;
1127 /* 10b is handled as if it were 00b (medium) */
1128 if (pref == ICMPV6_ROUTER_PREF_INVALID ||
1129 !in6_dev->cnf.accept_ra_rtr_pref)
1130 pref = ICMPV6_ROUTER_PREF_MEDIUM;
1131 #endif
1132
1133 rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
1134
1135 if (rt)
1136 neigh = rt->rt6i_nexthop;
1137
1138 if (rt && lifetime == 0) {
1139 neigh_clone(neigh);
1140 ip6_del_rt(rt);
1141 rt = NULL;
1142 }
1143
1144 if (rt == NULL && lifetime) {
1145 ND_PRINTK3(KERN_DEBUG
1146 "ICMPv6 RA: adding default router.\n");
1147
1148 rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
1149 if (rt == NULL) {
1150 ND_PRINTK0(KERN_ERR
1151 "ICMPv6 RA: %s() failed to add default route.\n",
1152 __FUNCTION__);
1153 in6_dev_put(in6_dev);
1154 return;
1155 }
1156
1157 neigh = rt->rt6i_nexthop;
1158 if (neigh == NULL) {
1159 ND_PRINTK0(KERN_ERR
1160 "ICMPv6 RA: %s() got default router without neighbour.\n",
1161 __FUNCTION__);
1162 dst_release(&rt->u.dst);
1163 in6_dev_put(in6_dev);
1164 return;
1165 }
1166 neigh->flags |= NTF_ROUTER;
1167 } else if (rt) {
1168 rt->rt6i_flags |= (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
1169 }
1170
1171 if (rt)
1172 rt->rt6i_expires = jiffies + (HZ * lifetime);
1173
1174 if (ra_msg->icmph.icmp6_hop_limit) {
1175 in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
1176 if (rt)
1177 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit;
1178 }
1179
1180 skip_defrtr:
1181
1182 /*
1183 * Update Reachable Time and Retrans Timer
1184 */
1185
1186 if (in6_dev->nd_parms) {
1187 unsigned long rtime = ntohl(ra_msg->retrans_timer);
1188
1189 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
1190 rtime = (rtime*HZ)/1000;
1191 if (rtime < HZ/10)
1192 rtime = HZ/10;
1193 in6_dev->nd_parms->retrans_time = rtime;
1194 in6_dev->tstamp = jiffies;
1195 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1196 }
1197
1198 rtime = ntohl(ra_msg->reachable_time);
1199 if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
1200 rtime = (rtime*HZ)/1000;
1201
1202 if (rtime < HZ/10)
1203 rtime = HZ/10;
1204
1205 if (rtime != in6_dev->nd_parms->base_reachable_time) {
1206 in6_dev->nd_parms->base_reachable_time = rtime;
1207 in6_dev->nd_parms->gc_staletime = 3 * rtime;
1208 in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
1209 in6_dev->tstamp = jiffies;
1210 inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
1211 }
1212 }
1213 }
1214
1215 /*
1216 * Process options.
1217 */
1218
1219 if (!neigh)
1220 neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
1221 skb->dev, 1);
1222 if (neigh) {
1223 u8 *lladdr = NULL;
1224 if (ndopts.nd_opts_src_lladdr) {
1225 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
1226 skb->dev);
1227 if (!lladdr) {
1228 ND_PRINTK2(KERN_WARNING
1229 "ICMPv6 RA: invalid link-layer address length\n");
1230 goto out;
1231 }
1232 }
1233 neigh_update(neigh, lladdr, NUD_STALE,
1234 NEIGH_UPDATE_F_WEAK_OVERRIDE|
1235 NEIGH_UPDATE_F_OVERRIDE|
1236 NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
1237 NEIGH_UPDATE_F_ISROUTER);
1238 }
1239
1240 #ifdef CONFIG_IPV6_ROUTE_INFO
1241 if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
1242 struct nd_opt_hdr *p;
1243 for (p = ndopts.nd_opts_ri;
1244 p;
1245 p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
1246 if (((struct route_info *)p)->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
1247 continue;
1248 rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
1249 &ipv6_hdr(skb)->saddr);
1250 }
1251 }
1252 #endif
1253
1254 if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
1255 struct nd_opt_hdr *p;
1256 for (p = ndopts.nd_opts_pi;
1257 p;
1258 p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
1259 addrconf_prefix_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3);
1260 }
1261 }
1262
1263 if (ndopts.nd_opts_mtu) {
1264 __be32 n;
1265 u32 mtu;
1266
1267 memcpy(&n, ((u8*)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
1268 mtu = ntohl(n);
1269
1270 if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
1271 ND_PRINTK2(KERN_WARNING
1272 "ICMPv6 RA: invalid mtu: %d\n",
1273 mtu);
1274 } else if (in6_dev->cnf.mtu6 != mtu) {
1275 in6_dev->cnf.mtu6 = mtu;
1276
1277 if (rt)
1278 rt->u.dst.metrics[RTAX_MTU-1] = mtu;
1279
1280 rt6_mtu_change(skb->dev, mtu);
1281 }
1282 }
1283
1284 if (ndopts.nd_useropts) {
1285 struct nd_opt_hdr *p;
1286 for (p = ndopts.nd_useropts;
1287 p;
1288 p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
1289 ndisc_ra_useropt(skb, p);
1290 }
1291 }
1292
1293 if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
1294 ND_PRINTK2(KERN_WARNING
1295 "ICMPv6 RA: invalid RA options");
1296 }
1297 out:
1298 if (rt)
1299 dst_release(&rt->u.dst);
1300 else if (neigh)
1301 neigh_release(neigh);
1302 in6_dev_put(in6_dev);
1303 }
1304
1305 static void ndisc_redirect_rcv(struct sk_buff *skb)
1306 {
1307 struct inet6_dev *in6_dev;
1308 struct icmp6hdr *icmph;
1309 struct in6_addr *dest;
1310 struct in6_addr *target; /* new first hop to destination */
1311 struct neighbour *neigh;
1312 int on_link = 0;
1313 struct ndisc_options ndopts;
1314 int optlen;
1315 u8 *lladdr = NULL;
1316
1317 if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
1318 ND_PRINTK2(KERN_WARNING
1319 "ICMPv6 Redirect: source address is not link-local.\n");
1320 return;
1321 }
1322
1323 optlen = skb->tail - skb->transport_header;
1324 optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1325
1326 if (optlen < 0) {
1327 ND_PRINTK2(KERN_WARNING
1328 "ICMPv6 Redirect: packet too short\n");
1329 return;
1330 }
1331
1332 icmph = icmp6_hdr(skb);
1333 target = (struct in6_addr *) (icmph + 1);
1334 dest = target + 1;
1335
1336 if (ipv6_addr_is_multicast(dest)) {
1337 ND_PRINTK2(KERN_WARNING
1338 "ICMPv6 Redirect: destination address is multicast.\n");
1339 return;
1340 }
1341
1342 if (ipv6_addr_equal(dest, target)) {
1343 on_link = 1;
1344 } else if (ipv6_addr_type(target) !=
1345 (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1346 ND_PRINTK2(KERN_WARNING
1347 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1348 return;
1349 }
1350
1351 in6_dev = in6_dev_get(skb->dev);
1352 if (!in6_dev)
1353 return;
1354 if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) {
1355 in6_dev_put(in6_dev);
1356 return;
1357 }
1358
1359 /* RFC2461 8.1:
1360 * The IP source address of the Redirect MUST be the same as the current
1361 * first-hop router for the specified ICMP Destination Address.
1362 */
1363
1364 if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) {
1365 ND_PRINTK2(KERN_WARNING
1366 "ICMPv6 Redirect: invalid ND options\n");
1367 in6_dev_put(in6_dev);
1368 return;
1369 }
1370 if (ndopts.nd_opts_tgt_lladdr) {
1371 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
1372 skb->dev);
1373 if (!lladdr) {
1374 ND_PRINTK2(KERN_WARNING
1375 "ICMPv6 Redirect: invalid link-layer address length\n");
1376 in6_dev_put(in6_dev);
1377 return;
1378 }
1379 }
1380
1381 neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
1382 if (neigh) {
1383 rt6_redirect(dest, &ipv6_hdr(skb)->daddr,
1384 &ipv6_hdr(skb)->saddr, neigh, lladdr,
1385 on_link);
1386 neigh_release(neigh);
1387 }
1388 in6_dev_put(in6_dev);
1389 }
1390
1391 void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
1392 struct in6_addr *target)
1393 {
1394 struct sock *sk = ndisc_socket->sk;
1395 int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
1396 struct sk_buff *buff;
1397 struct icmp6hdr *icmph;
1398 struct in6_addr saddr_buf;
1399 struct in6_addr *addrp;
1400 struct net_device *dev;
1401 struct rt6_info *rt;
1402 struct dst_entry *dst;
1403 struct inet6_dev *idev;
1404 struct flowi fl;
1405 u8 *opt;
1406 int rd_len;
1407 int err;
1408 int hlen;
1409 u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
1410
1411 dev = skb->dev;
1412
1413 if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
1414 ND_PRINTK2(KERN_WARNING
1415 "ICMPv6 Redirect: no link-local address on %s\n",
1416 dev->name);
1417 return;
1418 }
1419
1420 if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
1421 ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
1422 ND_PRINTK2(KERN_WARNING
1423 "ICMPv6 Redirect: target address is not link-local unicast.\n");
1424 return;
1425 }
1426
1427 icmpv6_flow_init(ndisc_socket->sk, &fl, NDISC_REDIRECT,
1428 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
1429
1430 dst = ip6_route_output(NULL, &fl);
1431 if (dst == NULL)
1432 return;
1433
1434 err = xfrm_lookup(&dst, &fl, NULL, 0);
1435 if (err)
1436 return;
1437
1438 rt = (struct rt6_info *) dst;
1439
1440 if (rt->rt6i_flags & RTF_GATEWAY) {
1441 ND_PRINTK2(KERN_WARNING
1442 "ICMPv6 Redirect: destination is not a neighbour.\n");
1443 dst_release(dst);
1444 return;
1445 }
1446 if (!xrlim_allow(dst, 1*HZ)) {
1447 dst_release(dst);
1448 return;
1449 }
1450
1451 if (dev->addr_len) {
1452 read_lock_bh(&neigh->lock);
1453 if (neigh->nud_state & NUD_VALID) {
1454 memcpy(ha_buf, neigh->ha, dev->addr_len);
1455 read_unlock_bh(&neigh->lock);
1456 ha = ha_buf;
1457 len += ndisc_opt_addr_space(dev);
1458 } else
1459 read_unlock_bh(&neigh->lock);
1460 }
1461
1462 rd_len = min_t(unsigned int,
1463 IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8);
1464 rd_len &= ~0x7;
1465 len += rd_len;
1466
1467 buff = sock_alloc_send_skb(sk,
1468 (MAX_HEADER + sizeof(struct ipv6hdr) +
1469 len + LL_RESERVED_SPACE(dev)),
1470 1, &err);
1471 if (buff == NULL) {
1472 ND_PRINTK0(KERN_ERR
1473 "ICMPv6 Redirect: %s() failed to allocate an skb.\n",
1474 __FUNCTION__);
1475 dst_release(dst);
1476 return;
1477 }
1478
1479 hlen = 0;
1480
1481 skb_reserve(buff, LL_RESERVED_SPACE(dev));
1482 ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
1483 IPPROTO_ICMPV6, len);
1484
1485 skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
1486 skb_put(buff, len);
1487 icmph = icmp6_hdr(buff);
1488
1489 memset(icmph, 0, sizeof(struct icmp6hdr));
1490 icmph->icmp6_type = NDISC_REDIRECT;
1491
1492 /*
1493 * copy target and destination addresses
1494 */
1495
1496 addrp = (struct in6_addr *)(icmph + 1);
1497 ipv6_addr_copy(addrp, target);
1498 addrp++;
1499 ipv6_addr_copy(addrp, &ipv6_hdr(skb)->daddr);
1500
1501 opt = (u8*) (addrp + 1);
1502
1503 /*
1504 * include target_address option
1505 */
1506
1507 if (ha)
1508 opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha,
1509 dev->addr_len, dev->type);
1510
1511 /*
1512 * build redirect option and copy skb over to the new packet.
1513 */
1514
1515 memset(opt, 0, 8);
1516 *(opt++) = ND_OPT_REDIRECT_HDR;
1517 *(opt++) = (rd_len >> 3);
1518 opt += 6;
1519
1520 memcpy(opt, ipv6_hdr(skb), rd_len - 8);
1521
1522 icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr,
1523 len, IPPROTO_ICMPV6,
1524 csum_partial((u8 *) icmph, len, 0));
1525
1526 buff->dst = dst;
1527 idev = in6_dev_get(dst->dev);
1528 IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
1529 err = NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, buff, NULL, dst->dev,
1530 dst_output);
1531 if (!err) {
1532 ICMP6MSGOUT_INC_STATS(idev, NDISC_REDIRECT);
1533 ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS);
1534 }
1535
1536 if (likely(idev != NULL))
1537 in6_dev_put(idev);
1538 }
1539
1540 static void pndisc_redo(struct sk_buff *skb)
1541 {
1542 ndisc_recv_ns(skb);
1543 kfree_skb(skb);
1544 }
1545
1546 int ndisc_rcv(struct sk_buff *skb)
1547 {
1548 struct nd_msg *msg;
1549
1550 if (!pskb_may_pull(skb, skb->len))
1551 return 0;
1552
1553 msg = (struct nd_msg *)skb_transport_header(skb);
1554
1555 __skb_push(skb, skb->data - skb_transport_header(skb));
1556
1557 if (ipv6_hdr(skb)->hop_limit != 255) {
1558 ND_PRINTK2(KERN_WARNING
1559 "ICMPv6 NDISC: invalid hop-limit: %d\n",
1560 ipv6_hdr(skb)->hop_limit);
1561 return 0;
1562 }
1563
1564 if (msg->icmph.icmp6_code != 0) {
1565 ND_PRINTK2(KERN_WARNING
1566 "ICMPv6 NDISC: invalid ICMPv6 code: %d\n",
1567 msg->icmph.icmp6_code);
1568 return 0;
1569 }
1570
1571 memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
1572
1573 switch (msg->icmph.icmp6_type) {
1574 case NDISC_NEIGHBOUR_SOLICITATION:
1575 ndisc_recv_ns(skb);
1576 break;
1577
1578 case NDISC_NEIGHBOUR_ADVERTISEMENT:
1579 ndisc_recv_na(skb);
1580 break;
1581
1582 case NDISC_ROUTER_SOLICITATION:
1583 ndisc_recv_rs(skb);
1584 break;
1585
1586 case NDISC_ROUTER_ADVERTISEMENT:
1587 ndisc_router_discovery(skb);
1588 break;
1589
1590 case NDISC_REDIRECT:
1591 ndisc_redirect_rcv(skb);
1592 break;
1593 }
1594
1595 return 0;
1596 }
1597
1598 static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1599 {
1600 struct net_device *dev = ptr;
1601
1602 if (dev->nd_net != &init_net)
1603 return NOTIFY_DONE;
1604
1605 switch (event) {
1606 case NETDEV_CHANGEADDR:
1607 neigh_changeaddr(&nd_tbl, dev);
1608 fib6_run_gc(~0UL);
1609 break;
1610 case NETDEV_DOWN:
1611 neigh_ifdown(&nd_tbl, dev);
1612 fib6_run_gc(~0UL);
1613 break;
1614 default:
1615 break;
1616 }
1617
1618 return NOTIFY_DONE;
1619 }
1620
1621 static struct notifier_block ndisc_netdev_notifier = {
1622 .notifier_call = ndisc_netdev_event,
1623 };
1624
1625 #ifdef CONFIG_SYSCTL
1626 static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
1627 const char *func, const char *dev_name)
1628 {
1629 static char warncomm[TASK_COMM_LEN];
1630 static int warned;
1631 if (strcmp(warncomm, current->comm) && warned < 5) {
1632 strcpy(warncomm, current->comm);
1633 printk(KERN_WARNING
1634 "process `%s' is using deprecated sysctl (%s) "
1635 "net.ipv6.neigh.%s.%s; "
1636 "Use net.ipv6.neigh.%s.%s_ms "
1637 "instead.\n",
1638 warncomm, func,
1639 dev_name, ctl->procname,
1640 dev_name, ctl->procname);
1641 warned++;
1642 }
1643 }
1644
1645 int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, struct file * filp, void __user *buffer, size_t *lenp, loff_t *ppos)
1646 {
1647 struct net_device *dev = ctl->extra1;
1648 struct inet6_dev *idev;
1649 int ret;
1650
1651 if ((strcmp(ctl->procname, "retrans_time") == 0) ||
1652 (strcmp(ctl->procname, "base_reachable_time") == 0))
1653 ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
1654
1655 if (strcmp(ctl->procname, "retrans_time") == 0)
1656 ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
1657
1658 else if (strcmp(ctl->procname, "base_reachable_time") == 0)
1659 ret = proc_dointvec_jiffies(ctl, write,
1660 filp, buffer, lenp, ppos);
1661
1662 else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
1663 (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
1664 ret = proc_dointvec_ms_jiffies(ctl, write,
1665 filp, buffer, lenp, ppos);
1666 else
1667 ret = -1;
1668
1669 if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
1670 if (ctl->data == &idev->nd_parms->base_reachable_time)
1671 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1672 idev->tstamp = jiffies;
1673 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1674 in6_dev_put(idev);
1675 }
1676 return ret;
1677 }
1678
1679 static int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl, int __user *name,
1680 int nlen, void __user *oldval,
1681 size_t __user *oldlenp,
1682 void __user *newval, size_t newlen)
1683 {
1684 struct net_device *dev = ctl->extra1;
1685 struct inet6_dev *idev;
1686 int ret;
1687
1688 if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME ||
1689 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME)
1690 ndisc_warn_deprecated_sysctl(ctl, "procfs", dev ? dev->name : "default");
1691
1692 switch (ctl->ctl_name) {
1693 case NET_NEIGH_REACHABLE_TIME:
1694 ret = sysctl_jiffies(ctl, name, nlen,
1695 oldval, oldlenp, newval, newlen);
1696 break;
1697 case NET_NEIGH_RETRANS_TIME_MS:
1698 case NET_NEIGH_REACHABLE_TIME_MS:
1699 ret = sysctl_ms_jiffies(ctl, name, nlen,
1700 oldval, oldlenp, newval, newlen);
1701 break;
1702 default:
1703 ret = 0;
1704 }
1705
1706 if (newval && newlen && ret > 0 &&
1707 dev && (idev = in6_dev_get(dev)) != NULL) {
1708 if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME ||
1709 ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS)
1710 idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time);
1711 idev->tstamp = jiffies;
1712 inet6_ifinfo_notify(RTM_NEWLINK, idev);
1713 in6_dev_put(idev);
1714 }
1715
1716 return ret;
1717 }
1718
1719 #endif
1720
1721 int __init ndisc_init(void)
1722 {
1723 struct ipv6_pinfo *np;
1724 struct sock *sk;
1725 int err;
1726
1727 err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6, &ndisc_socket);
1728 if (err < 0) {
1729 ND_PRINTK0(KERN_ERR
1730 "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n",
1731 err);
1732 ndisc_socket = NULL; /* For safety. */
1733 return err;
1734 }
1735
1736 sk = ndisc_socket->sk;
1737 np = inet6_sk(sk);
1738 sk->sk_allocation = GFP_ATOMIC;
1739 np->hop_limit = 255;
1740 /* Do not loopback ndisc messages */
1741 np->mc_loop = 0;
1742 sk->sk_prot->unhash(sk);
1743
1744 /*
1745 * Initialize the neighbour table
1746 */
1747
1748 neigh_table_init(&nd_tbl);
1749
1750 #ifdef CONFIG_SYSCTL
1751 neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH,
1752 "ipv6",
1753 &ndisc_ifinfo_sysctl_change,
1754 &ndisc_ifinfo_sysctl_strategy);
1755 #endif
1756
1757 register_netdevice_notifier(&ndisc_netdev_notifier);
1758 return 0;
1759 }
1760
1761 void ndisc_cleanup(void)
1762 {
1763 unregister_netdevice_notifier(&ndisc_netdev_notifier);
1764 #ifdef CONFIG_SYSCTL
1765 neigh_sysctl_unregister(&nd_tbl.parms);
1766 #endif
1767 neigh_table_clear(&nd_tbl);
1768 sock_release(ndisc_socket);
1769 ndisc_socket = NULL; /* For safety. */
1770 }