xref: /linux/net/ipv6/ipv6_sockglue.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  *	IPv6 BSD socket options interface
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *
8  *	Based on linux/net/ipv4/ip_sockglue.c
9  *
10  *	$Id: ipv6_sockglue.c,v 1.41 2002/02/01 22:01:04 davem Exp $
11  *
12  *	This program is free software; you can redistribute it and/or
13  *      modify it under the terms of the GNU General Public License
14  *      as published by the Free Software Foundation; either version
15  *      2 of the License, or (at your option) any later version.
16  *
17  *	FIXME: Make the setsockopt code POSIX compliant: That is
18  *
19  *	o	Return -EINVAL for setsockopt of short lengths
20  *	o	Truncate getsockopt returns
21  *	o	Return an optlen of the truncated length if need be
22  *
23  *	Changes:
24  *	David L Stevens <dlstevens@us.ibm.com>:
25  *		- added multicast source filtering API for MLDv2
26  */
27 
28 #include <linux/module.h>
29 #include <linux/capability.h>
30 #include <linux/config.h>
31 #include <linux/errno.h>
32 #include <linux/types.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/sched.h>
36 #include <linux/net.h>
37 #include <linux/in6.h>
38 #include <linux/netdevice.h>
39 #include <linux/if_arp.h>
40 #include <linux/init.h>
41 #include <linux/sysctl.h>
42 #include <linux/netfilter.h>
43 
44 #include <net/sock.h>
45 #include <net/snmp.h>
46 #include <net/ipv6.h>
47 #include <net/ndisc.h>
48 #include <net/protocol.h>
49 #include <net/transp_v6.h>
50 #include <net/ip6_route.h>
51 #include <net/addrconf.h>
52 #include <net/inet_common.h>
53 #include <net/tcp.h>
54 #include <net/udp.h>
55 #include <net/xfrm.h>
56 
57 #include <asm/uaccess.h>
58 
59 DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics) __read_mostly;
60 
61 static struct packet_type ipv6_packet_type = {
62 	.type = __constant_htons(ETH_P_IPV6),
63 	.func = ipv6_rcv,
64 };
65 
66 struct ip6_ra_chain *ip6_ra_chain;
67 DEFINE_RWLOCK(ip6_ra_lock);
68 
69 int ip6_ra_control(struct sock *sk, int sel, void (*destructor)(struct sock *))
70 {
71 	struct ip6_ra_chain *ra, *new_ra, **rap;
72 
73 	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
74 	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num != IPPROTO_RAW)
75 		return -EINVAL;
76 
77 	new_ra = (sel>=0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
78 
79 	write_lock_bh(&ip6_ra_lock);
80 	for (rap = &ip6_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
81 		if (ra->sk == sk) {
82 			if (sel>=0) {
83 				write_unlock_bh(&ip6_ra_lock);
84 				kfree(new_ra);
85 				return -EADDRINUSE;
86 			}
87 
88 			*rap = ra->next;
89 			write_unlock_bh(&ip6_ra_lock);
90 
91 			if (ra->destructor)
92 				ra->destructor(sk);
93 			sock_put(sk);
94 			kfree(ra);
95 			return 0;
96 		}
97 	}
98 	if (new_ra == NULL) {
99 		write_unlock_bh(&ip6_ra_lock);
100 		return -ENOBUFS;
101 	}
102 	new_ra->sk = sk;
103 	new_ra->sel = sel;
104 	new_ra->destructor = destructor;
105 	new_ra->next = ra;
106 	*rap = new_ra;
107 	sock_hold(sk);
108 	write_unlock_bh(&ip6_ra_lock);
109 	return 0;
110 }
111 
112 static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
113 		    char __user *optval, int optlen)
114 {
115 	struct ipv6_pinfo *np = inet6_sk(sk);
116 	int val, valbool;
117 	int retv = -ENOPROTOOPT;
118 
119 	if (optval == NULL)
120 		val=0;
121 	else if (get_user(val, (int __user *) optval))
122 		return -EFAULT;
123 
124 	valbool = (val!=0);
125 
126 	lock_sock(sk);
127 
128 	switch (optname) {
129 
130 	case IPV6_ADDRFORM:
131 		if (val == PF_INET) {
132 			struct ipv6_txoptions *opt;
133 			struct sk_buff *pktopt;
134 
135 			if (sk->sk_protocol != IPPROTO_UDP &&
136 			    sk->sk_protocol != IPPROTO_TCP)
137 				break;
138 
139 			if (sk->sk_state != TCP_ESTABLISHED) {
140 				retv = -ENOTCONN;
141 				break;
142 			}
143 
144 			if (ipv6_only_sock(sk) ||
145 			    !(ipv6_addr_type(&np->daddr) & IPV6_ADDR_MAPPED)) {
146 				retv = -EADDRNOTAVAIL;
147 				break;
148 			}
149 
150 			fl6_free_socklist(sk);
151 			ipv6_sock_mc_close(sk);
152 
153 			/*
154 			 * Sock is moving from IPv6 to IPv4 (sk_prot), so
155 			 * remove it from the refcnt debug socks count in the
156 			 * original family...
157 			 */
158 			sk_refcnt_debug_dec(sk);
159 
160 			if (sk->sk_protocol == IPPROTO_TCP) {
161 				struct inet_connection_sock *icsk = inet_csk(sk);
162 
163 				local_bh_disable();
164 				sock_prot_dec_use(sk->sk_prot);
165 				sock_prot_inc_use(&tcp_prot);
166 				local_bh_enable();
167 				sk->sk_prot = &tcp_prot;
168 				icsk->icsk_af_ops = &ipv4_specific;
169 				sk->sk_socket->ops = &inet_stream_ops;
170 				sk->sk_family = PF_INET;
171 				tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
172 			} else {
173 				local_bh_disable();
174 				sock_prot_dec_use(sk->sk_prot);
175 				sock_prot_inc_use(&udp_prot);
176 				local_bh_enable();
177 				sk->sk_prot = &udp_prot;
178 				sk->sk_socket->ops = &inet_dgram_ops;
179 				sk->sk_family = PF_INET;
180 			}
181 			opt = xchg(&np->opt, NULL);
182 			if (opt)
183 				sock_kfree_s(sk, opt, opt->tot_len);
184 			pktopt = xchg(&np->pktoptions, NULL);
185 			if (pktopt)
186 				kfree_skb(pktopt);
187 
188 			sk->sk_destruct = inet_sock_destruct;
189 			/*
190 			 * ... and add it to the refcnt debug socks count
191 			 * in the new family. -acme
192 			 */
193 			sk_refcnt_debug_inc(sk);
194 			module_put(THIS_MODULE);
195 			retv = 0;
196 			break;
197 		}
198 		goto e_inval;
199 
200 	case IPV6_V6ONLY:
201 		if (inet_sk(sk)->num)
202 			goto e_inval;
203 		np->ipv6only = valbool;
204 		retv = 0;
205 		break;
206 
207 	case IPV6_RECVPKTINFO:
208 		np->rxopt.bits.rxinfo = valbool;
209 		retv = 0;
210 		break;
211 
212 	case IPV6_2292PKTINFO:
213 		np->rxopt.bits.rxoinfo = valbool;
214 		retv = 0;
215 		break;
216 
217 	case IPV6_RECVHOPLIMIT:
218 		np->rxopt.bits.rxhlim = valbool;
219 		retv = 0;
220 		break;
221 
222 	case IPV6_2292HOPLIMIT:
223 		np->rxopt.bits.rxohlim = valbool;
224 		retv = 0;
225 		break;
226 
227 	case IPV6_RECVRTHDR:
228 		if (val < 0 || val > 2)
229 			goto e_inval;
230 		np->rxopt.bits.srcrt = val;
231 		retv = 0;
232 		break;
233 
234 	case IPV6_2292RTHDR:
235 		if (val < 0 || val > 2)
236 			goto e_inval;
237 		np->rxopt.bits.osrcrt = val;
238 		retv = 0;
239 		break;
240 
241 	case IPV6_RECVHOPOPTS:
242 		np->rxopt.bits.hopopts = valbool;
243 		retv = 0;
244 		break;
245 
246 	case IPV6_2292HOPOPTS:
247 		np->rxopt.bits.ohopopts = valbool;
248 		retv = 0;
249 		break;
250 
251 	case IPV6_RECVDSTOPTS:
252 		np->rxopt.bits.dstopts = valbool;
253 		retv = 0;
254 		break;
255 
256 	case IPV6_2292DSTOPTS:
257 		np->rxopt.bits.odstopts = valbool;
258 		retv = 0;
259 		break;
260 
261 	case IPV6_TCLASS:
262 		if (val < 0 || val > 0xff)
263 			goto e_inval;
264 		np->tclass = val;
265 		retv = 0;
266 		break;
267 
268 	case IPV6_RECVTCLASS:
269 		np->rxopt.bits.rxtclass = valbool;
270 		retv = 0;
271 		break;
272 
273 	case IPV6_FLOWINFO:
274 		np->rxopt.bits.rxflow = valbool;
275 		retv = 0;
276 		break;
277 
278 	case IPV6_HOPOPTS:
279 	case IPV6_RTHDRDSTOPTS:
280 	case IPV6_RTHDR:
281 	case IPV6_DSTOPTS:
282 	{
283 		struct ipv6_txoptions *opt;
284 		if (optlen == 0)
285 			optval = NULL;
286 
287 		/* hop-by-hop / destination options are privileged option */
288 		retv = -EPERM;
289 		if (optname != IPV6_RTHDR && !capable(CAP_NET_RAW))
290 			break;
291 
292 		retv = -EINVAL;
293 		if (optlen & 0x7 || optlen > 8 * 255)
294 			break;
295 
296 		opt = ipv6_renew_options(sk, np->opt, optname,
297 					 (struct ipv6_opt_hdr __user *)optval,
298 					 optlen);
299 		if (IS_ERR(opt)) {
300 			retv = PTR_ERR(opt);
301 			break;
302 		}
303 
304 		/* routing header option needs extra check */
305 		if (optname == IPV6_RTHDR && opt->srcrt) {
306 			struct ipv6_rt_hdr *rthdr = opt->srcrt;
307 			if (rthdr->type)
308 				goto sticky_done;
309 			if ((rthdr->hdrlen & 1) ||
310 			    (rthdr->hdrlen >> 1) != rthdr->segments_left)
311 				goto sticky_done;
312 		}
313 
314 		retv = 0;
315 		if (inet_sk(sk)->is_icsk) {
316 			if (opt) {
317 				struct inet_connection_sock *icsk = inet_csk(sk);
318 				if (!((1 << sk->sk_state) &
319 				      (TCPF_LISTEN | TCPF_CLOSE))
320 				    && inet_sk(sk)->daddr != LOOPBACK4_IPV6) {
321 					icsk->icsk_ext_hdr_len =
322 						opt->opt_flen + opt->opt_nflen;
323 					icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
324 				}
325 			}
326 			opt = xchg(&np->opt, opt);
327 			sk_dst_reset(sk);
328 		} else {
329 			write_lock(&sk->sk_dst_lock);
330 			opt = xchg(&np->opt, opt);
331 			write_unlock(&sk->sk_dst_lock);
332 			sk_dst_reset(sk);
333 		}
334 sticky_done:
335 		if (opt)
336 			sock_kfree_s(sk, opt, opt->tot_len);
337 		break;
338 	}
339 
340 	case IPV6_2292PKTOPTIONS:
341 	{
342 		struct ipv6_txoptions *opt = NULL;
343 		struct msghdr msg;
344 		struct flowi fl;
345 		int junk;
346 
347 		fl.fl6_flowlabel = 0;
348 		fl.oif = sk->sk_bound_dev_if;
349 
350 		if (optlen == 0)
351 			goto update;
352 
353 		/* 1K is probably excessive
354 		 * 1K is surely not enough, 2K per standard header is 16K.
355 		 */
356 		retv = -EINVAL;
357 		if (optlen > 64*1024)
358 			break;
359 
360 		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
361 		retv = -ENOBUFS;
362 		if (opt == NULL)
363 			break;
364 
365 		memset(opt, 0, sizeof(*opt));
366 		opt->tot_len = sizeof(*opt) + optlen;
367 		retv = -EFAULT;
368 		if (copy_from_user(opt+1, optval, optlen))
369 			goto done;
370 
371 		msg.msg_controllen = optlen;
372 		msg.msg_control = (void*)(opt+1);
373 
374 		retv = datagram_send_ctl(&msg, &fl, opt, &junk, &junk);
375 		if (retv)
376 			goto done;
377 update:
378 		retv = 0;
379 		if (inet_sk(sk)->is_icsk) {
380 			if (opt) {
381 				struct inet_connection_sock *icsk = inet_csk(sk);
382 				if (!((1 << sk->sk_state) &
383 				      (TCPF_LISTEN | TCPF_CLOSE))
384 				    && inet_sk(sk)->daddr != LOOPBACK4_IPV6) {
385 					icsk->icsk_ext_hdr_len =
386 						opt->opt_flen + opt->opt_nflen;
387 					icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
388 				}
389 			}
390 			opt = xchg(&np->opt, opt);
391 			sk_dst_reset(sk);
392 		} else {
393 			write_lock(&sk->sk_dst_lock);
394 			opt = xchg(&np->opt, opt);
395 			write_unlock(&sk->sk_dst_lock);
396 			sk_dst_reset(sk);
397 		}
398 
399 done:
400 		if (opt)
401 			sock_kfree_s(sk, opt, opt->tot_len);
402 		break;
403 	}
404 	case IPV6_UNICAST_HOPS:
405 		if (val > 255 || val < -1)
406 			goto e_inval;
407 		np->hop_limit = val;
408 		retv = 0;
409 		break;
410 
411 	case IPV6_MULTICAST_HOPS:
412 		if (sk->sk_type == SOCK_STREAM)
413 			goto e_inval;
414 		if (val > 255 || val < -1)
415 			goto e_inval;
416 		np->mcast_hops = val;
417 		retv = 0;
418 		break;
419 
420 	case IPV6_MULTICAST_LOOP:
421 		np->mc_loop = valbool;
422 		retv = 0;
423 		break;
424 
425 	case IPV6_MULTICAST_IF:
426 		if (sk->sk_type == SOCK_STREAM)
427 			goto e_inval;
428 		if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val)
429 			goto e_inval;
430 
431 		if (__dev_get_by_index(val) == NULL) {
432 			retv = -ENODEV;
433 			break;
434 		}
435 		np->mcast_oif = val;
436 		retv = 0;
437 		break;
438 	case IPV6_ADD_MEMBERSHIP:
439 	case IPV6_DROP_MEMBERSHIP:
440 	{
441 		struct ipv6_mreq mreq;
442 
443 		retv = -EFAULT;
444 		if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
445 			break;
446 
447 		if (optname == IPV6_ADD_MEMBERSHIP)
448 			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
449 		else
450 			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
451 		break;
452 	}
453 	case IPV6_JOIN_ANYCAST:
454 	case IPV6_LEAVE_ANYCAST:
455 	{
456 		struct ipv6_mreq mreq;
457 
458 		if (optlen != sizeof(struct ipv6_mreq))
459 			goto e_inval;
460 
461 		retv = -EFAULT;
462 		if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
463 			break;
464 
465 		if (optname == IPV6_JOIN_ANYCAST)
466 			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
467 		else
468 			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
469 		break;
470 	}
471 	case MCAST_JOIN_GROUP:
472 	case MCAST_LEAVE_GROUP:
473 	{
474 		struct group_req greq;
475 		struct sockaddr_in6 *psin6;
476 
477 		retv = -EFAULT;
478 		if (copy_from_user(&greq, optval, sizeof(struct group_req)))
479 			break;
480 		if (greq.gr_group.ss_family != AF_INET6) {
481 			retv = -EADDRNOTAVAIL;
482 			break;
483 		}
484 		psin6 = (struct sockaddr_in6 *)&greq.gr_group;
485 		if (optname == MCAST_JOIN_GROUP)
486 			retv = ipv6_sock_mc_join(sk, greq.gr_interface,
487 				&psin6->sin6_addr);
488 		else
489 			retv = ipv6_sock_mc_drop(sk, greq.gr_interface,
490 				&psin6->sin6_addr);
491 		break;
492 	}
493 	case MCAST_JOIN_SOURCE_GROUP:
494 	case MCAST_LEAVE_SOURCE_GROUP:
495 	case MCAST_BLOCK_SOURCE:
496 	case MCAST_UNBLOCK_SOURCE:
497 	{
498 		struct group_source_req greqs;
499 		int omode, add;
500 
501 		if (optlen != sizeof(struct group_source_req))
502 			goto e_inval;
503 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
504 			retv = -EFAULT;
505 			break;
506 		}
507 		if (greqs.gsr_group.ss_family != AF_INET6 ||
508 		    greqs.gsr_source.ss_family != AF_INET6) {
509 			retv = -EADDRNOTAVAIL;
510 			break;
511 		}
512 		if (optname == MCAST_BLOCK_SOURCE) {
513 			omode = MCAST_EXCLUDE;
514 			add = 1;
515 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
516 			omode = MCAST_EXCLUDE;
517 			add = 0;
518 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
519 			struct sockaddr_in6 *psin6;
520 
521 			psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
522 			retv = ipv6_sock_mc_join(sk, greqs.gsr_interface,
523 				&psin6->sin6_addr);
524 			/* prior join w/ different source is ok */
525 			if (retv && retv != -EADDRINUSE)
526 				break;
527 			omode = MCAST_INCLUDE;
528 			add = 1;
529 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
530 			omode = MCAST_INCLUDE;
531 			add = 0;
532 		}
533 		retv = ip6_mc_source(add, omode, sk, &greqs);
534 		break;
535 	}
536 	case MCAST_MSFILTER:
537 	{
538 		extern int sysctl_mld_max_msf;
539 		struct group_filter *gsf;
540 
541 		if (optlen < GROUP_FILTER_SIZE(0))
542 			goto e_inval;
543 		if (optlen > sysctl_optmem_max) {
544 			retv = -ENOBUFS;
545 			break;
546 		}
547 		gsf = kmalloc(optlen,GFP_KERNEL);
548 		if (gsf == 0) {
549 			retv = -ENOBUFS;
550 			break;
551 		}
552 		retv = -EFAULT;
553 		if (copy_from_user(gsf, optval, optlen)) {
554 			kfree(gsf);
555 			break;
556 		}
557 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
558 		if (gsf->gf_numsrc >= 0x1ffffffU ||
559 		    gsf->gf_numsrc > sysctl_mld_max_msf) {
560 			kfree(gsf);
561 			retv = -ENOBUFS;
562 			break;
563 		}
564 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
565 			kfree(gsf);
566 			retv = -EINVAL;
567 			break;
568 		}
569 		retv = ip6_mc_msfilter(sk, gsf);
570 		kfree(gsf);
571 
572 		break;
573 	}
574 	case IPV6_ROUTER_ALERT:
575 		retv = ip6_ra_control(sk, val, NULL);
576 		break;
577 	case IPV6_MTU_DISCOVER:
578 		if (val<0 || val>2)
579 			goto e_inval;
580 		np->pmtudisc = val;
581 		retv = 0;
582 		break;
583 	case IPV6_MTU:
584 		if (val && val < IPV6_MIN_MTU)
585 			goto e_inval;
586 		np->frag_size = val;
587 		retv = 0;
588 		break;
589 	case IPV6_RECVERR:
590 		np->recverr = valbool;
591 		if (!val)
592 			skb_queue_purge(&sk->sk_error_queue);
593 		retv = 0;
594 		break;
595 	case IPV6_FLOWINFO_SEND:
596 		np->sndflow = valbool;
597 		retv = 0;
598 		break;
599 	case IPV6_FLOWLABEL_MGR:
600 		retv = ipv6_flowlabel_opt(sk, optval, optlen);
601 		break;
602 	case IPV6_IPSEC_POLICY:
603 	case IPV6_XFRM_POLICY:
604 		retv = -EPERM;
605 		if (!capable(CAP_NET_ADMIN))
606 			break;
607 		retv = xfrm_user_policy(sk, optname, optval, optlen);
608 		break;
609 
610 	}
611 	release_sock(sk);
612 
613 	return retv;
614 
615 e_inval:
616 	release_sock(sk);
617 	return -EINVAL;
618 }
619 
620 int ipv6_setsockopt(struct sock *sk, int level, int optname,
621 		    char __user *optval, int optlen)
622 {
623 	int err;
624 
625 	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
626 		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
627 
628 	if (level != SOL_IPV6)
629 		return -ENOPROTOOPT;
630 
631 	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
632 #ifdef CONFIG_NETFILTER
633 	/* we need to exclude all possible ENOPROTOOPTs except default case */
634 	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
635 			optname != IPV6_XFRM_POLICY) {
636 		lock_sock(sk);
637 		err = nf_setsockopt(sk, PF_INET6, optname, optval,
638 				optlen);
639 		release_sock(sk);
640 	}
641 #endif
642 	return err;
643 }
644 
645 
646 #ifdef CONFIG_COMPAT
647 int compat_ipv6_setsockopt(struct sock *sk, int level, int optname,
648 			   char __user *optval, int optlen)
649 {
650 	int err;
651 
652 	if (level == SOL_IP && sk->sk_type != SOCK_RAW) {
653 		if (udp_prot.compat_setsockopt != NULL)
654 			return udp_prot.compat_setsockopt(sk, level, optname,
655 							  optval, optlen);
656 		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
657 	}
658 
659 	if (level != SOL_IPV6)
660 		return -ENOPROTOOPT;
661 
662 	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
663 #ifdef CONFIG_NETFILTER
664 	/* we need to exclude all possible ENOPROTOOPTs except default case */
665 	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
666 	    optname != IPV6_XFRM_POLICY) {
667 		lock_sock(sk);
668 		err = compat_nf_setsockopt(sk, PF_INET6, optname,
669 					   optval, optlen);
670 		release_sock(sk);
671 	}
672 #endif
673 	return err;
674 }
675 
676 EXPORT_SYMBOL(compat_ipv6_setsockopt);
677 #endif
678 
679 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_opt_hdr *hdr,
680 				  char __user *optval, int len)
681 {
682 	if (!hdr)
683 		return 0;
684 	len = min_t(int, len, ipv6_optlen(hdr));
685 	if (copy_to_user(optval, hdr, ipv6_optlen(hdr)))
686 		return -EFAULT;
687 	return len;
688 }
689 
690 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
691 		    char __user *optval, int __user *optlen)
692 {
693 	struct ipv6_pinfo *np = inet6_sk(sk);
694 	int len;
695 	int val;
696 
697 	if (get_user(len, optlen))
698 		return -EFAULT;
699 	switch (optname) {
700 	case IPV6_ADDRFORM:
701 		if (sk->sk_protocol != IPPROTO_UDP &&
702 		    sk->sk_protocol != IPPROTO_TCP)
703 			return -EINVAL;
704 		if (sk->sk_state != TCP_ESTABLISHED)
705 			return -ENOTCONN;
706 		val = sk->sk_family;
707 		break;
708 	case MCAST_MSFILTER:
709 	{
710 		struct group_filter gsf;
711 		int err;
712 
713 		if (len < GROUP_FILTER_SIZE(0))
714 			return -EINVAL;
715 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0)))
716 			return -EFAULT;
717 		lock_sock(sk);
718 		err = ip6_mc_msfget(sk, &gsf,
719 			(struct group_filter __user *)optval, optlen);
720 		release_sock(sk);
721 		return err;
722 	}
723 
724 	case IPV6_2292PKTOPTIONS:
725 	{
726 		struct msghdr msg;
727 		struct sk_buff *skb;
728 
729 		if (sk->sk_type != SOCK_STREAM)
730 			return -ENOPROTOOPT;
731 
732 		msg.msg_control = optval;
733 		msg.msg_controllen = len;
734 		msg.msg_flags = 0;
735 
736 		lock_sock(sk);
737 		skb = np->pktoptions;
738 		if (skb)
739 			atomic_inc(&skb->users);
740 		release_sock(sk);
741 
742 		if (skb) {
743 			int err = datagram_recv_ctl(sk, &msg, skb);
744 			kfree_skb(skb);
745 			if (err)
746 				return err;
747 		} else {
748 			if (np->rxopt.bits.rxinfo) {
749 				struct in6_pktinfo src_info;
750 				src_info.ipi6_ifindex = np->mcast_oif;
751 				ipv6_addr_copy(&src_info.ipi6_addr, &np->daddr);
752 				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
753 			}
754 			if (np->rxopt.bits.rxhlim) {
755 				int hlim = np->mcast_hops;
756 				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
757 			}
758 			if (np->rxopt.bits.rxoinfo) {
759 				struct in6_pktinfo src_info;
760 				src_info.ipi6_ifindex = np->mcast_oif;
761 				ipv6_addr_copy(&src_info.ipi6_addr, &np->daddr);
762 				put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
763 			}
764 			if (np->rxopt.bits.rxohlim) {
765 				int hlim = np->mcast_hops;
766 				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
767 			}
768 		}
769 		len -= msg.msg_controllen;
770 		return put_user(len, optlen);
771 	}
772 	case IPV6_MTU:
773 	{
774 		struct dst_entry *dst;
775 		val = 0;
776 		lock_sock(sk);
777 		dst = sk_dst_get(sk);
778 		if (dst) {
779 			val = dst_mtu(dst);
780 			dst_release(dst);
781 		}
782 		release_sock(sk);
783 		if (!val)
784 			return -ENOTCONN;
785 		break;
786 	}
787 
788 	case IPV6_V6ONLY:
789 		val = np->ipv6only;
790 		break;
791 
792 	case IPV6_RECVPKTINFO:
793 		val = np->rxopt.bits.rxinfo;
794 		break;
795 
796 	case IPV6_2292PKTINFO:
797 		val = np->rxopt.bits.rxoinfo;
798 		break;
799 
800 	case IPV6_RECVHOPLIMIT:
801 		val = np->rxopt.bits.rxhlim;
802 		break;
803 
804 	case IPV6_2292HOPLIMIT:
805 		val = np->rxopt.bits.rxohlim;
806 		break;
807 
808 	case IPV6_RECVRTHDR:
809 		val = np->rxopt.bits.srcrt;
810 		break;
811 
812 	case IPV6_2292RTHDR:
813 		val = np->rxopt.bits.osrcrt;
814 		break;
815 
816 	case IPV6_HOPOPTS:
817 	case IPV6_RTHDRDSTOPTS:
818 	case IPV6_RTHDR:
819 	case IPV6_DSTOPTS:
820 	{
821 
822 		lock_sock(sk);
823 		len = ipv6_getsockopt_sticky(sk, np->opt->hopopt,
824 					     optval, len);
825 		release_sock(sk);
826 		return put_user(len, optlen);
827 	}
828 
829 	case IPV6_RECVHOPOPTS:
830 		val = np->rxopt.bits.hopopts;
831 		break;
832 
833 	case IPV6_2292HOPOPTS:
834 		val = np->rxopt.bits.ohopopts;
835 		break;
836 
837 	case IPV6_RECVDSTOPTS:
838 		val = np->rxopt.bits.dstopts;
839 		break;
840 
841 	case IPV6_2292DSTOPTS:
842 		val = np->rxopt.bits.odstopts;
843 		break;
844 
845 	case IPV6_TCLASS:
846 		val = np->tclass;
847 		break;
848 
849 	case IPV6_RECVTCLASS:
850 		val = np->rxopt.bits.rxtclass;
851 		break;
852 
853 	case IPV6_FLOWINFO:
854 		val = np->rxopt.bits.rxflow;
855 		break;
856 
857 	case IPV6_UNICAST_HOPS:
858 		val = np->hop_limit;
859 		break;
860 
861 	case IPV6_MULTICAST_HOPS:
862 		val = np->mcast_hops;
863 		break;
864 
865 	case IPV6_MULTICAST_LOOP:
866 		val = np->mc_loop;
867 		break;
868 
869 	case IPV6_MULTICAST_IF:
870 		val = np->mcast_oif;
871 		break;
872 
873 	case IPV6_MTU_DISCOVER:
874 		val = np->pmtudisc;
875 		break;
876 
877 	case IPV6_RECVERR:
878 		val = np->recverr;
879 		break;
880 
881 	case IPV6_FLOWINFO_SEND:
882 		val = np->sndflow;
883 		break;
884 
885 	default:
886 		return -EINVAL;
887 	}
888 	len = min_t(unsigned int, sizeof(int), len);
889 	if(put_user(len, optlen))
890 		return -EFAULT;
891 	if(copy_to_user(optval,&val,len))
892 		return -EFAULT;
893 	return 0;
894 }
895 
896 int ipv6_getsockopt(struct sock *sk, int level, int optname,
897 		    char __user *optval, int __user *optlen)
898 {
899 	int err;
900 
901 	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
902 		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
903 
904 	if(level != SOL_IPV6)
905 		return -ENOPROTOOPT;
906 
907 	err = do_ipv6_getsockopt(sk, level, optname, optval, optlen);
908 #ifdef CONFIG_NETFILTER
909 	/* we need to exclude all possible EINVALs except default case */
910 	if (err == -EINVAL && optname != IPV6_ADDRFORM &&
911 			optname != MCAST_MSFILTER) {
912 		int len;
913 
914 		if (get_user(len, optlen))
915 			return -EFAULT;
916 
917 		lock_sock(sk);
918 		err = nf_getsockopt(sk, PF_INET6, optname, optval,
919 				&len);
920 		release_sock(sk);
921 		if (err >= 0)
922 			err = put_user(len, optlen);
923 	}
924 #endif
925 	return err;
926 }
927 
928 #ifdef CONFIG_COMPAT
929 int compat_ipv6_getsockopt(struct sock *sk, int level, int optname,
930 			   char __user *optval, int __user *optlen)
931 {
932 	int err;
933 
934 	if (level == SOL_IP && sk->sk_type != SOCK_RAW) {
935 		if (udp_prot.compat_getsockopt != NULL)
936 			return udp_prot.compat_getsockopt(sk, level, optname,
937 							  optval, optlen);
938 		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
939 	}
940 
941 	if (level != SOL_IPV6)
942 		return -ENOPROTOOPT;
943 
944 	err = do_ipv6_getsockopt(sk, level, optname, optval, optlen);
945 #ifdef CONFIG_NETFILTER
946 	/* we need to exclude all possible EINVALs except default case */
947 	if (err == -EINVAL && optname != IPV6_ADDRFORM &&
948 			optname != MCAST_MSFILTER) {
949 		int len;
950 
951 		if (get_user(len, optlen))
952 			return -EFAULT;
953 
954 		lock_sock(sk);
955 		err = compat_nf_getsockopt(sk, PF_INET6,
956 					   optname, optval, &len);
957 		release_sock(sk);
958 		if (err >= 0)
959 			err = put_user(len, optlen);
960 	}
961 #endif
962 	return err;
963 }
964 
965 EXPORT_SYMBOL(compat_ipv6_getsockopt);
966 #endif
967 
968 void __init ipv6_packet_init(void)
969 {
970 	dev_add_pack(&ipv6_packet_type);
971 }
972 
973 void ipv6_packet_cleanup(void)
974 {
975 	dev_remove_pack(&ipv6_packet_type);
976 }
977