1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *	IPv6 BSD socket options interface
4 *	Linux INET6 implementation
5 *
6 *	Authors:
7 *	Pedro Roque		<roque@di.fc.ul.pt>
8 *
9 *	Based on linux/net/ipv4/ip_sockglue.c
10 *
11 *	FIXME: Make the setsockopt code POSIX compliant: That is
12 *
13 *	o	Truncate getsockopt returns
14 *	o	Return an optlen of the truncated length if need be
15 *
16 *	Changes:
17 *	David L Stevens <dlstevens@us.ibm.com>:
18 *		- added multicast source filtering API for MLDv2
19 */
20
21#include <linux/module.h>
22#include <linux/capability.h>
23#include <linux/errno.h>
24#include <linux/types.h>
25#include <linux/socket.h>
26#include <linux/sockios.h>
27#include <linux/net.h>
28#include <linux/in6.h>
29#include <linux/mroute6.h>
30#include <linux/netdevice.h>
31#include <linux/if_arp.h>
32#include <linux/init.h>
33#include <linux/sysctl.h>
34#include <linux/netfilter.h>
35#include <linux/slab.h>
36
37#include <net/sock.h>
38#include <net/snmp.h>
39#include <net/ipv6.h>
40#include <net/ndisc.h>
41#include <net/protocol.h>
42#include <net/transp_v6.h>
43#include <net/ip6_route.h>
44#include <net/addrconf.h>
45#include <net/inet_common.h>
46#include <net/tcp.h>
47#include <net/udp.h>
48#include <net/udplite.h>
49#include <net/xfrm.h>
50#include <net/compat.h>
51#include <net/seg6.h>
52
53#include <linux/uaccess.h>
54
55struct ip6_ra_chain *ip6_ra_chain;
56DEFINE_RWLOCK(ip6_ra_lock);
57
58DEFINE_STATIC_KEY_FALSE(ip6_min_hopcount);
59
60int ip6_ra_control(struct sock *sk, int sel)
61{
62	struct ip6_ra_chain *ra, *new_ra, **rap;
63
64	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
65	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
66		return -ENOPROTOOPT;
67
68	new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
69	if (sel >= 0 && !new_ra)
70		return -ENOMEM;
71
72	write_lock_bh(&ip6_ra_lock);
73	for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
74		if (ra->sk == sk) {
75			if (sel >= 0) {
76				write_unlock_bh(&ip6_ra_lock);
77				kfree(new_ra);
78				return -EADDRINUSE;
79			}
80
81			*rap = ra->next;
82			write_unlock_bh(&ip6_ra_lock);
83
84			sock_put(sk);
85			kfree(ra);
86			return 0;
87		}
88	}
89	if (!new_ra) {
90		write_unlock_bh(&ip6_ra_lock);
91		return -ENOBUFS;
92	}
93	new_ra->sk = sk;
94	new_ra->sel = sel;
95	new_ra->next = ra;
96	*rap = new_ra;
97	sock_hold(sk);
98	write_unlock_bh(&ip6_ra_lock);
99	return 0;
100}
101
102struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
103					   struct ipv6_txoptions *opt)
104{
105	if (inet_test_bit(IS_ICSK, sk)) {
106		if (opt &&
107		    !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
108		    inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
109			struct inet_connection_sock *icsk = inet_csk(sk);
110			icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
111			icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
112		}
113	}
114	opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
115		   opt);
116	sk_dst_reset(sk);
117
118	return opt;
119}
120
121static bool setsockopt_needs_rtnl(int optname)
122{
123	switch (optname) {
124	case IPV6_ADDRFORM:
125	case IPV6_ADD_MEMBERSHIP:
126	case IPV6_DROP_MEMBERSHIP:
127	case IPV6_JOIN_ANYCAST:
128	case IPV6_LEAVE_ANYCAST:
129	case MCAST_JOIN_GROUP:
130	case MCAST_LEAVE_GROUP:
131	case MCAST_JOIN_SOURCE_GROUP:
132	case MCAST_LEAVE_SOURCE_GROUP:
133	case MCAST_BLOCK_SOURCE:
134	case MCAST_UNBLOCK_SOURCE:
135	case MCAST_MSFILTER:
136		return true;
137	}
138	return false;
139}
140
141static int copy_group_source_from_sockptr(struct group_source_req *greqs,
142		sockptr_t optval, int optlen)
143{
144	if (in_compat_syscall()) {
145		struct compat_group_source_req gr32;
146
147		if (optlen < sizeof(gr32))
148			return -EINVAL;
149		if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
150			return -EFAULT;
151		greqs->gsr_interface = gr32.gsr_interface;
152		greqs->gsr_group = gr32.gsr_group;
153		greqs->gsr_source = gr32.gsr_source;
154	} else {
155		if (optlen < sizeof(*greqs))
156			return -EINVAL;
157		if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
158			return -EFAULT;
159	}
160
161	return 0;
162}
163
164static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
165		sockptr_t optval, int optlen)
166{
167	struct group_source_req greqs;
168	int omode, add;
169	int ret;
170
171	ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
172	if (ret)
173		return ret;
174
175	if (greqs.gsr_group.ss_family != AF_INET6 ||
176	    greqs.gsr_source.ss_family != AF_INET6)
177		return -EADDRNOTAVAIL;
178
179	if (optname == MCAST_BLOCK_SOURCE) {
180		omode = MCAST_EXCLUDE;
181		add = 1;
182	} else if (optname == MCAST_UNBLOCK_SOURCE) {
183		omode = MCAST_EXCLUDE;
184		add = 0;
185	} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
186		struct sockaddr_in6 *psin6;
187		int retv;
188
189		psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
190		retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
191					     &psin6->sin6_addr,
192					     MCAST_INCLUDE);
193		/* prior join w/ different source is ok */
194		if (retv && retv != -EADDRINUSE)
195			return retv;
196		omode = MCAST_INCLUDE;
197		add = 1;
198	} else /* MCAST_LEAVE_SOURCE_GROUP */ {
199		omode = MCAST_INCLUDE;
200		add = 0;
201	}
202	return ip6_mc_source(add, omode, sk, &greqs);
203}
204
205static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
206		int optlen)
207{
208	struct group_filter *gsf;
209	int ret;
210
211	if (optlen < GROUP_FILTER_SIZE(0))
212		return -EINVAL;
213	if (optlen > READ_ONCE(sysctl_optmem_max))
214		return -ENOBUFS;
215
216	gsf = memdup_sockptr(optval, optlen);
217	if (IS_ERR(gsf))
218		return PTR_ERR(gsf);
219
220	/* numsrc >= (4G-140)/128 overflow in 32 bits */
221	ret = -ENOBUFS;
222	if (gsf->gf_numsrc >= 0x1ffffffU ||
223	    gsf->gf_numsrc > sysctl_mld_max_msf)
224		goto out_free_gsf;
225
226	ret = -EINVAL;
227	if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
228		goto out_free_gsf;
229
230	ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
231out_free_gsf:
232	kfree(gsf);
233	return ret;
234}
235
236static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
237		int optlen)
238{
239	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
240	struct compat_group_filter *gf32;
241	void *p;
242	int ret;
243	int n;
244
245	if (optlen < size0)
246		return -EINVAL;
247	if (optlen > READ_ONCE(sysctl_optmem_max) - 4)
248		return -ENOBUFS;
249
250	p = kmalloc(optlen + 4, GFP_KERNEL);
251	if (!p)
252		return -ENOMEM;
253
254	gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
255	ret = -EFAULT;
256	if (copy_from_sockptr(gf32, optval, optlen))
257		goto out_free_p;
258
259	/* numsrc >= (4G-140)/128 overflow in 32 bits */
260	ret = -ENOBUFS;
261	n = gf32->gf_numsrc;
262	if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
263		goto out_free_p;
264
265	ret = -EINVAL;
266	if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
267		goto out_free_p;
268
269	ret = ip6_mc_msfilter(sk, &(struct group_filter){
270			.gf_interface = gf32->gf_interface,
271			.gf_group = gf32->gf_group,
272			.gf_fmode = gf32->gf_fmode,
273			.gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
274
275out_free_p:
276	kfree(p);
277	return ret;
278}
279
280static int ipv6_mcast_join_leave(struct sock *sk, int optname,
281		sockptr_t optval, int optlen)
282{
283	struct sockaddr_in6 *psin6;
284	struct group_req greq;
285
286	if (optlen < sizeof(greq))
287		return -EINVAL;
288	if (copy_from_sockptr(&greq, optval, sizeof(greq)))
289		return -EFAULT;
290
291	if (greq.gr_group.ss_family != AF_INET6)
292		return -EADDRNOTAVAIL;
293	psin6 = (struct sockaddr_in6 *)&greq.gr_group;
294	if (optname == MCAST_JOIN_GROUP)
295		return ipv6_sock_mc_join(sk, greq.gr_interface,
296					 &psin6->sin6_addr);
297	return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
298}
299
300static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
301		sockptr_t optval, int optlen)
302{
303	struct compat_group_req gr32;
304	struct sockaddr_in6 *psin6;
305
306	if (optlen < sizeof(gr32))
307		return -EINVAL;
308	if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
309		return -EFAULT;
310
311	if (gr32.gr_group.ss_family != AF_INET6)
312		return -EADDRNOTAVAIL;
313	psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
314	if (optname == MCAST_JOIN_GROUP)
315		return ipv6_sock_mc_join(sk, gr32.gr_interface,
316					&psin6->sin6_addr);
317	return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
318}
319
320static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
321		int optlen)
322{
323	struct ipv6_pinfo *np = inet6_sk(sk);
324	struct ipv6_opt_hdr *new = NULL;
325	struct net *net = sock_net(sk);
326	struct ipv6_txoptions *opt;
327	int err;
328
329	/* hop-by-hop / destination options are privileged option */
330	if (optname != IPV6_RTHDR && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW))
331		return -EPERM;
332
333	/* remove any sticky options header with a zero option
334	 * length, per RFC3542.
335	 */
336	if (optlen > 0) {
337		if (sockptr_is_null(optval))
338			return -EINVAL;
339		if (optlen < sizeof(struct ipv6_opt_hdr) ||
340		    optlen & 0x7 ||
341		    optlen > 8 * 255)
342			return -EINVAL;
343
344		new = memdup_sockptr(optval, optlen);
345		if (IS_ERR(new))
346			return PTR_ERR(new);
347		if (unlikely(ipv6_optlen(new) > optlen)) {
348			kfree(new);
349			return -EINVAL;
350		}
351	}
352
353	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
354	opt = ipv6_renew_options(sk, opt, optname, new);
355	kfree(new);
356	if (IS_ERR(opt))
357		return PTR_ERR(opt);
358
359	/* routing header option needs extra check */
360	err = -EINVAL;
361	if (optname == IPV6_RTHDR && opt && opt->srcrt) {
362		struct ipv6_rt_hdr *rthdr = opt->srcrt;
363		switch (rthdr->type) {
364#if IS_ENABLED(CONFIG_IPV6_MIP6)
365		case IPV6_SRCRT_TYPE_2:
366			if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
367				goto sticky_done;
368			break;
369#endif
370		case IPV6_SRCRT_TYPE_4:
371		{
372			struct ipv6_sr_hdr *srh =
373				(struct ipv6_sr_hdr *)opt->srcrt;
374
375			if (!seg6_validate_srh(srh, optlen, false))
376				goto sticky_done;
377			break;
378		}
379		default:
380			goto sticky_done;
381		}
382	}
383
384	err = 0;
385	opt = ipv6_update_options(sk, opt);
386sticky_done:
387	if (opt) {
388		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
389		txopt_put(opt);
390	}
391	return err;
392}
393
394int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
395		       sockptr_t optval, unsigned int optlen)
396{
397	struct ipv6_pinfo *np = inet6_sk(sk);
398	struct net *net = sock_net(sk);
399	int val, valbool;
400	int retv = -ENOPROTOOPT;
401	bool needs_rtnl = setsockopt_needs_rtnl(optname);
402
403	if (sockptr_is_null(optval))
404		val = 0;
405	else {
406		if (optlen >= sizeof(int)) {
407			if (copy_from_sockptr(&val, optval, sizeof(val)))
408				return -EFAULT;
409		} else
410			val = 0;
411	}
412
413	valbool = (val != 0);
414
415	if (ip6_mroute_opt(optname))
416		return ip6_mroute_setsockopt(sk, optname, optval, optlen);
417
418	if (needs_rtnl)
419		rtnl_lock();
420	sockopt_lock_sock(sk);
421
422	/* Another thread has converted the socket into IPv4 with
423	 * IPV6_ADDRFORM concurrently.
424	 */
425	if (unlikely(sk->sk_family != AF_INET6))
426		goto unlock;
427
428	switch (optname) {
429
430	case IPV6_ADDRFORM:
431		if (optlen < sizeof(int))
432			goto e_inval;
433		if (val == PF_INET) {
434			if (sk->sk_type == SOCK_RAW)
435				break;
436
437			if (sk->sk_protocol == IPPROTO_UDP ||
438			    sk->sk_protocol == IPPROTO_UDPLITE) {
439				struct udp_sock *up = udp_sk(sk);
440				if (up->pending == AF_INET6) {
441					retv = -EBUSY;
442					break;
443				}
444			} else if (sk->sk_protocol == IPPROTO_TCP) {
445				if (sk->sk_prot != &tcpv6_prot) {
446					retv = -EBUSY;
447					break;
448				}
449			} else {
450				break;
451			}
452
453			if (sk->sk_state != TCP_ESTABLISHED) {
454				retv = -ENOTCONN;
455				break;
456			}
457
458			if (ipv6_only_sock(sk) ||
459			    !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
460				retv = -EADDRNOTAVAIL;
461				break;
462			}
463
464			__ipv6_sock_mc_close(sk);
465			__ipv6_sock_ac_close(sk);
466
467			if (sk->sk_protocol == IPPROTO_TCP) {
468				struct inet_connection_sock *icsk = inet_csk(sk);
469
470				sock_prot_inuse_add(net, sk->sk_prot, -1);
471				sock_prot_inuse_add(net, &tcp_prot, 1);
472
473				/* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */
474				WRITE_ONCE(sk->sk_prot, &tcp_prot);
475				/* Paired with READ_ONCE() in tcp_(get|set)sockopt() */
476				WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific);
477				WRITE_ONCE(sk->sk_socket->ops, &inet_stream_ops);
478				WRITE_ONCE(sk->sk_family, PF_INET);
479				tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
480			} else {
481				struct proto *prot = &udp_prot;
482
483				if (sk->sk_protocol == IPPROTO_UDPLITE)
484					prot = &udplite_prot;
485
486				sock_prot_inuse_add(net, sk->sk_prot, -1);
487				sock_prot_inuse_add(net, prot, 1);
488
489				/* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */
490				WRITE_ONCE(sk->sk_prot, prot);
491				WRITE_ONCE(sk->sk_socket->ops, &inet_dgram_ops);
492				WRITE_ONCE(sk->sk_family, PF_INET);
493			}
494
495			/* Disable all options not to allocate memory anymore,
496			 * but there is still a race.  See the lockless path
497			 * in udpv6_sendmsg() and ipv6_local_rxpmtu().
498			 */
499			np->rxopt.all = 0;
500
501			inet6_cleanup_sock(sk);
502
503			module_put(THIS_MODULE);
504			retv = 0;
505			break;
506		}
507		goto e_inval;
508
509	case IPV6_V6ONLY:
510		if (optlen < sizeof(int) ||
511		    inet_sk(sk)->inet_num)
512			goto e_inval;
513		sk->sk_ipv6only = valbool;
514		retv = 0;
515		break;
516
517	case IPV6_RECVPKTINFO:
518		if (optlen < sizeof(int))
519			goto e_inval;
520		np->rxopt.bits.rxinfo = valbool;
521		retv = 0;
522		break;
523
524	case IPV6_2292PKTINFO:
525		if (optlen < sizeof(int))
526			goto e_inval;
527		np->rxopt.bits.rxoinfo = valbool;
528		retv = 0;
529		break;
530
531	case IPV6_RECVHOPLIMIT:
532		if (optlen < sizeof(int))
533			goto e_inval;
534		np->rxopt.bits.rxhlim = valbool;
535		retv = 0;
536		break;
537
538	case IPV6_2292HOPLIMIT:
539		if (optlen < sizeof(int))
540			goto e_inval;
541		np->rxopt.bits.rxohlim = valbool;
542		retv = 0;
543		break;
544
545	case IPV6_RECVRTHDR:
546		if (optlen < sizeof(int))
547			goto e_inval;
548		np->rxopt.bits.srcrt = valbool;
549		retv = 0;
550		break;
551
552	case IPV6_2292RTHDR:
553		if (optlen < sizeof(int))
554			goto e_inval;
555		np->rxopt.bits.osrcrt = valbool;
556		retv = 0;
557		break;
558
559	case IPV6_RECVHOPOPTS:
560		if (optlen < sizeof(int))
561			goto e_inval;
562		np->rxopt.bits.hopopts = valbool;
563		retv = 0;
564		break;
565
566	case IPV6_2292HOPOPTS:
567		if (optlen < sizeof(int))
568			goto e_inval;
569		np->rxopt.bits.ohopopts = valbool;
570		retv = 0;
571		break;
572
573	case IPV6_RECVDSTOPTS:
574		if (optlen < sizeof(int))
575			goto e_inval;
576		np->rxopt.bits.dstopts = valbool;
577		retv = 0;
578		break;
579
580	case IPV6_2292DSTOPTS:
581		if (optlen < sizeof(int))
582			goto e_inval;
583		np->rxopt.bits.odstopts = valbool;
584		retv = 0;
585		break;
586
587	case IPV6_TCLASS:
588		if (optlen < sizeof(int))
589			goto e_inval;
590		if (val < -1 || val > 0xff)
591			goto e_inval;
592		/* RFC 3542, 6.5: default traffic class of 0x0 */
593		if (val == -1)
594			val = 0;
595		if (sk->sk_type == SOCK_STREAM) {
596			val &= ~INET_ECN_MASK;
597			val |= np->tclass & INET_ECN_MASK;
598		}
599		if (np->tclass != val) {
600			np->tclass = val;
601			sk_dst_reset(sk);
602		}
603		retv = 0;
604		break;
605
606	case IPV6_RECVTCLASS:
607		if (optlen < sizeof(int))
608			goto e_inval;
609		np->rxopt.bits.rxtclass = valbool;
610		retv = 0;
611		break;
612
613	case IPV6_FLOWINFO:
614		if (optlen < sizeof(int))
615			goto e_inval;
616		np->rxopt.bits.rxflow = valbool;
617		retv = 0;
618		break;
619
620	case IPV6_RECVPATHMTU:
621		if (optlen < sizeof(int))
622			goto e_inval;
623		np->rxopt.bits.rxpmtu = valbool;
624		retv = 0;
625		break;
626
627	case IPV6_TRANSPARENT:
628		if (valbool && !sockopt_ns_capable(net->user_ns, CAP_NET_RAW) &&
629		    !sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN)) {
630			retv = -EPERM;
631			break;
632		}
633		if (optlen < sizeof(int))
634			goto e_inval;
635		/* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
636		inet_assign_bit(TRANSPARENT, sk, valbool);
637		retv = 0;
638		break;
639
640	case IPV6_FREEBIND:
641		if (optlen < sizeof(int))
642			goto e_inval;
643		/* we also don't have a separate freebind bit for IPV6 */
644		inet_assign_bit(FREEBIND, sk, valbool);
645		retv = 0;
646		break;
647
648	case IPV6_RECVORIGDSTADDR:
649		if (optlen < sizeof(int))
650			goto e_inval;
651		np->rxopt.bits.rxorigdstaddr = valbool;
652		retv = 0;
653		break;
654
655	case IPV6_HOPOPTS:
656	case IPV6_RTHDRDSTOPTS:
657	case IPV6_RTHDR:
658	case IPV6_DSTOPTS:
659		retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
660		break;
661
662	case IPV6_PKTINFO:
663	{
664		struct in6_pktinfo pkt;
665
666		if (optlen == 0)
667			goto e_inval;
668		else if (optlen < sizeof(struct in6_pktinfo) ||
669			 sockptr_is_null(optval))
670			goto e_inval;
671
672		if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
673			retv = -EFAULT;
674			break;
675		}
676		if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
677			goto e_inval;
678
679		np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
680		np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
681		retv = 0;
682		break;
683	}
684
685	case IPV6_2292PKTOPTIONS:
686	{
687		struct ipv6_txoptions *opt = NULL;
688		struct msghdr msg;
689		struct flowi6 fl6;
690		struct ipcm6_cookie ipc6;
691
692		memset(&fl6, 0, sizeof(fl6));
693		fl6.flowi6_oif = sk->sk_bound_dev_if;
694		fl6.flowi6_mark = sk->sk_mark;
695
696		if (optlen == 0)
697			goto update;
698
699		/* 1K is probably excessive
700		 * 1K is surely not enough, 2K per standard header is 16K.
701		 */
702		retv = -EINVAL;
703		if (optlen > 64*1024)
704			break;
705
706		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
707		retv = -ENOBUFS;
708		if (!opt)
709			break;
710
711		memset(opt, 0, sizeof(*opt));
712		refcount_set(&opt->refcnt, 1);
713		opt->tot_len = sizeof(*opt) + optlen;
714		retv = -EFAULT;
715		if (copy_from_sockptr(opt + 1, optval, optlen))
716			goto done;
717
718		msg.msg_controllen = optlen;
719		msg.msg_control_is_user = false;
720		msg.msg_control = (void *)(opt+1);
721		ipc6.opt = opt;
722
723		retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
724		if (retv)
725			goto done;
726update:
727		retv = 0;
728		opt = ipv6_update_options(sk, opt);
729done:
730		if (opt) {
731			atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
732			txopt_put(opt);
733		}
734		break;
735	}
736	case IPV6_UNICAST_HOPS:
737		if (optlen < sizeof(int))
738			goto e_inval;
739		if (val > 255 || val < -1)
740			goto e_inval;
741		np->hop_limit = val;
742		retv = 0;
743		break;
744
745	case IPV6_MULTICAST_HOPS:
746		if (sk->sk_type == SOCK_STREAM)
747			break;
748		if (optlen < sizeof(int))
749			goto e_inval;
750		if (val > 255 || val < -1)
751			goto e_inval;
752		np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
753		retv = 0;
754		break;
755
756	case IPV6_MULTICAST_LOOP:
757		if (optlen < sizeof(int))
758			goto e_inval;
759		if (val != valbool)
760			goto e_inval;
761		np->mc_loop = valbool;
762		retv = 0;
763		break;
764
765	case IPV6_UNICAST_IF:
766	{
767		struct net_device *dev = NULL;
768		int ifindex;
769
770		if (optlen != sizeof(int))
771			goto e_inval;
772
773		ifindex = (__force int)ntohl((__force __be32)val);
774		if (ifindex == 0) {
775			np->ucast_oif = 0;
776			retv = 0;
777			break;
778		}
779
780		dev = dev_get_by_index(net, ifindex);
781		retv = -EADDRNOTAVAIL;
782		if (!dev)
783			break;
784		dev_put(dev);
785
786		retv = -EINVAL;
787		if (sk->sk_bound_dev_if)
788			break;
789
790		np->ucast_oif = ifindex;
791		retv = 0;
792		break;
793	}
794
795	case IPV6_MULTICAST_IF:
796		if (sk->sk_type == SOCK_STREAM)
797			break;
798		if (optlen < sizeof(int))
799			goto e_inval;
800
801		if (val) {
802			struct net_device *dev;
803			int midx;
804
805			rcu_read_lock();
806
807			dev = dev_get_by_index_rcu(net, val);
808			if (!dev) {
809				rcu_read_unlock();
810				retv = -ENODEV;
811				break;
812			}
813			midx = l3mdev_master_ifindex_rcu(dev);
814
815			rcu_read_unlock();
816
817			if (sk->sk_bound_dev_if &&
818			    sk->sk_bound_dev_if != val &&
819			    (!midx || midx != sk->sk_bound_dev_if))
820				goto e_inval;
821		}
822		np->mcast_oif = val;
823		retv = 0;
824		break;
825	case IPV6_ADD_MEMBERSHIP:
826	case IPV6_DROP_MEMBERSHIP:
827	{
828		struct ipv6_mreq mreq;
829
830		if (optlen < sizeof(struct ipv6_mreq))
831			goto e_inval;
832
833		retv = -EPROTO;
834		if (inet_test_bit(IS_ICSK, sk))
835			break;
836
837		retv = -EFAULT;
838		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
839			break;
840
841		if (optname == IPV6_ADD_MEMBERSHIP)
842			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
843		else
844			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
845		break;
846	}
847	case IPV6_JOIN_ANYCAST:
848	case IPV6_LEAVE_ANYCAST:
849	{
850		struct ipv6_mreq mreq;
851
852		if (optlen < sizeof(struct ipv6_mreq))
853			goto e_inval;
854
855		retv = -EFAULT;
856		if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
857			break;
858
859		if (optname == IPV6_JOIN_ANYCAST)
860			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
861		else
862			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
863		break;
864	}
865	case IPV6_MULTICAST_ALL:
866		if (optlen < sizeof(int))
867			goto e_inval;
868		np->mc_all = valbool;
869		retv = 0;
870		break;
871
872	case MCAST_JOIN_GROUP:
873	case MCAST_LEAVE_GROUP:
874		if (in_compat_syscall())
875			retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
876							    optlen);
877		else
878			retv = ipv6_mcast_join_leave(sk, optname, optval,
879						     optlen);
880		break;
881	case MCAST_JOIN_SOURCE_GROUP:
882	case MCAST_LEAVE_SOURCE_GROUP:
883	case MCAST_BLOCK_SOURCE:
884	case MCAST_UNBLOCK_SOURCE:
885		retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
886		break;
887	case MCAST_MSFILTER:
888		if (in_compat_syscall())
889			retv = compat_ipv6_set_mcast_msfilter(sk, optval,
890							      optlen);
891		else
892			retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
893		break;
894	case IPV6_ROUTER_ALERT:
895		if (optlen < sizeof(int))
896			goto e_inval;
897		retv = ip6_ra_control(sk, val);
898		break;
899	case IPV6_ROUTER_ALERT_ISOLATE:
900		if (optlen < sizeof(int))
901			goto e_inval;
902		np->rtalert_isolate = valbool;
903		retv = 0;
904		break;
905	case IPV6_MTU_DISCOVER:
906		if (optlen < sizeof(int))
907			goto e_inval;
908		if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
909			goto e_inval;
910		np->pmtudisc = val;
911		retv = 0;
912		break;
913	case IPV6_MTU:
914		if (optlen < sizeof(int))
915			goto e_inval;
916		if (val && val < IPV6_MIN_MTU)
917			goto e_inval;
918		np->frag_size = val;
919		retv = 0;
920		break;
921	case IPV6_RECVERR:
922		if (optlen < sizeof(int))
923			goto e_inval;
924		np->recverr = valbool;
925		if (!val)
926			skb_errqueue_purge(&sk->sk_error_queue);
927		retv = 0;
928		break;
929	case IPV6_FLOWINFO_SEND:
930		if (optlen < sizeof(int))
931			goto e_inval;
932		np->sndflow = valbool;
933		retv = 0;
934		break;
935	case IPV6_FLOWLABEL_MGR:
936		retv = ipv6_flowlabel_opt(sk, optval, optlen);
937		break;
938	case IPV6_IPSEC_POLICY:
939	case IPV6_XFRM_POLICY:
940		retv = -EPERM;
941		if (!sockopt_ns_capable(net->user_ns, CAP_NET_ADMIN))
942			break;
943		retv = xfrm_user_policy(sk, optname, optval, optlen);
944		break;
945
946	case IPV6_ADDR_PREFERENCES:
947		if (optlen < sizeof(int))
948			goto e_inval;
949		retv = __ip6_sock_set_addr_preferences(sk, val);
950		break;
951	case IPV6_MINHOPCOUNT:
952		if (optlen < sizeof(int))
953			goto e_inval;
954		if (val < 0 || val > 255)
955			goto e_inval;
956
957		if (val)
958			static_branch_enable(&ip6_min_hopcount);
959
960		/* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
961		 * while we are changing it.
962		 */
963		WRITE_ONCE(np->min_hopcount, val);
964		retv = 0;
965		break;
966	case IPV6_DONTFRAG:
967		np->dontfrag = valbool;
968		retv = 0;
969		break;
970	case IPV6_AUTOFLOWLABEL:
971		np->autoflowlabel = valbool;
972		np->autoflowlabel_set = 1;
973		retv = 0;
974		break;
975	case IPV6_RECVFRAGSIZE:
976		np->rxopt.bits.recvfragsize = valbool;
977		retv = 0;
978		break;
979	case IPV6_RECVERR_RFC4884:
980		if (optlen < sizeof(int))
981			goto e_inval;
982		if (val < 0 || val > 1)
983			goto e_inval;
984		np->recverr_rfc4884 = valbool;
985		retv = 0;
986		break;
987	}
988
989unlock:
990	sockopt_release_sock(sk);
991	if (needs_rtnl)
992		rtnl_unlock();
993
994	return retv;
995
996e_inval:
997	retv = -EINVAL;
998	goto unlock;
999}
1000
1001int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1002		    unsigned int optlen)
1003{
1004	int err;
1005
1006	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1007		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1008
1009	if (level != SOL_IPV6)
1010		return -ENOPROTOOPT;
1011
1012	err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1013#ifdef CONFIG_NETFILTER
1014	/* we need to exclude all possible ENOPROTOOPTs except default case */
1015	if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1016			optname != IPV6_XFRM_POLICY)
1017		err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1018#endif
1019	return err;
1020}
1021EXPORT_SYMBOL(ipv6_setsockopt);
1022
1023static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1024				  int optname, sockptr_t optval, int len)
1025{
1026	struct ipv6_opt_hdr *hdr;
1027
1028	if (!opt)
1029		return 0;
1030
1031	switch (optname) {
1032	case IPV6_HOPOPTS:
1033		hdr = opt->hopopt;
1034		break;
1035	case IPV6_RTHDRDSTOPTS:
1036		hdr = opt->dst0opt;
1037		break;
1038	case IPV6_RTHDR:
1039		hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1040		break;
1041	case IPV6_DSTOPTS:
1042		hdr = opt->dst1opt;
1043		break;
1044	default:
1045		return -EINVAL;	/* should not happen */
1046	}
1047
1048	if (!hdr)
1049		return 0;
1050
1051	len = min_t(unsigned int, len, ipv6_optlen(hdr));
1052	if (copy_to_sockptr(optval, hdr, len))
1053		return -EFAULT;
1054	return len;
1055}
1056
1057static int ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1058			     sockptr_t optlen, int len)
1059{
1060	const int size0 = offsetof(struct group_filter, gf_slist_flex);
1061	struct group_filter gsf;
1062	int num;
1063	int err;
1064
1065	if (len < size0)
1066		return -EINVAL;
1067	if (copy_from_sockptr(&gsf, optval, size0))
1068		return -EFAULT;
1069	if (gsf.gf_group.ss_family != AF_INET6)
1070		return -EADDRNOTAVAIL;
1071	num = gsf.gf_numsrc;
1072	sockopt_lock_sock(sk);
1073	err = ip6_mc_msfget(sk, &gsf, optval, size0);
1074	if (!err) {
1075		if (num > gsf.gf_numsrc)
1076			num = gsf.gf_numsrc;
1077		len = GROUP_FILTER_SIZE(num);
1078		if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1079		    copy_to_sockptr(optval, &gsf, size0))
1080			err = -EFAULT;
1081	}
1082	sockopt_release_sock(sk);
1083	return err;
1084}
1085
1086static int compat_ipv6_get_msfilter(struct sock *sk, sockptr_t optval,
1087				    sockptr_t optlen, int len)
1088{
1089	const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1090	struct compat_group_filter gf32;
1091	struct group_filter gf;
1092	int err;
1093	int num;
1094
1095	if (len < size0)
1096		return -EINVAL;
1097
1098	if (copy_from_sockptr(&gf32, optval, size0))
1099		return -EFAULT;
1100	gf.gf_interface = gf32.gf_interface;
1101	gf.gf_fmode = gf32.gf_fmode;
1102	num = gf.gf_numsrc = gf32.gf_numsrc;
1103	gf.gf_group = gf32.gf_group;
1104
1105	if (gf.gf_group.ss_family != AF_INET6)
1106		return -EADDRNOTAVAIL;
1107
1108	sockopt_lock_sock(sk);
1109	err = ip6_mc_msfget(sk, &gf, optval, size0);
1110	sockopt_release_sock(sk);
1111	if (err)
1112		return err;
1113	if (num > gf.gf_numsrc)
1114		num = gf.gf_numsrc;
1115	len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1116	if (copy_to_sockptr(optlen, &len, sizeof(int)) ||
1117	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_fmode),
1118				   &gf.gf_fmode, sizeof(gf32.gf_fmode)) ||
1119	    copy_to_sockptr_offset(optval, offsetof(struct compat_group_filter, gf_numsrc),
1120				   &gf.gf_numsrc, sizeof(gf32.gf_numsrc)))
1121		return -EFAULT;
1122	return 0;
1123}
1124
1125int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1126		       sockptr_t optval, sockptr_t optlen)
1127{
1128	struct ipv6_pinfo *np = inet6_sk(sk);
1129	int len;
1130	int val;
1131
1132	if (ip6_mroute_opt(optname))
1133		return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1134
1135	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1136		return -EFAULT;
1137	switch (optname) {
1138	case IPV6_ADDRFORM:
1139		if (sk->sk_protocol != IPPROTO_UDP &&
1140		    sk->sk_protocol != IPPROTO_UDPLITE &&
1141		    sk->sk_protocol != IPPROTO_TCP)
1142			return -ENOPROTOOPT;
1143		if (sk->sk_state != TCP_ESTABLISHED)
1144			return -ENOTCONN;
1145		val = sk->sk_family;
1146		break;
1147	case MCAST_MSFILTER:
1148		if (in_compat_syscall())
1149			return compat_ipv6_get_msfilter(sk, optval, optlen, len);
1150		return ipv6_get_msfilter(sk, optval, optlen, len);
1151	case IPV6_2292PKTOPTIONS:
1152	{
1153		struct msghdr msg;
1154		struct sk_buff *skb;
1155
1156		if (sk->sk_type != SOCK_STREAM)
1157			return -ENOPROTOOPT;
1158
1159		if (optval.is_kernel) {
1160			msg.msg_control_is_user = false;
1161			msg.msg_control = optval.kernel;
1162		} else {
1163			msg.msg_control_is_user = true;
1164			msg.msg_control_user = optval.user;
1165		}
1166		msg.msg_controllen = len;
1167		msg.msg_flags = 0;
1168
1169		sockopt_lock_sock(sk);
1170		skb = np->pktoptions;
1171		if (skb)
1172			ip6_datagram_recv_ctl(sk, &msg, skb);
1173		sockopt_release_sock(sk);
1174		if (!skb) {
1175			if (np->rxopt.bits.rxinfo) {
1176				struct in6_pktinfo src_info;
1177				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1178					np->sticky_pktinfo.ipi6_ifindex;
1179				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1180				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1181			}
1182			if (np->rxopt.bits.rxhlim) {
1183				int hlim = np->mcast_hops;
1184				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1185			}
1186			if (np->rxopt.bits.rxtclass) {
1187				int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1188
1189				put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1190			}
1191			if (np->rxopt.bits.rxoinfo) {
1192				struct in6_pktinfo src_info;
1193				src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1194					np->sticky_pktinfo.ipi6_ifindex;
1195				src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1196								     np->sticky_pktinfo.ipi6_addr;
1197				put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1198			}
1199			if (np->rxopt.bits.rxohlim) {
1200				int hlim = np->mcast_hops;
1201				put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1202			}
1203			if (np->rxopt.bits.rxflow) {
1204				__be32 flowinfo = np->rcv_flowinfo;
1205
1206				put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1207			}
1208		}
1209		len -= msg.msg_controllen;
1210		return copy_to_sockptr(optlen, &len, sizeof(int));
1211	}
1212	case IPV6_MTU:
1213	{
1214		struct dst_entry *dst;
1215
1216		val = 0;
1217		rcu_read_lock();
1218		dst = __sk_dst_get(sk);
1219		if (dst)
1220			val = dst_mtu(dst);
1221		rcu_read_unlock();
1222		if (!val)
1223			return -ENOTCONN;
1224		break;
1225	}
1226
1227	case IPV6_V6ONLY:
1228		val = sk->sk_ipv6only;
1229		break;
1230
1231	case IPV6_RECVPKTINFO:
1232		val = np->rxopt.bits.rxinfo;
1233		break;
1234
1235	case IPV6_2292PKTINFO:
1236		val = np->rxopt.bits.rxoinfo;
1237		break;
1238
1239	case IPV6_RECVHOPLIMIT:
1240		val = np->rxopt.bits.rxhlim;
1241		break;
1242
1243	case IPV6_2292HOPLIMIT:
1244		val = np->rxopt.bits.rxohlim;
1245		break;
1246
1247	case IPV6_RECVRTHDR:
1248		val = np->rxopt.bits.srcrt;
1249		break;
1250
1251	case IPV6_2292RTHDR:
1252		val = np->rxopt.bits.osrcrt;
1253		break;
1254
1255	case IPV6_HOPOPTS:
1256	case IPV6_RTHDRDSTOPTS:
1257	case IPV6_RTHDR:
1258	case IPV6_DSTOPTS:
1259	{
1260		struct ipv6_txoptions *opt;
1261
1262		sockopt_lock_sock(sk);
1263		opt = rcu_dereference_protected(np->opt,
1264						lockdep_sock_is_held(sk));
1265		len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1266		sockopt_release_sock(sk);
1267		/* check if ipv6_getsockopt_sticky() returns err code */
1268		if (len < 0)
1269			return len;
1270		return copy_to_sockptr(optlen, &len, sizeof(int));
1271	}
1272
1273	case IPV6_RECVHOPOPTS:
1274		val = np->rxopt.bits.hopopts;
1275		break;
1276
1277	case IPV6_2292HOPOPTS:
1278		val = np->rxopt.bits.ohopopts;
1279		break;
1280
1281	case IPV6_RECVDSTOPTS:
1282		val = np->rxopt.bits.dstopts;
1283		break;
1284
1285	case IPV6_2292DSTOPTS:
1286		val = np->rxopt.bits.odstopts;
1287		break;
1288
1289	case IPV6_TCLASS:
1290		val = np->tclass;
1291		break;
1292
1293	case IPV6_RECVTCLASS:
1294		val = np->rxopt.bits.rxtclass;
1295		break;
1296
1297	case IPV6_FLOWINFO:
1298		val = np->rxopt.bits.rxflow;
1299		break;
1300
1301	case IPV6_RECVPATHMTU:
1302		val = np->rxopt.bits.rxpmtu;
1303		break;
1304
1305	case IPV6_PATHMTU:
1306	{
1307		struct dst_entry *dst;
1308		struct ip6_mtuinfo mtuinfo;
1309
1310		if (len < sizeof(mtuinfo))
1311			return -EINVAL;
1312
1313		len = sizeof(mtuinfo);
1314		memset(&mtuinfo, 0, sizeof(mtuinfo));
1315
1316		rcu_read_lock();
1317		dst = __sk_dst_get(sk);
1318		if (dst)
1319			mtuinfo.ip6m_mtu = dst_mtu(dst);
1320		rcu_read_unlock();
1321		if (!mtuinfo.ip6m_mtu)
1322			return -ENOTCONN;
1323
1324		if (copy_to_sockptr(optlen, &len, sizeof(int)))
1325			return -EFAULT;
1326		if (copy_to_sockptr(optval, &mtuinfo, len))
1327			return -EFAULT;
1328
1329		return 0;
1330	}
1331
1332	case IPV6_TRANSPARENT:
1333		val = inet_test_bit(TRANSPARENT, sk);
1334		break;
1335
1336	case IPV6_FREEBIND:
1337		val = inet_test_bit(FREEBIND, sk);
1338		break;
1339
1340	case IPV6_RECVORIGDSTADDR:
1341		val = np->rxopt.bits.rxorigdstaddr;
1342		break;
1343
1344	case IPV6_UNICAST_HOPS:
1345	case IPV6_MULTICAST_HOPS:
1346	{
1347		struct dst_entry *dst;
1348
1349		if (optname == IPV6_UNICAST_HOPS)
1350			val = np->hop_limit;
1351		else
1352			val = np->mcast_hops;
1353
1354		if (val < 0) {
1355			rcu_read_lock();
1356			dst = __sk_dst_get(sk);
1357			if (dst)
1358				val = ip6_dst_hoplimit(dst);
1359			rcu_read_unlock();
1360		}
1361
1362		if (val < 0)
1363			val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1364		break;
1365	}
1366
1367	case IPV6_MULTICAST_LOOP:
1368		val = np->mc_loop;
1369		break;
1370
1371	case IPV6_MULTICAST_IF:
1372		val = np->mcast_oif;
1373		break;
1374
1375	case IPV6_MULTICAST_ALL:
1376		val = np->mc_all;
1377		break;
1378
1379	case IPV6_UNICAST_IF:
1380		val = (__force int)htonl((__u32) np->ucast_oif);
1381		break;
1382
1383	case IPV6_MTU_DISCOVER:
1384		val = np->pmtudisc;
1385		break;
1386
1387	case IPV6_RECVERR:
1388		val = np->recverr;
1389		break;
1390
1391	case IPV6_FLOWINFO_SEND:
1392		val = np->sndflow;
1393		break;
1394
1395	case IPV6_FLOWLABEL_MGR:
1396	{
1397		struct in6_flowlabel_req freq;
1398		int flags;
1399
1400		if (len < sizeof(freq))
1401			return -EINVAL;
1402
1403		if (copy_from_sockptr(&freq, optval, sizeof(freq)))
1404			return -EFAULT;
1405
1406		if (freq.flr_action != IPV6_FL_A_GET)
1407			return -EINVAL;
1408
1409		len = sizeof(freq);
1410		flags = freq.flr_flags;
1411
1412		memset(&freq, 0, sizeof(freq));
1413
1414		val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1415		if (val < 0)
1416			return val;
1417
1418		if (copy_to_sockptr(optlen, &len, sizeof(int)))
1419			return -EFAULT;
1420		if (copy_to_sockptr(optval, &freq, len))
1421			return -EFAULT;
1422
1423		return 0;
1424	}
1425
1426	case IPV6_ADDR_PREFERENCES:
1427		val = 0;
1428
1429		if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1430			val |= IPV6_PREFER_SRC_TMP;
1431		else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1432			val |= IPV6_PREFER_SRC_PUBLIC;
1433		else {
1434			/* XXX: should we return system default? */
1435			val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1436		}
1437
1438		if (np->srcprefs & IPV6_PREFER_SRC_COA)
1439			val |= IPV6_PREFER_SRC_COA;
1440		else
1441			val |= IPV6_PREFER_SRC_HOME;
1442		break;
1443
1444	case IPV6_MINHOPCOUNT:
1445		val = np->min_hopcount;
1446		break;
1447
1448	case IPV6_DONTFRAG:
1449		val = np->dontfrag;
1450		break;
1451
1452	case IPV6_AUTOFLOWLABEL:
1453		val = ip6_autoflowlabel(sock_net(sk), np);
1454		break;
1455
1456	case IPV6_RECVFRAGSIZE:
1457		val = np->rxopt.bits.recvfragsize;
1458		break;
1459
1460	case IPV6_ROUTER_ALERT_ISOLATE:
1461		val = np->rtalert_isolate;
1462		break;
1463
1464	case IPV6_RECVERR_RFC4884:
1465		val = np->recverr_rfc4884;
1466		break;
1467
1468	default:
1469		return -ENOPROTOOPT;
1470	}
1471	len = min_t(unsigned int, sizeof(int), len);
1472	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1473		return -EFAULT;
1474	if (copy_to_sockptr(optval, &val, len))
1475		return -EFAULT;
1476	return 0;
1477}
1478
1479int ipv6_getsockopt(struct sock *sk, int level, int optname,
1480		    char __user *optval, int __user *optlen)
1481{
1482	int err;
1483
1484	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1485		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1486
1487	if (level != SOL_IPV6)
1488		return -ENOPROTOOPT;
1489
1490	err = do_ipv6_getsockopt(sk, level, optname,
1491				 USER_SOCKPTR(optval), USER_SOCKPTR(optlen));
1492#ifdef CONFIG_NETFILTER
1493	/* we need to exclude all possible ENOPROTOOPTs except default case */
1494	if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1495		int len;
1496
1497		if (get_user(len, optlen))
1498			return -EFAULT;
1499
1500		err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1501		if (err >= 0)
1502			err = put_user(len, optlen);
1503	}
1504#endif
1505	return err;
1506}
1507EXPORT_SYMBOL(ipv6_getsockopt);
1508