ipv6_sockglue.c revision 6fc0b4a7a73a81e74d0004732df358f4f9975be2
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/config.h>
30#include <linux/errno.h>
31#include <linux/types.h>
32#include <linux/socket.h>
33#include <linux/sockios.h>
34#include <linux/sched.h>
35#include <linux/net.h>
36#include <linux/in6.h>
37#include <linux/netdevice.h>
38#include <linux/if_arp.h>
39#include <linux/init.h>
40#include <linux/sysctl.h>
41#include <linux/netfilter.h>
42
43#include <net/sock.h>
44#include <net/snmp.h>
45#include <net/ipv6.h>
46#include <net/ndisc.h>
47#include <net/protocol.h>
48#include <net/transp_v6.h>
49#include <net/ip6_route.h>
50#include <net/addrconf.h>
51#include <net/inet_common.h>
52#include <net/tcp.h>
53#include <net/udp.h>
54#include <net/xfrm.h>
55
56#include <asm/uaccess.h>
57
58DEFINE_SNMP_STAT(struct ipstats_mib, ipv6_statistics);
59
60static struct packet_type ipv6_packet_type = {
61	.type = __constant_htons(ETH_P_IPV6),
62	.func = ipv6_rcv,
63};
64
65struct ip6_ra_chain *ip6_ra_chain;
66DEFINE_RWLOCK(ip6_ra_lock);
67
68int ip6_ra_control(struct sock *sk, int sel, void (*destructor)(struct sock *))
69{
70	struct ip6_ra_chain *ra, *new_ra, **rap;
71
72	/* RA packet may be delivered ONLY to IPPROTO_RAW socket */
73	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num != IPPROTO_RAW)
74		return -EINVAL;
75
76	new_ra = (sel>=0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
77
78	write_lock_bh(&ip6_ra_lock);
79	for (rap = &ip6_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
80		if (ra->sk == sk) {
81			if (sel>=0) {
82				write_unlock_bh(&ip6_ra_lock);
83				if (new_ra)
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
112extern int ip6_mc_source(int add, int omode, struct sock *sk,
113	struct group_source_req *pgsr);
114extern int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf);
115extern int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
116	struct group_filter __user *optval, int __user *optlen);
117
118
119int ipv6_setsockopt(struct sock *sk, int level, int optname,
120		    char __user *optval, int optlen)
121{
122	struct ipv6_pinfo *np = inet6_sk(sk);
123	int val, valbool;
124	int retv = -ENOPROTOOPT;
125
126	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
127		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
128
129	if(level!=SOL_IPV6)
130		goto out;
131
132	if (optval == NULL)
133		val=0;
134	else if (get_user(val, (int __user *) optval))
135		return -EFAULT;
136
137	valbool = (val!=0);
138
139	lock_sock(sk);
140
141	switch (optname) {
142
143	case IPV6_ADDRFORM:
144		if (val == PF_INET) {
145			struct ipv6_txoptions *opt;
146			struct sk_buff *pktopt;
147
148			if (sk->sk_protocol != IPPROTO_UDP &&
149			    sk->sk_protocol != IPPROTO_TCP)
150				break;
151
152			if (sk->sk_state != TCP_ESTABLISHED) {
153				retv = -ENOTCONN;
154				break;
155			}
156
157			if (ipv6_only_sock(sk) ||
158			    !(ipv6_addr_type(&np->daddr) & IPV6_ADDR_MAPPED)) {
159				retv = -EADDRNOTAVAIL;
160				break;
161			}
162
163			fl6_free_socklist(sk);
164			ipv6_sock_mc_close(sk);
165
166			if (sk->sk_protocol == IPPROTO_TCP) {
167				struct tcp_sock *tp = tcp_sk(sk);
168
169				local_bh_disable();
170				sock_prot_dec_use(sk->sk_prot);
171				sock_prot_inc_use(&tcp_prot);
172				local_bh_enable();
173				sk->sk_prot = &tcp_prot;
174				tp->af_specific = &ipv4_specific;
175				sk->sk_socket->ops = &inet_stream_ops;
176				sk->sk_family = PF_INET;
177				tcp_sync_mss(sk, tp->pmtu_cookie);
178			} else {
179				local_bh_disable();
180				sock_prot_dec_use(sk->sk_prot);
181				sock_prot_inc_use(&udp_prot);
182				local_bh_enable();
183				sk->sk_prot = &udp_prot;
184				sk->sk_socket->ops = &inet_dgram_ops;
185				sk->sk_family = PF_INET;
186			}
187			opt = xchg(&np->opt, NULL);
188			if (opt)
189				sock_kfree_s(sk, opt, opt->tot_len);
190			pktopt = xchg(&np->pktoptions, NULL);
191			if (pktopt)
192				kfree_skb(pktopt);
193
194			sk->sk_destruct = inet_sock_destruct;
195#ifdef INET_REFCNT_DEBUG
196			atomic_dec(&inet6_sock_nr);
197#endif
198			module_put(THIS_MODULE);
199			retv = 0;
200			break;
201		}
202		goto e_inval;
203
204	case IPV6_V6ONLY:
205		if (inet_sk(sk)->num)
206			goto e_inval;
207		np->ipv6only = valbool;
208		retv = 0;
209		break;
210
211	case IPV6_PKTINFO:
212		np->rxopt.bits.rxinfo = valbool;
213		retv = 0;
214		break;
215
216	case IPV6_HOPLIMIT:
217		np->rxopt.bits.rxhlim = valbool;
218		retv = 0;
219		break;
220
221	case IPV6_RTHDR:
222		if (val < 0 || val > 2)
223			goto e_inval;
224		np->rxopt.bits.srcrt = val;
225		retv = 0;
226		break;
227
228	case IPV6_HOPOPTS:
229		np->rxopt.bits.hopopts = valbool;
230		retv = 0;
231		break;
232
233	case IPV6_DSTOPTS:
234		np->rxopt.bits.dstopts = valbool;
235		retv = 0;
236		break;
237
238	case IPV6_FLOWINFO:
239		np->rxopt.bits.rxflow = valbool;
240		retv = 0;
241		break;
242
243	case IPV6_PKTOPTIONS:
244	{
245		struct ipv6_txoptions *opt = NULL;
246		struct msghdr msg;
247		struct flowi fl;
248		int junk;
249
250		fl.fl6_flowlabel = 0;
251		fl.oif = sk->sk_bound_dev_if;
252
253		if (optlen == 0)
254			goto update;
255
256		/* 1K is probably excessive
257		 * 1K is surely not enough, 2K per standard header is 16K.
258		 */
259		retv = -EINVAL;
260		if (optlen > 64*1024)
261			break;
262
263		opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
264		retv = -ENOBUFS;
265		if (opt == NULL)
266			break;
267
268		memset(opt, 0, sizeof(*opt));
269		opt->tot_len = sizeof(*opt) + optlen;
270		retv = -EFAULT;
271		if (copy_from_user(opt+1, optval, optlen))
272			goto done;
273
274		msg.msg_controllen = optlen;
275		msg.msg_control = (void*)(opt+1);
276
277		retv = datagram_send_ctl(&msg, &fl, opt, &junk);
278		if (retv)
279			goto done;
280update:
281		retv = 0;
282		if (sk->sk_type == SOCK_STREAM) {
283			if (opt) {
284				struct tcp_sock *tp = tcp_sk(sk);
285				if (!((1 << sk->sk_state) &
286				      (TCPF_LISTEN | TCPF_CLOSE))
287				    && inet_sk(sk)->daddr != LOOPBACK4_IPV6) {
288					tp->ext_header_len = opt->opt_flen + opt->opt_nflen;
289					tcp_sync_mss(sk, tp->pmtu_cookie);
290				}
291			}
292			opt = xchg(&np->opt, opt);
293			sk_dst_reset(sk);
294		} else {
295			write_lock(&sk->sk_dst_lock);
296			opt = xchg(&np->opt, opt);
297			write_unlock(&sk->sk_dst_lock);
298			sk_dst_reset(sk);
299		}
300
301done:
302		if (opt)
303			sock_kfree_s(sk, opt, opt->tot_len);
304		break;
305	}
306	case IPV6_UNICAST_HOPS:
307		if (val > 255 || val < -1)
308			goto e_inval;
309		np->hop_limit = val;
310		retv = 0;
311		break;
312
313	case IPV6_MULTICAST_HOPS:
314		if (sk->sk_type == SOCK_STREAM)
315			goto e_inval;
316		if (val > 255 || val < -1)
317			goto e_inval;
318		np->mcast_hops = val;
319		retv = 0;
320		break;
321
322	case IPV6_MULTICAST_LOOP:
323		np->mc_loop = valbool;
324		retv = 0;
325		break;
326
327	case IPV6_MULTICAST_IF:
328		if (sk->sk_type == SOCK_STREAM)
329			goto e_inval;
330		if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val)
331			goto e_inval;
332
333		if (__dev_get_by_index(val) == NULL) {
334			retv = -ENODEV;
335			break;
336		}
337		np->mcast_oif = val;
338		retv = 0;
339		break;
340	case IPV6_ADD_MEMBERSHIP:
341	case IPV6_DROP_MEMBERSHIP:
342	{
343		struct ipv6_mreq mreq;
344
345		retv = -EFAULT;
346		if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
347			break;
348
349		if (optname == IPV6_ADD_MEMBERSHIP)
350			retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
351		else
352			retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
353		break;
354	}
355	case IPV6_JOIN_ANYCAST:
356	case IPV6_LEAVE_ANYCAST:
357	{
358		struct ipv6_mreq mreq;
359
360		if (optlen != sizeof(struct ipv6_mreq))
361			goto e_inval;
362
363		retv = -EFAULT;
364		if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
365			break;
366
367		if (optname == IPV6_JOIN_ANYCAST)
368			retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
369		else
370			retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
371		break;
372	}
373	case MCAST_JOIN_GROUP:
374	case MCAST_LEAVE_GROUP:
375	{
376		struct group_req greq;
377		struct sockaddr_in6 *psin6;
378
379		retv = -EFAULT;
380		if (copy_from_user(&greq, optval, sizeof(struct group_req)))
381			break;
382		if (greq.gr_group.ss_family != AF_INET6) {
383			retv = -EADDRNOTAVAIL;
384			break;
385		}
386		psin6 = (struct sockaddr_in6 *)&greq.gr_group;
387		if (optname == MCAST_JOIN_GROUP)
388			retv = ipv6_sock_mc_join(sk, greq.gr_interface,
389				&psin6->sin6_addr);
390		else
391			retv = ipv6_sock_mc_drop(sk, greq.gr_interface,
392				&psin6->sin6_addr);
393		break;
394	}
395	case MCAST_JOIN_SOURCE_GROUP:
396	case MCAST_LEAVE_SOURCE_GROUP:
397	case MCAST_BLOCK_SOURCE:
398	case MCAST_UNBLOCK_SOURCE:
399	{
400		struct group_source_req greqs;
401		int omode, add;
402
403		if (optlen != sizeof(struct group_source_req))
404			goto e_inval;
405		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
406			retv = -EFAULT;
407			break;
408		}
409		if (greqs.gsr_group.ss_family != AF_INET6 ||
410		    greqs.gsr_source.ss_family != AF_INET6) {
411			retv = -EADDRNOTAVAIL;
412			break;
413		}
414		if (optname == MCAST_BLOCK_SOURCE) {
415			omode = MCAST_EXCLUDE;
416			add = 1;
417		} else if (optname == MCAST_UNBLOCK_SOURCE) {
418			omode = MCAST_EXCLUDE;
419			add = 0;
420		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
421			struct sockaddr_in6 *psin6;
422
423			psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
424			retv = ipv6_sock_mc_join(sk, greqs.gsr_interface,
425				&psin6->sin6_addr);
426			/* prior join w/ different source is ok */
427			if (retv && retv != -EADDRINUSE)
428				break;
429			omode = MCAST_INCLUDE;
430			add = 1;
431		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
432			omode = MCAST_INCLUDE;
433			add = 0;
434		}
435		retv = ip6_mc_source(add, omode, sk, &greqs);
436		break;
437	}
438	case MCAST_MSFILTER:
439	{
440		extern int sysctl_optmem_max;
441		extern int sysctl_mld_max_msf;
442		struct group_filter *gsf;
443
444		if (optlen < GROUP_FILTER_SIZE(0))
445			goto e_inval;
446		if (optlen > sysctl_optmem_max) {
447			retv = -ENOBUFS;
448			break;
449		}
450		gsf = (struct group_filter *)kmalloc(optlen,GFP_KERNEL);
451		if (gsf == 0) {
452			retv = -ENOBUFS;
453			break;
454		}
455		retv = -EFAULT;
456		if (copy_from_user(gsf, optval, optlen)) {
457			kfree(gsf);
458			break;
459		}
460		/* numsrc >= (4G-140)/128 overflow in 32 bits */
461		if (gsf->gf_numsrc >= 0x1ffffffU ||
462		    gsf->gf_numsrc > sysctl_mld_max_msf) {
463			kfree(gsf);
464			retv = -ENOBUFS;
465			break;
466		}
467		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
468			kfree(gsf);
469			retv = -EINVAL;
470			break;
471		}
472		retv = ip6_mc_msfilter(sk, gsf);
473		kfree(gsf);
474
475		break;
476	}
477	case IPV6_ROUTER_ALERT:
478		retv = ip6_ra_control(sk, val, NULL);
479		break;
480	case IPV6_MTU_DISCOVER:
481		if (val<0 || val>2)
482			goto e_inval;
483		np->pmtudisc = val;
484		retv = 0;
485		break;
486	case IPV6_MTU:
487		if (val && val < IPV6_MIN_MTU)
488			goto e_inval;
489		np->frag_size = val;
490		retv = 0;
491		break;
492	case IPV6_RECVERR:
493		np->recverr = valbool;
494		if (!val)
495			skb_queue_purge(&sk->sk_error_queue);
496		retv = 0;
497		break;
498	case IPV6_FLOWINFO_SEND:
499		np->sndflow = valbool;
500		retv = 0;
501		break;
502	case IPV6_FLOWLABEL_MGR:
503		retv = ipv6_flowlabel_opt(sk, optval, optlen);
504		break;
505	case IPV6_IPSEC_POLICY:
506	case IPV6_XFRM_POLICY:
507		retv = -EPERM;
508		if (!capable(CAP_NET_ADMIN))
509			break;
510		retv = xfrm_user_policy(sk, optname, optval, optlen);
511		break;
512
513#ifdef CONFIG_NETFILTER
514	default:
515		retv = nf_setsockopt(sk, PF_INET6, optname, optval,
516					    optlen);
517		break;
518#endif
519
520	}
521	release_sock(sk);
522
523out:
524	return retv;
525
526e_inval:
527	release_sock(sk);
528	return -EINVAL;
529}
530
531int ipv6_getsockopt(struct sock *sk, int level, int optname,
532		    char __user *optval, int __user *optlen)
533{
534	struct ipv6_pinfo *np = inet6_sk(sk);
535	int len;
536	int val;
537
538	if (level == SOL_IP && sk->sk_type != SOCK_RAW)
539		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
540	if(level!=SOL_IPV6)
541		return -ENOPROTOOPT;
542	if (get_user(len, optlen))
543		return -EFAULT;
544	switch (optname) {
545	case IPV6_ADDRFORM:
546		if (sk->sk_protocol != IPPROTO_UDP &&
547		    sk->sk_protocol != IPPROTO_TCP)
548			return -EINVAL;
549		if (sk->sk_state != TCP_ESTABLISHED)
550			return -ENOTCONN;
551		val = sk->sk_family;
552		break;
553	case MCAST_MSFILTER:
554	{
555		struct group_filter gsf;
556		int err;
557
558		if (len < GROUP_FILTER_SIZE(0))
559			return -EINVAL;
560		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0)))
561			return -EFAULT;
562		lock_sock(sk);
563		err = ip6_mc_msfget(sk, &gsf,
564			(struct group_filter __user *)optval, optlen);
565		release_sock(sk);
566		return err;
567	}
568
569	case IPV6_PKTOPTIONS:
570	{
571		struct msghdr msg;
572		struct sk_buff *skb;
573
574		if (sk->sk_type != SOCK_STREAM)
575			return -ENOPROTOOPT;
576
577		msg.msg_control = optval;
578		msg.msg_controllen = len;
579		msg.msg_flags = 0;
580
581		lock_sock(sk);
582		skb = np->pktoptions;
583		if (skb)
584			atomic_inc(&skb->users);
585		release_sock(sk);
586
587		if (skb) {
588			int err = datagram_recv_ctl(sk, &msg, skb);
589			kfree_skb(skb);
590			if (err)
591				return err;
592		} else {
593			if (np->rxopt.bits.rxinfo) {
594				struct in6_pktinfo src_info;
595				src_info.ipi6_ifindex = np->mcast_oif;
596				ipv6_addr_copy(&src_info.ipi6_addr, &np->daddr);
597				put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
598			}
599			if (np->rxopt.bits.rxhlim) {
600				int hlim = np->mcast_hops;
601				put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
602			}
603		}
604		len -= msg.msg_controllen;
605		return put_user(len, optlen);
606	}
607	case IPV6_MTU:
608	{
609		struct dst_entry *dst;
610		val = 0;
611		lock_sock(sk);
612		dst = sk_dst_get(sk);
613		if (dst) {
614			val = dst_mtu(dst);
615			dst_release(dst);
616		}
617		release_sock(sk);
618		if (!val)
619			return -ENOTCONN;
620		break;
621	}
622
623	case IPV6_V6ONLY:
624		val = np->ipv6only;
625		break;
626
627	case IPV6_PKTINFO:
628		val = np->rxopt.bits.rxinfo;
629		break;
630
631	case IPV6_HOPLIMIT:
632		val = np->rxopt.bits.rxhlim;
633		break;
634
635	case IPV6_RTHDR:
636		val = np->rxopt.bits.srcrt;
637		break;
638
639	case IPV6_HOPOPTS:
640		val = np->rxopt.bits.hopopts;
641		break;
642
643	case IPV6_DSTOPTS:
644		val = np->rxopt.bits.dstopts;
645		break;
646
647	case IPV6_FLOWINFO:
648		val = np->rxopt.bits.rxflow;
649		break;
650
651	case IPV6_UNICAST_HOPS:
652		val = np->hop_limit;
653		break;
654
655	case IPV6_MULTICAST_HOPS:
656		val = np->mcast_hops;
657		break;
658
659	case IPV6_MULTICAST_LOOP:
660		val = np->mc_loop;
661		break;
662
663	case IPV6_MULTICAST_IF:
664		val = np->mcast_oif;
665		break;
666
667	case IPV6_MTU_DISCOVER:
668		val = np->pmtudisc;
669		break;
670
671	case IPV6_RECVERR:
672		val = np->recverr;
673		break;
674
675	case IPV6_FLOWINFO_SEND:
676		val = np->sndflow;
677		break;
678
679	default:
680#ifdef CONFIG_NETFILTER
681		lock_sock(sk);
682		val = nf_getsockopt(sk, PF_INET6, optname, optval,
683				    &len);
684		release_sock(sk);
685		if (val >= 0)
686			val = put_user(len, optlen);
687		return val;
688#else
689		return -EINVAL;
690#endif
691	}
692	len = min_t(unsigned int, sizeof(int), len);
693	if(put_user(len, optlen))
694		return -EFAULT;
695	if(copy_to_user(optval,&val,len))
696		return -EFAULT;
697	return 0;
698}
699
700void __init ipv6_packet_init(void)
701{
702	dev_add_pack(&ipv6_packet_type);
703}
704
705void ipv6_packet_cleanup(void)
706{
707	dev_remove_pack(&ipv6_packet_type);
708}
709