xref: /openbmc/linux/net/ipv4/ip_sockglue.c (revision 22246614)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		The IP to API glue.
7  *
8  * Version:	$Id: ip_sockglue.c,v 1.62 2002/02/01 22:01:04 davem Exp $
9  *
10  * Authors:	see ip.c
11  *
12  * Fixes:
13  *		Many		:	Split from ip.c , see ip.c for history.
14  *		Martin Mares	:	TOS setting fixed.
15  *		Alan Cox	:	Fixed a couple of oopses in Martin's
16  *					TOS tweaks.
17  *		Mike McLagan	:	Routing by source
18  */
19 
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/mm.h>
23 #include <linux/skbuff.h>
24 #include <linux/ip.h>
25 #include <linux/icmp.h>
26 #include <linux/inetdevice.h>
27 #include <linux/netdevice.h>
28 #include <net/sock.h>
29 #include <net/ip.h>
30 #include <net/icmp.h>
31 #include <net/tcp_states.h>
32 #include <linux/udp.h>
33 #include <linux/igmp.h>
34 #include <linux/netfilter.h>
35 #include <linux/route.h>
36 #include <linux/mroute.h>
37 #include <net/route.h>
38 #include <net/xfrm.h>
39 #include <net/compat.h>
40 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
41 #include <net/transp_v6.h>
42 #endif
43 
44 #include <linux/errqueue.h>
45 #include <asm/uaccess.h>
46 
47 #define IP_CMSG_PKTINFO		1
48 #define IP_CMSG_TTL		2
49 #define IP_CMSG_TOS		4
50 #define IP_CMSG_RECVOPTS	8
51 #define IP_CMSG_RETOPTS		16
52 #define IP_CMSG_PASSSEC		32
53 
54 /*
55  *	SOL_IP control messages.
56  */
57 
58 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
59 {
60 	struct in_pktinfo info;
61 	struct rtable *rt = skb->rtable;
62 
63 	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
64 	if (rt) {
65 		info.ipi_ifindex = rt->rt_iif;
66 		info.ipi_spec_dst.s_addr = rt->rt_spec_dst;
67 	} else {
68 		info.ipi_ifindex = 0;
69 		info.ipi_spec_dst.s_addr = 0;
70 	}
71 
72 	put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
73 }
74 
75 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
76 {
77 	int ttl = ip_hdr(skb)->ttl;
78 	put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
79 }
80 
81 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
82 {
83 	put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
84 }
85 
86 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
87 {
88 	if (IPCB(skb)->opt.optlen == 0)
89 		return;
90 
91 	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
92 		 ip_hdr(skb) + 1);
93 }
94 
95 
96 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
97 {
98 	unsigned char optbuf[sizeof(struct ip_options) + 40];
99 	struct ip_options * opt = (struct ip_options*)optbuf;
100 
101 	if (IPCB(skb)->opt.optlen == 0)
102 		return;
103 
104 	if (ip_options_echo(opt, skb)) {
105 		msg->msg_flags |= MSG_CTRUNC;
106 		return;
107 	}
108 	ip_options_undo(opt);
109 
110 	put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
111 }
112 
113 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
114 {
115 	char *secdata;
116 	u32 seclen, secid;
117 	int err;
118 
119 	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
120 	if (err)
121 		return;
122 
123 	err = security_secid_to_secctx(secid, &secdata, &seclen);
124 	if (err)
125 		return;
126 
127 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
128 	security_release_secctx(secdata, seclen);
129 }
130 
131 
132 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
133 {
134 	struct inet_sock *inet = inet_sk(skb->sk);
135 	unsigned flags = inet->cmsg_flags;
136 
137 	/* Ordered by supposed usage frequency */
138 	if (flags & 1)
139 		ip_cmsg_recv_pktinfo(msg, skb);
140 	if ((flags>>=1) == 0)
141 		return;
142 
143 	if (flags & 1)
144 		ip_cmsg_recv_ttl(msg, skb);
145 	if ((flags>>=1) == 0)
146 		return;
147 
148 	if (flags & 1)
149 		ip_cmsg_recv_tos(msg, skb);
150 	if ((flags>>=1) == 0)
151 		return;
152 
153 	if (flags & 1)
154 		ip_cmsg_recv_opts(msg, skb);
155 	if ((flags>>=1) == 0)
156 		return;
157 
158 	if (flags & 1)
159 		ip_cmsg_recv_retopts(msg, skb);
160 	if ((flags>>=1) == 0)
161 		return;
162 
163 	if (flags & 1)
164 		ip_cmsg_recv_security(msg, skb);
165 }
166 
167 int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
168 {
169 	int err;
170 	struct cmsghdr *cmsg;
171 
172 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
173 		if (!CMSG_OK(msg, cmsg))
174 			return -EINVAL;
175 		if (cmsg->cmsg_level != SOL_IP)
176 			continue;
177 		switch (cmsg->cmsg_type) {
178 		case IP_RETOPTS:
179 			err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
180 			err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg), err < 40 ? err : 40);
181 			if (err)
182 				return err;
183 			break;
184 		case IP_PKTINFO:
185 		{
186 			struct in_pktinfo *info;
187 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
188 				return -EINVAL;
189 			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
190 			ipc->oif = info->ipi_ifindex;
191 			ipc->addr = info->ipi_spec_dst.s_addr;
192 			break;
193 		}
194 		default:
195 			return -EINVAL;
196 		}
197 	}
198 	return 0;
199 }
200 
201 
202 /* Special input handler for packets caught by router alert option.
203    They are selected only by protocol field, and then processed likely
204    local ones; but only if someone wants them! Otherwise, router
205    not running rsvpd will kill RSVP.
206 
207    It is user level problem, what it will make with them.
208    I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
209    but receiver should be enough clever f.e. to forward mtrace requests,
210    sent to multicast group to reach destination designated router.
211  */
212 struct ip_ra_chain *ip_ra_chain;
213 DEFINE_RWLOCK(ip_ra_lock);
214 
215 int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *))
216 {
217 	struct ip_ra_chain *ra, *new_ra, **rap;
218 
219 	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num == IPPROTO_RAW)
220 		return -EINVAL;
221 
222 	new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
223 
224 	write_lock_bh(&ip_ra_lock);
225 	for (rap = &ip_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
226 		if (ra->sk == sk) {
227 			if (on) {
228 				write_unlock_bh(&ip_ra_lock);
229 				kfree(new_ra);
230 				return -EADDRINUSE;
231 			}
232 			*rap = ra->next;
233 			write_unlock_bh(&ip_ra_lock);
234 
235 			if (ra->destructor)
236 				ra->destructor(sk);
237 			sock_put(sk);
238 			kfree(ra);
239 			return 0;
240 		}
241 	}
242 	if (new_ra == NULL) {
243 		write_unlock_bh(&ip_ra_lock);
244 		return -ENOBUFS;
245 	}
246 	new_ra->sk = sk;
247 	new_ra->destructor = destructor;
248 
249 	new_ra->next = ra;
250 	*rap = new_ra;
251 	sock_hold(sk);
252 	write_unlock_bh(&ip_ra_lock);
253 
254 	return 0;
255 }
256 
257 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
258 		   __be16 port, u32 info, u8 *payload)
259 {
260 	struct inet_sock *inet = inet_sk(sk);
261 	struct sock_exterr_skb *serr;
262 
263 	if (!inet->recverr)
264 		return;
265 
266 	skb = skb_clone(skb, GFP_ATOMIC);
267 	if (!skb)
268 		return;
269 
270 	serr = SKB_EXT_ERR(skb);
271 	serr->ee.ee_errno = err;
272 	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
273 	serr->ee.ee_type = icmp_hdr(skb)->type;
274 	serr->ee.ee_code = icmp_hdr(skb)->code;
275 	serr->ee.ee_pad = 0;
276 	serr->ee.ee_info = info;
277 	serr->ee.ee_data = 0;
278 	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
279 				   skb_network_header(skb);
280 	serr->port = port;
281 
282 	if (skb_pull(skb, payload - skb->data) != NULL) {
283 		skb_reset_transport_header(skb);
284 		if (sock_queue_err_skb(sk, skb) == 0)
285 			return;
286 	}
287 	kfree_skb(skb);
288 }
289 
290 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
291 {
292 	struct inet_sock *inet = inet_sk(sk);
293 	struct sock_exterr_skb *serr;
294 	struct iphdr *iph;
295 	struct sk_buff *skb;
296 
297 	if (!inet->recverr)
298 		return;
299 
300 	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
301 	if (!skb)
302 		return;
303 
304 	skb_put(skb, sizeof(struct iphdr));
305 	skb_reset_network_header(skb);
306 	iph = ip_hdr(skb);
307 	iph->daddr = daddr;
308 
309 	serr = SKB_EXT_ERR(skb);
310 	serr->ee.ee_errno = err;
311 	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
312 	serr->ee.ee_type = 0;
313 	serr->ee.ee_code = 0;
314 	serr->ee.ee_pad = 0;
315 	serr->ee.ee_info = info;
316 	serr->ee.ee_data = 0;
317 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
318 	serr->port = port;
319 
320 	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
321 	skb_reset_transport_header(skb);
322 
323 	if (sock_queue_err_skb(sk, skb))
324 		kfree_skb(skb);
325 }
326 
327 /*
328  *	Handle MSG_ERRQUEUE
329  */
330 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
331 {
332 	struct sock_exterr_skb *serr;
333 	struct sk_buff *skb, *skb2;
334 	struct sockaddr_in *sin;
335 	struct {
336 		struct sock_extended_err ee;
337 		struct sockaddr_in	 offender;
338 	} errhdr;
339 	int err;
340 	int copied;
341 
342 	err = -EAGAIN;
343 	skb = skb_dequeue(&sk->sk_error_queue);
344 	if (skb == NULL)
345 		goto out;
346 
347 	copied = skb->len;
348 	if (copied > len) {
349 		msg->msg_flags |= MSG_TRUNC;
350 		copied = len;
351 	}
352 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
353 	if (err)
354 		goto out_free_skb;
355 
356 	sock_recv_timestamp(msg, sk, skb);
357 
358 	serr = SKB_EXT_ERR(skb);
359 
360 	sin = (struct sockaddr_in *)msg->msg_name;
361 	if (sin) {
362 		sin->sin_family = AF_INET;
363 		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
364 						   serr->addr_offset);
365 		sin->sin_port = serr->port;
366 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
367 	}
368 
369 	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
370 	sin = &errhdr.offender;
371 	sin->sin_family = AF_UNSPEC;
372 	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
373 		struct inet_sock *inet = inet_sk(sk);
374 
375 		sin->sin_family = AF_INET;
376 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
377 		sin->sin_port = 0;
378 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
379 		if (inet->cmsg_flags)
380 			ip_cmsg_recv(msg, skb);
381 	}
382 
383 	put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
384 
385 	/* Now we could try to dump offended packet options */
386 
387 	msg->msg_flags |= MSG_ERRQUEUE;
388 	err = copied;
389 
390 	/* Reset and regenerate socket error */
391 	spin_lock_bh(&sk->sk_error_queue.lock);
392 	sk->sk_err = 0;
393 	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
394 		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
395 		spin_unlock_bh(&sk->sk_error_queue.lock);
396 		sk->sk_error_report(sk);
397 	} else
398 		spin_unlock_bh(&sk->sk_error_queue.lock);
399 
400 out_free_skb:
401 	kfree_skb(skb);
402 out:
403 	return err;
404 }
405 
406 
407 /*
408  *	Socket option code for IP. This is the end of the line after any TCP,UDP etc options on
409  *	an IP socket.
410  */
411 
412 static int do_ip_setsockopt(struct sock *sk, int level,
413 			    int optname, char __user *optval, int optlen)
414 {
415 	struct inet_sock *inet = inet_sk(sk);
416 	int val=0,err;
417 
418 	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
419 			     (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
420 			     (1<<IP_RETOPTS) | (1<<IP_TOS) |
421 			     (1<<IP_TTL) | (1<<IP_HDRINCL) |
422 			     (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
423 			     (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
424 			     (1<<IP_PASSSEC))) ||
425 	    optname == IP_MULTICAST_TTL ||
426 	    optname == IP_MULTICAST_LOOP) {
427 		if (optlen >= sizeof(int)) {
428 			if (get_user(val, (int __user *) optval))
429 				return -EFAULT;
430 		} else if (optlen >= sizeof(char)) {
431 			unsigned char ucval;
432 
433 			if (get_user(ucval, (unsigned char __user *) optval))
434 				return -EFAULT;
435 			val = (int) ucval;
436 		}
437 	}
438 
439 	/* If optlen==0, it is equivalent to val == 0 */
440 
441 	if (ip_mroute_opt(optname))
442 		return ip_mroute_setsockopt(sk,optname,optval,optlen);
443 
444 	err = 0;
445 	lock_sock(sk);
446 
447 	switch (optname) {
448 	case IP_OPTIONS:
449 	{
450 		struct ip_options * opt = NULL;
451 		if (optlen > 40 || optlen < 0)
452 			goto e_inval;
453 		err = ip_options_get_from_user(sock_net(sk), &opt,
454 					       optval, optlen);
455 		if (err)
456 			break;
457 		if (inet->is_icsk) {
458 			struct inet_connection_sock *icsk = inet_csk(sk);
459 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
460 			if (sk->sk_family == PF_INET ||
461 			    (!((1 << sk->sk_state) &
462 			       (TCPF_LISTEN | TCPF_CLOSE)) &&
463 			     inet->daddr != LOOPBACK4_IPV6)) {
464 #endif
465 				if (inet->opt)
466 					icsk->icsk_ext_hdr_len -= inet->opt->optlen;
467 				if (opt)
468 					icsk->icsk_ext_hdr_len += opt->optlen;
469 				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
470 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
471 			}
472 #endif
473 		}
474 		opt = xchg(&inet->opt, opt);
475 		kfree(opt);
476 		break;
477 	}
478 	case IP_PKTINFO:
479 		if (val)
480 			inet->cmsg_flags |= IP_CMSG_PKTINFO;
481 		else
482 			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
483 		break;
484 	case IP_RECVTTL:
485 		if (val)
486 			inet->cmsg_flags |=  IP_CMSG_TTL;
487 		else
488 			inet->cmsg_flags &= ~IP_CMSG_TTL;
489 		break;
490 	case IP_RECVTOS:
491 		if (val)
492 			inet->cmsg_flags |=  IP_CMSG_TOS;
493 		else
494 			inet->cmsg_flags &= ~IP_CMSG_TOS;
495 		break;
496 	case IP_RECVOPTS:
497 		if (val)
498 			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
499 		else
500 			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
501 		break;
502 	case IP_RETOPTS:
503 		if (val)
504 			inet->cmsg_flags |= IP_CMSG_RETOPTS;
505 		else
506 			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
507 		break;
508 	case IP_PASSSEC:
509 		if (val)
510 			inet->cmsg_flags |= IP_CMSG_PASSSEC;
511 		else
512 			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
513 		break;
514 	case IP_TOS:	/* This sets both TOS and Precedence */
515 		if (sk->sk_type == SOCK_STREAM) {
516 			val &= ~3;
517 			val |= inet->tos & 3;
518 		}
519 		if (inet->tos != val) {
520 			inet->tos = val;
521 			sk->sk_priority = rt_tos2priority(val);
522 			sk_dst_reset(sk);
523 		}
524 		break;
525 	case IP_TTL:
526 		if (optlen<1)
527 			goto e_inval;
528 		if (val != -1 && (val < 1 || val>255))
529 			goto e_inval;
530 		inet->uc_ttl = val;
531 		break;
532 	case IP_HDRINCL:
533 		if (sk->sk_type != SOCK_RAW) {
534 			err = -ENOPROTOOPT;
535 			break;
536 		}
537 		inet->hdrincl = val ? 1 : 0;
538 		break;
539 	case IP_MTU_DISCOVER:
540 		if (val<0 || val>3)
541 			goto e_inval;
542 		inet->pmtudisc = val;
543 		break;
544 	case IP_RECVERR:
545 		inet->recverr = !!val;
546 		if (!val)
547 			skb_queue_purge(&sk->sk_error_queue);
548 		break;
549 	case IP_MULTICAST_TTL:
550 		if (sk->sk_type == SOCK_STREAM)
551 			goto e_inval;
552 		if (optlen<1)
553 			goto e_inval;
554 		if (val==-1)
555 			val = 1;
556 		if (val < 0 || val > 255)
557 			goto e_inval;
558 		inet->mc_ttl = val;
559 		break;
560 	case IP_MULTICAST_LOOP:
561 		if (optlen<1)
562 			goto e_inval;
563 		inet->mc_loop = !!val;
564 		break;
565 	case IP_MULTICAST_IF:
566 	{
567 		struct ip_mreqn mreq;
568 		struct net_device *dev = NULL;
569 
570 		if (sk->sk_type == SOCK_STREAM)
571 			goto e_inval;
572 		/*
573 		 *	Check the arguments are allowable
574 		 */
575 
576 		err = -EFAULT;
577 		if (optlen >= sizeof(struct ip_mreqn)) {
578 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
579 				break;
580 		} else {
581 			memset(&mreq, 0, sizeof(mreq));
582 			if (optlen >= sizeof(struct in_addr) &&
583 			    copy_from_user(&mreq.imr_address,optval,sizeof(struct in_addr)))
584 				break;
585 		}
586 
587 		if (!mreq.imr_ifindex) {
588 			if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
589 				inet->mc_index = 0;
590 				inet->mc_addr  = 0;
591 				err = 0;
592 				break;
593 			}
594 			dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
595 			if (dev) {
596 				mreq.imr_ifindex = dev->ifindex;
597 				dev_put(dev);
598 			}
599 		} else
600 			dev = __dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
601 
602 
603 		err = -EADDRNOTAVAIL;
604 		if (!dev)
605 			break;
606 
607 		err = -EINVAL;
608 		if (sk->sk_bound_dev_if &&
609 		    mreq.imr_ifindex != sk->sk_bound_dev_if)
610 			break;
611 
612 		inet->mc_index = mreq.imr_ifindex;
613 		inet->mc_addr  = mreq.imr_address.s_addr;
614 		err = 0;
615 		break;
616 	}
617 
618 	case IP_ADD_MEMBERSHIP:
619 	case IP_DROP_MEMBERSHIP:
620 	{
621 		struct ip_mreqn mreq;
622 
623 		err = -EPROTO;
624 		if (inet_sk(sk)->is_icsk)
625 			break;
626 
627 		if (optlen < sizeof(struct ip_mreq))
628 			goto e_inval;
629 		err = -EFAULT;
630 		if (optlen >= sizeof(struct ip_mreqn)) {
631 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
632 				break;
633 		} else {
634 			memset(&mreq, 0, sizeof(mreq));
635 			if (copy_from_user(&mreq,optval,sizeof(struct ip_mreq)))
636 				break;
637 		}
638 
639 		if (optname == IP_ADD_MEMBERSHIP)
640 			err = ip_mc_join_group(sk, &mreq);
641 		else
642 			err = ip_mc_leave_group(sk, &mreq);
643 		break;
644 	}
645 	case IP_MSFILTER:
646 	{
647 		extern int sysctl_igmp_max_msf;
648 		struct ip_msfilter *msf;
649 
650 		if (optlen < IP_MSFILTER_SIZE(0))
651 			goto e_inval;
652 		if (optlen > sysctl_optmem_max) {
653 			err = -ENOBUFS;
654 			break;
655 		}
656 		msf = kmalloc(optlen, GFP_KERNEL);
657 		if (!msf) {
658 			err = -ENOBUFS;
659 			break;
660 		}
661 		err = -EFAULT;
662 		if (copy_from_user(msf, optval, optlen)) {
663 			kfree(msf);
664 			break;
665 		}
666 		/* numsrc >= (1G-4) overflow in 32 bits */
667 		if (msf->imsf_numsrc >= 0x3ffffffcU ||
668 		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
669 			kfree(msf);
670 			err = -ENOBUFS;
671 			break;
672 		}
673 		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
674 			kfree(msf);
675 			err = -EINVAL;
676 			break;
677 		}
678 		err = ip_mc_msfilter(sk, msf, 0);
679 		kfree(msf);
680 		break;
681 	}
682 	case IP_BLOCK_SOURCE:
683 	case IP_UNBLOCK_SOURCE:
684 	case IP_ADD_SOURCE_MEMBERSHIP:
685 	case IP_DROP_SOURCE_MEMBERSHIP:
686 	{
687 		struct ip_mreq_source mreqs;
688 		int omode, add;
689 
690 		if (optlen != sizeof(struct ip_mreq_source))
691 			goto e_inval;
692 		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
693 			err = -EFAULT;
694 			break;
695 		}
696 		if (optname == IP_BLOCK_SOURCE) {
697 			omode = MCAST_EXCLUDE;
698 			add = 1;
699 		} else if (optname == IP_UNBLOCK_SOURCE) {
700 			omode = MCAST_EXCLUDE;
701 			add = 0;
702 		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
703 			struct ip_mreqn mreq;
704 
705 			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
706 			mreq.imr_address.s_addr = mreqs.imr_interface;
707 			mreq.imr_ifindex = 0;
708 			err = ip_mc_join_group(sk, &mreq);
709 			if (err && err != -EADDRINUSE)
710 				break;
711 			omode = MCAST_INCLUDE;
712 			add = 1;
713 		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
714 			omode = MCAST_INCLUDE;
715 			add = 0;
716 		}
717 		err = ip_mc_source(add, omode, sk, &mreqs, 0);
718 		break;
719 	}
720 	case MCAST_JOIN_GROUP:
721 	case MCAST_LEAVE_GROUP:
722 	{
723 		struct group_req greq;
724 		struct sockaddr_in *psin;
725 		struct ip_mreqn mreq;
726 
727 		if (optlen < sizeof(struct group_req))
728 			goto e_inval;
729 		err = -EFAULT;
730 		if (copy_from_user(&greq, optval, sizeof(greq)))
731 			break;
732 		psin = (struct sockaddr_in *)&greq.gr_group;
733 		if (psin->sin_family != AF_INET)
734 			goto e_inval;
735 		memset(&mreq, 0, sizeof(mreq));
736 		mreq.imr_multiaddr = psin->sin_addr;
737 		mreq.imr_ifindex = greq.gr_interface;
738 
739 		if (optname == MCAST_JOIN_GROUP)
740 			err = ip_mc_join_group(sk, &mreq);
741 		else
742 			err = ip_mc_leave_group(sk, &mreq);
743 		break;
744 	}
745 	case MCAST_JOIN_SOURCE_GROUP:
746 	case MCAST_LEAVE_SOURCE_GROUP:
747 	case MCAST_BLOCK_SOURCE:
748 	case MCAST_UNBLOCK_SOURCE:
749 	{
750 		struct group_source_req greqs;
751 		struct ip_mreq_source mreqs;
752 		struct sockaddr_in *psin;
753 		int omode, add;
754 
755 		if (optlen != sizeof(struct group_source_req))
756 			goto e_inval;
757 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
758 			err = -EFAULT;
759 			break;
760 		}
761 		if (greqs.gsr_group.ss_family != AF_INET ||
762 		    greqs.gsr_source.ss_family != AF_INET) {
763 			err = -EADDRNOTAVAIL;
764 			break;
765 		}
766 		psin = (struct sockaddr_in *)&greqs.gsr_group;
767 		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
768 		psin = (struct sockaddr_in *)&greqs.gsr_source;
769 		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
770 		mreqs.imr_interface = 0; /* use index for mc_source */
771 
772 		if (optname == MCAST_BLOCK_SOURCE) {
773 			omode = MCAST_EXCLUDE;
774 			add = 1;
775 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
776 			omode = MCAST_EXCLUDE;
777 			add = 0;
778 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
779 			struct ip_mreqn mreq;
780 
781 			psin = (struct sockaddr_in *)&greqs.gsr_group;
782 			mreq.imr_multiaddr = psin->sin_addr;
783 			mreq.imr_address.s_addr = 0;
784 			mreq.imr_ifindex = greqs.gsr_interface;
785 			err = ip_mc_join_group(sk, &mreq);
786 			if (err && err != -EADDRINUSE)
787 				break;
788 			greqs.gsr_interface = mreq.imr_ifindex;
789 			omode = MCAST_INCLUDE;
790 			add = 1;
791 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
792 			omode = MCAST_INCLUDE;
793 			add = 0;
794 		}
795 		err = ip_mc_source(add, omode, sk, &mreqs,
796 				   greqs.gsr_interface);
797 		break;
798 	}
799 	case MCAST_MSFILTER:
800 	{
801 		extern int sysctl_igmp_max_msf;
802 		struct sockaddr_in *psin;
803 		struct ip_msfilter *msf = NULL;
804 		struct group_filter *gsf = NULL;
805 		int msize, i, ifindex;
806 
807 		if (optlen < GROUP_FILTER_SIZE(0))
808 			goto e_inval;
809 		if (optlen > sysctl_optmem_max) {
810 			err = -ENOBUFS;
811 			break;
812 		}
813 		gsf = kmalloc(optlen,GFP_KERNEL);
814 		if (!gsf) {
815 			err = -ENOBUFS;
816 			break;
817 		}
818 		err = -EFAULT;
819 		if (copy_from_user(gsf, optval, optlen)) {
820 			goto mc_msf_out;
821 		}
822 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
823 		if (gsf->gf_numsrc >= 0x1ffffff ||
824 		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
825 			err = -ENOBUFS;
826 			goto mc_msf_out;
827 		}
828 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
829 			err = -EINVAL;
830 			goto mc_msf_out;
831 		}
832 		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
833 		msf = kmalloc(msize,GFP_KERNEL);
834 		if (!msf) {
835 			err = -ENOBUFS;
836 			goto mc_msf_out;
837 		}
838 		ifindex = gsf->gf_interface;
839 		psin = (struct sockaddr_in *)&gsf->gf_group;
840 		if (psin->sin_family != AF_INET) {
841 			err = -EADDRNOTAVAIL;
842 			goto mc_msf_out;
843 		}
844 		msf->imsf_multiaddr = psin->sin_addr.s_addr;
845 		msf->imsf_interface = 0;
846 		msf->imsf_fmode = gsf->gf_fmode;
847 		msf->imsf_numsrc = gsf->gf_numsrc;
848 		err = -EADDRNOTAVAIL;
849 		for (i=0; i<gsf->gf_numsrc; ++i) {
850 			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
851 
852 			if (psin->sin_family != AF_INET)
853 				goto mc_msf_out;
854 			msf->imsf_slist[i] = psin->sin_addr.s_addr;
855 		}
856 		kfree(gsf);
857 		gsf = NULL;
858 
859 		err = ip_mc_msfilter(sk, msf, ifindex);
860 	mc_msf_out:
861 		kfree(msf);
862 		kfree(gsf);
863 		break;
864 	}
865 	case IP_ROUTER_ALERT:
866 		err = ip_ra_control(sk, val ? 1 : 0, NULL);
867 		break;
868 
869 	case IP_FREEBIND:
870 		if (optlen<1)
871 			goto e_inval;
872 		inet->freebind = !!val;
873 		break;
874 
875 	case IP_IPSEC_POLICY:
876 	case IP_XFRM_POLICY:
877 		err = -EPERM;
878 		if (!capable(CAP_NET_ADMIN))
879 			break;
880 		err = xfrm_user_policy(sk, optname, optval, optlen);
881 		break;
882 
883 	default:
884 		err = -ENOPROTOOPT;
885 		break;
886 	}
887 	release_sock(sk);
888 	return err;
889 
890 e_inval:
891 	release_sock(sk);
892 	return -EINVAL;
893 }
894 
895 int ip_setsockopt(struct sock *sk, int level,
896 		int optname, char __user *optval, int optlen)
897 {
898 	int err;
899 
900 	if (level != SOL_IP)
901 		return -ENOPROTOOPT;
902 
903 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
904 #ifdef CONFIG_NETFILTER
905 	/* we need to exclude all possible ENOPROTOOPTs except default case */
906 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
907 			optname != IP_IPSEC_POLICY &&
908 			optname != IP_XFRM_POLICY &&
909 			!ip_mroute_opt(optname)) {
910 		lock_sock(sk);
911 		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
912 		release_sock(sk);
913 	}
914 #endif
915 	return err;
916 }
917 
918 #ifdef CONFIG_COMPAT
919 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
920 			 char __user *optval, int optlen)
921 {
922 	int err;
923 
924 	if (level != SOL_IP)
925 		return -ENOPROTOOPT;
926 
927 	if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
928 		return compat_mc_setsockopt(sk, level, optname, optval, optlen,
929 			ip_setsockopt);
930 
931 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
932 #ifdef CONFIG_NETFILTER
933 	/* we need to exclude all possible ENOPROTOOPTs except default case */
934 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
935 			optname != IP_IPSEC_POLICY &&
936 			optname != IP_XFRM_POLICY &&
937 			!ip_mroute_opt(optname)) {
938 		lock_sock(sk);
939 		err = compat_nf_setsockopt(sk, PF_INET, optname,
940 					   optval, optlen);
941 		release_sock(sk);
942 	}
943 #endif
944 	return err;
945 }
946 
947 EXPORT_SYMBOL(compat_ip_setsockopt);
948 #endif
949 
950 /*
951  *	Get the options. Note for future reference. The GET of IP options gets the
952  *	_received_ ones. The set sets the _sent_ ones.
953  */
954 
955 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
956 			    char __user *optval, int __user *optlen)
957 {
958 	struct inet_sock *inet = inet_sk(sk);
959 	int val;
960 	int len;
961 
962 	if (level != SOL_IP)
963 		return -EOPNOTSUPP;
964 
965 	if (ip_mroute_opt(optname))
966 		return ip_mroute_getsockopt(sk,optname,optval,optlen);
967 
968 	if (get_user(len,optlen))
969 		return -EFAULT;
970 	if (len < 0)
971 		return -EINVAL;
972 
973 	lock_sock(sk);
974 
975 	switch (optname) {
976 	case IP_OPTIONS:
977 	{
978 		unsigned char optbuf[sizeof(struct ip_options)+40];
979 		struct ip_options * opt = (struct ip_options*)optbuf;
980 		opt->optlen = 0;
981 		if (inet->opt)
982 			memcpy(optbuf, inet->opt,
983 			       sizeof(struct ip_options)+
984 			       inet->opt->optlen);
985 		release_sock(sk);
986 
987 		if (opt->optlen == 0)
988 			return put_user(0, optlen);
989 
990 		ip_options_undo(opt);
991 
992 		len = min_t(unsigned int, len, opt->optlen);
993 		if (put_user(len, optlen))
994 			return -EFAULT;
995 		if (copy_to_user(optval, opt->__data, len))
996 			return -EFAULT;
997 		return 0;
998 	}
999 	case IP_PKTINFO:
1000 		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1001 		break;
1002 	case IP_RECVTTL:
1003 		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1004 		break;
1005 	case IP_RECVTOS:
1006 		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1007 		break;
1008 	case IP_RECVOPTS:
1009 		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1010 		break;
1011 	case IP_RETOPTS:
1012 		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1013 		break;
1014 	case IP_PASSSEC:
1015 		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1016 		break;
1017 	case IP_TOS:
1018 		val = inet->tos;
1019 		break;
1020 	case IP_TTL:
1021 		val = (inet->uc_ttl == -1 ?
1022 		       sysctl_ip_default_ttl :
1023 		       inet->uc_ttl);
1024 		break;
1025 	case IP_HDRINCL:
1026 		val = inet->hdrincl;
1027 		break;
1028 	case IP_MTU_DISCOVER:
1029 		val = inet->pmtudisc;
1030 		break;
1031 	case IP_MTU:
1032 	{
1033 		struct dst_entry *dst;
1034 		val = 0;
1035 		dst = sk_dst_get(sk);
1036 		if (dst) {
1037 			val = dst_mtu(dst);
1038 			dst_release(dst);
1039 		}
1040 		if (!val) {
1041 			release_sock(sk);
1042 			return -ENOTCONN;
1043 		}
1044 		break;
1045 	}
1046 	case IP_RECVERR:
1047 		val = inet->recverr;
1048 		break;
1049 	case IP_MULTICAST_TTL:
1050 		val = inet->mc_ttl;
1051 		break;
1052 	case IP_MULTICAST_LOOP:
1053 		val = inet->mc_loop;
1054 		break;
1055 	case IP_MULTICAST_IF:
1056 	{
1057 		struct in_addr addr;
1058 		len = min_t(unsigned int, len, sizeof(struct in_addr));
1059 		addr.s_addr = inet->mc_addr;
1060 		release_sock(sk);
1061 
1062 		if (put_user(len, optlen))
1063 			return -EFAULT;
1064 		if (copy_to_user(optval, &addr, len))
1065 			return -EFAULT;
1066 		return 0;
1067 	}
1068 	case IP_MSFILTER:
1069 	{
1070 		struct ip_msfilter msf;
1071 		int err;
1072 
1073 		if (len < IP_MSFILTER_SIZE(0)) {
1074 			release_sock(sk);
1075 			return -EINVAL;
1076 		}
1077 		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1078 			release_sock(sk);
1079 			return -EFAULT;
1080 		}
1081 		err = ip_mc_msfget(sk, &msf,
1082 				   (struct ip_msfilter __user *)optval, optlen);
1083 		release_sock(sk);
1084 		return err;
1085 	}
1086 	case MCAST_MSFILTER:
1087 	{
1088 		struct group_filter gsf;
1089 		int err;
1090 
1091 		if (len < GROUP_FILTER_SIZE(0)) {
1092 			release_sock(sk);
1093 			return -EINVAL;
1094 		}
1095 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1096 			release_sock(sk);
1097 			return -EFAULT;
1098 		}
1099 		err = ip_mc_gsfget(sk, &gsf,
1100 				   (struct group_filter __user *)optval, optlen);
1101 		release_sock(sk);
1102 		return err;
1103 	}
1104 	case IP_PKTOPTIONS:
1105 	{
1106 		struct msghdr msg;
1107 
1108 		release_sock(sk);
1109 
1110 		if (sk->sk_type != SOCK_STREAM)
1111 			return -ENOPROTOOPT;
1112 
1113 		msg.msg_control = optval;
1114 		msg.msg_controllen = len;
1115 		msg.msg_flags = 0;
1116 
1117 		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1118 			struct in_pktinfo info;
1119 
1120 			info.ipi_addr.s_addr = inet->rcv_saddr;
1121 			info.ipi_spec_dst.s_addr = inet->rcv_saddr;
1122 			info.ipi_ifindex = inet->mc_index;
1123 			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1124 		}
1125 		if (inet->cmsg_flags & IP_CMSG_TTL) {
1126 			int hlim = inet->mc_ttl;
1127 			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1128 		}
1129 		len -= msg.msg_controllen;
1130 		return put_user(len, optlen);
1131 	}
1132 	case IP_FREEBIND:
1133 		val = inet->freebind;
1134 		break;
1135 	default:
1136 		release_sock(sk);
1137 		return -ENOPROTOOPT;
1138 	}
1139 	release_sock(sk);
1140 
1141 	if (len < sizeof(int) && len > 0 && val>=0 && val<=255) {
1142 		unsigned char ucval = (unsigned char)val;
1143 		len = 1;
1144 		if (put_user(len, optlen))
1145 			return -EFAULT;
1146 		if (copy_to_user(optval,&ucval,1))
1147 			return -EFAULT;
1148 	} else {
1149 		len = min_t(unsigned int, sizeof(int), len);
1150 		if (put_user(len, optlen))
1151 			return -EFAULT;
1152 		if (copy_to_user(optval,&val,len))
1153 			return -EFAULT;
1154 	}
1155 	return 0;
1156 }
1157 
1158 int ip_getsockopt(struct sock *sk, int level,
1159 		  int optname, char __user *optval, int __user *optlen)
1160 {
1161 	int err;
1162 
1163 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1164 #ifdef CONFIG_NETFILTER
1165 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1166 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1167 			!ip_mroute_opt(optname)) {
1168 		int len;
1169 
1170 		if (get_user(len,optlen))
1171 			return -EFAULT;
1172 
1173 		lock_sock(sk);
1174 		err = nf_getsockopt(sk, PF_INET, optname, optval,
1175 				&len);
1176 		release_sock(sk);
1177 		if (err >= 0)
1178 			err = put_user(len, optlen);
1179 		return err;
1180 	}
1181 #endif
1182 	return err;
1183 }
1184 
1185 #ifdef CONFIG_COMPAT
1186 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1187 			 char __user *optval, int __user *optlen)
1188 {
1189 	int err;
1190 
1191 	if (optname == MCAST_MSFILTER)
1192 		return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1193 			ip_getsockopt);
1194 
1195 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1196 
1197 #ifdef CONFIG_NETFILTER
1198 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1199 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1200 			!ip_mroute_opt(optname)) {
1201 		int len;
1202 
1203 		if (get_user(len, optlen))
1204 			return -EFAULT;
1205 
1206 		lock_sock(sk);
1207 		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1208 		release_sock(sk);
1209 		if (err >= 0)
1210 			err = put_user(len, optlen);
1211 		return err;
1212 	}
1213 #endif
1214 	return err;
1215 }
1216 
1217 EXPORT_SYMBOL(compat_ip_getsockopt);
1218 #endif
1219 
1220 EXPORT_SYMBOL(ip_cmsg_recv);
1221 
1222 EXPORT_SYMBOL(ip_getsockopt);
1223 EXPORT_SYMBOL(ip_setsockopt);
1224