xref: /openbmc/linux/net/ipv4/ip_sockglue.c (revision 643d1f7f)
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 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
40 #include <net/transp_v6.h>
41 #endif
42 
43 #include <linux/errqueue.h>
44 #include <asm/uaccess.h>
45 
46 #define IP_CMSG_PKTINFO		1
47 #define IP_CMSG_TTL		2
48 #define IP_CMSG_TOS		4
49 #define IP_CMSG_RECVOPTS	8
50 #define IP_CMSG_RETOPTS		16
51 #define IP_CMSG_PASSSEC		32
52 
53 /*
54  *	SOL_IP control messages.
55  */
56 
57 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
58 {
59 	struct in_pktinfo info;
60 	struct rtable *rt = (struct rtable *)skb->dst;
61 
62 	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
63 	if (rt) {
64 		info.ipi_ifindex = rt->rt_iif;
65 		info.ipi_spec_dst.s_addr = rt->rt_spec_dst;
66 	} else {
67 		info.ipi_ifindex = 0;
68 		info.ipi_spec_dst.s_addr = 0;
69 	}
70 
71 	put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
72 }
73 
74 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
75 {
76 	int ttl = ip_hdr(skb)->ttl;
77 	put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
78 }
79 
80 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
81 {
82 	put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
83 }
84 
85 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
86 {
87 	if (IPCB(skb)->opt.optlen == 0)
88 		return;
89 
90 	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
91 		 ip_hdr(skb) + 1);
92 }
93 
94 
95 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
96 {
97 	unsigned char optbuf[sizeof(struct ip_options) + 40];
98 	struct ip_options * opt = (struct ip_options*)optbuf;
99 
100 	if (IPCB(skb)->opt.optlen == 0)
101 		return;
102 
103 	if (ip_options_echo(opt, skb)) {
104 		msg->msg_flags |= MSG_CTRUNC;
105 		return;
106 	}
107 	ip_options_undo(opt);
108 
109 	put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
110 }
111 
112 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
113 {
114 	char *secdata;
115 	u32 seclen, secid;
116 	int err;
117 
118 	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
119 	if (err)
120 		return;
121 
122 	err = security_secid_to_secctx(secid, &secdata, &seclen);
123 	if (err)
124 		return;
125 
126 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
127 	security_release_secctx(secdata, seclen);
128 }
129 
130 
131 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
132 {
133 	struct inet_sock *inet = inet_sk(skb->sk);
134 	unsigned flags = inet->cmsg_flags;
135 
136 	/* Ordered by supposed usage frequency */
137 	if (flags & 1)
138 		ip_cmsg_recv_pktinfo(msg, skb);
139 	if ((flags>>=1) == 0)
140 		return;
141 
142 	if (flags & 1)
143 		ip_cmsg_recv_ttl(msg, skb);
144 	if ((flags>>=1) == 0)
145 		return;
146 
147 	if (flags & 1)
148 		ip_cmsg_recv_tos(msg, skb);
149 	if ((flags>>=1) == 0)
150 		return;
151 
152 	if (flags & 1)
153 		ip_cmsg_recv_opts(msg, skb);
154 	if ((flags>>=1) == 0)
155 		return;
156 
157 	if (flags & 1)
158 		ip_cmsg_recv_retopts(msg, skb);
159 	if ((flags>>=1) == 0)
160 		return;
161 
162 	if (flags & 1)
163 		ip_cmsg_recv_security(msg, skb);
164 }
165 
166 int ip_cmsg_send(struct msghdr *msg, struct ipcm_cookie *ipc)
167 {
168 	int err;
169 	struct cmsghdr *cmsg;
170 
171 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
172 		if (!CMSG_OK(msg, cmsg))
173 			return -EINVAL;
174 		if (cmsg->cmsg_level != SOL_IP)
175 			continue;
176 		switch (cmsg->cmsg_type) {
177 		case IP_RETOPTS:
178 			err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
179 			err = ip_options_get(&ipc->opt, CMSG_DATA(cmsg), err < 40 ? err : 40);
180 			if (err)
181 				return err;
182 			break;
183 		case IP_PKTINFO:
184 		{
185 			struct in_pktinfo *info;
186 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
187 				return -EINVAL;
188 			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
189 			ipc->oif = info->ipi_ifindex;
190 			ipc->addr = info->ipi_spec_dst.s_addr;
191 			break;
192 		}
193 		default:
194 			return -EINVAL;
195 		}
196 	}
197 	return 0;
198 }
199 
200 
201 /* Special input handler for packets caught by router alert option.
202    They are selected only by protocol field, and then processed likely
203    local ones; but only if someone wants them! Otherwise, router
204    not running rsvpd will kill RSVP.
205 
206    It is user level problem, what it will make with them.
207    I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
208    but receiver should be enough clever f.e. to forward mtrace requests,
209    sent to multicast group to reach destination designated router.
210  */
211 struct ip_ra_chain *ip_ra_chain;
212 DEFINE_RWLOCK(ip_ra_lock);
213 
214 int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *))
215 {
216 	struct ip_ra_chain *ra, *new_ra, **rap;
217 
218 	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num == IPPROTO_RAW)
219 		return -EINVAL;
220 
221 	new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
222 
223 	write_lock_bh(&ip_ra_lock);
224 	for (rap = &ip_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
225 		if (ra->sk == sk) {
226 			if (on) {
227 				write_unlock_bh(&ip_ra_lock);
228 				kfree(new_ra);
229 				return -EADDRINUSE;
230 			}
231 			*rap = ra->next;
232 			write_unlock_bh(&ip_ra_lock);
233 
234 			if (ra->destructor)
235 				ra->destructor(sk);
236 			sock_put(sk);
237 			kfree(ra);
238 			return 0;
239 		}
240 	}
241 	if (new_ra == NULL) {
242 		write_unlock_bh(&ip_ra_lock);
243 		return -ENOBUFS;
244 	}
245 	new_ra->sk = sk;
246 	new_ra->destructor = destructor;
247 
248 	new_ra->next = ra;
249 	*rap = new_ra;
250 	sock_hold(sk);
251 	write_unlock_bh(&ip_ra_lock);
252 
253 	return 0;
254 }
255 
256 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
257 		   __be16 port, u32 info, u8 *payload)
258 {
259 	struct inet_sock *inet = inet_sk(sk);
260 	struct sock_exterr_skb *serr;
261 
262 	if (!inet->recverr)
263 		return;
264 
265 	skb = skb_clone(skb, GFP_ATOMIC);
266 	if (!skb)
267 		return;
268 
269 	serr = SKB_EXT_ERR(skb);
270 	serr->ee.ee_errno = err;
271 	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
272 	serr->ee.ee_type = icmp_hdr(skb)->type;
273 	serr->ee.ee_code = icmp_hdr(skb)->code;
274 	serr->ee.ee_pad = 0;
275 	serr->ee.ee_info = info;
276 	serr->ee.ee_data = 0;
277 	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
278 				   skb_network_header(skb);
279 	serr->port = port;
280 
281 	if (skb_pull(skb, payload - skb->data) != NULL) {
282 		skb_reset_transport_header(skb);
283 		if (sock_queue_err_skb(sk, skb) == 0)
284 			return;
285 	}
286 	kfree_skb(skb);
287 }
288 
289 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
290 {
291 	struct inet_sock *inet = inet_sk(sk);
292 	struct sock_exterr_skb *serr;
293 	struct iphdr *iph;
294 	struct sk_buff *skb;
295 
296 	if (!inet->recverr)
297 		return;
298 
299 	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
300 	if (!skb)
301 		return;
302 
303 	skb_put(skb, sizeof(struct iphdr));
304 	skb_reset_network_header(skb);
305 	iph = ip_hdr(skb);
306 	iph->daddr = daddr;
307 
308 	serr = SKB_EXT_ERR(skb);
309 	serr->ee.ee_errno = err;
310 	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
311 	serr->ee.ee_type = 0;
312 	serr->ee.ee_code = 0;
313 	serr->ee.ee_pad = 0;
314 	serr->ee.ee_info = info;
315 	serr->ee.ee_data = 0;
316 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
317 	serr->port = port;
318 
319 	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
320 	skb_reset_transport_header(skb);
321 
322 	if (sock_queue_err_skb(sk, skb))
323 		kfree_skb(skb);
324 }
325 
326 /*
327  *	Handle MSG_ERRQUEUE
328  */
329 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
330 {
331 	struct sock_exterr_skb *serr;
332 	struct sk_buff *skb, *skb2;
333 	struct sockaddr_in *sin;
334 	struct {
335 		struct sock_extended_err ee;
336 		struct sockaddr_in	 offender;
337 	} errhdr;
338 	int err;
339 	int copied;
340 
341 	err = -EAGAIN;
342 	skb = skb_dequeue(&sk->sk_error_queue);
343 	if (skb == NULL)
344 		goto out;
345 
346 	copied = skb->len;
347 	if (copied > len) {
348 		msg->msg_flags |= MSG_TRUNC;
349 		copied = len;
350 	}
351 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
352 	if (err)
353 		goto out_free_skb;
354 
355 	sock_recv_timestamp(msg, sk, skb);
356 
357 	serr = SKB_EXT_ERR(skb);
358 
359 	sin = (struct sockaddr_in *)msg->msg_name;
360 	if (sin) {
361 		sin->sin_family = AF_INET;
362 		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
363 						   serr->addr_offset);
364 		sin->sin_port = serr->port;
365 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
366 	}
367 
368 	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
369 	sin = &errhdr.offender;
370 	sin->sin_family = AF_UNSPEC;
371 	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
372 		struct inet_sock *inet = inet_sk(sk);
373 
374 		sin->sin_family = AF_INET;
375 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
376 		sin->sin_port = 0;
377 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
378 		if (inet->cmsg_flags)
379 			ip_cmsg_recv(msg, skb);
380 	}
381 
382 	put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
383 
384 	/* Now we could try to dump offended packet options */
385 
386 	msg->msg_flags |= MSG_ERRQUEUE;
387 	err = copied;
388 
389 	/* Reset and regenerate socket error */
390 	spin_lock_bh(&sk->sk_error_queue.lock);
391 	sk->sk_err = 0;
392 	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
393 		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
394 		spin_unlock_bh(&sk->sk_error_queue.lock);
395 		sk->sk_error_report(sk);
396 	} else
397 		spin_unlock_bh(&sk->sk_error_queue.lock);
398 
399 out_free_skb:
400 	kfree_skb(skb);
401 out:
402 	return err;
403 }
404 
405 
406 /*
407  *	Socket option code for IP. This is the end of the line after any TCP,UDP etc options on
408  *	an IP socket.
409  */
410 
411 static int do_ip_setsockopt(struct sock *sk, int level,
412 			    int optname, char __user *optval, int optlen)
413 {
414 	struct inet_sock *inet = inet_sk(sk);
415 	int val=0,err;
416 
417 	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
418 			     (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
419 			     (1<<IP_RETOPTS) | (1<<IP_TOS) |
420 			     (1<<IP_TTL) | (1<<IP_HDRINCL) |
421 			     (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
422 			     (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
423 			     (1<<IP_PASSSEC))) ||
424 	    optname == IP_MULTICAST_TTL ||
425 	    optname == IP_MULTICAST_LOOP) {
426 		if (optlen >= sizeof(int)) {
427 			if (get_user(val, (int __user *) optval))
428 				return -EFAULT;
429 		} else if (optlen >= sizeof(char)) {
430 			unsigned char ucval;
431 
432 			if (get_user(ucval, (unsigned char __user *) optval))
433 				return -EFAULT;
434 			val = (int) ucval;
435 		}
436 	}
437 
438 	/* If optlen==0, it is equivalent to val == 0 */
439 
440 	if (ip_mroute_opt(optname))
441 		return ip_mroute_setsockopt(sk,optname,optval,optlen);
442 
443 	err = 0;
444 	lock_sock(sk);
445 
446 	switch (optname) {
447 	case IP_OPTIONS:
448 	{
449 		struct ip_options * opt = NULL;
450 		if (optlen > 40 || optlen < 0)
451 			goto e_inval;
452 		err = ip_options_get_from_user(&opt, optval, optlen);
453 		if (err)
454 			break;
455 		if (inet->is_icsk) {
456 			struct inet_connection_sock *icsk = inet_csk(sk);
457 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
458 			if (sk->sk_family == PF_INET ||
459 			    (!((1 << sk->sk_state) &
460 			       (TCPF_LISTEN | TCPF_CLOSE)) &&
461 			     inet->daddr != LOOPBACK4_IPV6)) {
462 #endif
463 				if (inet->opt)
464 					icsk->icsk_ext_hdr_len -= inet->opt->optlen;
465 				if (opt)
466 					icsk->icsk_ext_hdr_len += opt->optlen;
467 				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
468 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
469 			}
470 #endif
471 		}
472 		opt = xchg(&inet->opt, opt);
473 		kfree(opt);
474 		break;
475 	}
476 	case IP_PKTINFO:
477 		if (val)
478 			inet->cmsg_flags |= IP_CMSG_PKTINFO;
479 		else
480 			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
481 		break;
482 	case IP_RECVTTL:
483 		if (val)
484 			inet->cmsg_flags |=  IP_CMSG_TTL;
485 		else
486 			inet->cmsg_flags &= ~IP_CMSG_TTL;
487 		break;
488 	case IP_RECVTOS:
489 		if (val)
490 			inet->cmsg_flags |=  IP_CMSG_TOS;
491 		else
492 			inet->cmsg_flags &= ~IP_CMSG_TOS;
493 		break;
494 	case IP_RECVOPTS:
495 		if (val)
496 			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
497 		else
498 			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
499 		break;
500 	case IP_RETOPTS:
501 		if (val)
502 			inet->cmsg_flags |= IP_CMSG_RETOPTS;
503 		else
504 			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
505 		break;
506 	case IP_PASSSEC:
507 		if (val)
508 			inet->cmsg_flags |= IP_CMSG_PASSSEC;
509 		else
510 			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
511 		break;
512 	case IP_TOS:	/* This sets both TOS and Precedence */
513 		if (sk->sk_type == SOCK_STREAM) {
514 			val &= ~3;
515 			val |= inet->tos & 3;
516 		}
517 		if (IPTOS_PREC(val) >= IPTOS_PREC_CRITIC_ECP &&
518 		    !capable(CAP_NET_ADMIN)) {
519 			err = -EPERM;
520 			break;
521 		}
522 		if (inet->tos != val) {
523 			inet->tos = val;
524 			sk->sk_priority = rt_tos2priority(val);
525 			sk_dst_reset(sk);
526 		}
527 		break;
528 	case IP_TTL:
529 		if (optlen<1)
530 			goto e_inval;
531 		if (val != -1 && (val < 1 || val>255))
532 			goto e_inval;
533 		inet->uc_ttl = val;
534 		break;
535 	case IP_HDRINCL:
536 		if (sk->sk_type != SOCK_RAW) {
537 			err = -ENOPROTOOPT;
538 			break;
539 		}
540 		inet->hdrincl = val ? 1 : 0;
541 		break;
542 	case IP_MTU_DISCOVER:
543 		if (val<0 || val>3)
544 			goto e_inval;
545 		inet->pmtudisc = val;
546 		break;
547 	case IP_RECVERR:
548 		inet->recverr = !!val;
549 		if (!val)
550 			skb_queue_purge(&sk->sk_error_queue);
551 		break;
552 	case IP_MULTICAST_TTL:
553 		if (sk->sk_type == SOCK_STREAM)
554 			goto e_inval;
555 		if (optlen<1)
556 			goto e_inval;
557 		if (val==-1)
558 			val = 1;
559 		if (val < 0 || val > 255)
560 			goto e_inval;
561 		inet->mc_ttl = val;
562 		break;
563 	case IP_MULTICAST_LOOP:
564 		if (optlen<1)
565 			goto e_inval;
566 		inet->mc_loop = !!val;
567 		break;
568 	case IP_MULTICAST_IF:
569 	{
570 		struct ip_mreqn mreq;
571 		struct net_device *dev = NULL;
572 
573 		if (sk->sk_type == SOCK_STREAM)
574 			goto e_inval;
575 		/*
576 		 *	Check the arguments are allowable
577 		 */
578 
579 		err = -EFAULT;
580 		if (optlen >= sizeof(struct ip_mreqn)) {
581 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
582 				break;
583 		} else {
584 			memset(&mreq, 0, sizeof(mreq));
585 			if (optlen >= sizeof(struct in_addr) &&
586 			    copy_from_user(&mreq.imr_address,optval,sizeof(struct in_addr)))
587 				break;
588 		}
589 
590 		if (!mreq.imr_ifindex) {
591 			if (mreq.imr_address.s_addr == INADDR_ANY) {
592 				inet->mc_index = 0;
593 				inet->mc_addr  = 0;
594 				err = 0;
595 				break;
596 			}
597 			dev = ip_dev_find(&init_net, mreq.imr_address.s_addr);
598 			if (dev) {
599 				mreq.imr_ifindex = dev->ifindex;
600 				dev_put(dev);
601 			}
602 		} else
603 			dev = __dev_get_by_index(&init_net, mreq.imr_ifindex);
604 
605 
606 		err = -EADDRNOTAVAIL;
607 		if (!dev)
608 			break;
609 
610 		err = -EINVAL;
611 		if (sk->sk_bound_dev_if &&
612 		    mreq.imr_ifindex != sk->sk_bound_dev_if)
613 			break;
614 
615 		inet->mc_index = mreq.imr_ifindex;
616 		inet->mc_addr  = mreq.imr_address.s_addr;
617 		err = 0;
618 		break;
619 	}
620 
621 	case IP_ADD_MEMBERSHIP:
622 	case IP_DROP_MEMBERSHIP:
623 	{
624 		struct ip_mreqn mreq;
625 
626 		err = -EPROTO;
627 		if (inet_sk(sk)->is_icsk)
628 			break;
629 
630 		if (optlen < sizeof(struct ip_mreq))
631 			goto e_inval;
632 		err = -EFAULT;
633 		if (optlen >= sizeof(struct ip_mreqn)) {
634 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
635 				break;
636 		} else {
637 			memset(&mreq, 0, sizeof(mreq));
638 			if (copy_from_user(&mreq,optval,sizeof(struct ip_mreq)))
639 				break;
640 		}
641 
642 		if (optname == IP_ADD_MEMBERSHIP)
643 			err = ip_mc_join_group(sk, &mreq);
644 		else
645 			err = ip_mc_leave_group(sk, &mreq);
646 		break;
647 	}
648 	case IP_MSFILTER:
649 	{
650 		extern int sysctl_igmp_max_msf;
651 		struct ip_msfilter *msf;
652 
653 		if (optlen < IP_MSFILTER_SIZE(0))
654 			goto e_inval;
655 		if (optlen > sysctl_optmem_max) {
656 			err = -ENOBUFS;
657 			break;
658 		}
659 		msf = kmalloc(optlen, GFP_KERNEL);
660 		if (!msf) {
661 			err = -ENOBUFS;
662 			break;
663 		}
664 		err = -EFAULT;
665 		if (copy_from_user(msf, optval, optlen)) {
666 			kfree(msf);
667 			break;
668 		}
669 		/* numsrc >= (1G-4) overflow in 32 bits */
670 		if (msf->imsf_numsrc >= 0x3ffffffcU ||
671 		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
672 			kfree(msf);
673 			err = -ENOBUFS;
674 			break;
675 		}
676 		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
677 			kfree(msf);
678 			err = -EINVAL;
679 			break;
680 		}
681 		err = ip_mc_msfilter(sk, msf, 0);
682 		kfree(msf);
683 		break;
684 	}
685 	case IP_BLOCK_SOURCE:
686 	case IP_UNBLOCK_SOURCE:
687 	case IP_ADD_SOURCE_MEMBERSHIP:
688 	case IP_DROP_SOURCE_MEMBERSHIP:
689 	{
690 		struct ip_mreq_source mreqs;
691 		int omode, add;
692 
693 		if (optlen != sizeof(struct ip_mreq_source))
694 			goto e_inval;
695 		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
696 			err = -EFAULT;
697 			break;
698 		}
699 		if (optname == IP_BLOCK_SOURCE) {
700 			omode = MCAST_EXCLUDE;
701 			add = 1;
702 		} else if (optname == IP_UNBLOCK_SOURCE) {
703 			omode = MCAST_EXCLUDE;
704 			add = 0;
705 		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
706 			struct ip_mreqn mreq;
707 
708 			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
709 			mreq.imr_address.s_addr = mreqs.imr_interface;
710 			mreq.imr_ifindex = 0;
711 			err = ip_mc_join_group(sk, &mreq);
712 			if (err && err != -EADDRINUSE)
713 				break;
714 			omode = MCAST_INCLUDE;
715 			add = 1;
716 		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
717 			omode = MCAST_INCLUDE;
718 			add = 0;
719 		}
720 		err = ip_mc_source(add, omode, sk, &mreqs, 0);
721 		break;
722 	}
723 	case MCAST_JOIN_GROUP:
724 	case MCAST_LEAVE_GROUP:
725 	{
726 		struct group_req greq;
727 		struct sockaddr_in *psin;
728 		struct ip_mreqn mreq;
729 
730 		if (optlen < sizeof(struct group_req))
731 			goto e_inval;
732 		err = -EFAULT;
733 		if (copy_from_user(&greq, optval, sizeof(greq)))
734 			break;
735 		psin = (struct sockaddr_in *)&greq.gr_group;
736 		if (psin->sin_family != AF_INET)
737 			goto e_inval;
738 		memset(&mreq, 0, sizeof(mreq));
739 		mreq.imr_multiaddr = psin->sin_addr;
740 		mreq.imr_ifindex = greq.gr_interface;
741 
742 		if (optname == MCAST_JOIN_GROUP)
743 			err = ip_mc_join_group(sk, &mreq);
744 		else
745 			err = ip_mc_leave_group(sk, &mreq);
746 		break;
747 	}
748 	case MCAST_JOIN_SOURCE_GROUP:
749 	case MCAST_LEAVE_SOURCE_GROUP:
750 	case MCAST_BLOCK_SOURCE:
751 	case MCAST_UNBLOCK_SOURCE:
752 	{
753 		struct group_source_req greqs;
754 		struct ip_mreq_source mreqs;
755 		struct sockaddr_in *psin;
756 		int omode, add;
757 
758 		if (optlen != sizeof(struct group_source_req))
759 			goto e_inval;
760 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
761 			err = -EFAULT;
762 			break;
763 		}
764 		if (greqs.gsr_group.ss_family != AF_INET ||
765 		    greqs.gsr_source.ss_family != AF_INET) {
766 			err = -EADDRNOTAVAIL;
767 			break;
768 		}
769 		psin = (struct sockaddr_in *)&greqs.gsr_group;
770 		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
771 		psin = (struct sockaddr_in *)&greqs.gsr_source;
772 		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
773 		mreqs.imr_interface = 0; /* use index for mc_source */
774 
775 		if (optname == MCAST_BLOCK_SOURCE) {
776 			omode = MCAST_EXCLUDE;
777 			add = 1;
778 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
779 			omode = MCAST_EXCLUDE;
780 			add = 0;
781 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
782 			struct ip_mreqn mreq;
783 
784 			psin = (struct sockaddr_in *)&greqs.gsr_group;
785 			mreq.imr_multiaddr = psin->sin_addr;
786 			mreq.imr_address.s_addr = 0;
787 			mreq.imr_ifindex = greqs.gsr_interface;
788 			err = ip_mc_join_group(sk, &mreq);
789 			if (err && err != -EADDRINUSE)
790 				break;
791 			greqs.gsr_interface = mreq.imr_ifindex;
792 			omode = MCAST_INCLUDE;
793 			add = 1;
794 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
795 			omode = MCAST_INCLUDE;
796 			add = 0;
797 		}
798 		err = ip_mc_source(add, omode, sk, &mreqs,
799 				   greqs.gsr_interface);
800 		break;
801 	}
802 	case MCAST_MSFILTER:
803 	{
804 		extern int sysctl_igmp_max_msf;
805 		struct sockaddr_in *psin;
806 		struct ip_msfilter *msf = NULL;
807 		struct group_filter *gsf = NULL;
808 		int msize, i, ifindex;
809 
810 		if (optlen < GROUP_FILTER_SIZE(0))
811 			goto e_inval;
812 		if (optlen > sysctl_optmem_max) {
813 			err = -ENOBUFS;
814 			break;
815 		}
816 		gsf = kmalloc(optlen,GFP_KERNEL);
817 		if (!gsf) {
818 			err = -ENOBUFS;
819 			break;
820 		}
821 		err = -EFAULT;
822 		if (copy_from_user(gsf, optval, optlen)) {
823 			goto mc_msf_out;
824 		}
825 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
826 		if (gsf->gf_numsrc >= 0x1ffffff ||
827 		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
828 			err = -ENOBUFS;
829 			goto mc_msf_out;
830 		}
831 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
832 			err = -EINVAL;
833 			goto mc_msf_out;
834 		}
835 		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
836 		msf = kmalloc(msize,GFP_KERNEL);
837 		if (!msf) {
838 			err = -ENOBUFS;
839 			goto mc_msf_out;
840 		}
841 		ifindex = gsf->gf_interface;
842 		psin = (struct sockaddr_in *)&gsf->gf_group;
843 		if (psin->sin_family != AF_INET) {
844 			err = -EADDRNOTAVAIL;
845 			goto mc_msf_out;
846 		}
847 		msf->imsf_multiaddr = psin->sin_addr.s_addr;
848 		msf->imsf_interface = 0;
849 		msf->imsf_fmode = gsf->gf_fmode;
850 		msf->imsf_numsrc = gsf->gf_numsrc;
851 		err = -EADDRNOTAVAIL;
852 		for (i=0; i<gsf->gf_numsrc; ++i) {
853 			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
854 
855 			if (psin->sin_family != AF_INET)
856 				goto mc_msf_out;
857 			msf->imsf_slist[i] = psin->sin_addr.s_addr;
858 		}
859 		kfree(gsf);
860 		gsf = NULL;
861 
862 		err = ip_mc_msfilter(sk, msf, ifindex);
863 	mc_msf_out:
864 		kfree(msf);
865 		kfree(gsf);
866 		break;
867 	}
868 	case IP_ROUTER_ALERT:
869 		err = ip_ra_control(sk, val ? 1 : 0, NULL);
870 		break;
871 
872 	case IP_FREEBIND:
873 		if (optlen<1)
874 			goto e_inval;
875 		inet->freebind = !!val;
876 		break;
877 
878 	case IP_IPSEC_POLICY:
879 	case IP_XFRM_POLICY:
880 		err = -EPERM;
881 		if (!capable(CAP_NET_ADMIN))
882 			break;
883 		err = xfrm_user_policy(sk, optname, optval, optlen);
884 		break;
885 
886 	default:
887 		err = -ENOPROTOOPT;
888 		break;
889 	}
890 	release_sock(sk);
891 	return err;
892 
893 e_inval:
894 	release_sock(sk);
895 	return -EINVAL;
896 }
897 
898 int ip_setsockopt(struct sock *sk, int level,
899 		int optname, char __user *optval, int optlen)
900 {
901 	int err;
902 
903 	if (level != SOL_IP)
904 		return -ENOPROTOOPT;
905 
906 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
907 #ifdef CONFIG_NETFILTER
908 	/* we need to exclude all possible ENOPROTOOPTs except default case */
909 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
910 			optname != IP_IPSEC_POLICY &&
911 			optname != IP_XFRM_POLICY &&
912 			!ip_mroute_opt(optname)) {
913 		lock_sock(sk);
914 		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
915 		release_sock(sk);
916 	}
917 #endif
918 	return err;
919 }
920 
921 #ifdef CONFIG_COMPAT
922 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
923 			 char __user *optval, int optlen)
924 {
925 	int err;
926 
927 	if (level != SOL_IP)
928 		return -ENOPROTOOPT;
929 
930 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
931 #ifdef CONFIG_NETFILTER
932 	/* we need to exclude all possible ENOPROTOOPTs except default case */
933 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
934 			optname != IP_IPSEC_POLICY &&
935 			optname != IP_XFRM_POLICY &&
936 			!ip_mroute_opt(optname)) {
937 		lock_sock(sk);
938 		err = compat_nf_setsockopt(sk, PF_INET, optname,
939 					   optval, optlen);
940 		release_sock(sk);
941 	}
942 #endif
943 	return err;
944 }
945 
946 EXPORT_SYMBOL(compat_ip_setsockopt);
947 #endif
948 
949 /*
950  *	Get the options. Note for future reference. The GET of IP options gets the
951  *	_received_ ones. The set sets the _sent_ ones.
952  */
953 
954 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
955 			    char __user *optval, int __user *optlen)
956 {
957 	struct inet_sock *inet = inet_sk(sk);
958 	int val;
959 	int len;
960 
961 	if (level != SOL_IP)
962 		return -EOPNOTSUPP;
963 
964 	if (ip_mroute_opt(optname))
965 		return ip_mroute_getsockopt(sk,optname,optval,optlen);
966 
967 	if (get_user(len,optlen))
968 		return -EFAULT;
969 	if (len < 0)
970 		return -EINVAL;
971 
972 	lock_sock(sk);
973 
974 	switch (optname) {
975 	case IP_OPTIONS:
976 	{
977 		unsigned char optbuf[sizeof(struct ip_options)+40];
978 		struct ip_options * opt = (struct ip_options*)optbuf;
979 		opt->optlen = 0;
980 		if (inet->opt)
981 			memcpy(optbuf, inet->opt,
982 			       sizeof(struct ip_options)+
983 			       inet->opt->optlen);
984 		release_sock(sk);
985 
986 		if (opt->optlen == 0)
987 			return put_user(0, optlen);
988 
989 		ip_options_undo(opt);
990 
991 		len = min_t(unsigned int, len, opt->optlen);
992 		if (put_user(len, optlen))
993 			return -EFAULT;
994 		if (copy_to_user(optval, opt->__data, len))
995 			return -EFAULT;
996 		return 0;
997 	}
998 	case IP_PKTINFO:
999 		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1000 		break;
1001 	case IP_RECVTTL:
1002 		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1003 		break;
1004 	case IP_RECVTOS:
1005 		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1006 		break;
1007 	case IP_RECVOPTS:
1008 		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1009 		break;
1010 	case IP_RETOPTS:
1011 		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1012 		break;
1013 	case IP_PASSSEC:
1014 		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1015 		break;
1016 	case IP_TOS:
1017 		val = inet->tos;
1018 		break;
1019 	case IP_TTL:
1020 		val = (inet->uc_ttl == -1 ?
1021 		       sysctl_ip_default_ttl :
1022 		       inet->uc_ttl);
1023 		break;
1024 	case IP_HDRINCL:
1025 		val = inet->hdrincl;
1026 		break;
1027 	case IP_MTU_DISCOVER:
1028 		val = inet->pmtudisc;
1029 		break;
1030 	case IP_MTU:
1031 	{
1032 		struct dst_entry *dst;
1033 		val = 0;
1034 		dst = sk_dst_get(sk);
1035 		if (dst) {
1036 			val = dst_mtu(dst);
1037 			dst_release(dst);
1038 		}
1039 		if (!val) {
1040 			release_sock(sk);
1041 			return -ENOTCONN;
1042 		}
1043 		break;
1044 	}
1045 	case IP_RECVERR:
1046 		val = inet->recverr;
1047 		break;
1048 	case IP_MULTICAST_TTL:
1049 		val = inet->mc_ttl;
1050 		break;
1051 	case IP_MULTICAST_LOOP:
1052 		val = inet->mc_loop;
1053 		break;
1054 	case IP_MULTICAST_IF:
1055 	{
1056 		struct in_addr addr;
1057 		len = min_t(unsigned int, len, sizeof(struct in_addr));
1058 		addr.s_addr = inet->mc_addr;
1059 		release_sock(sk);
1060 
1061 		if (put_user(len, optlen))
1062 			return -EFAULT;
1063 		if (copy_to_user(optval, &addr, len))
1064 			return -EFAULT;
1065 		return 0;
1066 	}
1067 	case IP_MSFILTER:
1068 	{
1069 		struct ip_msfilter msf;
1070 		int err;
1071 
1072 		if (len < IP_MSFILTER_SIZE(0)) {
1073 			release_sock(sk);
1074 			return -EINVAL;
1075 		}
1076 		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1077 			release_sock(sk);
1078 			return -EFAULT;
1079 		}
1080 		err = ip_mc_msfget(sk, &msf,
1081 				   (struct ip_msfilter __user *)optval, optlen);
1082 		release_sock(sk);
1083 		return err;
1084 	}
1085 	case MCAST_MSFILTER:
1086 	{
1087 		struct group_filter gsf;
1088 		int err;
1089 
1090 		if (len < GROUP_FILTER_SIZE(0)) {
1091 			release_sock(sk);
1092 			return -EINVAL;
1093 		}
1094 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1095 			release_sock(sk);
1096 			return -EFAULT;
1097 		}
1098 		err = ip_mc_gsfget(sk, &gsf,
1099 				   (struct group_filter __user *)optval, optlen);
1100 		release_sock(sk);
1101 		return err;
1102 	}
1103 	case IP_PKTOPTIONS:
1104 	{
1105 		struct msghdr msg;
1106 
1107 		release_sock(sk);
1108 
1109 		if (sk->sk_type != SOCK_STREAM)
1110 			return -ENOPROTOOPT;
1111 
1112 		msg.msg_control = optval;
1113 		msg.msg_controllen = len;
1114 		msg.msg_flags = 0;
1115 
1116 		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1117 			struct in_pktinfo info;
1118 
1119 			info.ipi_addr.s_addr = inet->rcv_saddr;
1120 			info.ipi_spec_dst.s_addr = inet->rcv_saddr;
1121 			info.ipi_ifindex = inet->mc_index;
1122 			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1123 		}
1124 		if (inet->cmsg_flags & IP_CMSG_TTL) {
1125 			int hlim = inet->mc_ttl;
1126 			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1127 		}
1128 		len -= msg.msg_controllen;
1129 		return put_user(len, optlen);
1130 	}
1131 	case IP_FREEBIND:
1132 		val = inet->freebind;
1133 		break;
1134 	default:
1135 		release_sock(sk);
1136 		return -ENOPROTOOPT;
1137 	}
1138 	release_sock(sk);
1139 
1140 	if (len < sizeof(int) && len > 0 && val>=0 && val<255) {
1141 		unsigned char ucval = (unsigned char)val;
1142 		len = 1;
1143 		if (put_user(len, optlen))
1144 			return -EFAULT;
1145 		if (copy_to_user(optval,&ucval,1))
1146 			return -EFAULT;
1147 	} else {
1148 		len = min_t(unsigned int, sizeof(int), len);
1149 		if (put_user(len, optlen))
1150 			return -EFAULT;
1151 		if (copy_to_user(optval,&val,len))
1152 			return -EFAULT;
1153 	}
1154 	return 0;
1155 }
1156 
1157 int ip_getsockopt(struct sock *sk, int level,
1158 		  int optname, char __user *optval, int __user *optlen)
1159 {
1160 	int err;
1161 
1162 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1163 #ifdef CONFIG_NETFILTER
1164 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1165 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1166 			!ip_mroute_opt(optname)) {
1167 		int len;
1168 
1169 		if (get_user(len,optlen))
1170 			return -EFAULT;
1171 
1172 		lock_sock(sk);
1173 		err = nf_getsockopt(sk, PF_INET, optname, optval,
1174 				&len);
1175 		release_sock(sk);
1176 		if (err >= 0)
1177 			err = put_user(len, optlen);
1178 		return err;
1179 	}
1180 #endif
1181 	return err;
1182 }
1183 
1184 #ifdef CONFIG_COMPAT
1185 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1186 			 char __user *optval, int __user *optlen)
1187 {
1188 	int err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1189 #ifdef CONFIG_NETFILTER
1190 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1191 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1192 			!ip_mroute_opt(optname)) {
1193 		int len;
1194 
1195 		if (get_user(len, optlen))
1196 			return -EFAULT;
1197 
1198 		lock_sock(sk);
1199 		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1200 		release_sock(sk);
1201 		if (err >= 0)
1202 			err = put_user(len, optlen);
1203 		return err;
1204 	}
1205 #endif
1206 	return err;
1207 }
1208 
1209 EXPORT_SYMBOL(compat_ip_getsockopt);
1210 #endif
1211 
1212 EXPORT_SYMBOL(ip_cmsg_recv);
1213 
1214 EXPORT_SYMBOL(ip_getsockopt);
1215 EXPORT_SYMBOL(ip_setsockopt);
1216