xref: /openbmc/linux/net/ipv4/ip_sockglue.c (revision f42b3800)
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 = skb->rtable;
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 net *net, 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(net, &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(sock_net(sk), &opt,
453 					       optval, optlen);
454 		if (err)
455 			break;
456 		if (inet->is_icsk) {
457 			struct inet_connection_sock *icsk = inet_csk(sk);
458 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
459 			if (sk->sk_family == PF_INET ||
460 			    (!((1 << sk->sk_state) &
461 			       (TCPF_LISTEN | TCPF_CLOSE)) &&
462 			     inet->daddr != LOOPBACK4_IPV6)) {
463 #endif
464 				if (inet->opt)
465 					icsk->icsk_ext_hdr_len -= inet->opt->optlen;
466 				if (opt)
467 					icsk->icsk_ext_hdr_len += opt->optlen;
468 				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
469 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
470 			}
471 #endif
472 		}
473 		opt = xchg(&inet->opt, opt);
474 		kfree(opt);
475 		break;
476 	}
477 	case IP_PKTINFO:
478 		if (val)
479 			inet->cmsg_flags |= IP_CMSG_PKTINFO;
480 		else
481 			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
482 		break;
483 	case IP_RECVTTL:
484 		if (val)
485 			inet->cmsg_flags |=  IP_CMSG_TTL;
486 		else
487 			inet->cmsg_flags &= ~IP_CMSG_TTL;
488 		break;
489 	case IP_RECVTOS:
490 		if (val)
491 			inet->cmsg_flags |=  IP_CMSG_TOS;
492 		else
493 			inet->cmsg_flags &= ~IP_CMSG_TOS;
494 		break;
495 	case IP_RECVOPTS:
496 		if (val)
497 			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
498 		else
499 			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
500 		break;
501 	case IP_RETOPTS:
502 		if (val)
503 			inet->cmsg_flags |= IP_CMSG_RETOPTS;
504 		else
505 			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
506 		break;
507 	case IP_PASSSEC:
508 		if (val)
509 			inet->cmsg_flags |= IP_CMSG_PASSSEC;
510 		else
511 			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
512 		break;
513 	case IP_TOS:	/* This sets both TOS and Precedence */
514 		if (sk->sk_type == SOCK_STREAM) {
515 			val &= ~3;
516 			val |= inet->tos & 3;
517 		}
518 		if (inet->tos != val) {
519 			inet->tos = val;
520 			sk->sk_priority = rt_tos2priority(val);
521 			sk_dst_reset(sk);
522 		}
523 		break;
524 	case IP_TTL:
525 		if (optlen<1)
526 			goto e_inval;
527 		if (val != -1 && (val < 1 || val>255))
528 			goto e_inval;
529 		inet->uc_ttl = val;
530 		break;
531 	case IP_HDRINCL:
532 		if (sk->sk_type != SOCK_RAW) {
533 			err = -ENOPROTOOPT;
534 			break;
535 		}
536 		inet->hdrincl = val ? 1 : 0;
537 		break;
538 	case IP_MTU_DISCOVER:
539 		if (val<0 || val>3)
540 			goto e_inval;
541 		inet->pmtudisc = val;
542 		break;
543 	case IP_RECVERR:
544 		inet->recverr = !!val;
545 		if (!val)
546 			skb_queue_purge(&sk->sk_error_queue);
547 		break;
548 	case IP_MULTICAST_TTL:
549 		if (sk->sk_type == SOCK_STREAM)
550 			goto e_inval;
551 		if (optlen<1)
552 			goto e_inval;
553 		if (val==-1)
554 			val = 1;
555 		if (val < 0 || val > 255)
556 			goto e_inval;
557 		inet->mc_ttl = val;
558 		break;
559 	case IP_MULTICAST_LOOP:
560 		if (optlen<1)
561 			goto e_inval;
562 		inet->mc_loop = !!val;
563 		break;
564 	case IP_MULTICAST_IF:
565 	{
566 		struct ip_mreqn mreq;
567 		struct net_device *dev = NULL;
568 
569 		if (sk->sk_type == SOCK_STREAM)
570 			goto e_inval;
571 		/*
572 		 *	Check the arguments are allowable
573 		 */
574 
575 		err = -EFAULT;
576 		if (optlen >= sizeof(struct ip_mreqn)) {
577 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
578 				break;
579 		} else {
580 			memset(&mreq, 0, sizeof(mreq));
581 			if (optlen >= sizeof(struct in_addr) &&
582 			    copy_from_user(&mreq.imr_address,optval,sizeof(struct in_addr)))
583 				break;
584 		}
585 
586 		if (!mreq.imr_ifindex) {
587 			if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
588 				inet->mc_index = 0;
589 				inet->mc_addr  = 0;
590 				err = 0;
591 				break;
592 			}
593 			dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
594 			if (dev) {
595 				mreq.imr_ifindex = dev->ifindex;
596 				dev_put(dev);
597 			}
598 		} else
599 			dev = __dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
600 
601 
602 		err = -EADDRNOTAVAIL;
603 		if (!dev)
604 			break;
605 
606 		err = -EINVAL;
607 		if (sk->sk_bound_dev_if &&
608 		    mreq.imr_ifindex != sk->sk_bound_dev_if)
609 			break;
610 
611 		inet->mc_index = mreq.imr_ifindex;
612 		inet->mc_addr  = mreq.imr_address.s_addr;
613 		err = 0;
614 		break;
615 	}
616 
617 	case IP_ADD_MEMBERSHIP:
618 	case IP_DROP_MEMBERSHIP:
619 	{
620 		struct ip_mreqn mreq;
621 
622 		err = -EPROTO;
623 		if (inet_sk(sk)->is_icsk)
624 			break;
625 
626 		if (optlen < sizeof(struct ip_mreq))
627 			goto e_inval;
628 		err = -EFAULT;
629 		if (optlen >= sizeof(struct ip_mreqn)) {
630 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
631 				break;
632 		} else {
633 			memset(&mreq, 0, sizeof(mreq));
634 			if (copy_from_user(&mreq,optval,sizeof(struct ip_mreq)))
635 				break;
636 		}
637 
638 		if (optname == IP_ADD_MEMBERSHIP)
639 			err = ip_mc_join_group(sk, &mreq);
640 		else
641 			err = ip_mc_leave_group(sk, &mreq);
642 		break;
643 	}
644 	case IP_MSFILTER:
645 	{
646 		extern int sysctl_igmp_max_msf;
647 		struct ip_msfilter *msf;
648 
649 		if (optlen < IP_MSFILTER_SIZE(0))
650 			goto e_inval;
651 		if (optlen > sysctl_optmem_max) {
652 			err = -ENOBUFS;
653 			break;
654 		}
655 		msf = kmalloc(optlen, GFP_KERNEL);
656 		if (!msf) {
657 			err = -ENOBUFS;
658 			break;
659 		}
660 		err = -EFAULT;
661 		if (copy_from_user(msf, optval, optlen)) {
662 			kfree(msf);
663 			break;
664 		}
665 		/* numsrc >= (1G-4) overflow in 32 bits */
666 		if (msf->imsf_numsrc >= 0x3ffffffcU ||
667 		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
668 			kfree(msf);
669 			err = -ENOBUFS;
670 			break;
671 		}
672 		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
673 			kfree(msf);
674 			err = -EINVAL;
675 			break;
676 		}
677 		err = ip_mc_msfilter(sk, msf, 0);
678 		kfree(msf);
679 		break;
680 	}
681 	case IP_BLOCK_SOURCE:
682 	case IP_UNBLOCK_SOURCE:
683 	case IP_ADD_SOURCE_MEMBERSHIP:
684 	case IP_DROP_SOURCE_MEMBERSHIP:
685 	{
686 		struct ip_mreq_source mreqs;
687 		int omode, add;
688 
689 		if (optlen != sizeof(struct ip_mreq_source))
690 			goto e_inval;
691 		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
692 			err = -EFAULT;
693 			break;
694 		}
695 		if (optname == IP_BLOCK_SOURCE) {
696 			omode = MCAST_EXCLUDE;
697 			add = 1;
698 		} else if (optname == IP_UNBLOCK_SOURCE) {
699 			omode = MCAST_EXCLUDE;
700 			add = 0;
701 		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
702 			struct ip_mreqn mreq;
703 
704 			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
705 			mreq.imr_address.s_addr = mreqs.imr_interface;
706 			mreq.imr_ifindex = 0;
707 			err = ip_mc_join_group(sk, &mreq);
708 			if (err && err != -EADDRINUSE)
709 				break;
710 			omode = MCAST_INCLUDE;
711 			add = 1;
712 		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
713 			omode = MCAST_INCLUDE;
714 			add = 0;
715 		}
716 		err = ip_mc_source(add, omode, sk, &mreqs, 0);
717 		break;
718 	}
719 	case MCAST_JOIN_GROUP:
720 	case MCAST_LEAVE_GROUP:
721 	{
722 		struct group_req greq;
723 		struct sockaddr_in *psin;
724 		struct ip_mreqn mreq;
725 
726 		if (optlen < sizeof(struct group_req))
727 			goto e_inval;
728 		err = -EFAULT;
729 		if (copy_from_user(&greq, optval, sizeof(greq)))
730 			break;
731 		psin = (struct sockaddr_in *)&greq.gr_group;
732 		if (psin->sin_family != AF_INET)
733 			goto e_inval;
734 		memset(&mreq, 0, sizeof(mreq));
735 		mreq.imr_multiaddr = psin->sin_addr;
736 		mreq.imr_ifindex = greq.gr_interface;
737 
738 		if (optname == MCAST_JOIN_GROUP)
739 			err = ip_mc_join_group(sk, &mreq);
740 		else
741 			err = ip_mc_leave_group(sk, &mreq);
742 		break;
743 	}
744 	case MCAST_JOIN_SOURCE_GROUP:
745 	case MCAST_LEAVE_SOURCE_GROUP:
746 	case MCAST_BLOCK_SOURCE:
747 	case MCAST_UNBLOCK_SOURCE:
748 	{
749 		struct group_source_req greqs;
750 		struct ip_mreq_source mreqs;
751 		struct sockaddr_in *psin;
752 		int omode, add;
753 
754 		if (optlen != sizeof(struct group_source_req))
755 			goto e_inval;
756 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
757 			err = -EFAULT;
758 			break;
759 		}
760 		if (greqs.gsr_group.ss_family != AF_INET ||
761 		    greqs.gsr_source.ss_family != AF_INET) {
762 			err = -EADDRNOTAVAIL;
763 			break;
764 		}
765 		psin = (struct sockaddr_in *)&greqs.gsr_group;
766 		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
767 		psin = (struct sockaddr_in *)&greqs.gsr_source;
768 		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
769 		mreqs.imr_interface = 0; /* use index for mc_source */
770 
771 		if (optname == MCAST_BLOCK_SOURCE) {
772 			omode = MCAST_EXCLUDE;
773 			add = 1;
774 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
775 			omode = MCAST_EXCLUDE;
776 			add = 0;
777 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
778 			struct ip_mreqn mreq;
779 
780 			psin = (struct sockaddr_in *)&greqs.gsr_group;
781 			mreq.imr_multiaddr = psin->sin_addr;
782 			mreq.imr_address.s_addr = 0;
783 			mreq.imr_ifindex = greqs.gsr_interface;
784 			err = ip_mc_join_group(sk, &mreq);
785 			if (err && err != -EADDRINUSE)
786 				break;
787 			greqs.gsr_interface = mreq.imr_ifindex;
788 			omode = MCAST_INCLUDE;
789 			add = 1;
790 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
791 			omode = MCAST_INCLUDE;
792 			add = 0;
793 		}
794 		err = ip_mc_source(add, omode, sk, &mreqs,
795 				   greqs.gsr_interface);
796 		break;
797 	}
798 	case MCAST_MSFILTER:
799 	{
800 		extern int sysctl_igmp_max_msf;
801 		struct sockaddr_in *psin;
802 		struct ip_msfilter *msf = NULL;
803 		struct group_filter *gsf = NULL;
804 		int msize, i, ifindex;
805 
806 		if (optlen < GROUP_FILTER_SIZE(0))
807 			goto e_inval;
808 		if (optlen > sysctl_optmem_max) {
809 			err = -ENOBUFS;
810 			break;
811 		}
812 		gsf = kmalloc(optlen,GFP_KERNEL);
813 		if (!gsf) {
814 			err = -ENOBUFS;
815 			break;
816 		}
817 		err = -EFAULT;
818 		if (copy_from_user(gsf, optval, optlen)) {
819 			goto mc_msf_out;
820 		}
821 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
822 		if (gsf->gf_numsrc >= 0x1ffffff ||
823 		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
824 			err = -ENOBUFS;
825 			goto mc_msf_out;
826 		}
827 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
828 			err = -EINVAL;
829 			goto mc_msf_out;
830 		}
831 		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
832 		msf = kmalloc(msize,GFP_KERNEL);
833 		if (!msf) {
834 			err = -ENOBUFS;
835 			goto mc_msf_out;
836 		}
837 		ifindex = gsf->gf_interface;
838 		psin = (struct sockaddr_in *)&gsf->gf_group;
839 		if (psin->sin_family != AF_INET) {
840 			err = -EADDRNOTAVAIL;
841 			goto mc_msf_out;
842 		}
843 		msf->imsf_multiaddr = psin->sin_addr.s_addr;
844 		msf->imsf_interface = 0;
845 		msf->imsf_fmode = gsf->gf_fmode;
846 		msf->imsf_numsrc = gsf->gf_numsrc;
847 		err = -EADDRNOTAVAIL;
848 		for (i=0; i<gsf->gf_numsrc; ++i) {
849 			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
850 
851 			if (psin->sin_family != AF_INET)
852 				goto mc_msf_out;
853 			msf->imsf_slist[i] = psin->sin_addr.s_addr;
854 		}
855 		kfree(gsf);
856 		gsf = NULL;
857 
858 		err = ip_mc_msfilter(sk, msf, ifindex);
859 	mc_msf_out:
860 		kfree(msf);
861 		kfree(gsf);
862 		break;
863 	}
864 	case IP_ROUTER_ALERT:
865 		err = ip_ra_control(sk, val ? 1 : 0, NULL);
866 		break;
867 
868 	case IP_FREEBIND:
869 		if (optlen<1)
870 			goto e_inval;
871 		inet->freebind = !!val;
872 		break;
873 
874 	case IP_IPSEC_POLICY:
875 	case IP_XFRM_POLICY:
876 		err = -EPERM;
877 		if (!capable(CAP_NET_ADMIN))
878 			break;
879 		err = xfrm_user_policy(sk, optname, optval, optlen);
880 		break;
881 
882 	default:
883 		err = -ENOPROTOOPT;
884 		break;
885 	}
886 	release_sock(sk);
887 	return err;
888 
889 e_inval:
890 	release_sock(sk);
891 	return -EINVAL;
892 }
893 
894 int ip_setsockopt(struct sock *sk, int level,
895 		int optname, char __user *optval, int optlen)
896 {
897 	int err;
898 
899 	if (level != SOL_IP)
900 		return -ENOPROTOOPT;
901 
902 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
903 #ifdef CONFIG_NETFILTER
904 	/* we need to exclude all possible ENOPROTOOPTs except default case */
905 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
906 			optname != IP_IPSEC_POLICY &&
907 			optname != IP_XFRM_POLICY &&
908 			!ip_mroute_opt(optname)) {
909 		lock_sock(sk);
910 		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
911 		release_sock(sk);
912 	}
913 #endif
914 	return err;
915 }
916 
917 #ifdef CONFIG_COMPAT
918 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
919 			 char __user *optval, int optlen)
920 {
921 	int err;
922 
923 	if (level != SOL_IP)
924 		return -ENOPROTOOPT;
925 
926 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
927 #ifdef CONFIG_NETFILTER
928 	/* we need to exclude all possible ENOPROTOOPTs except default case */
929 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
930 			optname != IP_IPSEC_POLICY &&
931 			optname != IP_XFRM_POLICY &&
932 			!ip_mroute_opt(optname)) {
933 		lock_sock(sk);
934 		err = compat_nf_setsockopt(sk, PF_INET, optname,
935 					   optval, optlen);
936 		release_sock(sk);
937 	}
938 #endif
939 	return err;
940 }
941 
942 EXPORT_SYMBOL(compat_ip_setsockopt);
943 #endif
944 
945 /*
946  *	Get the options. Note for future reference. The GET of IP options gets the
947  *	_received_ ones. The set sets the _sent_ ones.
948  */
949 
950 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
951 			    char __user *optval, int __user *optlen)
952 {
953 	struct inet_sock *inet = inet_sk(sk);
954 	int val;
955 	int len;
956 
957 	if (level != SOL_IP)
958 		return -EOPNOTSUPP;
959 
960 	if (ip_mroute_opt(optname))
961 		return ip_mroute_getsockopt(sk,optname,optval,optlen);
962 
963 	if (get_user(len,optlen))
964 		return -EFAULT;
965 	if (len < 0)
966 		return -EINVAL;
967 
968 	lock_sock(sk);
969 
970 	switch (optname) {
971 	case IP_OPTIONS:
972 	{
973 		unsigned char optbuf[sizeof(struct ip_options)+40];
974 		struct ip_options * opt = (struct ip_options*)optbuf;
975 		opt->optlen = 0;
976 		if (inet->opt)
977 			memcpy(optbuf, inet->opt,
978 			       sizeof(struct ip_options)+
979 			       inet->opt->optlen);
980 		release_sock(sk);
981 
982 		if (opt->optlen == 0)
983 			return put_user(0, optlen);
984 
985 		ip_options_undo(opt);
986 
987 		len = min_t(unsigned int, len, opt->optlen);
988 		if (put_user(len, optlen))
989 			return -EFAULT;
990 		if (copy_to_user(optval, opt->__data, len))
991 			return -EFAULT;
992 		return 0;
993 	}
994 	case IP_PKTINFO:
995 		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
996 		break;
997 	case IP_RECVTTL:
998 		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
999 		break;
1000 	case IP_RECVTOS:
1001 		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1002 		break;
1003 	case IP_RECVOPTS:
1004 		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1005 		break;
1006 	case IP_RETOPTS:
1007 		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1008 		break;
1009 	case IP_PASSSEC:
1010 		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1011 		break;
1012 	case IP_TOS:
1013 		val = inet->tos;
1014 		break;
1015 	case IP_TTL:
1016 		val = (inet->uc_ttl == -1 ?
1017 		       sysctl_ip_default_ttl :
1018 		       inet->uc_ttl);
1019 		break;
1020 	case IP_HDRINCL:
1021 		val = inet->hdrincl;
1022 		break;
1023 	case IP_MTU_DISCOVER:
1024 		val = inet->pmtudisc;
1025 		break;
1026 	case IP_MTU:
1027 	{
1028 		struct dst_entry *dst;
1029 		val = 0;
1030 		dst = sk_dst_get(sk);
1031 		if (dst) {
1032 			val = dst_mtu(dst);
1033 			dst_release(dst);
1034 		}
1035 		if (!val) {
1036 			release_sock(sk);
1037 			return -ENOTCONN;
1038 		}
1039 		break;
1040 	}
1041 	case IP_RECVERR:
1042 		val = inet->recverr;
1043 		break;
1044 	case IP_MULTICAST_TTL:
1045 		val = inet->mc_ttl;
1046 		break;
1047 	case IP_MULTICAST_LOOP:
1048 		val = inet->mc_loop;
1049 		break;
1050 	case IP_MULTICAST_IF:
1051 	{
1052 		struct in_addr addr;
1053 		len = min_t(unsigned int, len, sizeof(struct in_addr));
1054 		addr.s_addr = inet->mc_addr;
1055 		release_sock(sk);
1056 
1057 		if (put_user(len, optlen))
1058 			return -EFAULT;
1059 		if (copy_to_user(optval, &addr, len))
1060 			return -EFAULT;
1061 		return 0;
1062 	}
1063 	case IP_MSFILTER:
1064 	{
1065 		struct ip_msfilter msf;
1066 		int err;
1067 
1068 		if (len < IP_MSFILTER_SIZE(0)) {
1069 			release_sock(sk);
1070 			return -EINVAL;
1071 		}
1072 		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1073 			release_sock(sk);
1074 			return -EFAULT;
1075 		}
1076 		err = ip_mc_msfget(sk, &msf,
1077 				   (struct ip_msfilter __user *)optval, optlen);
1078 		release_sock(sk);
1079 		return err;
1080 	}
1081 	case MCAST_MSFILTER:
1082 	{
1083 		struct group_filter gsf;
1084 		int err;
1085 
1086 		if (len < GROUP_FILTER_SIZE(0)) {
1087 			release_sock(sk);
1088 			return -EINVAL;
1089 		}
1090 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1091 			release_sock(sk);
1092 			return -EFAULT;
1093 		}
1094 		err = ip_mc_gsfget(sk, &gsf,
1095 				   (struct group_filter __user *)optval, optlen);
1096 		release_sock(sk);
1097 		return err;
1098 	}
1099 	case IP_PKTOPTIONS:
1100 	{
1101 		struct msghdr msg;
1102 
1103 		release_sock(sk);
1104 
1105 		if (sk->sk_type != SOCK_STREAM)
1106 			return -ENOPROTOOPT;
1107 
1108 		msg.msg_control = optval;
1109 		msg.msg_controllen = len;
1110 		msg.msg_flags = 0;
1111 
1112 		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1113 			struct in_pktinfo info;
1114 
1115 			info.ipi_addr.s_addr = inet->rcv_saddr;
1116 			info.ipi_spec_dst.s_addr = inet->rcv_saddr;
1117 			info.ipi_ifindex = inet->mc_index;
1118 			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1119 		}
1120 		if (inet->cmsg_flags & IP_CMSG_TTL) {
1121 			int hlim = inet->mc_ttl;
1122 			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1123 		}
1124 		len -= msg.msg_controllen;
1125 		return put_user(len, optlen);
1126 	}
1127 	case IP_FREEBIND:
1128 		val = inet->freebind;
1129 		break;
1130 	default:
1131 		release_sock(sk);
1132 		return -ENOPROTOOPT;
1133 	}
1134 	release_sock(sk);
1135 
1136 	if (len < sizeof(int) && len > 0 && val>=0 && val<=255) {
1137 		unsigned char ucval = (unsigned char)val;
1138 		len = 1;
1139 		if (put_user(len, optlen))
1140 			return -EFAULT;
1141 		if (copy_to_user(optval,&ucval,1))
1142 			return -EFAULT;
1143 	} else {
1144 		len = min_t(unsigned int, sizeof(int), len);
1145 		if (put_user(len, optlen))
1146 			return -EFAULT;
1147 		if (copy_to_user(optval,&val,len))
1148 			return -EFAULT;
1149 	}
1150 	return 0;
1151 }
1152 
1153 int ip_getsockopt(struct sock *sk, int level,
1154 		  int optname, char __user *optval, int __user *optlen)
1155 {
1156 	int err;
1157 
1158 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1159 #ifdef CONFIG_NETFILTER
1160 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1161 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1162 			!ip_mroute_opt(optname)) {
1163 		int len;
1164 
1165 		if (get_user(len,optlen))
1166 			return -EFAULT;
1167 
1168 		lock_sock(sk);
1169 		err = nf_getsockopt(sk, PF_INET, optname, optval,
1170 				&len);
1171 		release_sock(sk);
1172 		if (err >= 0)
1173 			err = put_user(len, optlen);
1174 		return err;
1175 	}
1176 #endif
1177 	return err;
1178 }
1179 
1180 #ifdef CONFIG_COMPAT
1181 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1182 			 char __user *optval, int __user *optlen)
1183 {
1184 	int err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1185 #ifdef CONFIG_NETFILTER
1186 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1187 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1188 			!ip_mroute_opt(optname)) {
1189 		int len;
1190 
1191 		if (get_user(len, optlen))
1192 			return -EFAULT;
1193 
1194 		lock_sock(sk);
1195 		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1196 		release_sock(sk);
1197 		if (err >= 0)
1198 			err = put_user(len, optlen);
1199 		return err;
1200 	}
1201 #endif
1202 	return err;
1203 }
1204 
1205 EXPORT_SYMBOL(compat_ip_getsockopt);
1206 #endif
1207 
1208 EXPORT_SYMBOL(ip_cmsg_recv);
1209 
1210 EXPORT_SYMBOL(ip_getsockopt);
1211 EXPORT_SYMBOL(ip_setsockopt);
1212