xref: /openbmc/linux/net/ipv4/ip_sockglue.c (revision 8684014d)
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  * Authors:	see ip.c
9  *
10  * Fixes:
11  *		Many		:	Split from ip.c , see ip.c for history.
12  *		Martin Mares	:	TOS setting fixed.
13  *		Alan Cox	:	Fixed a couple of oopses in Martin's
14  *					TOS tweaks.
15  *		Mike McLagan	:	Routing by source
16  */
17 
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/mm.h>
21 #include <linux/skbuff.h>
22 #include <linux/ip.h>
23 #include <linux/icmp.h>
24 #include <linux/inetdevice.h>
25 #include <linux/netdevice.h>
26 #include <linux/slab.h>
27 #include <net/sock.h>
28 #include <net/ip.h>
29 #include <net/icmp.h>
30 #include <net/tcp_states.h>
31 #include <linux/udp.h>
32 #include <linux/igmp.h>
33 #include <linux/netfilter.h>
34 #include <linux/route.h>
35 #include <linux/mroute.h>
36 #include <net/inet_ecn.h>
37 #include <net/route.h>
38 #include <net/xfrm.h>
39 #include <net/compat.h>
40 #if IS_ENABLED(CONFIG_IPV6)
41 #include <net/transp_v6.h>
42 #endif
43 #include <net/ip_fib.h>
44 
45 #include <linux/errqueue.h>
46 #include <asm/uaccess.h>
47 
48 #define IP_CMSG_PKTINFO		1
49 #define IP_CMSG_TTL		2
50 #define IP_CMSG_TOS		4
51 #define IP_CMSG_RECVOPTS	8
52 #define IP_CMSG_RETOPTS		16
53 #define IP_CMSG_PASSSEC		32
54 #define IP_CMSG_ORIGDSTADDR     64
55 
56 /*
57  *	SOL_IP control messages.
58  */
59 
60 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
61 {
62 	struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
63 
64 	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
65 
66 	put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
67 }
68 
69 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
70 {
71 	int ttl = ip_hdr(skb)->ttl;
72 	put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
73 }
74 
75 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
76 {
77 	put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
78 }
79 
80 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
81 {
82 	if (IPCB(skb)->opt.optlen == 0)
83 		return;
84 
85 	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
86 		 ip_hdr(skb) + 1);
87 }
88 
89 
90 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
91 {
92 	unsigned char optbuf[sizeof(struct ip_options) + 40];
93 	struct ip_options *opt = (struct ip_options *)optbuf;
94 
95 	if (IPCB(skb)->opt.optlen == 0)
96 		return;
97 
98 	if (ip_options_echo(opt, skb)) {
99 		msg->msg_flags |= MSG_CTRUNC;
100 		return;
101 	}
102 	ip_options_undo(opt);
103 
104 	put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
105 }
106 
107 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
108 {
109 	char *secdata;
110 	u32 seclen, secid;
111 	int err;
112 
113 	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
114 	if (err)
115 		return;
116 
117 	err = security_secid_to_secctx(secid, &secdata, &seclen);
118 	if (err)
119 		return;
120 
121 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
122 	security_release_secctx(secdata, seclen);
123 }
124 
125 static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
126 {
127 	struct sockaddr_in sin;
128 	const struct iphdr *iph = ip_hdr(skb);
129 	__be16 *ports = (__be16 *)skb_transport_header(skb);
130 
131 	if (skb_transport_offset(skb) + 4 > skb->len)
132 		return;
133 
134 	/* All current transport protocols have the port numbers in the
135 	 * first four bytes of the transport header and this function is
136 	 * written with this assumption in mind.
137 	 */
138 
139 	sin.sin_family = AF_INET;
140 	sin.sin_addr.s_addr = iph->daddr;
141 	sin.sin_port = ports[1];
142 	memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
143 
144 	put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
145 }
146 
147 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
148 {
149 	struct inet_sock *inet = inet_sk(skb->sk);
150 	unsigned int flags = inet->cmsg_flags;
151 
152 	/* Ordered by supposed usage frequency */
153 	if (flags & 1)
154 		ip_cmsg_recv_pktinfo(msg, skb);
155 	if ((flags >>= 1) == 0)
156 		return;
157 
158 	if (flags & 1)
159 		ip_cmsg_recv_ttl(msg, skb);
160 	if ((flags >>= 1) == 0)
161 		return;
162 
163 	if (flags & 1)
164 		ip_cmsg_recv_tos(msg, skb);
165 	if ((flags >>= 1) == 0)
166 		return;
167 
168 	if (flags & 1)
169 		ip_cmsg_recv_opts(msg, skb);
170 	if ((flags >>= 1) == 0)
171 		return;
172 
173 	if (flags & 1)
174 		ip_cmsg_recv_retopts(msg, skb);
175 	if ((flags >>= 1) == 0)
176 		return;
177 
178 	if (flags & 1)
179 		ip_cmsg_recv_security(msg, skb);
180 
181 	if ((flags >>= 1) == 0)
182 		return;
183 	if (flags & 1)
184 		ip_cmsg_recv_dstaddr(msg, skb);
185 
186 }
187 EXPORT_SYMBOL(ip_cmsg_recv);
188 
189 int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc,
190 		 bool allow_ipv6)
191 {
192 	int err, val;
193 	struct cmsghdr *cmsg;
194 
195 	for_each_cmsghdr(cmsg, msg) {
196 		if (!CMSG_OK(msg, cmsg))
197 			return -EINVAL;
198 #if IS_ENABLED(CONFIG_IPV6)
199 		if (allow_ipv6 &&
200 		    cmsg->cmsg_level == SOL_IPV6 &&
201 		    cmsg->cmsg_type == IPV6_PKTINFO) {
202 			struct in6_pktinfo *src_info;
203 
204 			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info)))
205 				return -EINVAL;
206 			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
207 			if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
208 				return -EINVAL;
209 			ipc->oif = src_info->ipi6_ifindex;
210 			ipc->addr = src_info->ipi6_addr.s6_addr32[3];
211 			continue;
212 		}
213 #endif
214 		if (cmsg->cmsg_level != SOL_IP)
215 			continue;
216 		switch (cmsg->cmsg_type) {
217 		case IP_RETOPTS:
218 			err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
219 			err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg),
220 					     err < 40 ? err : 40);
221 			if (err)
222 				return err;
223 			break;
224 		case IP_PKTINFO:
225 		{
226 			struct in_pktinfo *info;
227 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
228 				return -EINVAL;
229 			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
230 			ipc->oif = info->ipi_ifindex;
231 			ipc->addr = info->ipi_spec_dst.s_addr;
232 			break;
233 		}
234 		case IP_TTL:
235 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
236 				return -EINVAL;
237 			val = *(int *)CMSG_DATA(cmsg);
238 			if (val < 1 || val > 255)
239 				return -EINVAL;
240 			ipc->ttl = val;
241 			break;
242 		case IP_TOS:
243 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
244 				return -EINVAL;
245 			val = *(int *)CMSG_DATA(cmsg);
246 			if (val < 0 || val > 255)
247 				return -EINVAL;
248 			ipc->tos = val;
249 			ipc->priority = rt_tos2priority(ipc->tos);
250 			break;
251 
252 		default:
253 			return -EINVAL;
254 		}
255 	}
256 	return 0;
257 }
258 
259 
260 /* Special input handler for packets caught by router alert option.
261    They are selected only by protocol field, and then processed likely
262    local ones; but only if someone wants them! Otherwise, router
263    not running rsvpd will kill RSVP.
264 
265    It is user level problem, what it will make with them.
266    I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
267    but receiver should be enough clever f.e. to forward mtrace requests,
268    sent to multicast group to reach destination designated router.
269  */
270 struct ip_ra_chain __rcu *ip_ra_chain;
271 static DEFINE_SPINLOCK(ip_ra_lock);
272 
273 
274 static void ip_ra_destroy_rcu(struct rcu_head *head)
275 {
276 	struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
277 
278 	sock_put(ra->saved_sk);
279 	kfree(ra);
280 }
281 
282 int ip_ra_control(struct sock *sk, unsigned char on,
283 		  void (*destructor)(struct sock *))
284 {
285 	struct ip_ra_chain *ra, *new_ra;
286 	struct ip_ra_chain __rcu **rap;
287 
288 	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
289 		return -EINVAL;
290 
291 	new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
292 
293 	spin_lock_bh(&ip_ra_lock);
294 	for (rap = &ip_ra_chain;
295 	     (ra = rcu_dereference_protected(*rap,
296 			lockdep_is_held(&ip_ra_lock))) != NULL;
297 	     rap = &ra->next) {
298 		if (ra->sk == sk) {
299 			if (on) {
300 				spin_unlock_bh(&ip_ra_lock);
301 				kfree(new_ra);
302 				return -EADDRINUSE;
303 			}
304 			/* dont let ip_call_ra_chain() use sk again */
305 			ra->sk = NULL;
306 			RCU_INIT_POINTER(*rap, ra->next);
307 			spin_unlock_bh(&ip_ra_lock);
308 
309 			if (ra->destructor)
310 				ra->destructor(sk);
311 			/*
312 			 * Delay sock_put(sk) and kfree(ra) after one rcu grace
313 			 * period. This guarantee ip_call_ra_chain() dont need
314 			 * to mess with socket refcounts.
315 			 */
316 			ra->saved_sk = sk;
317 			call_rcu(&ra->rcu, ip_ra_destroy_rcu);
318 			return 0;
319 		}
320 	}
321 	if (new_ra == NULL) {
322 		spin_unlock_bh(&ip_ra_lock);
323 		return -ENOBUFS;
324 	}
325 	new_ra->sk = sk;
326 	new_ra->destructor = destructor;
327 
328 	RCU_INIT_POINTER(new_ra->next, ra);
329 	rcu_assign_pointer(*rap, new_ra);
330 	sock_hold(sk);
331 	spin_unlock_bh(&ip_ra_lock);
332 
333 	return 0;
334 }
335 
336 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
337 		   __be16 port, u32 info, u8 *payload)
338 {
339 	struct sock_exterr_skb *serr;
340 
341 	skb = skb_clone(skb, GFP_ATOMIC);
342 	if (!skb)
343 		return;
344 
345 	serr = SKB_EXT_ERR(skb);
346 	serr->ee.ee_errno = err;
347 	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
348 	serr->ee.ee_type = icmp_hdr(skb)->type;
349 	serr->ee.ee_code = icmp_hdr(skb)->code;
350 	serr->ee.ee_pad = 0;
351 	serr->ee.ee_info = info;
352 	serr->ee.ee_data = 0;
353 	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
354 				   skb_network_header(skb);
355 	serr->port = port;
356 
357 	if (skb_pull(skb, payload - skb->data) != NULL) {
358 		skb_reset_transport_header(skb);
359 		if (sock_queue_err_skb(sk, skb) == 0)
360 			return;
361 	}
362 	kfree_skb(skb);
363 }
364 
365 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
366 {
367 	struct inet_sock *inet = inet_sk(sk);
368 	struct sock_exterr_skb *serr;
369 	struct iphdr *iph;
370 	struct sk_buff *skb;
371 
372 	if (!inet->recverr)
373 		return;
374 
375 	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
376 	if (!skb)
377 		return;
378 
379 	skb_put(skb, sizeof(struct iphdr));
380 	skb_reset_network_header(skb);
381 	iph = ip_hdr(skb);
382 	iph->daddr = daddr;
383 
384 	serr = SKB_EXT_ERR(skb);
385 	serr->ee.ee_errno = err;
386 	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
387 	serr->ee.ee_type = 0;
388 	serr->ee.ee_code = 0;
389 	serr->ee.ee_pad = 0;
390 	serr->ee.ee_info = info;
391 	serr->ee.ee_data = 0;
392 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
393 	serr->port = port;
394 
395 	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
396 	skb_reset_transport_header(skb);
397 
398 	if (sock_queue_err_skb(sk, skb))
399 		kfree_skb(skb);
400 }
401 
402 static bool ipv4_pktinfo_prepare_errqueue(const struct sock *sk,
403 					  const struct sk_buff *skb,
404 					  int ee_origin)
405 {
406 	struct in_pktinfo *info = PKTINFO_SKB_CB(skb);
407 
408 	if ((ee_origin != SO_EE_ORIGIN_TIMESTAMPING) ||
409 	    (!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_CMSG)) ||
410 	    (!skb->dev))
411 		return false;
412 
413 	info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr;
414 	info->ipi_ifindex = skb->dev->ifindex;
415 	return true;
416 }
417 
418 /*
419  *	Handle MSG_ERRQUEUE
420  */
421 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
422 {
423 	struct sock_exterr_skb *serr;
424 	struct sk_buff *skb;
425 	DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
426 	struct {
427 		struct sock_extended_err ee;
428 		struct sockaddr_in	 offender;
429 	} errhdr;
430 	int err;
431 	int copied;
432 
433 	WARN_ON_ONCE(sk->sk_family == AF_INET6);
434 
435 	err = -EAGAIN;
436 	skb = sock_dequeue_err_skb(sk);
437 	if (skb == NULL)
438 		goto out;
439 
440 	copied = skb->len;
441 	if (copied > len) {
442 		msg->msg_flags |= MSG_TRUNC;
443 		copied = len;
444 	}
445 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
446 	if (err)
447 		goto out_free_skb;
448 
449 	sock_recv_timestamp(msg, sk, skb);
450 
451 	serr = SKB_EXT_ERR(skb);
452 
453 	if (sin) {
454 		sin->sin_family = AF_INET;
455 		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
456 						   serr->addr_offset);
457 		sin->sin_port = serr->port;
458 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
459 		*addr_len = sizeof(*sin);
460 	}
461 
462 	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
463 	sin = &errhdr.offender;
464 	sin->sin_family = AF_UNSPEC;
465 
466 	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
467 	    ipv4_pktinfo_prepare_errqueue(sk, skb, serr->ee.ee_origin)) {
468 		struct inet_sock *inet = inet_sk(sk);
469 
470 		sin->sin_family = AF_INET;
471 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
472 		sin->sin_port = 0;
473 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
474 		if (inet->cmsg_flags)
475 			ip_cmsg_recv(msg, skb);
476 	}
477 
478 	put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
479 
480 	/* Now we could try to dump offended packet options */
481 
482 	msg->msg_flags |= MSG_ERRQUEUE;
483 	err = copied;
484 
485 out_free_skb:
486 	kfree_skb(skb);
487 out:
488 	return err;
489 }
490 
491 
492 /*
493  *	Socket option code for IP. This is the end of the line after any
494  *	TCP,UDP etc options on an IP socket.
495  */
496 
497 static int do_ip_setsockopt(struct sock *sk, int level,
498 			    int optname, char __user *optval, unsigned int optlen)
499 {
500 	struct inet_sock *inet = inet_sk(sk);
501 	int val = 0, err;
502 
503 	switch (optname) {
504 	case IP_PKTINFO:
505 	case IP_RECVTTL:
506 	case IP_RECVOPTS:
507 	case IP_RECVTOS:
508 	case IP_RETOPTS:
509 	case IP_TOS:
510 	case IP_TTL:
511 	case IP_HDRINCL:
512 	case IP_MTU_DISCOVER:
513 	case IP_RECVERR:
514 	case IP_ROUTER_ALERT:
515 	case IP_FREEBIND:
516 	case IP_PASSSEC:
517 	case IP_TRANSPARENT:
518 	case IP_MINTTL:
519 	case IP_NODEFRAG:
520 	case IP_UNICAST_IF:
521 	case IP_MULTICAST_TTL:
522 	case IP_MULTICAST_ALL:
523 	case IP_MULTICAST_LOOP:
524 	case IP_RECVORIGDSTADDR:
525 		if (optlen >= sizeof(int)) {
526 			if (get_user(val, (int __user *) optval))
527 				return -EFAULT;
528 		} else if (optlen >= sizeof(char)) {
529 			unsigned char ucval;
530 
531 			if (get_user(ucval, (unsigned char __user *) optval))
532 				return -EFAULT;
533 			val = (int) ucval;
534 		}
535 	}
536 
537 	/* If optlen==0, it is equivalent to val == 0 */
538 
539 	if (ip_mroute_opt(optname))
540 		return ip_mroute_setsockopt(sk, optname, optval, optlen);
541 
542 	err = 0;
543 	lock_sock(sk);
544 
545 	switch (optname) {
546 	case IP_OPTIONS:
547 	{
548 		struct ip_options_rcu *old, *opt = NULL;
549 
550 		if (optlen > 40)
551 			goto e_inval;
552 		err = ip_options_get_from_user(sock_net(sk), &opt,
553 					       optval, optlen);
554 		if (err)
555 			break;
556 		old = rcu_dereference_protected(inet->inet_opt,
557 						sock_owned_by_user(sk));
558 		if (inet->is_icsk) {
559 			struct inet_connection_sock *icsk = inet_csk(sk);
560 #if IS_ENABLED(CONFIG_IPV6)
561 			if (sk->sk_family == PF_INET ||
562 			    (!((1 << sk->sk_state) &
563 			       (TCPF_LISTEN | TCPF_CLOSE)) &&
564 			     inet->inet_daddr != LOOPBACK4_IPV6)) {
565 #endif
566 				if (old)
567 					icsk->icsk_ext_hdr_len -= old->opt.optlen;
568 				if (opt)
569 					icsk->icsk_ext_hdr_len += opt->opt.optlen;
570 				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
571 #if IS_ENABLED(CONFIG_IPV6)
572 			}
573 #endif
574 		}
575 		rcu_assign_pointer(inet->inet_opt, opt);
576 		if (old)
577 			kfree_rcu(old, rcu);
578 		break;
579 	}
580 	case IP_PKTINFO:
581 		if (val)
582 			inet->cmsg_flags |= IP_CMSG_PKTINFO;
583 		else
584 			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
585 		break;
586 	case IP_RECVTTL:
587 		if (val)
588 			inet->cmsg_flags |=  IP_CMSG_TTL;
589 		else
590 			inet->cmsg_flags &= ~IP_CMSG_TTL;
591 		break;
592 	case IP_RECVTOS:
593 		if (val)
594 			inet->cmsg_flags |=  IP_CMSG_TOS;
595 		else
596 			inet->cmsg_flags &= ~IP_CMSG_TOS;
597 		break;
598 	case IP_RECVOPTS:
599 		if (val)
600 			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
601 		else
602 			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
603 		break;
604 	case IP_RETOPTS:
605 		if (val)
606 			inet->cmsg_flags |= IP_CMSG_RETOPTS;
607 		else
608 			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
609 		break;
610 	case IP_PASSSEC:
611 		if (val)
612 			inet->cmsg_flags |= IP_CMSG_PASSSEC;
613 		else
614 			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
615 		break;
616 	case IP_RECVORIGDSTADDR:
617 		if (val)
618 			inet->cmsg_flags |= IP_CMSG_ORIGDSTADDR;
619 		else
620 			inet->cmsg_flags &= ~IP_CMSG_ORIGDSTADDR;
621 		break;
622 	case IP_TOS:	/* This sets both TOS and Precedence */
623 		if (sk->sk_type == SOCK_STREAM) {
624 			val &= ~INET_ECN_MASK;
625 			val |= inet->tos & INET_ECN_MASK;
626 		}
627 		if (inet->tos != val) {
628 			inet->tos = val;
629 			sk->sk_priority = rt_tos2priority(val);
630 			sk_dst_reset(sk);
631 		}
632 		break;
633 	case IP_TTL:
634 		if (optlen < 1)
635 			goto e_inval;
636 		if (val != -1 && (val < 1 || val > 255))
637 			goto e_inval;
638 		inet->uc_ttl = val;
639 		break;
640 	case IP_HDRINCL:
641 		if (sk->sk_type != SOCK_RAW) {
642 			err = -ENOPROTOOPT;
643 			break;
644 		}
645 		inet->hdrincl = val ? 1 : 0;
646 		break;
647 	case IP_NODEFRAG:
648 		if (sk->sk_type != SOCK_RAW) {
649 			err = -ENOPROTOOPT;
650 			break;
651 		}
652 		inet->nodefrag = val ? 1 : 0;
653 		break;
654 	case IP_MTU_DISCOVER:
655 		if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
656 			goto e_inval;
657 		inet->pmtudisc = val;
658 		break;
659 	case IP_RECVERR:
660 		inet->recverr = !!val;
661 		if (!val)
662 			skb_queue_purge(&sk->sk_error_queue);
663 		break;
664 	case IP_MULTICAST_TTL:
665 		if (sk->sk_type == SOCK_STREAM)
666 			goto e_inval;
667 		if (optlen < 1)
668 			goto e_inval;
669 		if (val == -1)
670 			val = 1;
671 		if (val < 0 || val > 255)
672 			goto e_inval;
673 		inet->mc_ttl = val;
674 		break;
675 	case IP_MULTICAST_LOOP:
676 		if (optlen < 1)
677 			goto e_inval;
678 		inet->mc_loop = !!val;
679 		break;
680 	case IP_UNICAST_IF:
681 	{
682 		struct net_device *dev = NULL;
683 		int ifindex;
684 
685 		if (optlen != sizeof(int))
686 			goto e_inval;
687 
688 		ifindex = (__force int)ntohl((__force __be32)val);
689 		if (ifindex == 0) {
690 			inet->uc_index = 0;
691 			err = 0;
692 			break;
693 		}
694 
695 		dev = dev_get_by_index(sock_net(sk), ifindex);
696 		err = -EADDRNOTAVAIL;
697 		if (!dev)
698 			break;
699 		dev_put(dev);
700 
701 		err = -EINVAL;
702 		if (sk->sk_bound_dev_if)
703 			break;
704 
705 		inet->uc_index = ifindex;
706 		err = 0;
707 		break;
708 	}
709 	case IP_MULTICAST_IF:
710 	{
711 		struct ip_mreqn mreq;
712 		struct net_device *dev = NULL;
713 
714 		if (sk->sk_type == SOCK_STREAM)
715 			goto e_inval;
716 		/*
717 		 *	Check the arguments are allowable
718 		 */
719 
720 		if (optlen < sizeof(struct in_addr))
721 			goto e_inval;
722 
723 		err = -EFAULT;
724 		if (optlen >= sizeof(struct ip_mreqn)) {
725 			if (copy_from_user(&mreq, optval, sizeof(mreq)))
726 				break;
727 		} else {
728 			memset(&mreq, 0, sizeof(mreq));
729 			if (optlen >= sizeof(struct ip_mreq)) {
730 				if (copy_from_user(&mreq, optval,
731 						   sizeof(struct ip_mreq)))
732 					break;
733 			} else if (optlen >= sizeof(struct in_addr)) {
734 				if (copy_from_user(&mreq.imr_address, optval,
735 						   sizeof(struct in_addr)))
736 					break;
737 			}
738 		}
739 
740 		if (!mreq.imr_ifindex) {
741 			if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
742 				inet->mc_index = 0;
743 				inet->mc_addr  = 0;
744 				err = 0;
745 				break;
746 			}
747 			dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
748 			if (dev)
749 				mreq.imr_ifindex = dev->ifindex;
750 		} else
751 			dev = dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
752 
753 
754 		err = -EADDRNOTAVAIL;
755 		if (!dev)
756 			break;
757 		dev_put(dev);
758 
759 		err = -EINVAL;
760 		if (sk->sk_bound_dev_if &&
761 		    mreq.imr_ifindex != sk->sk_bound_dev_if)
762 			break;
763 
764 		inet->mc_index = mreq.imr_ifindex;
765 		inet->mc_addr  = mreq.imr_address.s_addr;
766 		err = 0;
767 		break;
768 	}
769 
770 	case IP_ADD_MEMBERSHIP:
771 	case IP_DROP_MEMBERSHIP:
772 	{
773 		struct ip_mreqn mreq;
774 
775 		err = -EPROTO;
776 		if (inet_sk(sk)->is_icsk)
777 			break;
778 
779 		if (optlen < sizeof(struct ip_mreq))
780 			goto e_inval;
781 		err = -EFAULT;
782 		if (optlen >= sizeof(struct ip_mreqn)) {
783 			if (copy_from_user(&mreq, optval, sizeof(mreq)))
784 				break;
785 		} else {
786 			memset(&mreq, 0, sizeof(mreq));
787 			if (copy_from_user(&mreq, optval, sizeof(struct ip_mreq)))
788 				break;
789 		}
790 
791 		if (optname == IP_ADD_MEMBERSHIP)
792 			err = ip_mc_join_group(sk, &mreq);
793 		else
794 			err = ip_mc_leave_group(sk, &mreq);
795 		break;
796 	}
797 	case IP_MSFILTER:
798 	{
799 		struct ip_msfilter *msf;
800 
801 		if (optlen < IP_MSFILTER_SIZE(0))
802 			goto e_inval;
803 		if (optlen > sysctl_optmem_max) {
804 			err = -ENOBUFS;
805 			break;
806 		}
807 		msf = kmalloc(optlen, GFP_KERNEL);
808 		if (!msf) {
809 			err = -ENOBUFS;
810 			break;
811 		}
812 		err = -EFAULT;
813 		if (copy_from_user(msf, optval, optlen)) {
814 			kfree(msf);
815 			break;
816 		}
817 		/* numsrc >= (1G-4) overflow in 32 bits */
818 		if (msf->imsf_numsrc >= 0x3ffffffcU ||
819 		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
820 			kfree(msf);
821 			err = -ENOBUFS;
822 			break;
823 		}
824 		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
825 			kfree(msf);
826 			err = -EINVAL;
827 			break;
828 		}
829 		err = ip_mc_msfilter(sk, msf, 0);
830 		kfree(msf);
831 		break;
832 	}
833 	case IP_BLOCK_SOURCE:
834 	case IP_UNBLOCK_SOURCE:
835 	case IP_ADD_SOURCE_MEMBERSHIP:
836 	case IP_DROP_SOURCE_MEMBERSHIP:
837 	{
838 		struct ip_mreq_source mreqs;
839 		int omode, add;
840 
841 		if (optlen != sizeof(struct ip_mreq_source))
842 			goto e_inval;
843 		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
844 			err = -EFAULT;
845 			break;
846 		}
847 		if (optname == IP_BLOCK_SOURCE) {
848 			omode = MCAST_EXCLUDE;
849 			add = 1;
850 		} else if (optname == IP_UNBLOCK_SOURCE) {
851 			omode = MCAST_EXCLUDE;
852 			add = 0;
853 		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
854 			struct ip_mreqn mreq;
855 
856 			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
857 			mreq.imr_address.s_addr = mreqs.imr_interface;
858 			mreq.imr_ifindex = 0;
859 			err = ip_mc_join_group(sk, &mreq);
860 			if (err && err != -EADDRINUSE)
861 				break;
862 			omode = MCAST_INCLUDE;
863 			add = 1;
864 		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
865 			omode = MCAST_INCLUDE;
866 			add = 0;
867 		}
868 		err = ip_mc_source(add, omode, sk, &mreqs, 0);
869 		break;
870 	}
871 	case MCAST_JOIN_GROUP:
872 	case MCAST_LEAVE_GROUP:
873 	{
874 		struct group_req greq;
875 		struct sockaddr_in *psin;
876 		struct ip_mreqn mreq;
877 
878 		if (optlen < sizeof(struct group_req))
879 			goto e_inval;
880 		err = -EFAULT;
881 		if (copy_from_user(&greq, optval, sizeof(greq)))
882 			break;
883 		psin = (struct sockaddr_in *)&greq.gr_group;
884 		if (psin->sin_family != AF_INET)
885 			goto e_inval;
886 		memset(&mreq, 0, sizeof(mreq));
887 		mreq.imr_multiaddr = psin->sin_addr;
888 		mreq.imr_ifindex = greq.gr_interface;
889 
890 		if (optname == MCAST_JOIN_GROUP)
891 			err = ip_mc_join_group(sk, &mreq);
892 		else
893 			err = ip_mc_leave_group(sk, &mreq);
894 		break;
895 	}
896 	case MCAST_JOIN_SOURCE_GROUP:
897 	case MCAST_LEAVE_SOURCE_GROUP:
898 	case MCAST_BLOCK_SOURCE:
899 	case MCAST_UNBLOCK_SOURCE:
900 	{
901 		struct group_source_req greqs;
902 		struct ip_mreq_source mreqs;
903 		struct sockaddr_in *psin;
904 		int omode, add;
905 
906 		if (optlen != sizeof(struct group_source_req))
907 			goto e_inval;
908 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
909 			err = -EFAULT;
910 			break;
911 		}
912 		if (greqs.gsr_group.ss_family != AF_INET ||
913 		    greqs.gsr_source.ss_family != AF_INET) {
914 			err = -EADDRNOTAVAIL;
915 			break;
916 		}
917 		psin = (struct sockaddr_in *)&greqs.gsr_group;
918 		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
919 		psin = (struct sockaddr_in *)&greqs.gsr_source;
920 		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
921 		mreqs.imr_interface = 0; /* use index for mc_source */
922 
923 		if (optname == MCAST_BLOCK_SOURCE) {
924 			omode = MCAST_EXCLUDE;
925 			add = 1;
926 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
927 			omode = MCAST_EXCLUDE;
928 			add = 0;
929 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
930 			struct ip_mreqn mreq;
931 
932 			psin = (struct sockaddr_in *)&greqs.gsr_group;
933 			mreq.imr_multiaddr = psin->sin_addr;
934 			mreq.imr_address.s_addr = 0;
935 			mreq.imr_ifindex = greqs.gsr_interface;
936 			err = ip_mc_join_group(sk, &mreq);
937 			if (err && err != -EADDRINUSE)
938 				break;
939 			greqs.gsr_interface = mreq.imr_ifindex;
940 			omode = MCAST_INCLUDE;
941 			add = 1;
942 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
943 			omode = MCAST_INCLUDE;
944 			add = 0;
945 		}
946 		err = ip_mc_source(add, omode, sk, &mreqs,
947 				   greqs.gsr_interface);
948 		break;
949 	}
950 	case MCAST_MSFILTER:
951 	{
952 		struct sockaddr_in *psin;
953 		struct ip_msfilter *msf = NULL;
954 		struct group_filter *gsf = NULL;
955 		int msize, i, ifindex;
956 
957 		if (optlen < GROUP_FILTER_SIZE(0))
958 			goto e_inval;
959 		if (optlen > sysctl_optmem_max) {
960 			err = -ENOBUFS;
961 			break;
962 		}
963 		gsf = kmalloc(optlen, GFP_KERNEL);
964 		if (!gsf) {
965 			err = -ENOBUFS;
966 			break;
967 		}
968 		err = -EFAULT;
969 		if (copy_from_user(gsf, optval, optlen))
970 			goto mc_msf_out;
971 
972 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
973 		if (gsf->gf_numsrc >= 0x1ffffff ||
974 		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
975 			err = -ENOBUFS;
976 			goto mc_msf_out;
977 		}
978 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
979 			err = -EINVAL;
980 			goto mc_msf_out;
981 		}
982 		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
983 		msf = kmalloc(msize, GFP_KERNEL);
984 		if (!msf) {
985 			err = -ENOBUFS;
986 			goto mc_msf_out;
987 		}
988 		ifindex = gsf->gf_interface;
989 		psin = (struct sockaddr_in *)&gsf->gf_group;
990 		if (psin->sin_family != AF_INET) {
991 			err = -EADDRNOTAVAIL;
992 			goto mc_msf_out;
993 		}
994 		msf->imsf_multiaddr = psin->sin_addr.s_addr;
995 		msf->imsf_interface = 0;
996 		msf->imsf_fmode = gsf->gf_fmode;
997 		msf->imsf_numsrc = gsf->gf_numsrc;
998 		err = -EADDRNOTAVAIL;
999 		for (i = 0; i < gsf->gf_numsrc; ++i) {
1000 			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
1001 
1002 			if (psin->sin_family != AF_INET)
1003 				goto mc_msf_out;
1004 			msf->imsf_slist[i] = psin->sin_addr.s_addr;
1005 		}
1006 		kfree(gsf);
1007 		gsf = NULL;
1008 
1009 		err = ip_mc_msfilter(sk, msf, ifindex);
1010 mc_msf_out:
1011 		kfree(msf);
1012 		kfree(gsf);
1013 		break;
1014 	}
1015 	case IP_MULTICAST_ALL:
1016 		if (optlen < 1)
1017 			goto e_inval;
1018 		if (val != 0 && val != 1)
1019 			goto e_inval;
1020 		inet->mc_all = val;
1021 		break;
1022 	case IP_ROUTER_ALERT:
1023 		err = ip_ra_control(sk, val ? 1 : 0, NULL);
1024 		break;
1025 
1026 	case IP_FREEBIND:
1027 		if (optlen < 1)
1028 			goto e_inval;
1029 		inet->freebind = !!val;
1030 		break;
1031 
1032 	case IP_IPSEC_POLICY:
1033 	case IP_XFRM_POLICY:
1034 		err = -EPERM;
1035 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1036 			break;
1037 		err = xfrm_user_policy(sk, optname, optval, optlen);
1038 		break;
1039 
1040 	case IP_TRANSPARENT:
1041 		if (!!val && !ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1042 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1043 			err = -EPERM;
1044 			break;
1045 		}
1046 		if (optlen < 1)
1047 			goto e_inval;
1048 		inet->transparent = !!val;
1049 		break;
1050 
1051 	case IP_MINTTL:
1052 		if (optlen < 1)
1053 			goto e_inval;
1054 		if (val < 0 || val > 255)
1055 			goto e_inval;
1056 		inet->min_ttl = val;
1057 		break;
1058 
1059 	default:
1060 		err = -ENOPROTOOPT;
1061 		break;
1062 	}
1063 	release_sock(sk);
1064 	return err;
1065 
1066 e_inval:
1067 	release_sock(sk);
1068 	return -EINVAL;
1069 }
1070 
1071 /**
1072  * ipv4_pktinfo_prepare - transfer some info from rtable to skb
1073  * @sk: socket
1074  * @skb: buffer
1075  *
1076  * To support IP_CMSG_PKTINFO option, we store rt_iif and specific
1077  * destination in skb->cb[] before dst drop.
1078  * This way, receiver doesn't make cache line misses to read rtable.
1079  */
1080 void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)
1081 {
1082 	struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);
1083 	bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) ||
1084 		       ipv6_sk_rxinfo(sk);
1085 
1086 	if (prepare && skb_rtable(skb)) {
1087 		pktinfo->ipi_ifindex = inet_iif(skb);
1088 		pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);
1089 	} else {
1090 		pktinfo->ipi_ifindex = 0;
1091 		pktinfo->ipi_spec_dst.s_addr = 0;
1092 	}
1093 	skb_dst_drop(skb);
1094 }
1095 
1096 int ip_setsockopt(struct sock *sk, int level,
1097 		int optname, char __user *optval, unsigned int optlen)
1098 {
1099 	int err;
1100 
1101 	if (level != SOL_IP)
1102 		return -ENOPROTOOPT;
1103 
1104 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1105 #ifdef CONFIG_NETFILTER
1106 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1107 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1108 			optname != IP_IPSEC_POLICY &&
1109 			optname != IP_XFRM_POLICY &&
1110 			!ip_mroute_opt(optname)) {
1111 		lock_sock(sk);
1112 		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
1113 		release_sock(sk);
1114 	}
1115 #endif
1116 	return err;
1117 }
1118 EXPORT_SYMBOL(ip_setsockopt);
1119 
1120 #ifdef CONFIG_COMPAT
1121 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
1122 			 char __user *optval, unsigned int optlen)
1123 {
1124 	int err;
1125 
1126 	if (level != SOL_IP)
1127 		return -ENOPROTOOPT;
1128 
1129 	if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
1130 		return compat_mc_setsockopt(sk, level, optname, optval, optlen,
1131 			ip_setsockopt);
1132 
1133 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
1134 #ifdef CONFIG_NETFILTER
1135 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1136 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
1137 			optname != IP_IPSEC_POLICY &&
1138 			optname != IP_XFRM_POLICY &&
1139 			!ip_mroute_opt(optname)) {
1140 		lock_sock(sk);
1141 		err = compat_nf_setsockopt(sk, PF_INET, optname,
1142 					   optval, optlen);
1143 		release_sock(sk);
1144 	}
1145 #endif
1146 	return err;
1147 }
1148 EXPORT_SYMBOL(compat_ip_setsockopt);
1149 #endif
1150 
1151 /*
1152  *	Get the options. Note for future reference. The GET of IP options gets
1153  *	the _received_ ones. The set sets the _sent_ ones.
1154  */
1155 
1156 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
1157 			    char __user *optval, int __user *optlen, unsigned int flags)
1158 {
1159 	struct inet_sock *inet = inet_sk(sk);
1160 	int val;
1161 	int len;
1162 
1163 	if (level != SOL_IP)
1164 		return -EOPNOTSUPP;
1165 
1166 	if (ip_mroute_opt(optname))
1167 		return ip_mroute_getsockopt(sk, optname, optval, optlen);
1168 
1169 	if (get_user(len, optlen))
1170 		return -EFAULT;
1171 	if (len < 0)
1172 		return -EINVAL;
1173 
1174 	lock_sock(sk);
1175 
1176 	switch (optname) {
1177 	case IP_OPTIONS:
1178 	{
1179 		unsigned char optbuf[sizeof(struct ip_options)+40];
1180 		struct ip_options *opt = (struct ip_options *)optbuf;
1181 		struct ip_options_rcu *inet_opt;
1182 
1183 		inet_opt = rcu_dereference_protected(inet->inet_opt,
1184 						     sock_owned_by_user(sk));
1185 		opt->optlen = 0;
1186 		if (inet_opt)
1187 			memcpy(optbuf, &inet_opt->opt,
1188 			       sizeof(struct ip_options) +
1189 			       inet_opt->opt.optlen);
1190 		release_sock(sk);
1191 
1192 		if (opt->optlen == 0)
1193 			return put_user(0, optlen);
1194 
1195 		ip_options_undo(opt);
1196 
1197 		len = min_t(unsigned int, len, opt->optlen);
1198 		if (put_user(len, optlen))
1199 			return -EFAULT;
1200 		if (copy_to_user(optval, opt->__data, len))
1201 			return -EFAULT;
1202 		return 0;
1203 	}
1204 	case IP_PKTINFO:
1205 		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
1206 		break;
1207 	case IP_RECVTTL:
1208 		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1209 		break;
1210 	case IP_RECVTOS:
1211 		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1212 		break;
1213 	case IP_RECVOPTS:
1214 		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1215 		break;
1216 	case IP_RETOPTS:
1217 		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1218 		break;
1219 	case IP_PASSSEC:
1220 		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1221 		break;
1222 	case IP_RECVORIGDSTADDR:
1223 		val = (inet->cmsg_flags & IP_CMSG_ORIGDSTADDR) != 0;
1224 		break;
1225 	case IP_TOS:
1226 		val = inet->tos;
1227 		break;
1228 	case IP_TTL:
1229 		val = (inet->uc_ttl == -1 ?
1230 		       sysctl_ip_default_ttl :
1231 		       inet->uc_ttl);
1232 		break;
1233 	case IP_HDRINCL:
1234 		val = inet->hdrincl;
1235 		break;
1236 	case IP_NODEFRAG:
1237 		val = inet->nodefrag;
1238 		break;
1239 	case IP_MTU_DISCOVER:
1240 		val = inet->pmtudisc;
1241 		break;
1242 	case IP_MTU:
1243 	{
1244 		struct dst_entry *dst;
1245 		val = 0;
1246 		dst = sk_dst_get(sk);
1247 		if (dst) {
1248 			val = dst_mtu(dst);
1249 			dst_release(dst);
1250 		}
1251 		if (!val) {
1252 			release_sock(sk);
1253 			return -ENOTCONN;
1254 		}
1255 		break;
1256 	}
1257 	case IP_RECVERR:
1258 		val = inet->recverr;
1259 		break;
1260 	case IP_MULTICAST_TTL:
1261 		val = inet->mc_ttl;
1262 		break;
1263 	case IP_MULTICAST_LOOP:
1264 		val = inet->mc_loop;
1265 		break;
1266 	case IP_UNICAST_IF:
1267 		val = (__force int)htonl((__u32) inet->uc_index);
1268 		break;
1269 	case IP_MULTICAST_IF:
1270 	{
1271 		struct in_addr addr;
1272 		len = min_t(unsigned int, len, sizeof(struct in_addr));
1273 		addr.s_addr = inet->mc_addr;
1274 		release_sock(sk);
1275 
1276 		if (put_user(len, optlen))
1277 			return -EFAULT;
1278 		if (copy_to_user(optval, &addr, len))
1279 			return -EFAULT;
1280 		return 0;
1281 	}
1282 	case IP_MSFILTER:
1283 	{
1284 		struct ip_msfilter msf;
1285 		int err;
1286 
1287 		if (len < IP_MSFILTER_SIZE(0)) {
1288 			release_sock(sk);
1289 			return -EINVAL;
1290 		}
1291 		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1292 			release_sock(sk);
1293 			return -EFAULT;
1294 		}
1295 		err = ip_mc_msfget(sk, &msf,
1296 				   (struct ip_msfilter __user *)optval, optlen);
1297 		release_sock(sk);
1298 		return err;
1299 	}
1300 	case MCAST_MSFILTER:
1301 	{
1302 		struct group_filter gsf;
1303 		int err;
1304 
1305 		if (len < GROUP_FILTER_SIZE(0)) {
1306 			release_sock(sk);
1307 			return -EINVAL;
1308 		}
1309 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1310 			release_sock(sk);
1311 			return -EFAULT;
1312 		}
1313 		err = ip_mc_gsfget(sk, &gsf,
1314 				   (struct group_filter __user *)optval,
1315 				   optlen);
1316 		release_sock(sk);
1317 		return err;
1318 	}
1319 	case IP_MULTICAST_ALL:
1320 		val = inet->mc_all;
1321 		break;
1322 	case IP_PKTOPTIONS:
1323 	{
1324 		struct msghdr msg;
1325 
1326 		release_sock(sk);
1327 
1328 		if (sk->sk_type != SOCK_STREAM)
1329 			return -ENOPROTOOPT;
1330 
1331 		msg.msg_control = (__force void *) optval;
1332 		msg.msg_controllen = len;
1333 		msg.msg_flags = flags;
1334 
1335 		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1336 			struct in_pktinfo info;
1337 
1338 			info.ipi_addr.s_addr = inet->inet_rcv_saddr;
1339 			info.ipi_spec_dst.s_addr = inet->inet_rcv_saddr;
1340 			info.ipi_ifindex = inet->mc_index;
1341 			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1342 		}
1343 		if (inet->cmsg_flags & IP_CMSG_TTL) {
1344 			int hlim = inet->mc_ttl;
1345 			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1346 		}
1347 		if (inet->cmsg_flags & IP_CMSG_TOS) {
1348 			int tos = inet->rcv_tos;
1349 			put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);
1350 		}
1351 		len -= msg.msg_controllen;
1352 		return put_user(len, optlen);
1353 	}
1354 	case IP_FREEBIND:
1355 		val = inet->freebind;
1356 		break;
1357 	case IP_TRANSPARENT:
1358 		val = inet->transparent;
1359 		break;
1360 	case IP_MINTTL:
1361 		val = inet->min_ttl;
1362 		break;
1363 	default:
1364 		release_sock(sk);
1365 		return -ENOPROTOOPT;
1366 	}
1367 	release_sock(sk);
1368 
1369 	if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1370 		unsigned char ucval = (unsigned char)val;
1371 		len = 1;
1372 		if (put_user(len, optlen))
1373 			return -EFAULT;
1374 		if (copy_to_user(optval, &ucval, 1))
1375 			return -EFAULT;
1376 	} else {
1377 		len = min_t(unsigned int, sizeof(int), len);
1378 		if (put_user(len, optlen))
1379 			return -EFAULT;
1380 		if (copy_to_user(optval, &val, len))
1381 			return -EFAULT;
1382 	}
1383 	return 0;
1384 }
1385 
1386 int ip_getsockopt(struct sock *sk, int level,
1387 		  int optname, char __user *optval, int __user *optlen)
1388 {
1389 	int err;
1390 
1391 	err = do_ip_getsockopt(sk, level, optname, optval, optlen, 0);
1392 #ifdef CONFIG_NETFILTER
1393 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1394 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1395 			!ip_mroute_opt(optname)) {
1396 		int len;
1397 
1398 		if (get_user(len, optlen))
1399 			return -EFAULT;
1400 
1401 		lock_sock(sk);
1402 		err = nf_getsockopt(sk, PF_INET, optname, optval,
1403 				&len);
1404 		release_sock(sk);
1405 		if (err >= 0)
1406 			err = put_user(len, optlen);
1407 		return err;
1408 	}
1409 #endif
1410 	return err;
1411 }
1412 EXPORT_SYMBOL(ip_getsockopt);
1413 
1414 #ifdef CONFIG_COMPAT
1415 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1416 			 char __user *optval, int __user *optlen)
1417 {
1418 	int err;
1419 
1420 	if (optname == MCAST_MSFILTER)
1421 		return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1422 			ip_getsockopt);
1423 
1424 	err = do_ip_getsockopt(sk, level, optname, optval, optlen,
1425 		MSG_CMSG_COMPAT);
1426 
1427 #ifdef CONFIG_NETFILTER
1428 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1429 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1430 			!ip_mroute_opt(optname)) {
1431 		int len;
1432 
1433 		if (get_user(len, optlen))
1434 			return -EFAULT;
1435 
1436 		lock_sock(sk);
1437 		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1438 		release_sock(sk);
1439 		if (err >= 0)
1440 			err = put_user(len, optlen);
1441 		return err;
1442 	}
1443 #endif
1444 	return err;
1445 }
1446 EXPORT_SYMBOL(compat_ip_getsockopt);
1447 #endif
1448