xref: /openbmc/linux/net/ipv4/raw.c (revision 75f25bd3)
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  *		RAW - implementation of IP "raw" sockets.
7  *
8  * Authors:	Ross Biro
9  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10  *
11  * Fixes:
12  *		Alan Cox	:	verify_area() fixed up
13  *		Alan Cox	:	ICMP error handling
14  *		Alan Cox	:	EMSGSIZE if you send too big a packet
15  *		Alan Cox	: 	Now uses generic datagrams and shared
16  *					skbuff library. No more peek crashes,
17  *					no more backlogs
18  *		Alan Cox	:	Checks sk->broadcast.
19  *		Alan Cox	:	Uses skb_free_datagram/skb_copy_datagram
20  *		Alan Cox	:	Raw passes ip options too
21  *		Alan Cox	:	Setsocketopt added
22  *		Alan Cox	:	Fixed error return for broadcasts
23  *		Alan Cox	:	Removed wake_up calls
24  *		Alan Cox	:	Use ttl/tos
25  *		Alan Cox	:	Cleaned up old debugging
26  *		Alan Cox	:	Use new kernel side addresses
27  *	Arnt Gulbrandsen	:	Fixed MSG_DONTROUTE in raw sockets.
28  *		Alan Cox	:	BSD style RAW socket demultiplexing.
29  *		Alan Cox	:	Beginnings of mrouted support.
30  *		Alan Cox	:	Added IP_HDRINCL option.
31  *		Alan Cox	:	Skip broadcast check if BSDism set.
32  *		David S. Miller	:	New socket lookup architecture.
33  *
34  *		This program is free software; you can redistribute it and/or
35  *		modify it under the terms of the GNU General Public License
36  *		as published by the Free Software Foundation; either version
37  *		2 of the License, or (at your option) any later version.
38  */
39 
40 #include <linux/types.h>
41 #include <linux/atomic.h>
42 #include <asm/byteorder.h>
43 #include <asm/current.h>
44 #include <asm/uaccess.h>
45 #include <asm/ioctls.h>
46 #include <linux/stddef.h>
47 #include <linux/slab.h>
48 #include <linux/errno.h>
49 #include <linux/aio.h>
50 #include <linux/kernel.h>
51 #include <linux/spinlock.h>
52 #include <linux/sockios.h>
53 #include <linux/socket.h>
54 #include <linux/in.h>
55 #include <linux/mroute.h>
56 #include <linux/netdevice.h>
57 #include <linux/in_route.h>
58 #include <linux/route.h>
59 #include <linux/skbuff.h>
60 #include <net/net_namespace.h>
61 #include <net/dst.h>
62 #include <net/sock.h>
63 #include <linux/ip.h>
64 #include <linux/net.h>
65 #include <net/ip.h>
66 #include <net/icmp.h>
67 #include <net/udp.h>
68 #include <net/raw.h>
69 #include <net/snmp.h>
70 #include <net/tcp_states.h>
71 #include <net/inet_common.h>
72 #include <net/checksum.h>
73 #include <net/xfrm.h>
74 #include <linux/rtnetlink.h>
75 #include <linux/proc_fs.h>
76 #include <linux/seq_file.h>
77 #include <linux/netfilter.h>
78 #include <linux/netfilter_ipv4.h>
79 #include <linux/compat.h>
80 
81 static struct raw_hashinfo raw_v4_hashinfo = {
82 	.lock = __RW_LOCK_UNLOCKED(raw_v4_hashinfo.lock),
83 };
84 
85 void raw_hash_sk(struct sock *sk)
86 {
87 	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
88 	struct hlist_head *head;
89 
90 	head = &h->ht[inet_sk(sk)->inet_num & (RAW_HTABLE_SIZE - 1)];
91 
92 	write_lock_bh(&h->lock);
93 	sk_add_node(sk, head);
94 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
95 	write_unlock_bh(&h->lock);
96 }
97 EXPORT_SYMBOL_GPL(raw_hash_sk);
98 
99 void raw_unhash_sk(struct sock *sk)
100 {
101 	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
102 
103 	write_lock_bh(&h->lock);
104 	if (sk_del_node_init(sk))
105 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
106 	write_unlock_bh(&h->lock);
107 }
108 EXPORT_SYMBOL_GPL(raw_unhash_sk);
109 
110 static struct sock *__raw_v4_lookup(struct net *net, struct sock *sk,
111 		unsigned short num, __be32 raddr, __be32 laddr, int dif)
112 {
113 	struct hlist_node *node;
114 
115 	sk_for_each_from(sk, node) {
116 		struct inet_sock *inet = inet_sk(sk);
117 
118 		if (net_eq(sock_net(sk), net) && inet->inet_num == num	&&
119 		    !(inet->inet_daddr && inet->inet_daddr != raddr) 	&&
120 		    !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) &&
121 		    !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
122 			goto found; /* gotcha */
123 	}
124 	sk = NULL;
125 found:
126 	return sk;
127 }
128 
129 /*
130  *	0 - deliver
131  *	1 - block
132  */
133 static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb)
134 {
135 	int type;
136 
137 	if (!pskb_may_pull(skb, sizeof(struct icmphdr)))
138 		return 1;
139 
140 	type = icmp_hdr(skb)->type;
141 	if (type < 32) {
142 		__u32 data = raw_sk(sk)->filter.data;
143 
144 		return ((1 << type) & data) != 0;
145 	}
146 
147 	/* Do not block unknown ICMP types */
148 	return 0;
149 }
150 
151 /* IP input processing comes here for RAW socket delivery.
152  * Caller owns SKB, so we must make clones.
153  *
154  * RFC 1122: SHOULD pass TOS value up to the transport layer.
155  * -> It does. And not only TOS, but all IP header.
156  */
157 static int raw_v4_input(struct sk_buff *skb, const struct iphdr *iph, int hash)
158 {
159 	struct sock *sk;
160 	struct hlist_head *head;
161 	int delivered = 0;
162 	struct net *net;
163 
164 	read_lock(&raw_v4_hashinfo.lock);
165 	head = &raw_v4_hashinfo.ht[hash];
166 	if (hlist_empty(head))
167 		goto out;
168 
169 	net = dev_net(skb->dev);
170 	sk = __raw_v4_lookup(net, __sk_head(head), iph->protocol,
171 			     iph->saddr, iph->daddr,
172 			     skb->dev->ifindex);
173 
174 	while (sk) {
175 		delivered = 1;
176 		if (iph->protocol != IPPROTO_ICMP || !icmp_filter(sk, skb)) {
177 			struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
178 
179 			/* Not releasing hash table! */
180 			if (clone)
181 				raw_rcv(sk, clone);
182 		}
183 		sk = __raw_v4_lookup(net, sk_next(sk), iph->protocol,
184 				     iph->saddr, iph->daddr,
185 				     skb->dev->ifindex);
186 	}
187 out:
188 	read_unlock(&raw_v4_hashinfo.lock);
189 	return delivered;
190 }
191 
192 int raw_local_deliver(struct sk_buff *skb, int protocol)
193 {
194 	int hash;
195 	struct sock *raw_sk;
196 
197 	hash = protocol & (RAW_HTABLE_SIZE - 1);
198 	raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]);
199 
200 	/* If there maybe a raw socket we must check - if not we
201 	 * don't care less
202 	 */
203 	if (raw_sk && !raw_v4_input(skb, ip_hdr(skb), hash))
204 		raw_sk = NULL;
205 
206 	return raw_sk != NULL;
207 
208 }
209 
210 static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info)
211 {
212 	struct inet_sock *inet = inet_sk(sk);
213 	const int type = icmp_hdr(skb)->type;
214 	const int code = icmp_hdr(skb)->code;
215 	int err = 0;
216 	int harderr = 0;
217 
218 	/* Report error on raw socket, if:
219 	   1. User requested ip_recverr.
220 	   2. Socket is connected (otherwise the error indication
221 	      is useless without ip_recverr and error is hard.
222 	 */
223 	if (!inet->recverr && sk->sk_state != TCP_ESTABLISHED)
224 		return;
225 
226 	switch (type) {
227 	default:
228 	case ICMP_TIME_EXCEEDED:
229 		err = EHOSTUNREACH;
230 		break;
231 	case ICMP_SOURCE_QUENCH:
232 		return;
233 	case ICMP_PARAMETERPROB:
234 		err = EPROTO;
235 		harderr = 1;
236 		break;
237 	case ICMP_DEST_UNREACH:
238 		err = EHOSTUNREACH;
239 		if (code > NR_ICMP_UNREACH)
240 			break;
241 		err = icmp_err_convert[code].errno;
242 		harderr = icmp_err_convert[code].fatal;
243 		if (code == ICMP_FRAG_NEEDED) {
244 			harderr = inet->pmtudisc != IP_PMTUDISC_DONT;
245 			err = EMSGSIZE;
246 		}
247 	}
248 
249 	if (inet->recverr) {
250 		const struct iphdr *iph = (const struct iphdr *)skb->data;
251 		u8 *payload = skb->data + (iph->ihl << 2);
252 
253 		if (inet->hdrincl)
254 			payload = skb->data;
255 		ip_icmp_error(sk, skb, err, 0, info, payload);
256 	}
257 
258 	if (inet->recverr || harderr) {
259 		sk->sk_err = err;
260 		sk->sk_error_report(sk);
261 	}
262 }
263 
264 void raw_icmp_error(struct sk_buff *skb, int protocol, u32 info)
265 {
266 	int hash;
267 	struct sock *raw_sk;
268 	const struct iphdr *iph;
269 	struct net *net;
270 
271 	hash = protocol & (RAW_HTABLE_SIZE - 1);
272 
273 	read_lock(&raw_v4_hashinfo.lock);
274 	raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]);
275 	if (raw_sk != NULL) {
276 		iph = (const struct iphdr *)skb->data;
277 		net = dev_net(skb->dev);
278 
279 		while ((raw_sk = __raw_v4_lookup(net, raw_sk, protocol,
280 						iph->daddr, iph->saddr,
281 						skb->dev->ifindex)) != NULL) {
282 			raw_err(raw_sk, skb, info);
283 			raw_sk = sk_next(raw_sk);
284 			iph = (const struct iphdr *)skb->data;
285 		}
286 	}
287 	read_unlock(&raw_v4_hashinfo.lock);
288 }
289 
290 static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
291 {
292 	/* Charge it to the socket. */
293 
294 	if (ip_queue_rcv_skb(sk, skb) < 0) {
295 		kfree_skb(skb);
296 		return NET_RX_DROP;
297 	}
298 
299 	return NET_RX_SUCCESS;
300 }
301 
302 int raw_rcv(struct sock *sk, struct sk_buff *skb)
303 {
304 	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
305 		atomic_inc(&sk->sk_drops);
306 		kfree_skb(skb);
307 		return NET_RX_DROP;
308 	}
309 	nf_reset(skb);
310 
311 	skb_push(skb, skb->data - skb_network_header(skb));
312 
313 	raw_rcv_skb(sk, skb);
314 	return 0;
315 }
316 
317 static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
318 			   void *from, size_t length,
319 			   struct rtable **rtp,
320 			   unsigned int flags)
321 {
322 	struct inet_sock *inet = inet_sk(sk);
323 	struct net *net = sock_net(sk);
324 	struct iphdr *iph;
325 	struct sk_buff *skb;
326 	unsigned int iphlen;
327 	int err;
328 	struct rtable *rt = *rtp;
329 
330 	if (length > rt->dst.dev->mtu) {
331 		ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport,
332 			       rt->dst.dev->mtu);
333 		return -EMSGSIZE;
334 	}
335 	if (flags&MSG_PROBE)
336 		goto out;
337 
338 	skb = sock_alloc_send_skb(sk,
339 				  length + LL_ALLOCATED_SPACE(rt->dst.dev) + 15,
340 				  flags & MSG_DONTWAIT, &err);
341 	if (skb == NULL)
342 		goto error;
343 	skb_reserve(skb, LL_RESERVED_SPACE(rt->dst.dev));
344 
345 	skb->priority = sk->sk_priority;
346 	skb->mark = sk->sk_mark;
347 	skb_dst_set(skb, &rt->dst);
348 	*rtp = NULL;
349 
350 	skb_reset_network_header(skb);
351 	iph = ip_hdr(skb);
352 	skb_put(skb, length);
353 
354 	skb->ip_summed = CHECKSUM_NONE;
355 
356 	skb->transport_header = skb->network_header;
357 	err = -EFAULT;
358 	if (memcpy_fromiovecend((void *)iph, from, 0, length))
359 		goto error_free;
360 
361 	iphlen = iph->ihl * 4;
362 
363 	/*
364 	 * We don't want to modify the ip header, but we do need to
365 	 * be sure that it won't cause problems later along the network
366 	 * stack.  Specifically we want to make sure that iph->ihl is a
367 	 * sane value.  If ihl points beyond the length of the buffer passed
368 	 * in, reject the frame as invalid
369 	 */
370 	err = -EINVAL;
371 	if (iphlen > length)
372 		goto error_free;
373 
374 	if (iphlen >= sizeof(*iph)) {
375 		if (!iph->saddr)
376 			iph->saddr = fl4->saddr;
377 		iph->check   = 0;
378 		iph->tot_len = htons(length);
379 		if (!iph->id)
380 			ip_select_ident(iph, &rt->dst, NULL);
381 
382 		iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
383 	}
384 	if (iph->protocol == IPPROTO_ICMP)
385 		icmp_out_count(net, ((struct icmphdr *)
386 			skb_transport_header(skb))->type);
387 
388 	err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT, skb, NULL,
389 		      rt->dst.dev, dst_output);
390 	if (err > 0)
391 		err = net_xmit_errno(err);
392 	if (err)
393 		goto error;
394 out:
395 	return 0;
396 
397 error_free:
398 	kfree_skb(skb);
399 error:
400 	IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS);
401 	if (err == -ENOBUFS && !inet->recverr)
402 		err = 0;
403 	return err;
404 }
405 
406 static int raw_probe_proto_opt(struct flowi4 *fl4, struct msghdr *msg)
407 {
408 	struct iovec *iov;
409 	u8 __user *type = NULL;
410 	u8 __user *code = NULL;
411 	int probed = 0;
412 	unsigned int i;
413 
414 	if (!msg->msg_iov)
415 		return 0;
416 
417 	for (i = 0; i < msg->msg_iovlen; i++) {
418 		iov = &msg->msg_iov[i];
419 		if (!iov)
420 			continue;
421 
422 		switch (fl4->flowi4_proto) {
423 		case IPPROTO_ICMP:
424 			/* check if one-byte field is readable or not. */
425 			if (iov->iov_base && iov->iov_len < 1)
426 				break;
427 
428 			if (!type) {
429 				type = iov->iov_base;
430 				/* check if code field is readable or not. */
431 				if (iov->iov_len > 1)
432 					code = type + 1;
433 			} else if (!code)
434 				code = iov->iov_base;
435 
436 			if (type && code) {
437 				if (get_user(fl4->fl4_icmp_type, type) ||
438 				    get_user(fl4->fl4_icmp_code, code))
439 					return -EFAULT;
440 				probed = 1;
441 			}
442 			break;
443 		default:
444 			probed = 1;
445 			break;
446 		}
447 		if (probed)
448 			break;
449 	}
450 	return 0;
451 }
452 
453 static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
454 		       size_t len)
455 {
456 	struct inet_sock *inet = inet_sk(sk);
457 	struct ipcm_cookie ipc;
458 	struct rtable *rt = NULL;
459 	struct flowi4 fl4;
460 	int free = 0;
461 	__be32 daddr;
462 	__be32 saddr;
463 	u8  tos;
464 	int err;
465 	struct ip_options_data opt_copy;
466 
467 	err = -EMSGSIZE;
468 	if (len > 0xFFFF)
469 		goto out;
470 
471 	/*
472 	 *	Check the flags.
473 	 */
474 
475 	err = -EOPNOTSUPP;
476 	if (msg->msg_flags & MSG_OOB)	/* Mirror BSD error message */
477 		goto out;               /* compatibility */
478 
479 	/*
480 	 *	Get and verify the address.
481 	 */
482 
483 	if (msg->msg_namelen) {
484 		struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
485 		err = -EINVAL;
486 		if (msg->msg_namelen < sizeof(*usin))
487 			goto out;
488 		if (usin->sin_family != AF_INET) {
489 			static int complained;
490 			if (!complained++)
491 				printk(KERN_INFO "%s forgot to set AF_INET in "
492 						 "raw sendmsg. Fix it!\n",
493 						 current->comm);
494 			err = -EAFNOSUPPORT;
495 			if (usin->sin_family)
496 				goto out;
497 		}
498 		daddr = usin->sin_addr.s_addr;
499 		/* ANK: I did not forget to get protocol from port field.
500 		 * I just do not know, who uses this weirdness.
501 		 * IP_HDRINCL is much more convenient.
502 		 */
503 	} else {
504 		err = -EDESTADDRREQ;
505 		if (sk->sk_state != TCP_ESTABLISHED)
506 			goto out;
507 		daddr = inet->inet_daddr;
508 	}
509 
510 	ipc.addr = inet->inet_saddr;
511 	ipc.opt = NULL;
512 	ipc.tx_flags = 0;
513 	ipc.oif = sk->sk_bound_dev_if;
514 
515 	if (msg->msg_controllen) {
516 		err = ip_cmsg_send(sock_net(sk), msg, &ipc);
517 		if (err)
518 			goto out;
519 		if (ipc.opt)
520 			free = 1;
521 	}
522 
523 	saddr = ipc.addr;
524 	ipc.addr = daddr;
525 
526 	if (!ipc.opt) {
527 		struct ip_options_rcu *inet_opt;
528 
529 		rcu_read_lock();
530 		inet_opt = rcu_dereference(inet->inet_opt);
531 		if (inet_opt) {
532 			memcpy(&opt_copy, inet_opt,
533 			       sizeof(*inet_opt) + inet_opt->opt.optlen);
534 			ipc.opt = &opt_copy.opt;
535 		}
536 		rcu_read_unlock();
537 	}
538 
539 	if (ipc.opt) {
540 		err = -EINVAL;
541 		/* Linux does not mangle headers on raw sockets,
542 		 * so that IP options + IP_HDRINCL is non-sense.
543 		 */
544 		if (inet->hdrincl)
545 			goto done;
546 		if (ipc.opt->opt.srr) {
547 			if (!daddr)
548 				goto done;
549 			daddr = ipc.opt->opt.faddr;
550 		}
551 	}
552 	tos = RT_CONN_FLAGS(sk);
553 	if (msg->msg_flags & MSG_DONTROUTE)
554 		tos |= RTO_ONLINK;
555 
556 	if (ipv4_is_multicast(daddr)) {
557 		if (!ipc.oif)
558 			ipc.oif = inet->mc_index;
559 		if (!saddr)
560 			saddr = inet->mc_addr;
561 	}
562 
563 	flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
564 			   RT_SCOPE_UNIVERSE,
565 			   inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
566 			   FLOWI_FLAG_CAN_SLEEP, daddr, saddr, 0, 0);
567 
568 	if (!inet->hdrincl) {
569 		err = raw_probe_proto_opt(&fl4, msg);
570 		if (err)
571 			goto done;
572 	}
573 
574 	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
575 	rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
576 	if (IS_ERR(rt)) {
577 		err = PTR_ERR(rt);
578 		rt = NULL;
579 		goto done;
580 	}
581 
582 	err = -EACCES;
583 	if (rt->rt_flags & RTCF_BROADCAST && !sock_flag(sk, SOCK_BROADCAST))
584 		goto done;
585 
586 	if (msg->msg_flags & MSG_CONFIRM)
587 		goto do_confirm;
588 back_from_confirm:
589 
590 	if (inet->hdrincl)
591 		err = raw_send_hdrinc(sk, &fl4, msg->msg_iov, len,
592 				      &rt, msg->msg_flags);
593 
594 	 else {
595 		if (!ipc.addr)
596 			ipc.addr = fl4.daddr;
597 		lock_sock(sk);
598 		err = ip_append_data(sk, &fl4, ip_generic_getfrag,
599 				     msg->msg_iov, len, 0,
600 				     &ipc, &rt, msg->msg_flags);
601 		if (err)
602 			ip_flush_pending_frames(sk);
603 		else if (!(msg->msg_flags & MSG_MORE)) {
604 			err = ip_push_pending_frames(sk, &fl4);
605 			if (err == -ENOBUFS && !inet->recverr)
606 				err = 0;
607 		}
608 		release_sock(sk);
609 	}
610 done:
611 	if (free)
612 		kfree(ipc.opt);
613 	ip_rt_put(rt);
614 
615 out:
616 	if (err < 0)
617 		return err;
618 	return len;
619 
620 do_confirm:
621 	dst_confirm(&rt->dst);
622 	if (!(msg->msg_flags & MSG_PROBE) || len)
623 		goto back_from_confirm;
624 	err = 0;
625 	goto done;
626 }
627 
628 static void raw_close(struct sock *sk, long timeout)
629 {
630 	/*
631 	 * Raw sockets may have direct kernel references. Kill them.
632 	 */
633 	ip_ra_control(sk, 0, NULL);
634 
635 	sk_common_release(sk);
636 }
637 
638 static void raw_destroy(struct sock *sk)
639 {
640 	lock_sock(sk);
641 	ip_flush_pending_frames(sk);
642 	release_sock(sk);
643 }
644 
645 /* This gets rid of all the nasties in af_inet. -DaveM */
646 static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
647 {
648 	struct inet_sock *inet = inet_sk(sk);
649 	struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
650 	int ret = -EINVAL;
651 	int chk_addr_ret;
652 
653 	if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in))
654 		goto out;
655 	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
656 	ret = -EADDRNOTAVAIL;
657 	if (addr->sin_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
658 	    chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
659 		goto out;
660 	inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
661 	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
662 		inet->inet_saddr = 0;  /* Use device */
663 	sk_dst_reset(sk);
664 	ret = 0;
665 out:	return ret;
666 }
667 
668 /*
669  *	This should be easy, if there is something there
670  *	we return it, otherwise we block.
671  */
672 
673 static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
674 		       size_t len, int noblock, int flags, int *addr_len)
675 {
676 	struct inet_sock *inet = inet_sk(sk);
677 	size_t copied = 0;
678 	int err = -EOPNOTSUPP;
679 	struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
680 	struct sk_buff *skb;
681 
682 	if (flags & MSG_OOB)
683 		goto out;
684 
685 	if (addr_len)
686 		*addr_len = sizeof(*sin);
687 
688 	if (flags & MSG_ERRQUEUE) {
689 		err = ip_recv_error(sk, msg, len);
690 		goto out;
691 	}
692 
693 	skb = skb_recv_datagram(sk, flags, noblock, &err);
694 	if (!skb)
695 		goto out;
696 
697 	copied = skb->len;
698 	if (len < copied) {
699 		msg->msg_flags |= MSG_TRUNC;
700 		copied = len;
701 	}
702 
703 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
704 	if (err)
705 		goto done;
706 
707 	sock_recv_ts_and_drops(msg, sk, skb);
708 
709 	/* Copy the address. */
710 	if (sin) {
711 		sin->sin_family = AF_INET;
712 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
713 		sin->sin_port = 0;
714 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
715 	}
716 	if (inet->cmsg_flags)
717 		ip_cmsg_recv(msg, skb);
718 	if (flags & MSG_TRUNC)
719 		copied = skb->len;
720 done:
721 	skb_free_datagram(sk, skb);
722 out:
723 	if (err)
724 		return err;
725 	return copied;
726 }
727 
728 static int raw_init(struct sock *sk)
729 {
730 	struct raw_sock *rp = raw_sk(sk);
731 
732 	if (inet_sk(sk)->inet_num == IPPROTO_ICMP)
733 		memset(&rp->filter, 0, sizeof(rp->filter));
734 	return 0;
735 }
736 
737 static int raw_seticmpfilter(struct sock *sk, char __user *optval, int optlen)
738 {
739 	if (optlen > sizeof(struct icmp_filter))
740 		optlen = sizeof(struct icmp_filter);
741 	if (copy_from_user(&raw_sk(sk)->filter, optval, optlen))
742 		return -EFAULT;
743 	return 0;
744 }
745 
746 static int raw_geticmpfilter(struct sock *sk, char __user *optval, int __user *optlen)
747 {
748 	int len, ret = -EFAULT;
749 
750 	if (get_user(len, optlen))
751 		goto out;
752 	ret = -EINVAL;
753 	if (len < 0)
754 		goto out;
755 	if (len > sizeof(struct icmp_filter))
756 		len = sizeof(struct icmp_filter);
757 	ret = -EFAULT;
758 	if (put_user(len, optlen) ||
759 	    copy_to_user(optval, &raw_sk(sk)->filter, len))
760 		goto out;
761 	ret = 0;
762 out:	return ret;
763 }
764 
765 static int do_raw_setsockopt(struct sock *sk, int level, int optname,
766 			  char __user *optval, unsigned int optlen)
767 {
768 	if (optname == ICMP_FILTER) {
769 		if (inet_sk(sk)->inet_num != IPPROTO_ICMP)
770 			return -EOPNOTSUPP;
771 		else
772 			return raw_seticmpfilter(sk, optval, optlen);
773 	}
774 	return -ENOPROTOOPT;
775 }
776 
777 static int raw_setsockopt(struct sock *sk, int level, int optname,
778 			  char __user *optval, unsigned int optlen)
779 {
780 	if (level != SOL_RAW)
781 		return ip_setsockopt(sk, level, optname, optval, optlen);
782 	return do_raw_setsockopt(sk, level, optname, optval, optlen);
783 }
784 
785 #ifdef CONFIG_COMPAT
786 static int compat_raw_setsockopt(struct sock *sk, int level, int optname,
787 				 char __user *optval, unsigned int optlen)
788 {
789 	if (level != SOL_RAW)
790 		return compat_ip_setsockopt(sk, level, optname, optval, optlen);
791 	return do_raw_setsockopt(sk, level, optname, optval, optlen);
792 }
793 #endif
794 
795 static int do_raw_getsockopt(struct sock *sk, int level, int optname,
796 			  char __user *optval, int __user *optlen)
797 {
798 	if (optname == ICMP_FILTER) {
799 		if (inet_sk(sk)->inet_num != IPPROTO_ICMP)
800 			return -EOPNOTSUPP;
801 		else
802 			return raw_geticmpfilter(sk, optval, optlen);
803 	}
804 	return -ENOPROTOOPT;
805 }
806 
807 static int raw_getsockopt(struct sock *sk, int level, int optname,
808 			  char __user *optval, int __user *optlen)
809 {
810 	if (level != SOL_RAW)
811 		return ip_getsockopt(sk, level, optname, optval, optlen);
812 	return do_raw_getsockopt(sk, level, optname, optval, optlen);
813 }
814 
815 #ifdef CONFIG_COMPAT
816 static int compat_raw_getsockopt(struct sock *sk, int level, int optname,
817 				 char __user *optval, int __user *optlen)
818 {
819 	if (level != SOL_RAW)
820 		return compat_ip_getsockopt(sk, level, optname, optval, optlen);
821 	return do_raw_getsockopt(sk, level, optname, optval, optlen);
822 }
823 #endif
824 
825 static int raw_ioctl(struct sock *sk, int cmd, unsigned long arg)
826 {
827 	switch (cmd) {
828 	case SIOCOUTQ: {
829 		int amount = sk_wmem_alloc_get(sk);
830 
831 		return put_user(amount, (int __user *)arg);
832 	}
833 	case SIOCINQ: {
834 		struct sk_buff *skb;
835 		int amount = 0;
836 
837 		spin_lock_bh(&sk->sk_receive_queue.lock);
838 		skb = skb_peek(&sk->sk_receive_queue);
839 		if (skb != NULL)
840 			amount = skb->len;
841 		spin_unlock_bh(&sk->sk_receive_queue.lock);
842 		return put_user(amount, (int __user *)arg);
843 	}
844 
845 	default:
846 #ifdef CONFIG_IP_MROUTE
847 		return ipmr_ioctl(sk, cmd, (void __user *)arg);
848 #else
849 		return -ENOIOCTLCMD;
850 #endif
851 	}
852 }
853 
854 #ifdef CONFIG_COMPAT
855 static int compat_raw_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg)
856 {
857 	switch (cmd) {
858 	case SIOCOUTQ:
859 	case SIOCINQ:
860 		return -ENOIOCTLCMD;
861 	default:
862 #ifdef CONFIG_IP_MROUTE
863 		return ipmr_compat_ioctl(sk, cmd, compat_ptr(arg));
864 #else
865 		return -ENOIOCTLCMD;
866 #endif
867 	}
868 }
869 #endif
870 
871 struct proto raw_prot = {
872 	.name		   = "RAW",
873 	.owner		   = THIS_MODULE,
874 	.close		   = raw_close,
875 	.destroy	   = raw_destroy,
876 	.connect	   = ip4_datagram_connect,
877 	.disconnect	   = udp_disconnect,
878 	.ioctl		   = raw_ioctl,
879 	.init		   = raw_init,
880 	.setsockopt	   = raw_setsockopt,
881 	.getsockopt	   = raw_getsockopt,
882 	.sendmsg	   = raw_sendmsg,
883 	.recvmsg	   = raw_recvmsg,
884 	.bind		   = raw_bind,
885 	.backlog_rcv	   = raw_rcv_skb,
886 	.hash		   = raw_hash_sk,
887 	.unhash		   = raw_unhash_sk,
888 	.obj_size	   = sizeof(struct raw_sock),
889 	.h.raw_hash	   = &raw_v4_hashinfo,
890 #ifdef CONFIG_COMPAT
891 	.compat_setsockopt = compat_raw_setsockopt,
892 	.compat_getsockopt = compat_raw_getsockopt,
893 	.compat_ioctl	   = compat_raw_ioctl,
894 #endif
895 };
896 
897 #ifdef CONFIG_PROC_FS
898 static struct sock *raw_get_first(struct seq_file *seq)
899 {
900 	struct sock *sk;
901 	struct raw_iter_state *state = raw_seq_private(seq);
902 
903 	for (state->bucket = 0; state->bucket < RAW_HTABLE_SIZE;
904 			++state->bucket) {
905 		struct hlist_node *node;
906 
907 		sk_for_each(sk, node, &state->h->ht[state->bucket])
908 			if (sock_net(sk) == seq_file_net(seq))
909 				goto found;
910 	}
911 	sk = NULL;
912 found:
913 	return sk;
914 }
915 
916 static struct sock *raw_get_next(struct seq_file *seq, struct sock *sk)
917 {
918 	struct raw_iter_state *state = raw_seq_private(seq);
919 
920 	do {
921 		sk = sk_next(sk);
922 try_again:
923 		;
924 	} while (sk && sock_net(sk) != seq_file_net(seq));
925 
926 	if (!sk && ++state->bucket < RAW_HTABLE_SIZE) {
927 		sk = sk_head(&state->h->ht[state->bucket]);
928 		goto try_again;
929 	}
930 	return sk;
931 }
932 
933 static struct sock *raw_get_idx(struct seq_file *seq, loff_t pos)
934 {
935 	struct sock *sk = raw_get_first(seq);
936 
937 	if (sk)
938 		while (pos && (sk = raw_get_next(seq, sk)) != NULL)
939 			--pos;
940 	return pos ? NULL : sk;
941 }
942 
943 void *raw_seq_start(struct seq_file *seq, loff_t *pos)
944 {
945 	struct raw_iter_state *state = raw_seq_private(seq);
946 
947 	read_lock(&state->h->lock);
948 	return *pos ? raw_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
949 }
950 EXPORT_SYMBOL_GPL(raw_seq_start);
951 
952 void *raw_seq_next(struct seq_file *seq, void *v, loff_t *pos)
953 {
954 	struct sock *sk;
955 
956 	if (v == SEQ_START_TOKEN)
957 		sk = raw_get_first(seq);
958 	else
959 		sk = raw_get_next(seq, v);
960 	++*pos;
961 	return sk;
962 }
963 EXPORT_SYMBOL_GPL(raw_seq_next);
964 
965 void raw_seq_stop(struct seq_file *seq, void *v)
966 {
967 	struct raw_iter_state *state = raw_seq_private(seq);
968 
969 	read_unlock(&state->h->lock);
970 }
971 EXPORT_SYMBOL_GPL(raw_seq_stop);
972 
973 static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i)
974 {
975 	struct inet_sock *inet = inet_sk(sp);
976 	__be32 dest = inet->inet_daddr,
977 	       src = inet->inet_rcv_saddr;
978 	__u16 destp = 0,
979 	      srcp  = inet->inet_num;
980 
981 	seq_printf(seq, "%4d: %08X:%04X %08X:%04X"
982 		" %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
983 		i, src, srcp, dest, destp, sp->sk_state,
984 		sk_wmem_alloc_get(sp),
985 		sk_rmem_alloc_get(sp),
986 		0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
987 		atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops));
988 }
989 
990 static int raw_seq_show(struct seq_file *seq, void *v)
991 {
992 	if (v == SEQ_START_TOKEN)
993 		seq_printf(seq, "  sl  local_address rem_address   st tx_queue "
994 				"rx_queue tr tm->when retrnsmt   uid  timeout "
995 				"inode ref pointer drops\n");
996 	else
997 		raw_sock_seq_show(seq, v, raw_seq_private(seq)->bucket);
998 	return 0;
999 }
1000 
1001 static const struct seq_operations raw_seq_ops = {
1002 	.start = raw_seq_start,
1003 	.next  = raw_seq_next,
1004 	.stop  = raw_seq_stop,
1005 	.show  = raw_seq_show,
1006 };
1007 
1008 int raw_seq_open(struct inode *ino, struct file *file,
1009 		 struct raw_hashinfo *h, const struct seq_operations *ops)
1010 {
1011 	int err;
1012 	struct raw_iter_state *i;
1013 
1014 	err = seq_open_net(ino, file, ops, sizeof(struct raw_iter_state));
1015 	if (err < 0)
1016 		return err;
1017 
1018 	i = raw_seq_private((struct seq_file *)file->private_data);
1019 	i->h = h;
1020 	return 0;
1021 }
1022 EXPORT_SYMBOL_GPL(raw_seq_open);
1023 
1024 static int raw_v4_seq_open(struct inode *inode, struct file *file)
1025 {
1026 	return raw_seq_open(inode, file, &raw_v4_hashinfo, &raw_seq_ops);
1027 }
1028 
1029 static const struct file_operations raw_seq_fops = {
1030 	.owner	 = THIS_MODULE,
1031 	.open	 = raw_v4_seq_open,
1032 	.read	 = seq_read,
1033 	.llseek	 = seq_lseek,
1034 	.release = seq_release_net,
1035 };
1036 
1037 static __net_init int raw_init_net(struct net *net)
1038 {
1039 	if (!proc_net_fops_create(net, "raw", S_IRUGO, &raw_seq_fops))
1040 		return -ENOMEM;
1041 
1042 	return 0;
1043 }
1044 
1045 static __net_exit void raw_exit_net(struct net *net)
1046 {
1047 	proc_net_remove(net, "raw");
1048 }
1049 
1050 static __net_initdata struct pernet_operations raw_net_ops = {
1051 	.init = raw_init_net,
1052 	.exit = raw_exit_net,
1053 };
1054 
1055 int __init raw_proc_init(void)
1056 {
1057 	return register_pernet_subsys(&raw_net_ops);
1058 }
1059 
1060 void __init raw_proc_exit(void)
1061 {
1062 	unregister_pernet_subsys(&raw_net_ops);
1063 }
1064 #endif /* CONFIG_PROC_FS */
1065