xref: /linux/net/ipv4/raw.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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/export.h>
52 #include <linux/spinlock.h>
53 #include <linux/sockios.h>
54 #include <linux/socket.h>
55 #include <linux/in.h>
56 #include <linux/mroute.h>
57 #include <linux/netdevice.h>
58 #include <linux/in_route.h>
59 #include <linux/route.h>
60 #include <linux/skbuff.h>
61 #include <net/net_namespace.h>
62 #include <net/dst.h>
63 #include <net/sock.h>
64 #include <linux/ip.h>
65 #include <linux/net.h>
66 #include <net/ip.h>
67 #include <net/icmp.h>
68 #include <net/udp.h>
69 #include <net/raw.h>
70 #include <net/snmp.h>
71 #include <net/tcp_states.h>
72 #include <net/inet_common.h>
73 #include <net/checksum.h>
74 #include <net/xfrm.h>
75 #include <linux/rtnetlink.h>
76 #include <linux/proc_fs.h>
77 #include <linux/seq_file.h>
78 #include <linux/netfilter.h>
79 #include <linux/netfilter_ipv4.h>
80 #include <linux/compat.h>
81 
82 static struct raw_hashinfo raw_v4_hashinfo = {
83 	.lock = __RW_LOCK_UNLOCKED(raw_v4_hashinfo.lock),
84 };
85 
86 void raw_hash_sk(struct sock *sk)
87 {
88 	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
89 	struct hlist_head *head;
90 
91 	head = &h->ht[inet_sk(sk)->inet_num & (RAW_HTABLE_SIZE - 1)];
92 
93 	write_lock_bh(&h->lock);
94 	sk_add_node(sk, head);
95 	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
96 	write_unlock_bh(&h->lock);
97 }
98 EXPORT_SYMBOL_GPL(raw_hash_sk);
99 
100 void raw_unhash_sk(struct sock *sk)
101 {
102 	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
103 
104 	write_lock_bh(&h->lock);
105 	if (sk_del_node_init(sk))
106 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
107 	write_unlock_bh(&h->lock);
108 }
109 EXPORT_SYMBOL_GPL(raw_unhash_sk);
110 
111 static struct sock *__raw_v4_lookup(struct net *net, struct sock *sk,
112 		unsigned short num, __be32 raddr, __be32 laddr, int dif)
113 {
114 	struct hlist_node *node;
115 
116 	sk_for_each_from(sk, node) {
117 		struct inet_sock *inet = inet_sk(sk);
118 
119 		if (net_eq(sock_net(sk), net) && inet->inet_num == num	&&
120 		    !(inet->inet_daddr && inet->inet_daddr != raddr) 	&&
121 		    !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) &&
122 		    !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
123 			goto found; /* gotcha */
124 	}
125 	sk = NULL;
126 found:
127 	return sk;
128 }
129 
130 /*
131  *	0 - deliver
132  *	1 - block
133  */
134 static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb)
135 {
136 	int type;
137 
138 	if (!pskb_may_pull(skb, sizeof(struct icmphdr)))
139 		return 1;
140 
141 	type = icmp_hdr(skb)->type;
142 	if (type < 32) {
143 		__u32 data = raw_sk(sk)->filter.data;
144 
145 		return ((1 << type) & data) != 0;
146 	}
147 
148 	/* Do not block unknown ICMP types */
149 	return 0;
150 }
151 
152 /* IP input processing comes here for RAW socket delivery.
153  * Caller owns SKB, so we must make clones.
154  *
155  * RFC 1122: SHOULD pass TOS value up to the transport layer.
156  * -> It does. And not only TOS, but all IP header.
157  */
158 static int raw_v4_input(struct sk_buff *skb, const struct iphdr *iph, int hash)
159 {
160 	struct sock *sk;
161 	struct hlist_head *head;
162 	int delivered = 0;
163 	struct net *net;
164 
165 	read_lock(&raw_v4_hashinfo.lock);
166 	head = &raw_v4_hashinfo.ht[hash];
167 	if (hlist_empty(head))
168 		goto out;
169 
170 	net = dev_net(skb->dev);
171 	sk = __raw_v4_lookup(net, __sk_head(head), iph->protocol,
172 			     iph->saddr, iph->daddr,
173 			     skb->dev->ifindex);
174 
175 	while (sk) {
176 		delivered = 1;
177 		if (iph->protocol != IPPROTO_ICMP || !icmp_filter(sk, skb)) {
178 			struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
179 
180 			/* Not releasing hash table! */
181 			if (clone)
182 				raw_rcv(sk, clone);
183 		}
184 		sk = __raw_v4_lookup(net, sk_next(sk), iph->protocol,
185 				     iph->saddr, iph->daddr,
186 				     skb->dev->ifindex);
187 	}
188 out:
189 	read_unlock(&raw_v4_hashinfo.lock);
190 	return delivered;
191 }
192 
193 int raw_local_deliver(struct sk_buff *skb, int protocol)
194 {
195 	int hash;
196 	struct sock *raw_sk;
197 
198 	hash = protocol & (RAW_HTABLE_SIZE - 1);
199 	raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]);
200 
201 	/* If there maybe a raw socket we must check - if not we
202 	 * don't care less
203 	 */
204 	if (raw_sk && !raw_v4_input(skb, ip_hdr(skb), hash))
205 		raw_sk = NULL;
206 
207 	return raw_sk != NULL;
208 
209 }
210 
211 static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info)
212 {
213 	struct inet_sock *inet = inet_sk(sk);
214 	const int type = icmp_hdr(skb)->type;
215 	const int code = icmp_hdr(skb)->code;
216 	int err = 0;
217 	int harderr = 0;
218 
219 	/* Report error on raw socket, if:
220 	   1. User requested ip_recverr.
221 	   2. Socket is connected (otherwise the error indication
222 	      is useless without ip_recverr and error is hard.
223 	 */
224 	if (!inet->recverr && sk->sk_state != TCP_ESTABLISHED)
225 		return;
226 
227 	switch (type) {
228 	default:
229 	case ICMP_TIME_EXCEEDED:
230 		err = EHOSTUNREACH;
231 		break;
232 	case ICMP_SOURCE_QUENCH:
233 		return;
234 	case ICMP_PARAMETERPROB:
235 		err = EPROTO;
236 		harderr = 1;
237 		break;
238 	case ICMP_DEST_UNREACH:
239 		err = EHOSTUNREACH;
240 		if (code > NR_ICMP_UNREACH)
241 			break;
242 		err = icmp_err_convert[code].errno;
243 		harderr = icmp_err_convert[code].fatal;
244 		if (code == ICMP_FRAG_NEEDED) {
245 			harderr = inet->pmtudisc != IP_PMTUDISC_DONT;
246 			err = EMSGSIZE;
247 		}
248 	}
249 
250 	if (inet->recverr) {
251 		const struct iphdr *iph = (const struct iphdr *)skb->data;
252 		u8 *payload = skb->data + (iph->ihl << 2);
253 
254 		if (inet->hdrincl)
255 			payload = skb->data;
256 		ip_icmp_error(sk, skb, err, 0, info, payload);
257 	}
258 
259 	if (inet->recverr || harderr) {
260 		sk->sk_err = err;
261 		sk->sk_error_report(sk);
262 	}
263 }
264 
265 void raw_icmp_error(struct sk_buff *skb, int protocol, u32 info)
266 {
267 	int hash;
268 	struct sock *raw_sk;
269 	const struct iphdr *iph;
270 	struct net *net;
271 
272 	hash = protocol & (RAW_HTABLE_SIZE - 1);
273 
274 	read_lock(&raw_v4_hashinfo.lock);
275 	raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]);
276 	if (raw_sk != NULL) {
277 		iph = (const struct iphdr *)skb->data;
278 		net = dev_net(skb->dev);
279 
280 		while ((raw_sk = __raw_v4_lookup(net, raw_sk, protocol,
281 						iph->daddr, iph->saddr,
282 						skb->dev->ifindex)) != NULL) {
283 			raw_err(raw_sk, skb, info);
284 			raw_sk = sk_next(raw_sk);
285 			iph = (const struct iphdr *)skb->data;
286 		}
287 	}
288 	read_unlock(&raw_v4_hashinfo.lock);
289 }
290 
291 static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb)
292 {
293 	/* Charge it to the socket. */
294 
295 	if (ip_queue_rcv_skb(sk, skb) < 0) {
296 		kfree_skb(skb);
297 		return NET_RX_DROP;
298 	}
299 
300 	return NET_RX_SUCCESS;
301 }
302 
303 int raw_rcv(struct sock *sk, struct sk_buff *skb)
304 {
305 	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
306 		atomic_inc(&sk->sk_drops);
307 		kfree_skb(skb);
308 		return NET_RX_DROP;
309 	}
310 	nf_reset(skb);
311 
312 	skb_push(skb, skb->data - skb_network_header(skb));
313 
314 	raw_rcv_skb(sk, skb);
315 	return 0;
316 }
317 
318 static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
319 			   void *from, size_t length,
320 			   struct rtable **rtp,
321 			   unsigned int flags)
322 {
323 	struct inet_sock *inet = inet_sk(sk);
324 	struct net *net = sock_net(sk);
325 	struct iphdr *iph;
326 	struct sk_buff *skb;
327 	unsigned int iphlen;
328 	int err;
329 	struct rtable *rt = *rtp;
330 
331 	if (length > rt->dst.dev->mtu) {
332 		ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport,
333 			       rt->dst.dev->mtu);
334 		return -EMSGSIZE;
335 	}
336 	if (flags&MSG_PROBE)
337 		goto out;
338 
339 	skb = sock_alloc_send_skb(sk,
340 				  length + LL_ALLOCATED_SPACE(rt->dst.dev) + 15,
341 				  flags & MSG_DONTWAIT, &err);
342 	if (skb == NULL)
343 		goto error;
344 	skb_reserve(skb, LL_RESERVED_SPACE(rt->dst.dev));
345 
346 	skb->priority = sk->sk_priority;
347 	skb->mark = sk->sk_mark;
348 	skb_dst_set(skb, &rt->dst);
349 	*rtp = NULL;
350 
351 	skb_reset_network_header(skb);
352 	iph = ip_hdr(skb);
353 	skb_put(skb, length);
354 
355 	skb->ip_summed = CHECKSUM_NONE;
356 
357 	skb->transport_header = skb->network_header;
358 	err = -EFAULT;
359 	if (memcpy_fromiovecend((void *)iph, from, 0, length))
360 		goto error_free;
361 
362 	iphlen = iph->ihl * 4;
363 
364 	/*
365 	 * We don't want to modify the ip header, but we do need to
366 	 * be sure that it won't cause problems later along the network
367 	 * stack.  Specifically we want to make sure that iph->ihl is a
368 	 * sane value.  If ihl points beyond the length of the buffer passed
369 	 * in, reject the frame as invalid
370 	 */
371 	err = -EINVAL;
372 	if (iphlen > length)
373 		goto error_free;
374 
375 	if (iphlen >= sizeof(*iph)) {
376 		if (!iph->saddr)
377 			iph->saddr = fl4->saddr;
378 		iph->check   = 0;
379 		iph->tot_len = htons(length);
380 		if (!iph->id)
381 			ip_select_ident(iph, &rt->dst, NULL);
382 
383 		iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
384 	}
385 	if (iph->protocol == IPPROTO_ICMP)
386 		icmp_out_count(net, ((struct icmphdr *)
387 			skb_transport_header(skb))->type);
388 
389 	err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT, skb, NULL,
390 		      rt->dst.dev, dst_output);
391 	if (err > 0)
392 		err = net_xmit_errno(err);
393 	if (err)
394 		goto error;
395 out:
396 	return 0;
397 
398 error_free:
399 	kfree_skb(skb);
400 error:
401 	IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS);
402 	if (err == -ENOBUFS && !inet->recverr)
403 		err = 0;
404 	return err;
405 }
406 
407 static int raw_probe_proto_opt(struct flowi4 *fl4, struct msghdr *msg)
408 {
409 	struct iovec *iov;
410 	u8 __user *type = NULL;
411 	u8 __user *code = NULL;
412 	int probed = 0;
413 	unsigned int i;
414 
415 	if (!msg->msg_iov)
416 		return 0;
417 
418 	for (i = 0; i < msg->msg_iovlen; i++) {
419 		iov = &msg->msg_iov[i];
420 		if (!iov)
421 			continue;
422 
423 		switch (fl4->flowi4_proto) {
424 		case IPPROTO_ICMP:
425 			/* check if one-byte field is readable or not. */
426 			if (iov->iov_base && iov->iov_len < 1)
427 				break;
428 
429 			if (!type) {
430 				type = iov->iov_base;
431 				/* check if code field is readable or not. */
432 				if (iov->iov_len > 1)
433 					code = type + 1;
434 			} else if (!code)
435 				code = iov->iov_base;
436 
437 			if (type && code) {
438 				if (get_user(fl4->fl4_icmp_type, type) ||
439 				    get_user(fl4->fl4_icmp_code, code))
440 					return -EFAULT;
441 				probed = 1;
442 			}
443 			break;
444 		default:
445 			probed = 1;
446 			break;
447 		}
448 		if (probed)
449 			break;
450 	}
451 	return 0;
452 }
453 
454 static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
455 		       size_t len)
456 {
457 	struct inet_sock *inet = inet_sk(sk);
458 	struct ipcm_cookie ipc;
459 	struct rtable *rt = NULL;
460 	struct flowi4 fl4;
461 	int free = 0;
462 	__be32 daddr;
463 	__be32 saddr;
464 	u8  tos;
465 	int err;
466 	struct ip_options_data opt_copy;
467 
468 	err = -EMSGSIZE;
469 	if (len > 0xFFFF)
470 		goto out;
471 
472 	/*
473 	 *	Check the flags.
474 	 */
475 
476 	err = -EOPNOTSUPP;
477 	if (msg->msg_flags & MSG_OOB)	/* Mirror BSD error message */
478 		goto out;               /* compatibility */
479 
480 	/*
481 	 *	Get and verify the address.
482 	 */
483 
484 	if (msg->msg_namelen) {
485 		struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
486 		err = -EINVAL;
487 		if (msg->msg_namelen < sizeof(*usin))
488 			goto out;
489 		if (usin->sin_family != AF_INET) {
490 			static int complained;
491 			if (!complained++)
492 				printk(KERN_INFO "%s forgot to set AF_INET in "
493 						 "raw sendmsg. Fix it!\n",
494 						 current->comm);
495 			err = -EAFNOSUPPORT;
496 			if (usin->sin_family)
497 				goto out;
498 		}
499 		daddr = usin->sin_addr.s_addr;
500 		/* ANK: I did not forget to get protocol from port field.
501 		 * I just do not know, who uses this weirdness.
502 		 * IP_HDRINCL is much more convenient.
503 		 */
504 	} else {
505 		err = -EDESTADDRREQ;
506 		if (sk->sk_state != TCP_ESTABLISHED)
507 			goto out;
508 		daddr = inet->inet_daddr;
509 	}
510 
511 	ipc.addr = inet->inet_saddr;
512 	ipc.opt = NULL;
513 	ipc.tx_flags = 0;
514 	ipc.oif = sk->sk_bound_dev_if;
515 
516 	if (msg->msg_controllen) {
517 		err = ip_cmsg_send(sock_net(sk), msg, &ipc);
518 		if (err)
519 			goto out;
520 		if (ipc.opt)
521 			free = 1;
522 	}
523 
524 	saddr = ipc.addr;
525 	ipc.addr = daddr;
526 
527 	if (!ipc.opt) {
528 		struct ip_options_rcu *inet_opt;
529 
530 		rcu_read_lock();
531 		inet_opt = rcu_dereference(inet->inet_opt);
532 		if (inet_opt) {
533 			memcpy(&opt_copy, inet_opt,
534 			       sizeof(*inet_opt) + inet_opt->opt.optlen);
535 			ipc.opt = &opt_copy.opt;
536 		}
537 		rcu_read_unlock();
538 	}
539 
540 	if (ipc.opt) {
541 		err = -EINVAL;
542 		/* Linux does not mangle headers on raw sockets,
543 		 * so that IP options + IP_HDRINCL is non-sense.
544 		 */
545 		if (inet->hdrincl)
546 			goto done;
547 		if (ipc.opt->opt.srr) {
548 			if (!daddr)
549 				goto done;
550 			daddr = ipc.opt->opt.faddr;
551 		}
552 	}
553 	tos = RT_CONN_FLAGS(sk);
554 	if (msg->msg_flags & MSG_DONTROUTE)
555 		tos |= RTO_ONLINK;
556 
557 	if (ipv4_is_multicast(daddr)) {
558 		if (!ipc.oif)
559 			ipc.oif = inet->mc_index;
560 		if (!saddr)
561 			saddr = inet->mc_addr;
562 	}
563 
564 	flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
565 			   RT_SCOPE_UNIVERSE,
566 			   inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
567 			   inet_sk_flowi_flags(sk) | FLOWI_FLAG_CAN_SLEEP,
568 			   daddr, saddr, 0, 0);
569 
570 	if (!inet->hdrincl) {
571 		err = raw_probe_proto_opt(&fl4, msg);
572 		if (err)
573 			goto done;
574 	}
575 
576 	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
577 	rt = ip_route_output_flow(sock_net(sk), &fl4, sk);
578 	if (IS_ERR(rt)) {
579 		err = PTR_ERR(rt);
580 		rt = NULL;
581 		goto done;
582 	}
583 
584 	err = -EACCES;
585 	if (rt->rt_flags & RTCF_BROADCAST && !sock_flag(sk, SOCK_BROADCAST))
586 		goto done;
587 
588 	if (msg->msg_flags & MSG_CONFIRM)
589 		goto do_confirm;
590 back_from_confirm:
591 
592 	if (inet->hdrincl)
593 		err = raw_send_hdrinc(sk, &fl4, msg->msg_iov, len,
594 				      &rt, msg->msg_flags);
595 
596 	 else {
597 		if (!ipc.addr)
598 			ipc.addr = fl4.daddr;
599 		lock_sock(sk);
600 		err = ip_append_data(sk, &fl4, ip_generic_getfrag,
601 				     msg->msg_iov, len, 0,
602 				     &ipc, &rt, msg->msg_flags);
603 		if (err)
604 			ip_flush_pending_frames(sk);
605 		else if (!(msg->msg_flags & MSG_MORE)) {
606 			err = ip_push_pending_frames(sk, &fl4);
607 			if (err == -ENOBUFS && !inet->recverr)
608 				err = 0;
609 		}
610 		release_sock(sk);
611 	}
612 done:
613 	if (free)
614 		kfree(ipc.opt);
615 	ip_rt_put(rt);
616 
617 out:
618 	if (err < 0)
619 		return err;
620 	return len;
621 
622 do_confirm:
623 	dst_confirm(&rt->dst);
624 	if (!(msg->msg_flags & MSG_PROBE) || len)
625 		goto back_from_confirm;
626 	err = 0;
627 	goto done;
628 }
629 
630 static void raw_close(struct sock *sk, long timeout)
631 {
632 	/*
633 	 * Raw sockets may have direct kernel references. Kill them.
634 	 */
635 	ip_ra_control(sk, 0, NULL);
636 
637 	sk_common_release(sk);
638 }
639 
640 static void raw_destroy(struct sock *sk)
641 {
642 	lock_sock(sk);
643 	ip_flush_pending_frames(sk);
644 	release_sock(sk);
645 }
646 
647 /* This gets rid of all the nasties in af_inet. -DaveM */
648 static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
649 {
650 	struct inet_sock *inet = inet_sk(sk);
651 	struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
652 	int ret = -EINVAL;
653 	int chk_addr_ret;
654 
655 	if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in))
656 		goto out;
657 	chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
658 	ret = -EADDRNOTAVAIL;
659 	if (addr->sin_addr.s_addr && chk_addr_ret != RTN_LOCAL &&
660 	    chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST)
661 		goto out;
662 	inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
663 	if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
664 		inet->inet_saddr = 0;  /* Use device */
665 	sk_dst_reset(sk);
666 	ret = 0;
667 out:	return ret;
668 }
669 
670 /*
671  *	This should be easy, if there is something there
672  *	we return it, otherwise we block.
673  */
674 
675 static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
676 		       size_t len, int noblock, int flags, int *addr_len)
677 {
678 	struct inet_sock *inet = inet_sk(sk);
679 	size_t copied = 0;
680 	int err = -EOPNOTSUPP;
681 	struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
682 	struct sk_buff *skb;
683 
684 	if (flags & MSG_OOB)
685 		goto out;
686 
687 	if (addr_len)
688 		*addr_len = sizeof(*sin);
689 
690 	if (flags & MSG_ERRQUEUE) {
691 		err = ip_recv_error(sk, msg, len);
692 		goto out;
693 	}
694 
695 	skb = skb_recv_datagram(sk, flags, noblock, &err);
696 	if (!skb)
697 		goto out;
698 
699 	copied = skb->len;
700 	if (len < copied) {
701 		msg->msg_flags |= MSG_TRUNC;
702 		copied = len;
703 	}
704 
705 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
706 	if (err)
707 		goto done;
708 
709 	sock_recv_ts_and_drops(msg, sk, skb);
710 
711 	/* Copy the address. */
712 	if (sin) {
713 		sin->sin_family = AF_INET;
714 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
715 		sin->sin_port = 0;
716 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
717 	}
718 	if (inet->cmsg_flags)
719 		ip_cmsg_recv(msg, skb);
720 	if (flags & MSG_TRUNC)
721 		copied = skb->len;
722 done:
723 	skb_free_datagram(sk, skb);
724 out:
725 	if (err)
726 		return err;
727 	return copied;
728 }
729 
730 static int raw_init(struct sock *sk)
731 {
732 	struct raw_sock *rp = raw_sk(sk);
733 
734 	if (inet_sk(sk)->inet_num == IPPROTO_ICMP)
735 		memset(&rp->filter, 0, sizeof(rp->filter));
736 	return 0;
737 }
738 
739 static int raw_seticmpfilter(struct sock *sk, char __user *optval, int optlen)
740 {
741 	if (optlen > sizeof(struct icmp_filter))
742 		optlen = sizeof(struct icmp_filter);
743 	if (copy_from_user(&raw_sk(sk)->filter, optval, optlen))
744 		return -EFAULT;
745 	return 0;
746 }
747 
748 static int raw_geticmpfilter(struct sock *sk, char __user *optval, int __user *optlen)
749 {
750 	int len, ret = -EFAULT;
751 
752 	if (get_user(len, optlen))
753 		goto out;
754 	ret = -EINVAL;
755 	if (len < 0)
756 		goto out;
757 	if (len > sizeof(struct icmp_filter))
758 		len = sizeof(struct icmp_filter);
759 	ret = -EFAULT;
760 	if (put_user(len, optlen) ||
761 	    copy_to_user(optval, &raw_sk(sk)->filter, len))
762 		goto out;
763 	ret = 0;
764 out:	return ret;
765 }
766 
767 static int do_raw_setsockopt(struct sock *sk, int level, int optname,
768 			  char __user *optval, unsigned int optlen)
769 {
770 	if (optname == ICMP_FILTER) {
771 		if (inet_sk(sk)->inet_num != IPPROTO_ICMP)
772 			return -EOPNOTSUPP;
773 		else
774 			return raw_seticmpfilter(sk, optval, optlen);
775 	}
776 	return -ENOPROTOOPT;
777 }
778 
779 static int raw_setsockopt(struct sock *sk, int level, int optname,
780 			  char __user *optval, unsigned int optlen)
781 {
782 	if (level != SOL_RAW)
783 		return ip_setsockopt(sk, level, optname, optval, optlen);
784 	return do_raw_setsockopt(sk, level, optname, optval, optlen);
785 }
786 
787 #ifdef CONFIG_COMPAT
788 static int compat_raw_setsockopt(struct sock *sk, int level, int optname,
789 				 char __user *optval, unsigned int optlen)
790 {
791 	if (level != SOL_RAW)
792 		return compat_ip_setsockopt(sk, level, optname, optval, optlen);
793 	return do_raw_setsockopt(sk, level, optname, optval, optlen);
794 }
795 #endif
796 
797 static int do_raw_getsockopt(struct sock *sk, int level, int optname,
798 			  char __user *optval, int __user *optlen)
799 {
800 	if (optname == ICMP_FILTER) {
801 		if (inet_sk(sk)->inet_num != IPPROTO_ICMP)
802 			return -EOPNOTSUPP;
803 		else
804 			return raw_geticmpfilter(sk, optval, optlen);
805 	}
806 	return -ENOPROTOOPT;
807 }
808 
809 static int raw_getsockopt(struct sock *sk, int level, int optname,
810 			  char __user *optval, int __user *optlen)
811 {
812 	if (level != SOL_RAW)
813 		return ip_getsockopt(sk, level, optname, optval, optlen);
814 	return do_raw_getsockopt(sk, level, optname, optval, optlen);
815 }
816 
817 #ifdef CONFIG_COMPAT
818 static int compat_raw_getsockopt(struct sock *sk, int level, int optname,
819 				 char __user *optval, int __user *optlen)
820 {
821 	if (level != SOL_RAW)
822 		return compat_ip_getsockopt(sk, level, optname, optval, optlen);
823 	return do_raw_getsockopt(sk, level, optname, optval, optlen);
824 }
825 #endif
826 
827 static int raw_ioctl(struct sock *sk, int cmd, unsigned long arg)
828 {
829 	switch (cmd) {
830 	case SIOCOUTQ: {
831 		int amount = sk_wmem_alloc_get(sk);
832 
833 		return put_user(amount, (int __user *)arg);
834 	}
835 	case SIOCINQ: {
836 		struct sk_buff *skb;
837 		int amount = 0;
838 
839 		spin_lock_bh(&sk->sk_receive_queue.lock);
840 		skb = skb_peek(&sk->sk_receive_queue);
841 		if (skb != NULL)
842 			amount = skb->len;
843 		spin_unlock_bh(&sk->sk_receive_queue.lock);
844 		return put_user(amount, (int __user *)arg);
845 	}
846 
847 	default:
848 #ifdef CONFIG_IP_MROUTE
849 		return ipmr_ioctl(sk, cmd, (void __user *)arg);
850 #else
851 		return -ENOIOCTLCMD;
852 #endif
853 	}
854 }
855 
856 #ifdef CONFIG_COMPAT
857 static int compat_raw_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg)
858 {
859 	switch (cmd) {
860 	case SIOCOUTQ:
861 	case SIOCINQ:
862 		return -ENOIOCTLCMD;
863 	default:
864 #ifdef CONFIG_IP_MROUTE
865 		return ipmr_compat_ioctl(sk, cmd, compat_ptr(arg));
866 #else
867 		return -ENOIOCTLCMD;
868 #endif
869 	}
870 }
871 #endif
872 
873 struct proto raw_prot = {
874 	.name		   = "RAW",
875 	.owner		   = THIS_MODULE,
876 	.close		   = raw_close,
877 	.destroy	   = raw_destroy,
878 	.connect	   = ip4_datagram_connect,
879 	.disconnect	   = udp_disconnect,
880 	.ioctl		   = raw_ioctl,
881 	.init		   = raw_init,
882 	.setsockopt	   = raw_setsockopt,
883 	.getsockopt	   = raw_getsockopt,
884 	.sendmsg	   = raw_sendmsg,
885 	.recvmsg	   = raw_recvmsg,
886 	.bind		   = raw_bind,
887 	.backlog_rcv	   = raw_rcv_skb,
888 	.hash		   = raw_hash_sk,
889 	.unhash		   = raw_unhash_sk,
890 	.obj_size	   = sizeof(struct raw_sock),
891 	.h.raw_hash	   = &raw_v4_hashinfo,
892 #ifdef CONFIG_COMPAT
893 	.compat_setsockopt = compat_raw_setsockopt,
894 	.compat_getsockopt = compat_raw_getsockopt,
895 	.compat_ioctl	   = compat_raw_ioctl,
896 #endif
897 };
898 
899 #ifdef CONFIG_PROC_FS
900 static struct sock *raw_get_first(struct seq_file *seq)
901 {
902 	struct sock *sk;
903 	struct raw_iter_state *state = raw_seq_private(seq);
904 
905 	for (state->bucket = 0; state->bucket < RAW_HTABLE_SIZE;
906 			++state->bucket) {
907 		struct hlist_node *node;
908 
909 		sk_for_each(sk, node, &state->h->ht[state->bucket])
910 			if (sock_net(sk) == seq_file_net(seq))
911 				goto found;
912 	}
913 	sk = NULL;
914 found:
915 	return sk;
916 }
917 
918 static struct sock *raw_get_next(struct seq_file *seq, struct sock *sk)
919 {
920 	struct raw_iter_state *state = raw_seq_private(seq);
921 
922 	do {
923 		sk = sk_next(sk);
924 try_again:
925 		;
926 	} while (sk && sock_net(sk) != seq_file_net(seq));
927 
928 	if (!sk && ++state->bucket < RAW_HTABLE_SIZE) {
929 		sk = sk_head(&state->h->ht[state->bucket]);
930 		goto try_again;
931 	}
932 	return sk;
933 }
934 
935 static struct sock *raw_get_idx(struct seq_file *seq, loff_t pos)
936 {
937 	struct sock *sk = raw_get_first(seq);
938 
939 	if (sk)
940 		while (pos && (sk = raw_get_next(seq, sk)) != NULL)
941 			--pos;
942 	return pos ? NULL : sk;
943 }
944 
945 void *raw_seq_start(struct seq_file *seq, loff_t *pos)
946 {
947 	struct raw_iter_state *state = raw_seq_private(seq);
948 
949 	read_lock(&state->h->lock);
950 	return *pos ? raw_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
951 }
952 EXPORT_SYMBOL_GPL(raw_seq_start);
953 
954 void *raw_seq_next(struct seq_file *seq, void *v, loff_t *pos)
955 {
956 	struct sock *sk;
957 
958 	if (v == SEQ_START_TOKEN)
959 		sk = raw_get_first(seq);
960 	else
961 		sk = raw_get_next(seq, v);
962 	++*pos;
963 	return sk;
964 }
965 EXPORT_SYMBOL_GPL(raw_seq_next);
966 
967 void raw_seq_stop(struct seq_file *seq, void *v)
968 {
969 	struct raw_iter_state *state = raw_seq_private(seq);
970 
971 	read_unlock(&state->h->lock);
972 }
973 EXPORT_SYMBOL_GPL(raw_seq_stop);
974 
975 static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i)
976 {
977 	struct inet_sock *inet = inet_sk(sp);
978 	__be32 dest = inet->inet_daddr,
979 	       src = inet->inet_rcv_saddr;
980 	__u16 destp = 0,
981 	      srcp  = inet->inet_num;
982 
983 	seq_printf(seq, "%4d: %08X:%04X %08X:%04X"
984 		" %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d\n",
985 		i, src, srcp, dest, destp, sp->sk_state,
986 		sk_wmem_alloc_get(sp),
987 		sk_rmem_alloc_get(sp),
988 		0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
989 		atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops));
990 }
991 
992 static int raw_seq_show(struct seq_file *seq, void *v)
993 {
994 	if (v == SEQ_START_TOKEN)
995 		seq_printf(seq, "  sl  local_address rem_address   st tx_queue "
996 				"rx_queue tr tm->when retrnsmt   uid  timeout "
997 				"inode ref pointer drops\n");
998 	else
999 		raw_sock_seq_show(seq, v, raw_seq_private(seq)->bucket);
1000 	return 0;
1001 }
1002 
1003 static const struct seq_operations raw_seq_ops = {
1004 	.start = raw_seq_start,
1005 	.next  = raw_seq_next,
1006 	.stop  = raw_seq_stop,
1007 	.show  = raw_seq_show,
1008 };
1009 
1010 int raw_seq_open(struct inode *ino, struct file *file,
1011 		 struct raw_hashinfo *h, const struct seq_operations *ops)
1012 {
1013 	int err;
1014 	struct raw_iter_state *i;
1015 
1016 	err = seq_open_net(ino, file, ops, sizeof(struct raw_iter_state));
1017 	if (err < 0)
1018 		return err;
1019 
1020 	i = raw_seq_private((struct seq_file *)file->private_data);
1021 	i->h = h;
1022 	return 0;
1023 }
1024 EXPORT_SYMBOL_GPL(raw_seq_open);
1025 
1026 static int raw_v4_seq_open(struct inode *inode, struct file *file)
1027 {
1028 	return raw_seq_open(inode, file, &raw_v4_hashinfo, &raw_seq_ops);
1029 }
1030 
1031 static const struct file_operations raw_seq_fops = {
1032 	.owner	 = THIS_MODULE,
1033 	.open	 = raw_v4_seq_open,
1034 	.read	 = seq_read,
1035 	.llseek	 = seq_lseek,
1036 	.release = seq_release_net,
1037 };
1038 
1039 static __net_init int raw_init_net(struct net *net)
1040 {
1041 	if (!proc_net_fops_create(net, "raw", S_IRUGO, &raw_seq_fops))
1042 		return -ENOMEM;
1043 
1044 	return 0;
1045 }
1046 
1047 static __net_exit void raw_exit_net(struct net *net)
1048 {
1049 	proc_net_remove(net, "raw");
1050 }
1051 
1052 static __net_initdata struct pernet_operations raw_net_ops = {
1053 	.init = raw_init_net,
1054 	.exit = raw_exit_net,
1055 };
1056 
1057 int __init raw_proc_init(void)
1058 {
1059 	return register_pernet_subsys(&raw_net_ops);
1060 }
1061 
1062 void __init raw_proc_exit(void)
1063 {
1064 	unregister_pernet_subsys(&raw_net_ops);
1065 }
1066 #endif /* CONFIG_PROC_FS */
1067