xref: /linux/net/core/sock.c (revision a0f97e06a43cf524e616f09e6af3398e1e9c1c5b)
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  *		Generic socket support routines. Memory allocators, socket lock/release
7  *		handler for protocols to use and generic option handler.
8  *
9  *
10  * Version:	$Id: sock.c,v 1.117 2002/02/01 22:01:03 davem Exp $
11  *
12  * Authors:	Ross Biro
13  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
14  *		Florian La Roche, <flla@stud.uni-sb.de>
15  *		Alan Cox, <A.Cox@swansea.ac.uk>
16  *
17  * Fixes:
18  *		Alan Cox	: 	Numerous verify_area() problems
19  *		Alan Cox	:	Connecting on a connecting socket
20  *					now returns an error for tcp.
21  *		Alan Cox	:	sock->protocol is set correctly.
22  *					and is not sometimes left as 0.
23  *		Alan Cox	:	connect handles icmp errors on a
24  *					connect properly. Unfortunately there
25  *					is a restart syscall nasty there. I
26  *					can't match BSD without hacking the C
27  *					library. Ideas urgently sought!
28  *		Alan Cox	:	Disallow bind() to addresses that are
29  *					not ours - especially broadcast ones!!
30  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
31  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
32  *					instead they leave that for the DESTROY timer.
33  *		Alan Cox	:	Clean up error flag in accept
34  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
35  *					was buggy. Put a remove_sock() in the handler
36  *					for memory when we hit 0. Also altered the timer
37  *					code. The ACK stuff can wait and needs major
38  *					TCP layer surgery.
39  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
40  *					and fixed timer/inet_bh race.
41  *		Alan Cox	:	Added zapped flag for TCP
42  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
43  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
44  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
45  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
46  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
47  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
48  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
49  *	Pauline Middelink	:	identd support
50  *		Alan Cox	:	Fixed connect() taking signals I think.
51  *		Alan Cox	:	SO_LINGER supported
52  *		Alan Cox	:	Error reporting fixes
53  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
54  *		Alan Cox	:	inet sockets don't set sk->type!
55  *		Alan Cox	:	Split socket option code
56  *		Alan Cox	:	Callbacks
57  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
58  *		Alex		:	Removed restriction on inet fioctl
59  *		Alan Cox	:	Splitting INET from NET core
60  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
61  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
62  *		Alan Cox	:	Split IP from generic code
63  *		Alan Cox	:	New kfree_skbmem()
64  *		Alan Cox	:	Make SO_DEBUG superuser only.
65  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
66  *					(compatibility fix)
67  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
68  *		Alan Cox	:	Allocator for a socket is settable.
69  *		Alan Cox	:	SO_ERROR includes soft errors.
70  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
71  *		Alan Cox	: 	Generic socket allocation to make hooks
72  *					easier (suggested by Craig Metz).
73  *		Michael Pall	:	SO_ERROR returns positive errno again
74  *              Steve Whitehouse:       Added default destructor to free
75  *                                      protocol private data.
76  *              Steve Whitehouse:       Added various other default routines
77  *                                      common to several socket families.
78  *              Chris Evans     :       Call suser() check last on F_SETOWN
79  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
80  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
81  *		Andi Kleen	:	Fix write_space callback
82  *		Chris Evans	:	Security fixes - signedness again
83  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
84  *
85  * To Fix:
86  *
87  *
88  *		This program is free software; you can redistribute it and/or
89  *		modify it under the terms of the GNU General Public License
90  *		as published by the Free Software Foundation; either version
91  *		2 of the License, or (at your option) any later version.
92  */
93 
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/types.h>
97 #include <linux/socket.h>
98 #include <linux/in.h>
99 #include <linux/kernel.h>
100 #include <linux/module.h>
101 #include <linux/proc_fs.h>
102 #include <linux/seq_file.h>
103 #include <linux/sched.h>
104 #include <linux/timer.h>
105 #include <linux/string.h>
106 #include <linux/sockios.h>
107 #include <linux/net.h>
108 #include <linux/mm.h>
109 #include <linux/slab.h>
110 #include <linux/interrupt.h>
111 #include <linux/poll.h>
112 #include <linux/tcp.h>
113 #include <linux/init.h>
114 #include <linux/highmem.h>
115 
116 #include <asm/uaccess.h>
117 #include <asm/system.h>
118 
119 #include <linux/netdevice.h>
120 #include <net/protocol.h>
121 #include <linux/skbuff.h>
122 #include <net/net_namespace.h>
123 #include <net/request_sock.h>
124 #include <net/sock.h>
125 #include <net/xfrm.h>
126 #include <linux/ipsec.h>
127 
128 #include <linux/filter.h>
129 
130 #ifdef CONFIG_INET
131 #include <net/tcp.h>
132 #endif
133 
134 /*
135  * Each address family might have different locking rules, so we have
136  * one slock key per address family:
137  */
138 static struct lock_class_key af_family_keys[AF_MAX];
139 static struct lock_class_key af_family_slock_keys[AF_MAX];
140 
141 #ifdef CONFIG_DEBUG_LOCK_ALLOC
142 /*
143  * Make lock validator output more readable. (we pre-construct these
144  * strings build-time, so that runtime initialization of socket
145  * locks is fast):
146  */
147 static const char *af_family_key_strings[AF_MAX+1] = {
148   "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
149   "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
150   "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
151   "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
152   "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
153   "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
154   "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
155   "sk_lock-21"       , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
156   "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
157   "sk_lock-27"       , "sk_lock-28"          , "sk_lock-29"          ,
158   "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
159   "sk_lock-AF_RXRPC" , "sk_lock-AF_MAX"
160 };
161 static const char *af_family_slock_key_strings[AF_MAX+1] = {
162   "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
163   "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
164   "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
165   "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
166   "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
167   "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
168   "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
169   "slock-21"       , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
170   "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
171   "slock-27"       , "slock-28"          , "slock-29"          ,
172   "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
173   "slock-AF_RXRPC" , "slock-AF_MAX"
174 };
175 static const char *af_family_clock_key_strings[AF_MAX+1] = {
176   "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
177   "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
178   "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
179   "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
180   "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
181   "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
182   "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
183   "clock-21"       , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
184   "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
185   "clock-27"       , "clock-28"          , "clock-29"          ,
186   "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
187   "clock-AF_RXRPC" , "clock-AF_MAX"
188 };
189 #endif
190 
191 /*
192  * sk_callback_lock locking rules are per-address-family,
193  * so split the lock classes by using a per-AF key:
194  */
195 static struct lock_class_key af_callback_keys[AF_MAX];
196 
197 /* Take into consideration the size of the struct sk_buff overhead in the
198  * determination of these values, since that is non-constant across
199  * platforms.  This makes socket queueing behavior and performance
200  * not depend upon such differences.
201  */
202 #define _SK_MEM_PACKETS		256
203 #define _SK_MEM_OVERHEAD	(sizeof(struct sk_buff) + 256)
204 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
205 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
206 
207 /* Run time adjustable parameters. */
208 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
209 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
210 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
211 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
212 
213 /* Maximal space eaten by iovec or ancilliary data plus some space */
214 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
215 
216 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
217 {
218 	struct timeval tv;
219 
220 	if (optlen < sizeof(tv))
221 		return -EINVAL;
222 	if (copy_from_user(&tv, optval, sizeof(tv)))
223 		return -EFAULT;
224 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
225 		return -EDOM;
226 
227 	if (tv.tv_sec < 0) {
228 		static int warned __read_mostly;
229 
230 		*timeo_p = 0;
231 		if (warned < 10 && net_ratelimit())
232 			warned++;
233 			printk(KERN_INFO "sock_set_timeout: `%s' (pid %d) "
234 			       "tries to set negative timeout\n",
235 				current->comm, current->pid);
236 		return 0;
237 	}
238 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
239 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
240 		return 0;
241 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
242 		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
243 	return 0;
244 }
245 
246 static void sock_warn_obsolete_bsdism(const char *name)
247 {
248 	static int warned;
249 	static char warncomm[TASK_COMM_LEN];
250 	if (strcmp(warncomm, current->comm) && warned < 5) {
251 		strcpy(warncomm,  current->comm);
252 		printk(KERN_WARNING "process `%s' is using obsolete "
253 		       "%s SO_BSDCOMPAT\n", warncomm, name);
254 		warned++;
255 	}
256 }
257 
258 static void sock_disable_timestamp(struct sock *sk)
259 {
260 	if (sock_flag(sk, SOCK_TIMESTAMP)) {
261 		sock_reset_flag(sk, SOCK_TIMESTAMP);
262 		net_disable_timestamp();
263 	}
264 }
265 
266 
267 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
268 {
269 	int err = 0;
270 	int skb_len;
271 
272 	/* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
273 	   number of warnings when compiling with -W --ANK
274 	 */
275 	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
276 	    (unsigned)sk->sk_rcvbuf) {
277 		err = -ENOMEM;
278 		goto out;
279 	}
280 
281 	err = sk_filter(sk, skb);
282 	if (err)
283 		goto out;
284 
285 	skb->dev = NULL;
286 	skb_set_owner_r(skb, sk);
287 
288 	/* Cache the SKB length before we tack it onto the receive
289 	 * queue.  Once it is added it no longer belongs to us and
290 	 * may be freed by other threads of control pulling packets
291 	 * from the queue.
292 	 */
293 	skb_len = skb->len;
294 
295 	skb_queue_tail(&sk->sk_receive_queue, skb);
296 
297 	if (!sock_flag(sk, SOCK_DEAD))
298 		sk->sk_data_ready(sk, skb_len);
299 out:
300 	return err;
301 }
302 EXPORT_SYMBOL(sock_queue_rcv_skb);
303 
304 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
305 {
306 	int rc = NET_RX_SUCCESS;
307 
308 	if (sk_filter(sk, skb))
309 		goto discard_and_relse;
310 
311 	skb->dev = NULL;
312 
313 	if (nested)
314 		bh_lock_sock_nested(sk);
315 	else
316 		bh_lock_sock(sk);
317 	if (!sock_owned_by_user(sk)) {
318 		/*
319 		 * trylock + unlock semantics:
320 		 */
321 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
322 
323 		rc = sk->sk_backlog_rcv(sk, skb);
324 
325 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
326 	} else
327 		sk_add_backlog(sk, skb);
328 	bh_unlock_sock(sk);
329 out:
330 	sock_put(sk);
331 	return rc;
332 discard_and_relse:
333 	kfree_skb(skb);
334 	goto out;
335 }
336 EXPORT_SYMBOL(sk_receive_skb);
337 
338 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
339 {
340 	struct dst_entry *dst = sk->sk_dst_cache;
341 
342 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
343 		sk->sk_dst_cache = NULL;
344 		dst_release(dst);
345 		return NULL;
346 	}
347 
348 	return dst;
349 }
350 EXPORT_SYMBOL(__sk_dst_check);
351 
352 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
353 {
354 	struct dst_entry *dst = sk_dst_get(sk);
355 
356 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
357 		sk_dst_reset(sk);
358 		dst_release(dst);
359 		return NULL;
360 	}
361 
362 	return dst;
363 }
364 EXPORT_SYMBOL(sk_dst_check);
365 
366 static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
367 {
368 	int ret = -ENOPROTOOPT;
369 #ifdef CONFIG_NETDEVICES
370 	struct net *net = sk->sk_net;
371 	char devname[IFNAMSIZ];
372 	int index;
373 
374 	/* Sorry... */
375 	ret = -EPERM;
376 	if (!capable(CAP_NET_RAW))
377 		goto out;
378 
379 	ret = -EINVAL;
380 	if (optlen < 0)
381 		goto out;
382 
383 	/* Bind this socket to a particular device like "eth0",
384 	 * as specified in the passed interface name. If the
385 	 * name is "" or the option length is zero the socket
386 	 * is not bound.
387 	 */
388 	if (optlen > IFNAMSIZ - 1)
389 		optlen = IFNAMSIZ - 1;
390 	memset(devname, 0, sizeof(devname));
391 
392 	ret = -EFAULT;
393 	if (copy_from_user(devname, optval, optlen))
394 		goto out;
395 
396 	if (devname[0] == '\0') {
397 		index = 0;
398 	} else {
399 		struct net_device *dev = dev_get_by_name(net, devname);
400 
401 		ret = -ENODEV;
402 		if (!dev)
403 			goto out;
404 
405 		index = dev->ifindex;
406 		dev_put(dev);
407 	}
408 
409 	lock_sock(sk);
410 	sk->sk_bound_dev_if = index;
411 	sk_dst_reset(sk);
412 	release_sock(sk);
413 
414 	ret = 0;
415 
416 out:
417 #endif
418 
419 	return ret;
420 }
421 
422 /*
423  *	This is meant for all protocols to use and covers goings on
424  *	at the socket level. Everything here is generic.
425  */
426 
427 int sock_setsockopt(struct socket *sock, int level, int optname,
428 		    char __user *optval, int optlen)
429 {
430 	struct sock *sk=sock->sk;
431 	struct sk_filter *filter;
432 	int val;
433 	int valbool;
434 	struct linger ling;
435 	int ret = 0;
436 
437 	/*
438 	 *	Options without arguments
439 	 */
440 
441 #ifdef SO_DONTLINGER		/* Compatibility item... */
442 	if (optname == SO_DONTLINGER) {
443 		lock_sock(sk);
444 		sock_reset_flag(sk, SOCK_LINGER);
445 		release_sock(sk);
446 		return 0;
447 	}
448 #endif
449 
450 	if (optname == SO_BINDTODEVICE)
451 		return sock_bindtodevice(sk, optval, optlen);
452 
453 	if (optlen < sizeof(int))
454 		return -EINVAL;
455 
456 	if (get_user(val, (int __user *)optval))
457 		return -EFAULT;
458 
459 	valbool = val?1:0;
460 
461 	lock_sock(sk);
462 
463 	switch(optname) {
464 	case SO_DEBUG:
465 		if (val && !capable(CAP_NET_ADMIN)) {
466 			ret = -EACCES;
467 		}
468 		else if (valbool)
469 			sock_set_flag(sk, SOCK_DBG);
470 		else
471 			sock_reset_flag(sk, SOCK_DBG);
472 		break;
473 	case SO_REUSEADDR:
474 		sk->sk_reuse = valbool;
475 		break;
476 	case SO_TYPE:
477 	case SO_ERROR:
478 		ret = -ENOPROTOOPT;
479 		break;
480 	case SO_DONTROUTE:
481 		if (valbool)
482 			sock_set_flag(sk, SOCK_LOCALROUTE);
483 		else
484 			sock_reset_flag(sk, SOCK_LOCALROUTE);
485 		break;
486 	case SO_BROADCAST:
487 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
488 		break;
489 	case SO_SNDBUF:
490 		/* Don't error on this BSD doesn't and if you think
491 		   about it this is right. Otherwise apps have to
492 		   play 'guess the biggest size' games. RCVBUF/SNDBUF
493 		   are treated in BSD as hints */
494 
495 		if (val > sysctl_wmem_max)
496 			val = sysctl_wmem_max;
497 set_sndbuf:
498 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
499 		if ((val * 2) < SOCK_MIN_SNDBUF)
500 			sk->sk_sndbuf = SOCK_MIN_SNDBUF;
501 		else
502 			sk->sk_sndbuf = val * 2;
503 
504 		/*
505 		 *	Wake up sending tasks if we
506 		 *	upped the value.
507 		 */
508 		sk->sk_write_space(sk);
509 		break;
510 
511 	case SO_SNDBUFFORCE:
512 		if (!capable(CAP_NET_ADMIN)) {
513 			ret = -EPERM;
514 			break;
515 		}
516 		goto set_sndbuf;
517 
518 	case SO_RCVBUF:
519 		/* Don't error on this BSD doesn't and if you think
520 		   about it this is right. Otherwise apps have to
521 		   play 'guess the biggest size' games. RCVBUF/SNDBUF
522 		   are treated in BSD as hints */
523 
524 		if (val > sysctl_rmem_max)
525 			val = sysctl_rmem_max;
526 set_rcvbuf:
527 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
528 		/*
529 		 * We double it on the way in to account for
530 		 * "struct sk_buff" etc. overhead.   Applications
531 		 * assume that the SO_RCVBUF setting they make will
532 		 * allow that much actual data to be received on that
533 		 * socket.
534 		 *
535 		 * Applications are unaware that "struct sk_buff" and
536 		 * other overheads allocate from the receive buffer
537 		 * during socket buffer allocation.
538 		 *
539 		 * And after considering the possible alternatives,
540 		 * returning the value we actually used in getsockopt
541 		 * is the most desirable behavior.
542 		 */
543 		if ((val * 2) < SOCK_MIN_RCVBUF)
544 			sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
545 		else
546 			sk->sk_rcvbuf = val * 2;
547 		break;
548 
549 	case SO_RCVBUFFORCE:
550 		if (!capable(CAP_NET_ADMIN)) {
551 			ret = -EPERM;
552 			break;
553 		}
554 		goto set_rcvbuf;
555 
556 	case SO_KEEPALIVE:
557 #ifdef CONFIG_INET
558 		if (sk->sk_protocol == IPPROTO_TCP)
559 			tcp_set_keepalive(sk, valbool);
560 #endif
561 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
562 		break;
563 
564 	case SO_OOBINLINE:
565 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
566 		break;
567 
568 	case SO_NO_CHECK:
569 		sk->sk_no_check = valbool;
570 		break;
571 
572 	case SO_PRIORITY:
573 		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
574 			sk->sk_priority = val;
575 		else
576 			ret = -EPERM;
577 		break;
578 
579 	case SO_LINGER:
580 		if (optlen < sizeof(ling)) {
581 			ret = -EINVAL;	/* 1003.1g */
582 			break;
583 		}
584 		if (copy_from_user(&ling,optval,sizeof(ling))) {
585 			ret = -EFAULT;
586 			break;
587 		}
588 		if (!ling.l_onoff)
589 			sock_reset_flag(sk, SOCK_LINGER);
590 		else {
591 #if (BITS_PER_LONG == 32)
592 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
593 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
594 			else
595 #endif
596 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
597 			sock_set_flag(sk, SOCK_LINGER);
598 		}
599 		break;
600 
601 	case SO_BSDCOMPAT:
602 		sock_warn_obsolete_bsdism("setsockopt");
603 		break;
604 
605 	case SO_PASSCRED:
606 		if (valbool)
607 			set_bit(SOCK_PASSCRED, &sock->flags);
608 		else
609 			clear_bit(SOCK_PASSCRED, &sock->flags);
610 		break;
611 
612 	case SO_TIMESTAMP:
613 	case SO_TIMESTAMPNS:
614 		if (valbool)  {
615 			if (optname == SO_TIMESTAMP)
616 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
617 			else
618 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
619 			sock_set_flag(sk, SOCK_RCVTSTAMP);
620 			sock_enable_timestamp(sk);
621 		} else {
622 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
623 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
624 		}
625 		break;
626 
627 	case SO_RCVLOWAT:
628 		if (val < 0)
629 			val = INT_MAX;
630 		sk->sk_rcvlowat = val ? : 1;
631 		break;
632 
633 	case SO_RCVTIMEO:
634 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
635 		break;
636 
637 	case SO_SNDTIMEO:
638 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
639 		break;
640 
641 	case SO_ATTACH_FILTER:
642 		ret = -EINVAL;
643 		if (optlen == sizeof(struct sock_fprog)) {
644 			struct sock_fprog fprog;
645 
646 			ret = -EFAULT;
647 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
648 				break;
649 
650 			ret = sk_attach_filter(&fprog, sk);
651 		}
652 		break;
653 
654 	case SO_DETACH_FILTER:
655 		rcu_read_lock_bh();
656 		filter = rcu_dereference(sk->sk_filter);
657 		if (filter) {
658 			rcu_assign_pointer(sk->sk_filter, NULL);
659 			sk_filter_release(sk, filter);
660 			rcu_read_unlock_bh();
661 			break;
662 		}
663 		rcu_read_unlock_bh();
664 		ret = -ENONET;
665 		break;
666 
667 	case SO_PASSSEC:
668 		if (valbool)
669 			set_bit(SOCK_PASSSEC, &sock->flags);
670 		else
671 			clear_bit(SOCK_PASSSEC, &sock->flags);
672 		break;
673 
674 		/* We implement the SO_SNDLOWAT etc to
675 		   not be settable (1003.1g 5.3) */
676 	default:
677 		ret = -ENOPROTOOPT;
678 		break;
679 	}
680 	release_sock(sk);
681 	return ret;
682 }
683 
684 
685 int sock_getsockopt(struct socket *sock, int level, int optname,
686 		    char __user *optval, int __user *optlen)
687 {
688 	struct sock *sk = sock->sk;
689 
690 	union {
691 		int val;
692 		struct linger ling;
693 		struct timeval tm;
694 	} v;
695 
696 	unsigned int lv = sizeof(int);
697 	int len;
698 
699 	if (get_user(len, optlen))
700 		return -EFAULT;
701 	if (len < 0)
702 		return -EINVAL;
703 
704 	switch(optname) {
705 	case SO_DEBUG:
706 		v.val = sock_flag(sk, SOCK_DBG);
707 		break;
708 
709 	case SO_DONTROUTE:
710 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
711 		break;
712 
713 	case SO_BROADCAST:
714 		v.val = !!sock_flag(sk, SOCK_BROADCAST);
715 		break;
716 
717 	case SO_SNDBUF:
718 		v.val = sk->sk_sndbuf;
719 		break;
720 
721 	case SO_RCVBUF:
722 		v.val = sk->sk_rcvbuf;
723 		break;
724 
725 	case SO_REUSEADDR:
726 		v.val = sk->sk_reuse;
727 		break;
728 
729 	case SO_KEEPALIVE:
730 		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
731 		break;
732 
733 	case SO_TYPE:
734 		v.val = sk->sk_type;
735 		break;
736 
737 	case SO_ERROR:
738 		v.val = -sock_error(sk);
739 		if (v.val==0)
740 			v.val = xchg(&sk->sk_err_soft, 0);
741 		break;
742 
743 	case SO_OOBINLINE:
744 		v.val = !!sock_flag(sk, SOCK_URGINLINE);
745 		break;
746 
747 	case SO_NO_CHECK:
748 		v.val = sk->sk_no_check;
749 		break;
750 
751 	case SO_PRIORITY:
752 		v.val = sk->sk_priority;
753 		break;
754 
755 	case SO_LINGER:
756 		lv		= sizeof(v.ling);
757 		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
758 		v.ling.l_linger	= sk->sk_lingertime / HZ;
759 		break;
760 
761 	case SO_BSDCOMPAT:
762 		sock_warn_obsolete_bsdism("getsockopt");
763 		break;
764 
765 	case SO_TIMESTAMP:
766 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
767 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
768 		break;
769 
770 	case SO_TIMESTAMPNS:
771 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
772 		break;
773 
774 	case SO_RCVTIMEO:
775 		lv=sizeof(struct timeval);
776 		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
777 			v.tm.tv_sec = 0;
778 			v.tm.tv_usec = 0;
779 		} else {
780 			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
781 			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
782 		}
783 		break;
784 
785 	case SO_SNDTIMEO:
786 		lv=sizeof(struct timeval);
787 		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
788 			v.tm.tv_sec = 0;
789 			v.tm.tv_usec = 0;
790 		} else {
791 			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
792 			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
793 		}
794 		break;
795 
796 	case SO_RCVLOWAT:
797 		v.val = sk->sk_rcvlowat;
798 		break;
799 
800 	case SO_SNDLOWAT:
801 		v.val=1;
802 		break;
803 
804 	case SO_PASSCRED:
805 		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
806 		break;
807 
808 	case SO_PEERCRED:
809 		if (len > sizeof(sk->sk_peercred))
810 			len = sizeof(sk->sk_peercred);
811 		if (copy_to_user(optval, &sk->sk_peercred, len))
812 			return -EFAULT;
813 		goto lenout;
814 
815 	case SO_PEERNAME:
816 	{
817 		char address[128];
818 
819 		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
820 			return -ENOTCONN;
821 		if (lv < len)
822 			return -EINVAL;
823 		if (copy_to_user(optval, address, len))
824 			return -EFAULT;
825 		goto lenout;
826 	}
827 
828 	/* Dubious BSD thing... Probably nobody even uses it, but
829 	 * the UNIX standard wants it for whatever reason... -DaveM
830 	 */
831 	case SO_ACCEPTCONN:
832 		v.val = sk->sk_state == TCP_LISTEN;
833 		break;
834 
835 	case SO_PASSSEC:
836 		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
837 		break;
838 
839 	case SO_PEERSEC:
840 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
841 
842 	default:
843 		return -ENOPROTOOPT;
844 	}
845 
846 	if (len > lv)
847 		len = lv;
848 	if (copy_to_user(optval, &v, len))
849 		return -EFAULT;
850 lenout:
851 	if (put_user(len, optlen))
852 		return -EFAULT;
853 	return 0;
854 }
855 
856 /*
857  * Initialize an sk_lock.
858  *
859  * (We also register the sk_lock with the lock validator.)
860  */
861 static inline void sock_lock_init(struct sock *sk)
862 {
863 	sock_lock_init_class_and_name(sk,
864 			af_family_slock_key_strings[sk->sk_family],
865 			af_family_slock_keys + sk->sk_family,
866 			af_family_key_strings[sk->sk_family],
867 			af_family_keys + sk->sk_family);
868 }
869 
870 /**
871  *	sk_alloc - All socket objects are allocated here
872  *	@family: protocol family
873  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
874  *	@prot: struct proto associated with this new sock instance
875  *	@zero_it: if we should zero the newly allocated sock
876  */
877 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
878 		      struct proto *prot, int zero_it)
879 {
880 	struct sock *sk = NULL;
881 	struct kmem_cache *slab = prot->slab;
882 
883 	if (slab != NULL)
884 		sk = kmem_cache_alloc(slab, priority);
885 	else
886 		sk = kmalloc(prot->obj_size, priority);
887 
888 	if (sk) {
889 		if (zero_it) {
890 			memset(sk, 0, prot->obj_size);
891 			sk->sk_family = family;
892 			/*
893 			 * See comment in struct sock definition to understand
894 			 * why we need sk_prot_creator -acme
895 			 */
896 			sk->sk_prot = sk->sk_prot_creator = prot;
897 			sock_lock_init(sk);
898 			sk->sk_net = get_net(net);
899 		}
900 
901 		if (security_sk_alloc(sk, family, priority))
902 			goto out_free;
903 
904 		if (!try_module_get(prot->owner))
905 			goto out_free;
906 	}
907 	return sk;
908 
909 out_free:
910 	if (slab != NULL)
911 		kmem_cache_free(slab, sk);
912 	else
913 		kfree(sk);
914 	return NULL;
915 }
916 
917 void sk_free(struct sock *sk)
918 {
919 	struct sk_filter *filter;
920 	struct module *owner = sk->sk_prot_creator->owner;
921 
922 	if (sk->sk_destruct)
923 		sk->sk_destruct(sk);
924 
925 	filter = rcu_dereference(sk->sk_filter);
926 	if (filter) {
927 		sk_filter_release(sk, filter);
928 		rcu_assign_pointer(sk->sk_filter, NULL);
929 	}
930 
931 	sock_disable_timestamp(sk);
932 
933 	if (atomic_read(&sk->sk_omem_alloc))
934 		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
935 		       __FUNCTION__, atomic_read(&sk->sk_omem_alloc));
936 
937 	security_sk_free(sk);
938 	put_net(sk->sk_net);
939 	if (sk->sk_prot_creator->slab != NULL)
940 		kmem_cache_free(sk->sk_prot_creator->slab, sk);
941 	else
942 		kfree(sk);
943 	module_put(owner);
944 }
945 
946 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
947 {
948 	struct sock *newsk = sk_alloc(sk->sk_net, sk->sk_family, priority, sk->sk_prot, 0);
949 
950 	if (newsk != NULL) {
951 		struct sk_filter *filter;
952 
953 		sock_copy(newsk, sk);
954 
955 		/* SANITY */
956 		sk_node_init(&newsk->sk_node);
957 		sock_lock_init(newsk);
958 		bh_lock_sock(newsk);
959 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
960 
961 		atomic_set(&newsk->sk_rmem_alloc, 0);
962 		atomic_set(&newsk->sk_wmem_alloc, 0);
963 		atomic_set(&newsk->sk_omem_alloc, 0);
964 		skb_queue_head_init(&newsk->sk_receive_queue);
965 		skb_queue_head_init(&newsk->sk_write_queue);
966 #ifdef CONFIG_NET_DMA
967 		skb_queue_head_init(&newsk->sk_async_wait_queue);
968 #endif
969 
970 		rwlock_init(&newsk->sk_dst_lock);
971 		rwlock_init(&newsk->sk_callback_lock);
972 		lockdep_set_class_and_name(&newsk->sk_callback_lock,
973 				af_callback_keys + newsk->sk_family,
974 				af_family_clock_key_strings[newsk->sk_family]);
975 
976 		newsk->sk_dst_cache	= NULL;
977 		newsk->sk_wmem_queued	= 0;
978 		newsk->sk_forward_alloc = 0;
979 		newsk->sk_send_head	= NULL;
980 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
981 
982 		sock_reset_flag(newsk, SOCK_DONE);
983 		skb_queue_head_init(&newsk->sk_error_queue);
984 
985 		filter = newsk->sk_filter;
986 		if (filter != NULL)
987 			sk_filter_charge(newsk, filter);
988 
989 		if (unlikely(xfrm_sk_clone_policy(newsk))) {
990 			/* It is still raw copy of parent, so invalidate
991 			 * destructor and make plain sk_free() */
992 			newsk->sk_destruct = NULL;
993 			sk_free(newsk);
994 			newsk = NULL;
995 			goto out;
996 		}
997 
998 		newsk->sk_err	   = 0;
999 		newsk->sk_priority = 0;
1000 		atomic_set(&newsk->sk_refcnt, 2);
1001 
1002 		/*
1003 		 * Increment the counter in the same struct proto as the master
1004 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1005 		 * is the same as sk->sk_prot->socks, as this field was copied
1006 		 * with memcpy).
1007 		 *
1008 		 * This _changes_ the previous behaviour, where
1009 		 * tcp_create_openreq_child always was incrementing the
1010 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1011 		 * to be taken into account in all callers. -acme
1012 		 */
1013 		sk_refcnt_debug_inc(newsk);
1014 		newsk->sk_socket = NULL;
1015 		newsk->sk_sleep	 = NULL;
1016 
1017 		if (newsk->sk_prot->sockets_allocated)
1018 			atomic_inc(newsk->sk_prot->sockets_allocated);
1019 	}
1020 out:
1021 	return newsk;
1022 }
1023 
1024 EXPORT_SYMBOL_GPL(sk_clone);
1025 
1026 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1027 {
1028 	__sk_dst_set(sk, dst);
1029 	sk->sk_route_caps = dst->dev->features;
1030 	if (sk->sk_route_caps & NETIF_F_GSO)
1031 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1032 	if (sk_can_gso(sk)) {
1033 		if (dst->header_len)
1034 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1035 		else
1036 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1037 	}
1038 }
1039 EXPORT_SYMBOL_GPL(sk_setup_caps);
1040 
1041 void __init sk_init(void)
1042 {
1043 	if (num_physpages <= 4096) {
1044 		sysctl_wmem_max = 32767;
1045 		sysctl_rmem_max = 32767;
1046 		sysctl_wmem_default = 32767;
1047 		sysctl_rmem_default = 32767;
1048 	} else if (num_physpages >= 131072) {
1049 		sysctl_wmem_max = 131071;
1050 		sysctl_rmem_max = 131071;
1051 	}
1052 }
1053 
1054 /*
1055  *	Simple resource managers for sockets.
1056  */
1057 
1058 
1059 /*
1060  * Write buffer destructor automatically called from kfree_skb.
1061  */
1062 void sock_wfree(struct sk_buff *skb)
1063 {
1064 	struct sock *sk = skb->sk;
1065 
1066 	/* In case it might be waiting for more memory. */
1067 	atomic_sub(skb->truesize, &sk->sk_wmem_alloc);
1068 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE))
1069 		sk->sk_write_space(sk);
1070 	sock_put(sk);
1071 }
1072 
1073 /*
1074  * Read buffer destructor automatically called from kfree_skb.
1075  */
1076 void sock_rfree(struct sk_buff *skb)
1077 {
1078 	struct sock *sk = skb->sk;
1079 
1080 	atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
1081 }
1082 
1083 
1084 int sock_i_uid(struct sock *sk)
1085 {
1086 	int uid;
1087 
1088 	read_lock(&sk->sk_callback_lock);
1089 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1090 	read_unlock(&sk->sk_callback_lock);
1091 	return uid;
1092 }
1093 
1094 unsigned long sock_i_ino(struct sock *sk)
1095 {
1096 	unsigned long ino;
1097 
1098 	read_lock(&sk->sk_callback_lock);
1099 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1100 	read_unlock(&sk->sk_callback_lock);
1101 	return ino;
1102 }
1103 
1104 /*
1105  * Allocate a skb from the socket's send buffer.
1106  */
1107 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1108 			     gfp_t priority)
1109 {
1110 	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1111 		struct sk_buff * skb = alloc_skb(size, priority);
1112 		if (skb) {
1113 			skb_set_owner_w(skb, sk);
1114 			return skb;
1115 		}
1116 	}
1117 	return NULL;
1118 }
1119 
1120 /*
1121  * Allocate a skb from the socket's receive buffer.
1122  */
1123 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1124 			     gfp_t priority)
1125 {
1126 	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1127 		struct sk_buff *skb = alloc_skb(size, priority);
1128 		if (skb) {
1129 			skb_set_owner_r(skb, sk);
1130 			return skb;
1131 		}
1132 	}
1133 	return NULL;
1134 }
1135 
1136 /*
1137  * Allocate a memory block from the socket's option memory buffer.
1138  */
1139 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1140 {
1141 	if ((unsigned)size <= sysctl_optmem_max &&
1142 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1143 		void *mem;
1144 		/* First do the add, to avoid the race if kmalloc
1145 		 * might sleep.
1146 		 */
1147 		atomic_add(size, &sk->sk_omem_alloc);
1148 		mem = kmalloc(size, priority);
1149 		if (mem)
1150 			return mem;
1151 		atomic_sub(size, &sk->sk_omem_alloc);
1152 	}
1153 	return NULL;
1154 }
1155 
1156 /*
1157  * Free an option memory block.
1158  */
1159 void sock_kfree_s(struct sock *sk, void *mem, int size)
1160 {
1161 	kfree(mem);
1162 	atomic_sub(size, &sk->sk_omem_alloc);
1163 }
1164 
1165 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1166    I think, these locks should be removed for datagram sockets.
1167  */
1168 static long sock_wait_for_wmem(struct sock * sk, long timeo)
1169 {
1170 	DEFINE_WAIT(wait);
1171 
1172 	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1173 	for (;;) {
1174 		if (!timeo)
1175 			break;
1176 		if (signal_pending(current))
1177 			break;
1178 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1179 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
1180 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1181 			break;
1182 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1183 			break;
1184 		if (sk->sk_err)
1185 			break;
1186 		timeo = schedule_timeout(timeo);
1187 	}
1188 	finish_wait(sk->sk_sleep, &wait);
1189 	return timeo;
1190 }
1191 
1192 
1193 /*
1194  *	Generic send/receive buffer handlers
1195  */
1196 
1197 static struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1198 					    unsigned long header_len,
1199 					    unsigned long data_len,
1200 					    int noblock, int *errcode)
1201 {
1202 	struct sk_buff *skb;
1203 	gfp_t gfp_mask;
1204 	long timeo;
1205 	int err;
1206 
1207 	gfp_mask = sk->sk_allocation;
1208 	if (gfp_mask & __GFP_WAIT)
1209 		gfp_mask |= __GFP_REPEAT;
1210 
1211 	timeo = sock_sndtimeo(sk, noblock);
1212 	while (1) {
1213 		err = sock_error(sk);
1214 		if (err != 0)
1215 			goto failure;
1216 
1217 		err = -EPIPE;
1218 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1219 			goto failure;
1220 
1221 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1222 			skb = alloc_skb(header_len, gfp_mask);
1223 			if (skb) {
1224 				int npages;
1225 				int i;
1226 
1227 				/* No pages, we're done... */
1228 				if (!data_len)
1229 					break;
1230 
1231 				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1232 				skb->truesize += data_len;
1233 				skb_shinfo(skb)->nr_frags = npages;
1234 				for (i = 0; i < npages; i++) {
1235 					struct page *page;
1236 					skb_frag_t *frag;
1237 
1238 					page = alloc_pages(sk->sk_allocation, 0);
1239 					if (!page) {
1240 						err = -ENOBUFS;
1241 						skb_shinfo(skb)->nr_frags = i;
1242 						kfree_skb(skb);
1243 						goto failure;
1244 					}
1245 
1246 					frag = &skb_shinfo(skb)->frags[i];
1247 					frag->page = page;
1248 					frag->page_offset = 0;
1249 					frag->size = (data_len >= PAGE_SIZE ?
1250 						      PAGE_SIZE :
1251 						      data_len);
1252 					data_len -= PAGE_SIZE;
1253 				}
1254 
1255 				/* Full success... */
1256 				break;
1257 			}
1258 			err = -ENOBUFS;
1259 			goto failure;
1260 		}
1261 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1262 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1263 		err = -EAGAIN;
1264 		if (!timeo)
1265 			goto failure;
1266 		if (signal_pending(current))
1267 			goto interrupted;
1268 		timeo = sock_wait_for_wmem(sk, timeo);
1269 	}
1270 
1271 	skb_set_owner_w(skb, sk);
1272 	return skb;
1273 
1274 interrupted:
1275 	err = sock_intr_errno(timeo);
1276 failure:
1277 	*errcode = err;
1278 	return NULL;
1279 }
1280 
1281 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1282 				    int noblock, int *errcode)
1283 {
1284 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1285 }
1286 
1287 static void __lock_sock(struct sock *sk)
1288 {
1289 	DEFINE_WAIT(wait);
1290 
1291 	for (;;) {
1292 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1293 					TASK_UNINTERRUPTIBLE);
1294 		spin_unlock_bh(&sk->sk_lock.slock);
1295 		schedule();
1296 		spin_lock_bh(&sk->sk_lock.slock);
1297 		if (!sock_owned_by_user(sk))
1298 			break;
1299 	}
1300 	finish_wait(&sk->sk_lock.wq, &wait);
1301 }
1302 
1303 static void __release_sock(struct sock *sk)
1304 {
1305 	struct sk_buff *skb = sk->sk_backlog.head;
1306 
1307 	do {
1308 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1309 		bh_unlock_sock(sk);
1310 
1311 		do {
1312 			struct sk_buff *next = skb->next;
1313 
1314 			skb->next = NULL;
1315 			sk->sk_backlog_rcv(sk, skb);
1316 
1317 			/*
1318 			 * We are in process context here with softirqs
1319 			 * disabled, use cond_resched_softirq() to preempt.
1320 			 * This is safe to do because we've taken the backlog
1321 			 * queue private:
1322 			 */
1323 			cond_resched_softirq();
1324 
1325 			skb = next;
1326 		} while (skb != NULL);
1327 
1328 		bh_lock_sock(sk);
1329 	} while ((skb = sk->sk_backlog.head) != NULL);
1330 }
1331 
1332 /**
1333  * sk_wait_data - wait for data to arrive at sk_receive_queue
1334  * @sk:    sock to wait on
1335  * @timeo: for how long
1336  *
1337  * Now socket state including sk->sk_err is changed only under lock,
1338  * hence we may omit checks after joining wait queue.
1339  * We check receive queue before schedule() only as optimization;
1340  * it is very likely that release_sock() added new data.
1341  */
1342 int sk_wait_data(struct sock *sk, long *timeo)
1343 {
1344 	int rc;
1345 	DEFINE_WAIT(wait);
1346 
1347 	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
1348 	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1349 	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1350 	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1351 	finish_wait(sk->sk_sleep, &wait);
1352 	return rc;
1353 }
1354 
1355 EXPORT_SYMBOL(sk_wait_data);
1356 
1357 /*
1358  * Set of default routines for initialising struct proto_ops when
1359  * the protocol does not support a particular function. In certain
1360  * cases where it makes no sense for a protocol to have a "do nothing"
1361  * function, some default processing is provided.
1362  */
1363 
1364 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1365 {
1366 	return -EOPNOTSUPP;
1367 }
1368 
1369 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1370 		    int len, int flags)
1371 {
1372 	return -EOPNOTSUPP;
1373 }
1374 
1375 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1376 {
1377 	return -EOPNOTSUPP;
1378 }
1379 
1380 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1381 {
1382 	return -EOPNOTSUPP;
1383 }
1384 
1385 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1386 		    int *len, int peer)
1387 {
1388 	return -EOPNOTSUPP;
1389 }
1390 
1391 unsigned int sock_no_poll(struct file * file, struct socket *sock, poll_table *pt)
1392 {
1393 	return 0;
1394 }
1395 
1396 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1397 {
1398 	return -EOPNOTSUPP;
1399 }
1400 
1401 int sock_no_listen(struct socket *sock, int backlog)
1402 {
1403 	return -EOPNOTSUPP;
1404 }
1405 
1406 int sock_no_shutdown(struct socket *sock, int how)
1407 {
1408 	return -EOPNOTSUPP;
1409 }
1410 
1411 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1412 		    char __user *optval, int optlen)
1413 {
1414 	return -EOPNOTSUPP;
1415 }
1416 
1417 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1418 		    char __user *optval, int __user *optlen)
1419 {
1420 	return -EOPNOTSUPP;
1421 }
1422 
1423 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1424 		    size_t len)
1425 {
1426 	return -EOPNOTSUPP;
1427 }
1428 
1429 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1430 		    size_t len, int flags)
1431 {
1432 	return -EOPNOTSUPP;
1433 }
1434 
1435 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1436 {
1437 	/* Mirror missing mmap method error code */
1438 	return -ENODEV;
1439 }
1440 
1441 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1442 {
1443 	ssize_t res;
1444 	struct msghdr msg = {.msg_flags = flags};
1445 	struct kvec iov;
1446 	char *kaddr = kmap(page);
1447 	iov.iov_base = kaddr + offset;
1448 	iov.iov_len = size;
1449 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1450 	kunmap(page);
1451 	return res;
1452 }
1453 
1454 /*
1455  *	Default Socket Callbacks
1456  */
1457 
1458 static void sock_def_wakeup(struct sock *sk)
1459 {
1460 	read_lock(&sk->sk_callback_lock);
1461 	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1462 		wake_up_interruptible_all(sk->sk_sleep);
1463 	read_unlock(&sk->sk_callback_lock);
1464 }
1465 
1466 static void sock_def_error_report(struct sock *sk)
1467 {
1468 	read_lock(&sk->sk_callback_lock);
1469 	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1470 		wake_up_interruptible(sk->sk_sleep);
1471 	sk_wake_async(sk,0,POLL_ERR);
1472 	read_unlock(&sk->sk_callback_lock);
1473 }
1474 
1475 static void sock_def_readable(struct sock *sk, int len)
1476 {
1477 	read_lock(&sk->sk_callback_lock);
1478 	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1479 		wake_up_interruptible(sk->sk_sleep);
1480 	sk_wake_async(sk,1,POLL_IN);
1481 	read_unlock(&sk->sk_callback_lock);
1482 }
1483 
1484 static void sock_def_write_space(struct sock *sk)
1485 {
1486 	read_lock(&sk->sk_callback_lock);
1487 
1488 	/* Do not wake up a writer until he can make "significant"
1489 	 * progress.  --DaveM
1490 	 */
1491 	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1492 		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1493 			wake_up_interruptible(sk->sk_sleep);
1494 
1495 		/* Should agree with poll, otherwise some programs break */
1496 		if (sock_writeable(sk))
1497 			sk_wake_async(sk, 2, POLL_OUT);
1498 	}
1499 
1500 	read_unlock(&sk->sk_callback_lock);
1501 }
1502 
1503 static void sock_def_destruct(struct sock *sk)
1504 {
1505 	kfree(sk->sk_protinfo);
1506 }
1507 
1508 void sk_send_sigurg(struct sock *sk)
1509 {
1510 	if (sk->sk_socket && sk->sk_socket->file)
1511 		if (send_sigurg(&sk->sk_socket->file->f_owner))
1512 			sk_wake_async(sk, 3, POLL_PRI);
1513 }
1514 
1515 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1516 		    unsigned long expires)
1517 {
1518 	if (!mod_timer(timer, expires))
1519 		sock_hold(sk);
1520 }
1521 
1522 EXPORT_SYMBOL(sk_reset_timer);
1523 
1524 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1525 {
1526 	if (timer_pending(timer) && del_timer(timer))
1527 		__sock_put(sk);
1528 }
1529 
1530 EXPORT_SYMBOL(sk_stop_timer);
1531 
1532 void sock_init_data(struct socket *sock, struct sock *sk)
1533 {
1534 	skb_queue_head_init(&sk->sk_receive_queue);
1535 	skb_queue_head_init(&sk->sk_write_queue);
1536 	skb_queue_head_init(&sk->sk_error_queue);
1537 #ifdef CONFIG_NET_DMA
1538 	skb_queue_head_init(&sk->sk_async_wait_queue);
1539 #endif
1540 
1541 	sk->sk_send_head	=	NULL;
1542 
1543 	init_timer(&sk->sk_timer);
1544 
1545 	sk->sk_allocation	=	GFP_KERNEL;
1546 	sk->sk_rcvbuf		=	sysctl_rmem_default;
1547 	sk->sk_sndbuf		=	sysctl_wmem_default;
1548 	sk->sk_state		=	TCP_CLOSE;
1549 	sk->sk_socket		=	sock;
1550 
1551 	sock_set_flag(sk, SOCK_ZAPPED);
1552 
1553 	if (sock) {
1554 		sk->sk_type	=	sock->type;
1555 		sk->sk_sleep	=	&sock->wait;
1556 		sock->sk	=	sk;
1557 	} else
1558 		sk->sk_sleep	=	NULL;
1559 
1560 	rwlock_init(&sk->sk_dst_lock);
1561 	rwlock_init(&sk->sk_callback_lock);
1562 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1563 			af_callback_keys + sk->sk_family,
1564 			af_family_clock_key_strings[sk->sk_family]);
1565 
1566 	sk->sk_state_change	=	sock_def_wakeup;
1567 	sk->sk_data_ready	=	sock_def_readable;
1568 	sk->sk_write_space	=	sock_def_write_space;
1569 	sk->sk_error_report	=	sock_def_error_report;
1570 	sk->sk_destruct		=	sock_def_destruct;
1571 
1572 	sk->sk_sndmsg_page	=	NULL;
1573 	sk->sk_sndmsg_off	=	0;
1574 
1575 	sk->sk_peercred.pid 	=	0;
1576 	sk->sk_peercred.uid	=	-1;
1577 	sk->sk_peercred.gid	=	-1;
1578 	sk->sk_write_pending	=	0;
1579 	sk->sk_rcvlowat		=	1;
1580 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
1581 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
1582 
1583 	sk->sk_stamp = ktime_set(-1L, -1L);
1584 
1585 	atomic_set(&sk->sk_refcnt, 1);
1586 }
1587 
1588 void fastcall lock_sock_nested(struct sock *sk, int subclass)
1589 {
1590 	might_sleep();
1591 	spin_lock_bh(&sk->sk_lock.slock);
1592 	if (sk->sk_lock.owned)
1593 		__lock_sock(sk);
1594 	sk->sk_lock.owned = 1;
1595 	spin_unlock(&sk->sk_lock.slock);
1596 	/*
1597 	 * The sk_lock has mutex_lock() semantics here:
1598 	 */
1599 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
1600 	local_bh_enable();
1601 }
1602 
1603 EXPORT_SYMBOL(lock_sock_nested);
1604 
1605 void fastcall release_sock(struct sock *sk)
1606 {
1607 	/*
1608 	 * The sk_lock has mutex_unlock() semantics:
1609 	 */
1610 	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1611 
1612 	spin_lock_bh(&sk->sk_lock.slock);
1613 	if (sk->sk_backlog.tail)
1614 		__release_sock(sk);
1615 	sk->sk_lock.owned = 0;
1616 	if (waitqueue_active(&sk->sk_lock.wq))
1617 		wake_up(&sk->sk_lock.wq);
1618 	spin_unlock_bh(&sk->sk_lock.slock);
1619 }
1620 EXPORT_SYMBOL(release_sock);
1621 
1622 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
1623 {
1624 	struct timeval tv;
1625 	if (!sock_flag(sk, SOCK_TIMESTAMP))
1626 		sock_enable_timestamp(sk);
1627 	tv = ktime_to_timeval(sk->sk_stamp);
1628 	if (tv.tv_sec == -1)
1629 		return -ENOENT;
1630 	if (tv.tv_sec == 0) {
1631 		sk->sk_stamp = ktime_get_real();
1632 		tv = ktime_to_timeval(sk->sk_stamp);
1633 	}
1634 	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
1635 }
1636 EXPORT_SYMBOL(sock_get_timestamp);
1637 
1638 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
1639 {
1640 	struct timespec ts;
1641 	if (!sock_flag(sk, SOCK_TIMESTAMP))
1642 		sock_enable_timestamp(sk);
1643 	ts = ktime_to_timespec(sk->sk_stamp);
1644 	if (ts.tv_sec == -1)
1645 		return -ENOENT;
1646 	if (ts.tv_sec == 0) {
1647 		sk->sk_stamp = ktime_get_real();
1648 		ts = ktime_to_timespec(sk->sk_stamp);
1649 	}
1650 	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
1651 }
1652 EXPORT_SYMBOL(sock_get_timestampns);
1653 
1654 void sock_enable_timestamp(struct sock *sk)
1655 {
1656 	if (!sock_flag(sk, SOCK_TIMESTAMP)) {
1657 		sock_set_flag(sk, SOCK_TIMESTAMP);
1658 		net_enable_timestamp();
1659 	}
1660 }
1661 EXPORT_SYMBOL(sock_enable_timestamp);
1662 
1663 /*
1664  *	Get a socket option on an socket.
1665  *
1666  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
1667  *	asynchronous errors should be reported by getsockopt. We assume
1668  *	this means if you specify SO_ERROR (otherwise whats the point of it).
1669  */
1670 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1671 			   char __user *optval, int __user *optlen)
1672 {
1673 	struct sock *sk = sock->sk;
1674 
1675 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1676 }
1677 
1678 EXPORT_SYMBOL(sock_common_getsockopt);
1679 
1680 #ifdef CONFIG_COMPAT
1681 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
1682 				  char __user *optval, int __user *optlen)
1683 {
1684 	struct sock *sk = sock->sk;
1685 
1686 	if (sk->sk_prot->compat_getsockopt != NULL)
1687 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
1688 						      optval, optlen);
1689 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1690 }
1691 EXPORT_SYMBOL(compat_sock_common_getsockopt);
1692 #endif
1693 
1694 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1695 			struct msghdr *msg, size_t size, int flags)
1696 {
1697 	struct sock *sk = sock->sk;
1698 	int addr_len = 0;
1699 	int err;
1700 
1701 	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
1702 				   flags & ~MSG_DONTWAIT, &addr_len);
1703 	if (err >= 0)
1704 		msg->msg_namelen = addr_len;
1705 	return err;
1706 }
1707 
1708 EXPORT_SYMBOL(sock_common_recvmsg);
1709 
1710 /*
1711  *	Set socket options on an inet socket.
1712  */
1713 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1714 			   char __user *optval, int optlen)
1715 {
1716 	struct sock *sk = sock->sk;
1717 
1718 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1719 }
1720 
1721 EXPORT_SYMBOL(sock_common_setsockopt);
1722 
1723 #ifdef CONFIG_COMPAT
1724 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
1725 				  char __user *optval, int optlen)
1726 {
1727 	struct sock *sk = sock->sk;
1728 
1729 	if (sk->sk_prot->compat_setsockopt != NULL)
1730 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
1731 						      optval, optlen);
1732 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1733 }
1734 EXPORT_SYMBOL(compat_sock_common_setsockopt);
1735 #endif
1736 
1737 void sk_common_release(struct sock *sk)
1738 {
1739 	if (sk->sk_prot->destroy)
1740 		sk->sk_prot->destroy(sk);
1741 
1742 	/*
1743 	 * Observation: when sock_common_release is called, processes have
1744 	 * no access to socket. But net still has.
1745 	 * Step one, detach it from networking:
1746 	 *
1747 	 * A. Remove from hash tables.
1748 	 */
1749 
1750 	sk->sk_prot->unhash(sk);
1751 
1752 	/*
1753 	 * In this point socket cannot receive new packets, but it is possible
1754 	 * that some packets are in flight because some CPU runs receiver and
1755 	 * did hash table lookup before we unhashed socket. They will achieve
1756 	 * receive queue and will be purged by socket destructor.
1757 	 *
1758 	 * Also we still have packets pending on receive queue and probably,
1759 	 * our own packets waiting in device queues. sock_destroy will drain
1760 	 * receive queue, but transmitted packets will delay socket destruction
1761 	 * until the last reference will be released.
1762 	 */
1763 
1764 	sock_orphan(sk);
1765 
1766 	xfrm_sk_free_policy(sk);
1767 
1768 	sk_refcnt_debug_release(sk);
1769 	sock_put(sk);
1770 }
1771 
1772 EXPORT_SYMBOL(sk_common_release);
1773 
1774 static DEFINE_RWLOCK(proto_list_lock);
1775 static LIST_HEAD(proto_list);
1776 
1777 int proto_register(struct proto *prot, int alloc_slab)
1778 {
1779 	char *request_sock_slab_name = NULL;
1780 	char *timewait_sock_slab_name;
1781 	int rc = -ENOBUFS;
1782 
1783 	if (alloc_slab) {
1784 		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
1785 					       SLAB_HWCACHE_ALIGN, NULL);
1786 
1787 		if (prot->slab == NULL) {
1788 			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
1789 			       prot->name);
1790 			goto out;
1791 		}
1792 
1793 		if (prot->rsk_prot != NULL) {
1794 			static const char mask[] = "request_sock_%s";
1795 
1796 			request_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
1797 			if (request_sock_slab_name == NULL)
1798 				goto out_free_sock_slab;
1799 
1800 			sprintf(request_sock_slab_name, mask, prot->name);
1801 			prot->rsk_prot->slab = kmem_cache_create(request_sock_slab_name,
1802 								 prot->rsk_prot->obj_size, 0,
1803 								 SLAB_HWCACHE_ALIGN, NULL);
1804 
1805 			if (prot->rsk_prot->slab == NULL) {
1806 				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
1807 				       prot->name);
1808 				goto out_free_request_sock_slab_name;
1809 			}
1810 		}
1811 
1812 		if (prot->twsk_prot != NULL) {
1813 			static const char mask[] = "tw_sock_%s";
1814 
1815 			timewait_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
1816 
1817 			if (timewait_sock_slab_name == NULL)
1818 				goto out_free_request_sock_slab;
1819 
1820 			sprintf(timewait_sock_slab_name, mask, prot->name);
1821 			prot->twsk_prot->twsk_slab =
1822 				kmem_cache_create(timewait_sock_slab_name,
1823 						  prot->twsk_prot->twsk_obj_size,
1824 						  0, SLAB_HWCACHE_ALIGN,
1825 						  NULL);
1826 			if (prot->twsk_prot->twsk_slab == NULL)
1827 				goto out_free_timewait_sock_slab_name;
1828 		}
1829 	}
1830 
1831 	write_lock(&proto_list_lock);
1832 	list_add(&prot->node, &proto_list);
1833 	write_unlock(&proto_list_lock);
1834 	rc = 0;
1835 out:
1836 	return rc;
1837 out_free_timewait_sock_slab_name:
1838 	kfree(timewait_sock_slab_name);
1839 out_free_request_sock_slab:
1840 	if (prot->rsk_prot && prot->rsk_prot->slab) {
1841 		kmem_cache_destroy(prot->rsk_prot->slab);
1842 		prot->rsk_prot->slab = NULL;
1843 	}
1844 out_free_request_sock_slab_name:
1845 	kfree(request_sock_slab_name);
1846 out_free_sock_slab:
1847 	kmem_cache_destroy(prot->slab);
1848 	prot->slab = NULL;
1849 	goto out;
1850 }
1851 
1852 EXPORT_SYMBOL(proto_register);
1853 
1854 void proto_unregister(struct proto *prot)
1855 {
1856 	write_lock(&proto_list_lock);
1857 	list_del(&prot->node);
1858 	write_unlock(&proto_list_lock);
1859 
1860 	if (prot->slab != NULL) {
1861 		kmem_cache_destroy(prot->slab);
1862 		prot->slab = NULL;
1863 	}
1864 
1865 	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
1866 		const char *name = kmem_cache_name(prot->rsk_prot->slab);
1867 
1868 		kmem_cache_destroy(prot->rsk_prot->slab);
1869 		kfree(name);
1870 		prot->rsk_prot->slab = NULL;
1871 	}
1872 
1873 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
1874 		const char *name = kmem_cache_name(prot->twsk_prot->twsk_slab);
1875 
1876 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
1877 		kfree(name);
1878 		prot->twsk_prot->twsk_slab = NULL;
1879 	}
1880 }
1881 
1882 EXPORT_SYMBOL(proto_unregister);
1883 
1884 #ifdef CONFIG_PROC_FS
1885 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
1886 {
1887 	read_lock(&proto_list_lock);
1888 	return seq_list_start_head(&proto_list, *pos);
1889 }
1890 
1891 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1892 {
1893 	return seq_list_next(v, &proto_list, pos);
1894 }
1895 
1896 static void proto_seq_stop(struct seq_file *seq, void *v)
1897 {
1898 	read_unlock(&proto_list_lock);
1899 }
1900 
1901 static char proto_method_implemented(const void *method)
1902 {
1903 	return method == NULL ? 'n' : 'y';
1904 }
1905 
1906 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
1907 {
1908 	seq_printf(seq, "%-9s %4u %6d  %6d   %-3s %6u   %-3s  %-10s "
1909 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
1910 		   proto->name,
1911 		   proto->obj_size,
1912 		   proto->sockets_allocated != NULL ? atomic_read(proto->sockets_allocated) : -1,
1913 		   proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
1914 		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
1915 		   proto->max_header,
1916 		   proto->slab == NULL ? "no" : "yes",
1917 		   module_name(proto->owner),
1918 		   proto_method_implemented(proto->close),
1919 		   proto_method_implemented(proto->connect),
1920 		   proto_method_implemented(proto->disconnect),
1921 		   proto_method_implemented(proto->accept),
1922 		   proto_method_implemented(proto->ioctl),
1923 		   proto_method_implemented(proto->init),
1924 		   proto_method_implemented(proto->destroy),
1925 		   proto_method_implemented(proto->shutdown),
1926 		   proto_method_implemented(proto->setsockopt),
1927 		   proto_method_implemented(proto->getsockopt),
1928 		   proto_method_implemented(proto->sendmsg),
1929 		   proto_method_implemented(proto->recvmsg),
1930 		   proto_method_implemented(proto->sendpage),
1931 		   proto_method_implemented(proto->bind),
1932 		   proto_method_implemented(proto->backlog_rcv),
1933 		   proto_method_implemented(proto->hash),
1934 		   proto_method_implemented(proto->unhash),
1935 		   proto_method_implemented(proto->get_port),
1936 		   proto_method_implemented(proto->enter_memory_pressure));
1937 }
1938 
1939 static int proto_seq_show(struct seq_file *seq, void *v)
1940 {
1941 	if (v == &proto_list)
1942 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
1943 			   "protocol",
1944 			   "size",
1945 			   "sockets",
1946 			   "memory",
1947 			   "press",
1948 			   "maxhdr",
1949 			   "slab",
1950 			   "module",
1951 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
1952 	else
1953 		proto_seq_printf(seq, list_entry(v, struct proto, node));
1954 	return 0;
1955 }
1956 
1957 static const struct seq_operations proto_seq_ops = {
1958 	.start  = proto_seq_start,
1959 	.next   = proto_seq_next,
1960 	.stop   = proto_seq_stop,
1961 	.show   = proto_seq_show,
1962 };
1963 
1964 static int proto_seq_open(struct inode *inode, struct file *file)
1965 {
1966 	return seq_open(file, &proto_seq_ops);
1967 }
1968 
1969 static const struct file_operations proto_seq_fops = {
1970 	.owner		= THIS_MODULE,
1971 	.open		= proto_seq_open,
1972 	.read		= seq_read,
1973 	.llseek		= seq_lseek,
1974 	.release	= seq_release,
1975 };
1976 
1977 static int __init proto_init(void)
1978 {
1979 	/* register /proc/net/protocols */
1980 	return proc_net_fops_create(&init_net, "protocols", S_IRUGO, &proto_seq_fops) == NULL ? -ENOBUFS : 0;
1981 }
1982 
1983 subsys_initcall(proto_init);
1984 
1985 #endif /* PROC_FS */
1986 
1987 EXPORT_SYMBOL(sk_alloc);
1988 EXPORT_SYMBOL(sk_free);
1989 EXPORT_SYMBOL(sk_send_sigurg);
1990 EXPORT_SYMBOL(sock_alloc_send_skb);
1991 EXPORT_SYMBOL(sock_init_data);
1992 EXPORT_SYMBOL(sock_kfree_s);
1993 EXPORT_SYMBOL(sock_kmalloc);
1994 EXPORT_SYMBOL(sock_no_accept);
1995 EXPORT_SYMBOL(sock_no_bind);
1996 EXPORT_SYMBOL(sock_no_connect);
1997 EXPORT_SYMBOL(sock_no_getname);
1998 EXPORT_SYMBOL(sock_no_getsockopt);
1999 EXPORT_SYMBOL(sock_no_ioctl);
2000 EXPORT_SYMBOL(sock_no_listen);
2001 EXPORT_SYMBOL(sock_no_mmap);
2002 EXPORT_SYMBOL(sock_no_poll);
2003 EXPORT_SYMBOL(sock_no_recvmsg);
2004 EXPORT_SYMBOL(sock_no_sendmsg);
2005 EXPORT_SYMBOL(sock_no_sendpage);
2006 EXPORT_SYMBOL(sock_no_setsockopt);
2007 EXPORT_SYMBOL(sock_no_shutdown);
2008 EXPORT_SYMBOL(sock_no_socketpair);
2009 EXPORT_SYMBOL(sock_rfree);
2010 EXPORT_SYMBOL(sock_setsockopt);
2011 EXPORT_SYMBOL(sock_wfree);
2012 EXPORT_SYMBOL(sock_wmalloc);
2013 EXPORT_SYMBOL(sock_i_uid);
2014 EXPORT_SYMBOL(sock_i_ino);
2015 EXPORT_SYMBOL(sysctl_optmem_max);
2016 #ifdef CONFIG_SYSCTL
2017 EXPORT_SYMBOL(sysctl_rmem_max);
2018 EXPORT_SYMBOL(sysctl_wmem_max);
2019 #endif
2020