sock.c revision 3ab5aee7fe840b5b1b35a8d1ac11c3de5281e611
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 * Authors:	Ross Biro
11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 *		Florian La Roche, <flla@stud.uni-sb.de>
13 *		Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 *		Alan Cox	: 	Numerous verify_area() problems
17 *		Alan Cox	:	Connecting on a connecting socket
18 *					now returns an error for tcp.
19 *		Alan Cox	:	sock->protocol is set correctly.
20 *					and is not sometimes left as 0.
21 *		Alan Cox	:	connect handles icmp errors on a
22 *					connect properly. Unfortunately there
23 *					is a restart syscall nasty there. I
24 *					can't match BSD without hacking the C
25 *					library. Ideas urgently sought!
26 *		Alan Cox	:	Disallow bind() to addresses that are
27 *					not ours - especially broadcast ones!!
28 *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29 *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30 *					instead they leave that for the DESTROY timer.
31 *		Alan Cox	:	Clean up error flag in accept
32 *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33 *					was buggy. Put a remove_sock() in the handler
34 *					for memory when we hit 0. Also altered the timer
35 *					code. The ACK stuff can wait and needs major
36 *					TCP layer surgery.
37 *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38 *					and fixed timer/inet_bh race.
39 *		Alan Cox	:	Added zapped flag for TCP
40 *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41 *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43 *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46 *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47 *	Pauline Middelink	:	identd support
48 *		Alan Cox	:	Fixed connect() taking signals I think.
49 *		Alan Cox	:	SO_LINGER supported
50 *		Alan Cox	:	Error reporting fixes
51 *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52 *		Alan Cox	:	inet sockets don't set sk->type!
53 *		Alan Cox	:	Split socket option code
54 *		Alan Cox	:	Callbacks
55 *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56 *		Alex		:	Removed restriction on inet fioctl
57 *		Alan Cox	:	Splitting INET from NET core
58 *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59 *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60 *		Alan Cox	:	Split IP from generic code
61 *		Alan Cox	:	New kfree_skbmem()
62 *		Alan Cox	:	Make SO_DEBUG superuser only.
63 *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64 *					(compatibility fix)
65 *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66 *		Alan Cox	:	Allocator for a socket is settable.
67 *		Alan Cox	:	SO_ERROR includes soft errors.
68 *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69 *		Alan Cox	: 	Generic socket allocation to make hooks
70 *					easier (suggested by Craig Metz).
71 *		Michael Pall	:	SO_ERROR returns positive errno again
72 *              Steve Whitehouse:       Added default destructor to free
73 *                                      protocol private data.
74 *              Steve Whitehouse:       Added various other default routines
75 *                                      common to several socket families.
76 *              Chris Evans     :       Call suser() check last on F_SETOWN
77 *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79 *		Andi Kleen	:	Fix write_space callback
80 *		Chris Evans	:	Security fixes - signedness again
81 *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 *		This program is free software; you can redistribute it and/or
87 *		modify it under the terms of the GNU General Public License
88 *		as published by the Free Software Foundation; either version
89 *		2 of the License, or (at your option) any later version.
90 */
91
92#include <linux/capability.h>
93#include <linux/errno.h>
94#include <linux/types.h>
95#include <linux/socket.h>
96#include <linux/in.h>
97#include <linux/kernel.h>
98#include <linux/module.h>
99#include <linux/proc_fs.h>
100#include <linux/seq_file.h>
101#include <linux/sched.h>
102#include <linux/timer.h>
103#include <linux/string.h>
104#include <linux/sockios.h>
105#include <linux/net.h>
106#include <linux/mm.h>
107#include <linux/slab.h>
108#include <linux/interrupt.h>
109#include <linux/poll.h>
110#include <linux/tcp.h>
111#include <linux/init.h>
112#include <linux/highmem.h>
113
114#include <asm/uaccess.h>
115#include <asm/system.h>
116
117#include <linux/netdevice.h>
118#include <net/protocol.h>
119#include <linux/skbuff.h>
120#include <net/net_namespace.h>
121#include <net/request_sock.h>
122#include <net/sock.h>
123#include <net/xfrm.h>
124#include <linux/ipsec.h>
125
126#include <linux/filter.h>
127
128#ifdef CONFIG_INET
129#include <net/tcp.h>
130#endif
131
132/*
133 * Each address family might have different locking rules, so we have
134 * one slock key per address family:
135 */
136static struct lock_class_key af_family_keys[AF_MAX];
137static struct lock_class_key af_family_slock_keys[AF_MAX];
138
139#ifdef CONFIG_DEBUG_LOCK_ALLOC
140/*
141 * Make lock validator output more readable. (we pre-construct these
142 * strings build-time, so that runtime initialization of socket
143 * locks is fast):
144 */
145static const char *af_family_key_strings[AF_MAX+1] = {
146  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
147  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
148  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
149  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
150  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
151  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
152  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
153  "sk_lock-21"       , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
154  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
155  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
156  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
157  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
158  "sk_lock-AF_MAX"
159};
160static const char *af_family_slock_key_strings[AF_MAX+1] = {
161  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
162  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
163  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
164  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
165  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
166  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
167  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
168  "slock-21"       , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
169  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
170  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
171  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
172  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
173  "slock-AF_MAX"
174};
175static 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-AF_CAN"      ,
186  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
187  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
188  "clock-AF_MAX"
189};
190#endif
191
192/*
193 * sk_callback_lock locking rules are per-address-family,
194 * so split the lock classes by using a per-AF key:
195 */
196static struct lock_class_key af_callback_keys[AF_MAX];
197
198/* Take into consideration the size of the struct sk_buff overhead in the
199 * determination of these values, since that is non-constant across
200 * platforms.  This makes socket queueing behavior and performance
201 * not depend upon such differences.
202 */
203#define _SK_MEM_PACKETS		256
204#define _SK_MEM_OVERHEAD	(sizeof(struct sk_buff) + 256)
205#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
206#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
207
208/* Run time adjustable parameters. */
209__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
210__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
211__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
212__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
213
214/* Maximal space eaten by iovec or ancilliary data plus some space */
215int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
216
217static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
218{
219	struct timeval tv;
220
221	if (optlen < sizeof(tv))
222		return -EINVAL;
223	if (copy_from_user(&tv, optval, sizeof(tv)))
224		return -EFAULT;
225	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
226		return -EDOM;
227
228	if (tv.tv_sec < 0) {
229		static int warned __read_mostly;
230
231		*timeo_p = 0;
232		if (warned < 10 && net_ratelimit()) {
233			warned++;
234			printk(KERN_INFO "sock_set_timeout: `%s' (pid %d) "
235			       "tries to set negative timeout\n",
236				current->comm, task_pid_nr(current));
237		}
238		return 0;
239	}
240	*timeo_p = MAX_SCHEDULE_TIMEOUT;
241	if (tv.tv_sec == 0 && tv.tv_usec == 0)
242		return 0;
243	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
244		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
245	return 0;
246}
247
248static void sock_warn_obsolete_bsdism(const char *name)
249{
250	static int warned;
251	static char warncomm[TASK_COMM_LEN];
252	if (strcmp(warncomm, current->comm) && warned < 5) {
253		strcpy(warncomm,  current->comm);
254		printk(KERN_WARNING "process `%s' is using obsolete "
255		       "%s SO_BSDCOMPAT\n", warncomm, name);
256		warned++;
257	}
258}
259
260static void sock_disable_timestamp(struct sock *sk)
261{
262	if (sock_flag(sk, SOCK_TIMESTAMP)) {
263		sock_reset_flag(sk, SOCK_TIMESTAMP);
264		net_disable_timestamp();
265	}
266}
267
268
269int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
270{
271	int err = 0;
272	int skb_len;
273
274	/* Cast sk->rcvbuf to unsigned... It's pointless, but reduces
275	   number of warnings when compiling with -W --ANK
276	 */
277	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
278	    (unsigned)sk->sk_rcvbuf) {
279		err = -ENOMEM;
280		goto out;
281	}
282
283	err = sk_filter(sk, skb);
284	if (err)
285		goto out;
286
287	if (!sk_rmem_schedule(sk, skb->truesize)) {
288		err = -ENOBUFS;
289		goto out;
290	}
291
292	skb->dev = NULL;
293	skb_set_owner_r(skb, sk);
294
295	/* Cache the SKB length before we tack it onto the receive
296	 * queue.  Once it is added it no longer belongs to us and
297	 * may be freed by other threads of control pulling packets
298	 * from the queue.
299	 */
300	skb_len = skb->len;
301
302	skb_queue_tail(&sk->sk_receive_queue, skb);
303
304	if (!sock_flag(sk, SOCK_DEAD))
305		sk->sk_data_ready(sk, skb_len);
306out:
307	return err;
308}
309EXPORT_SYMBOL(sock_queue_rcv_skb);
310
311int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
312{
313	int rc = NET_RX_SUCCESS;
314
315	if (sk_filter(sk, skb))
316		goto discard_and_relse;
317
318	skb->dev = NULL;
319
320	if (nested)
321		bh_lock_sock_nested(sk);
322	else
323		bh_lock_sock(sk);
324	if (!sock_owned_by_user(sk)) {
325		/*
326		 * trylock + unlock semantics:
327		 */
328		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
329
330		rc = sk_backlog_rcv(sk, skb);
331
332		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
333	} else
334		sk_add_backlog(sk, skb);
335	bh_unlock_sock(sk);
336out:
337	sock_put(sk);
338	return rc;
339discard_and_relse:
340	kfree_skb(skb);
341	goto out;
342}
343EXPORT_SYMBOL(sk_receive_skb);
344
345struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
346{
347	struct dst_entry *dst = sk->sk_dst_cache;
348
349	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
350		sk->sk_dst_cache = NULL;
351		dst_release(dst);
352		return NULL;
353	}
354
355	return dst;
356}
357EXPORT_SYMBOL(__sk_dst_check);
358
359struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
360{
361	struct dst_entry *dst = sk_dst_get(sk);
362
363	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
364		sk_dst_reset(sk);
365		dst_release(dst);
366		return NULL;
367	}
368
369	return dst;
370}
371EXPORT_SYMBOL(sk_dst_check);
372
373static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
374{
375	int ret = -ENOPROTOOPT;
376#ifdef CONFIG_NETDEVICES
377	struct net *net = sock_net(sk);
378	char devname[IFNAMSIZ];
379	int index;
380
381	/* Sorry... */
382	ret = -EPERM;
383	if (!capable(CAP_NET_RAW))
384		goto out;
385
386	ret = -EINVAL;
387	if (optlen < 0)
388		goto out;
389
390	/* Bind this socket to a particular device like "eth0",
391	 * as specified in the passed interface name. If the
392	 * name is "" or the option length is zero the socket
393	 * is not bound.
394	 */
395	if (optlen > IFNAMSIZ - 1)
396		optlen = IFNAMSIZ - 1;
397	memset(devname, 0, sizeof(devname));
398
399	ret = -EFAULT;
400	if (copy_from_user(devname, optval, optlen))
401		goto out;
402
403	if (devname[0] == '\0') {
404		index = 0;
405	} else {
406		struct net_device *dev = dev_get_by_name(net, devname);
407
408		ret = -ENODEV;
409		if (!dev)
410			goto out;
411
412		index = dev->ifindex;
413		dev_put(dev);
414	}
415
416	lock_sock(sk);
417	sk->sk_bound_dev_if = index;
418	sk_dst_reset(sk);
419	release_sock(sk);
420
421	ret = 0;
422
423out:
424#endif
425
426	return ret;
427}
428
429static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
430{
431	if (valbool)
432		sock_set_flag(sk, bit);
433	else
434		sock_reset_flag(sk, bit);
435}
436
437/*
438 *	This is meant for all protocols to use and covers goings on
439 *	at the socket level. Everything here is generic.
440 */
441
442int sock_setsockopt(struct socket *sock, int level, int optname,
443		    char __user *optval, int optlen)
444{
445	struct sock *sk=sock->sk;
446	int val;
447	int valbool;
448	struct linger ling;
449	int ret = 0;
450
451	/*
452	 *	Options without arguments
453	 */
454
455	if (optname == SO_BINDTODEVICE)
456		return sock_bindtodevice(sk, optval, optlen);
457
458	if (optlen < sizeof(int))
459		return -EINVAL;
460
461	if (get_user(val, (int __user *)optval))
462		return -EFAULT;
463
464	valbool = val?1:0;
465
466	lock_sock(sk);
467
468	switch(optname) {
469	case SO_DEBUG:
470		if (val && !capable(CAP_NET_ADMIN)) {
471			ret = -EACCES;
472		} else
473			sock_valbool_flag(sk, SOCK_DBG, valbool);
474		break;
475	case SO_REUSEADDR:
476		sk->sk_reuse = valbool;
477		break;
478	case SO_TYPE:
479	case SO_ERROR:
480		ret = -ENOPROTOOPT;
481		break;
482	case SO_DONTROUTE:
483		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
484		break;
485	case SO_BROADCAST:
486		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
487		break;
488	case SO_SNDBUF:
489		/* Don't error on this BSD doesn't and if you think
490		   about it this is right. Otherwise apps have to
491		   play 'guess the biggest size' games. RCVBUF/SNDBUF
492		   are treated in BSD as hints */
493
494		if (val > sysctl_wmem_max)
495			val = sysctl_wmem_max;
496set_sndbuf:
497		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
498		if ((val * 2) < SOCK_MIN_SNDBUF)
499			sk->sk_sndbuf = SOCK_MIN_SNDBUF;
500		else
501			sk->sk_sndbuf = val * 2;
502
503		/*
504		 *	Wake up sending tasks if we
505		 *	upped the value.
506		 */
507		sk->sk_write_space(sk);
508		break;
509
510	case SO_SNDBUFFORCE:
511		if (!capable(CAP_NET_ADMIN)) {
512			ret = -EPERM;
513			break;
514		}
515		goto set_sndbuf;
516
517	case SO_RCVBUF:
518		/* Don't error on this BSD doesn't and if you think
519		   about it this is right. Otherwise apps have to
520		   play 'guess the biggest size' games. RCVBUF/SNDBUF
521		   are treated in BSD as hints */
522
523		if (val > sysctl_rmem_max)
524			val = sysctl_rmem_max;
525set_rcvbuf:
526		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
527		/*
528		 * We double it on the way in to account for
529		 * "struct sk_buff" etc. overhead.   Applications
530		 * assume that the SO_RCVBUF setting they make will
531		 * allow that much actual data to be received on that
532		 * socket.
533		 *
534		 * Applications are unaware that "struct sk_buff" and
535		 * other overheads allocate from the receive buffer
536		 * during socket buffer allocation.
537		 *
538		 * And after considering the possible alternatives,
539		 * returning the value we actually used in getsockopt
540		 * is the most desirable behavior.
541		 */
542		if ((val * 2) < SOCK_MIN_RCVBUF)
543			sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
544		else
545			sk->sk_rcvbuf = val * 2;
546		break;
547
548	case SO_RCVBUFFORCE:
549		if (!capable(CAP_NET_ADMIN)) {
550			ret = -EPERM;
551			break;
552		}
553		goto set_rcvbuf;
554
555	case SO_KEEPALIVE:
556#ifdef CONFIG_INET
557		if (sk->sk_protocol == IPPROTO_TCP)
558			tcp_set_keepalive(sk, valbool);
559#endif
560		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
561		break;
562
563	case SO_OOBINLINE:
564		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
565		break;
566
567	case SO_NO_CHECK:
568		sk->sk_no_check = valbool;
569		break;
570
571	case SO_PRIORITY:
572		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
573			sk->sk_priority = val;
574		else
575			ret = -EPERM;
576		break;
577
578	case SO_LINGER:
579		if (optlen < sizeof(ling)) {
580			ret = -EINVAL;	/* 1003.1g */
581			break;
582		}
583		if (copy_from_user(&ling,optval,sizeof(ling))) {
584			ret = -EFAULT;
585			break;
586		}
587		if (!ling.l_onoff)
588			sock_reset_flag(sk, SOCK_LINGER);
589		else {
590#if (BITS_PER_LONG == 32)
591			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
592				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
593			else
594#endif
595				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
596			sock_set_flag(sk, SOCK_LINGER);
597		}
598		break;
599
600	case SO_BSDCOMPAT:
601		sock_warn_obsolete_bsdism("setsockopt");
602		break;
603
604	case SO_PASSCRED:
605		if (valbool)
606			set_bit(SOCK_PASSCRED, &sock->flags);
607		else
608			clear_bit(SOCK_PASSCRED, &sock->flags);
609		break;
610
611	case SO_TIMESTAMP:
612	case SO_TIMESTAMPNS:
613		if (valbool)  {
614			if (optname == SO_TIMESTAMP)
615				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
616			else
617				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
618			sock_set_flag(sk, SOCK_RCVTSTAMP);
619			sock_enable_timestamp(sk);
620		} else {
621			sock_reset_flag(sk, SOCK_RCVTSTAMP);
622			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
623		}
624		break;
625
626	case SO_RCVLOWAT:
627		if (val < 0)
628			val = INT_MAX;
629		sk->sk_rcvlowat = val ? : 1;
630		break;
631
632	case SO_RCVTIMEO:
633		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
634		break;
635
636	case SO_SNDTIMEO:
637		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
638		break;
639
640	case SO_ATTACH_FILTER:
641		ret = -EINVAL;
642		if (optlen == sizeof(struct sock_fprog)) {
643			struct sock_fprog fprog;
644
645			ret = -EFAULT;
646			if (copy_from_user(&fprog, optval, sizeof(fprog)))
647				break;
648
649			ret = sk_attach_filter(&fprog, sk);
650		}
651		break;
652
653	case SO_DETACH_FILTER:
654		ret = sk_detach_filter(sk);
655		break;
656
657	case SO_PASSSEC:
658		if (valbool)
659			set_bit(SOCK_PASSSEC, &sock->flags);
660		else
661			clear_bit(SOCK_PASSSEC, &sock->flags);
662		break;
663	case SO_MARK:
664		if (!capable(CAP_NET_ADMIN))
665			ret = -EPERM;
666		else {
667			sk->sk_mark = val;
668		}
669		break;
670
671		/* We implement the SO_SNDLOWAT etc to
672		   not be settable (1003.1g 5.3) */
673	default:
674		ret = -ENOPROTOOPT;
675		break;
676	}
677	release_sock(sk);
678	return ret;
679}
680
681
682int sock_getsockopt(struct socket *sock, int level, int optname,
683		    char __user *optval, int __user *optlen)
684{
685	struct sock *sk = sock->sk;
686
687	union {
688		int val;
689		struct linger ling;
690		struct timeval tm;
691	} v;
692
693	unsigned int lv = sizeof(int);
694	int len;
695
696	if (get_user(len, optlen))
697		return -EFAULT;
698	if (len < 0)
699		return -EINVAL;
700
701	switch(optname) {
702	case SO_DEBUG:
703		v.val = sock_flag(sk, SOCK_DBG);
704		break;
705
706	case SO_DONTROUTE:
707		v.val = sock_flag(sk, SOCK_LOCALROUTE);
708		break;
709
710	case SO_BROADCAST:
711		v.val = !!sock_flag(sk, SOCK_BROADCAST);
712		break;
713
714	case SO_SNDBUF:
715		v.val = sk->sk_sndbuf;
716		break;
717
718	case SO_RCVBUF:
719		v.val = sk->sk_rcvbuf;
720		break;
721
722	case SO_REUSEADDR:
723		v.val = sk->sk_reuse;
724		break;
725
726	case SO_KEEPALIVE:
727		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
728		break;
729
730	case SO_TYPE:
731		v.val = sk->sk_type;
732		break;
733
734	case SO_ERROR:
735		v.val = -sock_error(sk);
736		if (v.val==0)
737			v.val = xchg(&sk->sk_err_soft, 0);
738		break;
739
740	case SO_OOBINLINE:
741		v.val = !!sock_flag(sk, SOCK_URGINLINE);
742		break;
743
744	case SO_NO_CHECK:
745		v.val = sk->sk_no_check;
746		break;
747
748	case SO_PRIORITY:
749		v.val = sk->sk_priority;
750		break;
751
752	case SO_LINGER:
753		lv		= sizeof(v.ling);
754		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
755		v.ling.l_linger	= sk->sk_lingertime / HZ;
756		break;
757
758	case SO_BSDCOMPAT:
759		sock_warn_obsolete_bsdism("getsockopt");
760		break;
761
762	case SO_TIMESTAMP:
763		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
764				!sock_flag(sk, SOCK_RCVTSTAMPNS);
765		break;
766
767	case SO_TIMESTAMPNS:
768		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
769		break;
770
771	case SO_RCVTIMEO:
772		lv=sizeof(struct timeval);
773		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
774			v.tm.tv_sec = 0;
775			v.tm.tv_usec = 0;
776		} else {
777			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
778			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
779		}
780		break;
781
782	case SO_SNDTIMEO:
783		lv=sizeof(struct timeval);
784		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
785			v.tm.tv_sec = 0;
786			v.tm.tv_usec = 0;
787		} else {
788			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
789			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
790		}
791		break;
792
793	case SO_RCVLOWAT:
794		v.val = sk->sk_rcvlowat;
795		break;
796
797	case SO_SNDLOWAT:
798		v.val=1;
799		break;
800
801	case SO_PASSCRED:
802		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
803		break;
804
805	case SO_PEERCRED:
806		if (len > sizeof(sk->sk_peercred))
807			len = sizeof(sk->sk_peercred);
808		if (copy_to_user(optval, &sk->sk_peercred, len))
809			return -EFAULT;
810		goto lenout;
811
812	case SO_PEERNAME:
813	{
814		char address[128];
815
816		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
817			return -ENOTCONN;
818		if (lv < len)
819			return -EINVAL;
820		if (copy_to_user(optval, address, len))
821			return -EFAULT;
822		goto lenout;
823	}
824
825	/* Dubious BSD thing... Probably nobody even uses it, but
826	 * the UNIX standard wants it for whatever reason... -DaveM
827	 */
828	case SO_ACCEPTCONN:
829		v.val = sk->sk_state == TCP_LISTEN;
830		break;
831
832	case SO_PASSSEC:
833		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
834		break;
835
836	case SO_PEERSEC:
837		return security_socket_getpeersec_stream(sock, optval, optlen, len);
838
839	case SO_MARK:
840		v.val = sk->sk_mark;
841		break;
842
843	default:
844		return -ENOPROTOOPT;
845	}
846
847	if (len > lv)
848		len = lv;
849	if (copy_to_user(optval, &v, len))
850		return -EFAULT;
851lenout:
852	if (put_user(len, optlen))
853		return -EFAULT;
854	return 0;
855}
856
857/*
858 * Initialize an sk_lock.
859 *
860 * (We also register the sk_lock with the lock validator.)
861 */
862static inline void sock_lock_init(struct sock *sk)
863{
864	sock_lock_init_class_and_name(sk,
865			af_family_slock_key_strings[sk->sk_family],
866			af_family_slock_keys + sk->sk_family,
867			af_family_key_strings[sk->sk_family],
868			af_family_keys + sk->sk_family);
869}
870
871static void sock_copy(struct sock *nsk, const struct sock *osk)
872{
873#ifdef CONFIG_SECURITY_NETWORK
874	void *sptr = nsk->sk_security;
875#endif
876
877	memcpy(nsk, osk, osk->sk_prot->obj_size);
878#ifdef CONFIG_SECURITY_NETWORK
879	nsk->sk_security = sptr;
880	security_sk_clone(osk, nsk);
881#endif
882}
883
884static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
885		int family)
886{
887	struct sock *sk;
888	struct kmem_cache *slab;
889
890	slab = prot->slab;
891	if (slab != NULL)
892		sk = kmem_cache_alloc(slab, priority);
893	else
894		sk = kmalloc(prot->obj_size, priority);
895
896	if (sk != NULL) {
897		if (security_sk_alloc(sk, family, priority))
898			goto out_free;
899
900		if (!try_module_get(prot->owner))
901			goto out_free_sec;
902	}
903
904	return sk;
905
906out_free_sec:
907	security_sk_free(sk);
908out_free:
909	if (slab != NULL)
910		kmem_cache_free(slab, sk);
911	else
912		kfree(sk);
913	return NULL;
914}
915
916static void sk_prot_free(struct proto *prot, struct sock *sk)
917{
918	struct kmem_cache *slab;
919	struct module *owner;
920
921	owner = prot->owner;
922	slab = prot->slab;
923
924	security_sk_free(sk);
925	if (slab != NULL)
926		kmem_cache_free(slab, sk);
927	else
928		kfree(sk);
929	module_put(owner);
930}
931
932/**
933 *	sk_alloc - All socket objects are allocated here
934 *	@net: the applicable net namespace
935 *	@family: protocol family
936 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
937 *	@prot: struct proto associated with this new sock instance
938 */
939struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
940		      struct proto *prot)
941{
942	struct sock *sk;
943
944	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
945	if (sk) {
946		sk->sk_family = family;
947		/*
948		 * See comment in struct sock definition to understand
949		 * why we need sk_prot_creator -acme
950		 */
951		sk->sk_prot = sk->sk_prot_creator = prot;
952		sock_lock_init(sk);
953		sock_net_set(sk, get_net(net));
954	}
955
956	return sk;
957}
958
959void sk_free(struct sock *sk)
960{
961	struct sk_filter *filter;
962
963	if (sk->sk_destruct)
964		sk->sk_destruct(sk);
965
966	filter = rcu_dereference(sk->sk_filter);
967	if (filter) {
968		sk_filter_uncharge(sk, filter);
969		rcu_assign_pointer(sk->sk_filter, NULL);
970	}
971
972	sock_disable_timestamp(sk);
973
974	if (atomic_read(&sk->sk_omem_alloc))
975		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
976		       __func__, atomic_read(&sk->sk_omem_alloc));
977
978	put_net(sock_net(sk));
979	sk_prot_free(sk->sk_prot_creator, sk);
980}
981
982/*
983 * Last sock_put should drop referrence to sk->sk_net. It has already
984 * been dropped in sk_change_net. Taking referrence to stopping namespace
985 * is not an option.
986 * Take referrence to a socket to remove it from hash _alive_ and after that
987 * destroy it in the context of init_net.
988 */
989void sk_release_kernel(struct sock *sk)
990{
991	if (sk == NULL || sk->sk_socket == NULL)
992		return;
993
994	sock_hold(sk);
995	sock_release(sk->sk_socket);
996	release_net(sock_net(sk));
997	sock_net_set(sk, get_net(&init_net));
998	sock_put(sk);
999}
1000EXPORT_SYMBOL(sk_release_kernel);
1001
1002struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1003{
1004	struct sock *newsk;
1005
1006	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1007	if (newsk != NULL) {
1008		struct sk_filter *filter;
1009
1010		sock_copy(newsk, sk);
1011
1012		/* SANITY */
1013		get_net(sock_net(newsk));
1014		sk_node_init(&newsk->sk_node);
1015		sock_lock_init(newsk);
1016		bh_lock_sock(newsk);
1017		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1018
1019		atomic_set(&newsk->sk_rmem_alloc, 0);
1020		atomic_set(&newsk->sk_wmem_alloc, 0);
1021		atomic_set(&newsk->sk_omem_alloc, 0);
1022		skb_queue_head_init(&newsk->sk_receive_queue);
1023		skb_queue_head_init(&newsk->sk_write_queue);
1024#ifdef CONFIG_NET_DMA
1025		skb_queue_head_init(&newsk->sk_async_wait_queue);
1026#endif
1027
1028		rwlock_init(&newsk->sk_dst_lock);
1029		rwlock_init(&newsk->sk_callback_lock);
1030		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1031				af_callback_keys + newsk->sk_family,
1032				af_family_clock_key_strings[newsk->sk_family]);
1033
1034		newsk->sk_dst_cache	= NULL;
1035		newsk->sk_wmem_queued	= 0;
1036		newsk->sk_forward_alloc = 0;
1037		newsk->sk_send_head	= NULL;
1038		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1039
1040		sock_reset_flag(newsk, SOCK_DONE);
1041		skb_queue_head_init(&newsk->sk_error_queue);
1042
1043		filter = newsk->sk_filter;
1044		if (filter != NULL)
1045			sk_filter_charge(newsk, filter);
1046
1047		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1048			/* It is still raw copy of parent, so invalidate
1049			 * destructor and make plain sk_free() */
1050			newsk->sk_destruct = NULL;
1051			sk_free(newsk);
1052			newsk = NULL;
1053			goto out;
1054		}
1055
1056		newsk->sk_err	   = 0;
1057		newsk->sk_priority = 0;
1058		atomic_set(&newsk->sk_refcnt, 2);
1059
1060		/*
1061		 * Increment the counter in the same struct proto as the master
1062		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1063		 * is the same as sk->sk_prot->socks, as this field was copied
1064		 * with memcpy).
1065		 *
1066		 * This _changes_ the previous behaviour, where
1067		 * tcp_create_openreq_child always was incrementing the
1068		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1069		 * to be taken into account in all callers. -acme
1070		 */
1071		sk_refcnt_debug_inc(newsk);
1072		sk_set_socket(newsk, NULL);
1073		newsk->sk_sleep	 = NULL;
1074
1075		if (newsk->sk_prot->sockets_allocated)
1076			atomic_inc(newsk->sk_prot->sockets_allocated);
1077	}
1078out:
1079	return newsk;
1080}
1081
1082EXPORT_SYMBOL_GPL(sk_clone);
1083
1084void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1085{
1086	__sk_dst_set(sk, dst);
1087	sk->sk_route_caps = dst->dev->features;
1088	if (sk->sk_route_caps & NETIF_F_GSO)
1089		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1090	if (sk_can_gso(sk)) {
1091		if (dst->header_len) {
1092			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1093		} else {
1094			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1095			sk->sk_gso_max_size = dst->dev->gso_max_size;
1096		}
1097	}
1098}
1099EXPORT_SYMBOL_GPL(sk_setup_caps);
1100
1101void __init sk_init(void)
1102{
1103	if (num_physpages <= 4096) {
1104		sysctl_wmem_max = 32767;
1105		sysctl_rmem_max = 32767;
1106		sysctl_wmem_default = 32767;
1107		sysctl_rmem_default = 32767;
1108	} else if (num_physpages >= 131072) {
1109		sysctl_wmem_max = 131071;
1110		sysctl_rmem_max = 131071;
1111	}
1112}
1113
1114/*
1115 *	Simple resource managers for sockets.
1116 */
1117
1118
1119/*
1120 * Write buffer destructor automatically called from kfree_skb.
1121 */
1122void sock_wfree(struct sk_buff *skb)
1123{
1124	struct sock *sk = skb->sk;
1125
1126	/* In case it might be waiting for more memory. */
1127	atomic_sub(skb->truesize, &sk->sk_wmem_alloc);
1128	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE))
1129		sk->sk_write_space(sk);
1130	sock_put(sk);
1131}
1132
1133/*
1134 * Read buffer destructor automatically called from kfree_skb.
1135 */
1136void sock_rfree(struct sk_buff *skb)
1137{
1138	struct sock *sk = skb->sk;
1139
1140	skb_truesize_check(skb);
1141	atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
1142	sk_mem_uncharge(skb->sk, skb->truesize);
1143}
1144
1145
1146int sock_i_uid(struct sock *sk)
1147{
1148	int uid;
1149
1150	read_lock(&sk->sk_callback_lock);
1151	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1152	read_unlock(&sk->sk_callback_lock);
1153	return uid;
1154}
1155
1156unsigned long sock_i_ino(struct sock *sk)
1157{
1158	unsigned long ino;
1159
1160	read_lock(&sk->sk_callback_lock);
1161	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1162	read_unlock(&sk->sk_callback_lock);
1163	return ino;
1164}
1165
1166/*
1167 * Allocate a skb from the socket's send buffer.
1168 */
1169struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1170			     gfp_t priority)
1171{
1172	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1173		struct sk_buff * skb = alloc_skb(size, priority);
1174		if (skb) {
1175			skb_set_owner_w(skb, sk);
1176			return skb;
1177		}
1178	}
1179	return NULL;
1180}
1181
1182/*
1183 * Allocate a skb from the socket's receive buffer.
1184 */
1185struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1186			     gfp_t priority)
1187{
1188	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1189		struct sk_buff *skb = alloc_skb(size, priority);
1190		if (skb) {
1191			skb_set_owner_r(skb, sk);
1192			return skb;
1193		}
1194	}
1195	return NULL;
1196}
1197
1198/*
1199 * Allocate a memory block from the socket's option memory buffer.
1200 */
1201void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1202{
1203	if ((unsigned)size <= sysctl_optmem_max &&
1204	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1205		void *mem;
1206		/* First do the add, to avoid the race if kmalloc
1207		 * might sleep.
1208		 */
1209		atomic_add(size, &sk->sk_omem_alloc);
1210		mem = kmalloc(size, priority);
1211		if (mem)
1212			return mem;
1213		atomic_sub(size, &sk->sk_omem_alloc);
1214	}
1215	return NULL;
1216}
1217
1218/*
1219 * Free an option memory block.
1220 */
1221void sock_kfree_s(struct sock *sk, void *mem, int size)
1222{
1223	kfree(mem);
1224	atomic_sub(size, &sk->sk_omem_alloc);
1225}
1226
1227/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1228   I think, these locks should be removed for datagram sockets.
1229 */
1230static long sock_wait_for_wmem(struct sock * sk, long timeo)
1231{
1232	DEFINE_WAIT(wait);
1233
1234	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1235	for (;;) {
1236		if (!timeo)
1237			break;
1238		if (signal_pending(current))
1239			break;
1240		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1241		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
1242		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1243			break;
1244		if (sk->sk_shutdown & SEND_SHUTDOWN)
1245			break;
1246		if (sk->sk_err)
1247			break;
1248		timeo = schedule_timeout(timeo);
1249	}
1250	finish_wait(sk->sk_sleep, &wait);
1251	return timeo;
1252}
1253
1254
1255/*
1256 *	Generic send/receive buffer handlers
1257 */
1258
1259static struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1260					    unsigned long header_len,
1261					    unsigned long data_len,
1262					    int noblock, int *errcode)
1263{
1264	struct sk_buff *skb;
1265	gfp_t gfp_mask;
1266	long timeo;
1267	int err;
1268
1269	gfp_mask = sk->sk_allocation;
1270	if (gfp_mask & __GFP_WAIT)
1271		gfp_mask |= __GFP_REPEAT;
1272
1273	timeo = sock_sndtimeo(sk, noblock);
1274	while (1) {
1275		err = sock_error(sk);
1276		if (err != 0)
1277			goto failure;
1278
1279		err = -EPIPE;
1280		if (sk->sk_shutdown & SEND_SHUTDOWN)
1281			goto failure;
1282
1283		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1284			skb = alloc_skb(header_len, gfp_mask);
1285			if (skb) {
1286				int npages;
1287				int i;
1288
1289				/* No pages, we're done... */
1290				if (!data_len)
1291					break;
1292
1293				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1294				skb->truesize += data_len;
1295				skb_shinfo(skb)->nr_frags = npages;
1296				for (i = 0; i < npages; i++) {
1297					struct page *page;
1298					skb_frag_t *frag;
1299
1300					page = alloc_pages(sk->sk_allocation, 0);
1301					if (!page) {
1302						err = -ENOBUFS;
1303						skb_shinfo(skb)->nr_frags = i;
1304						kfree_skb(skb);
1305						goto failure;
1306					}
1307
1308					frag = &skb_shinfo(skb)->frags[i];
1309					frag->page = page;
1310					frag->page_offset = 0;
1311					frag->size = (data_len >= PAGE_SIZE ?
1312						      PAGE_SIZE :
1313						      data_len);
1314					data_len -= PAGE_SIZE;
1315				}
1316
1317				/* Full success... */
1318				break;
1319			}
1320			err = -ENOBUFS;
1321			goto failure;
1322		}
1323		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1324		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1325		err = -EAGAIN;
1326		if (!timeo)
1327			goto failure;
1328		if (signal_pending(current))
1329			goto interrupted;
1330		timeo = sock_wait_for_wmem(sk, timeo);
1331	}
1332
1333	skb_set_owner_w(skb, sk);
1334	return skb;
1335
1336interrupted:
1337	err = sock_intr_errno(timeo);
1338failure:
1339	*errcode = err;
1340	return NULL;
1341}
1342
1343struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1344				    int noblock, int *errcode)
1345{
1346	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1347}
1348
1349static void __lock_sock(struct sock *sk)
1350{
1351	DEFINE_WAIT(wait);
1352
1353	for (;;) {
1354		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1355					TASK_UNINTERRUPTIBLE);
1356		spin_unlock_bh(&sk->sk_lock.slock);
1357		schedule();
1358		spin_lock_bh(&sk->sk_lock.slock);
1359		if (!sock_owned_by_user(sk))
1360			break;
1361	}
1362	finish_wait(&sk->sk_lock.wq, &wait);
1363}
1364
1365static void __release_sock(struct sock *sk)
1366{
1367	struct sk_buff *skb = sk->sk_backlog.head;
1368
1369	do {
1370		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1371		bh_unlock_sock(sk);
1372
1373		do {
1374			struct sk_buff *next = skb->next;
1375
1376			skb->next = NULL;
1377			sk_backlog_rcv(sk, skb);
1378
1379			/*
1380			 * We are in process context here with softirqs
1381			 * disabled, use cond_resched_softirq() to preempt.
1382			 * This is safe to do because we've taken the backlog
1383			 * queue private:
1384			 */
1385			cond_resched_softirq();
1386
1387			skb = next;
1388		} while (skb != NULL);
1389
1390		bh_lock_sock(sk);
1391	} while ((skb = sk->sk_backlog.head) != NULL);
1392}
1393
1394/**
1395 * sk_wait_data - wait for data to arrive at sk_receive_queue
1396 * @sk:    sock to wait on
1397 * @timeo: for how long
1398 *
1399 * Now socket state including sk->sk_err is changed only under lock,
1400 * hence we may omit checks after joining wait queue.
1401 * We check receive queue before schedule() only as optimization;
1402 * it is very likely that release_sock() added new data.
1403 */
1404int sk_wait_data(struct sock *sk, long *timeo)
1405{
1406	int rc;
1407	DEFINE_WAIT(wait);
1408
1409	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
1410	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1411	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1412	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1413	finish_wait(sk->sk_sleep, &wait);
1414	return rc;
1415}
1416
1417EXPORT_SYMBOL(sk_wait_data);
1418
1419/**
1420 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1421 *	@sk: socket
1422 *	@size: memory size to allocate
1423 *	@kind: allocation type
1424 *
1425 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1426 *	rmem allocation. This function assumes that protocols which have
1427 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1428 */
1429int __sk_mem_schedule(struct sock *sk, int size, int kind)
1430{
1431	struct proto *prot = sk->sk_prot;
1432	int amt = sk_mem_pages(size);
1433	int allocated;
1434
1435	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1436	allocated = atomic_add_return(amt, prot->memory_allocated);
1437
1438	/* Under limit. */
1439	if (allocated <= prot->sysctl_mem[0]) {
1440		if (prot->memory_pressure && *prot->memory_pressure)
1441			*prot->memory_pressure = 0;
1442		return 1;
1443	}
1444
1445	/* Under pressure. */
1446	if (allocated > prot->sysctl_mem[1])
1447		if (prot->enter_memory_pressure)
1448			prot->enter_memory_pressure(sk);
1449
1450	/* Over hard limit. */
1451	if (allocated > prot->sysctl_mem[2])
1452		goto suppress_allocation;
1453
1454	/* guarantee minimum buffer size under pressure */
1455	if (kind == SK_MEM_RECV) {
1456		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1457			return 1;
1458	} else { /* SK_MEM_SEND */
1459		if (sk->sk_type == SOCK_STREAM) {
1460			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1461				return 1;
1462		} else if (atomic_read(&sk->sk_wmem_alloc) <
1463			   prot->sysctl_wmem[0])
1464				return 1;
1465	}
1466
1467	if (prot->memory_pressure) {
1468		if (!*prot->memory_pressure ||
1469		    prot->sysctl_mem[2] > atomic_read(prot->sockets_allocated) *
1470		    sk_mem_pages(sk->sk_wmem_queued +
1471				 atomic_read(&sk->sk_rmem_alloc) +
1472				 sk->sk_forward_alloc))
1473			return 1;
1474	}
1475
1476suppress_allocation:
1477
1478	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1479		sk_stream_moderate_sndbuf(sk);
1480
1481		/* Fail only if socket is _under_ its sndbuf.
1482		 * In this case we cannot block, so that we have to fail.
1483		 */
1484		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1485			return 1;
1486	}
1487
1488	/* Alas. Undo changes. */
1489	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1490	atomic_sub(amt, prot->memory_allocated);
1491	return 0;
1492}
1493
1494EXPORT_SYMBOL(__sk_mem_schedule);
1495
1496/**
1497 *	__sk_reclaim - reclaim memory_allocated
1498 *	@sk: socket
1499 */
1500void __sk_mem_reclaim(struct sock *sk)
1501{
1502	struct proto *prot = sk->sk_prot;
1503
1504	atomic_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1505		   prot->memory_allocated);
1506	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1507
1508	if (prot->memory_pressure && *prot->memory_pressure &&
1509	    (atomic_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1510		*prot->memory_pressure = 0;
1511}
1512
1513EXPORT_SYMBOL(__sk_mem_reclaim);
1514
1515
1516/*
1517 * Set of default routines for initialising struct proto_ops when
1518 * the protocol does not support a particular function. In certain
1519 * cases where it makes no sense for a protocol to have a "do nothing"
1520 * function, some default processing is provided.
1521 */
1522
1523int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1524{
1525	return -EOPNOTSUPP;
1526}
1527
1528int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1529		    int len, int flags)
1530{
1531	return -EOPNOTSUPP;
1532}
1533
1534int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1535{
1536	return -EOPNOTSUPP;
1537}
1538
1539int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1540{
1541	return -EOPNOTSUPP;
1542}
1543
1544int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1545		    int *len, int peer)
1546{
1547	return -EOPNOTSUPP;
1548}
1549
1550unsigned int sock_no_poll(struct file * file, struct socket *sock, poll_table *pt)
1551{
1552	return 0;
1553}
1554
1555int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1556{
1557	return -EOPNOTSUPP;
1558}
1559
1560int sock_no_listen(struct socket *sock, int backlog)
1561{
1562	return -EOPNOTSUPP;
1563}
1564
1565int sock_no_shutdown(struct socket *sock, int how)
1566{
1567	return -EOPNOTSUPP;
1568}
1569
1570int sock_no_setsockopt(struct socket *sock, int level, int optname,
1571		    char __user *optval, int optlen)
1572{
1573	return -EOPNOTSUPP;
1574}
1575
1576int sock_no_getsockopt(struct socket *sock, int level, int optname,
1577		    char __user *optval, int __user *optlen)
1578{
1579	return -EOPNOTSUPP;
1580}
1581
1582int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1583		    size_t len)
1584{
1585	return -EOPNOTSUPP;
1586}
1587
1588int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1589		    size_t len, int flags)
1590{
1591	return -EOPNOTSUPP;
1592}
1593
1594int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1595{
1596	/* Mirror missing mmap method error code */
1597	return -ENODEV;
1598}
1599
1600ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1601{
1602	ssize_t res;
1603	struct msghdr msg = {.msg_flags = flags};
1604	struct kvec iov;
1605	char *kaddr = kmap(page);
1606	iov.iov_base = kaddr + offset;
1607	iov.iov_len = size;
1608	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1609	kunmap(page);
1610	return res;
1611}
1612
1613/*
1614 *	Default Socket Callbacks
1615 */
1616
1617static void sock_def_wakeup(struct sock *sk)
1618{
1619	read_lock(&sk->sk_callback_lock);
1620	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1621		wake_up_interruptible_all(sk->sk_sleep);
1622	read_unlock(&sk->sk_callback_lock);
1623}
1624
1625static void sock_def_error_report(struct sock *sk)
1626{
1627	read_lock(&sk->sk_callback_lock);
1628	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1629		wake_up_interruptible(sk->sk_sleep);
1630	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1631	read_unlock(&sk->sk_callback_lock);
1632}
1633
1634static void sock_def_readable(struct sock *sk, int len)
1635{
1636	read_lock(&sk->sk_callback_lock);
1637	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1638		wake_up_interruptible_sync(sk->sk_sleep);
1639	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1640	read_unlock(&sk->sk_callback_lock);
1641}
1642
1643static void sock_def_write_space(struct sock *sk)
1644{
1645	read_lock(&sk->sk_callback_lock);
1646
1647	/* Do not wake up a writer until he can make "significant"
1648	 * progress.  --DaveM
1649	 */
1650	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1651		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1652			wake_up_interruptible_sync(sk->sk_sleep);
1653
1654		/* Should agree with poll, otherwise some programs break */
1655		if (sock_writeable(sk))
1656			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1657	}
1658
1659	read_unlock(&sk->sk_callback_lock);
1660}
1661
1662static void sock_def_destruct(struct sock *sk)
1663{
1664	kfree(sk->sk_protinfo);
1665}
1666
1667void sk_send_sigurg(struct sock *sk)
1668{
1669	if (sk->sk_socket && sk->sk_socket->file)
1670		if (send_sigurg(&sk->sk_socket->file->f_owner))
1671			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1672}
1673
1674void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1675		    unsigned long expires)
1676{
1677	if (!mod_timer(timer, expires))
1678		sock_hold(sk);
1679}
1680
1681EXPORT_SYMBOL(sk_reset_timer);
1682
1683void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1684{
1685	if (timer_pending(timer) && del_timer(timer))
1686		__sock_put(sk);
1687}
1688
1689EXPORT_SYMBOL(sk_stop_timer);
1690
1691void sock_init_data(struct socket *sock, struct sock *sk)
1692{
1693	skb_queue_head_init(&sk->sk_receive_queue);
1694	skb_queue_head_init(&sk->sk_write_queue);
1695	skb_queue_head_init(&sk->sk_error_queue);
1696#ifdef CONFIG_NET_DMA
1697	skb_queue_head_init(&sk->sk_async_wait_queue);
1698#endif
1699
1700	sk->sk_send_head	=	NULL;
1701
1702	init_timer(&sk->sk_timer);
1703
1704	sk->sk_allocation	=	GFP_KERNEL;
1705	sk->sk_rcvbuf		=	sysctl_rmem_default;
1706	sk->sk_sndbuf		=	sysctl_wmem_default;
1707	sk->sk_state		=	TCP_CLOSE;
1708	sk_set_socket(sk, sock);
1709
1710	sock_set_flag(sk, SOCK_ZAPPED);
1711
1712	if (sock) {
1713		sk->sk_type	=	sock->type;
1714		sk->sk_sleep	=	&sock->wait;
1715		sock->sk	=	sk;
1716	} else
1717		sk->sk_sleep	=	NULL;
1718
1719	rwlock_init(&sk->sk_dst_lock);
1720	rwlock_init(&sk->sk_callback_lock);
1721	lockdep_set_class_and_name(&sk->sk_callback_lock,
1722			af_callback_keys + sk->sk_family,
1723			af_family_clock_key_strings[sk->sk_family]);
1724
1725	sk->sk_state_change	=	sock_def_wakeup;
1726	sk->sk_data_ready	=	sock_def_readable;
1727	sk->sk_write_space	=	sock_def_write_space;
1728	sk->sk_error_report	=	sock_def_error_report;
1729	sk->sk_destruct		=	sock_def_destruct;
1730
1731	sk->sk_sndmsg_page	=	NULL;
1732	sk->sk_sndmsg_off	=	0;
1733
1734	sk->sk_peercred.pid 	=	0;
1735	sk->sk_peercred.uid	=	-1;
1736	sk->sk_peercred.gid	=	-1;
1737	sk->sk_write_pending	=	0;
1738	sk->sk_rcvlowat		=	1;
1739	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
1740	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
1741
1742	sk->sk_stamp = ktime_set(-1L, 0);
1743
1744	atomic_set(&sk->sk_refcnt, 1);
1745	atomic_set(&sk->sk_drops, 0);
1746}
1747
1748void lock_sock_nested(struct sock *sk, int subclass)
1749{
1750	might_sleep();
1751	spin_lock_bh(&sk->sk_lock.slock);
1752	if (sk->sk_lock.owned)
1753		__lock_sock(sk);
1754	sk->sk_lock.owned = 1;
1755	spin_unlock(&sk->sk_lock.slock);
1756	/*
1757	 * The sk_lock has mutex_lock() semantics here:
1758	 */
1759	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
1760	local_bh_enable();
1761}
1762
1763EXPORT_SYMBOL(lock_sock_nested);
1764
1765void release_sock(struct sock *sk)
1766{
1767	/*
1768	 * The sk_lock has mutex_unlock() semantics:
1769	 */
1770	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1771
1772	spin_lock_bh(&sk->sk_lock.slock);
1773	if (sk->sk_backlog.tail)
1774		__release_sock(sk);
1775	sk->sk_lock.owned = 0;
1776	if (waitqueue_active(&sk->sk_lock.wq))
1777		wake_up(&sk->sk_lock.wq);
1778	spin_unlock_bh(&sk->sk_lock.slock);
1779}
1780EXPORT_SYMBOL(release_sock);
1781
1782int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
1783{
1784	struct timeval tv;
1785	if (!sock_flag(sk, SOCK_TIMESTAMP))
1786		sock_enable_timestamp(sk);
1787	tv = ktime_to_timeval(sk->sk_stamp);
1788	if (tv.tv_sec == -1)
1789		return -ENOENT;
1790	if (tv.tv_sec == 0) {
1791		sk->sk_stamp = ktime_get_real();
1792		tv = ktime_to_timeval(sk->sk_stamp);
1793	}
1794	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
1795}
1796EXPORT_SYMBOL(sock_get_timestamp);
1797
1798int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
1799{
1800	struct timespec ts;
1801	if (!sock_flag(sk, SOCK_TIMESTAMP))
1802		sock_enable_timestamp(sk);
1803	ts = ktime_to_timespec(sk->sk_stamp);
1804	if (ts.tv_sec == -1)
1805		return -ENOENT;
1806	if (ts.tv_sec == 0) {
1807		sk->sk_stamp = ktime_get_real();
1808		ts = ktime_to_timespec(sk->sk_stamp);
1809	}
1810	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
1811}
1812EXPORT_SYMBOL(sock_get_timestampns);
1813
1814void sock_enable_timestamp(struct sock *sk)
1815{
1816	if (!sock_flag(sk, SOCK_TIMESTAMP)) {
1817		sock_set_flag(sk, SOCK_TIMESTAMP);
1818		net_enable_timestamp();
1819	}
1820}
1821
1822/*
1823 *	Get a socket option on an socket.
1824 *
1825 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
1826 *	asynchronous errors should be reported by getsockopt. We assume
1827 *	this means if you specify SO_ERROR (otherwise whats the point of it).
1828 */
1829int sock_common_getsockopt(struct socket *sock, int level, int optname,
1830			   char __user *optval, int __user *optlen)
1831{
1832	struct sock *sk = sock->sk;
1833
1834	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1835}
1836
1837EXPORT_SYMBOL(sock_common_getsockopt);
1838
1839#ifdef CONFIG_COMPAT
1840int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
1841				  char __user *optval, int __user *optlen)
1842{
1843	struct sock *sk = sock->sk;
1844
1845	if (sk->sk_prot->compat_getsockopt != NULL)
1846		return sk->sk_prot->compat_getsockopt(sk, level, optname,
1847						      optval, optlen);
1848	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1849}
1850EXPORT_SYMBOL(compat_sock_common_getsockopt);
1851#endif
1852
1853int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1854			struct msghdr *msg, size_t size, int flags)
1855{
1856	struct sock *sk = sock->sk;
1857	int addr_len = 0;
1858	int err;
1859
1860	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
1861				   flags & ~MSG_DONTWAIT, &addr_len);
1862	if (err >= 0)
1863		msg->msg_namelen = addr_len;
1864	return err;
1865}
1866
1867EXPORT_SYMBOL(sock_common_recvmsg);
1868
1869/*
1870 *	Set socket options on an inet socket.
1871 */
1872int sock_common_setsockopt(struct socket *sock, int level, int optname,
1873			   char __user *optval, int optlen)
1874{
1875	struct sock *sk = sock->sk;
1876
1877	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1878}
1879
1880EXPORT_SYMBOL(sock_common_setsockopt);
1881
1882#ifdef CONFIG_COMPAT
1883int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
1884				  char __user *optval, int optlen)
1885{
1886	struct sock *sk = sock->sk;
1887
1888	if (sk->sk_prot->compat_setsockopt != NULL)
1889		return sk->sk_prot->compat_setsockopt(sk, level, optname,
1890						      optval, optlen);
1891	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1892}
1893EXPORT_SYMBOL(compat_sock_common_setsockopt);
1894#endif
1895
1896void sk_common_release(struct sock *sk)
1897{
1898	if (sk->sk_prot->destroy)
1899		sk->sk_prot->destroy(sk);
1900
1901	/*
1902	 * Observation: when sock_common_release is called, processes have
1903	 * no access to socket. But net still has.
1904	 * Step one, detach it from networking:
1905	 *
1906	 * A. Remove from hash tables.
1907	 */
1908
1909	sk->sk_prot->unhash(sk);
1910
1911	/*
1912	 * In this point socket cannot receive new packets, but it is possible
1913	 * that some packets are in flight because some CPU runs receiver and
1914	 * did hash table lookup before we unhashed socket. They will achieve
1915	 * receive queue and will be purged by socket destructor.
1916	 *
1917	 * Also we still have packets pending on receive queue and probably,
1918	 * our own packets waiting in device queues. sock_destroy will drain
1919	 * receive queue, but transmitted packets will delay socket destruction
1920	 * until the last reference will be released.
1921	 */
1922
1923	sock_orphan(sk);
1924
1925	xfrm_sk_free_policy(sk);
1926
1927	sk_refcnt_debug_release(sk);
1928	sock_put(sk);
1929}
1930
1931EXPORT_SYMBOL(sk_common_release);
1932
1933static DEFINE_RWLOCK(proto_list_lock);
1934static LIST_HEAD(proto_list);
1935
1936#ifdef CONFIG_PROC_FS
1937#define PROTO_INUSE_NR	64	/* should be enough for the first time */
1938struct prot_inuse {
1939	int val[PROTO_INUSE_NR];
1940};
1941
1942static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
1943
1944#ifdef CONFIG_NET_NS
1945void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
1946{
1947	int cpu = smp_processor_id();
1948	per_cpu_ptr(net->core.inuse, cpu)->val[prot->inuse_idx] += val;
1949}
1950EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
1951
1952int sock_prot_inuse_get(struct net *net, struct proto *prot)
1953{
1954	int cpu, idx = prot->inuse_idx;
1955	int res = 0;
1956
1957	for_each_possible_cpu(cpu)
1958		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
1959
1960	return res >= 0 ? res : 0;
1961}
1962EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
1963
1964static int sock_inuse_init_net(struct net *net)
1965{
1966	net->core.inuse = alloc_percpu(struct prot_inuse);
1967	return net->core.inuse ? 0 : -ENOMEM;
1968}
1969
1970static void sock_inuse_exit_net(struct net *net)
1971{
1972	free_percpu(net->core.inuse);
1973}
1974
1975static struct pernet_operations net_inuse_ops = {
1976	.init = sock_inuse_init_net,
1977	.exit = sock_inuse_exit_net,
1978};
1979
1980static __init int net_inuse_init(void)
1981{
1982	if (register_pernet_subsys(&net_inuse_ops))
1983		panic("Cannot initialize net inuse counters");
1984
1985	return 0;
1986}
1987
1988core_initcall(net_inuse_init);
1989#else
1990static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
1991
1992void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
1993{
1994	__get_cpu_var(prot_inuse).val[prot->inuse_idx] += val;
1995}
1996EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
1997
1998int sock_prot_inuse_get(struct net *net, struct proto *prot)
1999{
2000	int cpu, idx = prot->inuse_idx;
2001	int res = 0;
2002
2003	for_each_possible_cpu(cpu)
2004		res += per_cpu(prot_inuse, cpu).val[idx];
2005
2006	return res >= 0 ? res : 0;
2007}
2008EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2009#endif
2010
2011static void assign_proto_idx(struct proto *prot)
2012{
2013	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2014
2015	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2016		printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2017		return;
2018	}
2019
2020	set_bit(prot->inuse_idx, proto_inuse_idx);
2021}
2022
2023static void release_proto_idx(struct proto *prot)
2024{
2025	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2026		clear_bit(prot->inuse_idx, proto_inuse_idx);
2027}
2028#else
2029static inline void assign_proto_idx(struct proto *prot)
2030{
2031}
2032
2033static inline void release_proto_idx(struct proto *prot)
2034{
2035}
2036#endif
2037
2038int proto_register(struct proto *prot, int alloc_slab)
2039{
2040	char *request_sock_slab_name = NULL;
2041	char *timewait_sock_slab_name;
2042
2043	if (alloc_slab) {
2044		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2045					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2046					NULL);
2047
2048		if (prot->slab == NULL) {
2049			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2050			       prot->name);
2051			goto out;
2052		}
2053
2054		if (prot->rsk_prot != NULL) {
2055			static const char mask[] = "request_sock_%s";
2056
2057			request_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
2058			if (request_sock_slab_name == NULL)
2059				goto out_free_sock_slab;
2060
2061			sprintf(request_sock_slab_name, mask, prot->name);
2062			prot->rsk_prot->slab = kmem_cache_create(request_sock_slab_name,
2063								 prot->rsk_prot->obj_size, 0,
2064								 SLAB_HWCACHE_ALIGN, NULL);
2065
2066			if (prot->rsk_prot->slab == NULL) {
2067				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2068				       prot->name);
2069				goto out_free_request_sock_slab_name;
2070			}
2071		}
2072
2073		if (prot->twsk_prot != NULL) {
2074			static const char mask[] = "tw_sock_%s";
2075
2076			timewait_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
2077
2078			if (timewait_sock_slab_name == NULL)
2079				goto out_free_request_sock_slab;
2080
2081			sprintf(timewait_sock_slab_name, mask, prot->name);
2082			prot->twsk_prot->twsk_slab =
2083				kmem_cache_create(timewait_sock_slab_name,
2084						  prot->twsk_prot->twsk_obj_size,
2085						  0,
2086						  SLAB_HWCACHE_ALIGN |
2087							prot->slab_flags,
2088						  NULL);
2089			if (prot->twsk_prot->twsk_slab == NULL)
2090				goto out_free_timewait_sock_slab_name;
2091		}
2092	}
2093
2094	write_lock(&proto_list_lock);
2095	list_add(&prot->node, &proto_list);
2096	assign_proto_idx(prot);
2097	write_unlock(&proto_list_lock);
2098	return 0;
2099
2100out_free_timewait_sock_slab_name:
2101	kfree(timewait_sock_slab_name);
2102out_free_request_sock_slab:
2103	if (prot->rsk_prot && prot->rsk_prot->slab) {
2104		kmem_cache_destroy(prot->rsk_prot->slab);
2105		prot->rsk_prot->slab = NULL;
2106	}
2107out_free_request_sock_slab_name:
2108	kfree(request_sock_slab_name);
2109out_free_sock_slab:
2110	kmem_cache_destroy(prot->slab);
2111	prot->slab = NULL;
2112out:
2113	return -ENOBUFS;
2114}
2115
2116EXPORT_SYMBOL(proto_register);
2117
2118void proto_unregister(struct proto *prot)
2119{
2120	write_lock(&proto_list_lock);
2121	release_proto_idx(prot);
2122	list_del(&prot->node);
2123	write_unlock(&proto_list_lock);
2124
2125	if (prot->slab != NULL) {
2126		kmem_cache_destroy(prot->slab);
2127		prot->slab = NULL;
2128	}
2129
2130	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2131		const char *name = kmem_cache_name(prot->rsk_prot->slab);
2132
2133		kmem_cache_destroy(prot->rsk_prot->slab);
2134		kfree(name);
2135		prot->rsk_prot->slab = NULL;
2136	}
2137
2138	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2139		const char *name = kmem_cache_name(prot->twsk_prot->twsk_slab);
2140
2141		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2142		kfree(name);
2143		prot->twsk_prot->twsk_slab = NULL;
2144	}
2145}
2146
2147EXPORT_SYMBOL(proto_unregister);
2148
2149#ifdef CONFIG_PROC_FS
2150static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2151	__acquires(proto_list_lock)
2152{
2153	read_lock(&proto_list_lock);
2154	return seq_list_start_head(&proto_list, *pos);
2155}
2156
2157static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2158{
2159	return seq_list_next(v, &proto_list, pos);
2160}
2161
2162static void proto_seq_stop(struct seq_file *seq, void *v)
2163	__releases(proto_list_lock)
2164{
2165	read_unlock(&proto_list_lock);
2166}
2167
2168static char proto_method_implemented(const void *method)
2169{
2170	return method == NULL ? 'n' : 'y';
2171}
2172
2173static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2174{
2175	seq_printf(seq, "%-9s %4u %6d  %6d   %-3s %6u   %-3s  %-10s "
2176			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2177		   proto->name,
2178		   proto->obj_size,
2179		   proto->sockets_allocated != NULL ? atomic_read(proto->sockets_allocated) : -1,
2180		   proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
2181		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2182		   proto->max_header,
2183		   proto->slab == NULL ? "no" : "yes",
2184		   module_name(proto->owner),
2185		   proto_method_implemented(proto->close),
2186		   proto_method_implemented(proto->connect),
2187		   proto_method_implemented(proto->disconnect),
2188		   proto_method_implemented(proto->accept),
2189		   proto_method_implemented(proto->ioctl),
2190		   proto_method_implemented(proto->init),
2191		   proto_method_implemented(proto->destroy),
2192		   proto_method_implemented(proto->shutdown),
2193		   proto_method_implemented(proto->setsockopt),
2194		   proto_method_implemented(proto->getsockopt),
2195		   proto_method_implemented(proto->sendmsg),
2196		   proto_method_implemented(proto->recvmsg),
2197		   proto_method_implemented(proto->sendpage),
2198		   proto_method_implemented(proto->bind),
2199		   proto_method_implemented(proto->backlog_rcv),
2200		   proto_method_implemented(proto->hash),
2201		   proto_method_implemented(proto->unhash),
2202		   proto_method_implemented(proto->get_port),
2203		   proto_method_implemented(proto->enter_memory_pressure));
2204}
2205
2206static int proto_seq_show(struct seq_file *seq, void *v)
2207{
2208	if (v == &proto_list)
2209		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2210			   "protocol",
2211			   "size",
2212			   "sockets",
2213			   "memory",
2214			   "press",
2215			   "maxhdr",
2216			   "slab",
2217			   "module",
2218			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2219	else
2220		proto_seq_printf(seq, list_entry(v, struct proto, node));
2221	return 0;
2222}
2223
2224static const struct seq_operations proto_seq_ops = {
2225	.start  = proto_seq_start,
2226	.next   = proto_seq_next,
2227	.stop   = proto_seq_stop,
2228	.show   = proto_seq_show,
2229};
2230
2231static int proto_seq_open(struct inode *inode, struct file *file)
2232{
2233	return seq_open(file, &proto_seq_ops);
2234}
2235
2236static const struct file_operations proto_seq_fops = {
2237	.owner		= THIS_MODULE,
2238	.open		= proto_seq_open,
2239	.read		= seq_read,
2240	.llseek		= seq_lseek,
2241	.release	= seq_release,
2242};
2243
2244static int __init proto_init(void)
2245{
2246	/* register /proc/net/protocols */
2247	return proc_net_fops_create(&init_net, "protocols", S_IRUGO, &proto_seq_fops) == NULL ? -ENOBUFS : 0;
2248}
2249
2250subsys_initcall(proto_init);
2251
2252#endif /* PROC_FS */
2253
2254EXPORT_SYMBOL(sk_alloc);
2255EXPORT_SYMBOL(sk_free);
2256EXPORT_SYMBOL(sk_send_sigurg);
2257EXPORT_SYMBOL(sock_alloc_send_skb);
2258EXPORT_SYMBOL(sock_init_data);
2259EXPORT_SYMBOL(sock_kfree_s);
2260EXPORT_SYMBOL(sock_kmalloc);
2261EXPORT_SYMBOL(sock_no_accept);
2262EXPORT_SYMBOL(sock_no_bind);
2263EXPORT_SYMBOL(sock_no_connect);
2264EXPORT_SYMBOL(sock_no_getname);
2265EXPORT_SYMBOL(sock_no_getsockopt);
2266EXPORT_SYMBOL(sock_no_ioctl);
2267EXPORT_SYMBOL(sock_no_listen);
2268EXPORT_SYMBOL(sock_no_mmap);
2269EXPORT_SYMBOL(sock_no_poll);
2270EXPORT_SYMBOL(sock_no_recvmsg);
2271EXPORT_SYMBOL(sock_no_sendmsg);
2272EXPORT_SYMBOL(sock_no_sendpage);
2273EXPORT_SYMBOL(sock_no_setsockopt);
2274EXPORT_SYMBOL(sock_no_shutdown);
2275EXPORT_SYMBOL(sock_no_socketpair);
2276EXPORT_SYMBOL(sock_rfree);
2277EXPORT_SYMBOL(sock_setsockopt);
2278EXPORT_SYMBOL(sock_wfree);
2279EXPORT_SYMBOL(sock_wmalloc);
2280EXPORT_SYMBOL(sock_i_uid);
2281EXPORT_SYMBOL(sock_i_ino);
2282EXPORT_SYMBOL(sysctl_optmem_max);
2283