aboutsummaryrefslogtreecommitdiffstats
path: root/net/socket.c
blob: 5f76ab8a15944fa5dd2374f75078d6eb52f00530 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
/*
 * NET		An implementation of the SOCKET network access protocol.
 *
 * Version:	@(#)socket.c	1.1.93	18/02/95
 *
 * Authors:	Orest Zborowski, <obz@Kodak.COM>
 *		Ross Biro
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *
 * Fixes:
 *		Anonymous	:	NOTSOCK/BADF cleanup. Error fix in
 *					shutdown()
 *		Alan Cox	:	verify_area() fixes
 *		Alan Cox	:	Removed DDI
 *		Jonathan Kamens	:	SOCK_DGRAM reconnect bug
 *		Alan Cox	:	Moved a load of checks to the very
 *					top level.
 *		Alan Cox	:	Move address structures to/from user
 *					mode above the protocol layers.
 *		Rob Janssen	:	Allow 0 length sends.
 *		Alan Cox	:	Asynchronous I/O support (cribbed from the
 *					tty drivers).
 *		Niibe Yutaka	:	Asynchronous I/O for writes (4.4BSD style)
 *		Jeff Uphoff	:	Made max number of sockets command-line
 *					configurable.
 *		Matti Aarnio	:	Made the number of sockets dynamic,
 *					to be allocated when needed, and mr.
 *					Uphoff's max is used as max to be
 *					allowed to allocate.
 *		Linus		:	Argh. removed all the socket allocation
 *					altogether: it's in the inode now.
 *		Alan Cox	:	Made sock_alloc()/sock_release() public
 *					for NetROM and future kernel nfsd type
 *					stuff.
 *		Alan Cox	:	sendmsg/recvmsg basics.
 *		Tom Dyas	:	Export net symbols.
 *		Marcin Dalecki	:	Fixed problems with CONFIG_NET="n".
 *		Alan Cox	:	Added thread locking to sys_* calls
 *					for sockets. May have errors at the
 *					moment.
 *		Kevin Buhr	:	Fixed the dumb errors in the above.
 *		Andi Kleen	:	Some small cleanups, optimizations,
 *					and fixed a copy_from_user() bug.
 *		Tigran Aivazian	:	sys_send(args) calls sys_sendto(args, NULL, 0)
 *		Tigran Aivazian	:	Made listen(2) backlog sanity checks 
 *					protocol-independent
 *
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *
 *	This module is effectively the top level interface to the BSD socket
 *	paradigm. 
 *
 *	Based upon Swansea University Computer Society NET3.039
 */

#include <linux/config.h>
#include <linux/mm.h>
#include <linux/smp_lock.h>
#include <linux/socket.h>
#include <linux/file.h>
#include <linux/net.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/wanrouter.h>
#include <linux/if_bridge.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/cache.h>
#include <linux/module.h>
#include <linux/highmem.h>
#include <linux/divert.h>
#include <linux/mount.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <linux/kmod.h>
#include <linux/audit.h>

#ifdef CONFIG_NET_RADIO
#include <linux/wireless.h>		/* Note : will define WIRELESS_EXT */
#endif	/* CONFIG_NET_RADIO */

#include <asm/uaccess.h>
#include <asm/unistd.h>

#include <net/compat.h>

#include <net/sock.h>
#include <linux/netfilter.h>

static int sock_no_open(struct inode *irrelevant, struct file *dontcare);
static ssize_t sock_aio_read(struct kiocb *iocb, char __user *buf,
			 size_t size, loff_t pos);
static ssize_t sock_aio_write(struct kiocb *iocb, const char __user *buf,
			  size_t size, loff_t pos);
static int sock_mmap(struct file *file, struct vm_area_struct * vma);

static int sock_close(struct inode *inode, struct file *file);
static unsigned int sock_poll(struct file *file,
			      struct poll_table_struct *wait);
static long sock_ioctl(struct file *file,
		      unsigned int cmd, unsigned long arg);
static int sock_fasync(int fd, struct file *filp, int on);
static ssize_t sock_readv(struct file *file, const struct iovec *vector,
			  unsigned long count, loff_t *ppos);
static ssize_t sock_writev(struct file *file, const struct iovec *vector,
			  unsigned long count, loff_t *ppos);
static ssize_t sock_sendpage(struct file *file, struct page *page,
			     int offset, size_t size, loff_t *ppos, int more);


/*
 *	Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
 *	in the operation structures but are done directly via the socketcall() multiplexor.
 */

static struct file_operations socket_file_ops = {
	.owner =	THIS_MODULE,
	.llseek =	no_llseek,
	.aio_read =	sock_aio_read,
	.aio_write =	sock_aio_write,
	.poll =		sock_poll,
	.unlocked_ioctl = sock_ioctl,
	.mmap =		sock_mmap,
	.open =		sock_no_open,	/* special open code to disallow open via /proc */
	.release =	sock_close,
	.fasync =	sock_fasync,
	.readv =	sock_readv,
	.writev =	sock_writev,
	.sendpage =	sock_sendpage
};

/*
 *	The protocol list. Each protocol is registered in here.
 */

static struct net_proto_family *net_families[NPROTO];

#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
static atomic_t net_family_lockct = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(net_family_lock);

/* The strategy is: modifications net_family vector are short, do not
   sleep and veeery rare, but read access should be free of any exclusive
   locks.
 */

static void net_family_write_lock(void)
{
	spin_lock(&net_family_lock);
	while (atomic_read(&net_family_lockct) != 0) {
		spin_unlock(&net_family_lock);

		yield();

		spin_lock(&net_family_lock);
	}
}

static __inline__ void net_family_write_unlock(void)
{
	spin_unlock(&net_family_lock);
}

static __inline__ void net_family_read_lock(void)
{
	atomic_inc(&net_family_lockct);
	spin_unlock_wait(&net_family_lock);
}

static __inline__ void net_family_read_unlock(void)
{
	atomic_dec(&net_family_lockct);
}

#else
#define net_family_write_lock() do { } while(0)
#define net_family_write_unlock() do { } while(0)
#define net_family_read_lock() do { } while(0)
#define net_family_read_unlock() do { } while(0)
#endif


/*
 *	Statistics counters of the socket lists
 */

static DEFINE_PER_CPU(int, sockets_in_use) = 0;

/*
 *	Support routines. Move socket addresses back and forth across the kernel/user
 *	divide and look after the messy bits.
 */

#define MAX_SOCK_ADDR	128		/* 108 for Unix domain - 
					   16 for IP, 16 for IPX,
					   24 for IPv6,
					   about 80 for AX.25 
					   must be at least one bigger than
					   the AF_UNIX size (see net/unix/af_unix.c
					   :unix_mkname()).  
					 */
					 
/**
 *	move_addr_to_kernel	-	copy a socket address into kernel space
 *	@uaddr: Address in user space
 *	@kaddr: Address in kernel space
 *	@ulen: Length in user space
 *
 *	The address is copied into kernel space. If the provided address is
 *	too long an error code of -EINVAL is returned. If the copy gives
 *	invalid addresses -EFAULT is returned. On a success 0 is returned.
 */

int move_addr_to_kernel(void __user *uaddr, int ulen, void *kaddr)
{
	if(ulen<0||ulen>MAX_SOCK_ADDR)
		return -EINVAL;
	if(ulen==0)
		return 0;
	if(copy_from_user(kaddr,uaddr,ulen))
		return -EFAULT;
	return audit_sockaddr(ulen, kaddr);
}

/**
 *	move_addr_to_user	-	copy an address to user space
 *	@kaddr: kernel space address
 *	@klen: length of address in kernel
 *	@uaddr: user space address
 *	@ulen: pointer to user length field
 *
 *	The value pointed to by ulen on entry is the buffer length available.
 *	This is overwritten with the buffer space used. -EINVAL is returned
 *	if an overlong buffer is specified or a negative buffer size. -EFAULT
 *	is returned if either the buffer or the length field are not
 *	accessible.
 *	After copying the data up to the limit the user specifies, the true
 *	length of the data is written over the length limit the user
 *	specified. Zero is returned for a success.
 */
 
int move_addr_to_user(void *kaddr, int klen, void __user *uaddr, int __user *ulen)
{
	int err;
	int len;

	if((err=get_user(len, ulen)))
		return err;
	if(len>klen)
		len=klen;
	if(len<0 || len> MAX_SOCK_ADDR)
		return -EINVAL;
	if(len)
	{
		if(copy_to_user(uaddr,kaddr,len))
			return -EFAULT;
	}
	/*
	 *	"fromlen shall refer to the value before truncation.."
	 *			1003.1g
	 */
	return __put_user(klen, ulen);
}

#define SOCKFS_MAGIC 0x534F434B

static kmem_cache_t * sock_inode_cachep;

static struct inode *sock_alloc_inode(struct super_block *sb)
{
	struct socket_alloc *ei;
	ei = (struct socket_alloc *)kmem_cache_alloc(sock_inode_cachep, SLAB_KERNEL);
	if (!ei)
		return NULL;
	init_waitqueue_head(&ei->socket.wait);
	
	ei->socket.fasync_list = NULL;
	ei->socket.state = SS_UNCONNECTED;
	ei->socket.flags = 0;
	ei->socket.ops = NULL;
	ei->socket.sk = NULL;
	ei->socket.file = NULL;
	ei->socket.flags = 0;

	return &ei->vfs_inode;
}

static void sock_destroy_inode(struct inode *inode)
{
	kmem_cache_free(sock_inode_cachep,
			container_of(inode, struct socket_alloc, vfs_inode));
}

static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
{
	struct socket_alloc *ei = (struct socket_alloc *) foo;

	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
	    SLAB_CTOR_CONSTRUCTOR)
		inode_init_once(&ei->vfs_inode);
}
 
static int init_inodecache(void)
{
	sock_inode_cachep = kmem_cache_create("sock_inode_cache",
				sizeof(struct socket_alloc),
				0, SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT,
				init_once, NULL);
	if (sock_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static struct super_operations sockfs_ops = {
	.alloc_inode =	sock_alloc_inode,
	.destroy_inode =sock_destroy_inode,
	.statfs =	simple_statfs,
};

static struct super_block *sockfs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return get_sb_pseudo(fs_type, "socket:", &sockfs_ops, SOCKFS_MAGIC);
}

static struct vfsmount *sock_mnt;

static struct file_system_type sock_fs_type = {
	.name =		"sockfs",
	.get_sb =	sockfs_get_sb,
	.kill_sb =	kill_anon_super,
};
static int sockfs_delete_dentry(struct dentry *dentry)
{
	return 1;
}
static struct dentry_operations sockfs_dentry_operations = {
	.d_delete =	sockfs_delete_dentry,
};

/*
 *	Obtains the first available file descriptor and sets it up for use.
 *
 *	This function creates file structure and maps it to fd space
 *	of current process. On success it returns file descriptor
 *	and file struct implicitly stored in sock->file.
 *	Note that another thread may close file descriptor before we return
 *	from this function. We use the fact that now we do not refer
 *	to socket after mapping. If one day we will need it, this
 *	function will increment ref. count on file by 1.
 *
 *	In any case returned fd MAY BE not valid!
 *	This race condition is unavoidable
 *	with shared fd spaces, we cannot solve it inside kernel,
 *	but we take care of internal coherence yet.
 */

int sock_map_fd(struct socket *sock)
{
	int fd;
	struct qstr this;
	char name[32];

	/*
	 *	Find a file descriptor suitable for return to the user. 
	 */

	fd = get_unused_fd();
	if (fd >= 0) {
		struct file *file = get_empty_filp();

		if (!file) {
			put_unused_fd(fd);
			fd = -ENFILE;
			goto out;
		}

		this.len = sprintf(name, "[%lu]", SOCK_INODE(sock)->i_ino);
		this.name = name;
		this.hash = SOCK_INODE(sock)->i_ino;

		file->f_dentry = d_alloc(sock_mnt->mnt_sb->s_root, &this);
		if (!file->f_dentry) {
			put_filp(file);
			put_unused_fd(fd);
			fd = -ENOMEM;
			goto out;
		}
		file->f_dentry->d_op = &sockfs_dentry_operations;
		d_add(file->f_dentry, SOCK_INODE(sock));
		file->f_vfsmnt = mntget(sock_mnt);
		file->f_mapping = file->f_dentry->d_inode->i_mapping;

		sock->file = file;
		file->f_op = SOCK_INODE(sock)->i_fop = &socket_file_ops;
		file->f_mode = FMODE_READ | FMODE_WRITE;
		file->f_flags = O_RDWR;
		file->f_pos = 0;
		file->private_data = sock;
		fd_install(fd, file);
	}

out:
	return fd;
}

/**
 *	sockfd_lookup	- 	Go from a file number to its socket slot
 *	@fd: file handle
 *	@err: pointer to an error code return
 *
 *	The file handle passed in is locked and the socket it is bound
 *	too is returned. If an error occurs the err pointer is overwritten
 *	with a negative errno code and NULL is returned. The function checks
 *	for both invalid handles and passing a handle which is not a socket.
 *
 *	On a success the socket object pointer is returned.
 */

struct socket *sockfd_lookup(int fd, int *err)
{
	struct file *file;
	struct inode *inode;
	struct socket *sock;

	if (!(file = fget(fd)))
	{
		*err = -EBADF;
		return NULL;
	}

	if (file->f_op == &socket_file_ops)
		return file->private_data;	/* set in sock_map_fd */

	inode = file->f_dentry->d_inode;
	if (!S_ISSOCK(inode->i_mode)) {
		*err = -ENOTSOCK;
		fput(file);
		return NULL;
	}

	sock = SOCKET_I(inode);
	if (sock->file != file) {
		printk(KERN_ERR "socki_lookup: socket file changed!\n");
		sock->file = file;
	}
	return sock;
}

/**
 *	sock_alloc	-	allocate a socket
 *	
 *	Allocate a new inode and socket object. The two are bound together
 *	and initialised. The socket is then returned. If we are out of inodes
 *	NULL is returned.
 */

static struct socket *sock_alloc(void)
{
	struct inode * inode;
	struct socket * sock;

	inode = new_inode(sock_mnt->mnt_sb);
	if (!inode)
		return NULL;

	sock = SOCKET_I(inode);

	inode->i_mode = S_IFSOCK|S_IRWXUGO;
	inode->i_uid = current->fsuid;
	inode->i_gid = current->fsgid;

	get_cpu_var(sockets_in_use)++;
	put_cpu_var(sockets_in_use);
	return sock;
}

/*
 *	In theory you can't get an open on this inode, but /proc provides
 *	a back door. Remember to keep it shut otherwise you'll let the
 *	creepy crawlies in.
 */
  
static int sock_no_open(struct inode *irrelevant, struct file *dontcare)
{
	return -ENXIO;
}

struct file_operations bad_sock_fops = {
	.owner = THIS_MODULE,
	.open = sock_no_open,
};

/**
 *	sock_release	-	close a socket
 *	@sock: socket to close
 *
 *	The socket is released from the protocol stack if it has a release
 *	callback, and the inode is then released if the socket is bound to
 *	an inode not a file. 
 */
 
void sock_release(struct socket *sock)
{
	if (sock->ops) {
		struct module *owner = sock->ops->owner;

		sock->ops->release(sock);
		sock->ops = NULL;
		module_put(owner);
	}

	if (sock->fasync_list)
		printk(KERN_ERR "sock_release: fasync list not empty!\n");

	get_cpu_var(sockets_in_use)--;
	put_cpu_var(sockets_in_use);
	if (!sock->file) {
		iput(SOCK_INODE(sock));
		return;
	}
	sock->file=NULL;
}

static inline int __sock_sendmsg(struct kiocb *iocb, struct socket *sock, 
				 struct msghdr *msg, size_t size)
{
	struct sock_iocb *si = kiocb_to_siocb(iocb);
	int err;

	si->sock = sock;
	si->scm = NULL;
	si->msg = msg;
	si->size = size;

	err = security_socket_sendmsg(sock, msg, size);
	if (err)
		return err;

	return sock->ops->sendmsg(iocb, sock, msg, size);
}

int sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
	struct kiocb iocb;
	struct sock_iocb siocb;
	int ret;

	init_sync_kiocb(&iocb, NULL);
	iocb.private = &siocb;
	ret = __sock_sendmsg(&iocb, sock, msg, size);
	if (-EIOCBQUEUED == ret)
		ret = wait_on_sync_kiocb(&iocb);
	return ret;
}

int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
		   struct kvec *vec, size_t num, size_t size)
{
	mm_segment_t oldfs = get_fs();
	int result;

	set_fs(KERNEL_DS);
	/*
	 * the following is safe, since for compiler definitions of kvec and
	 * iovec are identical, yielding the same in-core layout and alignment
	 */
	msg->msg_iov = (struct iovec *)vec,
	msg->msg_iovlen = num;
	result = sock_sendmsg(sock, msg, size);
	set_fs(oldfs);
	return result;
}

static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock, 
				 struct msghdr *msg, size_t size, int flags)
{
	int err;
	struct sock_iocb *si = kiocb_to_siocb(iocb);

	si->sock = sock;
	si->scm = NULL;
	si->msg = msg;
	si->size = size;
	si->flags = flags;

	err = security_socket_recvmsg(sock, msg, size, flags);
	if (err)
		return err;

	return sock->ops->recvmsg(iocb, sock, msg, size, flags);
}

int sock_recvmsg(struct socket *sock, struct msghdr *msg, 
		 size_t size, int flags)
{
	struct kiocb iocb;
	struct sock_iocb siocb;
	int ret;

        init_sync_kiocb(&iocb, NULL);
	iocb.private = &siocb;
	ret = __sock_recvmsg(&iocb, sock, msg, size, flags);
	if (-EIOCBQUEUED == ret)
		ret = wait_on_sync_kiocb(&iocb);
	return ret;
}

int kernel_recvmsg(struct socket *sock, struct msghdr *msg, 
		   struct kvec *vec, size_t num,
		   size_t size, int flags)
{
	mm_segment_t oldfs = get_fs();
	int result;

	set_fs(KERNEL_DS);
	/*
	 * the following is safe, since for compiler definitions of kvec and
	 * iovec are identical, yielding the same in-core layout and alignment
	 */
	msg->msg_iov = (struct iovec *)vec,
	msg->msg_iovlen = num;
	result = sock_recvmsg(sock, msg, size, flags);
	set_fs(oldfs);
	return result;
}

static void sock_aio_dtor(struct kiocb *iocb)
{
	kfree(iocb->private);
}

/*
 *	Read data from a socket. ubuf is a user mode pointer. We make sure the user
 *	area ubuf...ubuf+size-1 is writable before asking the protocol.
 */

static ssize_t sock_aio_read(struct kiocb *iocb, char __user *ubuf,
			 size_t size, loff_t pos)
{
	struct sock_iocb *x, siocb;
	struct socket *sock;
	int flags;

	if (pos != 0)
		return -ESPIPE;
	if (size==0)		/* Match SYS5 behaviour */
		return 0;

	if (is_sync_kiocb(iocb))
		x = &siocb;
	else {
		x = kmalloc(sizeof(struct sock_iocb), GFP_KERNEL);
		if (!x)
			return -ENOMEM;
		iocb->ki_dtor = sock_aio_dtor;
	}
	iocb->private = x;
	x->kiocb = iocb;
	sock = SOCKET_I(iocb->ki_filp->f_dentry->d_inode); 

	x->async_msg.msg_name = NULL;
	x->async_msg.msg_namelen = 0;
	x->async_msg.msg_iov = &x->async_iov;
	x->async_msg.msg_iovlen = 1;
	x->async_msg.msg_control = NULL;
	x->async_msg.msg_controllen = 0;
	x->async_iov.iov_base = ubuf;
	x->async_iov.iov_len = size;
	flags = !(iocb->ki_filp->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;

	return __sock_recvmsg(iocb, sock, &x->async_msg, size, flags);
}


/*
 *	Write data to a socket. We verify that the user area ubuf..ubuf+size-1
 *	is readable by the user process.
 */

static ssize_t sock_aio_write(struct kiocb *iocb, const char __user *ubuf,
			  size_t size, loff_t pos)
{
	struct sock_iocb *x, siocb;
	struct socket *sock;
	
	if (pos != 0)
		return -ESPIPE;
	if(size==0)		/* Match SYS5 behaviour */
		return 0;

	if (is_sync_kiocb(iocb))
		x = &siocb;
	else {
		x = kmalloc(sizeof(struct sock_iocb), GFP_KERNEL);
		if (!x)
			return -ENOMEM;
		iocb->ki_dtor = sock_aio_dtor;
	}
	iocb->private = x;
	x->kiocb = iocb;
	sock = SOCKET_I(iocb->ki_filp->f_dentry->d_inode); 

	x->async_msg.msg_name = NULL;
	x->async_msg.msg_namelen = 0;
	x->async_msg.msg_iov = &x->async_iov;
	x->async_msg.msg_iovlen = 1;
	x->async_msg.msg_control = NULL;
	x->async_msg.msg_controllen = 0;
	x->async_msg.msg_flags = !(iocb->ki_filp->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
	if (sock->type == SOCK_SEQPACKET)
		x->async_msg.msg_flags |= MSG_EOR;
	x->async_iov.iov_base = (void __user *)ubuf;
	x->async_iov.iov_len = size;
	
	return __sock_sendmsg(iocb, sock, &x->async_msg, size);
}

ssize_t sock_sendpage(struct file *file, struct page *page,
		      int offset, size_t size, loff_t *ppos, int more)
{
	struct socket *sock;
	int flags;

	sock = SOCKET_I(file->f_dentry->d_inode);

	flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
	if (more)
		flags |= MSG_MORE;

	return sock->ops->sendpage(sock, page, offset, size, flags);
}

static int sock_readv_writev(int type, struct inode * inode,
			     struct file * file, const struct iovec * iov,
			     long count, size_t size)
{
	struct msghdr msg;
	struct socket *sock;

	sock = SOCKET_I(inode);

	msg.msg_name = NULL;
	msg.msg_namelen = 0;
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_iov = (struct iovec *) iov;
	msg.msg_iovlen = count;
	msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;

	/* read() does a VERIFY_WRITE */
	if (type == VERIFY_WRITE)
		return sock_recvmsg(sock, &msg, size, msg.msg_flags);

	if (sock->type == SOCK_SEQPACKET)
		msg.msg_flags |= MSG_EOR;

	return sock_sendmsg(sock, &msg, size);
}

static ssize_t sock_readv(struct file *file, const struct iovec *vector,
			  unsigned long count, loff_t *ppos)
{
	size_t tot_len = 0;
	int i;
        for (i = 0 ; i < count ; i++)
                tot_len += vector[i].iov_len;
	return sock_readv_writev(VERIFY_WRITE, file->f_dentry->d_inode,
				 file, vector, count, tot_len);
}
	
static ssize_t sock_writev(struct file *file, const struct iovec *vector,
			   unsigned long count, loff_t *ppos)
{
	size_t tot_len = 0;
	int i;
        for (i = 0 ; i < count ; i++)
                tot_len += vector[i].iov_len;
	return sock_readv_writev(VERIFY_READ, file->f_dentry->d_inode,
				 file, vector, count, tot_len);
}


/*
 * Atomic setting of ioctl hooks to avoid race
 * with module unload.
 */

static DECLARE_MUTEX(br_ioctl_mutex);
static int (*br_ioctl_hook)(unsigned int cmd, void __user *arg) = NULL;

void brioctl_set(int (*hook)(unsigned int, void __user *))
{
	down(&br_ioctl_mutex);
	br_ioctl_hook = hook;
	up(&br_ioctl_mutex);
}
EXPORT_SYMBOL(brioctl_set);

static DECLARE_MUTEX(vlan_ioctl_mutex);
static int (*vlan_ioctl_hook)(void __user *arg);

void vlan_ioctl_set(int (*hook)(void __user *))
{
	down(&vlan_ioctl_mutex);
	vlan_ioctl_hook = hook;
	up(&vlan_ioctl_mutex);
}
EXPORT_SYMBOL(vlan_ioctl_set);

static DECLARE_MUTEX(dlci_ioctl_mutex);
static int (*dlci_ioctl_hook)(unsigned int, void __user *);

void dlci_ioctl_set(int (*hook)(unsigned int, void __user *))
{
	down(&dlci_ioctl_mutex);
	dlci_ioctl_hook = hook;
	up(&dlci_ioctl_mutex);
}
EXPORT_SYMBOL(dlci_ioctl_set);

/*
 *	With an ioctl, arg may well be a user mode pointer, but we don't know
 *	what to do with it - that's up to the protocol still.
 */

static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
	struct socket *sock;
	void __user *argp = (void __user *)arg;
	int pid, err;

	sock = SOCKET_I(file->f_dentry->d_inode);
	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15)) {
		err = dev_ioctl(cmd, argp);
	} else
#ifdef WIRELESS_EXT
	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
		err = dev_ioctl(cmd, argp);
	} else
#endif	/* WIRELESS_EXT */
	switch (cmd) {
		case FIOSETOWN:
		case SIOCSPGRP:
			err = -EFAULT;
			if (get_user(pid, (int __user *)argp))
				break;
			err = f_setown(sock->file, pid, 1);
			break;
		case FIOGETOWN:
		case SIOCGPGRP:
			err = put_user(sock->file->f_owner.pid, (int __user *)argp);
			break;
		case SIOCGIFBR:
		case SIOCSIFBR:
		case SIOCBRADDBR:
		case SIOCBRDELBR:
			err = -ENOPKG;
			if (!br_ioctl_hook)
				request_module("bridge");

			down(&br_ioctl_mutex);
			if (br_ioctl_hook) 
				err = br_ioctl_hook(cmd, argp);
			up(&br_ioctl_mutex);
			break;
		case SIOCGIFVLAN:
		case SIOCSIFVLAN:
			err = -ENOPKG;
			if (!vlan_ioctl_hook)
				request_module("8021q");

			down(&vlan_ioctl_mutex);
			if (vlan_ioctl_hook)
				err = vlan_ioctl_hook(argp);
			up(&vlan_ioctl_mutex);
			break;
		case SIOCGIFDIVERT:
		case SIOCSIFDIVERT:
		/* Convert this to call through a hook */
			err = divert_ioctl(cmd, argp);
			break;
		case SIOCADDDLCI:
		case SIOCDELDLCI:
			err = -ENOPKG;
			if (!dlci_ioctl_hook)
				request_module("dlci");

			if (dlci_ioctl_hook) {
				down(&dlci_ioctl_mutex);
				err = dlci_ioctl_hook(cmd, argp);
				up(&dlci_ioctl_mutex);
			}
			break;
		default:
			err = sock->ops->ioctl(sock, cmd, arg);
			break;
	}
	return err;
}

int sock_create_lite(int family, int type, int protocol, struct socket **res)
{
	int err;
	struct socket *sock = NULL;
	
	err = security_socket_create(family, type, protocol, 1);
	if (err)
		goto out;

	sock = sock_alloc();
	if (!sock) {
		err = -ENOMEM;
		goto out;
	}

	security_socket_post_create(sock, family, type, protocol, 1);
	sock->type = type;
out:
	*res = sock;
	return err;
}

/* No kernel lock held - perfect */
static unsigned int sock_poll(struct file *file, poll_table * wait)
{
	struct socket *sock;

	/*
	 *	We can't return errors to poll, so it's either yes or no. 
	 */
	sock = SOCKET_I(file->f_dentry->d_inode);
	return sock->ops->poll(file, sock, wait);
}

static int sock_mmap(struct file * file, struct vm_area_struct * vma)
{
	struct socket *sock = SOCKET_I(file->f_dentry->d_inode);

	return sock->ops->mmap(file, sock, vma);
}

int sock_close(struct inode *inode, struct file *filp)
{
	/*
	 *	It was possible the inode is NULL we were 
	 *	closing an unfinished socket. 
	 */

	if (!inode)
	{
		printk(KERN_DEBUG "sock_close: NULL inode\n");
		return 0;
	}
	sock_fasync(-1, filp, 0);
	sock_release(SOCKET_I(inode));
	return 0;
}

/*
 *	Update the socket async list
 *
 *	Fasync_list locking strategy.
 *
 *	1. fasync_list is modified only under process context socket lock
 *	   i.e. under semaphore.
 *	2. fasync_list is used under read_lock(&sk->sk_callback_lock)
 *	   or under socket lock.
 *	3. fasync_list can be used from softirq context, so that
 *	   modification under socket lock have to be enhanced with
 *	   write_lock_bh(&sk->sk_callback_lock).
 *							--ANK (990710)
 */

static int sock_fasync(int fd, struct file *filp, int on)
{
	struct fasync_struct *fa, *fna=NULL, **prev;
	struct socket *sock;
	struct sock *sk;

	if (on)
	{
		fna=(struct fasync_struct *)kmalloc(sizeof(struct fasync_struct), GFP_KERNEL);
		if(fna==NULL)
			return -ENOMEM;
	}

	sock = SOCKET_I(filp->f_dentry->d_inode);

	if ((sk=sock->sk) == NULL) {
		kfree(fna);
		return -EINVAL;
	}

	lock_sock(sk);

	prev=&(sock->fasync_list);

	for (fa=*prev; fa!=NULL; prev=&fa->fa_next,fa=*prev)
		if (fa->fa_file==filp)
			break;

	if(on)
	{
		if(fa!=NULL)
		{
			write_lock_bh(&sk->sk_callback_lock);
			fa->fa_fd=fd;
			write_unlock_bh(&sk->sk_callback_lock);

			kfree(fna);
			goto out;
		}
		fna->fa_file=filp;
		fna->fa_fd=fd;
		fna->magic=FASYNC_MAGIC;
		fna->fa_next=sock->fasync_list;
		write_lock_bh(&sk->sk_callback_lock);
		sock->fasync_list=fna;
		write_unlock_bh(&sk->sk_callback_lock);
	}
	else
	{
		if (fa!=NULL)
		{
			write_lock_bh(&sk->sk_callback_lock);
			*prev=fa->fa_next;
			write_unlock_bh(&sk->sk_callback_lock);
			kfree(fa);
		}
	}

out:
	release_sock(sock->sk);
	return 0;
}

/* This function may be called only under socket lock or callback_lock */

int sock_wake_async(struct socket *sock, int how, int band)
{
	if (!sock || !sock->fasync_list)
		return -1;
	switch (how)
	{
	case 1:
		
		if (test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
			break;
		goto call_kill;
	case 2:
		if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags))
			break;
		/* fall through */
	case 0:
	call_kill:
		__kill_fasync(sock->fasync_list, SIGIO, band);
		break;
	case 3:
		__kill_fasync(sock->fasync_list, SIGURG, band);
	}
	return 0;
}

static int __sock_create(int family, int type, int protocol, struct socket **res, int kern)
{
	int err;
	struct socket *sock;

	/*
	 *	Check protocol is in range
	 */
	if (family < 0 || family >= NPROTO)
		return -EAFNOSUPPORT;
	if (type < 0 || type >= SOCK_MAX)
		return -EINVAL;

	/* Compatibility.

	   This uglymoron is moved from INET layer to here to avoid
	   deadlock in module load.
	 */
	if (family == PF_INET && type == SOCK_PACKET) {
		static int warned; 
		if (!warned) {
			warned = 1;
			printk(KERN_INFO "%s uses obsolete (PF_INET,SOCK_PACKET)\n", current->comm);
		}
		family = PF_PACKET;
	}

	err = security_socket_create(family, type, protocol, kern);
	if (err)
		return err;
		
#if defined(CONFIG_KMOD)
	/* Attempt to load a protocol module if the find failed. 
	 * 
	 * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user 
	 * requested real, full-featured networking support upon configuration.
	 * Otherwise module support will break!
	 */
	if (net_families[family]==NULL)
	{
		request_module("net-pf-%d",family);
	}
#endif

	net_family_read_lock();
	if (net_families[family] == NULL) {
		err = -EAFNOSUPPORT;
		goto out;
	}

/*
 *	Allocate the socket and allow the family to set things up. if
 *	the protocol is 0, the family is instructed to select an appropriate
 *	default.
 */

	if (!(sock = sock_alloc())) {
		printk(KERN_WARNING "socket: no more sockets\n");
		err = -ENFILE;		/* Not exactly a match, but its the
					   closest posix thing */
		goto out;
	}

	sock->type  = type;

	/*
	 * We will call the ->create function, that possibly is in a loadable
	 * module, so we have to bump that loadable module refcnt first.
	 */
	err = -EAFNOSUPPORT;
	if (!try_module_get(net_families[family]->owner))
		goto out_release;

	if ((err = net_families[family]->create(sock, protocol)) < 0)
		goto out_module_put;
	/*
	 * Now to bump the refcnt of the [loadable] module that owns this
	 * socket at sock_release time we decrement its refcnt.
	 */
	if (!try_module_get(sock->ops->owner)) {
		sock->ops = NULL;
		goto out_module_put;
	}
	/*
	 * Now that we're done with the ->create function, the [loadable]
	 * module can have its refcnt decremented
	 */
	module_put(net_families[family]->owner);
	*res = sock;
	security_socket_post_create(sock, family, type, protocol, kern);

out:
	net_family_read_unlock();
	return err;
out_module_put:
	module_put(net_families[family]->owner);
out_release:
	sock_release(sock);
	goto out;
}

int sock_create(int family, int type, int protocol, struct socket **res)
{
	return __sock_create(family, type, protocol, res, 0);
}

int sock_create_kern(int family, int type, int protocol, struct socket **res)
{
	return __sock_create(family, type, protocol, res, 1);
}

asmlinkage long sys_socket(int family, int type, int protocol)
{
	int retval;
	struct socket *sock;

	retval = sock_create(family, type, protocol, &sock);
	if (retval < 0)
		goto out;

	retval = sock_map_fd(sock);
	if (retval < 0)
		goto out_release;

out:
	/* It may be already another descriptor 8) Not kernel problem. */
	return retval;

out_release:
	sock_release(sock);
	return retval;
}

/*
 *	Create a pair of connected sockets.
 */

asmlinkage long sys_socketpair(int family, int type, int protocol, int __user *usockvec)
{
	struct socket *sock1, *sock2;
	int fd1, fd2, err;

	/*
	 * Obtain the first socket and check if the underlying protocol
	 * supports the socketpair call.
	 */

	err = sock_create(family, type, protocol, &sock1);
	if (err < 0)
		goto out;

	err = sock_create(family, type, protocol, &sock2);
	if (err < 0)
		goto out_release_1;

	err = sock1->ops->socketpair(sock1, sock2);
	if (err < 0) 
		goto out_release_both;

	fd1 = fd2 = -1;

	err = sock_map_fd(sock1);
	if (err < 0)
		goto out_release_both;
	fd1 = err;

	err = sock_map_fd(sock2);
	if (err < 0)
		goto out_close_1;
	fd2 = err;

	/* fd1 and fd2 may be already another descriptors.
	 * Not kernel problem.
	 */

	err = put_user(fd1, &usockvec[0]); 
	if (!err)
		err = put_user(fd2, &usockvec[1]);
	if (!err)
		return 0;

	sys_close(fd2);
	sys_close(fd1);
	return err;

out_close_1:
        sock_release(sock2);
	sys_close(fd1);
	return err;

out_release_both:
        sock_release(sock2);
out_release_1:
        sock_release(sock1);
out:
	return err;
}


/*
 *	Bind a name to a socket. Nothing much to do here since it's
 *	the protocol's responsibility to handle the local address.
 *
 *	We move the socket address to kernel space before we call
 *	the protocol layer (having also checked the address is ok).
 */

asmlinkage long sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	int err;

	if((sock = sockfd_lookup(fd,&err))!=NULL)
	{
		if((err=move_addr_to_kernel(umyaddr,addrlen,address))>=0) {
			err = security_socket_bind(sock, (struct sockaddr *)address, addrlen);
			if (err) {
				sockfd_put(sock);
				return err;
			}
			err = sock->ops->bind(sock, (struct sockaddr *)address, addrlen);
		}
		sockfd_put(sock);
	}			
	return err;
}


/*
 *	Perform a listen. Basically, we allow the protocol to do anything
 *	necessary for a listen, and if that works, we mark the socket as
 *	ready for listening.
 */

int sysctl_somaxconn = SOMAXCONN;

asmlinkage long sys_listen(int fd, int backlog)
{
	struct socket *sock;
	int err;
	
	if ((sock = sockfd_lookup(fd, &err)) != NULL) {
		if ((unsigned) backlog > sysctl_somaxconn)
			backlog = sysctl_somaxconn;

		err = security_socket_listen(sock, backlog);
		if (err) {
			sockfd_put(sock);
			return err;
		}

		err=sock->ops->listen(sock, backlog);
		sockfd_put(sock);
	}
	return err;
}


/*
 *	For accept, we attempt to create a new socket, set up the link
 *	with the client, wake up the client, then return the new
 *	connected fd. We collect the address of the connector in kernel
 *	space and move it to user at the very end. This is unclean because
 *	we open the socket then return an error.
 *
 *	1003.1g adds the ability to recvmsg() to query connection pending
 *	status to recvmsg. We need to add that support in a way thats
 *	clean when we restucture accept also.
 */

asmlinkage long sys_accept(int fd, struct sockaddr __user *upeer_sockaddr, int __user *upeer_addrlen)
{
	struct socket *sock, *newsock;
	int err, len;
	char address[MAX_SOCK_ADDR];

	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;

	err = -ENFILE;
	if (!(newsock = sock_alloc())) 
		goto out_put;

	newsock->type = sock->type;
	newsock->ops = sock->ops;

	err = security_socket_accept(sock, newsock);
	if (err)
		goto out_release;

	/*
	 * We don't need try_module_get here, as the listening socket (sock)
	 * has the protocol module (sock->ops->owner) held.
	 */
	__module_get(newsock->ops->owner);

	err = sock->ops->accept(sock, newsock, sock->file->f_flags);
	if (err < 0)
		goto out_release;

	if (upeer_sockaddr) {
		if(newsock->ops->getname(newsock, (struct sockaddr *)address, &len, 2)<0) {
			err = -ECONNABORTED;
			goto out_release;
		}
		err = move_addr_to_user(address, len, upeer_sockaddr, upeer_addrlen);
		if (err < 0)
			goto out_release;
	}

	/* File flags are not inherited via accept() unlike another OSes. */

	if ((err = sock_map_fd(newsock)) < 0)
		goto out_release;

	security_socket_post_accept(sock, newsock);

out_put:
	sockfd_put(sock);
out:
	return err;
out_release:
	sock_release(newsock);
	goto out_put;
}


/*
 *	Attempt to connect to a socket with the server address.  The address
 *	is in user space so we verify it is OK and move it to kernel space.
 *
 *	For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
 *	break bindings
 *
 *	NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
 *	other SEQPACKET protocols that take time to connect() as it doesn't
 *	include the -EINPROGRESS status for such sockets.
 */

asmlinkage long sys_connect(int fd, struct sockaddr __user *uservaddr, int addrlen)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	int err;

	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;
	err = move_addr_to_kernel(uservaddr, addrlen, address);
	if (err < 0)
		goto out_put;

	err = security_socket_connect(sock, (struct sockaddr *)address, addrlen);
	if (err)
		goto out_put;

	err = sock->ops->connect(sock, (struct sockaddr *) address, addrlen,
				 sock->file->f_flags);
out_put:
	sockfd_put(sock);
out:
	return err;
}

/*
 *	Get the local address ('name') of a socket object. Move the obtained
 *	name to user space.
 */

asmlinkage long sys_getsockname(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	int len, err;
	
	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;

	err = security_socket_getsockname(sock);
	if (err)
		goto out_put;

	err = sock->ops->getname(sock, (struct sockaddr *)address, &len, 0);
	if (err)
		goto out_put;
	err = move_addr_to_user(address, len, usockaddr, usockaddr_len);

out_put:
	sockfd_put(sock);
out:
	return err;
}

/*
 *	Get the remote address ('name') of a socket object. Move the obtained
 *	name to user space.
 */

asmlinkage long sys_getpeername(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	int len, err;

	if ((sock = sockfd_lookup(fd, &err))!=NULL)
	{
		err = security_socket_getpeername(sock);
		if (err) {
			sockfd_put(sock);
			return err;
		}

		err = sock->ops->getname(sock, (struct sockaddr *)address, &len, 1);
		if (!err)
			err=move_addr_to_user(address,len, usockaddr, usockaddr_len);
		sockfd_put(sock);
	}
	return err;
}

/*
 *	Send a datagram to a given address. We move the address into kernel
 *	space and check the user space data area is readable before invoking
 *	the protocol.
 */

asmlinkage long sys_sendto(int fd, void __user * buff, size_t len, unsigned flags,
			   struct sockaddr __user *addr, int addr_len)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	int err;
	struct msghdr msg;
	struct iovec iov;
	
	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;
	iov.iov_base=buff;
	iov.iov_len=len;
	msg.msg_name=NULL;
	msg.msg_iov=&iov;
	msg.msg_iovlen=1;
	msg.msg_control=NULL;
	msg.msg_controllen=0;
	msg.msg_namelen=0;
	if(addr)
	{
		err = move_addr_to_kernel(addr, addr_len, address);
		if (err < 0)
			goto out_put;
		msg.msg_name=address;
		msg.msg_namelen=addr_len;
	}
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
	msg.msg_flags = flags;
	err = sock_sendmsg(sock, &msg, len);

out_put:		
	sockfd_put(sock);
out:
	return err;
}

/*
 *	Send a datagram down a socket. 
 */

asmlinkage long sys_send(int fd, void __user * buff, size_t len, unsigned flags)
{
	return sys_sendto(fd, buff, len, flags, NULL, 0);
}

/*
 *	Receive a frame from the socket and optionally record the address of the 
 *	sender. We verify the buffers are writable and if needed move the
 *	sender address from kernel to user space.
 */

asmlinkage long sys_recvfrom(int fd, void __user * ubuf, size_t size, unsigned flags,
			     struct sockaddr __user *addr, int __user *addr_len)
{
	struct socket *sock;
	struct iovec iov;
	struct msghdr msg;
	char address[MAX_SOCK_ADDR];
	int err,err2;

	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;

	msg.msg_control=NULL;
	msg.msg_controllen=0;
	msg.msg_iovlen=1;
	msg.msg_iov=&iov;
	iov.iov_len=size;
	iov.iov_base=ubuf;
	msg.msg_name=address;
	msg.msg_namelen=MAX_SOCK_ADDR;
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
	err=sock_recvmsg(sock, &msg, size, flags);

	if(err >= 0 && addr != NULL)
	{
		err2=move_addr_to_user(address, msg.msg_namelen, addr, addr_len);
		if(err2<0)
			err=err2;
	}
	sockfd_put(sock);			
out:
	return err;
}

/*
 *	Receive a datagram from a socket. 
 */

asmlinkage long sys_recv(int fd, void __user * ubuf, size_t size, unsigned flags)
{
	return sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
}

/*
 *	Set a socket option. Because we don't know the option lengths we have
 *	to pass the user mode parameter for the protocols to sort out.
 */

asmlinkage long sys_setsockopt(int fd, int level, int optname, char __user *optval, int optlen)
{
	int err;
	struct socket *sock;

	if (optlen < 0)
		return -EINVAL;
			
	if ((sock = sockfd_lookup(fd, &err))!=NULL)
	{
		err = security_socket_setsockopt(sock,level,optname);
		if (err) {
			sockfd_put(sock);
			return err;
		}

		if (level == SOL_SOCKET)
			err=sock_setsockopt(sock,level,optname,optval,optlen);
		else
			err=sock->ops->setsockopt(sock, level, optname, optval, optlen);
		sockfd_put(sock);
	}
	return err;
}

/*
 *	Get a socket option. Because we don't know the option lengths we have
 *	to pass a user mode parameter for the protocols to sort out.
 */

asmlinkage long sys_getsockopt(int fd, int level, int optname, char __user *optval, int __user *optlen)
{
	int err;
	struct socket *sock;

	if ((sock = sockfd_lookup(fd, &err))!=NULL)
	{
		err = security_socket_getsockopt(sock, level, 
							   optname);
		if (err) {
			sockfd_put(sock);
			return err;
		}

		if (level == SOL_SOCKET)
			err=sock_getsockopt(sock,level,optname,optval,optlen);
		else
			err=sock->ops->getsockopt(sock, level, optname, optval, optlen);
		sockfd_put(sock);
	}
	return err;
}


/*
 *	Shutdown a socket.
 */

asmlinkage long sys_shutdown(int fd, int how)
{
	int err;
	struct socket *sock;

	if ((sock = sockfd_lookup(fd, &err))!=NULL)
	{
		err = security_socket_shutdown(sock, how);
		if (err) {
			sockfd_put(sock);
			return err;
		}
				
		err=sock->ops->shutdown(sock, how);
		sockfd_put(sock);
	}
	return err;
}

/* A couple of helpful macros for getting the address of the 32/64 bit 
 * fields which are the same type (int / unsigned) on our platforms.
 */
#define COMPAT_MSG(msg, member)	((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
#define COMPAT_NAMELEN(msg)	COMPAT_MSG(msg, msg_namelen)
#define COMPAT_FLAGS(msg)	COMPAT_MSG(msg, msg_flags)


/*
 *	BSD sendmsg interface
 */

asmlinkage long sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags)
{
	struct compat_msghdr __user *msg_compat = (struct compat_msghdr __user *)msg;
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
	unsigned char ctl[sizeof(struct cmsghdr) + 20];	/* 20 is size of ipv6_pktinfo */
	unsigned char *ctl_buf = ctl;
	struct msghdr msg_sys;
	int err, ctl_len, iov_size, total_len;
	
	err = -EFAULT;
	if (MSG_CMSG_COMPAT & flags) {
		if (get_compat_msghdr(&msg_sys, msg_compat))
			return -EFAULT;
	} else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
		return -EFAULT;

	sock = sockfd_lookup(fd, &err);
	if (!sock) 
		goto out;

	/* do not move before msg_sys is valid */
	err = -EMSGSIZE;
	if (msg_sys.msg_iovlen > UIO_MAXIOV)
		goto out_put;

	/* Check whether to allocate the iovec area*/
	err = -ENOMEM;
	iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
	if (msg_sys.msg_iovlen > UIO_FASTIOV) {
		iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
		if (!iov)
			goto out_put;
	}

	/* This will also move the address data into kernel space */
	if (MSG_CMSG_COMPAT & flags) {
		err = verify_compat_iovec(&msg_sys, iov, address, VERIFY_READ);
	} else
		err = verify_iovec(&msg_sys, iov, address, VERIFY_READ);
	if (err < 0) 
		goto out_freeiov;
	total_len = err;

	err = -ENOBUFS;

	if (msg_sys.msg_controllen > INT_MAX)
		goto out_freeiov;
	ctl_len = msg_sys.msg_controllen; 
	if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
		err = cmsghdr_from_user_compat_to_kern(&msg_sys, ctl, sizeof(ctl));
		if (err)
			goto out_freeiov;
		ctl_buf = msg_sys.msg_control;
	} else if (ctl_len) {
		if (ctl_len > sizeof(ctl))
		{
			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
			if (ctl_buf == NULL) 
				goto out_freeiov;
		}
		err = -EFAULT;
		/*
		 * Careful! Before this, msg_sys.msg_control contains a user pointer.
		 * Afterwards, it will be a kernel pointer. Thus the compiler-assisted
		 * checking falls down on this.
		 */
		if (copy_from_user(ctl_buf, (void __user *) msg_sys.msg_control, ctl_len))
			goto out_freectl;
		msg_sys.msg_control = ctl_buf;
	}
	msg_sys.msg_flags = flags;

	if (sock->file->f_flags & O_NONBLOCK)
		msg_sys.msg_flags |= MSG_DONTWAIT;
	err = sock_sendmsg(sock, &msg_sys, total_len);

out_freectl:
	if (ctl_buf != ctl)    
		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
out_freeiov:
	if (iov != iovstack)
		sock_kfree_s(sock->sk, iov, iov_size);
out_put:
	sockfd_put(sock);
out:       
	return err;
}

/*
 *	BSD recvmsg interface
 */

asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg, unsigned int flags)
{
	struct compat_msghdr __user *msg_compat = (struct compat_msghdr __user *)msg;
	struct socket *sock;
	struct iovec iovstack[UIO_FASTIOV];
	struct iovec *iov=iovstack;
	struct msghdr msg_sys;
	unsigned long cmsg_ptr;
	int err, iov_size, total_len, len;

	/* kernel mode address */
	char addr[MAX_SOCK_ADDR];

	/* user mode address pointers */
	struct sockaddr __user *uaddr;
	int __user *uaddr_len;
	
	if (MSG_CMSG_COMPAT & flags) {
		if (get_compat_msghdr(&msg_sys, msg_compat))
			return -EFAULT;
	} else
		if (copy_from_user(&msg_sys,msg,sizeof(struct msghdr)))
			return -EFAULT;

	sock = sockfd_lookup(fd, &err);
	if (!sock)
		goto out;

	err = -EMSGSIZE;
	if (msg_sys.msg_iovlen > UIO_MAXIOV)
		goto out_put;
	
	/* Check whether to allocate the iovec area*/
	err = -ENOMEM;
	iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
	if (msg_sys.msg_iovlen > UIO_FASTIOV) {
		iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
		if (!iov)
			goto out_put;
	}

	/*
	 *	Save the user-mode address (verify_iovec will change the
	 *	kernel msghdr to use the kernel address space)
	 */
	 
	uaddr = (void __user *) msg_sys.msg_name;
	uaddr_len = COMPAT_NAMELEN(msg);
	if (MSG_CMSG_COMPAT & flags) {
		err = verify_compat_iovec(&msg_sys, iov, addr, VERIFY_WRITE);
	} else
		err = verify_iovec(&msg_sys, iov, addr, VERIFY_WRITE);
	if (err < 0)
		goto out_freeiov;
	total_len=err;

	cmsg_ptr = (unsigned long)msg_sys.msg_control;
	msg_sys.msg_flags = 0;
	if (MSG_CMSG_COMPAT & flags)
		msg_sys.msg_flags = MSG_CMSG_COMPAT;
	
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
	err = sock_recvmsg(sock, &msg_sys, total_len, flags);
	if (err < 0)
		goto out_freeiov;
	len = err;

	if (uaddr != NULL) {
		err = move_addr_to_user(addr, msg_sys.msg_namelen, uaddr, uaddr_len);
		if (err < 0)
			goto out_freeiov;
	}
	err = __put_user(msg_sys.msg_flags, COMPAT_FLAGS(msg));
	if (err)
		goto out_freeiov;
	if (MSG_CMSG_COMPAT & flags)
		err = __put_user((unsigned long)msg_sys.msg_control-cmsg_ptr, 
				 &msg_compat->msg_controllen);
	else
		err = __put_user((unsigned long)msg_sys.msg_control-cmsg_ptr, 
				 &msg->msg_controllen);
	if (err)
		goto out_freeiov;
	err = len;

out_freeiov:
	if (iov != iovstack)
		sock_kfree_s(sock->sk, iov, iov_size);
out_put:
	sockfd_put(sock);
out:
	return err;
}

#ifdef __ARCH_WANT_SYS_SOCKETCALL

/* Argument list sizes for sys_socketcall */
#define AL(x) ((x) * sizeof(unsigned long))
static unsigned char nargs[18]={AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
				AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
				AL(6),AL(2),AL(5),AL(5),AL(3),AL(3)};
#undef AL

/*
 *	System call vectors. 
 *
 *	Argument checking cleaned up. Saved 20% in size.
 *  This function doesn't need to set the kernel lock because
 *  it is set by the callees. 
 */

asmlinkage long sys_socketcall(int call, unsigned long __user *args)
{
	unsigned long a[6];
	unsigned long a0,a1;
	int err;

	if(call<1||call>SYS_RECVMSG)
		return -EINVAL;

	/* copy_from_user should be SMP safe. */
	if (copy_from_user(a, args, nargs[call]))
		return -EFAULT;

	err = audit_socketcall(nargs[call]/sizeof(unsigned long), a);
	if (err)
		return err;

	a0=a[0];
	a1=a[1];
	
	switch(call) 
	{
		case SYS_SOCKET:
			err = sys_socket(a0,a1,a[2]);
			break;
		case SYS_BIND:
			err = sys_bind(a0,(struct sockaddr __user *)a1, a[2]);
			break;
		case SYS_CONNECT:
			err = sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
			break;
		case SYS_LISTEN:
			err = sys_listen(a0,a1);
			break;
		case SYS_ACCEPT:
			err = sys_accept(a0,(struct sockaddr __user *)a1, (int __user *)a[2]);
			break;
		case SYS_GETSOCKNAME:
			err = sys_getsockname(a0,(struct sockaddr __user *)a1, (int __user *)a[2]);
			break;
		case SYS_GETPEERNAME:
			err = sys_getpeername(a0, (struct sockaddr __user *)a1, (int __user *)a[2]);
			break;
		case SYS_SOCKETPAIR:
			err = sys_socketpair(a0,a1, a[2], (int __user *)a[3]);
			break;
		case SYS_SEND:
			err = sys_send(a0, (void __user *)a1, a[2], a[3]);
			break;
		case SYS_SENDTO:
			err = sys_sendto(a0,(void __user *)a1, a[2], a[3],
					 (struct sockaddr __user *)a[4], a[5]);
			break;
		case SYS_RECV:
			err = sys_recv(a0, (void __user *)a1, a[2], a[3]);
			break;
		case SYS_RECVFROM:
			err = sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
					   (struct sockaddr __user *)a[4], (int __user *)a[5]);
			break;
		case SYS_SHUTDOWN:
			err = sys_shutdown(a0,a1);
			break;
		case SYS_SETSOCKOPT:
			err = sys_setsockopt(a0, a1, a[2], (char __user *)a[3], a[4]);
			break;
		case SYS_GETSOCKOPT:
			err = sys_getsockopt(a0, a1, a[2], (char __user *)a[3], (int __user *)a[4]);
			break;
		case SYS_SENDMSG:
			err = sys_sendmsg(a0, (struct msghdr __user *) a1, a[2]);
			break;
		case SYS_RECVMSG:
			err = sys_recvmsg(a0, (struct msghdr __user *) a1, a[2]);
			break;
		default:
			err = -EINVAL;
			break;
	}
	return err;
}

#endif /* __ARCH_WANT_SYS_SOCKETCALL */

/*
 *	This function is called by a protocol handler that wants to
 *	advertise its address family, and have it linked into the
 *	SOCKET module.
 */

int sock_register(struct net_proto_family *ops)
{
	int err;

	if (ops->family >= NPROTO) {
		printk(KERN_CRIT "protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
		return -ENOBUFS;
	}
	net_family_write_lock();
	err = -EEXIST;
	if (net_families[ops->family] == NULL) {
		net_families[ops->family]=ops;
		err = 0;
	}
	net_family_write_unlock();
	printk(KERN_INFO "NET: Registered protocol family %d\n",
	       ops->family);
	return err;
}

/*
 *	This function is called by a protocol handler that wants to
 *	remove its address family, and have it unlinked from the
 *	SOCKET module.
 */

int sock_unregister(int family)
{
	if (family < 0 || family >= NPROTO)
		return -1;

	net_family_write_lock();
	net_families[family]=NULL;
	net_family_write_unlock();
	printk(KERN_INFO "NET: Unregistered protocol family %d\n",
	       family);
	return 0;
}


extern void sk_init(void);

void __init sock_init(void)
{
	/*
	 *	Initialize sock SLAB cache.
	 */
	 
	sk_init();

#ifdef SLAB_SKB
	/*
	 *	Initialize skbuff SLAB cache 
	 */
	skb_init();
#endif

	/*
	 *	Initialize the protocols module. 
	 */

	init_inodecache();
	register_filesystem(&sock_fs_type);
	sock_mnt = kern_mount(&sock_fs_type);
	/* The real protocol initialization is performed when
	 *  do_initcalls is run.  
	 */

#ifdef CONFIG_NETFILTER
	netfilter_init();
#endif
}

#ifdef CONFIG_PROC_FS
void socket_seq_show(struct seq_file *seq)
{
	int cpu;
	int counter = 0;

	for (cpu = 0; cpu < NR_CPUS; cpu++)
		counter += per_cpu(sockets_in_use, cpu);

	/* It can be negative, by the way. 8) */
	if (counter < 0)
		counter = 0;

	seq_printf(seq, "sockets: used %d\n", counter);
}
#endif /* CONFIG_PROC_FS */

/* ABI emulation layers need these two */
EXPORT_SYMBOL(move_addr_to_kernel);
EXPORT_SYMBOL(move_addr_to_user);
EXPORT_SYMBOL(sock_create);
EXPORT_SYMBOL(sock_create_kern);
EXPORT_SYMBOL(sock_create_lite);
EXPORT_SYMBOL(sock_map_fd);
EXPORT_SYMBOL(sock_recvmsg);
EXPORT_SYMBOL(sock_register);
EXPORT_SYMBOL(sock_release);
EXPORT_SYMBOL(sock_sendmsg);
EXPORT_SYMBOL(sock_unregister);
EXPORT_SYMBOL(sock_wake_async);
EXPORT_SYMBOL(sockfd_lookup);
EXPORT_SYMBOL(kernel_sendmsg);
EXPORT_SYMBOL(kernel_recvmsg);