net/core/sock.c

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              Generic socket support routines. Memory allocators, socket lock/release
   7  *              handler for protocols to use and generic option handler.
   8  *
   9  *
  10  * Version:     $Id: sock.c,v 1.117 2002/02/01 22:01:03 davem Exp $
  11  *
  12  * Authors:     Ross Biro, <bir7@leland.Stanford.Edu>
  13  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  14  *              Florian La Roche, <flla@stud.uni-sb.de>
  15  *              Alan Cox, <A.Cox@swansea.ac.uk>
  16  *
  17  * Fixes:
  18  *              Alan Cox        :       Numerous verify_area() problems
  19  *              Alan Cox        :       Connecting on a connecting socket
  20  *                                      now returns an error for tcp.
  21  *              Alan Cox        :       sock->protocol is set correctly.
  22  *                                      and is not sometimes left as 0.
  23  *              Alan Cox        :       connect handles icmp errors on a
  24  *                                      connect properly. Unfortunately there
  25  *                                      is a restart syscall nasty there. I
  26  *                                      can't match BSD without hacking the C
  27  *                                      library. Ideas urgently sought!
  28  *              Alan Cox        :       Disallow bind() to addresses that are
  29  *                                      not ours - especially broadcast ones!!
  30  *              Alan Cox        :       Socket 1024 _IS_ ok for users. (fencepost)
  31  *              Alan Cox        :       sock_wfree/sock_rfree don't destroy sockets,
  32  *                                      instead they leave that for the DESTROY timer.
  33  *              Alan Cox        :       Clean up error flag in accept
  34  *              Alan Cox        :       TCP ack handling is buggy, the DESTROY timer
  35  *                                      was buggy. Put a remove_sock() in the handler
  36  *                                      for memory when we hit 0. Also altered the timer
  37  *                                      code. The ACK stuff can wait and needs major
  38  *                                      TCP layer surgery.
  39  *              Alan Cox        :       Fixed TCP ack bug, removed remove sock
  40  *                                      and fixed timer/inet_bh race.
  41  *              Alan Cox        :       Added zapped flag for TCP
  42  *              Alan Cox        :       Move kfree_skb into skbuff.c and tidied up surplus code
  43  *              Alan Cox        :       for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
  44  *              Alan Cox        :       kfree_s calls now are kfree_skbmem so we can track skb resources
  45  *              Alan Cox        :       Supports socket option broadcast now as does udp. Packet and raw need fixing.
  46  *              Alan Cox        :       Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
  47  *              Rick Sladkey    :       Relaxed UDP rules for matching packets.
  48  *              C.E.Hawkins     :       IFF_PROMISC/SIOCGHWADDR support
  49  *      Pauline Middelink       :       identd support
  50  *              Alan Cox        :       Fixed connect() taking signals I think.
  51  *              Alan Cox        :       SO_LINGER supported
  52  *              Alan Cox        :       Error reporting fixes
  53  *              Anonymous       :       inet_create tidied up (sk->reuse setting)
  54  *              Alan Cox        :       inet sockets don't set sk->type!
  55  *              Alan Cox        :       Split socket option code
  56  *              Alan Cox        :       Callbacks
  57  *              Alan Cox        :       Nagle flag for Charles & Johannes stuff
  58  *              Alex            :       Removed restriction on inet fioctl
  59  *              Alan Cox        :       Splitting INET from NET core
  60  *              Alan Cox        :       Fixed bogus SO_TYPE handling in getsockopt()
  61  *              Adam Caldwell   :       Missing return in SO_DONTROUTE/SO_DEBUG code
  62  *              Alan Cox        :       Split IP from generic code
  63  *              Alan Cox        :       New kfree_skbmem()
  64  *              Alan Cox        :       Make SO_DEBUG superuser only.
  65  *              Alan Cox        :       Allow anyone to clear SO_DEBUG
  66  *                                      (compatibility fix)
  67  *              Alan Cox        :       Added optimistic memory grabbing for AF_UNIX throughput.
  68  *              Alan Cox        :       Allocator for a socket is settable.
  69  *              Alan Cox        :       SO_ERROR includes soft errors.
  70  *              Alan Cox        :       Allow NULL arguments on some SO_ opts
  71  *              Alan Cox        :       Generic socket allocation to make hooks
  72  *                                      easier (suggested by Craig Metz).
  73  *              Michael Pall    :       SO_ERROR returns positive errno again
  74  *              Steve Whitehouse:       Added default destructor to free
  75  *                                      protocol private data.
  76  *              Steve Whitehouse:       Added various other default routines
  77  *                                      common to several socket families.
  78  *              Chris Evans     :       Call suser() check last on F_SETOWN
  79  *              Jay Schulist    :       Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
  80  *              Andi Kleen      :       Add sock_kmalloc()/sock_kfree_s()
  81  *              Andi Kleen      :       Fix write_space callback
  82  *              Chris Evans     :       Security fixes - signedness again
  83  *              Arnaldo C. Melo :       cleanups, use skb_queue_purge
  84  *
  85  * To Fix:
  86  *
  87  *
  88  *              This program is free software; you can redistribute it and/or
  89  *              modify it under the terms of the GNU General Public License
  90  *              as published by the Free Software Foundation; either version
  91  *              2 of the License, or (at your option) any later version.
  92  */
  93
  94 #include <linux/config.h>
  95 #include <linux/errno.h>
  96 #include <linux/types.h>
  97 #include <linux/socket.h>
  98 #include <linux/in.h>
  99 #include <linux/kernel.h>
 100 #include <linux/major.h>
 101 #include <linux/module.h>
 102 #include <linux/sched.h>
 103 #include <linux/timer.h>
 104 #include <linux/string.h>
 105 #include <linux/sockios.h>
 106 #include <linux/net.h>
 107 #include <linux/mm.h>
 108 #include <linux/slab.h>
 109 #include <linux/interrupt.h>
 110 #include <linux/poll.h>
 111 #include <linux/tcp.h>
 112 #include <linux/init.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/sock.h>
 121 #include <net/xfrm.h>
 122 #include <linux/ipsec.h>
 123
 124 #include <linux/filter.h>
 125
 126 #ifdef CONFIG_INET
 127 #include <net/tcp.h>
 128 #endif
 129
 130 /* Take into consideration the size of the struct sk_buff overhead in the
 131  * determination of these values, since that is non-constant across
 132  * platforms.  This makes socket queueing behavior and performance
 133  * not depend upon such differences.
 134  */
 135 #define _SK_MEM_PACKETS         256
 136 #define _SK_MEM_OVERHEAD        (sizeof(struct sk_buff) + 256)
 137 #define SK_WMEM_MAX             (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
 138 #define SK_RMEM_MAX             (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
 139
 140 /* Run time adjustable parameters. */
 141 __u32 sysctl_wmem_max = SK_WMEM_MAX;
 142 __u32 sysctl_rmem_max = SK_RMEM_MAX;
 143 __u32 sysctl_wmem_default = SK_WMEM_MAX;
 144 __u32 sysctl_rmem_default = SK_RMEM_MAX;
 145
 146 /* Maximal space eaten by iovec or ancilliary data plus some space */
 147 int sysctl_optmem_max = sizeof(unsigned long)*(2*UIO_MAXIOV + 512);
 148
 149 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
 150 {
 151         struct timeval tv;
 152
 153         if (optlen < sizeof(tv))
 154                 return -EINVAL;
 155         if (copy_from_user(&tv, optval, sizeof(tv)))
 156                 return -EFAULT;
 157
 158         *timeo_p = MAX_SCHEDULE_TIMEOUT;
 159         if (tv.tv_sec == 0 && tv.tv_usec == 0)
 160                 return 0;
 161         if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
 162                 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
 163         return 0;
 164 }
 165
 166 static void sock_warn_obsolete_bsdism(const char *name)
 167 {
 168         static int warned;
 169         static char warncomm[16];
 170         if (strcmp(warncomm, current->comm) && warned < 5) {
 171                 strcpy(warncomm,  current->comm);
 172                 printk(KERN_WARNING "process `%s' is using obsolete "
 173                        "%s SO_BSDCOMPAT\n", warncomm, name);
 174                 warned++;
 175         }
 176 }
 177
 178 static void sock_disable_timestamp(struct sock *sk)
 179 {
 180         if (sock_flag(sk, SOCK_TIMESTAMP)) {
 181                 sock_reset_flag(sk, SOCK_TIMESTAMP);
 182                 net_disable_timestamp();
 183         }
 184 }
 185
 186
 187 /*
 188  *      This is meant for all protocols to use and covers goings on
 189  *      at the socket level. Everything here is generic.
 190  */
 191
 192 int sock_setsockopt(struct socket *sock, int level, int optname,
 193                     char __user *optval, int optlen)
 194 {
 195         struct sock *sk=sock->sk;
 196         struct sk_filter *filter;
 197         int val;
 198         int valbool;
 199         struct linger ling;
 200         int ret = 0;
 201
 202         /*
 203          *      Options without arguments
 204          */
 205
 206 #ifdef SO_DONTLINGER            /* Compatibility item... */
 207         switch (optname) {
 208                 case SO_DONTLINGER:
 209                         sock_reset_flag(sk, SOCK_LINGER);
 210                         return 0;
 211         }
 212 #endif
 213
 214         if(optlen<sizeof(int))
 215                 return(-EINVAL);
 216
 217         if (get_user(val, (int __user *)optval))
 218                 return -EFAULT;
 219
 220         valbool = val?1:0;
 221
 222         lock_sock(sk);
 223
 224         switch(optname)
 225         {
 226                 case SO_DEBUG:
 227                         if(val && !capable(CAP_NET_ADMIN))
 228                         {
 229                                 ret = -EACCES;
 230                         }
 231                         else
 232                                 sk->sk_debug = valbool;
 233                         break;
 234                 case SO_REUSEADDR:
 235                         sk->sk_reuse = valbool;
 236                         break;
 237                 case SO_TYPE:
 238                 case SO_ERROR:
 239                         ret = -ENOPROTOOPT;
 240                         break;
 241                 case SO_DONTROUTE:
 242                         sk->sk_localroute = valbool;
 243                         break;
 244                 case SO_BROADCAST:
 245                         sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
 246                         break;
 247                 case SO_SNDBUF:
 248                         /* Don't error on this BSD doesn't and if you think
 249                            about it this is right. Otherwise apps have to
 250                            play 'guess the biggest size' games. RCVBUF/SNDBUF
 251                            are treated in BSD as hints */
 252
 253                         if (val > sysctl_wmem_max)
 254                                 val = sysctl_wmem_max;
 255
 256                         sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
 257                         if ((val * 2) < SOCK_MIN_SNDBUF)
 258                                 sk->sk_sndbuf = SOCK_MIN_SNDBUF;
 259                         else
 260                                 sk->sk_sndbuf = val * 2;
 261
 262                         /*
 263                          *      Wake up sending tasks if we
 264                          *      upped the value.
 265                          */
 266                         sk->sk_write_space(sk);
 267                         break;
 268
 269                 case SO_RCVBUF:
 270                         /* Don't error on this BSD doesn't and if you think
 271                            about it this is right. Otherwise apps have to
 272                            play 'guess the biggest size' games. RCVBUF/SNDBUF
 273                            are treated in BSD as hints */
 274
 275                         if (val > sysctl_rmem_max)
 276                                 val = sysctl_rmem_max;
 277
 278                         sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 279                         /* FIXME: is this lower bound the right one? */
 280                         if ((val * 2) < SOCK_MIN_RCVBUF)
 281                                 sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
 282                         else
 283                                 sk->sk_rcvbuf = val * 2;
 284                         break;
 285
 286                 case SO_KEEPALIVE:
 287 #ifdef CONFIG_INET
 288                         if (sk->sk_protocol == IPPROTO_TCP)
 289                                 tcp_set_keepalive(sk, valbool);
 290 #endif
 291                         sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
 292                         break;
 293
 294                 case SO_OOBINLINE:
 295                         sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
 296                         break;
 297
 298                 case SO_NO_CHECK:
 299                         sk->sk_no_check = valbool;
 300                         break;
 301
 302                 case SO_PRIORITY:
 303                         if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
 304                                 sk->sk_priority = val;
 305                         else
 306                                 ret = -EPERM;
 307                         break;
 308
 309                 case SO_LINGER:
 310                         if(optlen<sizeof(ling)) {
 311                                 ret = -EINVAL;  /* 1003.1g */
 312                                 break;
 313                         }
 314                         if (copy_from_user(&ling,optval,sizeof(ling))) {
 315                                 ret = -EFAULT;
 316                                 break;
 317                         }
 318                         if (!ling.l_onoff)
 319                                 sock_reset_flag(sk, SOCK_LINGER);
 320                         else {
 321 #if (BITS_PER_LONG == 32)
 322                                 if (ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
 323                                         sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
 324                                 else
 325 #endif
 326                                         sk->sk_lingertime = ling.l_linger * HZ;
 327                                 sock_set_flag(sk, SOCK_LINGER);
 328                         }
 329                         break;
 330
 331                 case SO_BSDCOMPAT:
 332                         sock_warn_obsolete_bsdism("setsockopt");
 333                         break;
 334
 335                 case SO_PASSCRED:
 336                         sock->passcred = valbool;
 337                         break;
 338
 339                 case SO_TIMESTAMP:
 340                         sk->sk_rcvtstamp = valbool;
 341                         if (valbool)
 342                                 sock_enable_timestamp(sk);
 343                         break;
 344
 345                 case SO_RCVLOWAT:
 346                         if (val < 0)
 347                                 val = INT_MAX;
 348                         sk->sk_rcvlowat = val ? : 1;
 349                         break;
 350
 351                 case SO_RCVTIMEO:
 352                         ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
 353                         break;
 354
 355                 case SO_SNDTIMEO:
 356                         ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
 357                         break;
 358
 359 #ifdef CONFIG_NETDEVICES
 360                 case SO_BINDTODEVICE:
 361                 {
 362                         char devname[IFNAMSIZ];
 363
 364                         /* Sorry... */
 365                         if (!capable(CAP_NET_RAW)) {
 366                                 ret = -EPERM;
 367                                 break;
 368                         }
 369
 370                         /* Bind this socket to a particular device like "eth0",
 371                          * as specified in the passed interface name. If the
 372                          * name is "" or the option length is zero the socket
 373                          * is not bound.
 374                          */
 375
 376                         if (!valbool) {
 377                                 sk->sk_bound_dev_if = 0;
 378                         } else {
 379                                 if (optlen > IFNAMSIZ)
 380                                         optlen = IFNAMSIZ;
 381                                 if (copy_from_user(devname, optval, optlen)) {
 382                                         ret = -EFAULT;
 383                                         break;
 384                                 }
 385
 386                                 /* Remove any cached route for this socket. */
 387                                 sk_dst_reset(sk);
 388
 389                                 if (devname[0] == '\0') {
 390                                         sk->sk_bound_dev_if = 0;
 391                                 } else {
 392                                         struct net_device *dev = dev_get_by_name(devname);
 393                                         if (!dev) {
 394                                                 ret = -ENODEV;
 395                                                 break;
 396                                         }
 397                                         sk->sk_bound_dev_if = dev->ifindex;
 398                                         dev_put(dev);
 399                                 }
 400                         }
 401                         break;
 402                 }
 403 #endif
 404
 405
 406                 case SO_ATTACH_FILTER:
 407                         ret = -EINVAL;
 408                         if (optlen == sizeof(struct sock_fprog)) {
 409                                 struct sock_fprog fprog;
 410
 411                                 ret = -EFAULT;
 412                                 if (copy_from_user(&fprog, optval, sizeof(fprog)))
 413                                         break;
 414
 415                                 ret = sk_attach_filter(&fprog, sk);
 416                         }
 417                         break;
 418
 419                 case SO_DETACH_FILTER:
 420                         spin_lock_bh(&sk->sk_lock.slock);
 421                         filter = sk->sk_filter;
 422                         if (filter) {
 423                                 sk->sk_filter = NULL;
 424                                 spin_unlock_bh(&sk->sk_lock.slock);
 425                                 sk_filter_release(sk, filter);
 426                                 break;
 427                         }
 428                         spin_unlock_bh(&sk->sk_lock.slock);
 429                         ret = -ENONET;
 430                         break;
 431
 432                 /* We implement the SO_SNDLOWAT etc to
 433                    not be settable (1003.1g 5.3) */
 434                 default:
 435                         ret = -ENOPROTOOPT;
 436                         break;
 437         }
 438         release_sock(sk);
 439         return ret;
 440 }
 441
 442
 443 int sock_getsockopt(struct socket *sock, int level, int optname,
 444                     char __user *optval, int __user *optlen)
 445 {
 446         struct sock *sk = sock->sk;
 447
 448         union
 449         {
 450                 int val;
 451                 struct linger ling;
 452                 struct timeval tm;
 453         } v;
 454
 455         unsigned int lv = sizeof(int);
 456         int len;
 457
 458         if(get_user(len,optlen))
 459                 return -EFAULT;
 460         if(len < 0)
 461                 return -EINVAL;
 462
 463         switch(optname)
 464         {
 465                 case SO_DEBUG:
 466                         v.val = sk->sk_debug;
 467                         break;
 468
 469                 case SO_DONTROUTE:
 470                         v.val = sk->sk_localroute;
 471                         break;
 472
 473                 case SO_BROADCAST:
 474                         v.val = !!sock_flag(sk, SOCK_BROADCAST);
 475                         break;
 476
 477                 case SO_SNDBUF:
 478                         v.val = sk->sk_sndbuf;
 479                         break;
 480
 481                 case SO_RCVBUF:
 482                         v.val = sk->sk_rcvbuf;
 483                         break;
 484
 485                 case SO_REUSEADDR:
 486                         v.val = sk->sk_reuse;
 487                         break;
 488
 489                 case SO_KEEPALIVE:
 490                         v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
 491                         break;
 492
 493                 case SO_TYPE:
 494                         v.val = sk->sk_type;
 495                         break;
 496
 497                 case SO_ERROR:
 498                         v.val = -sock_error(sk);
 499                         if(v.val==0)
 500                                 v.val = xchg(&sk->sk_err_soft, 0);
 501                         break;
 502
 503                 case SO_OOBINLINE:
 504                         v.val = !!sock_flag(sk, SOCK_URGINLINE);
 505                         break;
 506
 507                 case SO_NO_CHECK:
 508                         v.val = sk->sk_no_check;
 509                         break;
 510
 511                 case SO_PRIORITY:
 512                         v.val = sk->sk_priority;
 513                         break;
 514
 515                 case SO_LINGER:
 516                         lv              = sizeof(v.ling);
 517                         v.ling.l_onoff  = !!sock_flag(sk, SOCK_LINGER);
 518                         v.ling.l_linger = sk->sk_lingertime / HZ;
 519                         break;
 520
 521                 case SO_BSDCOMPAT:
 522                         sock_warn_obsolete_bsdism("getsockopt");
 523                         break;
 524
 525                 case SO_TIMESTAMP:
 526                         v.val = sk->sk_rcvtstamp;
 527                         break;
 528
 529                 case SO_RCVTIMEO:
 530                         lv=sizeof(struct timeval);
 531                         if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
 532                                 v.tm.tv_sec = 0;
 533                                 v.tm.tv_usec = 0;
 534                         } else {
 535                                 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
 536                                 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
 537                         }
 538                         break;
 539
 540                 case SO_SNDTIMEO:
 541                         lv=sizeof(struct timeval);
 542                         if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
 543                                 v.tm.tv_sec = 0;
 544                                 v.tm.tv_usec = 0;
 545                         } else {
 546                                 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
 547                                 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
 548                         }
 549                         break;
 550
 551                 case SO_RCVLOWAT:
 552                         v.val = sk->sk_rcvlowat;
 553                         break;
 554
 555                 case SO_SNDLOWAT:
 556                         v.val=1;
 557                         break;
 558
 559                 case SO_PASSCRED:
 560                         v.val = sock->passcred;
 561                         break;
 562
 563                 case SO_PEERCRED:
 564                         if (len > sizeof(sk->sk_peercred))
 565                                 len = sizeof(sk->sk_peercred);
 566                         if (copy_to_user(optval, &sk->sk_peercred, len))
 567                                 return -EFAULT;
 568                         goto lenout;
 569
 570                 case SO_PEERNAME:
 571                 {
 572                         char address[128];
 573
 574                         if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
 575                                 return -ENOTCONN;
 576                         if (lv < len)
 577                                 return -EINVAL;
 578                         if (copy_to_user(optval, address, len))
 579                                 return -EFAULT;
 580                         goto lenout;
 581                 }
 582
 583                 /* Dubious BSD thing... Probably nobody even uses it, but
 584                  * the UNIX standard wants it for whatever reason... -DaveM
 585                  */
 586                 case SO_ACCEPTCONN:
 587                         v.val = sk->sk_state == TCP_LISTEN;
 588                         break;
 589
 590                 case SO_PEERSEC:
 591                         return security_socket_getpeersec(sock, optval, optlen, len);
 592
 593                 default:
 594                         return(-ENOPROTOOPT);
 595         }
 596         if (len > lv)
 597                 len = lv;
 598         if (copy_to_user(optval, &v, len))
 599                 return -EFAULT;
 600 lenout:
 601         if (put_user(len, optlen))
 602                 return -EFAULT;
 603         return 0;
 604 }
 605
 606 static kmem_cache_t *sk_cachep;
 607
 608 /**
 609  *      sk_alloc - All socket objects are allocated here
 610  *      @family - protocol family
 611  *      @priority - for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
 612  *      @zero_it - zeroes the allocated sock
 613  *      @slab - alternate slab
 614  *
 615  *      All socket objects are allocated here. If @zero_it is non-zero
 616  *      it should have the size of the are to be zeroed, because the
 617  *      private slabcaches have different sizes of the generic struct sock.
 618  *      1 has been kept as a way to say sizeof(struct sock).
 619  */
 620 struct sock *sk_alloc(int family, int priority, int zero_it, kmem_cache_t *slab)
 621 {
 622         struct sock *sk = NULL;
 623
 624         if (!slab)
 625                 slab = sk_cachep;
 626         sk = kmem_cache_alloc(slab, priority);
 627         if (sk) {
 628                 if (zero_it) {
 629                         memset(sk, 0,
 630                                zero_it == 1 ? sizeof(struct sock) : zero_it);
 631                         sk->sk_family = family;
 632                         sock_lock_init(sk);
 633                 }
 634                 sk->sk_slab = slab;
 635
 636                 if (security_sk_alloc(sk, family, priority)) {
 637                         kmem_cache_free(slab, sk);
 638                         sk = NULL;
 639                 }
 640         }
 641         return sk;
 642 }
 643
 644 void sk_free(struct sock *sk)
 645 {
 646         struct sk_filter *filter;
 647         struct module *owner = sk->sk_owner;
 648
 649         if (sk->sk_destruct)
 650                 sk->sk_destruct(sk);
 651
 652         filter = sk->sk_filter;
 653         if (filter) {
 654                 sk_filter_release(sk, filter);
 655                 sk->sk_filter = NULL;
 656         }
 657
 658         sock_disable_timestamp(sk);
 659
 660         if (atomic_read(&sk->sk_omem_alloc))
 661                 printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
 662                        __FUNCTION__, atomic_read(&sk->sk_omem_alloc));
 663
 664         security_sk_free(sk);
 665         kmem_cache_free(sk->sk_slab, sk);
 666         module_put(owner);
 667 }
 668
 669 void __init sk_init(void)
 670 {
 671         sk_cachep = kmem_cache_create("sock", sizeof(struct sock), 0,
 672                                       SLAB_HWCACHE_ALIGN, NULL, NULL);
 673         if (!sk_cachep)
 674                 printk(KERN_CRIT "sk_init: Cannot create sock SLAB cache!");
 675
 676         if (num_physpages <= 4096) {
 677                 sysctl_wmem_max = 32767;
 678                 sysctl_rmem_max = 32767;
 679                 sysctl_wmem_default = 32767;
 680                 sysctl_rmem_default = 32767;
 681         } else if (num_physpages >= 131072) {
 682                 sysctl_wmem_max = 131071;
 683                 sysctl_rmem_max = 131071;
 684         }
 685 }
 686
 687 /*
 688  *      Simple resource managers for sockets.
 689  */
 690
 691
 692 /*
 693  * Write buffer destructor automatically called from kfree_skb.
 694  */
 695 void sock_wfree(struct sk_buff *skb)
 696 {
 697         struct sock *sk = skb->sk;
 698
 699         /* In case it might be waiting for more memory. */
 700         atomic_sub(skb->truesize, &sk->sk_wmem_alloc);
 701         if (!sk->sk_use_write_queue)
 702                 sk->sk_write_space(sk);
 703         sock_put(sk);
 704 }
 705
 706 /*
 707  * Read buffer destructor automatically called from kfree_skb.
 708  */
 709 void sock_rfree(struct sk_buff *skb)
 710 {
 711         struct sock *sk = skb->sk;
 712
 713         atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
 714 }
 715
 716
 717 int sock_i_uid(struct sock *sk)
 718 {
 719         int uid;
 720
 721         read_lock(&sk->sk_callback_lock);
 722         uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
 723         read_unlock(&sk->sk_callback_lock);
 724         return uid;
 725 }
 726
 727 unsigned long sock_i_ino(struct sock *sk)
 728 {
 729         unsigned long ino;
 730
 731         read_lock(&sk->sk_callback_lock);
 732         ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
 733         read_unlock(&sk->sk_callback_lock);
 734         return ino;
 735 }
 736
 737 /*
 738  * Allocate a skb from the socket's send buffer.
 739  */
 740 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, int priority)
 741 {
 742         if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
 743                 struct sk_buff * skb = alloc_skb(size, priority);
 744                 if (skb) {
 745                         skb_set_owner_w(skb, sk);
 746                         return skb;
 747                 }
 748         }
 749         return NULL;
 750 }
 751
 752 /*
 753  * Allocate a skb from the socket's receive buffer.
 754  */
 755 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, int priority)
 756 {
 757         if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
 758                 struct sk_buff *skb = alloc_skb(size, priority);
 759                 if (skb) {
 760                         skb_set_owner_r(skb, sk);
 761                         return skb;
 762                 }
 763         }
 764         return NULL;
 765 }
 766
 767 /*
 768  * Allocate a memory block from the socket's option memory buffer.
 769  */
 770 void *sock_kmalloc(struct sock *sk, int size, int priority)
 771 {
 772         if ((unsigned)size <= sysctl_optmem_max &&
 773             atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
 774                 void *mem;
 775                 /* First do the add, to avoid the race if kmalloc
 776                  * might sleep.
 777                  */
 778                 atomic_add(size, &sk->sk_omem_alloc);
 779                 mem = kmalloc(size, priority);
 780                 if (mem)
 781                         return mem;
 782                 atomic_sub(size, &sk->sk_omem_alloc);
 783         }
 784         return NULL;
 785 }
 786
 787 /*
 788  * Free an option memory block.
 789  */
 790 void sock_kfree_s(struct sock *sk, void *mem, int size)
 791 {
 792         kfree(mem);
 793         atomic_sub(size, &sk->sk_omem_alloc);
 794 }
 795
 796 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
 797    I think, these locks should be removed for datagram sockets.
 798  */
 799 static long sock_wait_for_wmem(struct sock * sk, long timeo)
 800 {
 801         DEFINE_WAIT(wait);
 802
 803         clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 804         for (;;) {
 805                 if (!timeo)
 806                         break;
 807                 if (signal_pending(current))
 808                         break;
 809                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 810                 prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 811                 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
 812                         break;
 813                 if (sk->sk_shutdown & SEND_SHUTDOWN)
 814                         break;
 815                 if (sk->sk_err)
 816                         break;
 817                 timeo = schedule_timeout(timeo);
 818         }
 819         finish_wait(sk->sk_sleep, &wait);
 820         return timeo;
 821 }
 822
 823
 824 /*
 825  *      Generic send/receive buffer handlers
 826  */
 827
 828 static struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
 829                                             unsigned long header_len,
 830                                             unsigned long data_len,
 831                                             int noblock, int *errcode)
 832 {
 833         struct sk_buff *skb;
 834         unsigned int gfp_mask;
 835         long timeo;
 836         int err;
 837
 838         gfp_mask = sk->sk_allocation;
 839         if (gfp_mask & __GFP_WAIT)
 840                 gfp_mask |= __GFP_REPEAT;
 841
 842         timeo = sock_sndtimeo(sk, noblock);
 843         while (1) {
 844                 err = sock_error(sk);
 845                 if (err != 0)
 846                         goto failure;
 847
 848                 err = -EPIPE;
 849                 if (sk->sk_shutdown & SEND_SHUTDOWN)
 850                         goto failure;
 851
 852                 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
 853                         skb = alloc_skb(header_len, sk->sk_allocation);
 854                         if (skb) {
 855                                 int npages;
 856                                 int i;
 857
 858                                 /* No pages, we're done... */
 859                                 if (!data_len)
 860                                         break;
 861
 862                                 npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
 863                                 skb->truesize += data_len;
 864                                 skb_shinfo(skb)->nr_frags = npages;
 865                                 for (i = 0; i < npages; i++) {
 866                                         struct page *page;
 867                                         skb_frag_t *frag;
 868
 869                                         page = alloc_pages(sk->sk_allocation, 0);
 870                                         if (!page) {
 871                                                 err = -ENOBUFS;
 872                                                 skb_shinfo(skb)->nr_frags = i;
 873                                                 kfree_skb(skb);
 874                                                 goto failure;
 875                                         }
 876
 877                                         frag = &skb_shinfo(skb)->frags[i];
 878                                         frag->page = page;
 879                                         frag->page_offset = 0;
 880                                         frag->size = (data_len >= PAGE_SIZE ?
 881                                                       PAGE_SIZE :
 882                                                       data_len);
 883                                         data_len -= PAGE_SIZE;
 884                                 }
 885
 886                                 /* Full success... */
 887                                 break;
 888                         }
 889                         err = -ENOBUFS;
 890                         goto failure;
 891                 }
 892                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
 893                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
 894                 err = -EAGAIN;
 895                 if (!timeo)
 896                         goto failure;
 897                 if (signal_pending(current))
 898                         goto interrupted;
 899                 timeo = sock_wait_for_wmem(sk, timeo);
 900         }
 901
 902         skb_set_owner_w(skb, sk);
 903         return skb;
 904
 905 interrupted:
 906         err = sock_intr_errno(timeo);
 907 failure:
 908         *errcode = err;
 909         return NULL;
 910 }
 911
 912 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
 913                                     int noblock, int *errcode)
 914 {
 915         return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
 916 }
 917
 918 static void __lock_sock(struct sock *sk)
 919 {
 920         DEFINE_WAIT(wait);
 921
 922         for(;;) {
 923                 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
 924                                         TASK_UNINTERRUPTIBLE);
 925                 spin_unlock_bh(&sk->sk_lock.slock);
 926                 schedule();
 927                 spin_lock_bh(&sk->sk_lock.slock);
 928                 if(!sock_owned_by_user(sk))
 929                         break;
 930         }
 931         finish_wait(&sk->sk_lock.wq, &wait);
 932 }
 933
 934 static void __release_sock(struct sock *sk)
 935 {
 936         struct sk_buff *skb = sk->sk_backlog.head;
 937
 938         do {
 939                 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
 940                 bh_unlock_sock(sk);
 941
 942                 do {
 943                         struct sk_buff *next = skb->next;
 944
 945                         skb->next = NULL;
 946                         sk->sk_backlog_rcv(sk, skb);
 947
 948                         /*
 949                          * We are in process context here with softirqs
 950                          * disabled, use cond_resched_softirq() to preempt.
 951                          * This is safe to do because we've taken the backlog
 952                          * queue private:
 953                          */
 954                         cond_resched_softirq();
 955
 956                         skb = next;
 957                 } while (skb != NULL);
 958
 959                 bh_lock_sock(sk);
 960         } while((skb = sk->sk_backlog.head) != NULL);
 961 }
 962
 963 /**
 964  * sk_wait_data - wait for data to arrive at sk_receive_queue
 965  * sk - sock to wait on
 966  * timeo - for how long
 967  *
 968  * Now socket state including sk->sk_err is changed only under lock,
 969  * hence we may omit checks after joining wait queue.
 970  * We check receive queue before schedule() only as optimization;
 971  * it is very likely that release_sock() added new data.
 972  */
 973 int sk_wait_data(struct sock *sk, long *timeo)
 974 {
 975         int rc;
 976         DEFINE_WAIT(wait);
 977
 978         prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
 979         set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 980         rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
 981         clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 982         finish_wait(sk->sk_sleep, &wait);
 983         return rc;
 984 }
 985
 986 EXPORT_SYMBOL(sk_wait_data);
 987
 988 /*
 989  * Set of default routines for initialising struct proto_ops when
 990  * the protocol does not support a particular function. In certain
 991  * cases where it makes no sense for a protocol to have a "do nothing"
 992  * function, some default processing is provided.
 993  */
 994
 995 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
 996 {
 997         return -EOPNOTSUPP;
 998 }
 999
1000 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1001                     int len, int flags)
1002 {
1003         return -EOPNOTSUPP;
1004 }
1005
1006 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1007 {
1008         return -EOPNOTSUPP;
1009 }
1010
1011 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1012 {
1013         return -EOPNOTSUPP;
1014 }
1015
1016 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1017                     int *len, int peer)
1018 {
1019         return -EOPNOTSUPP;
1020 }
1021
1022 unsigned int sock_no_poll(struct file * file, struct socket *sock, poll_table *pt)
1023 {
1024         return 0;
1025 }
1026
1027 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1028 {
1029         return -EOPNOTSUPP;
1030 }
1031
1032 int sock_no_listen(struct socket *sock, int backlog)
1033 {
1034         return -EOPNOTSUPP;
1035 }
1036
1037 int sock_no_shutdown(struct socket *sock, int how)
1038 {
1039         return -EOPNOTSUPP;
1040 }
1041
1042 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1043                     char __user *optval, int optlen)
1044 {
1045         return -EOPNOTSUPP;
1046 }
1047
1048 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1049                     char __user *optval, int __user *optlen)
1050 {
1051         return -EOPNOTSUPP;
1052 }
1053
1054 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1055                     size_t len)
1056 {
1057         return -EOPNOTSUPP;
1058 }
1059
1060 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1061                     size_t len, int flags)
1062 {
1063         return -EOPNOTSUPP;
1064 }
1065
1066 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1067 {
1068         /* Mirror missing mmap method error code */
1069         return -ENODEV;
1070 }
1071
1072 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1073 {
1074         ssize_t res;
1075         struct msghdr msg = {.msg_flags = flags};
1076         struct kvec iov;
1077         char *kaddr = kmap(page);
1078         iov.iov_base = kaddr + offset;
1079         iov.iov_len = size;
1080         res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1081         kunmap(page);
1082         return res;
1083 }
1084
1085 /*
1086  *      Default Socket Callbacks
1087  */
1088
1089 static void sock_def_wakeup(struct sock *sk)
1090 {
1091         read_lock(&sk->sk_callback_lock);
1092         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1093                 wake_up_interruptible_all(sk->sk_sleep);
1094         read_unlock(&sk->sk_callback_lock);
1095 }
1096
1097 static void sock_def_error_report(struct sock *sk)
1098 {
1099         read_lock(&sk->sk_callback_lock);
1100         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1101                 wake_up_interruptible(sk->sk_sleep);
1102         sk_wake_async(sk,0,POLL_ERR);
1103         read_unlock(&sk->sk_callback_lock);
1104 }
1105
1106 static void sock_def_readable(struct sock *sk, int len)
1107 {
1108         read_lock(&sk->sk_callback_lock);
1109         if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1110                 wake_up_interruptible(sk->sk_sleep);
1111         sk_wake_async(sk,1,POLL_IN);
1112         read_unlock(&sk->sk_callback_lock);
1113 }
1114
1115 static void sock_def_write_space(struct sock *sk)
1116 {
1117         read_lock(&sk->sk_callback_lock);
1118
1119         /* Do not wake up a writer until he can make "significant"
1120          * progress.  --DaveM
1121          */
1122         if((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1123                 if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1124                         wake_up_interruptible(sk->sk_sleep);
1125
1126                 /* Should agree with poll, otherwise some programs break */
1127                 if (sock_writeable(sk))
1128                         sk_wake_async(sk, 2, POLL_OUT);
1129         }
1130
1131         read_unlock(&sk->sk_callback_lock);
1132 }
1133
1134 static void sock_def_destruct(struct sock *sk)
1135 {
1136         if (sk->sk_protinfo)
1137                 kfree(sk->sk_protinfo);
1138 }
1139
1140 void sk_send_sigurg(struct sock *sk)
1141 {
1142         if (sk->sk_socket && sk->sk_socket->file)
1143                 if (send_sigurg(&sk->sk_socket->file->f_owner))
1144                         sk_wake_async(sk, 3, POLL_PRI);
1145 }
1146
1147 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1148                     unsigned long expires)
1149 {
1150         if (!mod_timer(timer, expires))
1151                 sock_hold(sk);
1152 }
1153
1154 EXPORT_SYMBOL(sk_reset_timer);
1155
1156 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1157 {
1158         if (timer_pending(timer) && del_timer(timer))
1159                 __sock_put(sk);
1160 }
1161
1162 EXPORT_SYMBOL(sk_stop_timer);
1163
1164 void sock_init_data(struct socket *sock, struct sock *sk)
1165 {
1166         skb_queue_head_init(&sk->sk_receive_queue);
1167         skb_queue_head_init(&sk->sk_write_queue);
1168         skb_queue_head_init(&sk->sk_error_queue);
1169
1170         sk->sk_send_head        =       NULL;
1171
1172         init_timer(&sk->sk_timer);
1173
1174         sk->sk_allocation       =       GFP_KERNEL;
1175         sk->sk_rcvbuf           =       sysctl_rmem_default;
1176         sk->sk_sndbuf           =       sysctl_wmem_default;
1177         sk->sk_state            =       TCP_CLOSE;
1178         sk->sk_zapped           =       1;
1179         sk->sk_socket           =       sock;
1180
1181         if(sock)
1182         {
1183                 sk->sk_type     =       sock->type;
1184                 sk->sk_sleep    =       &sock->wait;
1185                 sock->sk        =       sk;
1186         } else
1187                 sk->sk_sleep    =       NULL;
1188
1189         rwlock_init(&sk->sk_dst_lock);
1190         rwlock_init(&sk->sk_callback_lock);
1191
1192         sk->sk_state_change     =       sock_def_wakeup;
1193         sk->sk_data_ready       =       sock_def_readable;
1194         sk->sk_write_space      =       sock_def_write_space;
1195         sk->sk_error_report     =       sock_def_error_report;
1196         sk->sk_destruct         =       sock_def_destruct;
1197
1198         sk->sk_sndmsg_page      =       NULL;
1199         sk->sk_sndmsg_off       =       0;
1200
1201         sk->sk_peercred.pid     =       0;
1202         sk->sk_peercred.uid     =       -1;
1203         sk->sk_peercred.gid     =       -1;
1204         sk->sk_write_pending    =       0;
1205         sk->sk_rcvlowat         =       1;
1206         sk->sk_rcvtimeo         =       MAX_SCHEDULE_TIMEOUT;
1207         sk->sk_sndtimeo         =       MAX_SCHEDULE_TIMEOUT;
1208         sk->sk_owner            =       NULL;
1209
1210         sk->sk_stamp.tv_sec     = -1L;
1211         sk->sk_stamp.tv_usec    = -1L;
1212
1213         atomic_set(&sk->sk_refcnt, 1);
1214 }
1215
1216 void fastcall lock_sock(struct sock *sk)
1217 {
1218         might_sleep();
1219         spin_lock_bh(&(sk->sk_lock.slock));
1220         if (sk->sk_lock.owner)
1221                 __lock_sock(sk);
1222         sk->sk_lock.owner = (void *)1;
1223         spin_unlock_bh(&(sk->sk_lock.slock));
1224 }
1225
1226 EXPORT_SYMBOL(lock_sock);
1227
1228 void fastcall release_sock(struct sock *sk)
1229 {
1230         spin_lock_bh(&(sk->sk_lock.slock));
1231         if (sk->sk_backlog.tail)
1232                 __release_sock(sk);
1233         sk->sk_lock.owner = NULL;
1234         if (waitqueue_active(&(sk->sk_lock.wq)))
1235                 wake_up(&(sk->sk_lock.wq));
1236         spin_unlock_bh(&(sk->sk_lock.slock));
1237 }
1238 EXPORT_SYMBOL(release_sock);
1239
1240 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
1241 {
1242         if (!sock_flag(sk, SOCK_TIMESTAMP))
1243                 sock_enable_timestamp(sk);
1244         if (sk->sk_stamp.tv_sec == -1)
1245                 return -ENOENT;
1246         if (sk->sk_stamp.tv_sec == 0)
1247                 do_gettimeofday(&sk->sk_stamp);
1248         return copy_to_user(userstamp, &sk->sk_stamp, sizeof(struct timeval)) ?
1249                 -EFAULT : 0;
1250 }
1251 EXPORT_SYMBOL(sock_get_timestamp);
1252
1253 void sock_enable_timestamp(struct sock *sk)
1254 {
1255         if (!sock_flag(sk, SOCK_TIMESTAMP)) {
1256                 sock_set_flag(sk, SOCK_TIMESTAMP);
1257                 net_enable_timestamp();
1258         }
1259 }
1260 EXPORT_SYMBOL(sock_enable_timestamp);
1261
1262 /*
1263  *      Get a socket option on an socket.
1264  *
1265  *      FIX: POSIX 1003.1g is very ambiguous here. It states that
1266  *      asynchronous errors should be reported by getsockopt. We assume
1267  *      this means if you specify SO_ERROR (otherwise whats the point of it).
1268  */
1269 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1270                            char __user *optval, int __user *optlen)
1271 {
1272         struct sock *sk = sock->sk;
1273
1274         return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1275 }
1276
1277 EXPORT_SYMBOL(sock_common_getsockopt);
1278
1279 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1280                         struct msghdr *msg, size_t size, int flags)
1281 {
1282         struct sock *sk = sock->sk;
1283         int addr_len = 0;
1284         int err;
1285
1286         err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
1287                                    flags & ~MSG_DONTWAIT, &addr_len);
1288         if (err >= 0)
1289                 msg->msg_namelen = addr_len;
1290         return err;
1291 }
1292
1293 EXPORT_SYMBOL(sock_common_recvmsg);
1294
1295 /*
1296  *      Set socket options on an inet socket.
1297  */
1298 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1299                            char __user *optval, int optlen)
1300 {
1301         struct sock *sk = sock->sk;
1302
1303         return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1304 }
1305
1306 EXPORT_SYMBOL(sock_common_setsockopt);
1307
1308 void sk_common_release(struct sock *sk)
1309 {
1310         if (sk->sk_prot->destroy)
1311                 sk->sk_prot->destroy(sk);
1312
1313         /*
1314          * Observation: when sock_common_release is called, processes have
1315          * no access to socket. But net still has.
1316          * Step one, detach it from networking:
1317          *
1318          * A. Remove from hash tables.
1319          */
1320
1321         sk->sk_prot->unhash(sk);
1322
1323         /*
1324          * In this point socket cannot receive new packets, but it is possible
1325          * that some packets are in flight because some CPU runs receiver and
1326          * did hash table lookup before we unhashed socket. They will achieve
1327          * receive queue and will be purged by socket destructor.
1328          *
1329          * Also we still have packets pending on receive queue and probably,
1330          * our own packets waiting in device queues. sock_destroy will drain
1331          * receive queue, but transmitted packets will delay socket destruction
1332          * until the last reference will be released.
1333          */
1334
1335         sock_orphan(sk);
1336
1337         xfrm_sk_free_policy(sk);
1338
1339 #ifdef INET_REFCNT_DEBUG
1340         if (atomic_read(&sk->sk_refcnt) != 1)
1341                 printk(KERN_DEBUG "Destruction of the socket %p delayed, c=%d\n",
1342                        sk, atomic_read(&sk->sk_refcnt));
1343 #endif
1344         sock_put(sk);
1345 }
1346
1347 EXPORT_SYMBOL(sk_common_release);
1348
1349 int sk_alloc_slab(struct proto *prot, char *name)
1350 {
1351         prot->slab = kmem_cache_create(name,
1352                                        prot->slab_obj_size, 0,
1353                                        SLAB_HWCACHE_ALIGN, NULL, NULL);
1354
1355         return prot->slab != NULL ? 0 : -ENOBUFS;
1356 }
1357
1358 EXPORT_SYMBOL(sk_alloc_slab);
1359
1360 void sk_free_slab(struct proto *prot)
1361 {
1362         if (prot->slab != NULL) {
1363                 kmem_cache_destroy(prot->slab);
1364                 prot->slab = NULL;
1365         }
1366 }
1367
1368 EXPORT_SYMBOL(sk_free_slab);
1369
1370 EXPORT_SYMBOL(sk_alloc);
1371 EXPORT_SYMBOL(sk_free);
1372 EXPORT_SYMBOL(sk_send_sigurg);
1373 EXPORT_SYMBOL(sock_alloc_send_skb);
1374 EXPORT_SYMBOL(sock_init_data);
1375 EXPORT_SYMBOL(sock_kfree_s);
1376 EXPORT_SYMBOL(sock_kmalloc);
1377 EXPORT_SYMBOL(sock_no_accept);
1378 EXPORT_SYMBOL(sock_no_bind);
1379 EXPORT_SYMBOL(sock_no_connect);
1380 EXPORT_SYMBOL(sock_no_getname);
1381 EXPORT_SYMBOL(sock_no_getsockopt);
1382 EXPORT_SYMBOL(sock_no_ioctl);
1383 EXPORT_SYMBOL(sock_no_listen);
1384 EXPORT_SYMBOL(sock_no_mmap);
1385 EXPORT_SYMBOL(sock_no_poll);
1386 EXPORT_SYMBOL(sock_no_recvmsg);
1387 EXPORT_SYMBOL(sock_no_sendmsg);
1388 EXPORT_SYMBOL(sock_no_sendpage);
1389 EXPORT_SYMBOL(sock_no_setsockopt);
1390 EXPORT_SYMBOL(sock_no_shutdown);
1391 EXPORT_SYMBOL(sock_no_socketpair);
1392 EXPORT_SYMBOL(sock_rfree);
1393 EXPORT_SYMBOL(sock_setsockopt);
1394 EXPORT_SYMBOL(sock_wfree);
1395 EXPORT_SYMBOL(sock_wmalloc);
1396 EXPORT_SYMBOL(sock_i_uid);
1397 EXPORT_SYMBOL(sock_i_ino);
1398 #ifdef CONFIG_SYSCTL
1399 EXPORT_SYMBOL(sysctl_optmem_max);
1400 EXPORT_SYMBOL(sysctl_rmem_max);
1401 EXPORT_SYMBOL(sysctl_wmem_max);
1402 #endif