src/network/tcp.c

   1 /*****************************************************************************
   2  * tcp.c:
   3  *****************************************************************************
   4  * Copyright (C) 2004-2005 the VideoLAN team
   5  * Copyright (C) 2005-2006 Rémi Denis-Courmont
   6  * $Id$
   7  *
   8  * Authors: Laurent Aimar <fenrir@videolan.org>
   9  *          Rémi Denis-Courmont <rem # videolan.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Preamble
  28  *****************************************************************************/
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc_common.h>
  34
  35 #include <errno.h>
  36 #include <assert.h>
  37
  38 #ifdef HAVE_FCNTL_H
  39 #   include <fcntl.h>
  40 #endif
  41 #ifdef HAVE_SYS_TIME_H
  42 #    include <sys/time.h>
  43 #endif
  44 #ifdef HAVE_UNISTD_H
  45 #   include <unistd.h>
  46 #endif
  47 #ifdef HAVE_POLL
  48 # include <poll.h>
  49 #endif
  50
  51 #include <vlc_network.h>
  52 #if defined (WIN32) || defined (UNDER_CE)
  53 #   undef EINPROGRESS
  54 #   define EINPROGRESS WSAEWOULDBLOCK
  55 #   undef EINTR
  56 #   define EINTR WSAEINTR
  57 #   undef ETIMEDOUT
  58 #   define ETIMEDOUT WSAETIMEDOUT
  59 #endif
  60
  61 static int SocksNegotiate( vlc_object_t *, int fd, int i_socks_version,
  62                            const char *psz_user, const char *psz_passwd );
  63 static int SocksHandshakeTCP( vlc_object_t *,
  64                               int fd, int i_socks_version,
  65                               const char *psz_user, const char *psz_passwd,
  66                               const char *psz_host, int i_port );
  67 extern int net_Socket( vlc_object_t *p_this, int i_family, int i_socktype,
  68                        int i_protocol );
  69
  70 /*****************************************************************************
  71  * __net_Connect:
  72  *****************************************************************************
  73  * Open a network connection.
  74  * @return socket handler or -1 on error.
  75  *****************************************************************************/
  76 int __net_Connect( vlc_object_t *p_this, const char *psz_host, int i_port,
  77                    int type, int proto )
  78 {
  79     struct addrinfo hints, *res, *ptr;
  80     const char      *psz_realhost;
  81     char            *psz_socks;
  82     int             i_realport, i_val, i_handle = -1;
  83
  84     int evfd = vlc_object_waitpipe (p_this);
  85     if (evfd == -1)
  86         return -1;
  87
  88     memset( &hints, 0, sizeof( hints ) );
  89     hints.ai_socktype = SOCK_STREAM;
  90
  91     psz_socks = var_CreateGetNonEmptyString( p_this, "socks" );
  92     if( psz_socks != NULL )
  93     {
  94         char *psz = strchr( psz_socks, ':' );
  95
  96         if( psz )
  97             *psz++ = '\0';
  98
  99         psz_realhost = psz_socks;
 100         i_realport = ( psz != NULL ) ? atoi( psz ) : 1080;
 101         hints.ai_flags &= ~AI_NUMERICHOST;
 102
 103         msg_Dbg( p_this, "net: connecting to %s port %d (SOCKS) "
 104                  "for %s port %d", psz_realhost, i_realport,
 105                  psz_host, i_port );
 106
 107         /* We only implement TCP with SOCKS */
 108         switch( type )
 109         {
 110             case 0:
 111                 type = SOCK_STREAM;
 112             case SOCK_STREAM:
 113                 break;
 114             default:
 115                 msg_Err( p_this, "Socket type not supported through SOCKS" );
 116                 free( psz_socks );
 117                 return -1;
 118         }
 119         switch( proto )
 120         {
 121             case 0:
 122                 proto = IPPROTO_TCP;
 123             case IPPROTO_TCP:
 124                 break;
 125             default:
 126                 msg_Err( p_this, "Transport not supported through SOCKS" );
 127                 free( psz_socks );
 128                 return -1;
 129         }
 130     }
 131     else
 132     {
 133         psz_realhost = psz_host;
 134         i_realport = i_port;
 135
 136         msg_Dbg( p_this, "net: connecting to %s port %d", psz_realhost,
 137                  i_realport );
 138     }
 139
 140     i_val = vlc_getaddrinfo( p_this, psz_realhost, i_realport, &hints, &res );
 141     free( psz_socks );
 142
 143     if( i_val )
 144     {
 145         msg_Err( p_this, "cannot resolve %s port %d : %s", psz_realhost,
 146                  i_realport, vlc_gai_strerror( i_val ) );
 147         return -1;
 148     }
 149
 150     for( ptr = res; ptr != NULL; ptr = ptr->ai_next )
 151     {
 152         int fd = net_Socket( p_this, ptr->ai_family, type ?: ptr->ai_socktype,
 153                              proto ?: ptr->ai_protocol );
 154         if( fd == -1 )
 155         {
 156             msg_Dbg( p_this, "socket error: %m" );
 157             continue;
 158         }
 159
 160         if( connect( fd, ptr->ai_addr, ptr->ai_addrlen ) )
 161         {
 162             int timeout, val;
 163
 164             if( net_errno != EINPROGRESS && net_errno != EINTR )
 165             {
 166                 msg_Err( p_this, "connection failed: %m" );
 167                 goto next_ai;
 168             }
 169             msg_Dbg( p_this, "connection: %m" );
 170
 171             timeout = var_CreateGetInteger (p_this, "ipv4-timeout");
 172             if (timeout < 0)
 173             {
 174                 msg_Err( p_this, "invalid negative value for ipv4-timeout" );
 175                 timeout = 0;
 176             }
 177
 178             struct pollfd ufd[2] = {
 179                 { .fd = fd,   .events = POLLOUT },
 180                 { .fd = evfd, .events = POLLIN },
 181             };
 182
 183             do
 184                 /* NOTE: timeout screwed up if we catch a signal (EINTR) */
 185                 val = poll (ufd, sizeof (ufd) / sizeof (ufd[0]), timeout);
 186             while ((val == -1) && (net_errno == EINTR));
 187
 188             switch (val)
 189             {
 190                  case -1: /* error */
 191                      msg_Err (p_this, "connection polling error: %m");
 192                      goto next_ai;
 193
 194                  case 0: /* timeout */
 195                      msg_Warn (p_this, "connection timed out");
 196                      goto next_ai;
 197
 198                  default: /* something happended */
 199                      if (ufd[1].revents)
 200                          goto next_ai; /* LibVLC object killed */
 201             }
 202
 203             /* There is NO WAY around checking SO_ERROR.
 204              * Don't ifdef it out!!! */
 205             if (getsockopt (fd, SOL_SOCKET, SO_ERROR, &val,
 206                             &(socklen_t){ sizeof (val) }) || val)
 207             {
 208                 errno = val;
 209                 msg_Err (p_this, "connection failed: %m");
 210                 goto next_ai;
 211             }
 212         }
 213
 214         msg_Dbg( p_this, "connection succeeded (socket = %d)", fd );
 215         i_handle = fd; /* success! */
 216         break;
 217
 218 next_ai: /* failure */
 219         net_Close( fd );
 220         continue;
 221     }
 222
 223     vlc_freeaddrinfo( res );
 224
 225     if( i_handle == -1 )
 226         return -1;
 227
 228     if( psz_socks != NULL )
 229     {
 230         /* NOTE: psz_socks already free'd! */
 231         char *psz_user = var_CreateGetNonEmptyString( p_this, "socks-user" );
 232         char *psz_pwd  = var_CreateGetNonEmptyString( p_this, "socks-pwd" );
 233
 234         if( SocksHandshakeTCP( p_this, i_handle, 5, psz_user, psz_pwd,
 235                                psz_host, i_port ) )
 236         {
 237             msg_Err( p_this, "SOCKS handshake failed" );
 238             net_Close( i_handle );
 239             i_handle = -1;
 240         }
 241
 242         free( psz_user );
 243         free( psz_pwd );
 244     }
 245
 246     return i_handle;
 247 }
 248
 249
 250 int net_AcceptSingle (vlc_object_t *obj, int lfd)
 251 {
 252     int fd;
 253     do
 254         fd = accept (lfd, NULL, NULL);
 255     while (fd == -1 && errno == EINTR);
 256
 257     if (fd == -1)
 258     {
 259         if (net_errno != EAGAIN)
 260             msg_Err (obj, "accept failed (from socket %d): %m", lfd);
 261         return -1;
 262     }
 263
 264     msg_Dbg (obj, "accepted socket %d (from socket %d)", fd, lfd);
 265     net_SetupSocket (fd);
 266     return fd;
 267 }
 268
 269
 270 /*****************************************************************************
 271  * __net_Accept:
 272  *****************************************************************************
 273  * Accept a connection on a set of listening sockets and return it
 274  *****************************************************************************/
 275 int __net_Accept( vlc_object_t *p_this, int *pi_fd, mtime_t i_wait )
 276 {
 277     int timeout = (i_wait < 0) ? -1 : i_wait / 1000;
 278     int evfd = vlc_object_waitpipe (p_this);
 279
 280     if (evfd == -1)
 281         return -1;
 282
 283     assert( pi_fd != NULL );
 284
 285     for (;;)
 286     {
 287         unsigned n = 0;
 288         while (pi_fd[n] != -1)
 289             n++;
 290         struct pollfd ufd[n + 1];
 291
 292         /* Initialize file descriptor set */
 293         for (unsigned i = 0; i <= n; i++)
 294         {
 295             ufd[i].fd = (i < n) ? pi_fd[i] : evfd;
 296             ufd[i].events = POLLIN;
 297             ufd[i].revents = 0;
 298         }
 299         if (evfd == -1)
 300             n--; /* avoid EBADF */
 301
 302         switch (poll (ufd, n, timeout))
 303         {
 304             case -1:
 305                 if (net_errno == EINTR)
 306                     continue;
 307                 msg_Err (p_this, "poll error: %m");
 308                 return -1;
 309             case 0:
 310                 errno = ETIMEDOUT;
 311                 return -1;
 312         }
 313
 314         if (ufd[n].revents)
 315         {
 316             errno = EINTR;
 317             break;
 318         }
 319
 320         for (unsigned i = 0; i < n; i++)
 321         {
 322             if (ufd[i].revents == 0)
 323                 continue;
 324
 325             int sfd = ufd[i].fd;
 326             int fd = net_AcceptSingle (p_this, sfd);
 327             if (fd == -1)
 328                 continue;
 329
 330             /*
 331              * Move listening socket to the end to let the others in the
 332              * set a chance next time.
 333              */
 334             memmove (pi_fd + i, pi_fd + i + 1, n - (i + 1));
 335             pi_fd[n - 1] = sfd;
 336             return fd;
 337         }
 338     }
 339     return -1;
 340 }
 341
 342
 343 /*****************************************************************************
 344  * SocksNegotiate:
 345  *****************************************************************************
 346  * Negotiate authentication with a SOCKS server.
 347  *****************************************************************************/
 348 static int SocksNegotiate( vlc_object_t *p_obj,
 349                            int fd, int i_socks_version,
 350                            const char *psz_socks_user,
 351                            const char *psz_socks_passwd )
 352 {
 353     uint8_t buffer[128+2*256];
 354     int i_len;
 355     bool b_auth = false;
 356
 357     if( i_socks_version != 5 )
 358         return VLC_SUCCESS;
 359
 360     /* We negotiate authentication */
 361
 362     if( ( psz_socks_user == NULL ) && ( psz_socks_passwd == NULL ) )
 363         b_auth = true;
 364
 365     buffer[0] = i_socks_version;    /* SOCKS version */
 366     if( b_auth )
 367     {
 368         buffer[1] = 2;                  /* Number of methods */
 369         buffer[2] = 0x00;               /* - No auth required */
 370         buffer[3] = 0x02;               /* - USer/Password */
 371         i_len = 4;
 372     }
 373     else
 374     {
 375         buffer[1] = 1;                  /* Number of methods */
 376         buffer[2] = 0x00;               /* - No auth required */
 377         i_len = 3;
 378     }
 379
 380     if( net_Write( p_obj, fd, NULL, buffer, i_len ) != i_len )
 381         return VLC_EGENERIC;
 382     if( net_Read( p_obj, fd, NULL, buffer, 2, true ) != 2 )
 383         return VLC_EGENERIC;
 384
 385     msg_Dbg( p_obj, "socks: v=%d method=%x", buffer[0], buffer[1] );
 386
 387     if( buffer[1] == 0x00 )
 388     {
 389         msg_Dbg( p_obj, "socks: no authentication required" );
 390     }
 391     else if( buffer[1] == 0x02 )
 392     {
 393         int i_len1 = __MIN( strlen(psz_socks_user), 255 );
 394         int i_len2 = __MIN( strlen(psz_socks_passwd), 255 );
 395         msg_Dbg( p_obj, "socks: username/password authentication" );
 396
 397         /* XXX: we don't support user/pwd > 255 (truncated)*/
 398         buffer[0] = i_socks_version;        /* Version */
 399         buffer[1] = i_len1;                 /* User length */
 400         memcpy( &buffer[2], psz_socks_user, i_len1 );
 401         buffer[2+i_len1] = i_len2;          /* Password length */
 402         memcpy( &buffer[2+i_len1+1], psz_socks_passwd, i_len2 );
 403
 404         i_len = 3 + i_len1 + i_len2;
 405
 406         if( net_Write( p_obj, fd, NULL, buffer, i_len ) != i_len )
 407             return VLC_EGENERIC;
 408
 409         if( net_Read( p_obj, fd, NULL, buffer, 2, true ) != 2 )
 410             return VLC_EGENERIC;
 411
 412         msg_Dbg( p_obj, "socks: v=%d status=%x", buffer[0], buffer[1] );
 413         if( buffer[1] != 0x00 )
 414         {
 415             msg_Err( p_obj, "socks: authentication rejected" );
 416             return VLC_EGENERIC;
 417         }
 418     }
 419     else
 420     {
 421         if( b_auth )
 422             msg_Err( p_obj, "socks: unsupported authentication method %x",
 423                      buffer[0] );
 424         else
 425             msg_Err( p_obj, "socks: authentification needed" );
 426         return VLC_EGENERIC;
 427     }
 428
 429     return VLC_SUCCESS;
 430 }
 431
 432 /*****************************************************************************
 433  * SocksHandshakeTCP:
 434  *****************************************************************************
 435  * Open a TCP connection using a SOCKS server and return a handle (RFC 1928)
 436  *****************************************************************************/
 437 static int SocksHandshakeTCP( vlc_object_t *p_obj,
 438                               int fd,
 439                               int i_socks_version,
 440                               const char *psz_user, const char *psz_passwd,
 441                               const char *psz_host, int i_port )
 442 {
 443     uint8_t buffer[128+2*256];
 444
 445     if( i_socks_version != 4 && i_socks_version != 5 )
 446     {
 447         msg_Warn( p_obj, "invalid socks protocol version %d", i_socks_version );
 448         i_socks_version = 5;
 449     }
 450
 451     if( i_socks_version == 5 &&
 452         SocksNegotiate( p_obj, fd, i_socks_version,
 453                         psz_user, psz_passwd ) )
 454         return VLC_EGENERIC;
 455
 456     if( i_socks_version == 4 )
 457     {
 458         struct addrinfo hints, *p_res;
 459
 460         /* v4 only support ipv4 */
 461         memset (&hints, 0, sizeof (hints));
 462         hints.ai_family = AF_INET;
 463         if( vlc_getaddrinfo( p_obj, psz_host, 0, &hints, &p_res ) )
 464             return VLC_EGENERIC;
 465
 466         buffer[0] = i_socks_version;
 467         buffer[1] = 0x01;               /* CONNECT */
 468         SetWBE( &buffer[2], i_port );   /* Port */
 469         memcpy( &buffer[4],             /* Address */
 470                 &((struct sockaddr_in *)(p_res->ai_addr))->sin_addr, 4 );
 471         vlc_freeaddrinfo( p_res );
 472
 473         buffer[8] = 0;                  /* Empty user id */
 474
 475         if( net_Write( p_obj, fd, NULL, buffer, 9 ) != 9 )
 476             return VLC_EGENERIC;
 477         if( net_Read( p_obj, fd, NULL, buffer, 8, true ) != 8 )
 478             return VLC_EGENERIC;
 479
 480         msg_Dbg( p_obj, "socks: v=%d cd=%d",
 481                  buffer[0], buffer[1] );
 482
 483         if( buffer[1] != 90 )
 484             return VLC_EGENERIC;
 485     }
 486     else if( i_socks_version == 5 )
 487     {
 488         int i_hlen = __MIN(strlen( psz_host ), 255);
 489         int i_len;
 490
 491         buffer[0] = i_socks_version;    /* Version */
 492         buffer[1] = 0x01;               /* Cmd: connect */
 493         buffer[2] = 0x00;               /* Reserved */
 494         buffer[3] = 3;                  /* ATYP: for now domainname */
 495
 496         buffer[4] = i_hlen;
 497         memcpy( &buffer[5], psz_host, i_hlen );
 498         SetWBE( &buffer[5+i_hlen], i_port );
 499
 500         i_len = 5 + i_hlen + 2;
 501
 502
 503         if( net_Write( p_obj, fd, NULL, buffer, i_len ) != i_len )
 504             return VLC_EGENERIC;
 505
 506         /* Read the header */
 507         if( net_Read( p_obj, fd, NULL, buffer, 5, true ) != 5 )
 508             return VLC_EGENERIC;
 509
 510         msg_Dbg( p_obj, "socks: v=%d rep=%d atyp=%d",
 511                  buffer[0], buffer[1], buffer[3] );
 512
 513         if( buffer[1] != 0x00 )
 514         {
 515             msg_Err( p_obj, "socks: CONNECT request failed\n" );
 516             return VLC_EGENERIC;
 517         }
 518
 519         /* Read the remaining bytes */
 520         if( buffer[3] == 0x01 )
 521             i_len = 4-1 + 2;
 522         else if( buffer[3] == 0x03 )
 523             i_len = buffer[4] + 2;
 524         else if( buffer[3] == 0x04 )
 525             i_len = 16-1+2;
 526         else
 527             return VLC_EGENERIC;
 528
 529         if( net_Read( p_obj, fd, NULL, buffer, i_len, true ) != i_len )
 530             return VLC_EGENERIC;
 531     }
 532
 533     return VLC_SUCCESS;
 534 }
 535
 536 void net_ListenClose( int *pi_fd )
 537 {
 538     if( pi_fd != NULL )
 539     {
 540         int *pi;
 541
 542         for( pi = pi_fd; *pi != -1; pi++ )
 543             net_Close( *pi );
 544         free( pi_fd );
 545     }
 546 }