src/network/tcp.c

   1 /*****************************************************************************
   2  * tcp.c:
   3  *****************************************************************************
   4  * Copyright (C) 2004-2005 VLC authors and VideoLAN
   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 it
  12  * under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this program; if not, write to the Free Software Foundation,
  23  * 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 <unistd.h>
  36
  37 #include <vlc_network.h>
  38 #include <vlc_interrupt.h>
  39
  40 /*****************************************************************************
  41  * SocksNegotiate:
  42  *****************************************************************************
  43  * Negotiate authentication with a SOCKS server.
  44  *****************************************************************************/
  45 static int SocksNegotiate( vlc_object_t *p_obj,
  46                            int fd, int i_socks_version,
  47                            const char *psz_socks_user,
  48                            const char *psz_socks_passwd )
  49 {
  50     uint8_t buffer[128+2*256];
  51     int i_len;
  52     bool b_auth = false;
  53
  54     if( i_socks_version != 5 )
  55         return VLC_SUCCESS;
  56
  57     /* We negotiate authentication */
  58     buffer[0] = i_socks_version;    /* SOCKS version */
  59     if( psz_socks_user != NULL && psz_socks_passwd != NULL )
  60     {
  61         buffer[1] = 2;                  /* Number of methods */
  62         buffer[2] = 0x00;               /* - No auth required */
  63         buffer[3] = 0x02;               /* - USer/Password */
  64         i_len = 4;
  65         b_auth = true;
  66     }
  67     else
  68     {
  69         buffer[1] = 1;                  /* Number of methods */
  70         buffer[2] = 0x00;               /* - No auth required */
  71         i_len = 3;
  72     }
  73
  74     if( net_Write( p_obj, fd, buffer, i_len ) != i_len )
  75         return VLC_EGENERIC;
  76     if( net_Read( p_obj, fd, buffer, 2) != 2 )
  77         return VLC_EGENERIC;
  78
  79     msg_Dbg( p_obj, "socks: v=%d method=%x", buffer[0], buffer[1] );
  80
  81     if( buffer[1] == 0x00 )
  82     {
  83         msg_Dbg( p_obj, "socks: no authentication required" );
  84     }
  85     else if( buffer[1] == 0x02 )
  86     {
  87         if( psz_socks_user == NULL || psz_socks_passwd == NULL )
  88         {
  89             msg_Err( p_obj, "socks: server mandates authentication but "
  90                             "a username and/or password was not supplied" );
  91             return VLC_EGENERIC;
  92         }
  93
  94         int const i_user = strlen( psz_socks_user );
  95         int const i_pasw = strlen( psz_socks_passwd );
  96
  97         if( i_user > 255 || i_pasw > 255 )
  98         {
  99             msg_Err( p_obj, "socks: rejecting username and/or password due to "
 100                             "violation of RFC1929 (longer than 255 bytes)" );
 101             return VLC_EGENERIC;
 102         }
 103
 104         msg_Dbg( p_obj, "socks: username/password authentication" );
 105
 106         buffer[0] = i_socks_version;        /* Version */
 107         buffer[1] = i_user;                 /* User length */
 108         memcpy( &buffer[2], psz_socks_user, i_user );
 109         buffer[2+i_user] = i_pasw;          /* Password length */
 110         memcpy( &buffer[2+i_user+1], psz_socks_passwd, i_pasw );
 111
 112         i_len = 3 + i_user + i_pasw;
 113
 114         if( net_Write( p_obj, fd, buffer, i_len ) != i_len )
 115             return VLC_EGENERIC;
 116
 117         if( net_Read( p_obj, fd, buffer, 2 ) != 2 )
 118             return VLC_EGENERIC;
 119
 120         msg_Dbg( p_obj, "socks: v=%d status=%x", buffer[0], buffer[1] );
 121         if( buffer[1] != 0x00 )
 122         {
 123             msg_Err( p_obj, "socks: authentication rejected" );
 124             return VLC_EGENERIC;
 125         }
 126     }
 127     else
 128     {
 129         if( b_auth )
 130             msg_Err( p_obj, "socks: unsupported authentication method %x",
 131                      buffer[0] );
 132         else
 133             msg_Err( p_obj, "socks: authentication needed" );
 134         return VLC_EGENERIC;
 135     }
 136
 137     return VLC_SUCCESS;
 138 }
 139
 140 /*****************************************************************************
 141  * SocksHandshakeTCP:
 142  *****************************************************************************
 143  * Open a TCP connection using a SOCKS server and return a handle (RFC 1928)
 144  *****************************************************************************/
 145 static int SocksHandshakeTCP( vlc_object_t *p_obj,
 146                               int fd,
 147                               int i_socks_version,
 148                               const char *psz_user, const char *psz_passwd,
 149                               const char *psz_host, int i_port )
 150 {
 151     uint8_t buffer[128+2*256];
 152
 153     if( i_socks_version != 4 && i_socks_version != 5 )
 154     {
 155         msg_Warn( p_obj, "invalid socks protocol version %d", i_socks_version );
 156         i_socks_version = 5;
 157     }
 158
 159     if( i_socks_version == 5 &&
 160         SocksNegotiate( p_obj, fd, i_socks_version,
 161                         psz_user, psz_passwd ) )
 162         return VLC_EGENERIC;
 163
 164     if( i_socks_version == 4 )
 165     {
 166         /* v4 only support ipv4 */
 167         static const struct addrinfo hints = {
 168             .ai_family = AF_INET,
 169             .ai_socktype = SOCK_STREAM,
 170             .ai_protocol = IPPROTO_TCP,
 171             .ai_flags = AI_IDN,
 172         };
 173         struct addrinfo *res;
 174
 175         if (vlc_getaddrinfo_i11e(psz_host, 0, &hints, &res))
 176             return VLC_EGENERIC;
 177
 178         buffer[0] = i_socks_version;
 179         buffer[1] = 0x01;               /* CONNECT */
 180         SetWBE( &buffer[2], i_port );   /* Port */
 181         memcpy (&buffer[4],             /* Address */
 182                 &((struct sockaddr_in *)(res->ai_addr))->sin_addr, 4);
 183         freeaddrinfo (res);
 184
 185         buffer[8] = 0;                  /* Empty user id */
 186
 187         if( net_Write( p_obj, fd, buffer, 9 ) != 9 )
 188             return VLC_EGENERIC;
 189         if( net_Read( p_obj, fd, buffer, 8 ) != 8 )
 190             return VLC_EGENERIC;
 191
 192         msg_Dbg( p_obj, "socks: v=%d cd=%d",
 193                  buffer[0], buffer[1] );
 194
 195         if( buffer[1] != 90 )
 196             return VLC_EGENERIC;
 197     }
 198     else if( i_socks_version == 5 )
 199     {
 200         int i_hlen = __MIN(strlen( psz_host ), 255);
 201         int i_len;
 202
 203         buffer[0] = i_socks_version;    /* Version */
 204         buffer[1] = 0x01;               /* Cmd: connect */
 205         buffer[2] = 0x00;               /* Reserved */
 206         buffer[3] = 3;                  /* ATYP: for now domainname */
 207
 208         buffer[4] = i_hlen;
 209         memcpy( &buffer[5], psz_host, i_hlen );
 210         SetWBE( &buffer[5+i_hlen], i_port );
 211
 212         i_len = 5 + i_hlen + 2;
 213
 214
 215         if( net_Write( p_obj, fd, buffer, i_len ) != i_len )
 216             return VLC_EGENERIC;
 217
 218         /* Read the header */
 219         if( net_Read( p_obj, fd, buffer, 5 ) != 5 )
 220             return VLC_EGENERIC;
 221
 222         msg_Dbg( p_obj, "socks: v=%d rep=%d atyp=%d",
 223                  buffer[0], buffer[1], buffer[3] );
 224
 225         if( buffer[1] != 0x00 )
 226         {
 227             msg_Err( p_obj, "socks: CONNECT request failed" );
 228             return VLC_EGENERIC;
 229         }
 230
 231         /* Read the remaining bytes */
 232         if( buffer[3] == 0x01 )
 233             i_len = 4-1 + 2;
 234         else if( buffer[3] == 0x03 )
 235             i_len = buffer[4] + 2;
 236         else if( buffer[3] == 0x04 )
 237             i_len = 16-1+2;
 238         else
 239             return VLC_EGENERIC;
 240
 241         if( net_Read( p_obj, fd, buffer, i_len ) != i_len )
 242             return VLC_EGENERIC;
 243     }
 244
 245     return VLC_SUCCESS;
 246 }
 247
 248 int (net_ConnectTCP)(vlc_object_t *obj, const char *host, int serv)
 249 {
 250     const char *realhost;
 251     int realserv;
 252
 253     char *socks = var_InheritString(obj, "socks");
 254     if (socks != NULL)
 255     {
 256         realhost = socks;
 257
 258         char *p = strchr(socks, ':');
 259         if (p != NULL)
 260         {
 261             *(p++) = '\0';
 262             realserv = atoi(p);
 263         }
 264         else
 265             realserv = 1080;
 266
 267         msg_Dbg(obj, "net: connecting to %s port %d (SOCKS) "
 268                 "for %s port %d", realhost, realserv, host, serv);
 269     }
 270     else
 271     {
 272         msg_Dbg(obj, "net: connecting to %s port %d", host, serv);
 273         realhost = host;
 274         realserv = serv;
 275     }
 276
 277     int fd = net_Connect(obj, realhost, realserv, SOCK_STREAM, IPPROTO_TCP);
 278
 279     if (socks != NULL && fd != -1)
 280     {
 281         /* NOTE: psz_socks already free'd! */
 282         char *user = var_InheritString(obj, "socks-user");
 283         char *pwd = var_InheritString(obj, "socks-pwd");
 284
 285         if (SocksHandshakeTCP(obj, fd, 5, user, pwd, host, serv))
 286         {
 287             msg_Err(obj, "SOCKS handshake failed");
 288             net_Close(fd);
 289             fd = -1;
 290         }
 291
 292         free(pwd);
 293         free(user);
 294     }
 295
 296     return fd;
 297 }