git.sesse.net Git - vlc/blob - modules/control/telnet.c

   1 /*****************************************************************************
   2  * telnet.c: VLM interface plugin
   3  *****************************************************************************
   4  * Copyright (C) 2000-2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Simon Latapie <garf@videolan.org>
   8  *          Laurent Aimar <fenrir@videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <stdlib.h>                                      /* malloc(), free() */
  29
  30 #include <vlc/vlc.h>
  31 #include <vlc_interface.h>
  32 #include <vlc_input.h>
  33
  34 #include <sys/stat.h>
  35
  36 #include <errno.h>
  37 #include <fcntl.h>
  38
  39 #ifdef HAVE_SYS_TIME_H
  40 #    include <sys/time.h>
  41 #endif
  42
  43 #ifdef HAVE_UNISTD_H
  44 #   include <unistd.h>
  45 #endif
  46
  47 #include <vlc_network.h>
  48 #include <vlc_url.h>
  49 #include <vlc_vlm.h>
  50
  51 #define READ_MODE_PWD 1
  52 #define READ_MODE_CMD 2
  53 #define WRITE_MODE_PWD 3 // when we write the word "Password:"
  54 #define WRITE_MODE_CMD 4
  55
  56 /* telnet commands */
  57 #define TEL_WILL    251
  58 #define TEL_WONT    252
  59 #define TEL_DO      253
  60 #define TEL_DONT    254
  61 #define TEL_IAC     255
  62 #define TEL_ECHO    1
  63
  64 /*****************************************************************************
  65  * Module descriptor
  66  *****************************************************************************/
  67 static int  Open ( vlc_object_t * );
  68 static void Close( vlc_object_t * );
  69
  70 #define TELNETHOST_TEXT N_( "Host" )
  71 #define TELNETHOST_LONGTEXT N_( "This is the host on which the " \
  72     "interface will listen. It defaults to all network interfaces (0.0.0.0)." \
  73     " If you want this interface to be available only on the local " \
  74     "machine, enter \"127.0.0.1\"." )
  75 #define TELNETPORT_TEXT N_( "Port" )
  76 #define TELNETPORT_LONGTEXT N_( "This is the TCP port on which this " \
  77     "interface will listen. It defaults to 4212." )
  78 #define TELNETPORT_DEFAULT 4212
  79 #define TELNETPWD_TEXT N_( "Password" )
  80 #define TELNETPWD_LONGTEXT N_( "A single administration password is used " \
  81     "to protect this interface. The default value is \"admin\"." )
  82 #define TELNETPWD_DEFAULT "admin"
  83
  84 vlc_module_begin();
  85     set_shortname( "Telnet" );
  86     set_category( CAT_INTERFACE );
  87     set_subcategory( SUBCAT_INTERFACE_CONTROL );
  88     add_string( "telnet-host", "", NULL, TELNETHOST_TEXT,
  89                  TELNETHOST_LONGTEXT, VLC_TRUE );
  90     add_integer( "telnet-port", TELNETPORT_DEFAULT, NULL, TELNETPORT_TEXT,
  91                  TELNETPORT_LONGTEXT, VLC_TRUE );
  92     add_string( "telnet-password", TELNETPWD_DEFAULT, NULL, TELNETPWD_TEXT,
  93                 TELNETPWD_LONGTEXT, VLC_TRUE );
  94     set_description( _("VLM remote control interface") );
  95     add_category_hint( "VLM", NULL, VLC_FALSE );
  96     set_capability( "interface", 0 );
  97     set_callbacks( Open , Close );
  98 vlc_module_end();
  99
 100 /*****************************************************************************
 101  * Local prototypes.
 102  *****************************************************************************/
 103 static void Run( intf_thread_t * );
 104
 105 typedef struct
 106 {
 107     int        i_mode; /* read or write */
 108     int        fd;
 109     char       buffer_read[1000]; // 1000 byte per command should be sufficient
 110     char      *buffer_write;
 111     char      *p_buffer_read;
 112     char      *p_buffer_write; // the position in the buffer
 113     int        i_buffer_write; // the number of byte we still have to send
 114     int        i_tel_cmd; // for specific telnet commands
 115
 116 } telnet_client_t;
 117
 118 static char *MessageToString( vlm_message_t *, int );
 119 static void Write_message( telnet_client_t *, vlm_message_t *, char *, int );
 120
 121 struct intf_sys_t
 122 {
 123    telnet_client_t **clients;
 124    int             i_clients;
 125    int             *pi_fd;
 126    vlm_t           *mediatheque;
 127 };
 128
 129 /*
 130  * getPort: Decide which port to use. There are two possibilities to
 131  * specify a port: integrated in the --telnet-host option with :PORT
 132  * or using the --telnet-port option. The --telnet-port option has
 133  * precedence.
 134  * This code relies upon the fact the url.i_port is 0 if the :PORT
 135  * option is missing from --telnet-host.
 136  */
 137 static int getPort(intf_thread_t *p_intf, vlc_url_t url, int i_port)
 138 {
 139     // Print error if two different ports have been specified
 140     if (url.i_port != 0  &&
 141         i_port != TELNETPORT_DEFAULT &&
 142         url.i_port != i_port )
 143     {
 144         msg_Err( p_intf, "ignoring port %d and using %d", url.i_port,
 145                  i_port);
 146     }
 147     if (i_port != TELNETPORT_DEFAULT)
 148     {
 149         return i_port;
 150     }
 151     if (url.i_port != 0)
 152     {
 153          return url.i_port;
 154     }
 155     return i_port;
 156 }
 157
 158 /*****************************************************************************
 159  * Open: initialize dummy interface
 160  *****************************************************************************/
 161 static int Open( vlc_object_t *p_this )
 162 {
 163     intf_thread_t *p_intf = (intf_thread_t*) p_this;
 164     vlm_t *mediatheque;
 165     char *psz_address;
 166     vlc_url_t url;
 167     int i_telnetport;
 168
 169     if( !(mediatheque = vlm_New( p_intf )) )
 170     {
 171         msg_Err( p_intf, "cannot start VLM" );
 172         return VLC_EGENERIC;
 173     }
 174
 175     msg_Info( p_intf, "using the VLM interface plugin..." );
 176
 177     i_telnetport = config_GetInt( p_intf, "telnet-port" );
 178     psz_address  = config_GetPsz( p_intf, "telnet-host" );
 179
 180     vlc_UrlParse(&url, psz_address, 0);
 181
 182     // There might be two ports given, resolve any potentially
 183     // conflict
 184     url.i_port = getPort(p_intf, url, i_telnetport);
 185
 186     p_intf->p_sys = malloc( sizeof( intf_sys_t ) );
 187     if( ( p_intf->p_sys->pi_fd = net_ListenTCP( p_intf, url.psz_host, url.i_port ) )
 188                 == NULL )
 189     {
 190         msg_Err( p_intf, "cannot listen for telnet" );
 191         vlc_UrlClean(&url);
 192         free( psz_address );
 193         free( p_intf->p_sys );
 194         return VLC_EGENERIC;
 195     }
 196     msg_Info( p_intf,
 197               "telnet interface started on interface %s %d",
 198               url.psz_host, url.i_port );
 199
 200     p_intf->p_sys->i_clients   = 0;
 201     p_intf->p_sys->clients     = NULL;
 202     p_intf->p_sys->mediatheque = mediatheque;
 203     p_intf->pf_run = Run;
 204
 205     vlc_UrlClean(&url);
 206     free( psz_address );
 207     return VLC_SUCCESS;
 208 }
 209
 210 /*****************************************************************************
 211  * Close:
 212  *****************************************************************************/
 213 static void Close( vlc_object_t *p_this )
 214 {
 215     intf_thread_t *p_intf = (intf_thread_t*)p_this;
 216     intf_sys_t    *p_sys  = p_intf->p_sys;
 217     int i;
 218
 219     for( i = 0; i < p_sys->i_clients; i++ )
 220     {
 221         telnet_client_t *cl = p_sys->clients[i];
 222
 223         net_Close( cl->fd );
 224         free( cl );
 225     }
 226     if( p_sys->clients != NULL ) free( p_sys->clients );
 227
 228     net_ListenClose( p_sys->pi_fd );
 229
 230     vlm_Delete( p_sys->mediatheque );
 231
 232     free( p_sys );
 233 }
 234
 235 /*****************************************************************************
 236  * Run: main loop
 237  *****************************************************************************/
 238 static void Run( intf_thread_t *p_intf )
 239 {
 240     intf_sys_t     *p_sys = p_intf->p_sys;
 241     struct timeval  timeout;
 242     char           *psz_password;
 243
 244     psz_password = config_GetPsz( p_intf, "telnet-password" );
 245
 246     while( !intf_ShouldDie( p_intf ) )
 247     {
 248         fd_set fds_read, fds_write;
 249         int    i_handle_max = 0;
 250         int    i_ret, i_len, fd, i;
 251
 252         /* if a new client wants to communicate */
 253         fd = net_Accept( p_intf, p_sys->pi_fd, p_sys->i_clients > 0 ? 0 : -1 );
 254         if( fd > 0 )
 255         {
 256             telnet_client_t *cl;
 257
 258             /* to be non blocking */
 259 #if defined( WIN32 ) || defined( UNDER_CE )
 260             {
 261                 unsigned long i_dummy = 1;
 262                 ioctlsocket( fd, FIONBIO, &i_dummy );
 263             }
 264 #else
 265             fcntl( fd, F_SETFL, O_NONBLOCK );
 266 #endif
 267             cl = malloc( sizeof( telnet_client_t ));
 268             cl->i_tel_cmd = 0;
 269             cl->fd = fd;
 270             cl->buffer_write = NULL;
 271             cl->p_buffer_write = cl->buffer_write;
 272             Write_message( cl, NULL,
 273                            _( "Password: \xff\xfb\x01" ), WRITE_MODE_PWD );
 274
 275             TAB_APPEND( p_sys->i_clients, p_sys->clients, cl );
 276         }
 277
 278         /* to do a proper select */
 279         FD_ZERO( &fds_read );
 280         FD_ZERO( &fds_write );
 281
 282         for( i = 0 ; i < p_sys->i_clients ; i++ )
 283         {
 284             telnet_client_t *cl = p_sys->clients[i];
 285
 286             if( cl->i_mode == WRITE_MODE_PWD || cl->i_mode == WRITE_MODE_CMD )
 287             {
 288                 FD_SET( cl->fd , &fds_write );
 289             }
 290             else
 291             {
 292                 FD_SET( cl->fd , &fds_read );
 293             }
 294             i_handle_max = __MAX( i_handle_max, cl->fd );
 295         }
 296
 297         timeout.tv_sec = 0;
 298         timeout.tv_usec = 500*1000;
 299
 300         i_ret = select( i_handle_max + 1, &fds_read, &fds_write, 0, &timeout );
 301         if( i_ret == -1 && errno != EINTR )
 302         {
 303             msg_Warn( p_intf, "cannot select sockets" );
 304             msleep( 1000 );
 305             continue;
 306         }
 307         else if( i_ret <= 0 )
 308         {
 309             continue;
 310         }
 311
 312         /* check if there is something to do with the socket */
 313         for( i = 0 ; i < p_sys->i_clients ; i++ )
 314         {
 315             telnet_client_t *cl = p_sys->clients[i];
 316
 317             if( FD_ISSET(cl->fd , &fds_write) && cl->i_buffer_write > 0 )
 318             {
 319                 i_len = send( cl->fd , cl->p_buffer_write ,
 320                               cl->i_buffer_write , 0 );
 321                 if( i_len > 0 )
 322                 {
 323                     cl->p_buffer_write += i_len;
 324                     cl->i_buffer_write -= i_len;
 325                 }
 326             }
 327             else if( FD_ISSET( cl->fd, &fds_read) )
 328             {
 329                 int i_end = 0;
 330                 int i_recv;
 331
 332                 while( (i_recv=recv( cl->fd, cl->p_buffer_read, 1, 0 )) > 0 &&
 333                        cl->p_buffer_read - cl->buffer_read < 999 )
 334                 {
 335                     switch( cl->i_tel_cmd )
 336                     {
 337                     case 0:
 338                         switch( *(uint8_t *)cl->p_buffer_read )
 339                         {
 340                         case '\r':
 341                             break;
 342                         case '\n':
 343                             *cl->p_buffer_read = '\n';
 344                             i_end = 1;
 345                             break;
 346                         case TEL_IAC: // telnet specific command
 347                             cl->i_tel_cmd = 1;
 348                             cl->p_buffer_read++;
 349                             break;
 350                         default:
 351                             cl->p_buffer_read++;
 352                             break;
 353                         }
 354                         break;
 355                     case 1:
 356                         switch( *(uint8_t *)cl->p_buffer_read )
 357                         {
 358                         case TEL_WILL: case TEL_WONT:
 359                         case TEL_DO: case TEL_DONT:
 360                             cl->i_tel_cmd++;
 361                             cl->p_buffer_read++;
 362                             break;
 363                         default:
 364                             cl->i_tel_cmd = 0;
 365                             cl->p_buffer_read--;
 366                             break;
 367                         }
 368                         break;
 369                     case 2:
 370                         cl->i_tel_cmd = 0;
 371                         cl->p_buffer_read -= 2;
 372                         break;
 373                     }
 374
 375                     if( i_end != 0 ) break;
 376                 }
 377
 378                 if( cl->p_buffer_read - cl->buffer_read == 999 )
 379                 {
 380                     Write_message( cl, NULL, _( "Line too long\r\n" ),
 381                                    cl->i_mode + 2 );
 382                 }
 383
 384                 if (i_recv == 0)
 385                 {
 386                     net_Close( cl->fd );
 387                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 388                                 p_intf->p_sys->clients , cl );
 389                     free( cl );
 390                 }
 391             }
 392         }
 393
 394         /* and now we should bidouille the data we received / send */
 395         for( i = 0 ; i < p_sys->i_clients ; i++ )
 396         {
 397             telnet_client_t *cl = p_sys->clients[i];
 398
 399             if( cl->i_mode >= WRITE_MODE_PWD && cl->i_buffer_write == 0 )
 400             {
 401                // we have finished to send
 402                cl->i_mode -= 2; // corresponding READ MODE
 403             }
 404             else if( cl->i_mode == READ_MODE_PWD &&
 405                      *cl->p_buffer_read == '\n' )
 406             {
 407                 *cl->p_buffer_read = '\0';
 408                 if( strcmp( psz_password, cl->buffer_read ) == 0 )
 409                 {
 410                     Write_message( cl, NULL, _( "\xff\xfc\x01\r\nWelcome, "
 411                                    "Master\r\n> " ), WRITE_MODE_CMD );
 412                 }
 413                 else
 414                 {
 415                     /* wrong password */
 416                     Write_message( cl, NULL,
 417                                    _( "\r\nWrong password.\r\nPassword: " ),
 418                                    WRITE_MODE_PWD );
 419                 }
 420             }
 421             else if( cl->i_mode == READ_MODE_CMD &&
 422                      *cl->p_buffer_read == '\n' )
 423             {
 424                 /* ok, here is a command line */
 425                 if( !strncmp( cl->buffer_read, "logout", 6 ) ||
 426                     !strncmp( cl->buffer_read, "quit", 4 )  ||
 427                     !strncmp( cl->buffer_read, "exit", 4 ) )
 428                 {
 429                     net_Close( cl->fd );
 430                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 431                                 p_intf->p_sys->clients , cl );
 432                     free( cl );
 433                 }
 434                 else if( !strncmp( cl->buffer_read, "shutdown", 8 ) )
 435                 {
 436                     msg_Err( p_intf, "shutdown requested" );
 437                     p_intf->p_libvlc->b_die = VLC_TRUE;
 438                 }
 439                 else
 440                 {
 441                     vlm_message_t *message;
 442
 443                     /* create a standard string */
 444                     *cl->p_buffer_read = '\0';
 445
 446                     vlm_ExecuteCommand( p_sys->mediatheque, cl->buffer_read,
 447                                         &message );
 448                     if( !strncmp( cl->buffer_read, "help", 4 ) )
 449                     {
 450                         vlm_message_t *p_my_help =
 451                             vlm_MessageNew( "Telnet Specific Commands:", NULL );
 452                         vlm_MessageAdd( p_my_help,
 453                             vlm_MessageNew( "logout, quit, exit" , NULL ) );
 454                         vlm_MessageAdd( p_my_help,
 455                             vlm_MessageNew( "shutdown" , NULL ) );
 456                         vlm_MessageAdd( message, p_my_help );
 457                     }
 458                     Write_message( cl, message, NULL, WRITE_MODE_CMD );
 459                     vlm_MessageDelete( message );
 460
 461                 }
 462             }
 463         }
 464     }
 465 }
 466
 467 static void Write_message( telnet_client_t *client, vlm_message_t *message,
 468                            char *string_message, int i_mode )
 469 {
 470     char *psz_message;
 471
 472     client->p_buffer_read = client->buffer_read;
 473     (client->p_buffer_read)[0] = 0; // if (cl->p_buffer_read)[0] = '\n'
 474     if( client->buffer_write ) free( client->buffer_write );
 475
 476     /* generate the psz_message string */
 477     if( message )
 478     {
 479         /* ok, look for vlm_message_t */
 480         psz_message = MessageToString( message, 0 );
 481     }
 482     else
 483     {
 484         /* it is a basic string_message */
 485         psz_message = strdup( string_message );
 486     }
 487
 488     client->buffer_write = client->p_buffer_write = psz_message;
 489     client->i_buffer_write = strlen( psz_message );
 490     client->i_mode = i_mode;
 491 }
 492
 493 /* We need the level of the message to put a beautiful indentation.
 494  * first level is 0 */
 495 static char *MessageToString( vlm_message_t *message, int i_level )
 496 {
 497 #define STRING_CR "\r\n"
 498 #define STRING_TAIL "> "
 499
 500     char *psz_message;
 501     int i, i_message = sizeof( STRING_TAIL );
 502
 503     if( !message || !message->psz_name )
 504     {
 505         return strdup( STRING_CR STRING_TAIL );
 506     }
 507     else if( !i_level && !message->i_child && !message->psz_value  )
 508     {
 509         /* A command is successful. Don't write anything */
 510         return strdup( /*STRING_CR*/ STRING_TAIL );
 511     }
 512
 513     i_message += strlen( message->psz_name ) + i_level * sizeof( "    " ) + 1;
 514     psz_message = malloc( i_message );
 515     *psz_message = 0;
 516     for( i = 0; i < i_level; i++ ) strcat( psz_message, "    " );
 517     strcat( psz_message, message->psz_name );
 518
 519     if( message->psz_value )
 520     {
 521         i_message += sizeof( " : " ) + strlen( message->psz_value ) +
 522             sizeof( STRING_CR );
 523         psz_message = realloc( psz_message, i_message );
 524         strcat( psz_message, " : " );
 525         strcat( psz_message, message->psz_value );
 526         strcat( psz_message, STRING_CR );
 527     }
 528     else
 529     {
 530         i_message += sizeof( STRING_CR );
 531         psz_message = realloc( psz_message, i_message );
 532         strcat( psz_message, STRING_CR );
 533     }
 534
 535     for( i = 0; i < message->i_child; i++ )
 536     {
 537         char *child_message =
 538             MessageToString( message->child[i], i_level + 1 );
 539
 540         i_message += strlen( child_message );
 541         psz_message = realloc( psz_message, i_message );
 542         strcat( psz_message, child_message );
 543         free( child_message );
 544     }
 545
 546     if( i_level == 0 ) strcat( psz_message, STRING_TAIL );
 547
 548     return psz_message;
 549 }