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
  29 #include <vlc/vlc.h>
  30 #include <vlc_interface.h>
  31 #include <vlc_input.h>
  32
  33 #include <stdbool.h>
  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 #ifdef HAVE_POLL
  47 #   include <poll.h>
  48 #endif
  49
  50 #include <vlc_network.h>
  51 #include <vlc_url.h>
  52 #include <vlc_vlm.h>
  53
  54 #define READ_MODE_PWD 1
  55 #define READ_MODE_CMD 2
  56 #define WRITE_MODE_PWD 3 // when we write the word "Password:"
  57 #define WRITE_MODE_CMD 4
  58
  59 /* telnet commands */
  60 #define TEL_WILL    251
  61 #define TEL_WONT    252
  62 #define TEL_DO      253
  63 #define TEL_DONT    254
  64 #define TEL_IAC     255
  65 #define TEL_ECHO    1
  66
  67 /*****************************************************************************
  68  * Module descriptor
  69  *****************************************************************************/
  70 static int  Open ( vlc_object_t * );
  71 static void Close( vlc_object_t * );
  72
  73 #define TELNETHOST_TEXT N_( "Host" )
  74 #define TELNETHOST_LONGTEXT N_( "This is the host on which the " \
  75     "interface will listen. It defaults to all network interfaces (0.0.0.0)." \
  76     " If you want this interface to be available only on the local " \
  77     "machine, enter \"127.0.0.1\"." )
  78 #define TELNETPORT_TEXT N_( "Port" )
  79 #define TELNETPORT_LONGTEXT N_( "This is the TCP port on which this " \
  80     "interface will listen. It defaults to 4212." )
  81 #define TELNETPORT_DEFAULT 4212
  82 #define TELNETPWD_TEXT N_( "Password" )
  83 #define TELNETPWD_LONGTEXT N_( "A single administration password is used " \
  84     "to protect this interface. The default value is \"admin\"." )
  85 #define TELNETPWD_DEFAULT "admin"
  86
  87 vlc_module_begin();
  88     set_shortname( "Telnet" );
  89     set_category( CAT_INTERFACE );
  90     set_subcategory( SUBCAT_INTERFACE_CONTROL );
  91     add_string( "telnet-host", "", NULL, TELNETHOST_TEXT,
  92                  TELNETHOST_LONGTEXT, VLC_TRUE );
  93     add_integer( "telnet-port", TELNETPORT_DEFAULT, NULL, TELNETPORT_TEXT,
  94                  TELNETPORT_LONGTEXT, VLC_TRUE );
  95     add_password( "telnet-password", TELNETPWD_DEFAULT, NULL, TELNETPWD_TEXT,
  96                 TELNETPWD_LONGTEXT, VLC_TRUE );
  97     set_description( _("VLM remote control interface") );
  98     add_category_hint( "VLM", NULL, VLC_FALSE );
  99     set_capability( "interface", 0 );
 100     set_callbacks( Open , Close );
 101 vlc_module_end();
 102
 103 /*****************************************************************************
 104  * Local prototypes.
 105  *****************************************************************************/
 106 static void Run( intf_thread_t * );
 107
 108 typedef struct
 109 {
 110     int        i_mode; /* read or write */
 111     int        fd;
 112     char       buffer_read[1000]; // 1000 byte per command should be sufficient
 113     char      *buffer_write;
 114     char      *p_buffer_read;
 115     char      *p_buffer_write; // the position in the buffer
 116     int        i_buffer_write; // the number of byte we still have to send
 117     int        i_tel_cmd; // for specific telnet commands
 118
 119 } telnet_client_t;
 120
 121 static char *MessageToString( vlm_message_t *, int );
 122 static void Write_message( telnet_client_t *, vlm_message_t *, const char *, int );
 123
 124 struct intf_sys_t
 125 {
 126    telnet_client_t **clients;
 127    int             i_clients;
 128    int             *pi_fd;
 129    vlm_t           *mediatheque;
 130 };
 131
 132 /*
 133  * getPort: Decide which port to use. There are two possibilities to
 134  * specify a port: integrated in the --telnet-host option with :PORT
 135  * or using the --telnet-port option. The --telnet-port option has
 136  * precedence.
 137  * This code relies upon the fact the url.i_port is 0 if the :PORT
 138  * option is missing from --telnet-host.
 139  */
 140 static int getPort(intf_thread_t *p_intf, vlc_url_t url, int i_port)
 141 {
 142     // Print error if two different ports have been specified
 143     if (url.i_port != 0  &&
 144         i_port != TELNETPORT_DEFAULT &&
 145         url.i_port != i_port )
 146     {
 147         msg_Err( p_intf, "ignoring port %d and using %d", url.i_port,
 148                  i_port);
 149     }
 150     if (i_port != TELNETPORT_DEFAULT)
 151     {
 152         return i_port;
 153     }
 154     if (url.i_port != 0)
 155     {
 156          return url.i_port;
 157     }
 158     return i_port;
 159 }
 160
 161 /*****************************************************************************
 162  * Open: initialize dummy interface
 163  *****************************************************************************/
 164 static int Open( vlc_object_t *p_this )
 165 {
 166     intf_thread_t *p_intf = (intf_thread_t*) p_this;
 167     vlm_t *mediatheque;
 168     char *psz_address;
 169     vlc_url_t url;
 170     int i_telnetport;
 171
 172     if( !(mediatheque = vlm_New( p_intf )) )
 173     {
 174         msg_Err( p_intf, "cannot start VLM" );
 175         return VLC_EGENERIC;
 176     }
 177
 178     msg_Info( p_intf, "using the VLM interface plugin..." );
 179
 180     i_telnetport = config_GetInt( p_intf, "telnet-port" );
 181     psz_address  = config_GetPsz( p_intf, "telnet-host" );
 182
 183     vlc_UrlParse(&url, psz_address, 0);
 184
 185     // There might be two ports given, resolve any potentially
 186     // conflict
 187     url.i_port = getPort(p_intf, url, i_telnetport);
 188
 189     p_intf->p_sys = malloc( sizeof( intf_sys_t ) );
 190     if( ( p_intf->p_sys->pi_fd = net_ListenTCP( p_intf, url.psz_host, url.i_port ) )
 191                 == NULL )
 192     {
 193         msg_Err( p_intf, "cannot listen for telnet" );
 194         vlc_UrlClean(&url);
 195         free( psz_address );
 196         free( p_intf->p_sys );
 197         return VLC_EGENERIC;
 198     }
 199     msg_Info( p_intf,
 200               "telnet interface started on interface %s %d",
 201               url.psz_host, url.i_port );
 202
 203     p_intf->p_sys->i_clients   = 0;
 204     p_intf->p_sys->clients     = NULL;
 205     p_intf->p_sys->mediatheque = mediatheque;
 206     p_intf->pf_run = Run;
 207
 208     vlc_UrlClean(&url);
 209     free( psz_address );
 210     return VLC_SUCCESS;
 211 }
 212
 213 /*****************************************************************************
 214  * Close:
 215  *****************************************************************************/
 216 static void Close( vlc_object_t *p_this )
 217 {
 218     intf_thread_t *p_intf = (intf_thread_t*)p_this;
 219     intf_sys_t    *p_sys  = p_intf->p_sys;
 220     int i;
 221
 222     for( i = 0; i < p_sys->i_clients; i++ )
 223     {
 224         telnet_client_t *cl = p_sys->clients[i];
 225         net_Close( cl->fd );
 226         free( cl );
 227         p_sys->clients[i] = NULL;
 228     }
 229     if( p_sys->clients != NULL ) free( p_sys->clients );
 230
 231     net_ListenClose( p_sys->pi_fd );
 232
 233     vlm_Delete( p_sys->mediatheque );
 234
 235     free( p_sys );
 236 }
 237
 238 /*****************************************************************************
 239  * Run: main loop
 240  *****************************************************************************/
 241 static void Run( intf_thread_t *p_intf )
 242 {
 243     intf_sys_t     *p_sys = p_intf->p_sys;
 244     char           *psz_password;
 245     unsigned        nlisten = 0;
 246
 247     for (const int *pfd = p_sys->pi_fd; *pfd != -1; pfd++)
 248         nlisten++; /* How many listening sockets do we have? */
 249
 250     psz_password = config_GetPsz( p_intf, "telnet-password" );
 251
 252     while( !intf_ShouldDie( p_intf ) )
 253     {
 254         unsigned ncli = p_sys->i_clients;
 255         struct pollfd ufd[ncli + nlisten];
 256
 257         for (unsigned i = 0; i < ncli; i++)
 258         {
 259             telnet_client_t *cl = p_sys->clients[i];
 260
 261             ufd[i].fd = cl->fd;
 262             if( (cl->i_mode == WRITE_MODE_PWD) || (cl->i_mode == WRITE_MODE_CMD) )
 263                 ufd[i].events = POLLOUT;
 264             else
 265                 ufd[i].events = POLLIN;
 266             ufd[i].revents = 0;
 267         }
 268
 269         for (unsigned i = 0; i < nlisten; i++)
 270         {
 271             ufd[ncli + i].fd = p_sys->pi_fd[i];
 272             ufd[ncli + i].events = POLLIN;
 273             ufd[ncli + i].revents = 0;
 274         }
 275
 276         /* FIXME: arbitrary tick */
 277         switch (poll (ufd, sizeof (ufd) / sizeof (ufd[0]), 500))
 278         {
 279             case -1:
 280                 if (net_errno != EINTR)
 281                 {
 282                     msg_Err (p_intf, "network poll error");
 283                     msleep (1000);
 284                     continue;
 285                 }
 286             case 0:
 287                 continue;
 288         }
 289
 290         /* check if there is something to do with the socket */
 291         for (unsigned i = 0; i < ncli; i++)
 292         {
 293             telnet_client_t *cl = p_sys->clients[i];
 294
 295             if (ufd[i].revents & (POLLERR|POLLHUP))
 296             {
 297             drop:
 298                 net_Close( cl->fd );
 299                 TAB_REMOVE( p_intf->p_sys->i_clients ,
 300                             p_intf->p_sys->clients , cl );
 301                 free( cl );
 302                 continue;
 303             }
 304
 305             if (ufd[i].revents & POLLOUT && (cl->i_buffer_write > 0))
 306             {
 307                 ssize_t i_len;
 308
 309                 i_len = send( cl->fd, cl->p_buffer_write ,
 310                               cl->i_buffer_write, 0 );
 311                 if( i_len > 0 )
 312                 {
 313                     cl->p_buffer_write += i_len;
 314                     cl->i_buffer_write -= i_len;
 315                 }
 316             }
 317             if (ufd[i].revents & POLLIN)
 318             {
 319                 bool end = false;
 320                 ssize_t i_recv;
 321
 322                 while( ((i_recv=recv( cl->fd, cl->p_buffer_read, 1, 0 )) > 0) &&
 323                        ((cl->p_buffer_read - cl->buffer_read) < 999) )
 324                 {
 325                     switch( cl->i_tel_cmd )
 326                     {
 327                     case 0:
 328                         switch( *(uint8_t *)cl->p_buffer_read )
 329                         {
 330                         case '\r':
 331                             break;
 332                         case '\n':
 333                             *cl->p_buffer_read = '\n';
 334                             end = true;
 335                             break;
 336                         case TEL_IAC: // telnet specific command
 337                             cl->i_tel_cmd = 1;
 338                             cl->p_buffer_read++;
 339                             break;
 340                         default:
 341                             cl->p_buffer_read++;
 342                             break;
 343                         }
 344                         break;
 345                     case 1:
 346                         switch( *(uint8_t *)cl->p_buffer_read )
 347                         {
 348                         case TEL_WILL: case TEL_WONT:
 349                         case TEL_DO: case TEL_DONT:
 350                             cl->i_tel_cmd++;
 351                             cl->p_buffer_read++;
 352                             break;
 353                         default:
 354                             cl->i_tel_cmd = 0;
 355                             cl->p_buffer_read--;
 356                             break;
 357                         }
 358                         break;
 359                     case 2:
 360                         cl->i_tel_cmd = 0;
 361                         cl->p_buffer_read -= 2;
 362                         break;
 363                     }
 364
 365                     if( end ) break;
 366                 }
 367
 368                 if( (cl->p_buffer_read - cl->buffer_read) == 999 )
 369                 {
 370                     Write_message( cl, NULL, "Line too long\r\n",
 371                                    cl->i_mode + 2 );
 372                 }
 373
 374                 if (i_recv <= 0)
 375                     goto drop;
 376             }
 377         }
 378
 379         /* and now we should bidouille the data we received / send */
 380         for(int i = 0 ; i < p_sys->i_clients ; i++ )
 381         {
 382             telnet_client_t *cl = p_sys->clients[i];
 383
 384             if( cl->i_mode >= WRITE_MODE_PWD && cl->i_buffer_write == 0 )
 385             {
 386                // we have finished to send
 387                cl->i_mode -= 2; // corresponding READ MODE
 388             }
 389             else if( cl->i_mode == READ_MODE_PWD &&
 390                      *cl->p_buffer_read == '\n' )
 391             {
 392                 *cl->p_buffer_read = '\0';
 393                 if( !psz_password || !strcmp( psz_password, cl->buffer_read ) )
 394                 {
 395                     Write_message( cl, NULL, "\xff\xfc\x01\r\nWelcome, "
 396                                    "Master\r\n> ", WRITE_MODE_CMD );
 397                 }
 398                 else
 399                 {
 400                     /* wrong password */
 401                     Write_message( cl, NULL,
 402                                    "\r\nWrong password.\r\nPassword: ",
 403                                    WRITE_MODE_PWD );
 404                 }
 405             }
 406             else if( cl->i_mode == READ_MODE_CMD &&
 407                      *cl->p_buffer_read == '\n' )
 408             {
 409                 /* ok, here is a command line */
 410                 if( !strncmp( cl->buffer_read, "logout", 6 ) ||
 411                     !strncmp( cl->buffer_read, "quit", 4 )  ||
 412                     !strncmp( cl->buffer_read, "exit", 4 ) )
 413                 {
 414                     net_Close( cl->fd );
 415                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 416                                 p_intf->p_sys->clients , cl );
 417                     free( cl );
 418                 }
 419                 else if( !strncmp( cl->buffer_read, "shutdown", 8 ) )
 420                 {
 421                     msg_Err( p_intf, "shutdown requested" );
 422                     vlc_object_kill( p_intf->p_libvlc );
 423                 }
 424                 else if( *cl->buffer_read == '@'
 425                           && strchr( cl->buffer_read, ' ' ) )
 426                 {
 427                     /* Module specific commands (use same syntax as in the
 428                      * rc interface) */
 429                     char *psz_name = cl->buffer_read + 1;
 430                     char *psz_cmd, *psz_arg, *psz_msg;
 431                     int i_ret;
 432
 433                     psz_cmd = strchr( cl->buffer_read, ' ' );
 434                     *psz_cmd = '\0';  psz_cmd++;
 435                     if( ( psz_arg = strchr( psz_cmd, '\n' ) ) ) *psz_arg = '\0';
 436                     if( ( psz_arg = strchr( psz_cmd, '\r' ) ) ) *psz_arg = '\0';
 437                     if( ( psz_arg = strchr( psz_cmd, ' ' ) )
 438                         && *psz_arg )
 439                     {
 440                         *psz_arg = '\0';
 441                         psz_arg++;
 442                     }
 443
 444                     i_ret = var_Command( p_intf, psz_name, psz_cmd, psz_arg,
 445                                          &psz_msg );
 446
 447                     if( psz_msg )
 448                     {
 449                         vlm_message_t *message;
 450                         message = vlm_MessageNew( "Module command", psz_msg );
 451                         Write_message( cl, message, NULL, WRITE_MODE_CMD );
 452                         vlm_MessageDelete( message );
 453                         free( psz_msg );
 454                     }
 455                 }
 456                 else
 457                 {
 458                     vlm_message_t *message;
 459
 460                     /* create a standard string */
 461                     *cl->p_buffer_read = '\0';
 462
 463                     vlm_ExecuteCommand( p_sys->mediatheque, cl->buffer_read,
 464                                         &message );
 465                     if( !strncmp( cl->buffer_read, "help", 4 ) )
 466                     {
 467                         vlm_message_t *p_my_help =
 468                             vlm_MessageNew( "Telnet Specific Commands:", NULL );
 469                         vlm_MessageAdd( p_my_help,
 470                             vlm_MessageNew( "logout, quit, exit" , NULL ) );
 471                         vlm_MessageAdd( p_my_help,
 472                             vlm_MessageNew( "shutdown" , NULL ) );
 473                         vlm_MessageAdd( p_my_help,
 474                             vlm_MessageNew( "@moduleinstance command argument",
 475                                              NULL) );
 476                         vlm_MessageAdd( message, p_my_help );
 477                     }
 478                     Write_message( cl, message, NULL, WRITE_MODE_CMD );
 479                     vlm_MessageDelete( message );
 480
 481                 }
 482             }
 483         }
 484
 485         /* handle new connections */
 486         for (unsigned i = 0; i < nlisten; i++)
 487         {
 488             int fd;
 489
 490             if (ufd[ncli + i].revents == 0)
 491                 continue;
 492
 493             fd = net_AcceptSingle (VLC_OBJECT(p_intf), ufd[ncli + i].fd);
 494             if (fd == -1)
 495                 continue;
 496
 497             telnet_client_t *cl = malloc( sizeof( telnet_client_t ));
 498             if (cl == NULL)
 499             {
 500                 net_Close (fd);
 501                 continue;
 502             }
 503
 504             memset( cl, 0, sizeof(telnet_client_t) );
 505             cl->i_tel_cmd = 0;
 506             cl->fd = fd;
 507             cl->buffer_write = NULL;
 508             cl->p_buffer_write = cl->buffer_write;
 509             Write_message( cl, NULL,
 510                            "Password: \xff\xfb\x01" , WRITE_MODE_PWD );
 511             TAB_APPEND( p_sys->i_clients, p_sys->clients, cl );
 512         }
 513     }
 514     if( psz_password )
 515         free( psz_password );
 516 }
 517
 518 static void Write_message( telnet_client_t *client, vlm_message_t *message,
 519                            const char *string_message, int i_mode )
 520 {
 521     char *psz_message;
 522
 523     client->p_buffer_read = client->buffer_read;
 524     (client->p_buffer_read)[0] = 0; // if (cl->p_buffer_read)[0] = '\n'
 525     if( client->buffer_write ) free( client->buffer_write );
 526
 527     /* generate the psz_message string */
 528     if( message )
 529     {
 530         /* ok, look for vlm_message_t */
 531         psz_message = MessageToString( message, 0 );
 532     }
 533     else
 534     {
 535         /* it is a basic string_message */
 536         psz_message = strdup( string_message );
 537     }
 538
 539     client->buffer_write = client->p_buffer_write = psz_message;
 540     client->i_buffer_write = strlen( psz_message );
 541     client->i_mode = i_mode;
 542 }
 543
 544 /* We need the level of the message to put a beautiful indentation.
 545  * first level is 0 */
 546 static char *MessageToString( vlm_message_t *message, int i_level )
 547 {
 548 #define STRING_CR "\r\n"
 549 #define STRING_TAIL "> "
 550
 551     char *psz_message;
 552     int i, i_message = sizeof( STRING_TAIL );
 553
 554     if( !message || !message->psz_name )
 555     {
 556         return strdup( STRING_CR STRING_TAIL );
 557     }
 558     else if( !i_level && !message->i_child && !message->psz_value  )
 559     {
 560         /* A command is successful. Don't write anything */
 561         return strdup( /*STRING_CR*/ STRING_TAIL );
 562     }
 563
 564     i_message += strlen( message->psz_name ) + i_level * sizeof( "    " ) + 1;
 565     psz_message = malloc( i_message );
 566     *psz_message = 0;
 567     for( i = 0; i < i_level; i++ ) strcat( psz_message, "    " );
 568     strcat( psz_message, message->psz_name );
 569
 570     if( message->psz_value )
 571     {
 572         i_message += sizeof( " : " ) + strlen( message->psz_value ) +
 573             sizeof( STRING_CR );
 574         psz_message = realloc( psz_message, i_message );
 575         strcat( psz_message, " : " );
 576         strcat( psz_message, message->psz_value );
 577         strcat( psz_message, STRING_CR );
 578     }
 579     else
 580     {
 581         i_message += sizeof( STRING_CR );
 582         psz_message = realloc( psz_message, i_message );
 583         strcat( psz_message, STRING_CR );
 584     }
 585
 586     for( i = 0; i < message->i_child; i++ )
 587     {
 588         char *child_message =
 589             MessageToString( message->child[i], i_level + 1 );
 590
 591         i_message += strlen( child_message );
 592         psz_message = realloc( psz_message, i_message );
 593         strcat( psz_message, child_message );
 594         free( child_message );
 595     }
 596
 597     if( i_level == 0 ) strcat( psz_message, STRING_TAIL );
 598
 599     return psz_message;
 600 }