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 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc/vlc.h>
  34 #include <vlc_plugin.h>
  35 #include <vlc_interface.h>
  36 #include <vlc_input.h>
  37
  38 #include <stdbool.h>
  39 #include <sys/stat.h>
  40
  41 #include <errno.h>
  42 #include <fcntl.h>
  43
  44 #ifdef HAVE_SYS_TIME_H
  45 #    include <sys/time.h>
  46 #endif
  47
  48 #ifdef HAVE_UNISTD_H
  49 #   include <unistd.h>
  50 #endif
  51 #ifdef HAVE_POLL
  52 #   include <poll.h>
  53 #endif
  54
  55 #include <vlc_network.h>
  56 #include <vlc_url.h>
  57 #include <vlc_vlm.h>
  58
  59 #define READ_MODE_PWD 1
  60 #define READ_MODE_CMD 2
  61 #define WRITE_MODE_PWD 3 // when we write the word "Password:"
  62 #define WRITE_MODE_CMD 4
  63
  64 /* telnet commands */
  65 #define TEL_WILL    251
  66 #define TEL_WONT    252
  67 #define TEL_DO      253
  68 #define TEL_DONT    254
  69 #define TEL_IAC     255
  70 #define TEL_ECHO    1
  71
  72 /*****************************************************************************
  73  * Module descriptor
  74  *****************************************************************************/
  75 static int  Open ( vlc_object_t * );
  76 static void Close( vlc_object_t * );
  77
  78 #define TELNETHOST_TEXT N_( "Host" )
  79 #define TELNETHOST_LONGTEXT N_( "This is the host on which the " \
  80     "interface will listen. It defaults to all network interfaces (0.0.0.0)." \
  81     " If you want this interface to be available only on the local " \
  82     "machine, enter \"127.0.0.1\"." )
  83 #define TELNETPORT_TEXT N_( "Port" )
  84 #define TELNETPORT_LONGTEXT N_( "This is the TCP port on which this " \
  85     "interface will listen. It defaults to 4212." )
  86 #define TELNETPORT_DEFAULT 4212
  87 #define TELNETPWD_TEXT N_( "Password" )
  88 #define TELNETPWD_LONGTEXT N_( "A single administration password is used " \
  89     "to protect this interface. The default value is \"admin\"." )
  90 #define TELNETPWD_DEFAULT "admin"
  91
  92 vlc_module_begin();
  93     set_shortname( "Telnet" );
  94     set_category( CAT_INTERFACE );
  95     set_subcategory( SUBCAT_INTERFACE_CONTROL );
  96     add_string( "telnet-host", "", NULL, TELNETHOST_TEXT,
  97                  TELNETHOST_LONGTEXT, true );
  98     add_integer( "telnet-port", TELNETPORT_DEFAULT, NULL, TELNETPORT_TEXT,
  99                  TELNETPORT_LONGTEXT, true );
 100     add_password( "telnet-password", TELNETPWD_DEFAULT, NULL, TELNETPWD_TEXT,
 101                 TELNETPWD_LONGTEXT, true );
 102     set_description( N_("VLM remote control interface") );
 103     add_category_hint( "VLM", NULL, false );
 104     set_capability( "interface", 0 );
 105     set_callbacks( Open , Close );
 106 vlc_module_end();
 107
 108 /*****************************************************************************
 109  * Local prototypes.
 110  *****************************************************************************/
 111 static void Run( intf_thread_t * );
 112
 113 typedef struct
 114 {
 115     int        i_mode; /* read or write */
 116     int        fd;
 117     char       buffer_read[1000]; // 1000 byte per command should be sufficient
 118     char      *buffer_write;
 119     char      *p_buffer_read;
 120     char      *p_buffer_write; // the position in the buffer
 121     int        i_buffer_write; // the number of byte we still have to send
 122     int        i_tel_cmd; // for specific telnet commands
 123
 124 } telnet_client_t;
 125
 126 static char *MessageToString( vlm_message_t *, int );
 127 static void Write_message( telnet_client_t *, vlm_message_t *, const char *, int );
 128
 129 struct intf_sys_t
 130 {
 131    telnet_client_t **clients;
 132    int             i_clients;
 133    int             *pi_fd;
 134    vlm_t           *mediatheque;
 135 };
 136
 137 /*
 138  * getPort: Decide which port to use. There are two possibilities to
 139  * specify a port: integrated in the --telnet-host option with :PORT
 140  * or using the --telnet-port option. The --telnet-port option has
 141  * precedence.
 142  * This code relies upon the fact the url.i_port is 0 if the :PORT
 143  * option is missing from --telnet-host.
 144  */
 145 static int getPort(intf_thread_t *p_intf, vlc_url_t url, int i_port)
 146 {
 147     // Print error if two different ports have been specified
 148     if (url.i_port != 0  &&
 149         i_port != TELNETPORT_DEFAULT &&
 150         url.i_port != i_port )
 151     {
 152         msg_Err( p_intf, "ignoring port %d and using %d", url.i_port,
 153                  i_port);
 154     }
 155     if (i_port != TELNETPORT_DEFAULT)
 156     {
 157         return i_port;
 158     }
 159     if (url.i_port != 0)
 160     {
 161          return url.i_port;
 162     }
 163     return i_port;
 164 }
 165
 166 /*****************************************************************************
 167  * Open: initialize dummy interface
 168  *****************************************************************************/
 169 static int Open( vlc_object_t *p_this )
 170 {
 171     intf_thread_t *p_intf = (intf_thread_t*) p_this;
 172     vlm_t *mediatheque;
 173     char *psz_address;
 174     vlc_url_t url;
 175     int i_telnetport;
 176
 177     if( !(mediatheque = vlm_New( p_intf )) )
 178     {
 179         msg_Err( p_intf, "cannot start VLM" );
 180         return VLC_EGENERIC;
 181     }
 182
 183     msg_Info( p_intf, "using the VLM interface plugin..." );
 184
 185     i_telnetport = config_GetInt( p_intf, "telnet-port" );
 186     psz_address  = config_GetPsz( p_intf, "telnet-host" );
 187
 188     vlc_UrlParse(&url, psz_address, 0);
 189
 190     // There might be two ports given, resolve any potentially
 191     // conflict
 192     url.i_port = getPort(p_intf, url, i_telnetport);
 193
 194     p_intf->p_sys = malloc( sizeof( intf_sys_t ) );
 195     if( ( p_intf->p_sys->pi_fd = net_ListenTCP( p_intf, url.psz_host, url.i_port ) )
 196                 == NULL )
 197     {
 198         msg_Err( p_intf, "cannot listen for telnet" );
 199         vlc_UrlClean(&url);
 200         free( psz_address );
 201         free( p_intf->p_sys );
 202         return VLC_EGENERIC;
 203     }
 204     msg_Info( p_intf,
 205               "telnet interface started on interface %s %d",
 206               url.psz_host, url.i_port );
 207
 208     p_intf->p_sys->i_clients   = 0;
 209     p_intf->p_sys->clients     = NULL;
 210     p_intf->p_sys->mediatheque = mediatheque;
 211     p_intf->pf_run = Run;
 212
 213     vlc_UrlClean(&url);
 214     free( psz_address );
 215     return VLC_SUCCESS;
 216 }
 217
 218 /*****************************************************************************
 219  * Close:
 220  *****************************************************************************/
 221 static void Close( vlc_object_t *p_this )
 222 {
 223     intf_thread_t *p_intf = (intf_thread_t*)p_this;
 224     intf_sys_t    *p_sys  = p_intf->p_sys;
 225     int i;
 226
 227     for( i = 0; i < p_sys->i_clients; i++ )
 228     {
 229         telnet_client_t *cl = p_sys->clients[i];
 230         net_Close( cl->fd );
 231         free( cl );
 232         p_sys->clients[i] = NULL;
 233     }
 234     free( p_sys->clients );
 235
 236     net_ListenClose( p_sys->pi_fd );
 237
 238     vlm_Delete( p_sys->mediatheque );
 239
 240     free( p_sys );
 241 }
 242
 243 /*****************************************************************************
 244  * Run: main loop
 245  *****************************************************************************/
 246 static void Run( intf_thread_t *p_intf )
 247 {
 248     intf_sys_t     *p_sys = p_intf->p_sys;
 249     char           *psz_password;
 250     unsigned        nlisten = 0;
 251
 252     for (const int *pfd = p_sys->pi_fd; *pfd != -1; pfd++)
 253         nlisten++; /* How many listening sockets do we have? */
 254
 255     psz_password = config_GetPsz( p_intf, "telnet-password" );
 256
 257     while( !intf_ShouldDie( p_intf ) )
 258     {
 259         unsigned ncli = p_sys->i_clients;
 260         struct pollfd ufd[ncli + nlisten];
 261
 262         for (unsigned i = 0; i < ncli; i++)
 263         {
 264             telnet_client_t *cl = p_sys->clients[i];
 265
 266             ufd[i].fd = cl->fd;
 267             if( (cl->i_mode == WRITE_MODE_PWD) || (cl->i_mode == WRITE_MODE_CMD) )
 268                 ufd[i].events = POLLOUT;
 269             else
 270                 ufd[i].events = POLLIN;
 271             ufd[i].revents = 0;
 272         }
 273
 274         for (unsigned i = 0; i < nlisten; i++)
 275         {
 276             ufd[ncli + i].fd = p_sys->pi_fd[i];
 277             ufd[ncli + i].events = POLLIN;
 278             ufd[ncli + i].revents = 0;
 279         }
 280
 281         /* FIXME: arbitrary tick */
 282         switch (poll (ufd, sizeof (ufd) / sizeof (ufd[0]), 500))
 283         {
 284             case -1:
 285                 if (net_errno != EINTR)
 286                 {
 287                     msg_Err (p_intf, "network poll error");
 288                     msleep (1000);
 289                     continue;
 290                 }
 291             case 0:
 292                 continue;
 293         }
 294
 295         /* check if there is something to do with the socket */
 296         for (unsigned i = 0; i < ncli; i++)
 297         {
 298             telnet_client_t *cl = p_sys->clients[i];
 299
 300             if (ufd[i].revents & (POLLERR|POLLHUP))
 301             {
 302             drop:
 303                 net_Close( cl->fd );
 304                 TAB_REMOVE( p_intf->p_sys->i_clients ,
 305                             p_intf->p_sys->clients , cl );
 306                 free( cl );
 307                 continue;
 308             }
 309
 310             if (ufd[i].revents & POLLOUT && (cl->i_buffer_write > 0))
 311             {
 312                 ssize_t i_len;
 313
 314                 i_len = send( cl->fd, cl->p_buffer_write ,
 315                               cl->i_buffer_write, 0 );
 316                 if( i_len > 0 )
 317                 {
 318                     cl->p_buffer_write += i_len;
 319                     cl->i_buffer_write -= i_len;
 320                 }
 321             }
 322             if (ufd[i].revents & POLLIN)
 323             {
 324                 bool end = false;
 325                 ssize_t i_recv;
 326
 327                 while( ((i_recv=recv( cl->fd, cl->p_buffer_read, 1, 0 )) > 0) &&
 328                        ((cl->p_buffer_read - cl->buffer_read) < 999) )
 329                 {
 330                     switch( cl->i_tel_cmd )
 331                     {
 332                     case 0:
 333                         switch( *(uint8_t *)cl->p_buffer_read )
 334                         {
 335                         case '\r':
 336                             break;
 337                         case '\n':
 338                             *cl->p_buffer_read = '\n';
 339                             end = true;
 340                             break;
 341                         case TEL_IAC: // telnet specific command
 342                             cl->i_tel_cmd = 1;
 343                             cl->p_buffer_read++;
 344                             break;
 345                         default:
 346                             cl->p_buffer_read++;
 347                             break;
 348                         }
 349                         break;
 350                     case 1:
 351                         switch( *(uint8_t *)cl->p_buffer_read )
 352                         {
 353                         case TEL_WILL: case TEL_WONT:
 354                         case TEL_DO: case TEL_DONT:
 355                             cl->i_tel_cmd++;
 356                             cl->p_buffer_read++;
 357                             break;
 358                         default:
 359                             cl->i_tel_cmd = 0;
 360                             cl->p_buffer_read--;
 361                             break;
 362                         }
 363                         break;
 364                     case 2:
 365                         cl->i_tel_cmd = 0;
 366                         cl->p_buffer_read -= 2;
 367                         break;
 368                     }
 369
 370                     if( end ) break;
 371                 }
 372
 373                 if( (cl->p_buffer_read - cl->buffer_read) == 999 )
 374                 {
 375                     Write_message( cl, NULL, "Line too long\r\n",
 376                                    cl->i_mode + 2 );
 377                 }
 378
 379                 if (i_recv <= 0 && ( end || errno != EAGAIN ) )
 380                     goto drop;
 381             }
 382         }
 383
 384         /* and now we should bidouille the data we received / send */
 385         for(int i = 0 ; i < p_sys->i_clients ; i++ )
 386         {
 387             telnet_client_t *cl = p_sys->clients[i];
 388
 389             if( cl->i_mode >= WRITE_MODE_PWD && cl->i_buffer_write == 0 )
 390             {
 391                // we have finished to send
 392                cl->i_mode -= 2; // corresponding READ MODE
 393             }
 394             else if( cl->i_mode == READ_MODE_PWD &&
 395                      *cl->p_buffer_read == '\n' )
 396             {
 397                 *cl->p_buffer_read = '\0';
 398                 if( !psz_password || !strcmp( psz_password, cl->buffer_read ) )
 399                 {
 400                     Write_message( cl, NULL, "\xff\xfc\x01\r\nWelcome, "
 401                                    "Master\r\n> ", WRITE_MODE_CMD );
 402                 }
 403                 else
 404                 {
 405                     /* wrong password */
 406                     Write_message( cl, NULL,
 407                                    "\r\nWrong password.\r\nPassword: ",
 408                                    WRITE_MODE_PWD );
 409                 }
 410             }
 411             else if( cl->i_mode == READ_MODE_CMD &&
 412                      *cl->p_buffer_read == '\n' )
 413             {
 414                 /* ok, here is a command line */
 415                 if( !strncmp( cl->buffer_read, "logout", 6 ) ||
 416                     !strncmp( cl->buffer_read, "quit", 4 )  ||
 417                     !strncmp( cl->buffer_read, "exit", 4 ) )
 418                 {
 419                     net_Close( cl->fd );
 420                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 421                                 p_intf->p_sys->clients , cl );
 422                     free( cl );
 423                 }
 424                 else if( !strncmp( cl->buffer_read, "shutdown", 8 ) )
 425                 {
 426                     msg_Err( p_intf, "shutdown requested" );
 427                     vlc_object_kill( p_intf->p_libvlc );
 428                 }
 429                 else if( *cl->buffer_read == '@'
 430                           && strchr( cl->buffer_read, ' ' ) )
 431                 {
 432                     /* Module specific commands (use same syntax as in the
 433                      * rc interface) */
 434                     char *psz_name = cl->buffer_read + 1;
 435                     char *psz_cmd, *psz_arg, *psz_msg;
 436                     int i_ret;
 437
 438                     psz_cmd = strchr( cl->buffer_read, ' ' );
 439                     *psz_cmd = '\0';  psz_cmd++;
 440                     if( ( psz_arg = strchr( psz_cmd, '\n' ) ) ) *psz_arg = '\0';
 441                     if( ( psz_arg = strchr( psz_cmd, '\r' ) ) ) *psz_arg = '\0';
 442                     if( ( psz_arg = strchr( psz_cmd, ' ' ) )
 443                         && *psz_arg )
 444                     {
 445                         *psz_arg = '\0';
 446                         psz_arg++;
 447                     }
 448
 449                     i_ret = var_Command( p_intf, psz_name, psz_cmd, psz_arg,
 450                                          &psz_msg );
 451
 452                     if( psz_msg )
 453                     {
 454                         vlm_message_t *message;
 455                         message = vlm_MessageNew( "Module command", psz_msg );
 456                         Write_message( cl, message, NULL, WRITE_MODE_CMD );
 457                         vlm_MessageDelete( message );
 458                         free( psz_msg );
 459                     }
 460                 }
 461                 else
 462                 {
 463                     vlm_message_t *message;
 464
 465                     /* create a standard string */
 466                     *cl->p_buffer_read = '\0';
 467
 468                     vlm_ExecuteCommand( p_sys->mediatheque, cl->buffer_read,
 469                                         &message );
 470                     if( !strncmp( cl->buffer_read, "help", 4 ) )
 471                     {
 472                         vlm_message_t *p_my_help =
 473                             vlm_MessageNew( "Telnet Specific Commands:", NULL );
 474                         vlm_MessageAdd( p_my_help,
 475                             vlm_MessageNew( "logout, quit, exit" , NULL ) );
 476                         vlm_MessageAdd( p_my_help,
 477                             vlm_MessageNew( "shutdown" , NULL ) );
 478                         vlm_MessageAdd( p_my_help,
 479                             vlm_MessageNew( "@moduleinstance command argument",
 480                                              NULL) );
 481                         vlm_MessageAdd( message, p_my_help );
 482                     }
 483                     Write_message( cl, message, NULL, WRITE_MODE_CMD );
 484                     vlm_MessageDelete( message );
 485
 486                 }
 487             }
 488         }
 489
 490         /* handle new connections */
 491         for (unsigned i = 0; i < nlisten; i++)
 492         {
 493             int fd;
 494
 495             if (ufd[ncli + i].revents == 0)
 496                 continue;
 497
 498             fd = net_AcceptSingle (VLC_OBJECT(p_intf), ufd[ncli + i].fd);
 499             if (fd == -1)
 500                 continue;
 501
 502             telnet_client_t *cl = malloc( sizeof( telnet_client_t ));
 503             if (cl == NULL)
 504             {
 505                 net_Close (fd);
 506                 continue;
 507             }
 508
 509             memset( cl, 0, sizeof(telnet_client_t) );
 510             cl->i_tel_cmd = 0;
 511             cl->fd = fd;
 512             cl->buffer_write = NULL;
 513             cl->p_buffer_write = cl->buffer_write;
 514             Write_message( cl, NULL,
 515                            "Password: \xff\xfb\x01" , WRITE_MODE_PWD );
 516             TAB_APPEND( p_sys->i_clients, p_sys->clients, cl );
 517         }
 518     }
 519     free( psz_password );
 520 }
 521
 522 static void Write_message( telnet_client_t *client, vlm_message_t *message,
 523                            const char *string_message, int i_mode )
 524 {
 525     char *psz_message;
 526
 527     client->p_buffer_read = client->buffer_read;
 528     (client->p_buffer_read)[0] = 0; // if (cl->p_buffer_read)[0] = '\n'
 529     free( client->buffer_write );
 530
 531     /* generate the psz_message string */
 532     if( message )
 533     {
 534         /* ok, look for vlm_message_t */
 535         psz_message = MessageToString( message, 0 );
 536     }
 537     else
 538     {
 539         /* it is a basic string_message */
 540         psz_message = strdup( string_message );
 541     }
 542
 543     client->buffer_write = client->p_buffer_write = psz_message;
 544     client->i_buffer_write = strlen( psz_message );
 545     client->i_mode = i_mode;
 546 }
 547
 548 /* We need the level of the message to put a beautiful indentation.
 549  * first level is 0 */
 550 static char *MessageToString( vlm_message_t *message, int i_level )
 551 {
 552 #define STRING_CR "\r\n"
 553 #define STRING_TAIL "> "
 554
 555     char *psz_message;
 556     int i, i_message = sizeof( STRING_TAIL );
 557
 558     if( !message || !message->psz_name )
 559     {
 560         return strdup( STRING_CR STRING_TAIL );
 561     }
 562     else if( !i_level && !message->i_child && !message->psz_value  )
 563     {
 564         /* A command is successful. Don't write anything */
 565         return strdup( /*STRING_CR*/ STRING_TAIL );
 566     }
 567
 568     i_message += strlen( message->psz_name ) + i_level * sizeof( "    " ) + 1;
 569     psz_message = malloc( i_message );
 570     *psz_message = 0;
 571     for( i = 0; i < i_level; i++ ) strcat( psz_message, "    " );
 572     strcat( psz_message, message->psz_name );
 573
 574     if( message->psz_value )
 575     {
 576         i_message += sizeof( " : " ) + strlen( message->psz_value ) +
 577             sizeof( STRING_CR );
 578         psz_message = realloc( psz_message, i_message );
 579         strcat( psz_message, " : " );
 580         strcat( psz_message, message->psz_value );
 581         strcat( psz_message, STRING_CR );
 582     }
 583     else
 584     {
 585         i_message += sizeof( STRING_CR );
 586         psz_message = realloc( psz_message, i_message );
 587         strcat( psz_message, STRING_CR );
 588     }
 589
 590     for( i = 0; i < message->i_child; i++ )
 591     {
 592         char *child_message =
 593             MessageToString( message->child[i], i_level + 1 );
 594
 595         i_message += strlen( child_message );
 596         psz_message = realloc( psz_message, i_message );
 597         strcat( psz_message, child_message );
 598         free( child_message );
 599     }
 600
 601     if( i_level == 0 ) strcat( psz_message, STRING_TAIL );
 602
 603     return psz_message;
 604 }