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_common.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, const vlc_url_t *url, int i_port)
 146 {
 147     if (i_port == TELNETPORT_DEFAULT && url->i_port != 0)
 148         i_port = url->i_port;
 149     if (url->i_port != 0 && url->i_port != i_port)
 150         // Print error if two different ports have been specified
 151         msg_Warn( p_intf, "ignoring port %d (using %d)", url->i_port, i_port );
 152     return i_port;
 153 }
 154
 155 /*****************************************************************************
 156  * Open: initialize dummy interface
 157  *****************************************************************************/
 158 static int Open( vlc_object_t *p_this )
 159 {
 160     intf_thread_t *p_intf = (intf_thread_t*) p_this;
 161     vlm_t *mediatheque;
 162     char *psz_address;
 163     vlc_url_t url;
 164     int i_telnetport;
 165
 166     if( !(mediatheque = vlm_New( p_intf )) )
 167     {
 168         msg_Err( p_intf, "cannot start VLM" );
 169         return VLC_EGENERIC;
 170     }
 171
 172     msg_Info( p_intf, "using the VLM interface plugin..." );
 173
 174     i_telnetport = config_GetInt( p_intf, "telnet-port" );
 175     psz_address  = config_GetPsz( p_intf, "telnet-host" );
 176
 177     vlc_UrlParse(&url, psz_address, 0);
 178     free( psz_address );
 179
 180     // There might be two ports given, resolve any potentially
 181     // conflict
 182     url.i_port = getPort(p_intf, &url, i_telnetport);
 183
 184     p_intf->p_sys = malloc( sizeof( intf_sys_t ) );
 185     if( !p_intf->p_sys )
 186     {
 187         vlm_Delete( mediatheque );
 188         vlc_UrlClean( &url );
 189         return VLC_ENOMEM;
 190     }
 191     if( ( p_intf->p_sys->pi_fd = net_ListenTCP( p_intf, url.psz_host, url.i_port ) ) == NULL )
 192     {
 193         msg_Err( p_intf, "cannot listen for telnet" );
 194         vlm_Delete( mediatheque );
 195         vlc_UrlClean( &url );
 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     return VLC_SUCCESS;
 210 }
 211
 212 /*****************************************************************************
 213  * Close:
 214  *****************************************************************************/
 215 static void Close( vlc_object_t *p_this )
 216 {
 217     intf_thread_t *p_intf = (intf_thread_t*)p_this;
 218     intf_sys_t    *p_sys  = p_intf->p_sys;
 219     int i;
 220
 221     for( i = 0; i < p_sys->i_clients; i++ )
 222     {
 223         telnet_client_t *cl = p_sys->clients[i];
 224         net_Close( cl->fd );
 225         free( cl->buffer_write );
 226         free( cl );
 227     }
 228     free( p_sys->clients );
 229
 230     net_ListenClose( p_sys->pi_fd );
 231
 232     vlm_Delete( p_sys->mediatheque );
 233
 234     free( p_sys );
 235 }
 236
 237 /*****************************************************************************
 238  * Run: main loop
 239  *****************************************************************************/
 240 static void Run( intf_thread_t *p_intf )
 241 {
 242     intf_sys_t     *p_sys = p_intf->p_sys;
 243     char           *psz_password;
 244     unsigned        nlisten = 0;
 245
 246     for (const int *pfd = p_sys->pi_fd; *pfd != -1; pfd++)
 247         nlisten++; /* How many listening sockets do we have? */
 248
 249     psz_password = config_GetPsz( p_intf, "telnet-password" );
 250
 251     while( !intf_ShouldDie( p_intf ) )
 252     {
 253         unsigned ncli = p_sys->i_clients;
 254         struct pollfd ufd[ncli + nlisten];
 255
 256         for (unsigned i = 0; i < ncli; i++)
 257         {
 258             telnet_client_t *cl = p_sys->clients[i];
 259
 260             ufd[i].fd = cl->fd;
 261             if( (cl->i_mode == WRITE_MODE_PWD) || (cl->i_mode == WRITE_MODE_CMD) )
 262                 ufd[i].events = POLLOUT;
 263             else
 264                 ufd[i].events = POLLIN;
 265             ufd[i].revents = 0;
 266         }
 267
 268         for (unsigned i = 0; i < nlisten; i++)
 269         {
 270             ufd[ncli + i].fd = p_sys->pi_fd[i];
 271             ufd[ncli + i].events = POLLIN;
 272             ufd[ncli + i].revents = 0;
 273         }
 274
 275         /* FIXME: arbitrary tick */
 276         switch (poll (ufd, sizeof (ufd) / sizeof (ufd[0]), 500))
 277         {
 278             case -1:
 279                 if (net_errno != EINTR)
 280                 {
 281                     msg_Err (p_intf, "network poll error");
 282                     msleep (1000);
 283                     continue;
 284                 }
 285             case 0:
 286                 continue;
 287         }
 288
 289         /* check if there is something to do with the socket */
 290         for (unsigned i = 0; i < ncli; i++)
 291         {
 292             telnet_client_t *cl = p_sys->clients[i];
 293
 294             if (ufd[i].revents & (POLLERR|POLLHUP))
 295             {
 296             drop:
 297                 net_Close( cl->fd );
 298                 TAB_REMOVE( p_intf->p_sys->i_clients ,
 299                             p_intf->p_sys->clients , cl );
 300                 free( cl );
 301                 continue;
 302             }
 303
 304             if (ufd[i].revents & POLLOUT && (cl->i_buffer_write > 0))
 305             {
 306                 ssize_t i_len;
 307
 308                 i_len = send( cl->fd, cl->p_buffer_write ,
 309                               cl->i_buffer_write, 0 );
 310                 if( i_len > 0 )
 311                 {
 312                     cl->p_buffer_write += i_len;
 313                     cl->i_buffer_write -= i_len;
 314                 }
 315             }
 316             if (ufd[i].revents & POLLIN)
 317             {
 318                 bool end = false;
 319                 ssize_t i_recv;
 320
 321                 while( ((i_recv=recv( cl->fd, cl->p_buffer_read, 1, 0 )) > 0) &&
 322                        ((cl->p_buffer_read - cl->buffer_read) < 999) )
 323                 {
 324                     switch( cl->i_tel_cmd )
 325                     {
 326                     case 0:
 327                         switch( *(uint8_t *)cl->p_buffer_read )
 328                         {
 329                         case '\r':
 330                             break;
 331                         case '\n':
 332                             *cl->p_buffer_read = '\n';
 333                             end = true;
 334                             break;
 335                         case TEL_IAC: // telnet specific command
 336                             cl->i_tel_cmd = 1;
 337                             cl->p_buffer_read++;
 338                             break;
 339                         default:
 340                             cl->p_buffer_read++;
 341                             break;
 342                         }
 343                         break;
 344                     case 1:
 345                         switch( *(uint8_t *)cl->p_buffer_read )
 346                         {
 347                         case TEL_WILL: case TEL_WONT:
 348                         case TEL_DO: case TEL_DONT:
 349                             cl->i_tel_cmd++;
 350                             cl->p_buffer_read++;
 351                             break;
 352                         default:
 353                             cl->i_tel_cmd = 0;
 354                             cl->p_buffer_read--;
 355                             break;
 356                         }
 357                         break;
 358                     case 2:
 359                         cl->i_tel_cmd = 0;
 360                         cl->p_buffer_read -= 2;
 361                         break;
 362                     }
 363
 364                     if( end ) break;
 365                 }
 366
 367                 if( (cl->p_buffer_read - cl->buffer_read) == 999 )
 368                 {
 369                     Write_message( cl, NULL, "Line too long\r\n",
 370                                    cl->i_mode + 2 );
 371                 }
 372
 373                 if (i_recv <= 0 && ( end || errno != EAGAIN ) )
 374                     goto drop;
 375             }
 376         }
 377
 378         /* and now we should bidouille the data we received / send */
 379         for(int i = 0 ; i < p_sys->i_clients ; i++ )
 380         {
 381             telnet_client_t *cl = p_sys->clients[i];
 382
 383             if( cl->i_mode >= WRITE_MODE_PWD && cl->i_buffer_write == 0 )
 384             {
 385                // we have finished to send
 386                cl->i_mode -= 2; // corresponding READ MODE
 387             }
 388             else if( cl->i_mode == READ_MODE_PWD &&
 389                      *cl->p_buffer_read == '\n' )
 390             {
 391                 *cl->p_buffer_read = '\0';
 392                 if( !psz_password || !strcmp( psz_password, cl->buffer_read ) )
 393                 {
 394                     Write_message( cl, NULL, "\xff\xfc\x01\r\nWelcome, "
 395                                    "Master\r\n> ", WRITE_MODE_CMD );
 396                 }
 397                 else
 398                 {
 399                     /* wrong password */
 400                     Write_message( cl, NULL,
 401                                    "\r\nWrong password.\r\nPassword: ",
 402                                    WRITE_MODE_PWD );
 403                 }
 404             }
 405             else if( cl->i_mode == READ_MODE_CMD &&
 406                      *cl->p_buffer_read == '\n' )
 407             {
 408                 /* ok, here is a command line */
 409                 if( !strncmp( cl->buffer_read, "logout", 6 ) ||
 410                     !strncmp( cl->buffer_read, "quit", 4 )  ||
 411                     !strncmp( cl->buffer_read, "exit", 4 ) )
 412                 {
 413                     net_Close( cl->fd );
 414                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 415                                 p_intf->p_sys->clients , cl );
 416                     free( cl->buffer_write );
 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         /* handle new connections */
 485         for (unsigned i = 0; i < nlisten; i++)
 486         {
 487             int fd;
 488
 489             if (ufd[ncli + i].revents == 0)
 490                 continue;
 491
 492             fd = net_AcceptSingle (VLC_OBJECT(p_intf), ufd[ncli + i].fd);
 493             if (fd == -1)
 494                 continue;
 495
 496             telnet_client_t *cl = malloc( sizeof( telnet_client_t ));
 497             if (cl == NULL)
 498             {
 499                 net_Close (fd);
 500                 continue;
 501             }
 502
 503             memset( cl, 0, sizeof(telnet_client_t) );
 504             cl->i_tel_cmd = 0;
 505             cl->fd = fd;
 506             cl->buffer_write = NULL;
 507             cl->p_buffer_write = cl->buffer_write;
 508             Write_message( cl, NULL,
 509                            "Password: \xff\xfb\x01" , WRITE_MODE_PWD );
 510             TAB_APPEND( p_sys->i_clients, p_sys->clients, cl );
 511         }
 512     }
 513     free( psz_password );
 514 }
 515
 516 static void Write_message( telnet_client_t *client, vlm_message_t *message,
 517                            const char *string_message, int i_mode )
 518 {
 519     char *psz_message;
 520
 521     client->p_buffer_read = client->buffer_read;
 522     (client->p_buffer_read)[0] = 0; // if (cl->p_buffer_read)[0] = '\n'
 523     free( client->buffer_write );
 524
 525     /* generate the psz_message string */
 526     if( message )
 527     {
 528         /* ok, look for vlm_message_t */
 529         psz_message = MessageToString( message, 0 );
 530     }
 531     else
 532     {
 533         /* it is a basic string_message */
 534         psz_message = strdup( string_message );
 535     }
 536
 537     client->buffer_write = client->p_buffer_write = psz_message;
 538     client->i_buffer_write = strlen( psz_message );
 539     client->i_mode = i_mode;
 540 }
 541
 542 /* We need the level of the message to put a beautiful indentation.
 543  * first level is 0 */
 544 static char *MessageToString( vlm_message_t *message, int i_level )
 545 {
 546 #define STRING_CR "\r\n"
 547 #define STRING_TAIL "> "
 548
 549     char *psz_message;
 550     int i, i_message = sizeof( STRING_TAIL );
 551
 552     if( !message || !message->psz_name )
 553     {
 554         return strdup( STRING_CR STRING_TAIL );
 555     }
 556     else if( !i_level && !message->i_child && !message->psz_value  )
 557     {
 558         /* A command is successful. Don't write anything */
 559         return strdup( /*STRING_CR*/ STRING_TAIL );
 560     }
 561
 562     i_message += strlen( message->psz_name ) + i_level * sizeof( "    " ) + 1;
 563     psz_message = malloc( i_message );
 564     *psz_message = 0;
 565     for( i = 0; i < i_level; i++ ) strcat( psz_message, "    " );
 566     strcat( psz_message, message->psz_name );
 567
 568     if( message->psz_value )
 569     {
 570         i_message += sizeof( " : " ) + strlen( message->psz_value ) +
 571             sizeof( STRING_CR );
 572         psz_message = realloc( psz_message, i_message );
 573         strcat( psz_message, " : " );
 574         strcat( psz_message, message->psz_value );
 575         strcat( psz_message, STRING_CR );
 576     }
 577     else
 578     {
 579         i_message += sizeof( STRING_CR );
 580         psz_message = realloc( psz_message, i_message );
 581         strcat( psz_message, STRING_CR );
 582     }
 583
 584     for( i = 0; i < message->i_child; i++ )
 585     {
 586         char *child_message =
 587             MessageToString( message->child[i], i_level + 1 );
 588
 589         i_message += strlen( child_message );
 590         psz_message = realloc( psz_message, i_message );
 591         strcat( psz_message, child_message );
 592         free( child_message );
 593     }
 594
 595     if( i_level == 0 ) strcat( psz_message, STRING_TAIL );
 596
 597     return psz_message;
 598 }