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