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, 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     free( psz_address );
 190
 191     // There might be two ports given, resolve any potentially
 192     // conflict
 193     url.i_port = getPort(p_intf, url, i_telnetport);
 194
 195     p_intf->p_sys = malloc( sizeof( intf_sys_t ) );
 196     if( !p_intf->p_sys )
 197     {
 198         vlm_Delete( p_intf->p_sys->mediatheque );
 199         vlc_UrlClean( &url );
 200         return VLC_ENOMEM;
 201     }
 202     if( ( p_intf->p_sys->pi_fd = net_ListenTCP( p_intf, url.psz_host, url.i_port ) ) == NULL )
 203     {
 204         msg_Err( p_intf, "cannot listen for telnet" );
 205         vlm_Delete( p_intf->p_sys->mediatheque );
 206         vlc_UrlClean( &url );
 207         free( p_intf->p_sys );
 208         return VLC_EGENERIC;
 209     }
 210     msg_Info( p_intf,
 211               "telnet interface started on interface %s %d",
 212               url.psz_host, url.i_port );
 213
 214     p_intf->p_sys->i_clients   = 0;
 215     p_intf->p_sys->clients     = NULL;
 216     p_intf->p_sys->mediatheque = mediatheque;
 217     p_intf->pf_run = Run;
 218
 219     vlc_UrlClean( &url );
 220     return VLC_SUCCESS;
 221 }
 222
 223 /*****************************************************************************
 224  * Close:
 225  *****************************************************************************/
 226 static void Close( vlc_object_t *p_this )
 227 {
 228     intf_thread_t *p_intf = (intf_thread_t*)p_this;
 229     intf_sys_t    *p_sys  = p_intf->p_sys;
 230     int i;
 231
 232     for( i = 0; i < p_sys->i_clients; i++ )
 233     {
 234         telnet_client_t *cl = p_sys->clients[i];
 235         net_Close( cl->fd );
 236         free( cl->buffer_write );
 237         free( cl );
 238     }
 239     free( p_sys->clients );
 240
 241     net_ListenClose( p_sys->pi_fd );
 242
 243     vlm_Delete( p_sys->mediatheque );
 244
 245     free( p_sys );
 246 }
 247
 248 /*****************************************************************************
 249  * Run: main loop
 250  *****************************************************************************/
 251 static void Run( intf_thread_t *p_intf )
 252 {
 253     intf_sys_t     *p_sys = p_intf->p_sys;
 254     char           *psz_password;
 255     unsigned        nlisten = 0;
 256
 257     for (const int *pfd = p_sys->pi_fd; *pfd != -1; pfd++)
 258         nlisten++; /* How many listening sockets do we have? */
 259
 260     psz_password = config_GetPsz( p_intf, "telnet-password" );
 261
 262     while( !intf_ShouldDie( p_intf ) )
 263     {
 264         unsigned ncli = p_sys->i_clients;
 265         struct pollfd ufd[ncli + nlisten];
 266
 267         for (unsigned i = 0; i < ncli; i++)
 268         {
 269             telnet_client_t *cl = p_sys->clients[i];
 270
 271             ufd[i].fd = cl->fd;
 272             if( (cl->i_mode == WRITE_MODE_PWD) || (cl->i_mode == WRITE_MODE_CMD) )
 273                 ufd[i].events = POLLOUT;
 274             else
 275                 ufd[i].events = POLLIN;
 276             ufd[i].revents = 0;
 277         }
 278
 279         for (unsigned i = 0; i < nlisten; i++)
 280         {
 281             ufd[ncli + i].fd = p_sys->pi_fd[i];
 282             ufd[ncli + i].events = POLLIN;
 283             ufd[ncli + i].revents = 0;
 284         }
 285
 286         /* FIXME: arbitrary tick */
 287         switch (poll (ufd, sizeof (ufd) / sizeof (ufd[0]), 500))
 288         {
 289             case -1:
 290                 if (net_errno != EINTR)
 291                 {
 292                     msg_Err (p_intf, "network poll error");
 293                     msleep (1000);
 294                     continue;
 295                 }
 296             case 0:
 297                 continue;
 298         }
 299
 300         /* check if there is something to do with the socket */
 301         for (unsigned i = 0; i < ncli; i++)
 302         {
 303             telnet_client_t *cl = p_sys->clients[i];
 304
 305             if (ufd[i].revents & (POLLERR|POLLHUP))
 306             {
 307             drop:
 308                 net_Close( cl->fd );
 309                 TAB_REMOVE( p_intf->p_sys->i_clients ,
 310                             p_intf->p_sys->clients , cl );
 311                 free( cl );
 312                 continue;
 313             }
 314
 315             if (ufd[i].revents & POLLOUT && (cl->i_buffer_write > 0))
 316             {
 317                 ssize_t i_len;
 318
 319                 i_len = send( cl->fd, cl->p_buffer_write ,
 320                               cl->i_buffer_write, 0 );
 321                 if( i_len > 0 )
 322                 {
 323                     cl->p_buffer_write += i_len;
 324                     cl->i_buffer_write -= i_len;
 325                 }
 326             }
 327             if (ufd[i].revents & POLLIN)
 328             {
 329                 bool end = false;
 330                 ssize_t i_recv;
 331
 332                 while( ((i_recv=recv( cl->fd, cl->p_buffer_read, 1, 0 )) > 0) &&
 333                        ((cl->p_buffer_read - cl->buffer_read) < 999) )
 334                 {
 335                     switch( cl->i_tel_cmd )
 336                     {
 337                     case 0:
 338                         switch( *(uint8_t *)cl->p_buffer_read )
 339                         {
 340                         case '\r':
 341                             break;
 342                         case '\n':
 343                             *cl->p_buffer_read = '\n';
 344                             end = true;
 345                             break;
 346                         case TEL_IAC: // telnet specific command
 347                             cl->i_tel_cmd = 1;
 348                             cl->p_buffer_read++;
 349                             break;
 350                         default:
 351                             cl->p_buffer_read++;
 352                             break;
 353                         }
 354                         break;
 355                     case 1:
 356                         switch( *(uint8_t *)cl->p_buffer_read )
 357                         {
 358                         case TEL_WILL: case TEL_WONT:
 359                         case TEL_DO: case TEL_DONT:
 360                             cl->i_tel_cmd++;
 361                             cl->p_buffer_read++;
 362                             break;
 363                         default:
 364                             cl->i_tel_cmd = 0;
 365                             cl->p_buffer_read--;
 366                             break;
 367                         }
 368                         break;
 369                     case 2:
 370                         cl->i_tel_cmd = 0;
 371                         cl->p_buffer_read -= 2;
 372                         break;
 373                     }
 374
 375                     if( end ) break;
 376                 }
 377
 378                 if( (cl->p_buffer_read - cl->buffer_read) == 999 )
 379                 {
 380                     Write_message( cl, NULL, "Line too long\r\n",
 381                                    cl->i_mode + 2 );
 382                 }
 383
 384                 if (i_recv <= 0 && ( end || errno != EAGAIN ) )
 385                     goto drop;
 386             }
 387         }
 388
 389         /* and now we should bidouille the data we received / send */
 390         for(int i = 0 ; i < p_sys->i_clients ; i++ )
 391         {
 392             telnet_client_t *cl = p_sys->clients[i];
 393
 394             if( cl->i_mode >= WRITE_MODE_PWD && cl->i_buffer_write == 0 )
 395             {
 396                // we have finished to send
 397                cl->i_mode -= 2; // corresponding READ MODE
 398             }
 399             else if( cl->i_mode == READ_MODE_PWD &&
 400                      *cl->p_buffer_read == '\n' )
 401             {
 402                 *cl->p_buffer_read = '\0';
 403                 if( !psz_password || !strcmp( psz_password, cl->buffer_read ) )
 404                 {
 405                     Write_message( cl, NULL, "\xff\xfc\x01\r\nWelcome, "
 406                                    "Master\r\n> ", WRITE_MODE_CMD );
 407                 }
 408                 else
 409                 {
 410                     /* wrong password */
 411                     Write_message( cl, NULL,
 412                                    "\r\nWrong password.\r\nPassword: ",
 413                                    WRITE_MODE_PWD );
 414                 }
 415             }
 416             else if( cl->i_mode == READ_MODE_CMD &&
 417                      *cl->p_buffer_read == '\n' )
 418             {
 419                 /* ok, here is a command line */
 420                 if( !strncmp( cl->buffer_read, "logout", 6 ) ||
 421                     !strncmp( cl->buffer_read, "quit", 4 )  ||
 422                     !strncmp( cl->buffer_read, "exit", 4 ) )
 423                 {
 424                     net_Close( cl->fd );
 425                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 426                                 p_intf->p_sys->clients , cl );
 427                     free( cl->buffer_write );
 428                     free( cl );
 429                 }
 430                 else if( !strncmp( cl->buffer_read, "shutdown", 8 ) )
 431                 {
 432                     msg_Err( p_intf, "shutdown requested" );
 433                     vlc_object_kill( p_intf->p_libvlc );
 434                 }
 435                 else if( *cl->buffer_read == '@'
 436                           && strchr( cl->buffer_read, ' ' ) )
 437                 {
 438                     /* Module specific commands (use same syntax as in the
 439                      * rc interface) */
 440                     char *psz_name = cl->buffer_read + 1;
 441                     char *psz_cmd, *psz_arg, *psz_msg;
 442                     int i_ret;
 443
 444                     psz_cmd = strchr( cl->buffer_read, ' ' );
 445                     *psz_cmd = '\0';  psz_cmd++;
 446                     if( ( psz_arg = strchr( psz_cmd, '\n' ) ) ) *psz_arg = '\0';
 447                     if( ( psz_arg = strchr( psz_cmd, '\r' ) ) ) *psz_arg = '\0';
 448                     if( ( psz_arg = strchr( psz_cmd, ' ' ) )
 449                         && *psz_arg )
 450                     {
 451                         *psz_arg = '\0';
 452                         psz_arg++;
 453                     }
 454
 455                     i_ret = var_Command( p_intf, psz_name, psz_cmd, psz_arg,
 456                                          &psz_msg );
 457
 458                     if( psz_msg )
 459                     {
 460                         vlm_message_t *message;
 461                         message = vlm_MessageNew( "Module command", psz_msg );
 462                         Write_message( cl, message, NULL, WRITE_MODE_CMD );
 463                         vlm_MessageDelete( message );
 464                         free( psz_msg );
 465                     }
 466                 }
 467                 else
 468                 {
 469                     vlm_message_t *message;
 470
 471                     /* create a standard string */
 472                     *cl->p_buffer_read = '\0';
 473
 474                     vlm_ExecuteCommand( p_sys->mediatheque, cl->buffer_read,
 475                                         &message );
 476                     if( !strncmp( cl->buffer_read, "help", 4 ) )
 477                     {
 478                         vlm_message_t *p_my_help =
 479                             vlm_MessageNew( "Telnet Specific Commands:", NULL );
 480                         vlm_MessageAdd( p_my_help,
 481                             vlm_MessageNew( "logout, quit, exit" , NULL ) );
 482                         vlm_MessageAdd( p_my_help,
 483                             vlm_MessageNew( "shutdown" , NULL ) );
 484                         vlm_MessageAdd( p_my_help,
 485                             vlm_MessageNew( "@moduleinstance command argument",
 486                                              NULL) );
 487                         vlm_MessageAdd( message, p_my_help );
 488                     }
 489                     Write_message( cl, message, NULL, WRITE_MODE_CMD );
 490                     vlm_MessageDelete( message );
 491                 }
 492             }
 493         }
 494
 495         /* handle new connections */
 496         for (unsigned i = 0; i < nlisten; i++)
 497         {
 498             int fd;
 499
 500             if (ufd[ncli + i].revents == 0)
 501                 continue;
 502
 503             fd = net_AcceptSingle (VLC_OBJECT(p_intf), ufd[ncli + i].fd);
 504             if (fd == -1)
 505                 continue;
 506
 507             telnet_client_t *cl = malloc( sizeof( telnet_client_t ));
 508             if (cl == NULL)
 509             {
 510                 net_Close (fd);
 511                 continue;
 512             }
 513
 514             memset( cl, 0, sizeof(telnet_client_t) );
 515             cl->i_tel_cmd = 0;
 516             cl->fd = fd;
 517             cl->buffer_write = NULL;
 518             cl->p_buffer_write = cl->buffer_write;
 519             Write_message( cl, NULL,
 520                            "Password: \xff\xfb\x01" , WRITE_MODE_PWD );
 521             TAB_APPEND( p_sys->i_clients, p_sys->clients, cl );
 522         }
 523     }
 524     free( psz_password );
 525 }
 526
 527 static void Write_message( telnet_client_t *client, vlm_message_t *message,
 528                            const char *string_message, int i_mode )
 529 {
 530     char *psz_message;
 531
 532     client->p_buffer_read = client->buffer_read;
 533     (client->p_buffer_read)[0] = 0; // if (cl->p_buffer_read)[0] = '\n'
 534     free( client->buffer_write );
 535
 536     /* generate the psz_message string */
 537     if( message )
 538     {
 539         /* ok, look for vlm_message_t */
 540         psz_message = MessageToString( message, 0 );
 541     }
 542     else
 543     {
 544         /* it is a basic string_message */
 545         psz_message = strdup( string_message );
 546     }
 547
 548     client->buffer_write = client->p_buffer_write = psz_message;
 549     client->i_buffer_write = strlen( psz_message );
 550     client->i_mode = i_mode;
 551 }
 552
 553 /* We need the level of the message to put a beautiful indentation.
 554  * first level is 0 */
 555 static char *MessageToString( vlm_message_t *message, int i_level )
 556 {
 557 #define STRING_CR "\r\n"
 558 #define STRING_TAIL "> "
 559
 560     char *psz_message;
 561     int i, i_message = sizeof( STRING_TAIL );
 562
 563     if( !message || !message->psz_name )
 564     {
 565         return strdup( STRING_CR STRING_TAIL );
 566     }
 567     else if( !i_level && !message->i_child && !message->psz_value  )
 568     {
 569         /* A command is successful. Don't write anything */
 570         return strdup( /*STRING_CR*/ STRING_TAIL );
 571     }
 572
 573     i_message += strlen( message->psz_name ) + i_level * sizeof( "    " ) + 1;
 574     psz_message = malloc( i_message );
 575     *psz_message = 0;
 576     for( i = 0; i < i_level; i++ ) strcat( psz_message, "    " );
 577     strcat( psz_message, message->psz_name );
 578
 579     if( message->psz_value )
 580     {
 581         i_message += sizeof( " : " ) + strlen( message->psz_value ) +
 582             sizeof( STRING_CR );
 583         psz_message = realloc( psz_message, i_message );
 584         strcat( psz_message, " : " );
 585         strcat( psz_message, message->psz_value );
 586         strcat( psz_message, STRING_CR );
 587     }
 588     else
 589     {
 590         i_message += sizeof( STRING_CR );
 591         psz_message = realloc( psz_message, i_message );
 592         strcat( psz_message, STRING_CR );
 593     }
 594
 595     for( i = 0; i < message->i_child; i++ )
 596     {
 597         char *child_message =
 598             MessageToString( message->child[i], i_level + 1 );
 599
 600         i_message += strlen( child_message );
 601         psz_message = realloc( psz_message, i_message );
 602         strcat( psz_message, child_message );
 603         free( child_message );
 604     }
 605
 606     if( i_level == 0 ) strcat( psz_message, STRING_TAIL );
 607
 608     return psz_message;
 609 }