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