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 <assert.h>
  34
  35 #include <vlc_common.h>
  36 #include <vlc_plugin.h>
  37 #include <vlc_interface.h>
  38 #include <vlc_input.h>
  39 #include <vlc_memory.h>
  40
  41 #include <stdbool.h>
  42 #include <sys/stat.h>
  43
  44 #include <errno.h>
  45 #include <fcntl.h>
  46
  47 #ifdef HAVE_SYS_TIME_H
  48 #    include <sys/time.h>
  49 #endif
  50
  51 #ifdef HAVE_UNISTD_H
  52 #   include <unistd.h>
  53 #endif
  54 #ifdef HAVE_POLL
  55 #   include <poll.h>
  56 #endif
  57
  58 #include <vlc_network.h>
  59 #include <vlc_url.h>
  60 #include <vlc_vlm.h>
  61
  62 #define READ_MODE_PWD 1
  63 #define READ_MODE_CMD 2
  64 #define WRITE_MODE_PWD 3 // when we write the word "Password:"
  65 #define WRITE_MODE_CMD 4
  66
  67 /* telnet commands */
  68 #define TEL_WILL    251
  69 #define TEL_WONT    252
  70 #define TEL_DO      253
  71 #define TEL_DONT    254
  72 #define TEL_IAC     255
  73 #define TEL_ECHO    1
  74
  75 /*****************************************************************************
  76  * Module descriptor
  77  *****************************************************************************/
  78 static int  Open ( vlc_object_t * );
  79 static void Close( vlc_object_t * );
  80
  81 #define TELNETHOST_TEXT N_( "Host" )
  82 #define TELNETHOST_LONGTEXT N_( "This is the host on which the " \
  83     "interface will listen. It defaults to all network interfaces (0.0.0.0)." \
  84     " If you want this interface to be available only on the local " \
  85     "machine, enter \"127.0.0.1\"." )
  86 #define TELNETPORT_TEXT N_( "Port" )
  87 #define TELNETPORT_LONGTEXT N_( "This is the TCP port on which this " \
  88     "interface will listen. It defaults to 4212." )
  89 #define TELNETPORT_DEFAULT 4212
  90 #define TELNETPWD_TEXT N_( "Password" )
  91 #define TELNETPWD_LONGTEXT N_( "A single administration password is used " \
  92     "to protect this interface. The default value is \"admin\"." )
  93 #define TELNETPWD_DEFAULT "admin"
  94
  95 vlc_module_begin ()
  96     set_shortname( "Telnet" )
  97     set_category( CAT_INTERFACE )
  98     set_subcategory( SUBCAT_INTERFACE_CONTROL )
  99     add_string( "telnet-host", "", NULL, TELNETHOST_TEXT,
 100                  TELNETHOST_LONGTEXT, true )
 101     add_integer( "telnet-port", TELNETPORT_DEFAULT, NULL, TELNETPORT_TEXT,
 102                  TELNETPORT_LONGTEXT, true )
 103     add_password( "telnet-password", TELNETPWD_DEFAULT, NULL, TELNETPWD_TEXT,
 104                 TELNETPWD_LONGTEXT, true )
 105     set_description( N_("VLM remote control interface") )
 106     add_category_hint( "VLM", NULL, false )
 107     set_capability( "interface", 0 )
 108     set_callbacks( Open , Close )
 109 vlc_module_end ()
 110
 111 /*****************************************************************************
 112  * Local prototypes.
 113  *****************************************************************************/
 114 static void Run( intf_thread_t * );
 115
 116 typedef struct
 117 {
 118     int        i_mode; /* read or write */
 119     int        fd;
 120     char       buffer_read[1000]; // 1000 byte per command should be sufficient
 121     char      *buffer_write;
 122     char      *p_buffer_read;
 123     char      *p_buffer_write; // the position in the buffer
 124     int        i_buffer_write; // the number of byte we still have to send
 125     int        i_tel_cmd; // for specific telnet commands
 126
 127 } telnet_client_t;
 128
 129 static char *MessageToString( vlm_message_t *, int );
 130 static void Write_message( telnet_client_t *, vlm_message_t *, const char *, int );
 131
 132 struct intf_sys_t
 133 {
 134    telnet_client_t **clients;
 135    int             i_clients;
 136    int             *pi_fd;
 137    vlm_t           *mediatheque;
 138 };
 139
 140 /*
 141  * getPort: Decide which port to use. There are two possibilities to
 142  * specify a port: integrated in the --telnet-host option with :PORT
 143  * or using the --telnet-port option. The --telnet-port option has
 144  * precedence.
 145  * This code relies upon the fact the url.i_port is 0 if the :PORT
 146  * option is missing from --telnet-host.
 147  */
 148 static int getPort(intf_thread_t *p_intf, const vlc_url_t *url, int i_port)
 149 {
 150     if (i_port == TELNETPORT_DEFAULT && url->i_port != 0)
 151         i_port = url->i_port;
 152     if (url->i_port != 0 && url->i_port != i_port)
 153         // Print error if two different ports have been specified
 154         msg_Warn( p_intf, "ignoring port %d (using %d)", url->i_port, i_port );
 155     return i_port;
 156 }
 157
 158 /*****************************************************************************
 159  * Open: initialize dummy interface
 160  *****************************************************************************/
 161 static int Open( vlc_object_t *p_this )
 162 {
 163     intf_thread_t *p_intf = (intf_thread_t*) p_this;
 164     vlm_t *mediatheque;
 165     char *psz_address;
 166     vlc_url_t url;
 167     int i_telnetport;
 168
 169     if( !(mediatheque = vlm_New( p_intf )) )
 170     {
 171         msg_Err( p_intf, "cannot start VLM" );
 172         return VLC_EGENERIC;
 173     }
 174
 175     msg_Info( p_intf, "using the VLM interface plugin..." );
 176
 177     i_telnetport = config_GetInt( p_intf, "telnet-port" );
 178     psz_address  = config_GetPsz( p_intf, "telnet-host" );
 179
 180     vlc_UrlParse(&url, psz_address, 0);
 181     free( psz_address );
 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 )
 189     {
 190         vlm_Delete( mediatheque );
 191         vlc_UrlClean( &url );
 192         return VLC_ENOMEM;
 193     }
 194     if( ( p_intf->p_sys->pi_fd = net_ListenTCP( p_intf, url.psz_host, url.i_port ) ) == NULL )
 195     {
 196         msg_Err( p_intf, "cannot listen for telnet" );
 197         vlm_Delete( mediatheque );
 198         vlc_UrlClean( &url );
 199         free( p_intf->p_sys );
 200         return VLC_EGENERIC;
 201     }
 202     msg_Info( p_intf,
 203               "telnet interface started on interface %s %d",
 204               url.psz_host, url.i_port );
 205
 206     p_intf->p_sys->i_clients   = 0;
 207     p_intf->p_sys->clients     = NULL;
 208     p_intf->p_sys->mediatheque = mediatheque;
 209     p_intf->pf_run = Run;
 210
 211     vlc_UrlClean( &url );
 212     return VLC_SUCCESS;
 213 }
 214
 215 /*****************************************************************************
 216  * Close:
 217  *****************************************************************************/
 218 static void Close( vlc_object_t *p_this )
 219 {
 220     intf_thread_t *p_intf = (intf_thread_t*)p_this;
 221     intf_sys_t    *p_sys  = p_intf->p_sys;
 222     int i;
 223
 224     for( i = 0; i < p_sys->i_clients; i++ )
 225     {
 226         telnet_client_t *cl = p_sys->clients[i];
 227         net_Close( cl->fd );
 228         free( cl->buffer_write );
 229         free( cl );
 230     }
 231     free( p_sys->clients );
 232
 233     net_ListenClose( p_sys->pi_fd );
 234
 235     vlm_Delete( p_sys->mediatheque );
 236
 237     free( p_sys );
 238 }
 239
 240 /*****************************************************************************
 241  * Run: main loop
 242  *****************************************************************************/
 243 static void Run( intf_thread_t *p_intf )
 244 {
 245     intf_sys_t     *p_sys = p_intf->p_sys;
 246     char           *psz_password;
 247     unsigned        nlisten = 0;
 248
 249     for (const int *pfd = p_sys->pi_fd; *pfd != -1; pfd++)
 250         nlisten++; /* How many listening sockets do we have? */
 251
 252     /* FIXME: make sure config_* is cancel-safe */
 253     psz_password = config_GetPsz( p_intf, "telnet-password" );
 254     vlc_cleanup_push( free, psz_password );
 255
 256     for( ;; )
 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         switch (poll (ufd, sizeof (ufd) / sizeof (ufd[0]), -1))
 281         {
 282             case -1:
 283                 if (net_errno != EINTR)
 284                 {
 285                     msg_Err (p_intf, "network poll error");
 286 #ifndef WIN32
 287                     pause ();  /* We are screwed! */
 288 #else
 289                     abort (); /* We are even more screwed! (no pause() in win32) */
 290 #endif
 291                     break;
 292                 }
 293             case 0:
 294                 continue;
 295         }
 296
 297         int canc = vlc_savecancel ();
 298         /* check if there is something to do with the socket */
 299         for (unsigned i = 0; i < ncli; i++)
 300         {
 301             telnet_client_t *cl = p_sys->clients[i];
 302
 303             if (ufd[i].revents & (POLLERR|POLLHUP))
 304             {
 305             drop:
 306                 net_Close( cl->fd );
 307                 TAB_REMOVE( p_intf->p_sys->i_clients ,
 308                             p_intf->p_sys->clients , cl );
 309                 free( cl->buffer_write );
 310                 free( cl );
 311                 continue;
 312             }
 313
 314             if (ufd[i].revents & POLLOUT && (cl->i_buffer_write > 0))
 315             {
 316                 ssize_t i_len;
 317
 318                 i_len = send( cl->fd, cl->p_buffer_write ,
 319                               cl->i_buffer_write, 0 );
 320                 if( i_len > 0 )
 321                 {
 322                     cl->p_buffer_write += i_len;
 323                     cl->i_buffer_write -= i_len;
 324                 }
 325             }
 326             if (ufd[i].revents & POLLIN)
 327             {
 328                 bool end = false;
 329                 ssize_t i_recv;
 330
 331                 while( ((i_recv=recv( cl->fd, cl->p_buffer_read, 1, 0 )) > 0) &&
 332                        ((cl->p_buffer_read - cl->buffer_read) < 999) )
 333                 {
 334                     switch( cl->i_tel_cmd )
 335                     {
 336                     case 0:
 337                         switch( *(uint8_t *)cl->p_buffer_read )
 338                         {
 339                         case '\r':
 340                             break;
 341                         case '\n':
 342                             *cl->p_buffer_read = '\n';
 343                             end = true;
 344                             break;
 345                         case TEL_IAC: // telnet specific command
 346                             cl->i_tel_cmd = 1;
 347                             cl->p_buffer_read++;
 348                             break;
 349                         default:
 350                             cl->p_buffer_read++;
 351                             break;
 352                         }
 353                         break;
 354                     case 1:
 355                         switch( *(uint8_t *)cl->p_buffer_read )
 356                         {
 357                         case TEL_WILL: case TEL_WONT:
 358                         case TEL_DO: case TEL_DONT:
 359                             cl->i_tel_cmd++;
 360                             cl->p_buffer_read++;
 361                             break;
 362                         default:
 363                             cl->i_tel_cmd = 0;
 364                             cl->p_buffer_read--;
 365                             break;
 366                         }
 367                         break;
 368                     case 2:
 369                         cl->i_tel_cmd = 0;
 370                         cl->p_buffer_read -= 2;
 371                         break;
 372                     }
 373
 374                     if( end ) break;
 375                 }
 376
 377                 if( (cl->p_buffer_read - cl->buffer_read) == 999 )
 378                 {
 379                     Write_message( cl, NULL, "Line too long\r\n",
 380                                    cl->i_mode + 2 );
 381                 }
 382
 383 #ifdef WIN32
 384                 if( i_recv <= 0 && WSAGetLastError() == WSAEWOULDBLOCK )
 385                 {
 386                     errno = EAGAIN;
 387                 }
 388 #endif
 389                 if( i_recv == 0 || ( i_recv == -1 && ( end || errno != EAGAIN ) ) )
 390                     goto drop;
 391             }
 392         }
 393
 394         /* and now we should bidouille the data we received / send */
 395         for(int i = 0 ; i < p_sys->i_clients ; i++ )
 396         {
 397             telnet_client_t *cl = p_sys->clients[i];
 398
 399             if( cl->i_mode >= WRITE_MODE_PWD && cl->i_buffer_write == 0 )
 400             {
 401                // we have finished to send
 402                cl->i_mode -= 2; // corresponding READ MODE
 403             }
 404             else if( cl->i_mode == READ_MODE_PWD &&
 405                      *cl->p_buffer_read == '\n' )
 406             {
 407                 *cl->p_buffer_read = '\0';
 408                 if( !psz_password || !strcmp( psz_password, cl->buffer_read ) )
 409                 {
 410                     Write_message( cl, NULL, "\xff\xfc\x01\r\nWelcome, "
 411                                    "Master\r\n> ", WRITE_MODE_CMD );
 412                 }
 413                 else
 414                 {
 415                     /* wrong password */
 416                     Write_message( cl, NULL,
 417                                    "\r\nWrong password.\r\nPassword: ",
 418                                    WRITE_MODE_PWD );
 419                 }
 420             }
 421             else if( cl->i_mode == READ_MODE_CMD &&
 422                      *cl->p_buffer_read == '\n' )
 423             {
 424                 /* ok, here is a command line */
 425                 if( !strncmp( cl->buffer_read, "logout", 6 ) ||
 426                     !strncmp( cl->buffer_read, "quit", 4 )  ||
 427                     !strncmp( cl->buffer_read, "exit", 4 ) )
 428                 {
 429                     net_Close( cl->fd );
 430                     TAB_REMOVE( p_intf->p_sys->i_clients ,
 431                                 p_intf->p_sys->clients , cl );
 432                     free( cl->buffer_write );
 433                     free( cl );
 434                 }
 435                 else if( !strncmp( cl->buffer_read, "shutdown", 8 ) )
 436                 {
 437                     msg_Err( p_intf, "shutdown requested" );
 438                     libvlc_Quit( p_intf->p_libvlc );
 439                 }
 440                 else if( *cl->buffer_read == '@'
 441                           && strchr( cl->buffer_read, ' ' ) )
 442                 {
 443                     /* Module specific commands (use same syntax as in the
 444                      * rc interface) */
 445                     char *psz_name = cl->buffer_read + 1;
 446                     char *psz_cmd, *psz_arg, *psz_msg;
 447                     int i_ret;
 448
 449                     psz_cmd = strchr( cl->buffer_read, ' ' );
 450                     *psz_cmd = '\0';  psz_cmd++;
 451                     if( ( psz_arg = strchr( psz_cmd, '\n' ) ) ) *psz_arg = '\0';
 452                     if( ( psz_arg = strchr( psz_cmd, '\r' ) ) ) *psz_arg = '\0';
 453                     if( ( psz_arg = strchr( psz_cmd, ' ' ) )
 454                         && *psz_arg )
 455                     {
 456                         *psz_arg = '\0';
 457                         psz_arg++;
 458                     }
 459
 460                     i_ret = var_Command( p_intf, psz_name, psz_cmd, psz_arg,
 461                                          &psz_msg );
 462
 463                     if( psz_msg )
 464                     {
 465                         vlm_message_t *message;
 466                         message = vlm_MessageNew( "Module command", "%s", psz_msg );
 467                         Write_message( cl, message, NULL, WRITE_MODE_CMD );
 468                         vlm_MessageDelete( message );
 469                         free( psz_msg );
 470                     }
 471                 }
 472                 else
 473                 {
 474                     vlm_message_t *message;
 475
 476                     /* create a standard string */
 477                     *cl->p_buffer_read = '\0';
 478
 479                     vlm_ExecuteCommand( p_sys->mediatheque, cl->buffer_read,
 480                                         &message );
 481                     if( !strncmp( cl->buffer_read, "help", 4 ) )
 482                     {
 483                         vlm_message_t *p_my_help =
 484                             vlm_MessageSimpleNew( "Telnet Specific Commands:" );
 485                         vlm_MessageAdd( p_my_help,
 486                             vlm_MessageSimpleNew( "logout, quit, exit" ) );
 487                         vlm_MessageAdd( p_my_help,
 488                             vlm_MessageSimpleNew( "shutdown" ) );
 489                         vlm_MessageAdd( p_my_help,
 490                             vlm_MessageSimpleNew( "@moduleinstance command argument" ) );
 491                         vlm_MessageAdd( message, p_my_help );
 492                     }
 493                     Write_message( cl, message, NULL, WRITE_MODE_CMD );
 494                     vlm_MessageDelete( message );
 495                 }
 496             }
 497         }
 498
 499         /* handle new connections */
 500         for (unsigned i = 0; i < nlisten; i++)
 501         {
 502             int fd;
 503
 504             if (ufd[ncli + i].revents == 0)
 505                 continue;
 506
 507             fd = net_AcceptSingle (VLC_OBJECT(p_intf), ufd[ncli + i].fd);
 508             if (fd == -1)
 509                 continue;
 510
 511             telnet_client_t *cl = calloc( 1, sizeof( telnet_client_t ));
 512             if (cl == NULL)
 513             {
 514                 net_Close (fd);
 515                 continue;
 516             }
 517
 518             cl->i_tel_cmd = 0;
 519             cl->fd = fd;
 520             cl->buffer_write = NULL;
 521             cl->p_buffer_write = cl->buffer_write;
 522             Write_message( cl, NULL,
 523                            "Password: \xff\xfb\x01" , WRITE_MODE_PWD );
 524             TAB_APPEND( p_sys->i_clients, p_sys->clients, cl );
 525         }
 526         vlc_restorecancel( canc );
 527     }
 528     vlc_cleanup_run ();
 529 }
 530
 531 static void Write_message( telnet_client_t *client, vlm_message_t *message,
 532                            const char *string_message, int i_mode )
 533 {
 534     char *psz_message;
 535
 536     client->p_buffer_read = client->buffer_read;
 537     (client->p_buffer_read)[0] = 0; // if (cl->p_buffer_read)[0] = '\n'
 538     free( client->buffer_write );
 539
 540     /* generate the psz_message string */
 541     if( message )
 542     {
 543         /* ok, look for vlm_message_t */
 544         psz_message = MessageToString( message, 0 );
 545     }
 546     else
 547     {
 548         /* it is a basic string_message */
 549         psz_message = strdup( string_message );
 550     }
 551
 552     client->buffer_write = client->p_buffer_write = psz_message;
 553     client->i_buffer_write = strlen( psz_message );
 554     client->i_mode = i_mode;
 555 }
 556
 557 /* We need the level of the message to put a beautiful indentation.
 558  * first level is 0 */
 559 static char *MessageToString( vlm_message_t *message, int i_level )
 560 {
 561 #define STRING_CR "\r\n"
 562 #define STRING_TAIL "> "
 563
 564     char *psz_message;
 565     int i, i_message = sizeof( STRING_TAIL );
 566
 567     if( !message || !message->psz_name )
 568     {
 569         return strdup( STRING_CR STRING_TAIL );
 570     }
 571     else if( !i_level && !message->i_child && !message->psz_value  )
 572     {
 573         /* A command is successful. Don't write anything */
 574         return strdup( /*STRING_CR*/ STRING_TAIL );
 575     }
 576
 577     i_message += strlen( message->psz_name ) + i_level * sizeof( "    " ) + 1;
 578     psz_message = malloc( i_message );
 579     assert( psz_message );
 580     *psz_message = 0;
 581     for( i = 0; i < i_level; i++ ) strcat( psz_message, "    " );
 582     strcat( psz_message, message->psz_name );
 583
 584     if( message->psz_value )
 585     {
 586         i_message += sizeof( " : " ) + strlen( message->psz_value ) +
 587             sizeof( STRING_CR );
 588         psz_message = realloc_or_free( psz_message, i_message );
 589         assert( psz_message );
 590         strcat( psz_message, " : " );
 591         strcat( psz_message, message->psz_value );
 592         strcat( psz_message, STRING_CR );
 593     }
 594     else
 595     {
 596         i_message += sizeof( STRING_CR );
 597         psz_message = realloc_or_free( psz_message, i_message );
 598         assert( psz_message );
 599         strcat( psz_message, STRING_CR );
 600     }
 601
 602     for( i = 0; i < message->i_child; i++ )
 603     {
 604         char *child_message =
 605             MessageToString( message->child[i], i_level + 1 );
 606
 607         i_message += strlen( child_message );
 608         psz_message = realloc_or_free( psz_message, i_message );
 609         assert( psz_message );
 610         strcat( psz_message, child_message );
 611         free( child_message );
 612     }
 613
 614     if( i_level == 0 ) strcat( psz_message, STRING_TAIL );
 615
 616     return psz_message;
 617 }