git.sesse.net Git - vlc/blob - modules/access/dvd/dvd.c

   1 /*****************************************************************************
   2  * dvd.c : DVD input module for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2000-2001 VideoLAN
   5  * $Id: dvd.c,v 1.3 2002/08/26 09:12:46 sam Exp $
   6  *
   7  * Authors: Samuel Hocevar <sam@zoy.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <stdlib.h>                                      /* malloc(), free() */
  28 #include <string.h>                                              /* strdup() */
  29
  30 #include <vlc/vlc.h>
  31
  32 #ifdef GOD_DAMN_DMCA
  33 #   include <stdio.h>
  34 #   include <fcntl.h>
  35 #   include <unistd.h>
  36 #   include <sys/types.h>
  37 #   include <sys/stat.h>
  38 #   include <sys/uio.h>                                      /* struct iovec */
  39 #   include <sys/ioctl.h>
  40 #   include <dlfcn.h>
  41 #   include <netinet/in.h>
  42 #   include <linux/cdrom.h>
  43
  44 #   include "dvdcss.h"
  45 #endif
  46
  47 /*****************************************************************************
  48  * Local prototypes.
  49  *****************************************************************************/
  50 int  E_(DVDOpen)   ( vlc_object_t * );
  51 void E_(DVDClose)  ( vlc_object_t * );
  52
  53 int  E_(DVDInit)   ( vlc_object_t * );
  54 void E_(DVDEnd)    ( vlc_object_t * );
  55
  56 #ifdef GOD_DAMN_DMCA
  57 static void *p_libdvdcss;
  58 static void ProbeLibDVDCSS  ( void );
  59 static void UnprobeLibDVDCSS( void );
  60 #endif
  61
  62 /*****************************************************************************
  63  * Module descriptor
  64  *****************************************************************************/
  65 #define CSSMETHOD_TEXT N_("method to use by libdvdcss for key decryption")
  66 #define CSSMETHOD_LONGTEXT N_( \
  67     "Set the method used by libdvdcss for key decryption.\n" \
  68     "title: decrypted title key is guessed from the encrypted sectors of " \
  69            "the stream. Thus it should work with a file as well as the " \
  70            "DVD device. But it sometimes takes much time to decrypt a title " \
  71            "key and may even fail. With this method, the key is only checked "\
  72            "at the beginning of each title, so it won't work if the key " \
  73            "changes in the middle of a title.\n" \
  74     "disc: the disc key is first cracked, then all title keys can be " \
  75            "decrypted instantly, which allows us to check them often.\n" \
  76     "key: the same as \"disc\" if you don't have a file with player keys " \
  77            "at compilation time. If you do, the decryption of the disc key " \
  78            "will be faster with this method. It is the one that was used by " \
  79            "libcss.\n" \
  80     "The default method is: key.")
  81
  82 static char *cssmethod_list[] = { "title", "disc", "key", NULL };
  83
  84 vlc_module_begin();
  85     int i;
  86     add_category_hint( N_("[dvd:][device][@raw_device][@[title][,[chapter][,angle]]]"), NULL );
  87     add_string_from_list( "dvd-css-method", NULL, cssmethod_list, NULL,
  88                           CSSMETHOD_TEXT, CSSMETHOD_LONGTEXT );
  89 #ifdef GOD_DAMN_DMCA
  90     set_description( _("DVD input module, uses libdvdcss if installed") );
  91     i = 90;
  92 #else
  93     set_description( _("DVD input module, uses libdvdcss") );
  94     i = 100;
  95 #endif
  96     add_shortcut( "dvdold" );
  97     add_submodule();
  98         set_capability( "access", i );
  99         set_callbacks( E_(DVDOpen), E_(DVDClose) );
 100     add_submodule();
 101         set_capability( "demux", 0 );
 102         set_callbacks( E_(DVDInit), E_(DVDEnd) );
 103 #ifdef GOD_DAMN_DMCA
 104     ProbeLibDVDCSS();
 105 #endif
 106 vlc_module_end();
 107
 108 #if 0 /* FIXME */
 109     UnprobeLibDVDCSS();
 110 #endif
 111
 112 /* Following functions are local */
 113
 114 #ifdef GOD_DAMN_DMCA
 115 /*****************************************************************************
 116  * ProbeLibDVDCSS: look for a libdvdcss object.
 117  *****************************************************************************
 118  * This functions looks for libdvdcss, using dlopen(), and fills function
 119  * pointers with what it finds. On failure, uses the dummy libdvdcss
 120  * replacement provided by vlc.
 121  *****************************************************************************/
 122 static void ProbeLibDVDCSS( void )
 123 {
 124     static char *pp_filelist[] = { "libdvdcss.so.2",
 125                                    "./libdvdcss.so.2",
 126                                    "./lib/libdvdcss.so.2",
 127                                    "libdvdcss.so.1",
 128                                    "./libdvdcss.so.1",
 129                                    "./lib/libdvdcss.so.1",
 130                                    NULL };
 131     char **pp_file = pp_filelist;
 132
 133     /* Try to open the dynamic object */
 134     do
 135     {
 136         p_libdvdcss = dlopen( *pp_file, RTLD_LAZY );
 137         if( p_libdvdcss != NULL )
 138         {
 139 //X            intf_WarnMsg( 2, "module: builtin module `dvd' found libdvdcss "
 140 //X                             "in `%s'", *pp_file );
 141             break;
 142         }
 143         pp_file++;
 144
 145     } while( *pp_file != NULL );
 146
 147     /* If libdvdcss.so was found, check that it's valid */
 148     if( p_libdvdcss == NULL )
 149     {
 150 //X        intf_ErrMsg( "dvd warning: libdvdcss.so.2 not present" );
 151     }
 152     else
 153     {
 154         ____dvdcss_open = dlsym( p_libdvdcss, "dvdcss_open" );
 155         ____dvdcss_close = dlsym( p_libdvdcss, "dvdcss_close" );
 156         ____dvdcss_title = dlsym( p_libdvdcss, "dvdcss_title" );
 157         ____dvdcss_seek = dlsym( p_libdvdcss, "dvdcss_seek" );
 158         ____dvdcss_read = dlsym( p_libdvdcss, "dvdcss_read" );
 159         ____dvdcss_readv = dlsym( p_libdvdcss, "dvdcss_readv" );
 160         ____dvdcss_error = dlsym( p_libdvdcss, "dvdcss_error" );
 161
 162         if( ____dvdcss_open == NULL || ____dvdcss_close == NULL
 163              || ____dvdcss_title == NULL || ____dvdcss_seek == NULL
 164              || ____dvdcss_read == NULL || ____dvdcss_readv == NULL
 165              || ____dvdcss_error == NULL )
 166         {
 167 //X            intf_ErrMsg( "dvd warning: missing symbols in libdvdcss.so.2, "
 168 //X                         "this shouldn't happen !" );
 169             dlclose( p_libdvdcss );
 170             p_libdvdcss = NULL;
 171         }
 172     }
 173
 174     /* If libdvdcss was not found or was not valid, use the dummy
 175      * replacement functions. */
 176     if( p_libdvdcss == NULL )
 177     {
 178 //X        intf_ErrMsg( "dvd warning: no valid libdvdcss found, "
 179 //X                     "I will only play unencrypted DVDs" );
 180 //X        intf_ErrMsg( "dvd warning: get libdvdcss at "
 181 //X                     "http://www.videolan.org/libdvdcss/" );
 182
 183         ____dvdcss_open = dummy_dvdcss_open;
 184         ____dvdcss_close = dummy_dvdcss_close;
 185         ____dvdcss_title = dummy_dvdcss_title;
 186         ____dvdcss_seek = dummy_dvdcss_seek;
 187         ____dvdcss_read = dummy_dvdcss_read;
 188         ____dvdcss_readv = dummy_dvdcss_readv;
 189         ____dvdcss_error = dummy_dvdcss_error;
 190     }
 191 }
 192
 193 /*****************************************************************************
 194  * UnprobeLibDVDCSS: free resources allocated by ProbeLibDVDCSS, if any.
 195  *****************************************************************************/
 196 static void UnprobeLibDVDCSS( void )
 197 {
 198     if( p_libdvdcss != NULL )
 199     {
 200         dlclose( p_libdvdcss );
 201         p_libdvdcss = NULL;
 202     }
 203 }
 204
 205 /* Dummy libdvdcss with minimal DVD access. */
 206
 207 /*****************************************************************************
 208  * Local structure
 209  *****************************************************************************/
 210 struct dvdcss_s
 211 {
 212     /* File descriptor */
 213     int i_fd;
 214 };
 215
 216 /*****************************************************************************
 217  * dvdcss_open: initialize library, open a DVD device, crack CSS key
 218  *****************************************************************************/
 219 extern dvdcss_handle dummy_dvdcss_open ( char *psz_target )
 220 {
 221     dvdcss_handle dvdcss;
 222     dvd_struct    dvd;
 223
 224     /* Allocate the library structure */
 225     dvdcss = malloc( sizeof( struct dvdcss_s ) );
 226     if( dvdcss == NULL )
 227     {
 228         fprintf( stderr, "dvd error: "
 229                          "dummy libdvdcss could not allocate memory\n" );
 230         return NULL;
 231     }
 232
 233     /* Open the device */
 234     dvdcss->i_fd = open( psz_target, 0 );
 235     if( dvdcss->i_fd < 0 )
 236     {
 237         fprintf( stderr, "dvd error: "
 238                          "dummy libdvdcss could not open device\n" );
 239         free( dvdcss );
 240         return NULL;
 241     }
 242
 243     /* Check for encryption or ioctl failure */
 244     dvd.type = DVD_STRUCT_COPYRIGHT;
 245     dvd.copyright.layer_num = 0;
 246     if( ioctl( dvdcss->i_fd, DVD_READ_STRUCT, &dvd ) != 0
 247          || dvd.copyright.cpst )
 248     {
 249         fprintf( stderr, "dvd error: "
 250                          "dummy libdvdcss could not decrypt disc\n" );
 251         close( dvdcss->i_fd );
 252         free( dvdcss );
 253         return NULL;
 254     }
 255
 256     return dvdcss;
 257 }
 258
 259 /*****************************************************************************
 260  * dvdcss_error: return the last libdvdcss error message
 261  *****************************************************************************/
 262 extern char * dummy_dvdcss_error ( dvdcss_handle dvdcss )
 263 {
 264     return "generic error";
 265 }
 266
 267 /*****************************************************************************
 268  * dvdcss_seek: seek into the device
 269  *****************************************************************************/
 270 extern int dummy_dvdcss_seek ( dvdcss_handle dvdcss, int i_blocks,
 271                                                      int i_flags )
 272 {
 273     off_t i_read;
 274
 275     i_read = lseek( dvdcss->i_fd,
 276                     (off_t)i_blocks * (off_t)DVDCSS_BLOCK_SIZE, SEEK_SET );
 277
 278     return i_read / DVDCSS_BLOCK_SIZE;
 279 }
 280
 281 /*****************************************************************************
 282  * dvdcss_title: crack the current title key if needed
 283  *****************************************************************************/
 284 extern int dummy_dvdcss_title ( dvdcss_handle dvdcss, int i_block )
 285 {
 286     return 0;
 287 }
 288
 289 /*****************************************************************************
 290  * dvdcss_read: read data from the device, decrypt if requested
 291  *****************************************************************************/
 292 extern int dummy_dvdcss_read ( dvdcss_handle dvdcss, void *p_buffer,
 293                                                      int i_blocks,
 294                                                      int i_flags )
 295 {
 296     int i_bytes;
 297
 298     i_bytes = read( dvdcss->i_fd, p_buffer,
 299                     (size_t)i_blocks * DVDCSS_BLOCK_SIZE );
 300
 301     return i_bytes / DVDCSS_BLOCK_SIZE;
 302 }
 303
 304 /*****************************************************************************
 305  * dvdcss_readv: read data to an iovec structure, decrypt if reaquested
 306  *****************************************************************************/
 307 extern int dummy_dvdcss_readv ( dvdcss_handle dvdcss, void *p_iovec,
 308                                                       int i_blocks,
 309                                                       int i_flags )
 310 {
 311     int i_read;
 312
 313     i_read = readv( dvdcss->i_fd, (struct iovec*)p_iovec, i_blocks );
 314
 315     return i_read / DVDCSS_BLOCK_SIZE;
 316 }
 317
 318 /*****************************************************************************
 319  * dvdcss_close: close the DVD device and clean up the library
 320  *****************************************************************************/
 321 extern int dummy_dvdcss_close ( dvdcss_handle dvdcss )
 322 {
 323     int i_ret;
 324
 325     i_ret = close( dvdcss->i_fd );
 326
 327     if( i_ret < 0 )
 328     {
 329         return i_ret;
 330     }
 331
 332     free( dvdcss );
 333
 334     return 0;
 335 }
 336
 337 #endif
 338