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 1.7 2003/05/15 22:27:36 massiot 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_usage_hint( N_("[dvd:][device][@raw_device][@[title][,[chapter][,angle]]]") );
  87     add_category_hint( N_("dvd"), NULL, VLC_TRUE );
  88     add_string_from_list( "dvdcss-method", NULL, cssmethod_list, NULL,
  89                           CSSMETHOD_TEXT, CSSMETHOD_LONGTEXT, VLC_TRUE );
  90 #ifdef GOD_DAMN_DMCA
  91     set_description( _("DVD input (uses libdvdcss if installed)") );
  92     i = 90;
  93 #else
  94     set_description( _("DVD input (uses libdvdcss)") );
  95     i = 100;
  96 #endif
  97     add_shortcut( "dvdold" );
  98     add_shortcut( "dvdsimple" );
  99     add_submodule();
 100         set_capability( "access", i );
 101         set_callbacks( E_(DVDOpen), E_(DVDClose) );
 102     add_submodule();
 103         set_capability( "demux", 0 );
 104         set_callbacks( E_(DVDInit), E_(DVDEnd) );
 105 #ifdef GOD_DAMN_DMCA
 106     ProbeLibDVDCSS();
 107 #endif
 108 vlc_module_end();
 109
 110 #if 0 /* FIXME */
 111     UnprobeLibDVDCSS();
 112 #endif
 113
 114 /* Following functions are local */
 115
 116 #ifdef GOD_DAMN_DMCA
 117 /*****************************************************************************
 118  * ProbeLibDVDCSS: look for a libdvdcss object.
 119  *****************************************************************************
 120  * This functions looks for libdvdcss, using dlopen(), and fills function
 121  * pointers with what it finds. On failure, uses the dummy libdvdcss
 122  * replacement provided by vlc.
 123  *****************************************************************************/
 124 static void ProbeLibDVDCSS( void )
 125 {
 126     static char *pp_filelist[] = { "libdvdcss.so.2",
 127                                    "./libdvdcss.so.2",
 128                                    "./lib/libdvdcss.so.2",
 129                                    "libdvdcss.so.1",
 130                                    "./libdvdcss.so.1",
 131                                    "./lib/libdvdcss.so.1",
 132                                    NULL };
 133     char **pp_file = pp_filelist;
 134
 135     /* Try to open the dynamic object */
 136     do
 137     {
 138         p_libdvdcss = dlopen( *pp_file, RTLD_LAZY );
 139         if( p_libdvdcss != NULL )
 140         {
 141 //X            intf_WarnMsg( 2, "module: builtin module `dvd' found libdvdcss "
 142 //X                             "in `%s'", *pp_file );
 143             break;
 144         }
 145         pp_file++;
 146
 147     } while( *pp_file != NULL );
 148
 149     /* If libdvdcss.so was found, check that it's valid */
 150     if( p_libdvdcss == NULL )
 151     {
 152 //X        intf_ErrMsg( "dvd warning: libdvdcss.so.2 not present" );
 153     }
 154     else
 155     {
 156         ____dvdcss_open = dlsym( p_libdvdcss, "dvdcss_open" );
 157         ____dvdcss_close = dlsym( p_libdvdcss, "dvdcss_close" );
 158         ____dvdcss_title = dlsym( p_libdvdcss, "dvdcss_title" );
 159         ____dvdcss_seek = dlsym( p_libdvdcss, "dvdcss_seek" );
 160         ____dvdcss_read = dlsym( p_libdvdcss, "dvdcss_read" );
 161         ____dvdcss_readv = dlsym( p_libdvdcss, "dvdcss_readv" );
 162         ____dvdcss_error = dlsym( p_libdvdcss, "dvdcss_error" );
 163
 164         if( ____dvdcss_open == NULL || ____dvdcss_close == NULL
 165              || ____dvdcss_title == NULL || ____dvdcss_seek == NULL
 166              || ____dvdcss_read == NULL || ____dvdcss_readv == NULL
 167              || ____dvdcss_error == NULL )
 168         {
 169 //X            intf_ErrMsg( "dvd warning: missing symbols in libdvdcss.so.2, "
 170 //X                         "this shouldn't happen !" );
 171             dlclose( p_libdvdcss );
 172             p_libdvdcss = NULL;
 173         }
 174     }
 175
 176     /* If libdvdcss was not found or was not valid, use the dummy
 177      * replacement functions. */
 178     if( p_libdvdcss == NULL )
 179     {
 180 //X        intf_ErrMsg( "dvd warning: no valid libdvdcss found, "
 181 //X                     "I will only play unencrypted DVDs" );
 182 //X        intf_ErrMsg( "dvd warning: get libdvdcss at "
 183 //X                     "http://www.videolan.org/libdvdcss/" );
 184
 185         ____dvdcss_open = dummy_dvdcss_open;
 186         ____dvdcss_close = dummy_dvdcss_close;
 187         ____dvdcss_title = dummy_dvdcss_title;
 188         ____dvdcss_seek = dummy_dvdcss_seek;
 189         ____dvdcss_read = dummy_dvdcss_read;
 190         ____dvdcss_readv = dummy_dvdcss_readv;
 191         ____dvdcss_error = dummy_dvdcss_error;
 192     }
 193 }
 194
 195 /*****************************************************************************
 196  * UnprobeLibDVDCSS: free resources allocated by ProbeLibDVDCSS, if any.
 197  *****************************************************************************/
 198 static void UnprobeLibDVDCSS( void )
 199 {
 200     if( p_libdvdcss != NULL )
 201     {
 202         dlclose( p_libdvdcss );
 203         p_libdvdcss = NULL;
 204     }
 205 }
 206
 207 /* Dummy libdvdcss with minimal DVD access. */
 208
 209 /*****************************************************************************
 210  * Local structure
 211  *****************************************************************************/
 212 struct dvdcss_s
 213 {
 214     /* File descriptor */
 215     int i_fd;
 216 };
 217
 218 /*****************************************************************************
 219  * dvdcss_open: initialize library, open a DVD device, crack CSS key
 220  *****************************************************************************/
 221 extern dvdcss_handle dummy_dvdcss_open ( char *psz_target )
 222 {
 223     dvdcss_handle dvdcss;
 224     dvd_struct    dvd;
 225
 226     /* Allocate the library structure */
 227     dvdcss = malloc( sizeof( struct dvdcss_s ) );
 228     if( dvdcss == NULL )
 229     {
 230         fprintf( stderr, "dvd error: "
 231                          "dummy libdvdcss could not allocate memory\n" );
 232         return NULL;
 233     }
 234
 235     /* Open the device */
 236     dvdcss->i_fd = open( psz_target, 0 );
 237     if( dvdcss->i_fd < 0 )
 238     {
 239         fprintf( stderr, "dvd error: "
 240                          "dummy libdvdcss could not open device\n" );
 241         free( dvdcss );
 242         return NULL;
 243     }
 244
 245     /* Check for encryption or ioctl failure */
 246     dvd.type = DVD_STRUCT_COPYRIGHT;
 247     dvd.copyright.layer_num = 0;
 248     if( ioctl( dvdcss->i_fd, DVD_READ_STRUCT, &dvd ) != 0
 249          || dvd.copyright.cpst )
 250     {
 251         fprintf( stderr, "dvd error: "
 252                          "dummy libdvdcss could not decrypt disc\n" );
 253         close( dvdcss->i_fd );
 254         free( dvdcss );
 255         return NULL;
 256     }
 257
 258     return dvdcss;
 259 }
 260
 261 /*****************************************************************************
 262  * dvdcss_error: return the last libdvdcss error message
 263  *****************************************************************************/
 264 extern char * dummy_dvdcss_error ( dvdcss_handle dvdcss )
 265 {
 266     return "generic error";
 267 }
 268
 269 /*****************************************************************************
 270  * dvdcss_seek: seek into the device
 271  *****************************************************************************/
 272 extern int dummy_dvdcss_seek ( dvdcss_handle dvdcss, int i_blocks,
 273                                                      int i_flags )
 274 {
 275     off_t i_read;
 276
 277     i_read = lseek( dvdcss->i_fd,
 278                     (off_t)i_blocks * (off_t)DVDCSS_BLOCK_SIZE, SEEK_SET );
 279
 280     return i_read / DVDCSS_BLOCK_SIZE;
 281 }
 282
 283 /*****************************************************************************
 284  * dvdcss_title: crack the current title key if needed
 285  *****************************************************************************/
 286 extern int dummy_dvdcss_title ( dvdcss_handle dvdcss, int i_block )
 287 {
 288     return 0;
 289 }
 290
 291 /*****************************************************************************
 292  * dvdcss_read: read data from the device, decrypt if requested
 293  *****************************************************************************/
 294 extern int dummy_dvdcss_read ( dvdcss_handle dvdcss, void *p_buffer,
 295                                                      int i_blocks,
 296                                                      int i_flags )
 297 {
 298     int i_bytes;
 299
 300     i_bytes = read( dvdcss->i_fd, p_buffer,
 301                     (size_t)i_blocks * DVDCSS_BLOCK_SIZE );
 302
 303     return i_bytes / DVDCSS_BLOCK_SIZE;
 304 }
 305
 306 /*****************************************************************************
 307  * dvdcss_readv: read data to an iovec structure, decrypt if reaquested
 308  *****************************************************************************/
 309 extern int dummy_dvdcss_readv ( dvdcss_handle dvdcss, void *p_iovec,
 310                                                       int i_blocks,
 311                                                       int i_flags )
 312 {
 313     int i_read;
 314
 315     i_read = readv( dvdcss->i_fd, (struct iovec*)p_iovec, i_blocks );
 316
 317     return i_read / DVDCSS_BLOCK_SIZE;
 318 }
 319
 320 /*****************************************************************************
 321  * dvdcss_close: close the DVD device and clean up the library
 322  *****************************************************************************/
 323 extern int dummy_dvdcss_close ( dvdcss_handle dvdcss )
 324 {
 325     int i_ret;
 326
 327     i_ret = close( dvdcss->i_fd );
 328
 329     if( i_ret < 0 )
 330     {
 331         return i_ret;
 332     }
 333
 334     free( dvdcss );
 335
 336     return 0;
 337 }
 338
 339 #endif
 340