mirror of https://github.com/mpv-player/mpv
815 lines
25 KiB
C
815 lines
25 KiB
C
/* libdvdcss.c: DVD reading library.
|
|
*
|
|
* Authors: Stéphane Borel <stef@via.ecp.fr>
|
|
* Sam Hocevar <sam@zoy.org>
|
|
* Håkan Hjort <d95hjort@dtek.chalmers.se>
|
|
*
|
|
* Copyright (C) 1998-2008 VideoLAN
|
|
* $Id$
|
|
*
|
|
* This library is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this library; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
/**
|
|
* \mainpage libdvdcss developer documentation
|
|
*
|
|
* \section intro Introduction
|
|
*
|
|
* \e libdvdcss is a simple library designed for accessing DVDs like a block
|
|
* device without having to bother about the decryption. The important features
|
|
* are:
|
|
* \li portability: currently supported platforms are GNU/Linux, FreeBSD,
|
|
* NetBSD, OpenBSD, BSD/OS, BeOS, Windows 95/98, Windows NT/2000, MacOS X,
|
|
* Solaris, HP-UX and OS/2.
|
|
* \li adaptability: unlike most similar projects, libdvdcss doesn't require
|
|
* the region of your drive to be set and will try its best to read from
|
|
* the disc even in the case of a region mismatch.
|
|
* \li simplicity: a DVD player can be built around the \e libdvdcss API using
|
|
* no more than 4 or 5 library calls.
|
|
*
|
|
* \e libdvdcss is free software, released under the General Public License.
|
|
* This ensures that \e libdvdcss remains free and used only with free
|
|
* software.
|
|
*
|
|
* \section api The libdvdcss API
|
|
*
|
|
* The complete \e libdvdcss programming interface is documented in the
|
|
* dvdcss.h file.
|
|
*
|
|
* \section env Environment variables
|
|
*
|
|
* Some environment variables can be used to change the behaviour of
|
|
* \e libdvdcss without having to modify the program which uses it. These
|
|
* variables are:
|
|
*
|
|
* \li \b DVDCSS_VERBOSE: sets the verbosity level.
|
|
* - \c 0 outputs no messages at all.
|
|
* - \c 1 outputs error messages to stderr.
|
|
* - \c 2 outputs error messages and debug messages to stderr.
|
|
*
|
|
* \li \b DVDCSS_METHOD: sets the authentication and decryption method
|
|
* that \e libdvdcss will use to read scrambled discs. Can be one
|
|
* of \c title, \c key or \c disc.
|
|
* - \c key is the default method. \e libdvdcss will use a set of
|
|
* calculated player keys to try and get the disc key. This can fail
|
|
* if the drive does not recognize any of the player keys.
|
|
* - \c disc is a fallback method when \c key has failed. Instead of
|
|
* using player keys, \e libdvdcss will crack the disc key using
|
|
* a brute force algorithm. This process is CPU intensive and requires
|
|
* 64 MB of memory to store temporary data.
|
|
* - \c title is the fallback when all other methods have failed. It does
|
|
* not rely on a key exchange with the DVD drive, but rather uses a
|
|
* crypto attack to guess the title key. On rare cases this may fail
|
|
* because there is not enough encrypted data on the disc to perform
|
|
* a statistical attack, but in the other hand it is the only way to
|
|
* decrypt a DVD stored on a hard disc, or a DVD with the wrong region
|
|
* on an RPC2 drive.
|
|
*
|
|
* \li \b DVDCSS_RAW_DEVICE: specify the raw device to use. Exact usage will
|
|
* depend on your operating system, the Linux utility to set up raw devices
|
|
* is \c raw(8) for instance. Please note that on most operating systems,
|
|
* using a raw device requires highly aligned buffers: Linux requires a
|
|
* 2048 bytes alignment (which is the size of a DVD sector).
|
|
*
|
|
* \li \b DVDCSS_CACHE: specify a directory in which to store title key
|
|
* values. This will speed up descrambling of DVDs which are in the
|
|
* cache. The DVDCSS_CACHE directory is created if it does not exist,
|
|
* and a subdirectory is created named after the DVD's title or
|
|
* manufacturing date. If DVDCSS_CACHE is not set or is empty, \e libdvdcss
|
|
* will use the default value which is "${HOME}/.dvdcss/" under Unix and
|
|
* "C:\Documents and Settings\$USER\Application Data\dvdcss\" under Win32.
|
|
* The special value "off" disables caching.
|
|
*/
|
|
|
|
/*
|
|
* Preamble
|
|
*/
|
|
#include "config.h"
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#ifdef HAVE_SYS_PARAM_H
|
|
# include <sys/param.h>
|
|
#endif
|
|
#ifdef HAVE_PWD_H
|
|
# include <pwd.h>
|
|
#endif
|
|
#include <fcntl.h>
|
|
#include <errno.h>
|
|
|
|
#ifdef HAVE_UNISTD_H
|
|
# include <unistd.h>
|
|
#endif
|
|
|
|
#ifdef HAVE_LIMITS_H
|
|
# include <limits.h>
|
|
#endif
|
|
|
|
#ifdef HAVE_DIRECT_H
|
|
# include <direct.h>
|
|
#endif
|
|
|
|
#include "dvdcss/dvdcss.h"
|
|
|
|
#include "common.h"
|
|
#include "css.h"
|
|
#include "libdvdcss.h"
|
|
#include "ioctl.h"
|
|
#include "device.h"
|
|
|
|
/**
|
|
* \brief Symbol for version checks.
|
|
*
|
|
* The name of this symbol contains the library major number, which makes it
|
|
* easy to check which \e libdvdcss development headers are installed on the
|
|
* system with tools such as autoconf.
|
|
*
|
|
* The variable itself contains the exact version number of the library,
|
|
* which can be useful for specific feature needs.
|
|
*/
|
|
char * dvdcss_interface_2 = VERSION;
|
|
|
|
/**
|
|
* \brief Open a DVD device or directory and return a dvdcss instance.
|
|
*
|
|
* \param psz_target a string containing the target name, for instance
|
|
* "/dev/hdc" or "E:".
|
|
* \return a handle to a dvdcss instance or NULL on error.
|
|
*
|
|
* Initialize the \e libdvdcss library and open the requested DVD device or
|
|
* directory. \e libdvdcss checks whether ioctls can be performed on the disc,
|
|
* and when possible, the disc key is retrieved.
|
|
*
|
|
* dvdcss_open() returns a handle to be used for all subsequent \e libdvdcss
|
|
* calls. If an error occurred, NULL is returned.
|
|
*/
|
|
LIBDVDCSS_EXPORT dvdcss_t dvdcss_open ( char *psz_target )
|
|
{
|
|
char psz_buffer[PATH_MAX];
|
|
int i_ret;
|
|
|
|
char *psz_method = getenv( "DVDCSS_METHOD" );
|
|
char *psz_verbose = getenv( "DVDCSS_VERBOSE" );
|
|
char *psz_cache = getenv( "DVDCSS_CACHE" );
|
|
#if !defined(WIN32) && !defined(SYS_OS2)
|
|
char *psz_raw_device = getenv( "DVDCSS_RAW_DEVICE" );
|
|
#endif
|
|
|
|
dvdcss_t dvdcss;
|
|
|
|
/*
|
|
* Allocate the library structure
|
|
*/
|
|
dvdcss = malloc( sizeof( struct dvdcss_s ) );
|
|
if( dvdcss == NULL )
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Initialize structure with default values
|
|
*/
|
|
#if !defined(WIN32) && !defined(SYS_OS2)
|
|
dvdcss->i_raw_fd = -1;
|
|
#endif
|
|
dvdcss->p_titles = NULL;
|
|
dvdcss->psz_device = (char *)strdup( psz_target );
|
|
dvdcss->psz_error = "no error";
|
|
dvdcss->i_method = DVDCSS_METHOD_KEY;
|
|
dvdcss->psz_cachefile[0] = '\0';
|
|
dvdcss->b_debug = 0;
|
|
dvdcss->b_errors = 0;
|
|
|
|
/*
|
|
* Find verbosity from DVDCSS_VERBOSE environment variable
|
|
*/
|
|
if( psz_verbose != NULL )
|
|
{
|
|
int i = atoi( psz_verbose );
|
|
|
|
if( i >= 2 ) dvdcss->b_debug = i;
|
|
if( i >= 1 ) dvdcss->b_errors = 1;
|
|
}
|
|
|
|
/*
|
|
* Find method from DVDCSS_METHOD environment variable
|
|
*/
|
|
if( psz_method != NULL )
|
|
{
|
|
if( !strncmp( psz_method, "key", 4 ) )
|
|
{
|
|
dvdcss->i_method = DVDCSS_METHOD_KEY;
|
|
}
|
|
else if( !strncmp( psz_method, "disc", 5 ) )
|
|
{
|
|
dvdcss->i_method = DVDCSS_METHOD_DISC;
|
|
}
|
|
else if( !strncmp( psz_method, "title", 5 ) )
|
|
{
|
|
dvdcss->i_method = DVDCSS_METHOD_TITLE;
|
|
}
|
|
else
|
|
{
|
|
print_error( dvdcss, "unknown decrypt method, please choose "
|
|
"from 'title', 'key' or 'disc'" );
|
|
free( dvdcss->psz_device );
|
|
free( dvdcss );
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If DVDCSS_CACHE was not set, try to guess a default value
|
|
*/
|
|
if( psz_cache == NULL || psz_cache[0] == '\0' )
|
|
{
|
|
#ifdef HAVE_DIRECT_H
|
|
typedef HRESULT( WINAPI *SHGETFOLDERPATH )
|
|
( HWND, int, HANDLE, DWORD, LPTSTR );
|
|
|
|
# define CSIDL_FLAG_CREATE 0x8000
|
|
# define CSIDL_APPDATA 0x1A
|
|
# define SHGFP_TYPE_CURRENT 0
|
|
|
|
char psz_home[MAX_PATH];
|
|
HINSTANCE p_dll;
|
|
SHGETFOLDERPATH p_getpath;
|
|
|
|
*psz_home = '\0';
|
|
|
|
/* Load the shfolder dll to retrieve SHGetFolderPath */
|
|
p_dll = LoadLibrary( "shfolder.dll" );
|
|
if( p_dll )
|
|
{
|
|
p_getpath = (void*)GetProcAddress( p_dll, "SHGetFolderPathA" );
|
|
if( p_getpath )
|
|
{
|
|
/* Get the "Application Data" folder for the current user */
|
|
if( p_getpath( NULL, CSIDL_APPDATA | CSIDL_FLAG_CREATE,
|
|
NULL, SHGFP_TYPE_CURRENT, psz_home ) == S_OK )
|
|
{
|
|
FreeLibrary( p_dll );
|
|
}
|
|
else
|
|
{
|
|
*psz_home = '\0';
|
|
}
|
|
}
|
|
FreeLibrary( p_dll );
|
|
}
|
|
|
|
/* Cache our keys in
|
|
* C:\Documents and Settings\$USER\Application Data\dvdcss\ */
|
|
if( *psz_home )
|
|
{
|
|
snprintf( psz_buffer, PATH_MAX, "%s/dvdcss", psz_home );
|
|
psz_buffer[PATH_MAX-1] = '\0';
|
|
psz_cache = psz_buffer;
|
|
}
|
|
#else
|
|
char *psz_home = NULL;
|
|
# ifdef HAVE_PWD_H
|
|
struct passwd *p_pwd;
|
|
|
|
/* Try looking in password file for home dir. */
|
|
p_pwd = getpwuid(getuid());
|
|
if( p_pwd )
|
|
{
|
|
psz_home = p_pwd->pw_dir;
|
|
}
|
|
# endif
|
|
|
|
if( psz_home == NULL )
|
|
{
|
|
psz_home = getenv( "HOME" );
|
|
}
|
|
if( psz_home == NULL )
|
|
{
|
|
psz_home = getenv( "USERPROFILE" );
|
|
}
|
|
|
|
/* Cache our keys in ${HOME}/.dvdcss/ */
|
|
if( psz_home )
|
|
{
|
|
int home_pos = 0;
|
|
|
|
#ifdef SYS_OS2
|
|
if( *psz_home == '/' || *psz_home == '\\')
|
|
{
|
|
char *psz_unixroot = getenv("UNIXROOT");
|
|
|
|
if( psz_unixroot &&
|
|
psz_unixroot[0] &&
|
|
psz_unixroot[1] == ':' &&
|
|
psz_unixroot[2] == '\0')
|
|
{
|
|
strcpy( psz_buffer, psz_unixroot );
|
|
home_pos = 2;
|
|
}
|
|
}
|
|
#endif
|
|
snprintf( psz_buffer + home_pos, PATH_MAX - home_pos,
|
|
"%s/.dvdcss", psz_home );
|
|
psz_buffer[PATH_MAX-1] = '\0';
|
|
psz_cache = psz_buffer;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Find cache dir from the DVDCSS_CACHE environment variable
|
|
*/
|
|
if( psz_cache != NULL )
|
|
{
|
|
if( psz_cache[0] == '\0' || !strcmp( psz_cache, "off" ) )
|
|
{
|
|
psz_cache = NULL;
|
|
}
|
|
/* Check that we can add the ID directory and the block filename */
|
|
else if( strlen( psz_cache ) + 1 + 32 + 1 + (KEY_SIZE * 2) + 10 + 1
|
|
> PATH_MAX )
|
|
{
|
|
print_error( dvdcss, "cache directory name is too long" );
|
|
psz_cache = NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Open device
|
|
*/
|
|
_dvdcss_check( dvdcss );
|
|
i_ret = _dvdcss_open( dvdcss );
|
|
if( i_ret < 0 )
|
|
{
|
|
free( dvdcss->psz_device );
|
|
free( dvdcss );
|
|
return NULL;
|
|
}
|
|
|
|
dvdcss->b_scrambled = 1; /* Assume the worst */
|
|
dvdcss->b_ioctls = _dvdcss_use_ioctls( dvdcss );
|
|
|
|
if( dvdcss->b_ioctls )
|
|
{
|
|
_dvdcss_test( dvdcss );
|
|
}
|
|
|
|
/* If disc is CSS protected and the ioctls work, authenticate the drive */
|
|
if( dvdcss->b_scrambled && dvdcss->b_ioctls )
|
|
{
|
|
i_ret = _dvdcss_disckey( dvdcss );
|
|
|
|
if( i_ret < 0 )
|
|
{
|
|
print_debug( dvdcss, "could not get disc key" );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
memset( dvdcss->css.p_disc_key, 0, KEY_SIZE );
|
|
}
|
|
|
|
/* If the cache is enabled, write the cache directory tag */
|
|
if( psz_cache )
|
|
{
|
|
char *psz_tag = "Signature: 8a477f597d28d172789f06886806bc55\r\n"
|
|
"# This file is a cache directory tag created by libdvdcss.\r\n"
|
|
"# For information about cache directory tags, see:\r\n"
|
|
"# http://www.brynosaurus.com/cachedir/\r\n";
|
|
char psz_tagfile[PATH_MAX + 1 + 12 + 1];
|
|
int i_fd;
|
|
|
|
sprintf( psz_tagfile, "%s/CACHEDIR.TAG", psz_cache );
|
|
i_fd = open( psz_tagfile, O_RDWR|O_CREAT, 0644 );
|
|
if( i_fd >= 0 )
|
|
{
|
|
write( i_fd, psz_tag, strlen(psz_tag) );
|
|
close( i_fd );
|
|
}
|
|
}
|
|
|
|
/* If the cache is enabled, extract a unique disc ID */
|
|
if( psz_cache )
|
|
{
|
|
uint8_t p_sector[DVDCSS_BLOCK_SIZE];
|
|
char psz_key[1 + KEY_SIZE * 2 + 1];
|
|
char *psz_title;
|
|
uint8_t *psz_serial;
|
|
int i;
|
|
|
|
/* We read sector 0. If it starts with 0x000001ba (BE), we are
|
|
* reading a VOB file, and we should not cache anything. */
|
|
|
|
i_ret = dvdcss->pf_seek( dvdcss, 0 );
|
|
if( i_ret != 0 )
|
|
{
|
|
goto nocache;
|
|
}
|
|
|
|
i_ret = dvdcss->pf_read( dvdcss, p_sector, 1 );
|
|
if( i_ret != 1 )
|
|
{
|
|
goto nocache;
|
|
}
|
|
|
|
if( p_sector[0] == 0x00 && p_sector[1] == 0x00
|
|
&& p_sector[2] == 0x01 && p_sector[3] == 0xba )
|
|
{
|
|
goto nocache;
|
|
}
|
|
|
|
/* The data we are looking for is at sector 16 (32768 bytes):
|
|
* - offset 40: disc title (32 uppercase chars)
|
|
* - offset 813: manufacturing date + serial no (16 digits) */
|
|
|
|
i_ret = dvdcss->pf_seek( dvdcss, 16 );
|
|
if( i_ret != 16 )
|
|
{
|
|
goto nocache;
|
|
}
|
|
|
|
i_ret = dvdcss->pf_read( dvdcss, p_sector, 1 );
|
|
if( i_ret != 1 )
|
|
{
|
|
goto nocache;
|
|
}
|
|
|
|
/* Get the disc title */
|
|
psz_title = (char *)p_sector + 40;
|
|
psz_title[32] = '\0';
|
|
|
|
for( i = 0 ; i < 32 ; i++ )
|
|
{
|
|
if( psz_title[i] <= ' ' )
|
|
{
|
|
psz_title[i] = '\0';
|
|
break;
|
|
}
|
|
else if( psz_title[i] == '/' || psz_title[i] == '\\' )
|
|
{
|
|
psz_title[i] = '-';
|
|
}
|
|
}
|
|
|
|
/* Get the date + serial */
|
|
psz_serial = p_sector + 813;
|
|
psz_serial[16] = '\0';
|
|
|
|
/* Check that all characters are digits, otherwise convert. */
|
|
for( i = 0 ; i < 16 ; i++ )
|
|
{
|
|
if( psz_serial[i] < '0' || psz_serial[i] > '9' )
|
|
{
|
|
char psz_tmp[16 + 1];
|
|
sprintf( psz_tmp,
|
|
"%.2x%.2x%.2x%.2x%.2x%.2x%.2x%.2x",
|
|
psz_serial[0], psz_serial[1], psz_serial[2],
|
|
psz_serial[3], psz_serial[4], psz_serial[5],
|
|
psz_serial[6], psz_serial[7] );
|
|
memcpy( psz_serial, psz_tmp, 16 );
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Get disk key, since some discs have got same title, manufacturing
|
|
* date and serial number, but different keys */
|
|
if( dvdcss->b_scrambled )
|
|
{
|
|
psz_key[0] = '-';
|
|
for( i = 0; i < KEY_SIZE; i++ )
|
|
{
|
|
sprintf( &psz_key[1+i*2], "%.2x", dvdcss->css.p_disc_key[i] );
|
|
}
|
|
psz_key[1 + KEY_SIZE * 2] = '\0';
|
|
}
|
|
else
|
|
{
|
|
psz_key[0] = 0;
|
|
}
|
|
|
|
/* We have a disc name or ID, we can create the cache dir */
|
|
i = sprintf( dvdcss->psz_cachefile, "%s", psz_cache );
|
|
#if !defined( WIN32 ) || defined( SYS_CYGWIN )
|
|
i_ret = mkdir( dvdcss->psz_cachefile, 0755 );
|
|
#else
|
|
i_ret = mkdir( dvdcss->psz_cachefile );
|
|
#endif
|
|
if( i_ret < 0 && errno != EEXIST )
|
|
{
|
|
print_error( dvdcss, "failed creating cache directory" );
|
|
dvdcss->psz_cachefile[0] = '\0';
|
|
goto nocache;
|
|
}
|
|
|
|
i += sprintf( dvdcss->psz_cachefile + i, "/%s-%s%s", psz_title,
|
|
psz_serial, psz_key );
|
|
#if !defined( WIN32 ) || defined( SYS_CYGWIN )
|
|
i_ret = mkdir( dvdcss->psz_cachefile, 0755 );
|
|
#else
|
|
i_ret = mkdir( dvdcss->psz_cachefile );
|
|
#endif
|
|
if( i_ret < 0 && errno != EEXIST )
|
|
{
|
|
print_error( dvdcss, "failed creating cache subdirectory" );
|
|
dvdcss->psz_cachefile[0] = '\0';
|
|
goto nocache;
|
|
}
|
|
i += sprintf( dvdcss->psz_cachefile + i, "/");
|
|
|
|
/* Pointer to the filename we will use. */
|
|
dvdcss->psz_block = dvdcss->psz_cachefile + i;
|
|
|
|
print_debug( dvdcss, "using CSS key cache dir: %s",
|
|
dvdcss->psz_cachefile );
|
|
}
|
|
nocache:
|
|
|
|
#if !defined(WIN32) && !defined(SYS_OS2)
|
|
if( psz_raw_device != NULL )
|
|
{
|
|
_dvdcss_raw_open( dvdcss, psz_raw_device );
|
|
}
|
|
#endif
|
|
|
|
/* Seek at the beginning, just for safety. */
|
|
dvdcss->pf_seek( dvdcss, 0 );
|
|
|
|
return dvdcss;
|
|
}
|
|
|
|
/**
|
|
* \brief Return a string containing the latest error that occurred in the
|
|
* given \e libdvdcss instance.
|
|
*
|
|
* \param dvdcss a \e libdvdcss instance.
|
|
* \return a null-terminated string containing the latest error message.
|
|
*
|
|
* This function returns a constant string containing the latest error that
|
|
* occurred in \e libdvdcss. It can be used to format error messages at your
|
|
* convenience in your application.
|
|
*/
|
|
LIBDVDCSS_EXPORT char * dvdcss_error ( dvdcss_t dvdcss )
|
|
{
|
|
return dvdcss->psz_error;
|
|
}
|
|
|
|
/**
|
|
* \brief Seek in the disc and change the current key if requested.
|
|
*
|
|
* \param dvdcss a \e libdvdcss instance.
|
|
* \param i_blocks an absolute block offset to seek to.
|
|
* \param i_flags #DVDCSS_NOFLAGS, optionally ored with one of #DVDCSS_SEEK_KEY
|
|
* or #DVDCSS_SEEK_MPEG.
|
|
* \return the new position in blocks, or a negative value in case an error
|
|
* happened.
|
|
*
|
|
* This function seeks to the requested position, in logical blocks.
|
|
*
|
|
* You typically set \p i_flags to #DVDCSS_NOFLAGS when seeking in a .IFO.
|
|
*
|
|
* If #DVDCSS_SEEK_MPEG is specified in \p i_flags and if \e libdvdcss finds it
|
|
* reasonable to do so (ie, if the dvdcss method is not "title"), the current
|
|
* title key will be checked and a new one will be calculated if necessary.
|
|
* This flag is typically used when reading data from a VOB.
|
|
*
|
|
* If #DVDCSS_SEEK_KEY is specified, the title key will be always checked,
|
|
* even with the "title" method. This is equivalent to using the now
|
|
* deprecated dvdcss_title() call. This flag is typically used when seeking
|
|
* in a new title.
|
|
*/
|
|
LIBDVDCSS_EXPORT int dvdcss_seek ( dvdcss_t dvdcss, int i_blocks, int i_flags )
|
|
{
|
|
/* title cracking method is too slow to be used at each seek */
|
|
if( ( ( i_flags & DVDCSS_SEEK_MPEG )
|
|
&& ( dvdcss->i_method != DVDCSS_METHOD_TITLE ) )
|
|
|| ( i_flags & DVDCSS_SEEK_KEY ) )
|
|
{
|
|
/* check the title key */
|
|
if( _dvdcss_title( dvdcss, i_blocks ) )
|
|
{
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return dvdcss->pf_seek( dvdcss, i_blocks );
|
|
}
|
|
|
|
/**
|
|
* \brief Read from the disc and decrypt data if requested.
|
|
*
|
|
* \param dvdcss a \e libdvdcss instance.
|
|
* \param p_buffer a buffer that will contain the data read from the disc.
|
|
* \param i_blocks the amount of blocks to read.
|
|
* \param i_flags #DVDCSS_NOFLAGS, optionally ored with #DVDCSS_READ_DECRYPT.
|
|
* \return the amount of blocks read, or a negative value in case an
|
|
* error happened.
|
|
*
|
|
* This function reads \p i_blocks logical blocks from the DVD.
|
|
*
|
|
* You typically set \p i_flags to #DVDCSS_NOFLAGS when reading data from a
|
|
* .IFO file on the DVD.
|
|
*
|
|
* If #DVDCSS_READ_DECRYPT is specified in \p i_flags, dvdcss_read() will
|
|
* automatically decrypt scrambled sectors. This flag is typically used when
|
|
* reading data from a .VOB file on the DVD. It has no effect on unscrambled
|
|
* discs or unscrambled sectors, and can be safely used on those.
|
|
*
|
|
* \warning dvdcss_read() expects to be able to write \p i_blocks *
|
|
* #DVDCSS_BLOCK_SIZE bytes in \p p_buffer.
|
|
*/
|
|
LIBDVDCSS_EXPORT int dvdcss_read ( dvdcss_t dvdcss, void *p_buffer,
|
|
int i_blocks,
|
|
int i_flags )
|
|
{
|
|
int i_ret, i_index;
|
|
|
|
i_ret = dvdcss->pf_read( dvdcss, p_buffer, i_blocks );
|
|
|
|
if( i_ret <= 0
|
|
|| !dvdcss->b_scrambled
|
|
|| !(i_flags & DVDCSS_READ_DECRYPT) )
|
|
{
|
|
return i_ret;
|
|
}
|
|
|
|
if( ! memcmp( dvdcss->css.p_title_key, "\0\0\0\0\0", 5 ) )
|
|
{
|
|
/* For what we believe is an unencrypted title,
|
|
* check that there are no encrypted blocks */
|
|
for( i_index = i_ret; i_index; i_index-- )
|
|
{
|
|
if( ((uint8_t*)p_buffer)[0x14] & 0x30 )
|
|
{
|
|
print_error( dvdcss, "no key but found encrypted block" );
|
|
/* Only return the initial range of unscrambled blocks? */
|
|
/* or fail completely? return 0; */
|
|
break;
|
|
}
|
|
p_buffer = (void *) ((uint8_t *)p_buffer + DVDCSS_BLOCK_SIZE);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* Decrypt the blocks we managed to read */
|
|
for( i_index = i_ret; i_index; i_index-- )
|
|
{
|
|
_dvdcss_unscramble( dvdcss->css.p_title_key, p_buffer );
|
|
((uint8_t*)p_buffer)[0x14] &= 0x8f;
|
|
p_buffer = (void *) ((uint8_t *)p_buffer + DVDCSS_BLOCK_SIZE);
|
|
}
|
|
}
|
|
|
|
return i_ret;
|
|
}
|
|
|
|
/**
|
|
* \brief Read from the disc into multiple buffers and decrypt data if
|
|
* requested.
|
|
*
|
|
* \param dvdcss a \e libdvdcss instance.
|
|
* \param p_iovec a pointer to an array of iovec structures that will contain
|
|
* the data read from the disc.
|
|
* \param i_blocks the amount of blocks to read.
|
|
* \param i_flags #DVDCSS_NOFLAGS, optionally ored with #DVDCSS_READ_DECRYPT.
|
|
* \return the amount of blocks read, or a negative value in case an
|
|
* error happened.
|
|
*
|
|
* This function reads \p i_blocks logical blocks from the DVD and writes them
|
|
* to an array of iovec structures.
|
|
*
|
|
* You typically set \p i_flags to #DVDCSS_NOFLAGS when reading data from a
|
|
* .IFO file on the DVD.
|
|
*
|
|
* If #DVDCSS_READ_DECRYPT is specified in \p i_flags, dvdcss_readv() will
|
|
* automatically decrypt scrambled sectors. This flag is typically used when
|
|
* reading data from a .VOB file on the DVD. It has no effect on unscrambled
|
|
* discs or unscrambled sectors, and can be safely used on those.
|
|
*
|
|
* \warning dvdcss_readv() expects to be able to write \p i_blocks *
|
|
* #DVDCSS_BLOCK_SIZE bytes in the buffers pointed by \p p_iovec.
|
|
* Moreover, all iov_len members of the iovec structures should be
|
|
* multiples of #DVDCSS_BLOCK_SIZE.
|
|
*/
|
|
LIBDVDCSS_EXPORT int dvdcss_readv ( dvdcss_t dvdcss, void *p_iovec,
|
|
int i_blocks,
|
|
int i_flags )
|
|
{
|
|
struct iovec *_p_iovec = (struct iovec *)p_iovec;
|
|
int i_ret, i_index;
|
|
void *iov_base;
|
|
size_t iov_len;
|
|
|
|
i_ret = dvdcss->pf_readv( dvdcss, _p_iovec, i_blocks );
|
|
|
|
if( i_ret <= 0
|
|
|| !dvdcss->b_scrambled
|
|
|| !(i_flags & DVDCSS_READ_DECRYPT) )
|
|
{
|
|
return i_ret;
|
|
}
|
|
|
|
/* Initialize loop for decryption */
|
|
iov_base = _p_iovec->iov_base;
|
|
iov_len = _p_iovec->iov_len;
|
|
|
|
/* Decrypt the blocks we managed to read */
|
|
for( i_index = i_ret; i_index; i_index-- )
|
|
{
|
|
/* Check that iov_len is a multiple of 2048 */
|
|
if( iov_len & 0x7ff )
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
while( iov_len == 0 )
|
|
{
|
|
_p_iovec++;
|
|
iov_base = _p_iovec->iov_base;
|
|
iov_len = _p_iovec->iov_len;
|
|
}
|
|
|
|
_dvdcss_unscramble( dvdcss->css.p_title_key, iov_base );
|
|
((uint8_t*)iov_base)[0x14] &= 0x8f;
|
|
|
|
iov_base = (void *) ((uint8_t*)iov_base + DVDCSS_BLOCK_SIZE);
|
|
iov_len -= DVDCSS_BLOCK_SIZE;
|
|
}
|
|
|
|
return i_ret;
|
|
}
|
|
|
|
/**
|
|
* \brief Close the DVD and clean up the library.
|
|
*
|
|
* \param dvdcss a \e libdvdcss instance.
|
|
* \return zero in case of success, a negative value otherwise.
|
|
*
|
|
* This function closes the DVD device and frees all the memory allocated
|
|
* by \e libdvdcss. On return, the #dvdcss_t is invalidated and may not be
|
|
* used again.
|
|
*/
|
|
LIBDVDCSS_EXPORT int dvdcss_close ( dvdcss_t dvdcss )
|
|
{
|
|
dvd_title_t *p_title;
|
|
int i_ret;
|
|
|
|
/* Free our list of keys */
|
|
p_title = dvdcss->p_titles;
|
|
while( p_title )
|
|
{
|
|
dvd_title_t *p_tmptitle = p_title->p_next;
|
|
free( p_title );
|
|
p_title = p_tmptitle;
|
|
}
|
|
|
|
i_ret = _dvdcss_close( dvdcss );
|
|
|
|
if( i_ret < 0 )
|
|
{
|
|
return i_ret;
|
|
}
|
|
|
|
free( dvdcss->psz_device );
|
|
free( dvdcss );
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Deprecated. See dvdcss_seek().
|
|
*/
|
|
#undef dvdcss_title
|
|
LIBDVDCSS_EXPORT int dvdcss_title ( dvdcss_t dvdcss, int i_block )
|
|
{
|
|
return _dvdcss_title( dvdcss, i_block );
|
|
}
|
|
|
|
/**
|
|
* \brief Return 1 if the DVD is scrambled, 0 otherwise.
|
|
*
|
|
* \param dvdcss a \e libdvdcss instance.
|
|
* \return 1 if the DVD is scrambled, 0 otherwise.
|
|
*
|
|
* This function returns whether the DVD is scrambled.
|
|
*/
|
|
LIBDVDCSS_EXPORT int dvdcss_is_scrambled ( dvdcss_t dvdcss )
|
|
{
|
|
return dvdcss->b_scrambled;
|
|
}
|
|
|