mirror of https://github.com/mpv-player/mpv
799 lines
24 KiB
C
799 lines
24 KiB
C
/* libdvdcss.c: DVD reading library.
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*
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* Authors: Stéphane Borel <stef@via.ecp.fr>
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* Samuel Hocevar <sam@zoy.org>
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* Håkan Hjort <d95hjort@dtek.chalmers.se>
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*
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* Copyright (C) 1998-2002 VideoLAN
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*
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* Modified for use with MPlayer, changes contained in libdvdcss_changes.diff.
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* detailed changelog at http://svn.mplayerhq.hu/mplayer/trunk/
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* $Id$
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
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*/
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/**
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* \mainpage libdvdcss developer documentation
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*
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* \section intro Introduction
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*
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* \e libdvdcss is a simple library designed for accessing DVDs like a block
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* device without having to bother about the decryption. The important features
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* are:
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* \li portability: currently supported platforms are GNU/Linux, FreeBSD,
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* NetBSD, OpenBSD, BSD/OS, BeOS, Windows 95/98, Windows NT/2000, MacOS X,
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* Solaris, HP-UX and OS/2.
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* \li adaptability: unlike most similar projects, libdvdcss doesn't require
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* the region of your drive to be set and will try its best to read from
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* the disc even in the case of a region mismatch.
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* \li simplicity: a DVD player can be built around the \e libdvdcss API using
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* no more than 4 or 5 library calls.
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*
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* \e libdvdcss is free software, released under the General Public License.
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* This ensures that \e libdvdcss remains free and used only with free
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* software.
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*
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* \section api The libdvdcss API
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*
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* The complete \e libdvdcss programming interface is documented in the
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* dvdcss.h file.
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*
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* \section env Environment variables
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*
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* Some environment variables can be used to change the behaviour of
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* \e libdvdcss without having to modify the program which uses it. These
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* variables are:
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*
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* \li \b DVDCSS_VERBOSE: sets the verbosity level.
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* - \c 0 outputs no messages at all.
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* - \c 1 outputs error messages to stderr.
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* - \c 2 outputs error messages and debug messages to stderr.
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*
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* \li \b DVDCSS_METHOD: sets the authentication and decryption method
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* that \e libdvdcss will use to read scrambled discs. Can be one
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* of \c title, \c key or \c disc.
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* - \c key is the default method. \e libdvdcss will use a set of
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* calculated player keys to try and get the disc key. This can fail
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* if the drive does not recognize any of the player keys.
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* - \c disc is a fallback method when \c key has failed. Instead of
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* using player keys, \e libdvdcss will crack the disc key using
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* a brute force algorithm. This process is CPU intensive and requires
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* 64 MB of memory to store temporary data.
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* - \c title is the fallback when all other methods have failed. It does
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* not rely on a key exchange with the DVD drive, but rather uses a
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* crypto attack to guess the title key. On rare cases this may fail
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* because there is not enough encrypted data on the disc to perform
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* a statistical attack, but in the other hand it is the only way to
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* decrypt a DVD stored on a hard disc, or a DVD with the wrong region
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* on an RPC2 drive.
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*
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* \li \b DVDCSS_RAW_DEVICE: specify the raw device to use. Exact usage will
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* depend on your operating system, the Linux utility to set up raw devices
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* is \c raw(8) for instance. Please note that on most operating systems,
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* using a raw device requires highly aligned buffers: Linux requires a
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* 2048 bytes alignment (which is the size of a DVD sector).
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*
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* \li \b DVDCSS_CACHE: specify a directory in which to store title key
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* values. This will speed up descrambling of DVDs which are in the
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* cache. The DVDCSS_CACHE directory is created if it does not exist,
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* and a subdirectory is created named after the DVD's title or
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* manufacturing date. If DVDCSS_CACHE is not set or is empty, \e libdvdcss
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* will use the default value which is "${HOME}/.dvdcss/" under Unix and
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* "C:\Documents and Settings\$USER\Application Data\dvdcss\" under Win32.
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* The special value "off" disables caching.
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*/
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/*
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* Preamble
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*/
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#include "config.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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#ifdef HAVE_SYS_PARAM_H
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# include <sys/param.h>
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#endif
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#ifdef HAVE_PWD_H
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# include <pwd.h>
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#endif
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#include <fcntl.h>
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#include <errno.h>
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#ifdef HAVE_UNISTD_H
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# include <unistd.h>
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#endif
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#ifdef HAVE_LIMITS_H
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# include <limits.h>
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#endif
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#ifdef HAVE_DIRECT_H
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# include <direct.h>
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#endif
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#include "dvdcss.h"
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#include "common.h"
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#include "css.h"
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#include "libdvdcss.h"
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#include "ioctl.h"
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#include "device.h"
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/**
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* \brief Symbol for version checks.
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*
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* The name of this symbol contains the library major number, which makes it
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* easy to check which \e libdvdcss development headers are installed on the
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* system with tools such as autoconf.
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*
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* The variable itself contains the exact version number of the library,
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* which can be useful for specific feature needs.
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*/
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char * dvdcss_interface_2 = VERSION;
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/**
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* \brief Open a DVD device or directory and return a dvdcss instance.
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*
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* \param psz_target a string containing the target name, for instance
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* "/dev/hdc" or "E:".
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* \return a handle to a dvdcss instance or NULL on error.
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*
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* Initialize the \e libdvdcss library and open the requested DVD device or
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* directory. \e libdvdcss checks whether ioctls can be performed on the disc,
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* and when possible, the disc key is retrieved.
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*
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* dvdcss_open() returns a handle to be used for all subsequent \e libdvdcss
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* calls. If an error occured, NULL is returned.
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*/
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extern dvdcss_t dvdcss_open ( char *psz_target )
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{
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char psz_buffer[PATH_MAX];
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int i_ret;
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char *psz_method = getenv( "DVDCSS_METHOD" );
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char *psz_verbose = getenv( "DVDCSS_VERBOSE" );
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char *psz_cache = getenv( "DVDCSS_CACHE" );
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#ifndef WIN32
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char *psz_raw_device = getenv( "DVDCSS_RAW_DEVICE" );
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#endif
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dvdcss_t dvdcss;
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/*
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* Allocate the library structure
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*/
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dvdcss = malloc( sizeof( struct dvdcss_s ) );
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if( dvdcss == NULL )
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{
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return NULL;
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}
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/*
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* Initialize structure with default values
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*/
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#ifndef WIN32
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dvdcss->i_raw_fd = -1;
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#endif
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dvdcss->p_titles = NULL;
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dvdcss->psz_device = (char *)strdup( psz_target );
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dvdcss->psz_error = "no error";
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dvdcss->i_method = DVDCSS_METHOD_KEY;
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dvdcss->psz_cachefile[0] = '\0';
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dvdcss->b_debug = 0;
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dvdcss->b_errors = 0;
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/*
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* Find verbosity from DVDCSS_VERBOSE environment variable
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*/
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if( psz_verbose != NULL )
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{
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int i = atoi( psz_verbose );
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if( i >= 2 ) dvdcss->b_debug = i;
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if( i >= 1 ) dvdcss->b_errors = 1;
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}
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/*
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* Find method from DVDCSS_METHOD environment variable
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*/
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if( psz_method != NULL )
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{
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if( !strncmp( psz_method, "key", 4 ) )
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{
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dvdcss->i_method = DVDCSS_METHOD_KEY;
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}
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else if( !strncmp( psz_method, "disc", 5 ) )
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{
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dvdcss->i_method = DVDCSS_METHOD_DISC;
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}
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else if( !strncmp( psz_method, "title", 5 ) )
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{
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dvdcss->i_method = DVDCSS_METHOD_TITLE;
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}
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else
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{
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print_error( dvdcss, "unknown decrypt method, please choose "
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"from 'title', 'key' or 'disc'" );
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free( dvdcss->psz_device );
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free( dvdcss );
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return NULL;
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}
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}
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/*
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* If DVDCSS_CACHE was not set, try to guess a default value
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*/
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if( psz_cache == NULL || psz_cache[0] == '\0' )
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{
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#ifdef HAVE_DIRECT_H
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typedef HRESULT( WINAPI *SHGETFOLDERPATH )
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( HWND, int, HANDLE, DWORD, LPTSTR );
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# define CSIDL_FLAG_CREATE 0x8000
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# define CSIDL_APPDATA 0x1A
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# define SHGFP_TYPE_CURRENT 0
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char psz_home[MAX_PATH];
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HINSTANCE p_dll;
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SHGETFOLDERPATH p_getpath;
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*psz_home = '\0';
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/* Load the shfolder dll to retrieve SHGetFolderPath */
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p_dll = LoadLibrary( "shfolder.dll" );
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if( p_dll )
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{
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p_getpath = (void*)GetProcAddress( p_dll, "SHGetFolderPathA" );
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if( p_getpath )
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{
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/* Get the "Application Data" folder for the current user */
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if( p_getpath( NULL, CSIDL_APPDATA | CSIDL_FLAG_CREATE,
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NULL, SHGFP_TYPE_CURRENT, psz_home ) == S_OK )
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{
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FreeLibrary( p_dll );
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}
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else
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{
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*psz_home = '\0';
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}
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}
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FreeLibrary( p_dll );
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}
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/* Cache our keys in
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* C:\Documents and Settings\$USER\Application Data\dvdcss\ */
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if( *psz_home )
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{
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snprintf( psz_buffer, PATH_MAX, "%s/dvdcss", psz_home );
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psz_buffer[PATH_MAX-1] = '\0';
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psz_cache = psz_buffer;
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}
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#else
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char *psz_home = NULL;
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# ifdef HAVE_PWD_H
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struct passwd *p_pwd;
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/* Try looking in password file for home dir. */
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p_pwd = getpwuid(getuid());
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if( p_pwd )
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{
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psz_home = p_pwd->pw_dir;
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}
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# endif
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if( psz_home == NULL )
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{
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psz_home = getenv( "HOME" );
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}
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if( psz_home == NULL )
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{
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psz_home = getenv( "USERPROFILE" );
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}
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/* Cache our keys in ${HOME}/.dvdcss/ */
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if( psz_home )
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{
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snprintf( psz_buffer, PATH_MAX, "%s/.dvdcss", psz_home );
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psz_buffer[PATH_MAX-1] = '\0';
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psz_cache = psz_buffer;
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}
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#endif
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}
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/*
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* Find cache dir from the DVDCSS_CACHE environment variable
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*/
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if( psz_cache != NULL )
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{
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if( psz_cache[0] == '\0' || !strcmp( psz_cache, "off" ) )
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{
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psz_cache = NULL;
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}
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/* Check that we can add the ID directory and the block filename */
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else if( strlen( psz_cache ) + 1 + 32 + 1 + (KEY_SIZE * 2) + 10 + 1
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> PATH_MAX )
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{
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print_error( dvdcss, "cache directory name is too long" );
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psz_cache = NULL;
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}
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}
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/*
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* Open device
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*/
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i_ret = _dvdcss_open( dvdcss );
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if( i_ret < 0 )
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{
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free( dvdcss->psz_device );
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free( dvdcss );
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return NULL;
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}
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dvdcss->b_scrambled = 1; /* Assume the worst */
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dvdcss->b_ioctls = _dvdcss_use_ioctls( dvdcss );
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if( dvdcss->b_ioctls )
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{
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i_ret = _dvdcss_test( dvdcss );
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if( i_ret < 0 )
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{
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/* Disable the CSS ioctls and hope that it works? */
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print_debug( dvdcss,
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"could not check whether the disc was scrambled" );
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dvdcss->b_ioctls = 0;
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}
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else
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{
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print_debug( dvdcss, i_ret ? "disc is scrambled"
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: "disc is unscrambled" );
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dvdcss->b_scrambled = i_ret;
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}
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}
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/* If disc is CSS protected and the ioctls work, authenticate the drive */
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if( dvdcss->b_scrambled && dvdcss->b_ioctls )
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{
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i_ret = _dvdcss_disckey( dvdcss );
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if( i_ret < 0 )
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{
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_dvdcss_close( dvdcss );
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free( dvdcss->psz_device );
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free( dvdcss );
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return NULL;
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}
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}
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/* If the cache is enabled, write the cache directory tag */
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if( psz_cache )
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{
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char *psz_tag = "Signature: 8a477f597d28d172789f06886806bc55\r\n"
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"# This file is a cache directory tag created by libdvdcss.\r\n"
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"# For information about cache directory tags, see:\r\n"
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"# http://www.brynosaurus.com/cachedir/\r\n";
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unsigned char psz_tagfile[PATH_MAX+1+12+1];
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int i_fd;
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sprintf( psz_tagfile, "%s/CACHEDIR.TAG", psz_cache );
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i_fd = open( psz_tagfile, O_RDWR|O_CREAT, 0644 );
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if( i_fd >= 0 )
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{
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write( i_fd, psz_tag, strlen(psz_tag) );
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close( i_fd );
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}
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}
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/* If the cache is enabled, extract a unique disc ID */
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if( psz_cache )
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{
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uint8_t p_sector[DVDCSS_BLOCK_SIZE];
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unsigned char psz_debug[PATH_MAX+30];
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unsigned char psz_key[1 + KEY_SIZE * 2 + 1];
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unsigned char * psz_title, * psz_serial;
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int i;
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/* We read sector 0. If it starts with 0x000001ba (BE), we are
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* reading a VOB file, and we should not cache anything. */
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i_ret = dvdcss->pf_seek( dvdcss, 0 );
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if( i_ret != 0 )
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{
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goto nocache;
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}
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i_ret = dvdcss->pf_read( dvdcss, p_sector, 1 );
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if( i_ret != 1 )
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{
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goto nocache;
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}
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if( p_sector[0] == 0x00 && p_sector[1] == 0x00
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&& p_sector[2] == 0x01 && p_sector[3] == 0xba )
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{
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goto nocache;
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}
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|
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/* The data we are looking for is at sector 16 (32768 bytes):
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* - offset 40: disc title (32 uppercase chars)
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* - offset 813: manufacturing date + serial no (16 digits) */
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i_ret = dvdcss->pf_seek( dvdcss, 16 );
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if( i_ret != 16 )
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{
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goto nocache;
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}
|
|
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i_ret = dvdcss->pf_read( dvdcss, p_sector, 1 );
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if( i_ret != 1 )
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{
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goto nocache;
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}
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|
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/* Get the disc title */
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psz_title = p_sector + 40;
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psz_title[32] = '\0';
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for( i = 0 ; i < 32 ; i++ )
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{
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if( psz_title[i] <= ' ' )
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{
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psz_title[i] = '\0';
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break;
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}
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else if( psz_title[i] == '/' || psz_title[i] == '\\' )
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{
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psz_title[i] = '-';
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}
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}
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/* Get the date + serial */
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psz_serial = p_sector + 813;
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psz_serial[16] = '\0';
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/* Check that all characters are digits, otherwise convert. */
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for( i = 0 ; i < 16 ; i++ )
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{
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if( psz_serial[i] < '0' || psz_serial[i] > '9' )
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{
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unsigned char psz_tmp[16 + 1];
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sprintf( psz_tmp,
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"%.2x%.2x%.2x%.2x%.2x%.2x%.2x%.2x",
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psz_serial[0], psz_serial[1], psz_serial[2],
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psz_serial[3], psz_serial[4], psz_serial[5],
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psz_serial[6], psz_serial[7] );
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memcpy( psz_serial, psz_tmp, 16 );
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break;
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}
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}
|
|
|
|
/* Get disk key, since some discs have got same title, manufacturing
|
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* date and serial number, but different keys */
|
|
if( dvdcss->b_scrambled )
|
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{
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psz_key[0] = '-';
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for( i = 0; i < KEY_SIZE; i++ )
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{
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sprintf( &psz_key[1+i*2], "%.2x", dvdcss->css.p_disc_key[i] );
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}
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psz_key[1 + KEY_SIZE * 2] = '\0';
|
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}
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else
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{
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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;
|
|
|
|
sprintf( psz_debug, "using CSS key cache dir: %s",
|
|
dvdcss->psz_cachefile );
|
|
print_debug( dvdcss, psz_debug );
|
|
}
|
|
nocache:
|
|
|
|
#ifndef WIN32
|
|
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 occured 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
|
|
* occured in \e libdvdcss. It can be used to format error messages at your
|
|
* convenience in your application.
|
|
*/
|
|
extern 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.
|
|
*/
|
|
extern 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.
|
|
*/
|
|
extern 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.
|
|
*/
|
|
extern 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.
|
|
*/
|
|
extern 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
|
|
extern int dvdcss_title ( dvdcss_t dvdcss, int i_block )
|
|
{
|
|
return _dvdcss_title( dvdcss, i_block );
|
|
}
|
|
|