ref: 68b19d058bc17060167acf89a5650160aaf63610
parent: 5084f4c8bc77f27e1f3ae43bca348c9b7fcd82be
author: Sam Hocevar <sam@videolan.org>
date: Sun Jun 2 12:05:34 EDT 2002
* ./src/css.c: applied Håkan's fix for the failure on region mismatch.
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,7 @@
HEAD
+ * ./src/css.c: applied H�kan's fix for the failure on region mismatch.
* ALL: switched to libtool 1.4.2a.
* ./src/libdvdcss.c: fixed an uninitialized variable.
--- a/src/css.c
+++ b/src/css.c
@@ -2,7 +2,7 @@
* css.c: Functions for DVD authentification and unscrambling
*****************************************************************************
* Copyright (C) 1999-2001 VideoLAN
- * $Id: css.c,v 1.8 2002/05/16 20:12:04 hjort Exp $
+ * $Id: css.c,v 1.9 2002/06/02 16:05:34 sam Exp $
*
* Author: St�phane Borel <stef@via.ecp.fr>
* H�kan Hjort <d95hjort@dtek.chalmers.se>
@@ -295,7 +295,7 @@
return -1;
}
- /* Unencrypt disc key using bus key */
+ /* Decrypt disc key using bus key */
for( i = 0 ; i < 2048 ; i++ )
{p_buffer[ i ] ^= dvdcss->css.p_bus_key[ 4 - (i % KEY_SIZE) ];
@@ -345,17 +345,11 @@
u8 p_key[KEY_SIZE];
int i, i_ret = 0;
- if( ( dvdcss->i_method == DVDCSS_METHOD_TITLE )
- || ( dvdcss->b_ioctls == 0 ) )
+ if( dvdcss->b_ioctls && ( dvdcss->i_method == DVDCSS_METHOD_KEY ||
+ dvdcss->i_method == DVDCSS_METHOD_DISC ) )
{- /* For now, the limit is 9Gb / 2048 = 4718592 sectors. */
- i_ret = CSSTitleCrack( dvdcss, i_pos, 4718592, p_key);
- }
- else
- {- /*
- * if we are here we have a decrypted disc key and ioctls are available
- * so we can read the title key and decrypt it.
+ /* We have a decrypted Disc key and the ioctls are available,
+ * read the title key and decrypt it.
*/
_dvdcss_debug( dvdcss, "decrypting title key with disc key" );
@@ -380,43 +374,66 @@
case -1:
/* An error getting the ASF status, something must be wrong. */
// ioctl_InvalidateAgid( dvdcss->i_fd, &dvdcss->css.i_agid );
- return -1;
+ _dvdcss_debug( dvdcss, "lost ASF reqesting Title key" );
+ i_ret = -1;
+ break;
case 0:
- /* This might either be an title that has no key,
+ /* This might either be a title that has no key,
* or we encountered a region error. */
- _dvdcss_debug( dvdcss, "Lost ASF reqesting Title key" );
- return i_ret;
+ _dvdcss_debug( dvdcss, "lost ASF reqesting Title key" );
+ break;
case 1:
- /* Drive status is ok, check if we got the title key. */
- if( i_ret )
- {- /* The request failed but we didn't lose ASF. */
- //ioctl_InvalidateAgid( dvdcss->i_fd, &dvdcss->css.i_agid );
- return i_ret;
- }
+ /* Drive status is ok. */
+ /* If the title key request failed, but we did not loose ASF,
+ * we might stil have the AGID. Other code assume that we
+ * will not after this so invalidate it(?). */
+ if( i_ret < 0 )
+ {+ //ioctl_InvalidateAgid( dvdcss->i_fd, &dvdcss->css.i_agid );
+ }
break;
}
+
+ if( !( i_ret < 0 ) )
+ {+ /* Decrypt title key using the bus key */
+ for( i = 0 ; i < KEY_SIZE ; i++ )
+ {+ p_key[ i ] ^= dvdcss->css.p_bus_key[ 4 - (i % KEY_SIZE) ];
+ }
- /* Unencrypt title key using the bus key */
- for( i = 0 ; i < KEY_SIZE ; i++ )
- {- p_key[ i ] ^= dvdcss->css.p_bus_key[ 4 - (i % KEY_SIZE) ];
- }
+ /* If p_key is all zero then there realy wasn't any key pressent
+ * even though we got to read it without an error. */
+ if( !( p_key[0] | p_key[1] | p_key[2] | p_key[3] | p_key[4] ) )
+ {+ i_ret = 0;
+ }
+ else
+ {+ CSSDecryptTitleKey( dvdcss->css.p_disc_key, p_key );
+ i_ret = 1;
+ }
- /* If p_key is all zero then there realy wasn't any key pressent
- * even though we got to read it without an error. */
- if( !( p_key[0] | p_key[1] | p_key[2] | p_key[3] | p_key[4] ) )
- {- i_ret = 0;
- }
- else
- {- CSSDecryptTitleKey( dvdcss->css.p_disc_key, p_key );
- i_ret = 1;
- }
+ /* All went well either there wasn't a key or we have it now. */
+ memcpy( p_title_key, p_key, KEY_SIZE );
+ CSSPrintKey( dvdcss, p_title_key );
+
+ return i_ret;
+ }
+
+ /* The title key request failed */
+ _dvdcss_debug( dvdcss, "Reverting to cracking the Title key" );
+
+ /* FALL THROUGH */
}
+
+ /* METHOD is TITLE, we can't use the ioctls or requesting the title key
+ * failed above. For these cases we try to crack the key instead. */
+
+ /* For now, the read limit is 9Gb / 2048 = 4718592 sectors. */
+ i_ret = CSSTitleCrack( dvdcss, i_pos, 4718592, p_key);
memcpy( p_title_key, p_key, KEY_SIZE );
CSSPrintKey( dvdcss, p_title_key );