User: Peter Hernberg

My two bronze chits

On: Athlon Motherboards And Chipsets Under Linux

My Athlon 700 (upgraded from a 500) K7M rig works like a dream. I run linux as my primary OS and I haven't had a lick of trouble. The Athlon is an awesome chip and when people talk about compatablility troubles, it's probably just Intel FUD. There were some early problems with inadequate power supplies (these things can happen when the silicon contains 22 million transistors), but the they're pretty much gone now, due to better power supplies and AMD's conversion to the new .18 micron process. Bottom line: don't, don't, don't be scared out of buying an athlon because of linux compatability fears

Living in a Free Country means I can do this!

On: Preliminary Injunction Issued in DVD CCA Case

/*
* css_descramble.c
*
* Released under the version 2 of the GPL.
*
* Copyright 1999 Derek Fawcus
*
* This file contains functions to descramble CSS encrypted DVD content
*
*/

/*
* Still in progress: Remove the use of the bit_reverse[] table by recoding
* the generation of LFSR1. Finish combining this with
* the css authentication code.
*
*/

#include
#include
#include "css-descramble.h"

typedef unsigned char byte;

/*
*
* some tables used for descrambling sectors and/or decrypting title keys
*
*/

static byte csstab1[256]=
{
0x33,0x73,0x3b,0x26,0x63,0x23,0x6b,0x76,0x3e,0x7e, 0x36,0x2b,0x6e,0x2e,0x66,0x7b,
0xd3,0x93,0xdb,0x06,0x43,0x03,0x4b,0x96,0xde,0x9e, 0xd6,0x0b,0x4e,0x0e,0x46,0x9b,
0x57,0x17,0x5f,0x82,0xc7,0x87,0xcf,0x12,0x5a,0x1a, 0x52,0x8f,0xca,0x8a,0xc2,0x1f,
0xd9,0x99,0xd1,0x00,0x49,0x09,0x41,0x90,0xd8,0x98, 0xd0,0x01,0x48,0x08,0x40,0x91,
0x3d,0x7d,0x35,0x24,0x6d,0x2d,0x65,0x74,0x3c,0x7c, 0x34,0x25,0x6c,0x2c,0x64,0x75,
0xdd,0x9d,0xd5,0x04,0x4d,0x0d,0x45,0x94,0xdc,0x9c, 0xd4,0x05,0x4c,0x0c,0x44,0x95,
0x59,0x19,0x51,0x80,0xc9,0x89,0xc1,0x10,0x58,0x18, 0x50,0x81,0xc8,0x88,0xc0,0x11,
0xd7,0x97,0xdf,0x02,0x47,0x07,0x4f,0x92,0xda,0x9a, 0xd2,0x0f,0x4a,0x0a,0x42,0x9f,
0x53,0x13,0x5b,0x86,0xc3,0x83,0xcb,0x16,0x5e,0x1e, 0x56,0x8b,0xce,0x8e,0xc6,0x1b,
0xb3,0xf3,0xbb,0xa6,0xe3,0xa3,0xeb,0xf6,0xbe,0xfe, 0xb6,0xab,0xee,0xae,0xe6,0xfb,
0x37,0x77,0x3f,0x22,0x67,0x27,0x6f,0x72,0x3a,0x7a, 0x32,0x2f,0x6a,0x2a,0x62,0x7f,
0xb9,0xf9,0xb1,0xa0,0xe9,0xa9,0xe1,0xf0,0xb8,0xf8, 0xb0,0xa1,0xe8,0xa8,0xe0,0xf1,
0x5d,0x1d,0x55,0x84,0xcd,0x8d,0xc5,0x14,0x5c,0x1c, 0x54,0x85,0xcc,0x8c,0xc4,0x15,
0xbd,0xfd,0xb5,0xa4,0xed,0xad,0xe5,0xf4,0xbc,0xfc, 0xb4,0xa5,0xec,0xac,0xe4,0xf5,
0x39,0x79,0x31,0x20,0x69,0x29,0x61,0x70,0x38,0x78, 0x30,0x21,0x68,0x28,0x60,0x71,
0xb7,0xf7,0xbf,0xa2,0xe7,0xa7,0xef,0xf2,0xba,0xfa, 0xb2,0xaf,0xea,0xaa,0xe2,0xff
};

static byte lfsr1_bits0[256]=
{
0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x09,0x08, 0x0b,0x0a,0x0d,0x0c,0x0f,0x0e,
0x12,0x13,0x10,0x11,0x16,0x17,0x14,0x15,0x1b,0x1a, 0x19,0x18,0x1f,0x1e,0x1d,0x1c,
0x24,0x25,0x26,0x27,0x20,0x21,0x22,0x23,0x2d,0x2c, 0x2f,0x2e,0x29,0x28,0x2b,0x2a,
0x36,0x37,0x34,0x35,0x32,0x33,0x30,0x31,0x3f,0x3e, 0x3d,0x3c,0x3b,0x3a,0x39,0x38,
0x49,0x48,0x4b,0x4a,0x4d,0x4c,0x4f,0x4e,0x40,0x41, 0x42,0x43,0x44,0x45,0x46,0x47,
0x5b,0x5a,0x59,0x58,0x5f,0x5e,0x5d,0x5c,0x52,0x53, 0x50,0x51,0x56,0x57,0x54,0x55,
0x6d,0x6c,0x6f,0x6e,0x69,0x68,0x6b,0x6a,0x64,0x65, 0x66,0x67,0x60,0x61,0x62,0x63,
0x7f,0x7e,0x7d,0x7c,0x7b,0x7a,0x79,0x78,0x76,0x77, 0x74,0x75,0x72,0x73,0x70,0x71,
0x92,0x93,0x90,0x91,0x96,0x97,0x94,0x95,0x9b,0x9a, 0x99,0x98,0x9f,0x9e,0x9d,0x9c,
0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x89,0x88, 0x8b,0x8a,0x8d,0x8c,0x8f,0x8e,
0xb6,0xb7,0xb4,0xb5,0xb2,0xb3,0xb0,0xb1,0xbf,0xbe, 0xbd,0xbc,0xbb,0xba,0xb9,0xb8,
0xa4,0xa5,0xa6,0xa7,0xa0,0xa1,0xa2,0xa3,0xad,0xac, 0xaf,0xae,0xa9,0xa8,0xab,0xaa,
0xdb,0xda,0xd9,0xd8,0xdf,0xde,0xdd,0xdc,0xd2,0xd3, 0xd0,0xd1,0xd6,0xd7,0xd4,0xd5,
0xc9,0xc8,0xcb,0xca,0xcd,0xcc,0xcf,0xce,0xc0,0xc1, 0xc2,0xc3,0xc4,0xc5,0xc6,0xc7,
0xff,0xfe,0xfd,0xfc,0xfb,0xfa,0xf9,0xf8,0xf6,0xf7, 0xf4,0xf5,0xf2,0xf3,0xf0,0xf1,
0xed,0xec,0xef,0xee,0xe9,0xe8,0xeb,0xea,0xe4,0xe5, 0xe6,0xe7,0xe0,0xe1,0xe2,0xe3
};

static byte lfsr1_bits1[512]=
{
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff,
0x00,0x24,0x49,0x6d,0x92,0xb6,0xdb,0xff,0x00,0x24, 0x49,0x6d,0x92,0xb6,0xdb,0xff
};

/* Reverse the order of the bits within a byte.
*/
static byte bit_reverse[256]=
{
0x00,0x80,0x40,0xc0,0x20,0xa0,0x60,0xe0,0x10,0x90, 0x50,0xd0,0x30,0xb0,0x70,0xf0,
0x08,0x88,0x48,0xc8,0x28,0xa8,0x68,0xe8,0x18,0x98, 0x58,0xd8,0x38,0xb8,0x78,0xf8,
0x04,0x84,0x44,0xc4,0x24,0xa4,0x64,0xe4,0x14,0x94, 0x54,0xd4,0x34,0xb4,0x74,0xf4,
0x0c,0x8c,0x4c,0xcc,0x2c,0xac,0x6c,0xec,0x1c,0x9c, 0x5c,0xdc,0x3c,0xbc,0x7c,0xfc,
0x02,0x82,0x42,0xc2,0x22,0xa2,0x62,0xe2,0x12,0x92, 0x52,0xd2,0x32,0xb2,0x72,0xf2,
0x0a,0x8a,0x4a,0xca,0x2a,0xaa,0x6a,0xea,0x1a,0x9a, 0x5a,0xda,0x3a,0xba,0x7a,0xfa,
0x06,0x86,0x46,0xc6,0x26,0xa6,0x66,0xe6,0x16,0x96, 0x56,0xd6,0x36,0xb6,0x76,0xf6,
0x0e,0x8e,0x4e,0xce,0x2e,0xae,0x6e,0xee,0x1e,0x9e, 0x5e,0xde,0x3e,0xbe,0x7e,0xfe,
0x01,0x81,0x41,0xc1,0x21,0xa1,0x61,0xe1,0x11,0x91, 0x51,0xd1,0x31,0xb1,0x71,0xf1,
0x09,0x89,0x49,0xc9,0x29,0xa9,0x69,0xe9,0x19,0x99, 0x59,0xd9,0x39,0xb9,0x79,0xf9,
0x05,0x85,0x45,0xc5,0x25,0xa5,0x65,0xe5,0x15,0x95, 0x55,0xd5,0x35,0xb5,0x75,0xf5,
0x0d,0x8d,0x4d,0xcd,0x2d,0xad,0x6d,0xed,0x1d,0x9d, 0x5d,0xdd,0x3d,0xbd,0x7d,0xfd,
0x03,0x83,0x43,0xc3,0x23,0xa3,0x63,0xe3,0x13,0x93, 0x53,0xd3,0x33,0xb3,0x73,0xf3,
0x0b,0x8b,0x4b,0xcb,0x2b,0xab,0x6b,0xeb,0x1b,0x9b, 0x5b,0xdb,0x3b,0xbb,0x7b,0xfb,
0x07,0x87,0x47,0xc7,0x27,0xa7,0x67,0xe7,0x17,0x97, 0x57,0xd7,0x37,0xb7,0x77,0xf7,
0x0f,0x8f,0x4f,0xcf,0x2f,0xaf,0x6f,0xef,0x1f,0x9f, 0x5f,0xdf,0x3f,0xbf,0x7f,0xff
};

/*
*
* this function is only used internally when decrypting title key
*
*/
static void css_titlekey(byte *key, byte *im, byte invert)
{
unsigned int lfsr1_lo,lfsr1_hi,lfsr0,combined;
byte o_lfsr0, o_lfsr1;
byte k[5];
int i;

lfsr1_lo = im[0] | 0x100;
lfsr1_hi = im[1];

lfsr0 = ((im[4] >8)&0xff] >16)&0xff]>24)&0xff];

combined = 0;
for (i = 0; i >1;
lfsr1_lo = ((lfsr1_lo&1)>7)^(lfsr0>>10)^(lfsr0>>11)^(lfsr0>>1 9);*/
o_lfsr0 = (((((((lfsr0>>8)^lfsr0)>>1)^lfsr0)>>3)^lfsr0)>>7);
lfsr0 = (lfsr0>>8)|(o_lfsr0>= 8;
}

key[4]=k[4]^csstab1[key[4]]^key[3];
key[3]=k[3]^csstab1[key[3]]^key[2];
key[2]=k[2]^csstab1[key[2]]^key[1];
key[1]=k[1]^csstab1[key[1]]^key[0];
key[0]=k[0]^csstab1[key[0]]^key[4];

key[4]=k[4]^csstab1[key[4]]^key[3];
key[3]=k[3]^csstab1[key[3]]^key[2];
key[2]=k[2]^csstab1[key[2]]^key[1];
key[1]=k[1]^csstab1[key[1]]^key[0];
key[0]=k[0]^csstab1[key[0]];
}

/*
*
* this function decrypts a title key with the specified disk key
*
* tkey: the unobfuscated title key (XORed with BusKey)
* dkey: the unobfuscated disk key (XORed with BusKey)
* 2048 bytes in length (though only 5 bytes are needed, see below)
* pkey: array of pointers to player keys and disk key offsets
*
*
* use the result returned in tkey with css_descramble
*
*/

int css_decrypttitlekey(byte *tkey, byte *dkey, struct playkey **pkey)
{
byte test[5], pretkey[5];
int i = 0;

for (; *pkey; ++pkey, ++i) {
memcpy(pretkey, dkey + (*pkey)->offset, 5);
css_titlekey(pretkey, (*pkey)->key, 0);

memcpy(test, dkey, 5);
css_titlekey(test, pretkey, 0);

if (memcmp(test, pretkey, 5) == 0) {
fprintf(stderr, "Using Key %d\n", i+1);
break;
}
}

if (!*pkey) {
fprintf(stderr, "Shit - Need Key %d\n", i+1);
return 0;
}

css_titlekey(tkey, pretkey, 0xff);

return 1;
}

/*
*
* this function does the actual descrambling
*
* sec: encrypted sector (2048 bytes)
* key: decrypted title key obtained from css_decrypttitlekey
*
*/
void css_descramble(byte *sec,byte *key)
{
unsigned int lfsr1_lo,lfsr1_hi,lfsr0,combined;
unsigned char o_lfsr0, o_lfsr1;
unsigned char *end = sec + 0x800;
#define SALTED(i) (key[i] ^ sec[0x54 + (i)])

lfsr1_lo = SALTED(0) | 0x100;
lfsr1_hi = SALTED(1);

lfsr0 = ((SALTED(4) >8)&0xff] >16)&0xff]>24)&0xff];

sec+=0x80;
combined = 0;
while (sec != end) {
o_lfsr1 = lfsr1_bits0[lfsr1_hi] ^ lfsr1_bits1[lfsr1_lo];
lfsr1_hi = lfsr1_lo>>1;
lfsr1_lo = ((lfsr1_lo&1)>7)^(lfsr0>>10)^(lfsr0>>11)^(lfsr0>>1 9);*/
o_lfsr0 = (((((((lfsr0>>8)^lfsr0)>>1)^lfsr0)>>3)^lfsr0)>>7);
lfsr0 = (lfsr0>>8)|(o_lfsr0>= 8;
}
}


/*
* css-descramble.h
*/
#ifndef __css_descramble_h_
#define __css_descramble_h_

struct playkey {
int offset;
unsigned char key[5];
};

extern int css_decrypttitlekey(unsigned char *tkey, unsigned char *dkey, struct playkey **pkey);
extern void css_descramble(unsigned char *sec,unsigned char *key);

#endif

See how much the first admendment is :)

Re:They Run Linux, silly.

On: Xerox-Microsoft Partner

They do indeed. I know one of their engineer guys and he has told me so. They even use to run their high-end super-duper digital copiers. You really have to wonder why in the world they would switch. The users never see the operating system as it is, and Xerox copiers tend to be reliable. What benefit do they get by running NT, which, even if it was reliable, costs money and does not even make an attempt at being an embedded system?

Insurance?

On: Ikonos 1 lost in space

Do they insure against these sorts of things? If they did, some risk management guys are looking pretty god right about now...

Well in this great?

On: JPEG 2000 Specs

Sure, it all sounds great, but for web designers like me, this doen't mean a thing. Even when the specification does get released, it won't even be supported by the 5.0 browsers, let alone the older browsers (which give us enough trouble as it is!). Not only that, but this format will have to go head to head with PNG, which is now supported by browsers and has a lot of industry support (it's the official "Next Big Thing" for web graphics).

If this thing ever does get the support it needs, I'll gladly use it, but as it is, absolute vs. relative positioning give me enough headaches...

Peter

Good Riddance

On: Dilbert Hole now Closed Down

That stuff was messed up. Looks like the lawyers have have actually done a good thing for once!