[proxmark3-svn] / client / loclass / cipherutils.c

/*****************************************************************************
 * WARNING
 *
 * THIS CODE IS CREATED FOR EXPERIMENTATION AND EDUCATIONAL USE ONLY. 
 * 
 * USAGE OF THIS CODE IN OTHER WAYS MAY INFRINGE UPON THE INTELLECTUAL 
 * PROPERTY OF OTHER PARTIES, SUCH AS INSIDE SECURE AND HID GLOBAL, 
 * AND MAY EXPOSE YOU TO AN INFRINGEMENT ACTION FROM THOSE PARTIES. 
 * 
 * THIS CODE SHOULD NEVER BE USED TO INFRINGE PATENTS OR INTELLECTUAL PROPERTY RIGHTS. 
 *
 *****************************************************************************
 *
 * This file is part of loclass. It is a reconstructon of the cipher engine
 * used in iClass, and RFID techology.
 *
 * The implementation is based on the work performed by
 * Flavio D. Garcia, Gerhard de Koning Gans, Roel Verdult and
 * Milosch Meriac in the paper "Dismantling IClass".
 *
 * Copyright (C) 2014 Martin Holst Swende
 *
 * This is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * This file 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 loclass.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * 
 * 
 ****************************************************************************/

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "fileutils.h"
#include "cipherutils.h"
/**
 *
 * @brief Return and remove the first bit (x0) in the stream : <x0 x1 x2 x3 ... xn >
 * @param stream
 * @return
 */
bool headBit( BitstreamIn *stream)
{
	int bytepos = stream->position >> 3; // divide by 8
	int bitpos = (stream->position++) & 7; // mask out 00000111
	return (*(stream->buffer + bytepos) >> (7-bitpos)) & 1;
}
/**
 * @brief Return and remove the last bit (xn) in the stream: <x0 x1 x2 ... xn>
 * @param stream
 * @return
 */
bool tailBit( BitstreamIn *stream)
{
	int bitpos = stream->numbits -1 - (stream->position++);

	int bytepos= bitpos >> 3;
	bitpos &= 7;
	return (*(stream->buffer + bytepos) >> (7-bitpos)) & 1;
}
/**
 * @brief Pushes bit onto the stream
 * @param stream
 * @param bit
 */
void pushBit( BitstreamOut* stream, bool bit)
{
	int bytepos = stream->position >> 3; // divide by 8
	int bitpos = stream->position & 7;
	*(stream->buffer+bytepos) |= (bit & 1) <<  (7 - bitpos);
	stream->position++;
	stream->numbits++;
}

/**
 * @brief Pushes the lower six bits onto the stream
 * as b0 b1 b2 b3 b4 b5 b6
 * @param stream
 * @param bits
 */
void push6bits( BitstreamOut* stream, uint8_t bits)
{
	pushBit(stream, bits & 0x20);
	pushBit(stream, bits & 0x10);
	pushBit(stream, bits & 0x08);
	pushBit(stream, bits & 0x04);
	pushBit(stream, bits & 0x02);
	pushBit(stream, bits & 0x01);
}

/**
 * @brief bitsLeft
 * @param stream
 * @return number of bits left in stream
 */
int bitsLeft( BitstreamIn *stream)
{
	return stream->numbits - stream->position;
}
/**
 * @brief numBits
 * @param stream
 * @return Number of bits stored in stream
 */
int numBits(BitstreamOut *stream)
{
	return stream->numbits;
}

void x_num_to_bytes(uint64_t n, size_t len, uint8_t* dest)
{
	while (len--) {
		dest[len] = (uint8_t) n;
		n >>= 8;
	}
}

uint64_t x_bytes_to_num(uint8_t* src, size_t len)
{
	uint64_t num = 0;
	while (len--)
	{
		num = (num << 8) | (*src);
		src++;
	}
	return num;
}
uint8_t reversebytes(uint8_t b) {
	b = (b & 0xF0) >> 4 | (b & 0x0F) << 4;
	b = (b & 0xCC) >> 2 | (b & 0x33) << 2;
	b = (b & 0xAA) >> 1 | (b & 0x55) << 1;
   return b;
}
void reverse_arraybytes(uint8_t* arr, size_t len)
{
	uint8_t i;
	for( i =0; i< len ; i++)
	{
		arr[i] = reversebytes(arr[i]);
	}
}
void reverse_arraycopy(uint8_t* arr, uint8_t* dest, size_t len)
{
	uint8_t i;
	for( i =0; i< len ; i++)
	{
		dest[i] = reversebytes(arr[i]);
	}
}

void printarr(char * name, uint8_t* arr, int len)
{
	int cx;
	size_t outsize = 40+strlen(name)+len*5;
	char* output = malloc(outsize);
	memset(output, 0,outsize);

	int i ;
	cx = snprintf(output,outsize, "uint8_t %s[] = {", name);
	for(i =0 ;  i< len ; i++)
	{
		cx += snprintf(output+cx,outsize-cx,"0x%02x,",*(arr+i));//5 bytes per byte
	}
	cx += snprintf(output+cx,outsize-cx,"};");
	prnlog(output);
}

void printvar(char * name, uint8_t* arr, int len)
{
	int cx;
	size_t outsize = 40+strlen(name)+len*2;
	char* output = malloc(outsize);
	memset(output, 0,outsize);

	int i ;
	cx = snprintf(output,outsize,"%s = ", name);
	for(i =0 ;  i< len ; i++)
	{
		cx += snprintf(output+cx,outsize-cx,"%02x",*(arr+i));//2 bytes per byte
	}

	prnlog(output);
}

void printarr_human_readable(char * title, uint8_t* arr, int len)
{
	int cx;
	size_t outsize = 100+strlen(title)+len*4;
	char* output = malloc(outsize);
	memset(output, 0,outsize);


	int i;
	cx = snprintf(output,outsize,  "\n\t%s\n", title);
	for(i =0 ;  i< len ; i++)
	{
		if(i % 16 == 0)
			cx += snprintf(output+cx,outsize-cx,"\n%02x| ", i );
		cx += snprintf(output+cx,outsize-cx, "%02x ",*(arr+i));
	}
	prnlog(output);
	free(output);
}

//-----------------------------
// Code for testing below
//-----------------------------


int testBitStream()
{
	uint8_t input [] = {0xDE,0xAD,0xBE,0xEF,0xDE,0xAD,0xBE,0xEF};
	uint8_t output [] = {0,0,0,0,0,0,0,0};
	BitstreamIn in = { input, sizeof(input) * 8,0};
	BitstreamOut out ={ output, 0,0}
					  ;
	while(bitsLeft(&in) > 0)
	{
		pushBit(&out, headBit(&in));
		//printf("Bits left: %d\n", bitsLeft(&in));
		//printf("Bits out: %d\n", numBits(&out));
	}
	if(memcmp(input, output, sizeof(input)) == 0)
	{
		prnlog("    Bitstream test 1 ok");
	}else
	{
		prnlog("    Bitstream test 1 failed");
		uint8_t i;
		for(i = 0 ; i < sizeof(input) ; i++)
		{
			prnlog("    IN %02x, OUT %02x", input[i], output[i]);
		}
		return 1;
	}
	return 0;
}

int testReversedBitstream()
{
	uint8_t input [] = {0xDE,0xAD,0xBE,0xEF,0xDE,0xAD,0xBE,0xEF};
	uint8_t reverse [] = {0,0,0,0,0,0,0,0};
	uint8_t output [] = {0,0,0,0,0,0,0,0};
	BitstreamIn in = { input, sizeof(input) * 8,0};
	BitstreamOut out ={ output, 0,0};
	BitstreamIn reversed_in ={ reverse, sizeof(input)*8,0};
	BitstreamOut reversed_out ={ reverse,0 ,0};

	while(bitsLeft(&in) > 0)
	{
		pushBit(&reversed_out, tailBit(&in));
	}
	while(bitsLeft(&reversed_in) > 0)
	{
		pushBit(&out, tailBit(&reversed_in));
	}
	if(memcmp(input, output, sizeof(input)) == 0)
	{
		prnlog("    Bitstream test 2 ok");
	}else
	{
		prnlog("    Bitstream test 2 failed");
		uint8_t i;
		for(i = 0 ; i < sizeof(input) ; i++)
		{
			prnlog("    IN %02x, MIDDLE: %02x, OUT %02x", input[i],reverse[i], output[i]);
		}
		return 1;
	}
	return 0;
}


int testCipherUtils(void)
{
	prnlog("[+] Testing some internals...");
	int retval = 0;
	retval |= testBitStream();
	retval |= testReversedBitstream();
	return retval;
}
Commit	Line	Data
a66fca86	1	/*****************************************************************************
d60418a0 MHS	2	* WARNING
	3	*
	4	* THIS CODE IS CREATED FOR EXPERIMENTATION AND EDUCATIONAL USE ONLY.
	5	*
	6	* USAGE OF THIS CODE IN OTHER WAYS MAY INFRINGE UPON THE INTELLECTUAL
	7	* PROPERTY OF OTHER PARTIES, SUCH AS INSIDE SECURE AND HID GLOBAL,
	8	* AND MAY EXPOSE YOU TO AN INFRINGEMENT ACTION FROM THOSE PARTIES.
	9	*
	10	* THIS CODE SHOULD NEVER BE USED TO INFRINGE PATENTS OR INTELLECTUAL PROPERTY RIGHTS.
	11	*
	12	*****************************************************************************
	13	*
	14	* This file is part of loclass. It is a reconstructon of the cipher engine
a66fca86 AD	15	* used in iClass, and RFID techology.
	16	*
	17	* The implementation is based on the work performed by
	18	* Flavio D. Garcia, Gerhard de Koning Gans, Roel Verdult and
	19	* Milosch Meriac in the paper "Dismantling IClass".
	20	*
	21	* Copyright (C) 2014 Martin Holst Swende
	22	*
	23	* This is free software: you can redistribute it and/or modify
	24	* it under the terms of the GNU General Public License version 2 as published
	25	* by the Free Software Foundation.
	26	*
	27	* This file is distributed in the hope that it will be useful,
	28	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	29	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	30	* GNU General Public License for more details.
	31	*
	32	* You should have received a copy of the GNU General Public License
d60418a0 MHS	33	* along with loclass. If not, see <http://www.gnu.org/licenses/>.
	34	*
	35	*
	36	*
a66fca86 AD	37	****************************************************************************/
a66fca86 AD	38
a66fca86 AD	39	#include <stdint.h>
	40	#include <stdio.h>
	41	#include <string.h>
3ad48540 MHS	42	#include "fileutils.h"
3ad48540 MHS	43	#include "cipherutils.h"
a66fca86 AD	44	/**
	45	*
	46	* @brief Return and remove the first bit (x0) in the stream : <x0 x1 x2 x3 ... xn >
	47	* @param stream
	48	* @return
	49	*/
	50	bool headBit( BitstreamIn *stream)
	51	{
	52	int bytepos = stream->position >> 3; // divide by 8
	53	int bitpos = (stream->position++) & 7; // mask out 00000111
	54	return (*(stream->buffer + bytepos) >> (7-bitpos)) & 1;
	55	}
	56	/**
	57	* @brief Return and remove the last bit (xn) in the stream: <x0 x1 x2 ... xn>
	58	* @param stream
	59	* @return
	60	*/
	61	bool tailBit( BitstreamIn *stream)
	62	{
	63	int bitpos = stream->numbits -1 - (stream->position++);
	64
	65	int bytepos= bitpos >> 3;
	66	bitpos &= 7;
	67	return (*(stream->buffer + bytepos) >> (7-bitpos)) & 1;
	68	}
	69	/**
	70	* @brief Pushes bit onto the stream
	71	* @param stream
	72	* @param bit
	73	*/
	74	void pushBit( BitstreamOut* stream, bool bit)
	75	{
	76	int bytepos = stream->position >> 3; // divide by 8
	77	int bitpos = stream->position & 7;
	78	*(stream->buffer+bytepos) \|= (bit & 1) << (7 - bitpos);
	79	stream->position++;
	80	stream->numbits++;
	81	}
	82
	83	/**
	84	* @brief Pushes the lower six bits onto the stream
	85	* as b0 b1 b2 b3 b4 b5 b6
	86	* @param stream
	87	* @param bits
	88	*/
	89	void push6bits( BitstreamOut* stream, uint8_t bits)
	90	{
	91	pushBit(stream, bits & 0x20);
	92	pushBit(stream, bits & 0x10);
	93	pushBit(stream, bits & 0x08);
	94	pushBit(stream, bits & 0x04);
	95	pushBit(stream, bits & 0x02);
	96	pushBit(stream, bits & 0x01);
	97	}
	98
	99	/**
	100	* @brief bitsLeft
	101	* @param stream
	102	* @return number of bits left in stream
	103	*/
	104	int bitsLeft( BitstreamIn *stream)
	105	{
	106	return stream->numbits - stream->position;
	107	}
108	/**
109	* @brief numBits
110	* @param stream
111	* @return Number of bits stored in stream
112	*/
113	int numBits(BitstreamOut *stream)
114	{
115	return stream->numbits;
116	}
117
3ad48540 MHS	118	void x_num_to_bytes(uint64_t n, size_t len, uint8_t* dest)
	119	{
	120	while (len--) {
	121	dest[len] = (uint8_t) n;
	122	n >>= 8;
	123	}
	124	}
	125
	126	uint64_t x_bytes_to_num(uint8_t* src, size_t len)
	127	{
	128	uint64_t num = 0;
	129	while (len--)
	130	{
	131	num = (num << 8) \| (*src);
	132	src++;
	133	}
	134	return num;
	135	}
a66fca86 AD	136	uint8_t reversebytes(uint8_t b) {
	137	b = (b & 0xF0) >> 4 \| (b & 0x0F) << 4;
	138	b = (b & 0xCC) >> 2 \| (b & 0x33) << 2;
	139	b = (b & 0xAA) >> 1 \| (b & 0x55) << 1;
	140	return b;
	141	}
	142	void reverse_arraybytes(uint8_t* arr, size_t len)
	143	{
	144	uint8_t i;
	145	for( i =0; i< len ; i++)
	146	{
	147	arr[i] = reversebytes(arr[i]);
	148	}
	149	}
3ad48540 MHS	150	void reverse_arraycopy(uint8_t* arr, uint8_t* dest, size_t len)
	151	{
	152	uint8_t i;
	153	for( i =0; i< len ; i++)
	154	{
	155	dest[i] = reversebytes(arr[i]);
	156	}
	157	}
	158
	159	void printarr(char * name, uint8_t* arr, int len)
	160	{
	161	int cx;
	162	size_t outsize = 40+strlen(name)+len*5;
	163	char* output = malloc(outsize);
	164	memset(output, 0,outsize);
	165
	166	int i ;
	167	cx = snprintf(output,outsize, "uint8_t %s[] = {", name);
	168	for(i =0 ; i< len ; i++)
	169	{
	170	cx += snprintf(output+cx,outsize-cx,"0x%02x,",*(arr+i));//5 bytes per byte
	171	}
	172	cx += snprintf(output+cx,outsize-cx,"};");
	173	prnlog(output);
	174	}
	175
	176	void printvar(char * name, uint8_t* arr, int len)
	177	{
	178	int cx;
	179	size_t outsize = 40+strlen(name)+len*2;
	180	char* output = malloc(outsize);
	181	memset(output, 0,outsize);
	182
	183	int i ;
	184	cx = snprintf(output,outsize,"%s = ", name);
	185	for(i =0 ; i< len ; i++)
	186	{
	187	cx += snprintf(output+cx,outsize-cx,"%02x",*(arr+i));//2 bytes per byte
	188	}
	189
	190	prnlog(output);
	191	}
	192
	193	void printarr_human_readable(char * title, uint8_t* arr, int len)
	194	{
	195	int cx;
	196	size_t outsize = 100+strlen(title)+len*4;
	197	char* output = malloc(outsize);
	198	memset(output, 0,outsize);
a66fca86 AD	199
a66fca86 AD	200
3ad48540 MHS	201	int i;
	202	cx = snprintf(output,outsize, "\n\t%s\n", title);
	203	for(i =0 ; i< len ; i++)
	204	{
	205	if(i % 16 == 0)
	206	cx += snprintf(output+cx,outsize-cx,"\n%02x\| ", i );
	207	cx += snprintf(output+cx,outsize-cx, "%02x ",*(arr+i));
	208	}
	209	prnlog(output);
ca4714cd	210	free(output);
3ad48540 MHS	211	}
3ad48540 MHS	212
a66fca86 AD	213	//-----------------------------
	214	// Code for testing below
	215	//-----------------------------
	216
	217
	218	int testBitStream()
	219	{
	220	uint8_t input [] = {0xDE,0xAD,0xBE,0xEF,0xDE,0xAD,0xBE,0xEF};
	221	uint8_t output [] = {0,0,0,0,0,0,0,0};
	222	BitstreamIn in = { input, sizeof(input) * 8,0};
	223	BitstreamOut out ={ output, 0,0}
	224	;
	225	while(bitsLeft(&in) > 0)
	226	{
	227	pushBit(&out, headBit(&in));
	228	//printf("Bits left: %d\n", bitsLeft(&in));
	229	//printf("Bits out: %d\n", numBits(&out));
	230	}
	231	if(memcmp(input, output, sizeof(input)) == 0)
	232	{
3ad48540	233	prnlog(" Bitstream test 1 ok");
a66fca86 AD	234	}else
a66fca86 AD	235	{
3ad48540	236	prnlog(" Bitstream test 1 failed");
a66fca86 AD	237	uint8_t i;
	238	for(i = 0 ; i < sizeof(input) ; i++)
	239	{
3ad48540	240	prnlog(" IN %02x, OUT %02x", input[i], output[i]);
a66fca86 AD	241	}
	242	return 1;
	243	}
	244	return 0;
	245	}
	246
	247	int testReversedBitstream()
	248	{
	249	uint8_t input [] = {0xDE,0xAD,0xBE,0xEF,0xDE,0xAD,0xBE,0xEF};
	250	uint8_t reverse [] = {0,0,0,0,0,0,0,0};
	251	uint8_t output [] = {0,0,0,0,0,0,0,0};
	252	BitstreamIn in = { input, sizeof(input) * 8,0};
	253	BitstreamOut out ={ output, 0,0};
	254	BitstreamIn reversed_in ={ reverse, sizeof(input)*8,0};
	255	BitstreamOut reversed_out ={ reverse,0 ,0};
	256
	257	while(bitsLeft(&in) > 0)
	258	{
	259	pushBit(&reversed_out, tailBit(&in));
	260	}
	261	while(bitsLeft(&reversed_in) > 0)
	262	{
	263	pushBit(&out, tailBit(&reversed_in));
	264	}
	265	if(memcmp(input, output, sizeof(input)) == 0)
	266	{
3ad48540	267	prnlog(" Bitstream test 2 ok");
a66fca86 AD	268	}else
a66fca86 AD	269	{
3ad48540	270	prnlog(" Bitstream test 2 failed");
a66fca86 AD	271	uint8_t i;
	272	for(i = 0 ; i < sizeof(input) ; i++)
	273	{
3ad48540	274	prnlog(" IN %02x, MIDDLE: %02x, OUT %02x", input[i],reverse[i], output[i]);
a66fca86 AD	275	}
	276	return 1;
	277	}
	278	return 0;
	279	}
	280
	281
	282	int testCipherUtils(void)
	283	{
3ad48540	284	prnlog("[+] Testing some internals...");
a66fca86 AD	285	int retval = 0;
	286	retval \|= testBitStream();
	287	retval \|= testReversedBitstream();
	288	return retval;
	289	}