proxmark3/client/src/loclass/cipherutils.c
2022-02-15 16:01:23 +01:00

253 lines
7.7 KiB
C

//-----------------------------------------------------------------------------
// Borrowed initially from https://github.com/holiman/loclass
// Copyright (C) 2014 Martin Holst Swende
// Copyright (C) Proxmark3 contributors. See AUTHORS.md for details.
//
// This program 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 3 of the License, or
// (at your option) any later version.
//
// This program 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.
//
// See LICENSE.txt for the text of the license.
//-----------------------------------------------------------------------------
// 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.
//-----------------------------------------------------------------------------
// It is a reconstruction 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".
//-----------------------------------------------------------------------------
#include "cipherutils.h"
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "util.h" // sprint_hex
#include "commonutil.h" // ARRAYLEN
#include "fileutils.h"
/**
*
* @brief Return and remove the first bit (x0) in the stream : <x0 x1 x2 x3 ... xn >
* @param stream
* @return
*/
bool headBit(BitstreamIn_t *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_t *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_t *stream, bool bit) {
int bytepos = stream->position >> 3; // divide by 8
int bitpos = stream->position & 7;
*(stream->buffer + bytepos) |= (bit) << (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_t *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_t *stream) {
return stream->numbits - stream->position;
}
/**
* @brief numBits
* @param stream
* @return Number of bits stored in stream
*/
/*
static int numBits(BitstreamOut_t *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;
}
void reverse_arraybytes(uint8_t *arr, size_t len) {
uint8_t i;
for (i = 0; i < len ; i++) {
arr[i] = reflect8(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] = reflect8(arr[i]);
}
}
void printarr(const char *name, uint8_t *arr, int len) {
if (name == NULL || arr == NULL) return;
int cx, i;
size_t outsize = 40 + strlen(name) + len * 5;
char *output = calloc(outsize, sizeof(char));
cx = snprintf(output, outsize, "uint8_t %s[] = {", name);
for (i = 0; i < len; i++) {
if (cx < outsize)
cx += snprintf(output + cx, outsize - cx, "0x%02x,", *(arr + i)); //5 bytes per byte
}
if (cx < outsize)
snprintf(output + cx, outsize - cx, "};");
PrintAndLogEx(INFO, output);
free(output);
}
void printarr_human_readable(const char *title, uint8_t *arr, int len) {
if (arr == NULL) return;
int cx = 0, i;
size_t outsize = 100 + strlen(title) + (len * 4);
char *output = calloc(outsize, sizeof(char));
PrintAndLogEx(INFO, "%s", title);
for (i = 0; i < len; i++) {
if (i % 16 == 0) {
if (i == 0) {
if (cx < outsize)
cx += snprintf(output + cx, outsize - cx, "%02x| ", i);
} else {
if (cx < outsize)
cx += snprintf(output + cx, outsize - cx, "\n%02x| ", i);
}
}
if (cx < outsize)
cx += snprintf(output + cx, outsize - cx, "%02x ", *(arr + i));
}
PrintAndLogEx(INFO, output);
free(output);
}
//-----------------------------
// Code for testing below
//-----------------------------
#ifndef ON_DEVICE
static int testBitStream(void) {
uint8_t input [] = {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF};
uint8_t output [] = {0, 0, 0, 0, 0, 0, 0, 0};
BitstreamIn_t in = { input, sizeof(input) * 8, 0};
BitstreamOut_t 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) {
PrintAndLogEx(SUCCESS, " Bitstream test 1 (%s)", _GREEN_("ok"));
} else {
PrintAndLogEx(FAILED, " Bitstream test 1 (%s)", _RED_("failed"));
uint8_t i;
for (i = 0 ; i < ARRAYLEN(input) ; i++) {
PrintAndLogEx(NORMAL, " IN %02x, OUT %02x", input[i], output[i]);
}
return PM3_ESOFT;
}
return PM3_SUCCESS;
}
static int testReversedBitstream(void) {
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_t in = { input, sizeof(input) * 8, 0};
BitstreamOut_t out = { output, 0, 0};
BitstreamIn_t reversed_in = { reverse, sizeof(input) * 8, 0};
BitstreamOut_t 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) {
PrintAndLogEx(SUCCESS, " Bitstream test 2 (%s)", _GREEN_("ok"));
} else {
PrintAndLogEx(FAILED, " Bitstream test 2 (%s)", _RED_("failed"));
uint8_t i;
for (i = 0 ; i < ARRAYLEN(input) ; i++) {
PrintAndLogEx(NORMAL, " IN %02x, MIDDLE: %02x, OUT %02x", input[i], reverse[i], output[i]);
}
return PM3_ESOFT;
}
return PM3_SUCCESS;
}
int testCipherUtils(void) {
PrintAndLogEx(INFO, "Testing some internals...");
int retval = testBitStream();
if (retval == PM3_SUCCESS)
retval = testReversedBitstream();
return retval;
}
#endif