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added support for multi-idat

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2021-10-27 21:30:41 -04:00
parent 1d3c6d3212
commit e0c035a4cf
2 changed files with 64 additions and 27 deletions
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88
cmd/crc.c
View File

@@ -70,12 +70,11 @@ int update_file_crc(unsigned char *addr, unsigned long offset , unsigned int crc
return 0;
}
static void random_window_bit_change(unsigned char *data, int width, int rounds, int color_range, size_t length) {
static void random_window_bit_change(unsigned char *data, int width, int rounds, int color_range, size_t length, size_t offset) {
size_t random_num = 0;
for (int i = 0; i < rounds; i++) {
random_num = randombytes_uniform(length);
do {
random_num = randombytes_uniform(length);
random_num = randombytes_uniform(length) + offset;
} while((random_num % ((width * color_range) + 1)) == 0);
@@ -88,7 +87,7 @@ static void random_window_bit_change(unsigned char *data, int width, int rounds,
return;
}
static int verify_crc_chunks(unsigned char *data, size_t data_length, int crc_depth, unsigned int max_data_length) {
static int verify_crc_chunks(unsigned char *data, size_t data_length, int crc_depth, unsigned int max_data_length, char message, size_t iteration) {
unsigned char* testing_chunk;
unsigned int crc_check = 0;
unsigned int test_data_length = 0;
@@ -111,15 +110,16 @@ static int verify_crc_chunks(unsigned char *data, size_t data_length, int crc_de
testing_chunk[2] = 0x41;
testing_chunk[3] = 0x54;
for(int j = 0; j < test_data_length; j++) {
testing_chunk[j+4] = data[(test_data_length*rounds)+j];
testing_chunk[j+4] = data[(test_data_length*rounds)+j+(MAX_WINDOW_SIZE*iteration)];
}
crc_check_length = test_data_length+4;
crc_check = crc(testing_chunk, crc_check_length);
if ((crc_check >> (8*3)) != 10 ) {
if ((crc_check >> (8*3)) != message ) {
free(testing_chunk);
return 1;
}
printf("FOUND: %c\n", message);
// Used as an alternative to i
// Since i needs to be changed it max data length is met
rounds++;
@@ -128,16 +128,16 @@ static int verify_crc_chunks(unsigned char *data, size_t data_length, int crc_de
return 0;
}
static int crc_embed_data(unsigned char *data, unsigned int data_length, int bit_width, int color_range, unsigned int sliding_window) {
static int crc_embed_data(unsigned char *data, unsigned int data_length, int bit_width, int color_range, unsigned int sliding_window, char message, size_t offset , size_t iteration) {
unsigned char *check_data;
size_t check_data_length = 0;
random_window_bit_change(data, bit_width, 2, color_range, sliding_window);
random_window_bit_change(data, bit_width, 2, color_range, sliding_window, offset);
// Compressing data for test
zlib_compress_data(data, data_length, &check_data, &check_data_length);
int match_crc = verify_crc_chunks(check_data, check_data_length, 1, MAX_IDAT_SIZE);
int match_crc = verify_crc_chunks(check_data, check_data_length, 1, MAX_IDAT_SIZE, message, iteration);
if(match_crc == 0) {
printf("COM SIZE: %zu\n", check_data_length);
@@ -151,6 +151,7 @@ static int crc_embed_data(unsigned char *data, unsigned int data_length, int bit
void *random_data_change_thread_call(void *w) {
struct EMBED_THREAD_STRUCT *data = w;
unsigned char* temp_color_data = calloc(data->uncom_data_len, sizeof(unsigned char));
char cur_message;
int searching = 1;
do {
// Creating temporary data set
@@ -158,21 +159,24 @@ void *random_data_change_thread_call(void *w) {
// Look into testing these values more
if(data->uncom_data_len > 800000) {
data->data_len = 90000;
data->data_len = 90000 + (90000 * data->cur_iteration);
} else {
data->data_len = data->uncom_data_len;
}
if(data->uncom_data_len > 16000) {
data->win_size = 9000;
data->win_size = 9000 + (9000 * data->cur_iteration);
} else {
data->win_size = data->uncom_data_len;
}
searching = crc_embed_data(temp_color_data, data->data_len, data->width, data->color_range, data->win_size);
cur_message = data->message[data->cur_iteration];
searching = crc_embed_data(temp_color_data, data->data_len, data->width, data->color_range, data->win_size, cur_message, data->cur_offset, data->cur_iteration);
pthread_mutex_lock(&data->mutex_lock);
if (searching == 0 && *data->searching == 1) {
*data->searching = searching;
printf("CUR MESSAGE: %c\n", cur_message);
for(size_t i = 0; i < data->uncom_data_len; i++) {
if (temp_color_data[i] != data->data[i]) {
printf("LEN: %zu\nDIFF: %zu\nNEW: %02X\nOLD: %02X\n", data->uncom_data_len, i, temp_color_data[i], data->data[i]);
@@ -189,13 +193,32 @@ void *random_data_change_thread_call(void *w) {
pthread_exit(0);
}
void random_data_change(unsigned char *color_data, unsigned char *width, size_t length) {
size_t generate_offset(unsigned char *data, size_t data_len, size_t iteration) {
unsigned char *com_data_buff = NULL;
unsigned char *uncom_data_buff = NULL;
size_t com_data_size = 0;
size_t uncom_data_size = 0;
printf("Gen Offset\n");
zlib_compress_data(data, data_len, &com_data_buff, &com_data_size);
zlib_decompress_data(com_data_buff, (MAX_WINDOW_SIZE * (iteration+1)), &uncom_data_buff, &uncom_data_size);
printf("NEW SIZE: %zu\n", uncom_data_size);
free(com_data_buff);
free(uncom_data_buff);
return uncom_data_size;
}
void random_data_change(unsigned char *color_data, unsigned char *width, size_t length, char *message) {
int searching = 1;
int core_count = 1;
unsigned int sliding_window = 0;
unsigned int compress_data_length = 0;
// Needs to be turned into a variable
int color_range = 3;
int waiting = 0;
// Union for width type cast
union {
uint32_t width_int;
@@ -210,25 +233,36 @@ void random_data_change(unsigned char *color_data, unsigned char *width, size_t
return;
}
t_data->searching = &searching;
t_data->message = message;
t_data->data = color_data;
t_data->data_len = compress_data_length;
t_data->uncom_data_len = length;
t_data->cur_offset = 0;
t_data->width = be32toh(w.width_int);
t_data->color_range = color_range;
t_data->win_size = sliding_window;
pthread_t tid;
t_data->thread_id = tid;
for(int i = 0; i < core_count; i++) {
pthread_create(&tid, NULL, random_data_change_thread_call, t_data);
}
// Waiting for all threads to complete
int waiting = 0;
do {
pthread_join(tid, NULL);
waiting++;
} while(waiting!=core_count);
pthread_mutex_destroy(&t_data->mutex_lock);
for(int j = 0; j < strlen(message); j++) {
// Setting Iteration bit and searching
t_data->cur_iteration = j;
*t_data->searching = 1;
for(int i = 0; i < core_count; i++) {
pthread_create(&tid, NULL, random_data_change_thread_call, t_data);
}
// Waiting for all threads to complete
waiting = 0;
do {
pthread_join(tid, NULL);
waiting++;
} while(waiting!=core_count);
pthread_mutex_destroy(&t_data->mutex_lock);
// Only generate new offset if not last char in message
if(j != (strlen(message) - 1)) {
t_data->cur_offset = generate_offset(color_data, t_data->uncom_data_len, j);
}
}
return;
}
@@ -342,7 +376,7 @@ int change_idat_content(unsigned char *addr, struct PNG_FILE_STRUCT *png_file, c
if(accuracy > 2) {
printf("Notice, this could take a long time...");
}
if(total_idat(addr) < strlen((char*)message)) {
if(total_idat(addr) < strlen(message)) {
printf("Warning, message exceeds IDAT amount\n");
exit(EXIT_FAILURE);
}
@@ -361,7 +395,7 @@ int change_idat_content(unsigned char *addr, struct PNG_FILE_STRUCT *png_file, c
printf("ORIG UNCOM LEN: %zu\n", uncom_data_size);
// Start data testing
random_data_change(uncom_data_buff, png_file->png_start_data.file_width, uncom_data_size);
random_data_change(uncom_data_buff, png_file->png_start_data.file_width, uncom_data_size, message);
//return 0;
// Compress Data
@@ -410,7 +444,7 @@ int main(int argc, char **argv) {
{"outfile", required_argument, NULL, 'o'},
{"message", required_argument, NULL, 'm'},
{"compress", no_argument, NULL, 'c'},
{"uncompress", no_argument, NULL, 'h'},
{"uncompress", no_argument, NULL, 'u'},
{0, 0, 0, 0}
};
@@ -490,7 +524,7 @@ int main(int argc, char **argv) {
unsigned char* idat_data = populate_idat_array(file_data, offset, &idat_byte_length);
for(int i = 0; i < idat_byte_length; i++) {
printf("%02X ", idat_data[i]);
//printf("%02X ", idat_data[i]);
}
printf("\nDecompressed Data:\n\n");
// Decompressing data

3
include/crc_util.h
View File

@@ -40,9 +40,12 @@ struct EMBED_THREAD_STRUCT {
unsigned char *data;
unsigned int data_len;
size_t uncom_data_len;
size_t cur_offset;
size_t cur_iteration;
int width;
int color_range;
unsigned int win_size;
char *message;
};
extern const long png_signature[8];