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multi idat write support

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Pin
2021-10-24 22:50:42 -04:00
parent 83dda0ef00
commit dff9e4aea8
2 changed files with 102 additions and 57 deletions
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157
cmd/crc.c
View File

@@ -13,6 +13,9 @@
#include "crc.h"
#include "compress_util.h"
#define MAX_IDAT_SIZE 16384
//#define MAX_IDAT_SIZE 8192
const long idat_signature = 1229209940;
const long iend_signature = 1229278788;
@@ -87,36 +90,43 @@ static int verify_crc_chunks(unsigned char *data, size_t data_length, int crc_de
unsigned char* testing_chunk;
unsigned int crc_check = 0;
unsigned int test_data_length = 0;
unsigned int crc_check_length;
int rounds = 0;
for(int i = 0; i < crc_depth; i++) {
if((max_data_length * (i+1)) > data_length) {
test_data_length = (data_length - (max_data_length * i));
testing_chunk = calloc(test_data_length+4, sizeof(unsigned char));
// If this is met we need to stop verification
i = crc_depth;
} else {
test_data_length = max_data_length;
testing_chunk = calloc(test_data_length+4, sizeof(unsigned char));
}
// Setting first chunk to IDAT
testing_chunk[0] = 0x49;
testing_chunk[1] = 0x44;
testing_chunk[2] = 0x41;
testing_chunk[3] = 0x54;
for(int j = 0; j < test_data_length; j++) {
testing_chunk[j+4] = data[(max_data_length*i)+j];
testing_chunk[j+4] = data[(test_data_length*rounds)+j];
}
crc_check_length = test_data_length+4;
crc_check = crc(testing_chunk, crc_check_length);
if(i == 1) {
printf("ATTEMPT: %08X\n", crc_check);
}
crc_check = crc(testing_chunk, test_data_length);
if(i == 2) {
printf("THIRD: %08X\n", crc_check);
} else if(i == 1) {
printf("SECOND: %08X\n", crc_check);
}
if ((crc_check >> (8*3)) != 10 ) {
free(testing_chunk);
return 1;
}
// Used as an alternative to i
// Since i needs to be changed it max data length is met
rounds++;
}
free(testing_chunk);
printf("FOUND: %08X\n", crc_check);
return 0;
}
@@ -129,9 +139,10 @@ static int crc_embed_data(unsigned char *data, unsigned int data_length, int bit
// 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, 3, 8192);
int match_crc = verify_crc_chunks(check_data, check_data_length, 1, MAX_IDAT_SIZE);
if(match_crc == 0) {
printf("COM SIZE: %zu\n", check_data_length);
free(check_data);
return 0;
}
@@ -147,8 +158,9 @@ void *random_data_change_thread_call(void *w) {
// Creating temporary data set
memcpy(temp_color_data, data->data, data->uncom_data_len);
// Look into testing these values more
if(data->uncom_data_len > 800000) {
data->data_len = 150000;
data->data_len = 90000;
} else {
data->data_len = data->uncom_data_len;
}
@@ -160,22 +172,23 @@ void *random_data_change_thread_call(void *w) {
searching = crc_embed_data(temp_color_data, data->data_len, data->width, data->color_range, data->win_size);
if (searching == 0) {
pthread_mutex_lock(data->mutex_lock);
//pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
pthread_mutex_lock(&data->mutex_lock);
if (searching == 0 && *data->searching == 1) {
*data->searching = searching;
memcpy(data->data, temp_color_data, data->uncom_data_len);
//pthread_cancel(data->thread_id);
pthread_mutex_unlock(data->mutex_lock);
pthread_mutex_unlock(&data->mutex_lock);
break;
}
pthread_mutex_unlock(&data->mutex_lock);
} while(*data->searching == 1);
free(temp_color_data);
return NULL;
pthread_exit(0);
}
void random_data_change(unsigned char *color_data, unsigned char *width, size_t length) {
int searching = 1;
int core_count = 16;
unsigned int sliding_window = 0;
unsigned int compress_data_length = 0;
// Needs to be turned into a variable
@@ -187,24 +200,31 @@ void random_data_change(unsigned char *color_data, unsigned char *width, size_t
}w;
memcpy(w.width_array, width, 4);
// Temp data array for crc testing
//unsigned char* temp_color_data = calloc(length, sizeof(unsigned char));
struct EMBED_THREAD_STRUCT *t_data = malloc(sizeof(struct EMBED_THREAD_STRUCT));
//int num_threads = 1;
struct EMBED_THREAD_STRUCT t_data;
t_data.searching = &searching;
t_data.data = color_data;
t_data.data_len = compress_data_length;
t_data.uncom_data_len = length;
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 < 28; i++) {
pthread_create(&tid, NULL, random_data_change_thread_call, &t_data);
if(pthread_mutex_init(&t_data->mutex_lock, NULL) != 0) {
printf("Mutex Lock Error\n");
return;
}
pthread_join(tid, NULL);
t_data->searching = &searching;
t_data->data = color_data;
t_data->data_len = compress_data_length;
t_data->uncom_data_len = length;
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);
return;
}
@@ -227,32 +247,57 @@ void build_png_file(struct PNG_FILE_STRUCT *png_file, char *out_file_name) {
for(int i = 0; i < sizeof(start_data.data); i++) {
fputc(start_data.data[i], fp);
}
// IDAT Data
for(int i = 0; i < 4; i++) {
fputc(png_file->png_idat_data.idat_length[i], fp);
}
for(int i = 0; i < 4; i++) {
fputc(png_file->png_idat_data.idat_header[i], fp);
}
for(int i = 0; i < be32toh(png_file->png_idat_data.idat_data_length); i++) {
fputc(png_file->png_idat_data.idat_data[i], fp);
}
// Generating CRC
unsigned char full_data[be32toh(png_file->png_idat_data.idat_data_length)+4];
for(int i = 0; i < 4; i++) {
full_data[i] = png_file->png_idat_data.idat_header[i];
}
for(int i = 0; i < be32toh(png_file->png_idat_data.idat_data_length); i++) {
full_data[i+4] = png_file->png_idat_data.idat_data[i];
}
unsigned int int_crc = crc(full_data, be32toh(png_file->png_idat_data.idat_data_length));
unsigned char new_crc[4];
// Generating IDAT CHUNKS
int idat_loop = 0;
uint32_t current_len = 0;
do {
// Setting IDAT length chunk variable
if ((be32toh(png_file->png_idat_data.idat_data_length)-(MAX_IDAT_SIZE*idat_loop)) > MAX_IDAT_SIZE) {
current_len = MAX_IDAT_SIZE;
} else {
current_len = (be32toh(png_file->png_idat_data.idat_data_length)-(MAX_IDAT_SIZE*idat_loop));
}
// IDAT LENGTH WRITE
for(int i = 0; i < 4; i++) {
//fputc(png_file->png_idat_data.idat_length[i], fp);
fputc(current_len >> (8*(3-i)), fp);
}
// IDAT HEADER WRITE
for(int i = 0; i < 4; i++) {
fputc(png_file->png_idat_data.idat_header[i], fp);
}
// IDAT DATA WRITE
//for(int i = 0; i < be32toh(png_file->png_idat_data.idat_data_length); i++) {
for(int i = 0; i < current_len; i++) {
fputc(png_file->png_idat_data.idat_data[i+(MAX_IDAT_SIZE*idat_loop)], fp);
}
// Generating CRC
//unsigned char *full_data = malloc(be32toh(png_file->png_idat_data.idat_data_length)+4);
unsigned char *full_data = malloc(current_len+4);
for(int i = 0; i < 4; i++) {
full_data[i] = png_file->png_idat_data.idat_header[i];
}
for(int i = 0; i < current_len; i++) {
full_data[i+4] = png_file->png_idat_data.idat_data[i+(MAX_IDAT_SIZE*idat_loop)];
}
unsigned int int_crc = crc(full_data, current_len+4);
unsigned char new_crc[4];
// IDAT CRC WRITE
for(int i = 0; i < 4; i++) {
new_crc[i] = int_crc >> (8*(3-i)) & 0xFF;
fputc(new_crc[i], fp);
}
// Adding to loop count
printf("Loop: %d\n", idat_loop);
idat_loop++;
} while(idat_loop < (be32toh(png_file->png_idat_data.idat_data_length) / MAX_IDAT_SIZE));
for(int i = 0; i < 4; i++) {
new_crc[i] = int_crc >> (8*(3-i)) & 0xFF;
fputc(new_crc[i], fp);
}
// IEND Data
unsigned char IEND_DATA[12] = { 0x00, 0x00, 0x00, 0x00, 0x49, 0x45, 0x4E, 0x44, 0xAE, 0x42, 0x60, 0x82};
for(int i = 0; i < 12; i++) {

2
include/crc_util.h
View File

@@ -34,7 +34,7 @@ struct PNG_FILE_STRUCT {
};
struct EMBED_THREAD_STRUCT {
pthread_mutex_t *mutex_lock;
pthread_mutex_t mutex_lock;
pthread_t thread_id;
int *searching;
unsigned char *data;