task4.c


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#include "lib.h"

void main() {
	/** read the file */
	FILE *fp;
	int bytes_read;
	int malloc_size = 62;
	int line_number = 0;
	int j;
	char *string = malloc(malloc_size);
	char *string2 = malloc(malloc_size);
	char *cleartext = malloc(malloc_size);
	char *keys = malloc(255);
	char single_key;
	int length;

	fp = fopen("4.txt", "r");

	if (fp == NULL) {
		printf("Error open file\n");
		exit(1);
	}
	
	while (fscanf(fp, "%61c", string) != EOF) {
		j = decode_hex_string(string, string2);
		length = brute_force_single_byte_xor(string2, j, keys);
		if (length > 0) {
			printf("line %i:\n", line_number);
			for(j=0;j<length;j++) {
				single_key = keys[j];
				xor_string(string2, &single_key, cleartext);
				printf("%s\n", cleartext);
			}
		}
		line_number++;
	}

	fclose(fp);

}