#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <stdbool.h>
#include <stdint.h>
#include <unistd.h>
#include <sys/stat.h>
static char default_pattern[] = "12345678";
+static int is_hex_pattern;
int xor_data(uint8_t *data, size_t len, const uint8_t *pattern, int p_len, int p_off)
void usage(void)
{
- fprintf(stderr, "Usage: xorimage [-i infile] [-o outfile] [-p <pattern>]\n");
+ fprintf(stderr, "Usage: xorimage [-i infile] [-o outfile] [-p <pattern>] [-x]\n");
exit(EXIT_FAILURE);
}
char *ifn = NULL;
char *ofn = NULL;
const char *pattern = default_pattern;
+ char hex_pattern[128];
+ unsigned int hex_buf;
int c;
int v0, v1, v2;
size_t n;
int p_len, p_off = 0;
- while ((c = getopt(argc, argv, "i:o:p:h")) != -1) {
+ while ((c = getopt(argc, argv, "i:o:p:xh")) != -1) {
switch (c) {
case 'i':
ifn = optarg;
case 'p':
pattern = optarg;
break;
+ case 'x':
+ is_hex_pattern = true;
+ break;
case 'h':
default:
usage();
usage();
}
+ if (is_hex_pattern) {
+ int i;
+
+ if ((p_len / 2) > sizeof(hex_pattern)) {
+ fprintf(stderr, "provided hex pattern is too long\n");
+ usage();
+ }
+
+ if (p_len % 2 != 0) {
+ fprintf(stderr, "the number of characters (hex) is incorrect\n");
+ usage();
+ }
+
+ for (i = 0; i < (p_len / 2); i++) {
+ if (sscanf(pattern + (i * 2), "%2x", &hex_buf) < 0) {
+ fprintf(stderr, "invalid hex digit around %d\n", i * 2);
+ usage();
+ }
+ hex_pattern[i] = (char)hex_buf;
+ }
+ }
while ((n = fread(buf, 1, sizeof(buf), in)) > 0) {
if (n < sizeof(buf)) {
}
}
- p_off = xor_data(buf, n, pattern, p_len, p_off);
+ if (is_hex_pattern) {
+ p_off = xor_data(buf, n, hex_pattern, (p_len / 2),
+ p_off);
+ } else {
+ p_off = xor_data(buf, n, pattern, p_len, p_off);
+ }
if (!fwrite(buf, n, 1, out)) {
FWRITE_ERROR: