Fix hex_to_bytes and add it to common utils.

[platform/upstream/cryptsetup.git] / lib / utils_crypt.c

diff --git a/lib/utils_crypt.c b/lib/utils_crypt.c
index 1fe9555..dd7496a 100644 (file)
--- a/lib/utils_crypt.c
+++ b/lib/utils_crypt.c
@@ -397,3 +397,29 @@ out_err:
                crypt_safe_free(pass);
        return r;
 }
+
+ssize_t crypt_hex_to_bytes(const char *hex, char **result, int safe_alloc)
+{
+       char buf[3] = "xx\0", *endp, *bytes;
+       size_t i, len;
+
+       len = strlen(hex);
+       if (len % 2)
+               return -EINVAL;
+       len /= 2;
+
+       bytes = safe_alloc ? crypt_safe_alloc(len) : malloc(len);
+       if (!bytes)
+               return -ENOMEM;
+
+       for (i = 0; i < len; i++) {
+               memcpy(buf, &hex[i * 2], 2);
+               bytes[i] = strtoul(buf, &endp, 16);
+               if (endp != &buf[2]) {
+                       safe_alloc ? crypt_safe_free(bytes) : free(bytes);
+                       return -EINVAL;
+               }
+       }
+       *result = bytes;
+       return i;
+}