+
+/**
+ * Convert a block of binary data to HEX.
+ *
+ * @param data binary data to convert
+ * @param data_size number of bytes in @a data
+ * @return HEX string (lower case)
+ */
+char *
+GNUNET_DNSPARSER_bin_to_hex (const void *data,
+ size_t data_size)
+{
+ char *ret;
+ size_t off;
+ const uint8_t *idata;
+
+ idata = data;
+ ret = GNUNET_malloc (data_size * 2 + 1);
+ for (off = 0; off < data_size; off++)
+ sprintf (&ret[off * 2],
+ "%x",
+ idata[off]);
+ return ret;
+}
+
+
+/**
+ * Convert a HEX string to block of binary data.
+ *
+ * @param hex HEX string to convert (may contain mixed case)
+ * @param data where to write result, must be
+ * at least `strlen(hex)/2` bytes long
+ * @return number of bytes written to data
+ */
+size_t
+GNUNET_DNSPARSER_hex_to_bin (const char *hex,
+ void *data)
+{
+ size_t data_size;
+ size_t off;
+ uint8_t *idata;
+ unsigned int h;
+ char in[3];
+
+ data_size = strlen (hex) / 2;
+ idata = data;
+ in[2] = '\0';
+ for (off = 0; off < data_size; off++)
+ {
+ in[0] = tolower ((int) hex[off * 2]);
+ in[1] = tolower ((int) hex[off * 2 + 1]);
+ if (1 != sscanf (in, "%x", &h))
+ return off;
+ idata[off] = (uint8_t) h;
+ }
+ return off;
+}
+
+