hex2val
key[i] = (key[i] << 4) | hex2val(*p);
hw_addr[i] = (hex2val(na[2 * i + 0]) * 16 +
hex2val(na[2 * i + 1]));
hw_addr[i] = (hex2val(na[2 * i + 0]) * 16 +
hex2val(na[2 * i + 1]));