void readBytes(final byte[] buffer, final int position) throws NTLMEngineException {
            if (messageContents.length < position + buffer.length) {
                throw new NTLMEngineException("NTLM: Message too short");
            }
            System.arraycopy(messageContents, position, buffer, 0, buffer.length);
        }
Read a bunch of bytes from a position in the message buffer
httpclient5/src/main/java/org/apache/hc/client5/http/impl/auth/NTLMEngineImpl.java