Method _sendMsg

code/default/lib/noarch/tlslite/tlsrecordlayer.py:912–944

Fragment and send message through socket

(self, msg, randomizeFirstBlock=True, update_hashes=True)

        self.sock.buffer_writes = False

    def _sendMsg(self, msg, randomizeFirstBlock=True, update_hashes=True):
        """Fragment and send message through socket"""
        #Whenever we're connected and asked to send an app data message,
        #we first send the first byte of the message.  This prevents
        #an attacker from launching a chosen-plaintext attack based on
        #knowing the next IV (a la BEAST).
        if randomizeFirstBlock and self.version <= (3, 1) \
                and self._recordLayer.isCBCMode() \
                and msg.contentType == ContentType.application_data:
            msgFirstByte = msg.splitFirstByte()
            for result in self._sendMsgThroughSocket(msgFirstByte):
                yield result
            if len(msg.write()) == 0:
                return

        buf = msg.write()
        contentType = msg.contentType
        #Update handshake hashes
        if update_hashes and contentType == ContentType.handshake:
            self._handshake_hash.update(buf)

        #Fragment big messages
        while len(buf) > self.recordSize:
            newB = buf[:self.recordSize]
            buf = buf[self.recordSize:]

            msgFragment = Message(contentType, newB)
            for result in self._sendMsgThroughSocket(msgFragment):
                yield result

        msgFragment = Message(contentType, buf)
        for result in self._sendMsgThroughSocket(msgFragment):
            yield result

    def _queue_message(self, msg):
        """Just queue message for sending, for record layer coalescing."""