twisted.protocols.tls.TLSMemoryBIOProtocol(ProtocolWrapper) class documentation

Part of twisted.protocols.tls View Source (View In Hierarchy)

Implements interfaces: twisted.internet.interfaces.INegotiated, twisted.internet.interfaces.ISystemHandle

TLSMemoryBIOProtocol is a protocol wrapper which uses OpenSSL via a memory BIO to encrypt bytes written to it before sending them on to the underlying transport and decrypts bytes received from the underlying transport before delivering them to the wrapped protocol.

In addition to producer events from the underlying transport, the need to wait for reads before a write can proceed means the TLSMemoryBIOProtocol may also want to pause a producer. Pause/resume events are therefore merged using the _ProducerMembrane wrapper. Non-streaming (pull) producers are supported by wrapping them with _PullToPush.

Method __init__ Undocumented
Method getHandle Return the OpenSSL.SSL.Connection object being used to encrypt and decrypt this connection.
Method makeConnection Connect this wrapper to the given transport and initialize the necessary OpenSSL.SSL.Connection with a memory BIO.
Method dataReceived Deliver any received bytes to the receive BIO and then read and deliver to the application any application-level data which becomes available as a result of this.
Method connectionLost Handle the possible repetition of calls to this method (due to either the underlying transport going away or due to an error at the TLS layer) and make sure the base implementation only gets invoked once.
Method loseConnection Send a TLS close alert and close the underlying connection.
Method abortConnection Tear down TLS state so that if the connection is aborted mid-handshake we don't deliver any further data from the application.
Method failVerification Abort the connection during connection setup, giving a reason that certificate verification failed.
Method write Process the given application bytes and send any resulting TLS traffic which arrives in the send BIO.
Method writeSequence Write a sequence of application bytes by joining them into one string and passing them to write.
Method getPeerCertificate Return an object with the peer's certificate info.
Method negotiatedProtocol
Method registerProducer Undocumented
Method unregisterProducer Undocumented
Instance Variable _tlsConnection The OpenSSL.SSL.Connection instance which is encrypted and decrypting this connection.
Instance Variable _lostTLSConnection A flag indicating whether connection loss has already been dealt with (True) or not (False). TLS disconnection is distinct from the underlying connection being lost.
Instance Variable _appSendBuffer application-level (cleartext) data that is waiting to be transferred to the TLS buffer, but can't be because the TLS connection is handshaking. (type: list of bytes)
Instance Variable _connectWrapped A flag indicating whether or not to call makeConnection on the wrapped protocol. This is for the reactor's twisted.internet.interfaces.ITLSTransport.startTLS implementation, since it has a protocol which it has already called makeConnection on, and which has no interest in a new transport. See #3821.
Instance Variable _handshakeDone A flag indicating whether or not the handshake is known to have completed successfully (True) or not (False). This is used to control error reporting behavior. If the handshake has not completed, the underlying OpenSSL.SSL.Error will be passed to the application's connectionLost method. If it has completed, any unexpected OpenSSL.SSL.Error will be turned into a ConnectionLost. This is weird; however, it is simply an attempt at a faithful re-implementation of the behavior provided by twisted.internet.ssl.
Instance Variable _reason If an unexpected OpenSSL.SSL.Error occurs which causes the connection to be lost, it is saved here. If appropriate, this may be used as the reason passed to the application protocol's connectionLost method.
Instance Variable _producer The current producer registered via registerProducer, or None if no producer has been registered or a previous one was unregistered.
Instance Variable _aborted abortConnection has been called. No further data will be received to the wrapped protocol's dataReceived. (type: bool)
Method _checkHandshakeStatus Ask OpenSSL to proceed with a handshake in progress.
Method _flushSendBIO Read any bytes out of the send BIO and write them to the underlying transport.
Method _flushReceiveBIO No summary
Method _shutdownTLS Initiate, or reply to, the shutdown handshake of the TLS layer.
Method _tlsShutdownFinished Called when TLS connection has gone away; tell underlying transport to disconnect.
Method _bufferedWrite Put the given octets into TLSMemoryBIOProtocol._appSendBuffer, and tell any listening producer that it should pause because we are now buffering.
Method _unbufferPendingWrites Un-buffer all waiting writes in TLSMemoryBIOProtocol._appSendBuffer.
Method _write Process the given application bytes and send any resulting TLS traffic which arrives in the send BIO.

Inherited from BaseProtocol (via ProtocolWrapper, Protocol):

Method connectionMade Called when a connection is made.

Inherited from BaseProtocol (via ProtocolWrapper, Protocol):

Method connectionMade Called when a connection is made.
_tlsConnection =
The OpenSSL.SSL.Connection instance which is encrypted and decrypting this connection.
_lostTLSConnection =
A flag indicating whether connection loss has already been dealt with (True) or not (False). TLS disconnection is distinct from the underlying connection being lost.
_appSendBuffer =
application-level (cleartext) data that is waiting to be transferred to the TLS buffer, but can't be because the TLS connection is handshaking. (type: list of bytes)
_connectWrapped =
A flag indicating whether or not to call makeConnection on the wrapped protocol. This is for the reactor's twisted.internet.interfaces.ITLSTransport.startTLS implementation, since it has a protocol which it has already called makeConnection on, and which has no interest in a new transport. See #3821.
_handshakeDone =
A flag indicating whether or not the handshake is known to have completed successfully (True) or not (False). This is used to control error reporting behavior. If the handshake has not completed, the underlying OpenSSL.SSL.Error will be passed to the application's connectionLost method. If it has completed, any unexpected OpenSSL.SSL.Error will be turned into a ConnectionLost. This is weird; however, it is simply an attempt at a faithful re-implementation of the behavior provided by twisted.internet.ssl.
_reason =
If an unexpected OpenSSL.SSL.Error occurs which causes the connection to be lost, it is saved here. If appropriate, this may be used as the reason passed to the application protocol's connectionLost method.
_producer =
The current producer registered via registerProducer, or None if no producer has been registered or a previous one was unregistered.
_aborted =
abortConnection has been called. No further data will be received to the wrapped protocol's dataReceived. (type: bool)
def __init__(self, factory, wrappedProtocol, _connectWrapped=True): (source)
overrides twisted.protocols.policies.ProtocolWrapper.__init__
Undocumented
def getHandle(self): (source)
from twisted.internet.interfaces.ISystemHandle

Return the OpenSSL.SSL.Connection object being used to encrypt and decrypt this connection.

This is done for the benefit of twisted.internet.ssl.Certificate's peerFromTransport and hostFromTransport methods only. A different system handle may be returned by future versions of this method.

def makeConnection(self, transport): (source)
from twisted.internet.interfaces.IProtocol
overrides twisted.protocols.policies.ProtocolWrapper.makeConnection

Connect this wrapper to the given transport and initialize the necessary OpenSSL.SSL.Connection with a memory BIO.

def _checkHandshakeStatus(self): (source)

Ask OpenSSL to proceed with a handshake in progress.

Initially, this just sends the ClientHello; after some bytes have been stuffed in to the Connection object by dataReceived, it will then respond to any Certificate or KeyExchange messages.

def _flushSendBIO(self): (source)

Read any bytes out of the send BIO and write them to the underlying transport.

def _flushReceiveBIO(self): (source)

Try to receive any application-level bytes which are now available because of a previous write into the receive BIO. This will take care of delivering any application-level bytes which are received to the protocol, as well as handling of the various exceptions which can come from trying to get such bytes.

def dataReceived(self, bytes): (source)
from twisted.internet.interfaces.IProtocol
overrides twisted.protocols.policies.ProtocolWrapper.dataReceived

Deliver any received bytes to the receive BIO and then read and deliver to the application any application-level data which becomes available as a result of this.

def _shutdownTLS(self): (source)

Initiate, or reply to, the shutdown handshake of the TLS layer.

def _tlsShutdownFinished(self, reason): (source)

Called when TLS connection has gone away; tell underlying transport to disconnect.

Parametersreasona Failure whose value is an Exception if we want to report that failure through to the wrapped protocol's connectionLost, or None if the reason that connectionLost should receive should be coming from the underlying transport. (type: Failure or None)
def connectionLost(self, reason): (source)
from twisted.internet.interfaces.IProtocol
overrides twisted.protocols.policies.ProtocolWrapper.connectionLost

Handle the possible repetition of calls to this method (due to either the underlying transport going away or due to an error at the TLS layer) and make sure the base implementation only gets invoked once.

def loseConnection(self): (source)
from twisted.internet.interfaces.ITransport
overrides twisted.protocols.policies.ProtocolWrapper.loseConnection

Send a TLS close alert and close the underlying connection.

def abortConnection(self): (source)
from twisted.internet.interfaces.ITCPTransport

Tear down TLS state so that if the connection is aborted mid-handshake we don't deliver any further data from the application.

def failVerification(self, reason): (source)

Abort the connection during connection setup, giving a reason that certificate verification failed.

ParametersreasonThe reason that the verification failed; reported to the application protocol's connectionLost method. (type: Failure)
def write(self, bytes): (source)
from twisted.internet.interfaces.ITransport
overrides twisted.protocols.policies.ProtocolWrapper.write

Process the given application bytes and send any resulting TLS traffic which arrives in the send BIO.

If loseConnection was called, subsequent calls to write will drop the bytes on the floor.

def _bufferedWrite(self, octets): (source)

Put the given octets into TLSMemoryBIOProtocol._appSendBuffer, and tell any listening producer that it should pause because we are now buffering.

def _unbufferPendingWrites(self): (source)

Un-buffer all waiting writes in TLSMemoryBIOProtocol._appSendBuffer.

def _write(self, bytes): (source)

Process the given application bytes and send any resulting TLS traffic which arrives in the send BIO.

This may be called by dataReceived with bytes that were buffered before loseConnection was called, which is why this function doesn't check for disconnection but accepts the bytes regardless.

def writeSequence(self, iovec): (source)
from twisted.internet.interfaces.ITransport
overrides twisted.protocols.policies.ProtocolWrapper.writeSequence

Write a sequence of application bytes by joining them into one string and passing them to write.

def getPeerCertificate(self): (source)
from twisted.internet.interfaces.ISSLTransport

Return an object with the peer's certificate info.

@property
def negotiatedProtocol(self): (source)
from twisted.internet.interfaces.INegotiated
See AlsoINegotiated.negotiatedProtocol
def registerProducer(self, producer, streaming): (source)
overrides twisted.protocols.policies.ProtocolWrapper.registerProducer
Undocumented
def unregisterProducer(self): (source)
overrides twisted.protocols.policies.ProtocolWrapper.unregisterProducer
Undocumented
API Documentation for Twisted, generated by pydoctor at 2017-06-11 10:59:01.