twisted.protocols.tls.TLSMemoryBIOProtocol

class documentation

class TLSMemoryBIOProtocol(ProtocolWrapper): (source)

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	`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	`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	`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	`failVerification`	Abort the connection during connection setup, giving a reason that certificate verification failed.
Method	`getHandle`	Return the `OpenSSL.SSL.Connection` object being used to encrypt and decrypt this connection.
Method	`getPeerCertificate`	Return an object with the peer's certificate info.
Method	`loseConnection`	Send a TLS close alert and close the underlying connection.
Method	`makeConnection`	Connect this wrapper to the given transport and initialize the necessary `OpenSSL.SSL.Connection` with a memory BIO.
Method	`registerProducer`	Undocumented
Method	`unregisterProducer`	Undocumented
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`.
Instance Variable	`connected`	Undocumented
Instance Variable	`disconnecting`	Undocumented
Property	`negotiatedProtocol`
Method	`_bufferedWrite`	Put the given octets into `TLSMemoryBIOProtocol._appSendBuffer`, and tell any listening producer that it should pause because we are now buffering.
Method	`_checkHandshakeStatus`	Ask OpenSSL to proceed with a handshake in progress.
Method	`_flushReceiveBIO`	No summary
Method	`_flushSendBIO`	Read any bytes out of the send BIO and write them to the underlying transport.
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	`_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.
Instance Variable	`_aborted`	`abortConnection` has been called. No further data will be received to the wrapped protocol's `dataReceived`.
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.
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	`_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	`_producer`	The current producer registered via `registerProducer`, or `None` if no producer has been registered or a previous one was unregistered.
Instance Variable	`_producerPaused`	Undocumented
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	`_tlsConnection`	The `OpenSSL.SSL.Connection` instance which is encrypted and decrypting this connection.

Inherited from ProtocolWrapper:

Method	`__getattr__`	Undocumented
Method	`getHost`	Undocumented
Method	`getPeer`	Undocumented
Method	`logPrefix`	Use a customized log prefix mentioning both the wrapped protocol and the current one.
Method	`stopConsuming`	Undocumented
Instance Variable	`factory`	The `WrappingFactory` which created this `ProtocolWrapper`.
Instance Variable	`wrappedProtocol`	An `IProtocol` provider to which `IProtocol` method calls onto this `ProtocolWrapper` will be proxied.

def __init__(self, factory, wrappedProtocol, _connectWrapped=True): (source)

overrides twisted.protocols.policies.ProtocolWrapper.__init__

Undocumented

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 connectionLost(self, reason): (source)

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 dataReceived(self, bytes): (source)

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 failVerification(self, reason): (source)

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

Parameters
reason:`Failure`	The reason that the verification failed; reported to the application protocol's `connectionLost` method.

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 getPeerCertificate(self): (source)

from twisted.internet.interfaces.ISSLTransport

Return an object with the peer's certificate info.

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 makeConnection(self, transport): (source)

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 registerProducer(self, producer, streaming): (source)

overrides twisted.protocols.policies.ProtocolWrapper.registerProducer

Undocumented

def unregisterProducer(self): (source)

overrides twisted.protocols.policies.ProtocolWrapper.unregisterProducer

Undocumented

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 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.

connected: bool = (source)

Undocumented

disconnecting: bool = (source)

overrides twisted.protocols.policies.ProtocolWrapper.disconnecting

Undocumented

@property
negotiatedProtocol = (source)

from twisted.internet.interfaces.INegotiated

See Also
`INegotiated.negotiatedProtocol`

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 _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 _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 _flushSendBIO(self): (source)

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

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.

Parameters
reason:`Failure` or `None`	a `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.

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.

_aborted: bool = (source)

abortConnection has been called. No further data will be received to the wrapped protocol's dataReceived.

_appSendBuffer: list of bytes = (source)

application-level (cleartext) data that is waiting to be transferred to the TLS buffer, but can't be because the TLS connection is handshaking.

_connectWrapped = (source)

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: bool = (source)

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.

_lostTLSConnection: bool = (source)

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.

_producer = (source)

The current producer registered via registerProducer, or None if no producer has been registered or a previous one was unregistered.

_producerPaused: bool = (source)

Undocumented

_reason = (source)

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.

_tlsConnection = (source)

The OpenSSL.SSL.Connection instance which is encrypted and decrypting this connection.