diff options
Diffstat (limited to 'src/lib/tlslite/integration/AsyncStateMachine.py')
| -rwxr-xr-x | src/lib/tlslite/integration/AsyncStateMachine.py | 235 |
1 files changed, 0 insertions, 235 deletions
diff --git a/src/lib/tlslite/integration/AsyncStateMachine.py b/src/lib/tlslite/integration/AsyncStateMachine.py deleted file mode 100755 index abed60432..000000000 --- a/src/lib/tlslite/integration/AsyncStateMachine.py +++ /dev/null @@ -1,235 +0,0 @@ -"""
-A state machine for using TLS Lite with asynchronous I/O.
-"""
-
-class AsyncStateMachine:
- """
- This is an abstract class that's used to integrate TLS Lite with
- asyncore and Twisted.
-
- This class signals wantsReadsEvent() and wantsWriteEvent(). When
- the underlying socket has become readable or writeable, the event
- should be passed to this class by calling inReadEvent() or
- inWriteEvent(). This class will then try to read or write through
- the socket, and will update its state appropriately.
-
- This class will forward higher-level events to its subclass. For
- example, when a complete TLS record has been received,
- outReadEvent() will be called with the decrypted data.
- """
-
- def __init__(self):
- self._clear()
-
- def _clear(self):
- #These store the various asynchronous operations (i.e.
- #generators). Only one of them, at most, is ever active at a
- #time.
- self.handshaker = None
- self.closer = None
- self.reader = None
- self.writer = None
-
- #This stores the result from the last call to the
- #currently active operation. If 0 it indicates that the
- #operation wants to read, if 1 it indicates that the
- #operation wants to write. If None, there is no active
- #operation.
- self.result = None
-
- def _checkAssert(self, maxActive=1):
- #This checks that only one operation, at most, is
- #active, and that self.result is set appropriately.
- activeOps = 0
- if self.handshaker:
- activeOps += 1
- if self.closer:
- activeOps += 1
- if self.reader:
- activeOps += 1
- if self.writer:
- activeOps += 1
-
- if self.result == None:
- if activeOps != 0:
- raise AssertionError()
- elif self.result in (0,1):
- if activeOps != 1:
- raise AssertionError()
- else:
- raise AssertionError()
- if activeOps > maxActive:
- raise AssertionError()
-
- def wantsReadEvent(self):
- """If the state machine wants to read.
-
- If an operation is active, this returns whether or not the
- operation wants to read from the socket. If an operation is
- not active, this returns None.
-
- @rtype: bool or None
- @return: If the state machine wants to read.
- """
- if self.result != None:
- return self.result == 0
- return None
-
- def wantsWriteEvent(self):
- """If the state machine wants to write.
-
- If an operation is active, this returns whether or not the
- operation wants to write to the socket. If an operation is
- not active, this returns None.
-
- @rtype: bool or None
- @return: If the state machine wants to write.
- """
- if self.result != None:
- return self.result == 1
- return None
-
- def outConnectEvent(self):
- """Called when a handshake operation completes.
-
- May be overridden in subclass.
- """
- pass
-
- def outCloseEvent(self):
- """Called when a close operation completes.
-
- May be overridden in subclass.
- """
- pass
-
- def outReadEvent(self, readBuffer):
- """Called when a read operation completes.
-
- May be overridden in subclass."""
- pass
-
- def outWriteEvent(self):
- """Called when a write operation completes.
-
- May be overridden in subclass."""
- pass
-
- def inReadEvent(self):
- """Tell the state machine it can read from the socket."""
- try:
- self._checkAssert()
- if self.handshaker:
- self._doHandshakeOp()
- elif self.closer:
- self._doCloseOp()
- elif self.reader:
- self._doReadOp()
- elif self.writer:
- self._doWriteOp()
- else:
- self.reader = self.tlsConnection.readAsync(16384)
- self._doReadOp()
- except:
- self._clear()
- raise
-
- def inWriteEvent(self):
- """Tell the state machine it can write to the socket."""
- try:
- self._checkAssert()
- if self.handshaker:
- self._doHandshakeOp()
- elif self.closer:
- self._doCloseOp()
- elif self.reader:
- self._doReadOp()
- elif self.writer:
- self._doWriteOp()
- else:
- self.outWriteEvent()
- except:
- self._clear()
- raise
-
- def _doHandshakeOp(self):
- try:
- self.result = self.handshaker.next()
- except StopIteration:
- self.handshaker = None
- self.result = None
- self.outConnectEvent()
-
- def _doCloseOp(self):
- try:
- self.result = self.closer.next()
- except StopIteration:
- self.closer = None
- self.result = None
- self.outCloseEvent()
-
- def _doReadOp(self):
- self.result = self.reader.next()
- if not self.result in (0,1):
- readBuffer = self.result
- self.reader = None
- self.result = None
- self.outReadEvent(readBuffer)
-
- def _doWriteOp(self):
- try:
- self.result = self.writer.next()
- except StopIteration:
- self.writer = None
- self.result = None
-
- def setHandshakeOp(self, handshaker):
- """Start a handshake operation.
-
- @type handshaker: generator
- @param handshaker: A generator created by using one of the
- asynchronous handshake functions (i.e. handshakeServerAsync, or
- handshakeClientxxx(..., async=True).
- """
- try:
- self._checkAssert(0)
- self.handshaker = handshaker
- self._doHandshakeOp()
- except:
- self._clear()
- raise
-
- def setServerHandshakeOp(self, **args):
- """Start a handshake operation.
-
- The arguments passed to this function will be forwarded to
- L{tlslite.TLSConnection.TLSConnection.handshakeServerAsync}.
- """
- handshaker = self.tlsConnection.handshakeServerAsync(**args)
- self.setHandshakeOp(handshaker)
-
- def setCloseOp(self):
- """Start a close operation.
- """
- try:
- self._checkAssert(0)
- self.closer = self.tlsConnection.closeAsync()
- self._doCloseOp()
- except:
- self._clear()
- raise
-
- def setWriteOp(self, writeBuffer):
- """Start a write operation.
-
- @type writeBuffer: str
- @param writeBuffer: The string to transmit.
- """
- try:
- self._checkAssert(0)
- self.writer = self.tlsConnection.writeAsync(writeBuffer)
- self._doWriteOp()
- except:
- self._clear()
- raise
-
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