# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.

"""
TCP support for IOCP reactor
"""

import socket, operator, errno, struct

from zope.interface import implements, classImplements

from twisted.internet import interfaces, error, address, main, defer
from twisted.internet.abstract import _LogOwner, isIPAddress, isIPv6Address
from twisted.internet.tcp import _SocketCloser, Connector as TCPConnector
from twisted.internet.tcp import _AbortingMixin, _BaseBaseClient, _BaseTCPClient
from twisted.python import log, failure, reflect, util

from twisted.internet.iocpreactor import iocpsupport as _iocp, abstract
from twisted.internet.iocpreactor.interfaces import IReadWriteHandle
from twisted.internet.iocpreactor.const import ERROR_IO_PENDING
from twisted.internet.iocpreactor.const import SO_UPDATE_CONNECT_CONTEXT
from twisted.internet.iocpreactor.const import SO_UPDATE_ACCEPT_CONTEXT
from twisted.internet.iocpreactor.const import ERROR_CONNECTION_REFUSED
from twisted.internet.iocpreactor.const import ERROR_NETWORK_UNREACHABLE

try:
from twisted.internet._newtls import startTLS as _startTLS
except ImportError:
_startTLS = None

# ConnectEx returns these. XXX: find out what it does for timeout
connectExErrors = {
ERROR_CONNECTION_REFUSED: errno.WSAECONNREFUSED,
ERROR_NETWORK_UNREACHABLE: errno.WSAENETUNREACH,
}

class Connection(abstract.FileHandle, _SocketCloser, _AbortingMixin):
"""
@ivar TLS: C{False} to indicate the connection is in normal TCP mode,
C{True} to indicate that TLS has been started and that operations must
be routed through the L{TLSMemoryBIOProtocol} instance.
"""
implements(IReadWriteHandle, interfaces.ITCPTransport,
interfaces.ISystemHandle)

TLS = False


def __init__(self, sock, proto, reactor=None):
abstract.FileHandle.__init__(self, reactor)
self.socket = sock
self.getFileHandle = sock.fileno
self.protocol = proto


def getHandle(self):
return self.socket


def dataReceived(self, rbuffer):
# XXX: some day, we'll have protocols that can handle raw buffers
self.protocol.dataReceived(str(rbuffer))


def readFromHandle(self, bufflist, evt):
return _iocp.recv(self.getFileHandle(), bufflist, evt)


def writeToHandle(self, buff, evt):
"""
Send C{buff} to current file handle using C{_iocp.send}. The buffer
sent is limited to a size of C{self.SEND_LIMIT}.
"""
return _iocp.send(self.getFileHandle(),
buffer(buff, 0, self.SEND_LIMIT), evt)


def _closeWriteConnection(self):
try:
getattr(self.socket, self._socketShutdownMethod)(1)
except socket.error:
pass
p = interfaces.IHalfCloseableProtocol(self.protocol, None)
if p:
try:
p.writeConnectionLost()
except:
f = failure.Failure()
log.err()
self.connectionLost(f)


def readConnectionLost(self, reason):
p = interfaces.IHalfCloseableProtocol(self.protocol, None)
if p:
try:
p.readConnectionLost()
except:
log.err()
self.connectionLost(failure.Failure())
else:
self.connectionLost(reason)


def connectionLost(self, reason):
if self.disconnected:
return
abstract.FileHandle.connectionLost(self, reason)
isClean = (reason is None or
not reason.check(error.ConnectionAborted))
self._closeSocket(isClean)
protocol = self.protocol
del self.protocol
del self.socket
del self.getFileHandle
protocol.connectionLost(reason)


def logPrefix(self):
"""
Return the prefix to log with when I own the logging thread.
"""
return self.logstr


def getTcpNoDelay(self):
return operator.truth(self.socket.getsockopt(socket.IPPROTO_TCP,
socket.TCP_NODELAY))


def setTcpNoDelay(self, enabled):
self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, enabled)


def getTcpKeepAlive(self):
return operator.truth(self.socket.getsockopt(socket.SOL_SOCKET,
socket.SO_KEEPALIVE))


def setTcpKeepAlive(self, enabled):
self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, enabled)


if _startTLS is not None:
def startTLS(self, contextFactory, normal=True):
"""
@see: L{ITLSTransport.startTLS}
"""
_startTLS(self, contextFactory, normal, abstract.FileHandle)


def write(self, data):
"""
Write some data, either directly to the underlying handle or, if TLS
has been started, to the L{TLSMemoryBIOProtocol} for it to encrypt and
send.

@see: L{ITCPTransport.write}
"""
if self.disconnected:
return
if self.TLS:
self.protocol.write(data)
else:
abstract.FileHandle.write(self, data)


def writeSequence(self, iovec):
"""
Write some data, either directly to the underlying handle or, if TLS
has been started, to the L{TLSMemoryBIOProtocol} for it to encrypt and
send.

@see: L{ITCPTransport.writeSequence}
"""
if self.disconnected:
return
if self.TLS:
self.protocol.writeSequence(iovec)
else:
abstract.FileHandle.writeSequence(self, iovec)


def loseConnection(self, reason=None):
"""
Close the underlying handle or, if TLS has been started, first shut it
down.

@see: L{ITCPTransport.loseConnection}
"""
if self.TLS:
if self.connected and not self.disconnecting:
self.protocol.loseConnection()
else:
abstract.FileHandle.loseConnection(self, reason)


def registerProducer(self, producer, streaming):
"""
Register a producer.

If TLS is enabled, the TLS connection handles this.
"""
if self.TLS:
# Registering a producer before we're connected shouldn't be a
# problem. If we end up with a write(), that's already handled in
# the write() code above, and there are no other potential
# side-effects.
self.protocol.registerProducer(producer, streaming)
else:
abstract.FileHandle.registerProducer(self, producer, streaming)


def unregisterProducer(self):
"""
Unregister a producer.

If TLS is enabled, the TLS connection handles this.
"""
if self.TLS:
self.protocol.unregisterProducer()
else:
abstract.FileHandle.unregisterProducer(self)

if _startTLS is not None:
classImplements(Connection, interfaces.ITLSTransport)



class Client(_BaseBaseClient, _BaseTCPClient, Connection):
"""
@ivar _tlsClientDefault: Always C{True}, indicating that this is a client
connection, and by default when TLS is negotiated this class will act as
a TLS client.
"""
addressFamily = socket.AF_INET
socketType = socket.SOCK_STREAM

_tlsClientDefault = True
_commonConnection = Connection

def __init__(self, host, port, bindAddress, connector, reactor):
# ConnectEx documentation says socket _has_ to be bound
if bindAddress is None:
bindAddress = ('', 0)
self.reactor = reactor # createInternetSocket needs this
_BaseTCPClient.__init__(self, host, port, bindAddress, connector,
reactor)


def createInternetSocket(self):
"""
Create a socket registered with the IOCP reactor.

@see: L{_BaseTCPClient}
"""
return self.reactor.createSocket(self.addressFamily, self.socketType)


def _collectSocketDetails(self):
"""
Clean up potentially circular references to the socket and to its
C{getFileHandle} method.

@see: L{_BaseBaseClient}
"""
del self.socket, self.getFileHandle


def _stopReadingAndWriting(self):
"""
Remove the active handle from the reactor.

@see: L{_BaseBaseClient}
"""
self.reactor.removeActiveHandle(self)


def cbConnect(self, rc, bytes, evt):
if rc:
rc = connectExErrors.get(rc, rc)
self.failIfNotConnected(error.getConnectError((rc,
errno.errorcode.get(rc, 'Unknown error'))))
else:
self.socket.setsockopt(
socket.SOL_SOCKET, SO_UPDATE_CONNECT_CONTEXT,
struct.pack('P', self.socket.fileno()))
self.protocol = self.connector.buildProtocol(self.getPeer())
self.connected = True
logPrefix = self._getLogPrefix(self.protocol)
self.logstr = logPrefix + ",client"
self.protocol.makeConnection(self)
self.startReading()


def doConnect(self):
if not hasattr(self, "connector"):
# this happens if we connector.stopConnecting in
# factory.startedConnecting
return
assert _iocp.have_connectex
self.reactor.addActiveHandle(self)
evt = _iocp.Event(self.cbConnect, self)

rc = _iocp.connect(self.socket.fileno(), self.realAddress, evt)
if rc and rc != ERROR_IO_PENDING:
self.cbConnect(rc, 0, evt)



class Server(Connection):
"""
Serverside socket-stream connection class.

I am a serverside network connection transport; a socket which came from an
accept() on a server.

@ivar _tlsClientDefault: Always C{False}, indicating that this is a server
connection, and by default when TLS is negotiated this class will act as
a TLS server.
"""

_tlsClientDefault = False


def __init__(self, sock, protocol, clientAddr, serverAddr, sessionno, reactor):
"""
Server(sock, protocol, client, server, sessionno)

Initialize me with a socket, a protocol, a descriptor for my peer (a
tuple of host, port describing the other end of the connection), an
instance of Port, and a session number.
"""
Connection.__init__(self, sock, protocol, reactor)
self.serverAddr = serverAddr
self.clientAddr = clientAddr
self.sessionno = sessionno
logPrefix = self._getLogPrefix(self.protocol)
self.logstr = "%s,%s,%s" % (logPrefix, sessionno, self.clientAddr.host)
self.repstr = "<%s #%s on %s>" % (self.protocol.__class__.__name__,
self.sessionno, self.serverAddr.port)
self.connected = True
self.startReading()


def __repr__(self):
"""
A string representation of this connection.
"""
return self.repstr


def getHost(self):
"""
Returns an IPv4Address.

This indicates the server's address.
"""
return self.serverAddr


def getPeer(self):
"""
Returns an IPv4Address.

This indicates the client's address.
"""
return self.clientAddr



class Connector(TCPConnector):
def _makeTransport(self):
return Client(self.host, self.port, self.bindAddress, self,
self.reactor)



class Port(_SocketCloser, _LogOwner):
implements(interfaces.IListeningPort)

connected = False
disconnected = False
disconnecting = False
addressFamily = socket.AF_INET
socketType = socket.SOCK_STREAM
_addressType = address.IPv4Address
sessionno = 0

# Actual port number being listened on, only set to a non-None
# value when we are actually listening.
_realPortNumber = None

# A string describing the connections which will be created by this port.
# Normally this is C{"TCP"}, since this is a TCP port, but when the TLS
# implementation re-uses this class it overrides the value with C{"TLS"}.
# Only used for logging.
_type = 'TCP'

def __init__(self, port, factory, backlog=50, interface='', reactor=None):
self.port = port
self.factory = factory
self.backlog = backlog
self.interface = interface
self.reactor = reactor
if isIPv6Address(interface):
self.addressFamily = socket.AF_INET6
self._addressType = address.IPv6Address


def __repr__(self):
if self._realPortNumber is not None:
return "<%s of %s on %s>" % (self.__class__,
self.factory.__class__,
self._realPortNumber)
else:
return "<%s of %s (not listening)>" % (self.__class__,
self.factory.__class__)


def startListening(self):
try:
skt = self.reactor.createSocket(self.addressFamily,
self.socketType)
# TODO: resolve self.interface if necessary
if self.addressFamily == socket.AF_INET6:
addr = socket.getaddrinfo(self.interface, self.port)[0][4]
else:
addr = (self.interface, self.port)
skt.bind(addr)
except socket.error, le:
raise error.CannotListenError, (self.interface, self.port, le)

self.addrLen = _iocp.maxAddrLen(skt.fileno())

# Make sure that if we listened on port 0, we update that to
# reflect what the OS actually assigned us.
self._realPortNumber = skt.getsockname()[1]

log.msg("%s starting on %s" % (self._getLogPrefix(self.factory),
self._realPortNumber))

self.factory.doStart()
skt.listen(self.backlog)
self.connected = True
self.disconnected = False
self.reactor.addActiveHandle(self)
self.socket = skt
self.getFileHandle = self.socket.fileno
self.doAccept()


def loseConnection(self, connDone=failure.Failure(main.CONNECTION_DONE)):
"""
Stop accepting connections on this port.

This will shut down my socket and call self.connectionLost().
It returns a deferred which will fire successfully when the
port is actually closed.
"""
self.disconnecting = True
if self.connected:
self.deferred = defer.Deferred()
self.reactor.callLater(0, self.connectionLost, connDone)
return self.deferred

stopListening = loseConnection


def _logConnectionLostMsg(self):
"""
Log message for closing port
"""
log.msg('(%s Port %s Closed)' % (self._type, self._realPortNumber))


def connectionLost(self, reason):
"""
Cleans up the socket.
"""
self._logConnectionLostMsg()
self._realPortNumber = None
d = None
if hasattr(self, "deferred"):
d = self.deferred
del self.deferred

self.disconnected = True
self.reactor.removeActiveHandle(self)
self.connected = False
self._closeSocket(True)
del self.socket
del self.getFileHandle

try:
self.factory.doStop()
except:
self.disconnecting = False
if d is not None:
d.errback(failure.Failure())
else:
raise
else:
self.disconnecting = False
if d is not None:
d.callback(None)


def logPrefix(self):
"""
Returns the name of my class, to prefix log entries with.
"""
return reflect.qual(self.factory.__class__)


def getHost(self):
"""
Returns an IPv4Address.

This indicates the server's address.
"""
host, port = self.socket.getsockname()[:2]
return self._addressType('TCP', host, port)


def cbAccept(self, rc, bytes, evt):
self.handleAccept(rc, evt)
if not (self.disconnecting or self.disconnected):
self.doAccept()


def handleAccept(self, rc, evt):
if self.disconnecting or self.disconnected:
return False

# possible errors:
# (WSAEMFILE, WSAENOBUFS, WSAENFILE, WSAENOMEM, WSAECONNABORTED)
if rc:
log.msg("Could not accept new connection -- %s (%s)" %
(errno.errorcode.get(rc, 'unknown error'), rc))
return False
else:
evt.newskt.setsockopt(
socket.SOL_SOCKET, SO_UPDATE_ACCEPT_CONTEXT,
struct.pack('P', self.socket.fileno()))
family, lAddr, rAddr = _iocp.get_accept_addrs(evt.newskt.fileno(),
evt.buff)
assert family == self.addressFamily

protocol = self.factory.buildProtocol(
self._addressType('TCP', rAddr[0], rAddr[1]))
if protocol is None:
evt.newskt.close()
else:
s = self.sessionno
self.sessionno = s+1
transport = Server(evt.newskt, protocol,
self._addressType('TCP', rAddr[0], rAddr[1]),
self._addressType('TCP', lAddr[0], lAddr[1]),
s, self.reactor)
protocol.makeConnection(transport)
return True


def doAccept(self):
evt = _iocp.Event(self.cbAccept, self)

# see AcceptEx documentation
evt.buff = buff = _iocp.AllocateReadBuffer(2 * (self.addrLen + 16))

evt.newskt = newskt = self.reactor.createSocket(self.addressFamily,
self.socketType)
rc = _iocp.accept(self.socket.fileno(), newskt.fileno(), buff, evt)

if rc and rc != ERROR_IO_PENDING:
self.handleAccept(rc, evt)