def tcphandler(self, sock, addr, maxsize=16386, timeout=60):
'''Handle an established TCP connection, and close it if no activity for timeout.'''
remotes = []
try:
buffer = '' # buffer of data
while True:
try: data = yield multitask.recv(sock, maxsize, timeout=timeout)
except multitask.Timeout: break # no activity for the timeout
if not data: continue
buffer = buffer + data
if len(buffer) < 2: continue # wait for length atleast
size = struct.unpack('!H', buffer[:2])
if size>maxsize: buffer=''; print 'Network.tcphandler() something wrong, ignoring'; continue # TODO: something wrong happened, the protocol went out of sync?
if len(buffer)<(2+size): continue # we need more data.
data, buffer = buffer[2:2+size], buffer[2+size:]
msg, remote = self.parse(data, addr, sock.type)
if not msg: continue # TODO: handle non-p2p message
if _debug: print self.name, 'tcp-received %s=>%s: %r'%(remote.hostport, self.nodetcp.hostport, msg)
if remote not in self.tcpc:
self.tcpc[remote] = sock # update the table, indicating we have a connection to this node.
remotes.append(remote) # store the remote node so that we can clear tcpc on exit
if 'ack' in msg: del msg['ack'] # just remove the ack attribute. No need to ack on tcp.
msg['remote'] = remote # put remote as an attribute in msg before putting on queue.
yield self.put(msg) # put the parsed msg so that other interested party may get it.
finally:
toremove = map(lambda y: y[0], filter(lambda x: x[1] == sock, self.tcpc.items()))
for node in toremove: del self.tcpc[node]
def _tcpreceiver(self, stack, sock, remote, maxsize=16386): # handle the messages on the given TCP connection.
self.conn[remote] = sock
pending = ''
while True:
data = yield multitask.recv(sock, maxsize)
logger.debug('%r=>%r on type=%r\n%s', remote, sock.getsockname(), stack.transport.type, data)
if data:
pending += data
while True:
msg = pending
index1, index2 = msg.find('\n\n'), msg.find('\n\r\n')
if index2 > 0 and index1 > 0:
if index1 < index2:
index = index1 + 2
else:
index = index2 + 3
elif index1 > 0:
index = index1 + 2
elif index2 > 0:
index = index2 + 3
else:
logger.debug('no CRLF found'); break # no header part yet
match = re.search(r'content-length\s*:\s*(\d+)\r?\n', msg.lower())
if not match: logger.debug('no content-length found'); break # no content length yet
length = int(match.group(1))
if len(msg) < index+length: logger.debug('has more content %d < %d (%d+%d)', len(msg), index+length, index, length); break # pending further content.
total, pending = msg[:index+length], msg[index+length:]
try: stack.received(total, remote)
except: logger.exception('receiving')
else: # socket closed
break
try: del self.conn[remote]
except: pass
def tcpreceiver(sock, remote): # handle a new incoming TCP connection
while True:
data = (yield multitask.recv(sock, maxsize))
if not data:
break # socket closed
type, length, magic = struct.unpack("!HHL", data[:8])
valid = (type & 0xC000 == 0) and magic == Message.MAGIC and length <= (maxsize - 8) # valid
if valid:
yield datahandler(sock, data, remote)
if _debug:
print "tcpreceiver() finished data handler"
else:
handler(sock, data, remote)
def tcpreceiver(sock, remote): # handle a new incoming TCP connection
while True:
data = (yield multitask.recv(sock, maxsize))
if not data: break # socket closed
type, length, magic = struct.unpack('!HHL', data[:8])
valid = (type & 0xC000
== 0) and magic == Message.MAGIC and length <= (
maxsize - 8) # valid
if valid:
yield datahandler(sock, data, remote)
if _debug: print 'tcpreceiver() finished data handler'
else:
handler(sock, data, remote)
def tcphandler(self, sock, addr, maxsize=16386, timeout=60):
'''Handle an established TCP connection, and close it if no activity for timeout.'''
remotes = []
try:
buffer = '' # buffer of data
while True:
try:
data = yield multitask.recv(sock, maxsize, timeout=timeout)
except multitask.Timeout:
break # no activity for the timeout
if not data: continue
buffer = buffer + data
if len(buffer) < 2: continue # wait for length atleast
size = struct.unpack('!H', buffer[:2])
if size > maxsize:
buffer = ''
print 'Network.tcphandler() something wrong, ignoring'
continue # TODO: something wrong happened, the protocol went out of sync?
if len(buffer) < (2 + size): continue # we need more data.
data, buffer = buffer[2:2 + size], buffer[2 + size:]
msg, remote = self.parse(data, addr, sock.type)
if not msg: continue # TODO: handle non-p2p message
if _debug:
print self.name, 'tcp-received %s=>%s: %r' % (
remote.hostport, self.nodetcp.hostport, msg)
if remote not in self.tcpc:
self.tcpc[
remote] = sock # update the table, indicating we have a connection to this node.
remotes.append(
remote
) # store the remote node so that we can clear tcpc on exit
if 'ack' in msg:
del msg[
'ack'] # just remove the ack attribute. No need to ack on tcp.
msg['remote'] = remote # put remote as an attribute in msg before putting on queue.
yield self.put(
msg
) # put the parsed msg so that other interested party may get it.
finally:
toremove = map(lambda y: y[0],
filter(lambda x: x[1] == sock, self.tcpc.items()))
for node in toremove:
del self.tcpc[node]
def request(sock, server=None, **kwargs):
"""Send a STUN client request with retransmissions and return the response.
This is a generator function, and can be called as
response, external = yield request(sock, ('stun.iptel.org', 3478))
It raises ValueError in case of failure and multitask.Timeout in case of timeout
or failure to connect TCP or invalid response received. For TCP, the sock remains
connected after successful return or exception from this function.
Arguments are as follows:
sock: the socket to use for sending request and receiving response.
server: optional server (ip, port), defaults to defaultServers[0]. For TCP if sock
is already connected, then server argument is ignored.
method: optional STUN method, defaults to Message.BINDING.
tid: optional transaction id, by default generates a new.
attrs: optional attributes, by default empty list [].
rto: optional RTO, defaults to 0.1 for UDP and 9.3 for TCP.
retry: optional retry count, defaults to 7 for UDP and 1 for TCP.
maxsize: optional maximum packet size, defaults to 1500.
handler: optional handler function, that receives any message that was received
but not handled by the request method.
The handler argument allows demultiplexing other types of received messages on the
same socket. Note that raising an exception is not good, because we still want to
wait for response instead of exiting. The handler is invoked as
handler(sock, remote, data) where data is raw data string and remote is usually
server (ip, port). If no handler is specified, then invalid data raises a ValueError.
"""
server = server or defaultServers[0] # use first server if missing
handler = kwargs.get("handler", None)
maxsize = kwargs.get("maxsize", 1500)
m = Message()
m.method = kwargs.get("method", Message.BINDING)
m.type = Message.REQUEST
m.tid = kwargs.get("tid", urandom(12))
m.attrs = kwargs.get("attrs", [])
mstr = str(m) # formatted message bytes to send
if len(mstr) >= maxsize:
raise ValueError, "Cannot send packet of length>%d" % (maxsize)
if sock.type == socket.SOCK_STREAM:
remote = None
try:
remote = sock.getpeername()
except:
pass
if not remote:
try:
sock.connect(server)
remote = server # connect if not already connected.
except:
raise multitask.Timeout() # can't connect, then raise a timeout error.
tcp, rto, retry = True, kwargs.get("rto", 9.3), kwargs.get("retry", 1)
else:
tcp, rto, retry = False, kwargs.get("rto", 0.100), kwargs.get("retry", 7)
while retry > 0:
retry = retry - 1
if _debug:
print "sending STUN request method=%d, len=%d, remaining-retry=%d" % (m.method, len(mstr), retry)
if tcp:
yield multitask.send(sock, mstr) # send the request
else:
yield multitask.sendto(sock, mstr, server)
try:
if tcp: # receiving a TCP packet is complicated. remote is already set
data = (yield multitask.recv(sock, maxsize, timeout=rto))
if not data:
break
if _debug:
print "request() received data"
type, length, magic = struct.unpack("!HHL", data[:8])
if type & 0xC000 != 0 or magic != Message.MAGIC:
raise ValueError, "invalid STUN response from server type=0x%x, magic=0x%x" % (type, magic)
if length > (maxsize - 8):
raise ValueError, "very large response length[%d]>%d" % (length + 8, maxsize)
else: # receive a UDP datagram
data, remote = (yield multitask.recvfrom(sock, maxsize, timeout=rto))
if data:
try:
response = Message(data) # parse the message if any
if _debug:
print "received STUN message method=%d, type=%d" % (response.method, response.type)
except:
if _debug:
print "received invalid STUN message len=%d" % (len(response))
if handler:
handler(sock, remote, data) # allow app to demultiplex
continue # retry next
else:
raise ValueError, "Invalid response from server"
if response.tid != m.tid:
if _debug:
print "The tid does not match. ignoring"
if handler:
handler(sock, remote, data)
continue # probably a old response, don't raise exception.
external = None
for attr in response.attrs:
if not attr.optional and attr.type not in Attribute.knownTypes:
raise ValueError, "Attribute 0x%04x not understood in response" % attr.type
if response.type == Message.RESPONSE: # success response
for attr in response.attrs:
if m.method == Message.BINDING:
if attr.type == Attribute.XOR_MAPPED_ADDRESS:
external = attr.xorAddress # (family, ip, port)
elif attr.type == Attribute.MAPPED_ADDRESS: # for backward compatibility with RFC 3489
external = attr.address
elif response.type == Message.ERROR: # error response
error = None
for attr in response.attrs:
if attrs.type == Attribute.ERROR_CODE:
error = attrs.error # (code, reason)
break
raise ValueError, "Request failed with error %r" % error
if external:
external = external[1:] # ignore the address family
raise StopIteration(response, external) # result to the caller
# TODO: else do we continue or raise an error?
except multitask.Timeout:
rto = rto * 2 # double the rto
except StopIteration:
if _debug:
print "request() returning external=" + str(external)
raise
except: # any other exception, fall back to Timeout exception
if _debug:
print "Some ValueError exception", sys.exc_info()
break
raise multitask.Timeout # no response after all retransmissions
def request(sock, server=None, **kwargs):
'''Send a STUN client request with retransmissions and return the response.
This is a generator function, and can be called as
response, external = yield request(sock, ('stun.iptel.org', 3478))
It raises ValueError in case of failure and multitask.Timeout in case of timeout
or failure to connect TCP or invalid response received. For TCP, the sock remains
connected after successful return or exception from this function.
Arguments are as follows:
sock: the socket to use for sending request and receiving response.
server: optional server (ip, port), defaults to defaultServers[0]. For TCP if sock
is already connected, then server argument is ignored.
method: optional STUN method, defaults to Message.BINDING.
tid: optional transaction id, by default generates a new.
attrs: optional attributes, by default empty list [].
rto: optional RTO, defaults to 0.1 for UDP and 9.3 for TCP.
retry: optional retry count, defaults to 7 for UDP and 1 for TCP.
maxsize: optional maximum packet size, defaults to 1500.
handler: optional handler function, that receives any message that was received
but not handled by the request method.
The handler argument allows demultiplexing other types of received messages on the
same socket. Note that raising an exception is not good, because we still want to
wait for response instead of exiting. The handler is invoked as
handler(sock, remote, data) where data is raw data string and remote is usually
server (ip, port). If no handler is specified, then invalid data raises a ValueError.
'''
server = server or defaultServers[0] # use first server if missing
handler = kwargs.get('handler', None)
maxsize = kwargs.get('maxsize', 1500)
m = Message()
m.method = kwargs.get('method', Message.BINDING)
m.type = Message.REQUEST
m.tid = kwargs.get('tid', urandom(12))
m.attrs = kwargs.get('attrs', [])
mstr = str(m) # formatted message bytes to send
if len(mstr) >= maxsize:
raise ValueError, 'Cannot send packet of length>%d' % (maxsize)
if sock.type == socket.SOCK_STREAM:
remote = None
try:
remote = sock.getpeername()
except:
pass
if not remote:
try:
sock.connect(server)
remote = server # connect if not already connected.
except:
raise multitask.Timeout(
) # can't connect, then raise a timeout error.
tcp, rto, retry = True, kwargs.get('rto', 9.3), kwargs.get('retry', 1)
else:
tcp, rto, retry = False, kwargs.get('rto',
0.100), kwargs.get('retry', 7)
while retry > 0:
retry = retry - 1
if _debug:
print 'sending STUN request method=%d, len=%d, remaining-retry=%d' % (
m.method, len(mstr), retry)
if tcp:
yield multitask.send(sock, mstr) # send the request
else:
yield multitask.sendto(sock, mstr, server)
try:
if tcp: # receiving a TCP packet is complicated. remote is already set
data = (yield multitask.recv(sock, maxsize, timeout=rto))
if not data: break
if _debug: print 'request() received data'
type, length, magic = struct.unpack('!HHL', data[:8])
if type & 0xC000 != 0 or magic != Message.MAGIC:
raise ValueError, 'invalid STUN response from server type=0x%x, magic=0x%x' % (
type, magic)
if length > (maxsize - 8):
raise ValueError, 'very large response length[%d]>%d' % (
length + 8, maxsize)
else: # receive a UDP datagram
data, remote = (yield multitask.recvfrom(sock,
maxsize,
timeout=rto))
if data:
try:
response = Message(data) # parse the message if any
if _debug:
print 'received STUN message method=%d, type=%d' % (
response.method, response.type)
except:
if _debug:
print 'received invalid STUN message len=%d' % (
len(response))
if handler:
handler(sock, remote, data) # allow app to demultiplex
continue # retry next
else:
raise ValueError, 'Invalid response from server'
if response.tid != m.tid:
if _debug: print 'The tid does not match. ignoring'
if handler: handler(sock, remote, data)
continue # probably a old response, don't raise exception.
external = None
for attr in response.attrs:
if not attr.optional and attr.type not in Attribute.knownTypes:
raise ValueError, 'Attribute 0x%04x not understood in response' % attr.type
if response.type == Message.RESPONSE: # success response
for attr in response.attrs:
if m.method == Message.BINDING:
if attr.type == Attribute.XOR_MAPPED_ADDRESS:
external = attr.xorAddress # (family, ip, port)
elif attr.type == Attribute.MAPPED_ADDRESS: # for backward compatibility with RFC 3489
external = attr.address
elif response.type == Message.ERROR: # error response
error = None
for attr in response.attrs:
if attrs.type == Attribute.ERROR_CODE:
error = attrs.error # (code, reason)
break
raise ValueError, 'Request failed with error %r' % error
if external:
external = external[1:] # ignore the address family
raise StopIteration(response,
external) # result to the caller
# TODO: else do we continue or raise an error?
except multitask.Timeout:
rto = rto * 2 # double the rto
except StopIteration:
if _debug: print 'request() returning external=' + str(external)
raise
except: # any other exception, fall back to Timeout exception
if _debug: print 'Some ValueError exception', sys.exc_info()
break
raise multitask.Timeout # no response after all retransmissions
def _wsreceiver(self, stack, sock, remote, maxsize=16386): # handle the messages on the given TCP connection.
handshake = False
pending = ''
while True:
data = yield multitask.recv(sock, maxsize)
logger.debug('%r=>%r on type=%r length %d', sock.getpeername(), sock.getsockname(), stack.transport.type, len(data))
if data:
pending += data
if not handshake:
# do handshake first
logger.debug('handshake\n%s', data)
if pending.startswith('<policy-file-request/>'):
logger.debug('received policy-file-request, responding for port %r'%(stack.transport.port,))
sock.sendall('''<!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy><allow-access-from domain="*" to-ports="%d"/></cross-domain-policy>'''%(stack.transport.port,))
sock.close()
break
else:
msg = pending
index1, index2 = msg.find('\n\n'), msg.find('\n\r\n')
if index2 > 0 and index1 > 0:
if index1 < index2:
index = index1 + 2
else:
index = index2 + 3
elif index1 > 0:
index = index1 + 2
elif index2 > 0:
index = index2 + 3
else:
logger.debug('no CRLF found'); break # no header part yet, wait for more
match = re.search(r'content-length\s*:\s*(\d+)\r?\n', msg[:index].lower())
length = int(match.group(1)) if match else 0
if len(msg) < index+length: logger.debug('has more content %d < %d (%d+%d)', len(msg), index+length, index, length); break # pending further content.
total, pending = pending[:index+length], pending[index+length:]
try:
lines = total.split('\n')
headers = dict([(h.strip().lower(), value.strip()) for h,sep,value in [line.strip().partition(':') for line in lines[1:] if line.strip()]])
method, path, protocol = lines[0].split(' ')
headers.update(method=method, path=path, protocol=protocol)
if method != 'GET' or headers.get('upgrade', '').lower() != 'websocket' or headers.get('connection', '') != 'Upgrade' or headers.get('sec-websocket-protocol', '').lower() != 'sip':
raise ValueError, 'Invalid WS request with invalid method, upgrade, connection or protocol'
if int(headers.get('sec-websocket-version', '0')) < 13: # version is too old
raise ValueError, 'Old or missing websocket version. Must be >= 13'
stack.websocket = headers # store the handshake parameters
key = headers.get('sec-websocket-key','')
# key = 'dGhlIHNhbXBsZSBub25jZQ==' # used for testing, generates accept = s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
accept = base64.b64encode(hashlib.sha1(key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11").digest())
response = '\r\n'.join([
'HTTP/1.1 101 Switching Protocols', 'Upgrade: websocket', 'Connection: Upgrade',
'Sec-WebSocket-Accept: %s'%(accept,), 'Sec-WebSocket-Protocol: sip']) + '\r\n\r\n'
logger.debug('%r=>%r\n%s', sock.getsockname(), sock.getpeername(), response)
sock.sendall(response)
handshake = True
self.conn[remote] = sock
except:
logger.exception('parsing websocket request')
sock.close()
break
else:
# process request
while pending:
m = pending
opcode, length = ord(m[0]) & 0x0f, ord(m[1]) & 0x7f
if opcode != 0x01:
logger.warning('only text opcode is supported')
if length == 126:
length = struct.unpack('>H', m[2:4])[0]
masks = m[4:8]
offset = 8
elif length == 127:
lengths = struct.unpack('>II', m[2:10])
length = lengths[0] * 2**32 + lengths[1]
masks = m[10:14]
offset = 14
else:
masks = m[2:6]
offset = 6
logger.debug('offset=%r length=%r', offset, length)
if len(m) < offset + length:
logger.debug('incomplete message')
break
decoded, encoded, pending = [], m[offset:offset+length], m[offset+length:]
for i, ch in enumerate(encoded):
decoded.append(chr(ord(ch) ^ ord(masks[i % 4])))
decoded = ''.join(decoded)
logger.debug('websocket received\n%s', decoded)
try: stack.received(decoded, remote)
except: logger.exception('receiving')
else: # socket closed
break
try: del self.conn[remote]
except: pass
