better ssdp datagram parsing

txupnp/gateway.py

@@ -1,4 +1,4 @@
-import binascii
+import json
 import logging
 from twisted.internet import defer
 import treq
@@ -19,6 +19,15 @@ class Service(object):
         self.subscribe_path = eventSubURL
         self.scpd_path = SCPDURL
 
+    def get_info(self):
+        return {
+            "service_type": self.service_type,
+            "service_id": self.service_id,
+            "control_path": self.control_path,
+            "subscribe_path": self.subscribe_path,
+            "scpd_path": self.scpd_path
+        }
+
 
 class Device(object):
     def __init__(self, _root_device, deviceType=None, friendlyName=None, manufacturer=None, manufacturerURL=None,
@@ -45,6 +54,17 @@ class Device(object):
         devices = [Device(self._root_device, **deviceList[k]) for k in deviceList]
         self._root_device.devices.extend(devices)
 
+    def get_info(self):
+        return {
+            'device_type': self.device_type,
+            'friendly_name': self.friendly_name,
+            'manufacturers': self.manufacturer,
+            'model_name': self.model_name,
+            'model_number': self.model_number,
+            'serial_number': self.serial_number,
+            'udn': self.udn
+        }
+
 
 class RootDevice(object):
     def __init__(self, xml_string):
@@ -61,7 +81,7 @@ class RootDevice(object):
         if root:
             root_device = Device(self, **(root["device"]))
             self.devices.append(root_device)
-            log.info("finished setting up root device. %i devices and %i services", len(self.devices), len(self.services))
+            log.info("finished setting up root gateway. %i devices and %i services", len(self.devices), len(self.services))
 
 
 class Gateway(object):
@@ -77,14 +97,41 @@ class Gateway(object):
         self.port = int(BASE_PORT_REGEX.findall(self.location)[0])
         self._device = None
 
+    def debug_device(self):
+        def default_byte(x):
+            if isinstance(x, bytes):
+                return x.decode()
+            return x
+
+        devices = []
+        for device in self._device.devices:
+            info = device.get_info()
+            devices.append(info)
+        services = []
+        for service in self._device.services:
+            info = service.get_info()
+            services.append(info)
+        return json.dumps({
+            'root_url': self.base_address,
+            'gateway_xml_url': self.location,
+            'usn': self.usn,
+            'devices': devices,
+            'services': services
+        }, indent=2, default=default_byte)
+
     @defer.inlineCallbacks
     def discover_services(self):
         log.info("querying %s", self.location)
         response = yield treq.get(self.location)
         response_xml = yield response.content()
-        self._device = RootDevice(response_xml)
-        if not self._device.devices or not self._device.services:
-            log.error("failed to parse device: \n%s", response_xml)
+        if not response_xml:
+            log.error("service sent an empty reply\n%s", self.debug_device())
+        try:
+            self._device = RootDevice(response_xml)
+        except Exception as err:
+            log.error("error parsing gateway: %s\n%s\n\n%s", err, self.debug_device(), response_xml)
+            self._device = RootDevice("")
+        log.debug("finished setting up gateway:\n%s", self.debug_device())
 
     @property
     def services(self):

txupnp/scpd.py

@@ -87,7 +87,7 @@ class _SCPDCommand(object):
         xml_response = yield response.content()
         response = self.extract_response(self.extract_body(xml_response))
         if not response:
-            log.error("empty response to %s\n%s", self.method, xml_response)
+            log.debug("empty response to %s\n%s", self.method, xml_response)
         defer.returnValue(response)
 
     @staticmethod
@@ -155,7 +155,7 @@ class SCPDCommandRunner(object):
     @staticmethod
     def _soap_function_info(action_dict):
         if not action_dict.get('argumentList'):
-            log.warning("don't know how to handle argument list: %s", action_dict)
+            log.debug("don't know how to handle argument list: %s", action_dict)
             return (
                 action_dict['name'],
                 [],
@@ -185,7 +185,7 @@ class SCPDCommandRunner(object):
             command._process_result = _return_types(*current._return_types)(command._process_result)
         setattr(command, "__doc__", current.__doc__)
         setattr(self, command.method, command)
-        log.info("registered %s %s", service_type, action_info['name'])
+        log.debug("registered %s %s", service_type, action_info['name'])
 
     def _register_command(self, action_info, service_type):
         try:

txupnp/soap.py

@@ -14,14 +14,14 @@ class SOAPServiceManager(object):
     def __init__(self, reactor):
         self._reactor = reactor
         self.iface_name, self.router_ip, self.lan_address = get_lan_info()
-        self.sspd_factory = SSDPFactory(self.lan_address, self._reactor)
+        self.sspd_factory = SSDPFactory(self._reactor, self.lan_address, self.router_ip)
         self._command_runners = {}
         self._selected_runner = GATEWAY_SCHEMA
 
     @defer.inlineCallbacks
-    def discover_services(self, address=None, ttl=30, max_devices=2):
+    def discover_services(self, address=None, timeout=30, max_devices=1):
         server_infos = yield self.sspd_factory.m_search(
-            address or self.router_ip, ttl=ttl, max_devices=max_devices
+            address or self.router_ip, timeout=timeout, max_devices=max_devices
         )
         locations = []
         for server_info in server_infos:

txupnp/ssdp.py

@@ -1,67 +1,188 @@
 import logging
 import binascii
+import re
 from twisted.internet import defer
 from twisted.internet.protocol import DatagramProtocol
 from txupnp.fault import UPnPError
-from txupnp.constants import GATEWAY_SCHEMA, M_SEARCH_TEMPLATE, SSDP_DISCOVER, SSDP_IP_ADDRESS, SSDP_PORT, SSDP_ALL
+from txupnp.constants import GATEWAY_SCHEMA, SSDP_DISCOVER, SSDP_IP_ADDRESS, SSDP_PORT, SSDP_ALL
 
 log = logging.getLogger(__name__)
 
 
-def parse_http_fields(content_lines):
-    def flatten(s, lower=True):
-        r = s.rstrip(":").rstrip(" ").lstrip(" ").replace("-", "_")
-        if lower:
-            return r.lower()
-        return r
-
-    result = {}
-    for l in content_lines:
-        split = l.decode().split(":")
-        if split and split[0]:
-            k = split[0]
-            v = ":".join(split[1:])
-            result[flatten(k)] = flatten(v, lower=False)
-    return result
-
-    #
-    # return {
-    #     (k.lower().rstrip(":".encode()).replace("-".encode(), "_".encode())).decode(): v.decode()
-    #     for k, v in {
-    #         l.split(": ".encode())[0]: "".encode().join(l.split(": ".encode())[1:])
-    #
-    #     }.items() if k
-    # }
+SSDP_HOST = "%s:%i" % (SSDP_IP_ADDRESS, SSDP_PORT)
+SSDP_BYEBYE = "ssdp:byebye"
+SSDP_UPDATE = "ssdp:update"
+SSDP_ROOT_DEVICE = "upnp:rootdevice"
+line_separator = "\r\n"
 
 
-def parse_ssdp_request(operation, port, protocol, content_lines):
-    if operation != "NOTIFY".encode():
-        log.warning("unsupported operation: %s", operation)
-        raise UPnPError("unsupported operation: %s" % operation)
-    if port != "*".encode():
-        log.warning("unexpected port: %s", port)
-        raise UPnPError("unexpected port: %s" % port)
-    return parse_http_fields(content_lines)
+class SSDPDatagram(object):
+    _M_SEARCH = "M-SEARCH"
+    _NOTIFY = "NOTIFY"
+    _OK = "OK"
 
+    _start_lines = {
+        _M_SEARCH: "M-SEARCH * HTTP/1.1",
+        _NOTIFY: "NOTIFY * HTTP/1.1",
+        _OK: "HTTP/1.1 200 OK"
+    }
 
-def parse_ssdp_response(code, response, content_lines):
-    try:
-        if int(code) != 200:
-            raise UPnPError("unexpected http response code: %i" % int(code))
-    except ValueError:
-        log.error(response)
-        raise UPnPError("unexpected http response code: %s" % code)
-    if response != "OK".encode():
-        raise UPnPError("unexpected response: %s" % response)
-    return parse_http_fields(content_lines)
+    _friendly_names = {
+        _M_SEARCH: "m-search",
+        _NOTIFY: "notify",
+        _OK: "m-search response"
+    }
+
+    _vendor_field_pattern = re.compile("^([\w|\d]*)\.([\w|\d]*\.com):([ \"|\w|\d\:]*)$")
+
+    _patterns = {
+        'host': (re.compile("^(?i)(host):(.*)$"), str),
+        'st': (re.compile("^(?i)(st):(.*)$"), str),
+        'man': (re.compile("^(?i)(man):|(\"(.*)\")$"), str),
+        'mx': (re.compile("^(?i)(mx):(.*)$"), int),
+        'nt': (re.compile("^(?i)(nt):(.*)$"), str),
+        'nts': (re.compile("^(?i)(nts):(.*)$"), str),
+        'usn': (re.compile("^(?i)(usn):(.*)$"), str),
+        'location': (re.compile("^(?i)(location):(.*)$"), str),
+        'cache_control': (re.compile("^(?i)(cache-control):(.*)$"), str),
+        'server': (re.compile("^(?i)(server):(.*)$"), str),
+    }
+
+    _required_fields = {
+        _M_SEARCH: [
+            'host',
+            'st',
+            'man',
+            'mx',
+        ],
+        _OK: [
+            'cache_control',
+            # 'date',
+            # 'ext',
+            'location',
+            'server',
+            'st',
+            'usn'
+        ]
+    }
+
+    _marshallers = {
+        'mx': str,
+        'man': lambda x: ("\"%s\"" % x)
+    }
+
+    def __init__(self, packet_type, host=None, st=None, man=None, mx=None, nt=None, nts=None, usn=None, location=None,
+                 cache_control=None, server=None, date=None, ext=None, **kwargs):
+        if packet_type not in [self._M_SEARCH, self._NOTIFY, self._OK]:
+            raise UPnPError("unknown packet type: {}".format(packet_type))
+        self._packet_type = packet_type
+        self.host = host
+        self.st = st
+        self.man = man
+        self.mx = mx
+        self.nt = nt
+        self.nts = nts
+        self.usn = usn
+        self.location = location
+        self.cache_control = cache_control
+        self.server = server
+        self.date = date
+        self.ext = ext
+        for k, v in kwargs.items():
+            if not k.startswith("_") and hasattr(self, k.lower()) and getattr(self, k.lower()) is None:
+                setattr(self, k.lower(), v)
+
+    def __getitem__(self, item):
+        for i in self._required_fields[self._packet_type]:
+            if i.lower() == item.lower():
+                return getattr(self, i)
+        raise KeyError(item)
+
+    def get_friendly_name(self):
+        return self._friendly_names[self._packet_type]
+
+    def encode(self, trailing_newlines=2):
+        lines = [self._start_lines[self._packet_type]]
+        for attr_name in self._required_fields[self._packet_type]:
+            attr = getattr(self, attr_name)
+            if attr is None:
+                raise UPnPError("required field for {} is missing: {}".format(self._packet_type, attr_name))
+            if attr_name in self._marshallers:
+                value = self._marshallers[attr_name](attr)
+            else:
+                value = attr
+            lines.append("{}: {}".format(attr_name.upper(), value))
+        serialized = line_separator.join(lines)
+        for _ in range(trailing_newlines):
+            serialized += line_separator
+        return serialized
+
+    def as_dict(self):
+        return self._lines_to_content_dict(self.encode().split(line_separator))
+
+    @classmethod
+    def decode(cls, datagram):
+        packet = cls._from_string(datagram.decode())
+        for attr_name in packet._required_fields[packet._packet_type]:
+            attr = getattr(packet, attr_name)
+            if attr is None:
+                raise UPnPError(
+                    "required field for {} is missing from m-search response: {}".format(packet._packet_type, attr_name)
+                )
+        return packet
+
+    @classmethod
+    def _lines_to_content_dict(cls, lines):
+        result = {}
+        for line in lines:
+            if not line:
+                continue
+            matched = False
+            for name, (pattern, field_type) in cls._patterns.items():
+                if name not in result and pattern.findall(line):
+                    match = pattern.findall(line)[-1][-1]
+                    result[name] = field_type(match.lstrip(" ").rstrip(" "))
+                    matched = True
+                    break
+            if not matched:
+                if cls._vendor_field_pattern.findall(line):
+                    match = cls._vendor_field_pattern.findall(line)[-1]
+                    vendor_key = match[0].lstrip(" ").rstrip(" ")
+                    # vendor_domain = match[1].lstrip(" ").rstrip(" ")
+                    value = match[2].lstrip(" ").rstrip(" ")
+                    if vendor_key not in result:
+                        result[vendor_key] = value
+        return result
+
+    @classmethod
+    def _from_string(cls, datagram):
+        lines = [l for l in datagram.split(line_separator) if l]
+        if lines[0] == cls._start_lines[cls._M_SEARCH]:
+            return cls._from_request(lines[1:])
+        if lines[0] == cls._start_lines[cls._NOTIFY]:
+            return cls._from_notify(lines[1:])
+        if lines[0] == cls._start_lines[cls._OK]:
+            return cls._from_response(lines[1:])
+
+    @classmethod
+    def _from_response(cls, lines):
+        return cls(cls._OK, **cls._lines_to_content_dict(lines))
+
+    @classmethod
+    def _from_notify(cls, lines):
+        return cls(cls._NOTIFY, **cls._lines_to_content_dict(lines))
+
+    @classmethod
+    def _from_request(cls, lines):
+        return cls(cls._M_SEARCH, **cls._lines_to_content_dict(lines))
 
 
 class SSDPProtocol(DatagramProtocol):
-    def __init__(self, reactor, finished_deferred, iface, router, ssdp_address=SSDP_IP_ADDRESS,
+    def __init__(self, reactor, iface, router, ssdp_address=SSDP_IP_ADDRESS,
                  ssdp_port=SSDP_PORT, ttl=1, max_devices=None):
         self._reactor = reactor
         self._sem = defer.DeferredSemaphore(1)
-        self.finished_deferred = finished_deferred
+        self.discover_callbacks = {}
         self.iface = iface
         self.router = router
         self.ssdp_address = ssdp_address
@@ -72,93 +193,81 @@ class SSDPProtocol(DatagramProtocol):
         self.devices = []
 
     def startProtocol(self):
-        return self._sem.run(self.do_start)
-
-    def send_m_search(self):
-        data = M_SEARCH_TEMPLATE.format(self.ssdp_address, self.ssdp_port, GATEWAY_SCHEMA, SSDP_ALL, self.ttl)
-        try:
-            log.info("sending m-search (%i bytes) to %s:%i", len(data), self.ssdp_address, self.ssdp_port)
-            self.transport.write(data.encode(), (self.ssdp_address, self.ssdp_port))
-        except Exception as err:
-            log.exception("failed to write %s to %s:%i", binascii.hexlify(data), self.ssdp_address, self.ssdp_port)
-            raise err
-
-    def parse_ssdp_datagram(self, datagram):
-        lines = datagram.split("\r\n".encode())
-        header_pieces = lines[0].split(" ".encode())
-        protocols = {
-            "HTTP/1.1".encode()
-        }
-        operations = {
-            "M-SEARCH".encode(),
-            "NOTIFY".encode()
-        }
-        if header_pieces[0] in operations:
-            if header_pieces[2] not in protocols:
-                raise UPnPError("unknown protocol: %s" % header_pieces[2])
-            return parse_ssdp_request(header_pieces[0], header_pieces[1], header_pieces[2], lines[1:])
-        if header_pieces[0] in protocols:
-            parsed = parse_ssdp_response(header_pieces[1], header_pieces[2], lines[1:])
-            log.info("received reply (%i bytes) to SSDP request (%f) (%s) %s", len(datagram),
-                     self._reactor.seconds() - self._start, parsed['location'], parsed['server'])
-            return parsed
-        raise UPnPError("don't know how to decode datagram: %s" % binascii.hexlify(datagram))
-
-    def do_start(self):
         self._start = self._reactor.seconds()
-        self.finished_deferred.addTimeout(self.ttl, self._reactor)
         self.transport.setTTL(self.ttl)
         self.transport.joinGroup(self.ssdp_address, interface=self.iface)
-        self.send_m_search()
+
+        for st in [SSDP_ALL, SSDP_ROOT_DEVICE, GATEWAY_SCHEMA, GATEWAY_SCHEMA.lower()]:
+            self.send_m_search(service=st)
+
+    def send_m_search(self, service=GATEWAY_SCHEMA):
+        packet = SSDPDatagram(SSDPDatagram._M_SEARCH, host=SSDP_HOST, st=service, man=SSDP_DISCOVER, mx=1)
+        log.debug("writing packet:\n%s", packet.encode())
+        log.info("sending m-search (%i bytes) to %s:%i", len(packet.encode()), self.ssdp_address, self.ssdp_port)
+        try:
+            self.transport.write(packet.encode().encode(), (self.ssdp_address, self.ssdp_port))
+        except Exception as err:
+            log.exception("failed to write %s to %s:%i", binascii.hexlify(packet.encode()), self.ssdp_address, self.ssdp_port)
+            raise err
 
     def leave_group(self):
         self.transport.leaveGroup(self.ssdp_address, interface=self.iface)
 
-    def datagramReceived(self, datagram, addr):
-        self._sem.run(self.handle_datagram, datagram, addr)
-
-    def handle_datagram(self, datagram, address):
-        if address[0] == self.router:
-            try:
-                parsed = self.parse_ssdp_datagram(datagram)
-                self.devices.append(parsed)
-                log.info("found %i/%s so far", len(self.devices), self.max_devices)
-                if not self.finished_deferred.called:
-                    if not self.max_devices or (self.max_devices and len(self.devices) >= self.max_devices):
-                        self._sem.run(self.finished_deferred.callback, self.devices)
-            except UPnPError as err:
-                log.error("error decoding SSDP response from %s:%s (error: %s)\n%s", address[0], address[1], str(err), binascii.hexlify(datagram))
-                raise err
-        elif address[0] != self.iface:
-            log.info("received %i bytes from %s:%i\n%s", len(datagram), address[0], address[1], binascii.hexlify(datagram))
+    def datagramReceived(self, datagram, address):
+        if address[0] == self.iface:
+            return
+        try:
+            packet = SSDPDatagram.decode(datagram)
+            log.debug("decoded %s from %s:%i:\n%s", packet.get_friendly_name(), address[0], address[1], packet.encode())
+        except Exception:
+            log.exception("failed to decode: %s", binascii.hexlify(datagram))
+            return
+        if packet._packet_type == packet._OK:
+            log.info("%s:%i replied to our m-search with new xml url: %s", address[0], address[1], packet.location)
         else:
-            pass  # loopback
+            log.info("%s:%i notified us of a service type: %s", address[0], address[1], packet.st)
+        if packet.st not in map(lambda p: p['st'], self.devices):
+            self.devices.append(packet.as_dict())
+            log.info("%i device%s so far", len(self.devices), "" if len(self.devices) < 2 else "s")
+            if address[0] in self.discover_callbacks:
+                self._sem.run(self.discover_callbacks[address[0]][0], packet)
+
+
+def gather(finished_deferred, max_results):
+    results = []
+
+    def discover_cb(packet):
+        if not finished_deferred.called:
+            results.append(packet.as_dict())
+            if len(results) >= max_results:
+                finished_deferred.callback(results)
+
+    return discover_cb
 
 
 class SSDPFactory(object):
-    def __init__(self, lan_address, reactor):
+    def __init__(self, reactor, lan_address, router_address):
         self.lan_address = lan_address
+        self.router_address = router_address
         self._reactor = reactor
-        self.protocol = None
+        self.protocol = SSDPProtocol(self._reactor, self.lan_address, self.router_address)
         self.port = None
-        self.finished_deferred = defer.Deferred()
 
-    def stop(self):
-        try:
+    def disconnect(self):
+        if self.protocol:
             self.protocol.leave_group()
-            self.port.stopListening()
-        except:
-            pass
+            self.protocol = None
+        if not self.port:
+            return
+        self.port.stopListening()
+        self.port = None
 
-    def connect(self, address, ttl, max_devices=1):
-        self.protocol = SSDPProtocol(self._reactor, self.finished_deferred, self.lan_address, address, ttl=ttl,
-                                     max_devices=max_devices)
+    def connect(self):
+        self._reactor.addSystemEventTrigger("before", "shutdown", self.disconnect)
         self.port = self._reactor.listenMulticast(self.protocol.ssdp_port, self.protocol, listenMultiple=True)
-        self._reactor.addSystemEventTrigger("before", "shutdown", self.stop)
-        return self.finished_deferred
 
     @defer.inlineCallbacks
-    def m_search(self, address, ttl=30, max_devices=2):
+    def m_search(self, address, timeout=30, max_devices=1):
         """
         Perform a HTTP over UDP M-SEARCH query
 
@@ -170,11 +279,18 @@ class SSDPFactory(object):
             'usn': <usn>
         }, ...]
         """
-        d = self.connect(address, ttl, max_devices=max_devices)
+
+        self.connect()
+
+        if address in self.protocol.discover_callbacks:
+            d = self.protocol.discover_callbacks[address][1]
+        else:
+            d = defer.Deferred()
+            d.addTimeout(timeout, self._reactor)
+            found_cb = gather(d, max_devices)
+            self.protocol.discover_callbacks[address] = found_cb, d
         try:
             server_infos = yield d
         except defer.TimeoutError:
             server_infos = self.protocol.devices
-        log.info("found %i devices", len(server_infos))
-        self.stop()
         defer.returnValue(server_infos)

txupnp/tests/test_txupnp.py

@@ -1,3 +1,4 @@
+import sys
 import logging
 from twisted.internet import reactor, defer
 from txupnp.upnp import UPnP
@@ -7,10 +8,12 @@ log = logging.getLogger("txupnp")
 
 
 @defer.inlineCallbacks
-def test(ext_port=4446, int_port=4446, proto='UDP'):
+def test(ext_port=4446, int_port=4446, proto='UDP', timeout=1):
     u = UPnP(reactor)
-    found = yield u.discover()
-    assert found, "M-SEARCH failed to find gateway"
+    found = yield u.discover(timeout=timeout)
+    if not found:
+        print("failed to find gateway")
+        defer.returnValue(None)
     external_ip = yield u.get_external_ip()
     assert external_ip, "Failed to get the external IP"
     log.info(external_ip)
@@ -45,17 +48,22 @@ def test(ext_port=4446, int_port=4446, proto='UDP'):
 
 
 @defer.inlineCallbacks
-def run_tests():
-    for p in ['UDP', 'TCP']:
-        yield test(proto=p)
+def run_tests(timeout=1):
+    for p in ['UDP']:
+        yield test(proto=p, timeout=timeout)
 
 
-def main():
-    d = run_tests()
+def main(timeout):
+    d = run_tests(timeout)
     d.addErrback(log.exception)
     d.addBoth(lambda _: reactor.callLater(0, reactor.stop))
     reactor.run()
 
 
 if __name__ == "__main__":
-    main()
+    if len(sys.argv) > 1:
+        log.setLevel(logging.DEBUG)
+        timeout = int(sys.argv[1])
+    else:
+        timeout = 1
+    main(timeout)

txupnp/upnp.py

@@ -19,7 +19,7 @@ class UPnP(object):
     def commands(self):
         return self.soap_manager.get_runner()
 
-    def m_search(self, address, ttl=30, max_devices=2):
+    def m_search(self, address, timeout=30, max_devices=2):
         """
         Perform a HTTP over UDP M-SEARCH query
 
@@ -31,12 +31,12 @@ class UPnP(object):
             'usn': <usn>
         }, ...]
         """
-        return self.soap_manager.sspd_factory.m_search(address, ttl=ttl, max_devices=max_devices)
+        return self.soap_manager.sspd_factory.m_search(address, timeout=timeout, max_devices=max_devices)
 
     @defer.inlineCallbacks
-    def discover(self, ttl=30, max_devices=2):
+    def discover(self, timeout=1, max_devices=1):
         try:
-            yield self.soap_manager.discover_services(ttl=ttl, max_devices=max_devices)
+            yield self.soap_manager.discover_services(timeout=timeout, max_devices=max_devices)
         except defer.TimeoutError:
             log.warning("failed to find upnp gateway")
             defer.returnValue(False)