Aggiorna README.md

Introduce WSDD_ARGS to directly pass wsdd arguments.

Dockerfile

@@ -1,9 +1,10 @@
 FROM python:3-alpine
 
 WORKDIR /usr/src/app
-
-RUN apk add --no-cache curl bash && curl https://raw.githubusercontent.com/christgau/wsdd/v0.7.0/src/wsdd.py -o wsdd.py && apk del curl
-
-copy docker-cmd.sh .
+RUN apk update
+RUN apk upgrade
+RUN apk add bash
+COPY wsdd.py .
+COPY docker-cmd.sh .
 
 CMD [ "./docker-cmd.sh"]

README.md

@@ -1,14 +1,40 @@
+# FABIO note
+clonare git ed entrare nel folder
+```
+git clone https://forgit.patachina.duckdns.org/Fabio/wsdd-docker.git
+cd wsdd-docker
+```
+creare l'immagine docker wsdd con il comando
+``` 
+sudo docker build -t wsdd .
+``` 
+per far partire il docker usare il seguente docker compose
+in HOSTNAME= mettere il nome che si vuole visualizzare nella rete
+
+``` docker compose
+services:
+  wsdd:
+    image: wsdd:latest    
+    network_mode: host
+    environment:
+      - 'HOSTNAME=OrangePiSMB'
+    restart: unless-stopped
+``` 
+original git https://github.com/JonasPed/wsdd-docker e https://github.com/nitmir/wsdd (multiple hosts)
+
 # wsdd-docker
 Docker image for wsdd.py. 
 
 wsdd implements a Web Service Discovery host daemon. This enables (Samba) hosts, like your local NAS device or Linux server, to be found by Web Service Discovery Clients like Windows.
 
 ## Supported environment variables
-HOSTNAME: Samba Netbios name to report.
+`HOSTNAME`: Samba Netbios name to report.
 
-WORKGROUP: Workgroup name
+`WORKGROUP`: Workgroup name
 
-DOMAIN: Report being a member of an AD DOMAIN. Disables WORKGROUP if set. 
+`DOMAIN`: Report being a member of an AD DOMAIN. Disables `WORKGROUP` if set.
+
+Alternatively, you can pass all desired wsdd arguments in the environment variable `WSDD_ARGS`. In this case, the arguments are passed as-is and all other environment variables are ignored.
 
 ## Running container
 ### From command line

docker-cmd.sh

@@ -1,23 +1,24 @@
 #!/usr/bin/env bash
 
-args=( )
+args=
 
+if [ ! -z "${WSDD_ARGS}" ]; then
+  args=${WSDD_ARGS}
+else
 	if [ ! -z "${HOSTNAME}" ]; then
-	args+=( "-n $HOSTNAME ")
+		args+="-n $HOSTNAME "
 	else
 		echo "HOSTNAME environment variable must be set."
 		exit 1
 	fi
 
 	if  [ ! -z "${WORKGROUP}" ]; then
-	args+=( "-w $WORKGROUP " )
+		args+="-w $WORKGROUP "
 	fi
 
 	if  [ ! -z "${DOMAIN}" ]; then
-	args+=( "-d $DOMAIN " )
+		args+="-d $DOMAIN "
+	fi
 fi
 
-
-
 exec python wsdd.py ${args}
-

wsdd.py

@@ -0,0 +1,787 @@
+#!/usr/bin/env python3
+
+# Implements a target service according to the Web Service Discovery
+# specification.
+#
+# The purpose is to enable non-Windows devices to be found by the 'Network
+# (Neighborhood)' from Windows machines.
+#
+# see http://specs.xmlsoap.org/ws/2005/04/discovery/ws-discovery.pdf and
+# related documents for details (look at README for more references)
+#
+# (c) Steffen Christgau, 2017-2019
+
+import sys
+import signal
+import socket
+import selectors
+import struct
+import argparse
+import uuid
+import time
+import random
+import logging
+import platform
+import ctypes.util
+import collections
+import xml.etree.ElementTree as ElementTree
+import http.server
+
+
+# sockaddr C type, with a larger data field to capture IPv6 addresses
+# unfortunately, the structures differ on Linux and FreeBSD
+if platform.system() == 'Linux':
+    class sockaddr(ctypes.Structure):
+        _fields_ = [('family', ctypes.c_uint16),
+                    ('data', ctypes.c_uint8 * 24)]
+else:
+    class sockaddr(ctypes.Structure):
+        _fields_ = [('length', ctypes.c_uint8),
+                    ('family', ctypes.c_uint8),
+                    ('data', ctypes.c_uint8 * 24)]
+
+
+class if_addrs(ctypes.Structure):
+    pass
+
+
+if_addrs._fields_ = [('next', ctypes.POINTER(if_addrs)),
+                     ('name', ctypes.c_char_p),
+                     ('flags', ctypes.c_uint),
+                     ('addr', ctypes.POINTER(sockaddr)),
+                     ('netmask', ctypes.POINTER(sockaddr))]
+
+
+class HTTPv6Server(http.server.HTTPServer):
+    """Simple HTTP server with IPv6 support"""
+    address_family = socket.AF_INET6
+
+    def server_bind(self):
+        self.socket.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
+        super().server_bind()
+
+
+class MulticastInterface:
+    """
+    A class for handling multicast traffic on a given interface for a
+    given address family. It provides multicast sender and receiver sockets
+    """
+    def __init__(self, family, address, intf_name):
+        self.address = address
+        self.family = family
+        self.interface = intf_name
+        self.recv_socket = socket.socket(self.family, socket.SOCK_DGRAM)
+        self.recv_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        self.send_socket = socket.socket(self.family, socket.SOCK_DGRAM)
+        self.transport_address = address
+        self.multicast_address = None
+        self.listen_address = None
+
+        if family == socket.AF_INET:
+            self.init_v4()
+        elif family == socket.AF_INET6:
+            self.init_v6()
+
+        logger.info('joined multicast group {0} on {2}%{1}'.format(
+            self.multicast_address, self.interface, self.address))
+        logger.debug('transport address on {0} is {1}'.format(
+            self.interface, self.transport_address))
+        logger.debug('will listen for HTTP traffic on address {0}'.format(
+            self.listen_address))
+
+    def init_v6(self):
+        idx = socket.if_nametoindex(self.interface)
+        self.multicast_address = (WSD_MCAST_GRP_V6, WSD_UDP_PORT, 0x575C, idx)
+
+        # v6: member_request = { multicast_addr, intf_idx }
+        mreq = (
+            socket.inet_pton(self.family, WSD_MCAST_GRP_V6) +
+            struct.pack('@I', idx))
+        self.recv_socket.setsockopt(
+            socket.IPPROTO_IPV6, socket.IPV6_JOIN_GROUP, mreq)
+        self.recv_socket.setsockopt(
+            socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
+
+        # bind to network interface, i.e. scope and handle OS differences,
+        # see Stevens: Unix Network Programming, Section 21.6, last paragraph
+        try:
+            self.recv_socket.bind((WSD_MCAST_GRP_V6, WSD_UDP_PORT, 0, idx))
+        except OSError:
+            self.recv_socket.bind(('::', 0, 0, idx))
+
+        self.send_socket.setsockopt(
+            socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_LOOP, 0)
+        self.send_socket.setsockopt(
+            socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_HOPS, args.hoplimit)
+        self.send_socket.setsockopt(
+            socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_IF, idx)
+
+        self.transport_address = '[{0}]'.format(self.address)
+        self.listen_address = (self.address, WSD_HTTP_PORT, 0, idx)
+
+    def init_v4(self):
+        idx = socket.if_nametoindex(self.interface)
+        self.multicast_address = (WSD_MCAST_GRP_V4, WSD_UDP_PORT)
+
+        # v4: member_request (ip_mreqn) = { multicast_addr, intf_addr, idx }
+        mreq = (
+            socket.inet_pton(self.family, WSD_MCAST_GRP_V4) +
+            socket.inet_pton(self.family, self.address) +
+            struct.pack('@I', idx))
+        self.recv_socket.setsockopt(
+            socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)
+
+        try:
+            self.recv_socket.bind((WSD_MCAST_GRP_V4, WSD_UDP_PORT))
+        except OSError:
+            self.recv_socket.bind(('', WSD_UDP_PORT))
+
+        self.send_socket.setsockopt(
+            socket.IPPROTO_IP, socket.IP_MULTICAST_IF, mreq)
+        self.send_socket.setsockopt(
+            socket.IPPROTO_IP, socket.IP_MULTICAST_LOOP, 0)
+        self.send_socket.setsockopt(
+            socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, args.hoplimit)
+
+        self.listen_address = (self.address, WSD_HTTP_PORT)
+
+
+# constants for WSD XML/SOAP parsing
+WSA_URI = 'http://schemas.xmlsoap.org/ws/2004/08/addressing'
+WSD_URI = 'http://schemas.xmlsoap.org/ws/2005/04/discovery'
+WSDP_URI = 'http://schemas.xmlsoap.org/ws/2006/02/devprof'
+
+namespaces = {
+    'soap': 'http://www.w3.org/2003/05/soap-envelope',
+    'wsa': WSA_URI,
+    'wsd': WSD_URI,
+    'wsx': 'http://schemas.xmlsoap.org/ws/2004/09/mex',
+    'wsdp': WSDP_URI,
+    'pnpx': 'http://schemas.microsoft.com/windows/pnpx/2005/10',
+    'pub': 'http://schemas.microsoft.com/windows/pub/2005/07'
+}
+
+WSD_MAX_KNOWN_MESSAGES = 10
+
+WSD_PROBE = WSD_URI + '/Probe'
+WSD_PROBE_MATCH = WSD_URI + '/ProbeMatches'
+WSD_RESOLVE = WSD_URI + '/Resolve'
+WSD_RESOLVE_MATCH = WSD_URI + '/ResolveMatches'
+WSD_HELLO = WSD_URI + '/Hello'
+WSD_BYE = WSD_URI + '/Bye'
+WSD_GET = 'http://schemas.xmlsoap.org/ws/2004/09/transfer/Get'
+WSD_GET_RESPONSE = 'http://schemas.xmlsoap.org/ws/2004/09/transfer/GetResponse'
+
+WSD_TYPE_DEVICE = 'wsdp:Device'
+PUB_COMPUTER = 'pub:Computer'
+WSD_TYPE_DEVICE_COMPUTER = '{0} {1}'.format(WSD_TYPE_DEVICE, PUB_COMPUTER)
+
+WSD_MCAST_GRP_V4 = '239.255.255.250'
+WSD_MCAST_GRP_V6 = 'ff02::c'  # link-local
+
+WSA_ANON = WSA_URI + '/role/anonymous'
+WSA_DISCOVERY = 'urn:schemas-xmlsoap-org:ws:2005:04:discovery'
+
+# protocol assignments (WSD spec/Section 2.4)
+WSD_UDP_PORT = 3702
+WSD_HTTP_PORT = 5357
+WSD_MAX_LEN = 32767
+
+# SOAP/UDP transmission constants
+MULTICAST_UDP_REPEAT = 4
+UNICAST_UDP_REPEAT = 2
+UDP_MIN_DELAY = 50
+UDP_MAX_DELAY = 250
+UDP_UPPER_DELAY = 500
+
+# some globals
+wsd_known_messages = collections.deque([])
+wsd_message_number = 1
+wsd_instance_id = int(time.time())
+send_queue = []
+
+args = None
+logger = None
+
+
+# shortcuts for building WSD responses
+def wsd_add_metadata_version(parent):
+    meta_data = ElementTree.SubElement(parent, 'wsd:MetadataVersion')
+    meta_data.text = '1'
+
+
+def wsd_add_types(parent):
+    dev_type = ElementTree.SubElement(parent, 'wsd:Types')
+    dev_type.text = WSD_TYPE_DEVICE_COMPUTER
+
+
+def wsd_add_endpoint_reference(uuid_, parent):
+    endpoint = ElementTree.SubElement(parent, 'wsa:EndpointReference')
+    address = ElementTree.SubElement(endpoint, 'wsa:Address')
+    address.text = uuid_.urn
+
+
+def wsd_add_xaddr(uuid_, parent, transport_addr):
+    if transport_addr:
+        item = ElementTree.SubElement(parent, 'wsd:XAddrs')
+        item.text = 'http://{0}:{1}/{2}'.format(
+            transport_addr, WSD_HTTP_PORT, uuid_)
+
+
+def wsd_build_message(to_addr, action_str, request_header, response):
+    """
+    Build a WSD message with a given action string including SOAP header.
+
+    The message can be constructed based on a response to another
+    message (given by its header) and with a optional response that
+    serves as the message's body
+    """
+    global wsd_message_number
+
+    env = ElementTree.Element('soap:Envelope')
+    header = ElementTree.SubElement(env, 'soap:Header')
+
+    to = ElementTree.SubElement(header, 'wsa:To')
+    to.text = to_addr
+
+    action = ElementTree.SubElement(header, 'wsa:Action')
+    action.text = action_str
+
+    msg_id = ElementTree.SubElement(header, 'wsa:MessageID')
+    msg_id.text = uuid.uuid1().urn
+
+    if request_header:
+        req_msg_id = request_header.find('./wsa:MessageID', namespaces)
+        if req_msg_id is not None:
+            relates_to = ElementTree.SubElement(header, 'wsa:RelatesTo')
+            relates_to.text = req_msg_id.text
+
+    seq = ElementTree.SubElement(header, 'wsd:AppSequence', {
+        'InstanceId': str(wsd_instance_id),
+        'SequenceId': uuid.uuid1().urn,
+        'MessageNumber': str(wsd_message_number)})
+    wsd_message_number = wsd_message_number + 1
+
+    body = ElementTree.SubElement(env, 'soap:Body')
+    body.append(response)
+
+    for prefix, uri in namespaces.items():
+        env.attrib['xmlns:' + prefix] = uri
+
+    xml = b'<?xml version="1.0" encoding="utf-8"?>'
+    xml = xml + ElementTree.tostring(env, encoding='utf-8')
+
+    logger.debug('constructed xml for WSD message: {0}'.format(xml))
+
+    return xml
+
+
+# WSD message type handling
+def wsd_handle_probe(uuid_, probe):
+    scopes = probe.find('./wsd:Scopes', namespaces)
+
+    if scopes:
+        # THINK: send fault message (see p. 21 in WSD)
+        logger.warn('Scopes are not supported but were probed ({}).'.format(
+            scopes))
+        return None
+
+    types_elem = probe.find('./wsd:Types', namespaces)
+    if types_elem is None:
+        logger.debug('Probe message lacks wsd:Types element. Ignored.')
+        return None
+
+    types = types_elem.text
+    if not types == WSD_TYPE_DEVICE:
+        logger.debug('unknown discovery type ({0}) during probe'.format(types))
+        return None
+
+    matches = ElementTree.Element('wsd:ProbeMatches')
+    match = ElementTree.SubElement(matches, 'wsd:ProbeMatch')
+    wsd_add_endpoint_reference(uuid_, match)
+    wsd_add_types(match)
+    wsd_add_metadata_version(match)
+
+    return matches
+
+
+def wsd_handle_resolve(resolve, xaddr):
+    addr = resolve.find('./wsa:EndpointReference/wsa:Address', namespaces)
+    if addr is None:
+        logger.debug('invalid resolve request: missing endpoint address')
+        return None
+
+    if addr.text not in args.urn2uuid:
+        logger.debug(('invalid resolve request: address ({}) does not match '
+                      'own one ({})').format(addr.text, args.uuid))
+        return None
+    uuid_ = args.urn2uuid[addr.text]
+    matches = ElementTree.Element('wsd:ResolveMatches')
+    match = ElementTree.SubElement(matches, 'wsd:ResolveMatch')
+    wsd_add_endpoint_reference(uuid_, match)
+    wsd_add_types(match)
+    wsd_add_xaddr(uuid_, match, xaddr)
+    wsd_add_metadata_version(match)
+
+    return matches
+
+
+def wsd_handle_get(uuid_, hostname):
+    # see https://msdn.microsoft.com/en-us/library/hh441784.aspx for an example
+    metadata = ElementTree.Element('wsx:Metadata')
+    section = ElementTree.SubElement(metadata, 'wsx:MetadataSection', {
+        'Dialect': WSDP_URI + '/ThisDevice'})
+    device = ElementTree.SubElement(section, 'wsdp:ThisDevice')
+    ElementTree.SubElement(device, 'wsdp:FriendlyName').text = (
+            'WSD Device {0}'.format(hostname))
+    ElementTree.SubElement(device, 'wsdp:FirmwareVersion').text = '1.0'
+    ElementTree.SubElement(device, 'wsdp:SerialNumber').text = '1'
+
+    section = ElementTree.SubElement(metadata, 'wsx:MetadataSection', {
+        'Dialect': WSDP_URI + '/ThisModel'})
+    model = ElementTree.SubElement(section, 'wsdp:ThisModel')
+    ElementTree.SubElement(model, 'wsdp:Manufacturer').text = 'wsdd'
+    ElementTree.SubElement(model, 'wsdp:ModelName').text = 'wsdd'
+    ElementTree.SubElement(model, 'pnpx:DeviceCategory').text = 'Computers'
+
+    section = ElementTree.SubElement(metadata, 'wsx:MetadataSection', {
+        'Dialect': WSDP_URI + '/Relationship'})
+    rel = ElementTree.SubElement(section, 'wsdp:Relationship', {
+        'Type': WSDP_URI + '/host'})
+    host = ElementTree.SubElement(rel, 'wsdp:Host')
+    wsd_add_endpoint_reference(uuid_, host)
+    ElementTree.SubElement(host, 'wsdp:Types').text = PUB_COMPUTER
+    ElementTree.SubElement(host, 'wsdp:ServiceId').text = uuid_.urn
+    if args.domain:
+        ElementTree.SubElement(host, PUB_COMPUTER).text = (
+            '{0}/Domain:{1}'.format(
+                hostname if args.preserve_case else hostname.lower(),
+                args.domain))
+    else:
+        ElementTree.SubElement(host, PUB_COMPUTER).text = (
+            '{0}/Workgroup:{1}'.format(
+                hostname if args.preserve_case else hostname.upper(),
+                args.workgroup.upper()))
+
+    return metadata
+
+
+def wsd_is_duplicated_msg(msg_id):
+    """
+    Check for a duplicated message.
+
+    Implements SOAP-over-UDP Appendix II Item 2
+    """
+    if msg_id in wsd_known_messages:
+        return True
+
+    wsd_known_messages.append(msg_id)
+    if len(wsd_known_messages) > WSD_MAX_KNOWN_MESSAGES:
+        wsd_known_messages.popleft()
+
+    return False
+
+
+def wsd_handle_message(data, interface, src_address):
+    """
+    handle a WSD message that might be received by a MulticastInterface class
+    """
+    tree = ElementTree.fromstring(data)
+    header = tree.find('./soap:Header', namespaces)
+    msg_id = header.find('./wsa:MessageID', namespaces).text
+    urn = header.find('./wsa:To', namespaces).text
+    try:
+        uuid_ = args.urn2uuid[urn]
+    except KeyError:
+        if urn in ['urn:schemas-xmlsoap-org:ws:2005:04:discovery']:
+            urn = None
+        else:
+            logger.debug('Go unknown wsa:To: {}'.format(data))
+
+    # if message came over multicast interface, check for duplicates
+    if interface and wsd_is_duplicated_msg(msg_id):
+        logger.debug('known message ({0}): dropping it'.format(msg_id))
+        return []
+
+    response = None
+    action = header.find('./wsa:Action', namespaces).text
+    body = tree.find('./soap:Body', namespaces)
+    _, _, action_method = action.rpartition('/')
+
+    if interface:
+        logger.info('{}:{}({}) - - "{} {} UDP" - -'.format(
+            src_address[0], src_address[1], interface.interface,
+            action_method, msg_id
+        ))
+    else:
+        # http logging is already done by according server
+        logger.debug('processing WSD {} message ({})'.format(
+            action_method, msg_id))
+
+    logger.debug('incoming message content is {0}'.format(data))
+    if action == WSD_PROBE:
+        probe = body.find('./wsd:Probe', namespaces)
+        responses = []
+        for uuid_ in args.uuid:
+            response = wsd_handle_probe(uuid_, probe)
+            if response:
+                responses.append(
+                    wsd_build_message(WSA_ANON, WSD_PROBE_MATCH, header, response)
+                )
+        return responses
+    elif action == WSD_RESOLVE:
+        resolve = body.find('./wsd:Resolve', namespaces)
+        response = wsd_handle_resolve(resolve, interface.transport_address)
+        if response:
+            return [wsd_build_message(WSA_ANON, WSD_RESOLVE_MATCH, header, response)]
+        else:
+            return []
+    elif action == WSD_GET:
+        uuid_ = args.urn2uuid[urn]
+        hostname = args.uuid2hostname[str(uuid_)]
+        return [wsd_build_message(
+            WSA_ANON,
+            WSD_GET_RESPONSE,
+            header,
+            wsd_handle_get(uuid_, hostname))]
+    else:
+        logger.debug('unhandled action {0}/{1}'.format(action, msg_id))
+        return []
+
+
+class WSDUdpRequestHandler():
+    """Class for handling WSD requests coming from UDP datagrams."""
+    def __init__(self, interface):
+        self.interface = interface
+
+    def handle_request(self):
+        msg, address = self.interface.recv_socket.recvfrom(WSD_MAX_LEN)
+        msgs = wsd_handle_message(msg, self.interface, address)
+        for msg in msgs:
+            self.enqueue_datagram(msg, address=address)
+
+    def send_hello(self, uuid_):
+        """WS-Discovery, Section 4.1, Hello message"""
+        hello = ElementTree.Element('wsd:Hello')
+        wsd_add_endpoint_reference(uuid_, hello)
+        # THINK: Microsoft does not send the transport address here due
+        # to privacy reasons. Could make this optional.
+        wsd_add_xaddr(uuid_, hello, self.interface.transport_address)
+        wsd_add_metadata_version(hello)
+
+        msg = wsd_build_message(WSA_DISCOVERY, WSD_HELLO, None, hello)
+        self.enqueue_datagram(msg, msg_type='Hello')
+
+    def send_bye(self, uuid_):
+        """WS-Discovery, Section 4.2, Bye message"""
+        bye = ElementTree.Element('wsd:Bye')
+        wsd_add_endpoint_reference(uuid_, bye)
+
+        msg = wsd_build_message(WSA_DISCOVERY, WSD_BYE, None, bye)
+        self.enqueue_datagram(msg, msg_type='Bye')
+
+    def enqueue_datagram(self, msg, address=None, msg_type=None):
+        """
+        Add an outgoing WSD (SOAP) message to the queue of outstanding messages
+
+        Implements SOAP over UDP, Appendix I.
+        """
+        if not address:
+            address = self.interface.multicast_address
+
+        if msg_type:
+            logger.debug('scheduling {0} message via {1} to {2}'.format(
+                msg_type, self.interface.interface, address))
+
+        msg_count = (
+            MULTICAST_UDP_REPEAT
+            if address == self.interface.multicast_address
+            else UNICAST_UDP_REPEAT)
+
+        due_time = time.time()
+        t = random.randint(UDP_MIN_DELAY, UDP_MAX_DELAY)
+        for i in range(msg_count):
+            send_queue.append([due_time, self.interface, address, msg])
+            due_time += t / 1000
+            t = min(t * 2, UDP_UPPER_DELAY)
+
+
+class WSDHttpRequestHandler(http.server.BaseHTTPRequestHandler):
+    """Class for handling WSD requests coming over HTTP"""
+    def log_message(self, fmt, *args):
+        logger.info("{} - - ".format(self.address_string()) + fmt % args)
+
+    def do_POST(s):
+        uuid_ = s.path.strip('/')
+        if not uuid_ in args.uuid2hostname:
+            s.send_error(404)
+
+        if s.headers['Content-Type'] != 'application/soap+xml':
+            s.send_error(400, 'Invalid Content-Type')
+
+        content_length = int(s.headers['Content-Length'])
+        body = s.rfile.read(content_length)
+
+        responses = wsd_handle_message(body, None, None)
+        if len(responses) == 1:
+            s.send_response(200)
+            s.send_header('Content-Type', 'application/soap+xml')
+            s.end_headers()
+            s.wfile.write(responses[0])
+        else:
+            s.send_error(500)
+
+
+def enumerate_host_interfaces():
+    """Get all addresses of all installed interfaces, except loopback"""
+    libc = ctypes.CDLL(ctypes.util.find_library('c'), use_errno=True)
+    addr = ctypes.POINTER(if_addrs)()
+    retval = libc.getifaddrs(ctypes.byref(addr))
+    if retval:
+        raise OSError(ctypes.get_errno())
+
+    addrs = []
+    ptr = addr
+    while ptr:
+        deref = ptr[0]
+        family = deref.addr[0].family if deref.addr else None
+        if family == socket.AF_INET:
+            addrs.append((
+                deref.name.decode(), family,
+                socket.inet_ntop(family, bytes(deref.addr[0].data[2:6]))))
+        elif family == socket.AF_INET6:
+            if bytes(deref.addr[0].data[6:8]) == b'\xfe\x80':
+                addrs.append((
+                    deref.name.decode(), family,
+                    socket.inet_ntop(family, bytes(deref.addr[0].data[6:22]))))
+
+        ptr = deref.next
+
+    libc.freeifaddrs(addr)
+
+    # filter detected addresses by command line arguments,
+    # always exclude 'lo' interface
+    if args.ipv4only:
+        addrs = [x for x in addrs if x[1] == socket.AF_INET]
+
+    if args.ipv6only:
+        addrs = [x for x in addrs if x[1] == socket.AF_INET6]
+
+    addrs = [x for x in addrs if not x[0].startswith('lo')]
+    if args.interface:
+        addrs = [x for x in addrs if x[0] in args.interface]
+
+    return addrs
+
+
+def sigterm_handler(signum, frame):
+    if signum == signal.SIGTERM:
+        logger.info('received SIGTERM, tearing down')
+        # implictely raise SystemExit to cleanup properly
+        sys.exit(0)
+
+
+def parse_args():
+    global args, logger
+
+    parser = argparse.ArgumentParser()
+
+    parser.add_argument(
+        '-i', '--interface',
+        help='interface address to use',
+        action='append', default=[])
+    parser.add_argument(
+        '-H', '--hoplimit',
+        help='hop limit for multicast packets (default = 1)', type=int,
+        default=1)
+    parser.add_argument(
+        '-u', '--uuid',
+        help='UUID for the target device',
+        default=None,
+        nargs='*'
+    )
+    parser.add_argument(
+        '-v', '--verbose',
+        help='increase verbosity',
+        action='count', default=0)
+    parser.add_argument(
+        '-d', '--domain',
+        help='set domain name (disables workgroup)',
+        default=None,
+    )
+    parser.add_argument(
+        '-n', '--hostname',
+        help='override (NetBIOS) hostname to be used (default hostname)',
+        nargs='*')
+    parser.add_argument(
+        '-w', '--workgroup',
+        help='set workgroup name (default WORKGROUP)',
+        default='WORKGROUP')
+    parser.add_argument(
+        '-t', '--nohttp',
+        help='disable http service (for debugging, e.g.)',
+        action='store_true')
+    parser.add_argument(
+        '-4', '--ipv4only',
+        help='use only IPv4 (default = off)',
+        action='store_true')
+    parser.add_argument(
+        '-6', '--ipv6only',
+        help='use IPv6 (default = off)',
+        action='store_true')
+    parser.add_argument(
+        '-s', '--shortlog',
+        help='log only level and message',
+        action='store_true')
+    parser.add_argument(
+        '-p', '--preserve-case',
+        help='preserve case of the provided/detected hostname',
+        action='store_true')
+
+    args = parser.parse_args(sys.argv[1:])
+
+    if args.verbose == 1:
+        log_level = logging.INFO
+    elif args.verbose > 1:
+        log_level = logging.DEBUG
+    else:
+        log_level = logging.WARNING
+
+    if args.shortlog:
+        fmt = '%(levelname)s: %(message)s'
+    else:
+        fmt = ('%(asctime)s:%(name)s %(levelname)s(pid %(process)d): '
+               '%(message)s')
+
+    logging.basicConfig(level=log_level, format=fmt)
+    logger = logging.getLogger('wsdd')
+
+    if not args.interface:
+        logger.warning('no interface given, using all interfaces')
+
+    if not args.hostname:
+        args.hostname.append(socket.gethostname().partition('.')[0])
+
+    if not args.uuid:
+        args.uuid = [uuid.uuid5(uuid.NAMESPACE_DNS, hostname) for hostname in args.hostname]
+        logger.info('using pre-defined UUID {0}'.format(str(args.uuid)))
+    else:
+        if len(args.uuid) != len(args.hostname):
+            raise ValueError("please give the same number of uuid and hostname")
+        args.uuid = [uuid.UUID(uuid_) for uuid_ in args.uuid]
+        logger.info('user-supplied device UUID is {0}'.format(str(args.uuid)))
+    args.uuid2hostname = {str(uuid_): hostname for uuid_, hostname in zip(args.uuid, args.hostname)}
+    args.urn2uuid = {uuid_.urn: uuid_ for uuid_ in args.uuid}
+    args.hostname2uuid = {hostname: uuid_ for uuid_, hostname in zip(args.uuid, args.hostname)}
+
+    for prefix, uri in namespaces.items():
+        ElementTree.register_namespace(prefix, uri)
+
+
+def send_outstanding_messages(block=False):
+    """
+    Send all queued datagrams for which the timeout has been reached. If block
+    is true then all queued messages will be sent but with their according
+    delay.
+    """
+    if len(send_queue) == 0:
+        return None
+
+    # reverse ordering for faster removal of the last element
+    send_queue.sort(key=lambda x: x[0], reverse=True)
+
+    # Emit every message that is "too late". Note that in case the system
+    # time jumps forward, multiple outstanding message which have a
+    # delay between them are sent out without that delay.
+    now = time.time()
+    while len(send_queue) > 0 and (send_queue[-1][0] <= now or block):
+        interface = send_queue[-1][1]
+        addr = send_queue[-1][2]
+        msg = send_queue[-1][3]
+        try:
+            interface.send_socket.sendto(msg, addr)
+        except Exception as e:
+            logger.error('error while sending packet on {}: {}'.format(
+                interface.interface, e))
+
+        del send_queue[-1]
+        if block and len(send_queue) > 0:
+            delay = send_queue[-1][0] - now
+            if delay > 0:
+                time.sleep(delay)
+                now = time.time()
+
+    if len(send_queue) > 0 and not block:
+        return send_queue[-1][0] - now
+
+    return None
+
+
+def serve_wsd_requests(addresses):
+    """
+    Multicast handling: send Hello message on startup, receive from multicast
+    sockets and handle the messages, and emit Bye message when process gets
+    terminated by signal
+    """
+    s = selectors.DefaultSelector()
+    udp_srvs = []
+
+    for address in addresses:
+        interface = MulticastInterface(address[1], address[2], address[0])
+        udp_srv = WSDUdpRequestHandler(interface)
+        udp_srvs.append(udp_srv)
+        s.register(interface.recv_socket, selectors.EVENT_READ, udp_srv)
+
+        if not args.nohttp:
+            klass = (
+                http.server.HTTPServer
+                if interface.family == socket.AF_INET
+                else HTTPv6Server)
+            http_srv = klass(interface.listen_address, WSDHttpRequestHandler)
+            s.register(http_srv.fileno(), selectors.EVENT_READ, http_srv)
+
+    # everything is set up, announce ourself and serve requests
+    try:
+        for srv in udp_srvs:
+            for uuid_ in args.uuid:
+                srv.send_hello(uuid_)
+
+        while True:
+            try:
+                timeout = send_outstanding_messages()
+                events = s.select(timeout)
+                for key, mask in events:
+                    key.data.handle_request()
+            except (SystemExit, KeyboardInterrupt):
+                # silently exit the loop
+                logger.debug('got termination signal')
+                break
+            except Exception:
+                logger.exception('error in main loop')
+    finally:
+        logger.info('shutting down gracefully...')
+
+    # say goodbye
+    for srv in udp_srvs:
+        for uuid_ in args.uuid:
+            srv.send_bye(uuid_)
+
+    send_outstanding_messages(True)
+
+
+def main():
+    parse_args()
+
+    addresses = enumerate_host_interfaces()
+    if not addresses:
+        logger.error("No multicast addresses available. Exiting.")
+        return 1
+
+    signal.signal(signal.SIGTERM, sigterm_handler)
+    serve_wsd_requests(addresses)
+    logger.info('Done.')
+    return 0
+
+
+if __name__ == '__main__':
+    sys.exit(main())