Provided by: wsdd_0.7.0-1_all 
NAME
wsdd - A Web Service Discovery host and client daemon.
SYNOPSIS
wsdd [options]
DESCRIPTION
wsdd implements both a Web Service Discovery (WSD) host and a WSD client daemon. The host
implementation enables (Samba) hosts, like your local NAS device, to be found by Web
Service Discovery clients like Windows. The client mode allows searching for other WSD
hosts on the local network.
The default mode of operation is the host mode. The client or discovery mode must be
enabled explictely. Unless configured otherwise, the host mode is always active. Both
modes can be used at the same time.
OPTIONS
General options
-4, --ipv4only
See below.
-6, --ipv6only
Restrict to the given address family. If both options are specified no addreses
will be available and wsdd will exit.
-A, --no-autostart
Do not start networking activities automatically when the program is started. The
API interface (see below) can be used to start and stop the networking activities
while the application is running.
-c DIRECTORY, --chroot DIRECTORY
chroot into the given DIRECTORY after initialization has been performed and right
before the handling of incoming messages starts. The new root directory can be
empty. Consider using the -u option as well.
-h, --help
Show help and exit.
-H HOPLIMIT, --hoplimit HOPLIMIT
Set the hop limit for multicast packets. The default is 1 which should prevent
packets from leaving the local network segment.
-i INTERFACE/ADDRESS, --interface INTERFACE/ADDRESS
Specify on which interfaces wsdd will be listening on. If no interfaces are
specified, all interfaces are used. Loop-back interfaces are never used, even when
explicitly specified. For interfaces with IPv6 addresses, only link-local addresses
will be used for announcing the host on the network. This option can be provided
multiple times in order to restrict traffic to more than one interface. This
option also accepts IP addresses that the service should bind to. For IPv6, only
link local addresses are actually considered as noted above.
-s, --shortlog
Use a shorter logging format that only includes the level and message. This is
useful in cases where the logging mechanism, like systemd on Linux, automatically
prepends a date and process name plus ID to the log message.
-u USER[:GROUP], --user USER[:GROUP]
Change user (and group) when running before handling network packets. Together
with -c this option can be used to increase security if the execution environment,
like the init system, cannot ensure this in another way.
-U UUID, --uuid UUID
The WSD specification requires a device to have a unique address that is stable
across reboots or changes in networks. In the context of the standard, it is
assumed that this is something like a serial number. wsdd uses the UUID version 5
with the DNS namespace and the host name of the local machine as inputs. Thus, the
host name should be stable and not be modified, e.g. by DHCP. However, if you want
wsdd to use a specific UUID you can use this option.
-v, --verbose
Additively increase verbosity of the log output. A single occurrence of
-v/--verbose sets the log level to INFO. More -v options set the log level to
DEBUG.
-V, --version
Show the version number and exit.
Host Mode Options
-d DOMAIN, --domain DOMAIN
Assume that the host running wsdd joined an ADS domain. This will make wsdd report
the host being a domain member. It disables workgroup membership reporting. The
(provided) hostname is automatically converted to lower case. Use the `-p` option
to change this behavior.
-n HOSTNAME, --hostname HOSTNAME
Override the host name wsdd uses during discovery. By default the machine's host
name is used (look at hostname(1)). Only the host name part of a possible FQDN will
be used in the default case.
-o, --no-host
Disable host operation mode. If this option is provided, the host cannot be
discovered by other (Windows) hosts. It can be useful when client/discovery mode is
used and no announcement of the host that runs wsdd should be made.
-p, --preserve-case
Preserve the hostname as it is. Without this option, the hostname is converted as
follows. For workgroup environments (see -w) the hostname is made upper case by
default. Vice versa it is made lower case for usage in domains (see -d).
-t, --no-http
Do not service HTTP requests of the WSD protocol. This option is intended for
debugging purposes where another process may handle the Get messages.
-w WORKGROUP, --workgroup WORKGROUP
By default wsdd reports the host is a member of a workgroup rather than a domain
(use the -d/--domain option to override this). With -w/--workgroup the default
workgroup name can be changed. The default work group name is WORKGROUP. The
(provided) hostname is automatically converted to upper case. Use the `-p` option
to change this behavior.
Client/Discovery Mode Options
-D, --discovery
Enable discovery mode to search for other WSD hosts/servers. Found hosts are logged
with INFO priority. The server interface (see below) can be used for a programatic
interface. Refer to the man page for details of the server interface.
-l PATH/PORT, --listen PATH/PORT
Specify the location of the socket for the server programming interface. If the
option value is numeric, it is interpreted as numeric port for a TCP server port.
Then, the server socket is bound to the localhost only. If the option value is
non-numeric, it is assumed to be a path to UNIX domain socket to which a client can
connect to.
EXAMPLE USAGE
Handle traffic on eth0 and eth2 only, but only with IPv6 addresses
wsdd -i eth0 -i eth2 -6
or
wsdd --interface eth0 --interface eth2 --ipv6only
Set the Workgroup according to smb.conf, be verbose, run with dropped privileges, and change
the root directory to an (empty) directory
SMB_GROUP=$(grep -i '^workgroup=' smb.conf | cut -f2 -d= | tr -d '[:blank:]')
wsdd -v -w $SMB_GROUP -u daemon:daemon -c /var/run/wsdd/chroot
FIREWALL SETUP
Traffic for the following ports, directions and addresses must be allowed:
- Incoming and outgoing traffic to udp/3702 with multicast destination: 239.255.255.250
for IPv4 and ff02::c for IPv6
- Outgoing unicast traffic from udp/3702
- Incoming traffic to tcp/5357
You should further restrict the traffic to the (link-)local subnet, e.g. by using the
`fe80::/10` address space for IPv6. Please note that IGMP traffic must be enabled in order
to get IPv4 multicast traffic working.
API INTERFACE
Wsdd provides a text-based, line-oriented API interface to query information and trigger
actions. The interface can be used with TCP and UNIX domain sockets (see -l/--listen
option). The TCP socket is bound to the local host only. The following commands can be
issued:
clear - Clear list of discovered devices
Clears the list of all discovered devices. Use the probe command to search for devices
again. This command does not return any data and is only available in discover mode.
list - List discovered devices
Returns a tab-separated list of discovered devices with the following information. The
possibly empty list of detected hosts is always terminated with a single dot ('.') in an
otherwise empty line. This command is only available in discover mode.
UUID UUID of the discovered device. Note that a multi-homed device should appear only
once but with multiple addresses (see below)
name The name reported by the device. For discovered Windows hosts, it is the configured
computer name that is reported here.
association
Specifies the domain or workgroup to which the discovered host belongs to. The
type of the association (workgroup or domain) is separated from its value by a
colon.
last_seen
The date and time the device was last seen as a consequence of Probe/Hello messages
provided in ISO8601 with seconds.
addresses
List of all transport addresses that were collected during the discovery process
delimited by commas. Addresses are provided along with the interface (separated by
'%') on which they were discovered. IPv6 addresses are reported on square
brackets. Note that the reported addresses may not match the actual device on which
the device may be reached.
probe [INTERFACE] - Search for devices
Triggers a Probe message on the provided INTERFACE (eth0, e.g.) to search for WSD hosts.
If no interface is provided, all interfaces wsdd listens on are probed. A Probe messages
initiates the discovery message flow. It may take some time for hosts to be actually
discovered. This command does not return any data and is only available in discovery mode.
start - Start networking activities
This command starts the networking acitivies of wsdd if they haven't been started yet.
"Hello" messages are emitted and the host is announced on the network(s) when the host
mode is active. If the discovery mode is enabled a probe process is also started.
stop - Stop networking activities
This is the reverse operation to start. When this command is received, "Bye" messages are
sent in order to notify hosts in the network about the host's disappearance. All
networking sockets used for the WSD protocol are closed as well. Activities can be
restarted with the start operation.
SECURITY
wsdd does not implement any security feature, e.g. by using TLS for the http service. This
is because wsdd's intended usage is within private, i.e. home, LANs. The Hello message
contains the hosts transport address, i.e. the IP address which speeds up discovery
(avoids Resolve message).
KNOWN ISSUES
Using only IPv6 on FreeBSD
If wsdd is running on FreeBSD using IPv6 only, the host running wsdd may not be reliably
discovered. The reason appears to be that Windows is not always able to connect to the
HTTP service for unknown reasons. As a workaround, run wsdd with IPv4 only.
Tunnel/Bridge Interface
If tunnel/bridge interfaces like those created by OpenVPN or Docker exist, they may
interfere with wsdd if executed without providing an interface that it should bind to (so
it binds to all). In such cases, the wsdd hosts appears after wsdd has been started but it
disappears when an update of the Network view in Windows Explorer is forced, either by
refreshing the view or by a reboot of the Windows machine. To solve this issue, the
interface that is connected to the network on which the host should be announced needs to
be specified with the -i/--interface option. This prevents the usage of the tunnel/bridge
interfaces.
Background: Tunnel/bridge interfaces may cause Resolve requests from Windows hosts to be
delivered to wsdd multiple times, i.e. duplicates of such request are created. If wsdd
receives such a request first from a tunnel/bridge it uses the transport address (IP
address) of that interface and sends the response via unicast. Further duplicates are not
processed due to the duplicate message detection which is based on message UUIDs. The
Windows host which receives the response appears to detect a mismatch between the
transport address in the ResolveMatch message (which is the tunnel/bridge address) and the
IP of the sending host/interface (LAN IP, e.g.). Subsequently, the wsdd host is ignored by
Windows.
wsdd(8)