SSDP Responder for Linux/UNIX

Simple Service Discovery Protocol daemon (SSDP) for networked Linux and UNIX devices. Useful in any setup, big or small, but targeted more at embedded systems that need to announce themselves to Windows systems.

ssdpd is a stand-alone UNIX daemon with no external dependencies but the standard C library. It has a built-in web server for serving the UPnP XML description which Windows use to present the icon, by default an InternetGatewayDevice is announced.

Also included is the ssdp-scan tool, which continuously scans for SSDP capable hosts on the network. Take care only to use this for debugging since it scans the network quite aggressively.

Note: when ssdpd is started as root it will drop privileges as soon as it has created its UUID cache and PID file. It is recommended to have a dedicated ssdp user (and group) available in the system for this purpose. As a fallback, user nobody (and nogroup) is used. When started as non-root, make sure to provide a path for the cache file with the -c FILE option.

Usage

Usage: ssdpd [-hnsvw] [-c FILE] [-d URL] [-i SEC] [-l LEVEL] [-m NAME] [-M URL]
                      [-p URL] [-P FILE] [-r SEC] [-R NUM] [-t TTL] [-u UUID]
                      [IFACE [IFACE ...]]

    -c FILE   Path to alternate ssdpd.cache to store and/or read the UUID
    -d URL    Override UPnP description.xml URL in announcements.  The '%s' in
              the URL is replaced with the IP, e.g. https://%s:1901/main.xml
    -h        This help text
    -i SEC    SSDP notify interval (30-900), default 300 sec
    -l LVL    Set log level: none, err, notice (default), info, debug
    -m NAME   Override manufacturer in the default description.xml
    -M URL    Override manufacturerURL in the default description.xml
    -n        Run in foreground, do not daemonize by default
    -r SEC    Interface refresh interval (5-1800), default 600 sec
    -R NUM    Initial retries, using 10 sec refresh interval, default 3 times
    -p URL    Override presentationURL (WebUI) in the default description.xml
              The '%s' is replaced with the IP address.  Default: http://%s/
    -P FILE   Override PID file location, absolute path required
    -s        Use syslog, default unless running in foreground, -n
    -t TTL    TTL for multicast frames, default 2, according to the UDA
    -u UUID   Custom UUID instead of auto-generating one
    -v        Show program version
    -w        Disable built-in micro HTTP server on port 1901

Bug report address : https://github.com/troglobit/ssdp-responder/issues
Project homepage   : https://github.com/troglobit/ssdp-responder

The -d URL argument can contain one %s modifier which is replaced with the IP address of the interface the SSDP notification or reply is sent on. For example:

ssdpd -d https://%s:1901/description.xml

See configure --help for some build time options.

Example

The following example assumes the system eth0 interface is connected to an ISP and eth1 to the LAN. Every 300 sec the list of addresses for eth1 are updated, if a new address is added a NOTIFY * message is sent, otherwise NOTIFY * messages are sent every 30 seconds.

ssdpd -i 30 -r 300 eth1

Configure & Build

The GNU Configure & Build system use /usr/local as the default install prefix. In many cases this is useful, but this means the configuration files, cache, and PID files will also use that prefix. Most users have come to expect those files in /etc/ and /var/ and configure has a few useful options that are recommended to use. Hence, you may want to use something like this:

./configure --prefix=/usr --sysconfdir=/etc --runstatedir=/var/run
make -j$(($(nproc) + 1))
sudo make install-strip

Usually your system reserves /usr for native pacakges, so most users drop --prefix, installing to /usr/local, or use --prefix=/opt.

Note: On some systems --runstatedir may not be available in the configure script, try --localstatedir=/var instead.

Building from GIT

The configure script and the Makefile.in files are generated for release tarballs and not stored in GIT. When you work with the GIT source tree you need the GNU automake and autoconf tools:

$ sudo apt install automake autoconf

Now, from the top directory of the cloned GIT tree, call:

$ ./autogen.sh

Static Build

Some people want to build statically, to do this with autoconf add the following LDFLAGS= after the configure script. You may also need to add LIBS=..., which will depend on your particular system:

./configure LDFLAGS="-static" ...

Integration with systemd

For systemd integration libsystemd-dev and pkg-config are required. When the unit file is installed, systemctl can be used to enable and start the daemon:

$ sudo systemctl enable ssdpd.service
$ sudo systemctl start  ssdpd.service

Check that it started properly by inspecting the system log, or:

$ sudo systemctl status ssdpd.service

To stop the service:

$ sudo systemctl stop   ssdpd.service

Origin

Cloned from mrdisc and whacked at with a bat until it replies to SSDP "MSEARCH *" messages used by Windows.