c300x-controller: The API that BTicino never had

Table of Contents

• API
• Handlers
• Setup procedure
• WebRTC
• Homekit
• Development

API

Supports:

• Unlocking door (supporting multiple locks)
• Displaying the unit temp and load
• Rebooting the unit
• Register endpoints to receive doorbell pressed, door locked and door unlocked events
• Enable/disable voice mail and show the status
• Enable/disable the ringer and show the status
• Start dropbear sshd (in case it crashes)
• Validates scrypted setup
• Exposes the voicemail videoclips
• Display the videoclip
• Send MQTT messages for openwebnet events and intercom status
• WebRTC bundle with embedded SIP client and SDP socket server

Handlers

Handlers automatically act on syslog messages being sent on the multicast port 7667. They are handled by multicast-listener.js. At the moment only 1 handler is registered which listens to the openwebnet messages.

Setup procedure

You can choose between an automated install using a script or a manual install.

Automated install

You can execute the install.sh script which will do all manual steps below for you:

bash -c "$(wget -qO - 'https://raw.githubusercontent.com/slyoldfox/c300x-controller/main/install.sh')"

Or if you rather first fetch the script and read it before executing:

wget 'https://raw.githubusercontent.com/slyoldfox/c300x-controller/main/install.sh'
less install.sh
bash install.sh

Manual install

1. Install node.js

mount -oremount,rw /
cd /home/bticino/cfg/extra/
mkdir node
wget https://nodejs.org/download/release/latest-v17.x/node-v17.9.1-linux-armv7l.tar.gz
tar xvfz node-v17.9.1-linux-armv7l.tar.gz --strip-components 1 -C ./node
rm node-v17.9.1-linux-armv7l.tar.gz

2. Install libatomic.so.1

Node will require libatomic.so.1 which isn't shipped with the device, so we need to collect it from another source.

[!IMPORTANT] It's strongly advised to do this step on a different Linux machine, because C300x misses XZ Utils to decompress archives contained in the deb package

cd /tmp
wget http://ftp.de.debian.org/debian/pool/main/g/gcc-10-cross/libatomic1-armhf-cross_10.2.1-6cross1_all.deb
ar x libatomic1-armhf-cross_10.2.1-6cross1_all.deb
tar -xf data.tar.xz
cd usr/arm-linux-gnueabihf/lib/

Now you should find libatomic.so.1.2.0 lib binary. Transfer it to the intercom, to the /lib folder, than create the library symlink

cd /lib
ln -s libatomic.so.1.2.0 libatomic.so.1

3. Check that node.js now works fine

/home/bticino/cfg/extra/node/bin/node -v

should output the version

v17.9.1

4. Install c300x-controller

cd /home/bticino/cfg/extra/
mkdir c300x-controller
wget https://github.com/slyoldfox/c300x-controller/archive/refs/heads/main.tar.gz
tar xvfz main.tar.gz --strip-components 1
rm main.tar.gz

now do a check run

/home/bticino/cfg/extra/node/bin/node /home/bticino/cfg/extra/c300x-controller/controller.js

5. Edit firewall rules

To be able to access the c300x-controller from the network, you have to allow incoming connections through the wireless interface to port 8080. Edit /etc/network/if-pre-up.d/iptables and add the following section at line 38:

# c300x-controller
for i in 8080; do
	iptables -A INPUT -p tcp -m tcp --dport $i -j ACCEPT
	iptables -A INPUT -p tcp -m tcp --sport $i -j ACCEPT
done

then apply changes

/etc/init.d/networking restart

and check that the controller is now reachable at http://<your_device_ip>:8080

[!WARNING] If you prefer, at your own risk, you can entirely disable iptables firewall

$ mv /etc/network/if-pre-up.d/iptables /home/bticino/cfg/extra/iptables.bak
$ mv /etc/network/if-pre-up.d/iptables6 /home/bticino/cfg/extra/iptables6.bak

6. Running it at startup

Create a new init.d script under /etc/init.d/c300x-controller with the following content

#! /bin/sh

### BEGIN INIT INFO
# Provides:         c300x-controller
# Default-Start:    2 3 4 5
# Default-Stop:     0 1 6
# Short-Description:    c300x-controller
### END INIT INFO

set -e

PIDFILE=/var/run/c300x-controller
DAEMON="/home/bticino/cfg/extra/node/bin/node"
DAEMON_ARGS="/home/bticino/cfg/extra/c300x-controller/controller.js"

. /etc/init.d/functions

case "$1" in
    start)
        echo "Starting c300x-controller"
		if start-stop-daemon --start --quiet --oknodo --background  --make-pidfile --pidfile ${PIDFILE} --exec ${DAEMON} -- ${DAEMON_ARGS} ; then
			exit 0
		fi
        ;;

    stop)
        echo "Stopping c300x-controller"
        if start-stop-daemon --stop --quiet --oknodo --pidfile ${PIDFILE} --retry=TERM/3/KILL/2; then
            rm -f ${PIDFILE}
            exit 0
        fi
        ;;

    restart)
        echo "Restarting c300x-controller"
        if start-stop-daemon --stop --quiet --oknodo --retry 30 --pidfile ${PIDFILE}; then
            rm -f ${PIDFILE}
        fi
	usleep 150000 
        if start-stop-daemon --start --quiet --oknodo --background --make-pidfile --pidfile ${PIDFILE} --retry=TERM/3/KILL/2 --exec ${DAEMON} -- ${DAEMON_ARGS} ; then
            exit 0
        fi
        ;;

    status)
        #status ${DAEMON} && exit 0 || exit $?
        pid=`ps -fC node | grep "$DAEMON $DAEMON_ARGS" | awk '{print $2}'`
        if [ "$pid" != "" ]; then
                echo "$DAEMON $DAEMON_ARGS (pid $pid) is running..."
        else
                echo "$DAEMON $DAEMON_ARGS stopped"
        fi
        ;;

    *)
        echo "Usage: $0 {start|stop|restart|status}"
        exit 1
esac

exit 0

make it executable

chmod 755 /etc/init.d/c300x-controller

then create the symlink for init.d runlevel 5

cd /etc/rc5.d/
ln -s ../init.d/c300x-controller S40c300x-controller

7. Final steps

Make the filesystem read-only again

mount -oremount,ro /

than reboot the unit and verify that everything is working as expected.

WebRTC

Since version 2024.5.1 - you can choose between bundle.js, bundle-webrtc.js or bundle-homekit.js.

To use WebRTC, use the bundle-webrtc.js file instead of the bundle.js.

In config.json add the following config:

    "sip" : {
        "from": "[email protected]",
        "to": "[email protected]",
        "domain": "XXXXXXX.bs.iotleg.com",
        "debug": false
    }

Add the webrtc to the linphone files if you wish to receive incoming calls.

When starting the WebRTC bundle, an additional SDP server will be available at tcp://192.168.0.X:8081.

This allows you to use ffplay -f sdp -i tcp://192.168.0.XX:8081 or ffmpeg -f sdp -i tcp://192.168.XX:8081 to setup the underlying SIP call and view the camera.

You can use the Home Assistant add-on or integration at https://github.com/AlexxIT/WebRTC to add a WebRTC card to your dashboard.

The Home Assistant add-on or integration has the ability to run https://github.com/AlexxIT/go2rtc as an embedded process on your HA instance (or as a standalone process).

You can add a stream to the Bticino intercom by specifying the following go2rtc.yaml

streams:
  doorbell:
    - "ffmpeg:tcp://192.168.0.XX:8081#video=copy#audio=pcma"    
    - "exec:ffmpeg -re -fflags nobuffer -f alaw -ar 8000 -i - -ar 8000 -acodec speex -f rtp -payload_type 97 rtp://192.168.0.XX:40004#backchannel=1"

The ffmpeg:tcp://192.168.0.XX:8081#video=copy#audio=pcma" line talks to the SDP server inside the c300-controller and will setup a SIP call in the background.

The options #video=copy#audio=pcma tell go2rtc to copy the h264 and transcode the audio (from speex) to pcma

The exec:ffmpeg ... line specifies the backchannel. This is the stream from your (browser) microphone towards the intercom. It will read the microphone data from the websocket and transcode it to speex and send it the intercom using rtp. The port 40004 is the port of the UDP proxy inside the c300-controller.

The WebRTC card configuration looks like this:

type: custom:webrtc-camera
url: doorbell
mode: webrtc
media: video,audio,microphone

To use the microphone you must make sure that your Home Assistant instance is running on https://. The microphone does not activate on http://, this is a browser security measure.

If you managed to get this working on your local network, you will still need to fix something to make sure you can reach the stream from the internet.

Have a look at https://github.com/AlexxIT/go2rtc?tab=readme-ov-file#module-webrtc for this.

In my case I forwarded port 8555 to my internal go2rtc instance and specified my IP in the candidates section in go2rtc.yaml

webrtc:
  candidates:
    - 216.58.210.174:8555  # if you have static public IP-address

BONUS:

If you don't wish to run the go2rtc embedded process in HA, you can run it natively on your intercom:

Fetch the binaries for go2rtc and ffmpeg: https://github.com/AlexxIT/go2rtc/releases/latest/download/go2rtc_linux_arm https://johnvansickle.com/ffmpeg/ (armhf version)

Adjust the paths to where your ffmpeg binary is and adjust your port forwards.

ffmpeg:
  bin: /home/bticino/cfg/extra/ffmpeg-linux-arm  # path to ffmpeg binary

Replace the IP above with 127.0.0.1 and all transcoding and handling is now on your intercom.

Inside HA add the Webrtc with http://192.168.0.XX:1984 (replace with the IP of your intercom).

Homekit

Since version 2024.5.1 - you can choose between bundle.js, bundle-webrtc.js or bundle-homekit.js.

WARNING: Homekit support is experimental, work in progress and highly untested.

To use Homekit, use the bundle-homekit.js file instead of the bundle.js. This will expose a Homekit bridge.

The PIN code to pair is shown in the console or in the file config-homekit.json after startup.

At the moment the Bridge exposes:

• All locks
• Mute/unmute switch
• Voicemail switch (C300X only)

Development

For development, open an ssh connection to you intercom and forward the openwebnet port.

ssh -L127.0.0.1:20000:127.0.0.1:20000 [email protected]

If you want to receive openwebnet messages you will need to login to the intercom and forward the syslog packets

You can do this with socat, an arm build is avaialable for download here: https://github.com/therealsaumil/static-arm-bins/blob/master/socat-armel-static

ssh -L127.0.0.1:20000:127.0.0.1:20000 [email protected] /home/bticino/cfg/extra/socat-armel-static UDP4-RECVFROM:7667,reuseaddr,fork UDP4-SENDTO:192.168.0.5:7667

Start the controller with

node controller.js

You can create a (production) webpack bundle by executing:

npm run build

You can then run the (production) webpack bundle by executing:

npm start

[!WARNING] Note that some APIs might not work locally (e.g. reboot api, load) - because they use native commands on the intercom.