Signal-cli: command-line and dbus interface to Signal

signal-cli is a commandline interface for libsignal-service-java. It supports registering, verifying, sending and receiving messages. To be able to receive messages signal-cli uses a patched libsignal-service-java, because libsignal-service-java does not yet support registering for the websocket support nor provisioning as a slave device. For registering you need a phone number where you can receive SMS or incoming calls. It is primarily intended to be used on servers to notify admins of important events. For this use-case, it has a dbus interface, that can be used to send messages from any programming language that has dbus bindings.

Installation

You can build signal-cli yourself, or use the provided binary files, which should work on Linux, macOS and Windows. For Arch Linux there is also a package in AUR. You need to have at least JRE 7 installed, to run signal-cli.

Install system-wide on Linux

See latest version.

export VERSION=<latest version, format "x.y.z">
wget https://github.com/AsamK/signal-cli/releases/download/v"${VERSION}"/signal-cli-"${VERSION}".tar.gz
sudo tar xf signal-cli-"${VERSION}".tar.gz -C /opt
sudo ln -sf /opt/signal-cli-"${VERSION}"/bin/signal-cli /usr/local/bin/

Usage

usage: signal-cli [-h] [-v] [--config CONFIG] [-u USERNAME | --dbus | --dbus-system] {link,addDevice,listDevices,removeDevice,register,verify,send,quitGroup,updateGroup,listIdentities,trust,receive,daemon} ...

See also: man page in asciidoc format

The USERNAME (your phone number) must include the country calling code, i.e. the number must start with a "+" sign. (See Wikipedia for a list of all country codes.

• Register a number (with SMS verification)

  signal-cli -u USERNAME register

• Register a number (with voice verification)

  signal-cli -u USERNAME register -v

• Verify the number using the code received via SMS or voice

  signal-cli -u USERNAME verify CODE

• Send a message to one or more recipients

  signal-cli -u USERNAME send -m "This is a message" [RECIPIENT [RECIPIENT ...]] [-a [ATTACHMENT [ATTACHMENT ...]]]

• Pipe the message content from another process.

  uname -a | signal-cli -u USERNAME send [RECIPIENT [RECIPIENT ...]]

• Receive messages

  signal-cli -u USERNAME receive

• Groups

  • Create a group

    signal-cli -u USERNAME updateGroup -n "Group name" -m [MEMBER [MEMBER ...]]

  • Update a group

    signal-cli -u USERNAME updateGroup -g GROUP_ID -n "New group name" -a "AVATAR_IMAGE_FILE"

  • Add member to a group

    signal-cli -u USERNAME updateGroup -g GROUP_ID -m "NEW_MEMBER"

  • Leave a group

    signal-cli -u USERNAME quitGroup -g GROUP_ID

  • Send a message to a group

    signal-cli -u USERNAME send -m "This is a message" -g GROUP_ID

• Linking other devices (Provisioning)

  • Connect to another device

    signal-cli link -n "optional device name"

    This shows a "tsdevice:/…" link, if you want to connect to another signal-cli instance, you can just use this link. If you want to link to and Android device, create a QR code with the link (e.g. with qrencode) and scan that in the Signal Android app.

  • Add another device

    signal-cli -u USERNAME addDevice --uri "tsdevice:/…"
    

    The "tsdevice:/…" link is the one shown by the new signal-cli instance or contained in the QR code shown in Signal-Desktop or similar apps. Only the master device (that was registered directly, not linked) can add new devices.

  • Manage linked devices

    signal-cli -u USERNAME listDevices
    
    signal-cli -u USERNAME removeDevice -d DEVICE_ID
    

• Manage trusted keys

  • View all known keys

    signal-cli -u USERNAME listIdentities

  • View known keys of one number

    signal-cli -u USERNAME listIdentities -n NUMBER

  • Trust new key, after having verified it

    signal-cli -u USERNAME trust -v FINGER_PRINT NUMBER

  • Trust new key, without having verified it. Only use this if you don't care about security

    signal-cli -u USERNAME trust -a NUMBER

• Set configuration directory

    signal-cli --config=/home/other_user/.config/signal

  This is particularily useful in the case, when you would like to run the signal-cli tool as a different user as the one, that was used to register the account. You should make sure, that the caller has full read/write access to the given directory.

DBus service

signal-cli can run in daemon mode and provides an experimental dbus interface. For dbus support you need jni/unix-java.so installed on your system (Debian: libunixsocket-java ArchLinux: libmatthew-unix-java (AUR)).

• Run in daemon mode (dbus session bus)

    signal-cli -u USERNAME daemon

• Send a message via dbus

    signal-cli --dbus send -m "Message" [RECIPIENT [RECIPIENT ...]] [-a [ATTACHMENT [ATTACHMENT ...]]]

System bus

To run on the system bus you need to take some additional steps. It’s advisable to run signal-cli as a separate unix user, the following steps assume you created a user named signal-cli. These steps, executed as root, should work on all distributions using systemd.

Mind the fact that signal.service executes the signal-cli with "--config /var/lib/signal-cli". If you registered with user signal-cli, remove the config option.

cp data/org.asamk.Signal.conf /etc/dbus-1/system.d/
cp data/org.asamk.Signal.service /usr/share/dbus-1/system-services/
cp data/signal.service /etc/systemd/system/
sed -i -e "s|%dir%|<INSERT_INSTALL_PATH>|" -e "s|%number%|<INSERT_YOUR_NUMBER>|" /etc/systemd/system/signal.service
systemctl daemon-reload
systemctl enable signal.service
systemctl reload dbus.service

Make sure to use "--dbus-system" with the send command, the service will be autostarted by dbus the first time it is requested.

Storage

The password and cryptographic keys are created when registering and stored in the current users home directory:

    $HOME/.config/signal/data/

For legacy users, the old config directory is used as a fallback:

    $HOME/.config/textsecure/data/

Building

This project uses Gradle for building and maintaining dependencies. If you have a recent gradle version installed, you can replace ./gradlew with gradle in the following steps.

1. Checkout the source somewhere on your filesystem with

   git clone https://github.com/AsamK/signal-cli.git

2. Execute Gradle:

   ./gradlew build

3. Create shell wrapper in build/install/signal-cli/bin:

   ./gradlew installDist

4. Create tar file in build/distributions:

   ./gradlew distTar

Troubleshooting

If you use a version of the Oracle JRE and get an InvalidKeyException you need to enable unlimited strength crypto. See https://stackoverflow.com/questions/6481627/java-security-illegal-key-size-or-default-parameters for instructions.

License

This project uses libsignal-service-java from Open Whisper Systems:

https://github.com/WhisperSystems/libsignal-service-java

Licensed under the GPLv3: http://www.gnu.org/licenses/gpl-3.0.html