# signal-cli

signal-cli is a commandline interface
for [libsignal-service-java](https://github.com/WhisperSystems/libsignal-service-java). It supports registering,
verifying, sending and receiving messages. To be able to link to an existing Signal-Android/signal-cli instance,
signal-cli uses a [patched libsignal-service-java](https://github.com/AsamK/libsignal-service-java), because
libsignal-service-java does not yet
support [provisioning as a linked device](https://github.com/WhisperSystems/libsignal-service-java/pull/21). For
registering you need a phone number where you can receive SMS or incoming calls.

signal-cli is primarily intended to be used on servers to notify admins of important events. For this use-case, it has a daemon mode with D-BUS
interface ([man page](https://github.com/AsamK/signal-cli/blob/master/man/signal-cli-dbus.5.adoc)) and JSON-RPC interface ([documentation](https://github.com/AsamK/signal-cli/wiki/JSON-RPC-service)). For the JSON-RPC interface there's also a simple [example client](https://github.com/AsamK/signal-cli/tree/master/client), written in Rust.

## Installation

You can [build signal-cli](#building) yourself or use
the [provided binary files](https://github.com/AsamK/signal-cli/releases/latest), which should work on Linux, macOS and
Windows. There's also a [docker image and some Linux packages](https://github.com/AsamK/signal-cli/wiki/Binary-distributions) provided by the community.

System requirements:

- at least Java Runtime Environment (JRE) 17
- native library: libsignal-client

  The native libs are bundled for x86_64 Linux (with recent enough glibc), Windows and MacOS. For other
  systems/architectures
  see: [Provide native lib for libsignal](https://github.com/AsamK/signal-cli/wiki/Provide-native-lib-for-libsignal)

### Install system-wide on Linux

See [latest version](https://github.com/AsamK/signal-cli/releases).

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

You can find further instructions on the Wiki:

- [Quickstart](https://github.com/AsamK/signal-cli/wiki/Quickstart)
- [DBus Service](https://github.com/AsamK/signal-cli/wiki/DBus-service)

## Usage

For a complete usage overview please read
the [man page](https://github.com/AsamK/signal-cli/blob/master/man/signal-cli.1.adoc) and
the [wiki](https://github.com/AsamK/signal-cli/wiki).

Important: The ACCOUNT is your phone number in international format and must include the country calling code. Hence it
should start with a "+" sign. (See [Wikipedia](https://en.wikipedia.org/wiki/List_of_country_calling_codes) for a list
of all country codes.)

* Register a number (with SMS verification)

        signal-cli -a ACCOUNT register

  You can register Signal using a land line number. In this case you can skip SMS verification process and jump directly
  to the voice call verification by adding the `--voice` switch at the end of above register command.

  Registering may require solving a CAPTCHA
  challenge: [Registration with captcha](https://github.com/AsamK/signal-cli/wiki/Registration-with-captcha)

* Verify the number using the code received via SMS or voice, optionally add `--pin PIN_CODE` if you've added a pin code
  to your account

        signal-cli -a ACCOUNT verify CODE

* Send a message

        signal-cli -a ACCOUNT send -m "This is a message" RECIPIENT

* Pipe the message content from another process.

        uname -a | signal-cli -a ACCOUNT send --message-from-stdin RECIPIENT

* Receive messages

        signal-cli -a ACCOUNT receive

**Hint**: The Signal protocol expects that incoming messages are regularly received (using `daemon` or `receive`
command). This is required for the encryption to work efficiently and for getting updates to groups, expiration timer
and other features.

## Storage

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

        $XDG_DATA_HOME/signal-cli/data/
        $HOME/.local/share/signal-cli/data/

## Building

This project uses [Gradle](http://gradle.org) for building and maintaining dependencies. If you have a recent gradle
version installed, you can replace `./gradlew` with `gradle` in the following steps. Alternatively, you can install the prerequisites with:
```
yes | sudo apt-get install default-jre
yes | sudo apt-get install openjdk-17-jdk
export JAVA_HOME=/usr/lib/jvm/java-1.17.0-openjdk-amd64
```

1. Checkout the source somewhere on your filesystem with and open the repository:

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

2. Execute Gradle:

        ./gradlew build

   2a. Create shell wrapper in *build/install/signal-cli/bin*:

        ./gradlew installDist

   2b. Create tar file in *build/distributions*:

        ./gradlew distTar

   2c. Create a fat tar file in *build/libs/signal-cli-fat*:

        ./gradlew fatJar

   2d. Compile and run signal-cli:

        ./gradlew run --args="--help"
3. Now you can copy the distribution that you just build, with:
```   
        cd build/distributions
        # Unpack the compressed .tar file to the /opt directory.
        sudo tar xf signal-cli-0.*.*.tar -C /opt
        # Move the unpacked distribution into the /usr/local/bin/ directory
        sudo ln -sf /opt/signal-cli-0.*.*/bin/signal-cli /usr/local/bin/
```  
4. You can verify `signal-cli` works, by typing: `signal-cli -v` which should return something like: `signal-cli 0.x.y`.
5. Now you can choose to keep your phone registered and add this device using [these instructions](https://github.com/AsamK/signal-cli/wiki/Linking-other-devices-%28Provisioning%29). Or you can unregisters Signal on your phone, if you used Signal on your phone, and use this device as your main Signal device. The latter can be done either using the usage instructions above (`signal-cli -a ACCOUNT register` etc.), or, if you are prompted to fill in a captcha, using [these instructions](https://github.com/AsamK/signal-cli/wiki/Registration-with-captcha).

### Building a native binary with GraalVM (EXPERIMENTAL)

It is possible to build a native binary with [GraalVM](https://www.graalvm.org). This is still experimental and will not
work in all situations.

1. [Install GraalVM and setup the enviroment](https://www.graalvm.org/docs/getting-started/#install-graalvm)
2. [Install prerequisites](https://www.graalvm.org/reference-manual/native-image/#prerequisites)
3. Execute Gradle:

        ./gradlew nativeCompile

   The binary is available at *build/native/nativeCompile/signal-cli*

## FAQ and Troubleshooting

For frequently asked questions and issues have a look at the [wiki](https://github.com/AsamK/signal-cli/wiki/FAQ)

## 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