Wire - Audio, Video, and Signaling (AVS)

This repository is part of the source code of Wire. You can find more information at wire.com or by contacting [email protected].

You can find the published source code at github.com/wireapp.

For licensing information, see the attached LICENSE file and the list of third-party licenses at wire.com/legal/licenses/.

Build Requirements

Apart from the basic toolchain for each system, you need these:

• clang, libc++
• yasm (for video only)
• alsa (for Linux only).

For OSX and iOS, you should have Xcode and the Command Line Tools for your specific version of both OSX and Xcode. Things will break if you have the wrong version. You can install the latter via menu Xcode, then Open Developer Tool, then More Developer Tools.

For getting autoconf, automake, libtool, and yasm, we suggest Homebrew. Follow the instructions there, then:

$ brew install \
  autoconf \
  automake \
  libsodium \
  libtool \
  multirust \
  pkg-config \
  protobuf-c \
  readline \
  sdl \
  yasm
$ multirust default nightly

For Android, you need both the Android SDK as well as the Android NDK. Just get the latest versions and install them somewhere cozy. You need to export two environment variables ANDROID_SDK_ROOT and ANDROID_NDK_ROOT pointing to the respective location. Unless you do a one-off, you probably want to add them to your .bash_profile.

For Linux, you need to install the packages for the stuff mentioned above or, of course, build it all from scratch. If you are on a Debian-esque system, do this:

$ sudo apt-get install \
  autoconf \
  automake \
  clang \
  libasound2-dev \
  libc++-dev \
  libc++abi-dev \
  libevent-dev \
  libprotobuf-c-dev \
  libreadline-dev \
  libsodium-dev \
  libtool \
  libx11-dev \
  libxcomposite-dev \
  libxdamage-dev \
  libxrender-dev \
  make \
  pkgconf \
  protobuf-c-compiler \
  yasm \
  zlib1g-dev \
  zip

$ curl -sSf https://static.rust-lang.org/rustup.sh | sh -s -- --channel=nightly

For Windows, you will have to start by adding your system to the build system. Good luck!

Build Instructions

AVS will work with Google WebRTC which first needs to be pulled from Google and pre-compiled. To do that go to the webrtc directory and run:

./scripts/build.sh ./scripts/package.sh

This should be done on OSX for headers and iOS+OSX libs and on Linux for Linux+Android libs. The scripts pull from Googles repos, apply a patch for Android (in patches dir), build and package the libs into zips, which get copied to contrib/webrtc. Expected zips are:

contrib/webrtc/webrtc_72.local_android.zip contrib/webrtc/webrtc_72.local_headers.zip contrib/webrtc/webrtc_72.local_ios.zip contrib/webrtc/webrtc_72.local_linux.zip contrib/webrtc/webrtc_72.local_osx.zip

All zips are needed to build AVS, but can be empty files if not needed: e.g. you can run touch contrib/webrtc/webrtc_72.local_android.zip if you dont intend to build for Android.

AVS has more dependencies that need to be updated with:

./prepare.sh

Next step is to build AVS itself. When building AVS with local webrtc, invoke make with:

make WEBRTC_VER .local

For example:

make WEBRTC_VER=72.local

The deliverables are being built by saying make WEBRTC_VER <release>.local dist. You can limit this to only select target platforms through make WEBRTC_VER <release>.local dist_android, make WEBRTC_VER <release>.local dist_osx and make WEBRTC_VER <release>.local dist_ios. All of them take quite a while on a fresh checkout.

You'll find the deliverables in build/dist/{android,ios,osx}.

You can also build just the wrappers for a given architecture by saying make wrappers AVS_OS=<os> AVS_ARCH=<arch> where <os> is one of android, ios, or osx. There is no wrappers for Linux, so you are out of luck there. For <arch> there are several possible values depending on the OS. You can just leave the whole thing out and will receive reasonable defaults (ARMv7 or X86-64). Have a look at mk/target.mk for more on this.

If you want to have a local version of a dist_* target that hasn't all the necessary architectures but builds quicker, you can pass DIST_ARCH=<your_arch> to make and will only built for that architecture:

$ make WEBRTC_VER=72.local dist_ios DIST_ARCH=armv7

will build an iOS distribution that will only contain armv7 instead of the usual five architectures.

Using the Library

During the build, a set of static libraries is being built. You can use this library in your own projects.

You'll find the APIs in include/*.h. avs.h is your catchall include file. Always use that to protect yourself agains reorganizations.

Linking is a bit tricky, we'll add instructions soon. The easiest is probably to add build/$(your-platform)/lib to your library path and then add all .a files in there as -l arguments.

Tools

A tool for testing basic functionality called zcall can be built with e.g.

make WEBRTC_VER=72.local zcall

Use zcall -help to see available options. To log into the client:

./zcall -e <Wire-login-email> -p <password>

Next step is to register a client:

:reg_client

Please note that only 7 clients can be registered and it may become necessary to delete a client before a new one can be registered.

Architecture overview:

                      .----------.  .------.
                      |  Engine  |  | Mill |
                      '----------'  '------'
                     /      |
    .--------------.        |
    |   EGCALL     |  .----------.  .-----------.  .----------.
    |   ECALL      |  | REST     |  | Media-mgr |  | Netprobe |
    |   ECONN      |  | Nevent   |  '-----------'  '----------'
    '--------------'  '----------'
       |      |
  .---------. |  .-----.
  |Mediaflow| |  | DCE |
  '---------'\|  '-----'
       |      |\                                   .----------.
   .-------.  | \.--------.                        | Protobuf |
   |aucodec|  |  |vidcodec|                        '----------'
   '-------'  |  '--------'
       |     / \     |                             .----------.
   .-------./   \.--------.                        | Conf-Pos |
   |  VOE  |     |  VIE   |                        '----------'
   '-------'     '--------'



    .------------------------------.
    | Low-level utility modules:   |
    | - audummy (Dummy audio-mod)  |
    | - base (Base module)         |
    | - cert (Certificates)        |
    | - dict (Dictionary)          |
    | - jzon (Json wrappers)       |
    | - log (Logging framework)    |
    | - queue (Packet queue)       |
    | - sem (Semaphores)           |
    | - store (Persistent Storage) |
    | - trace (Tracing tool)       |
    | - uuid (UUID helpers)        |
    | - zapi (ZETA-protocol API)   |
    | - ztime (Timestamp helpers)  |
    '------------------------------'

Some specifications implemented:

• https://tools.ietf.org/html/draft-ietf-mmusic-trickle-ice-01
• https://tools.ietf.org/html/draft-ietf-rtcweb-stun-consent-freshness-11
• https://tools.ietf.org/html/rfc7845
• https://tools.ietf.org/html/draft-ietf-rtcweb-data-channel-13

Reporting bugs

When reporting bugs against AVS please include the following:

• Wireshark PCAP trace (download Wireshark)
• Full logs from client
• Session-ID
• Which Backend was used
• Exact version of client
• Exact time when call was started/stopped
• Name/OS of device
• Adb logcat for Android