Chrome Native Messaging Host for KeePassXC (aka keepassxc-proxy)

Self-contained app intented to act as proxy between Google Chrome browser and KeePassXC app.

Rationale: https://github.com/varjolintu/keepassxc-browser/issues/1#issuecomment-310135201

Create app binary

Binaries can be created for multiple runtimes/platforms supported by dotnet core.

Supported runtimes:

• centos.7-x64;
• debian.8-x64
• ol.7.0-x64
• ol.7.1-x64
• ol.7.2-x64
• opensuse.13.2-x64
• osx.10.10-x64
• osx.10.11-x64
• linuxmint.17-x64
• linuxmint.17.1-x64
• linuxmint.17.2-x64
• linuxmint.17.3-x64
• rhel.7.2-x64
• ubuntu.14.04-x64
• ubuntu.14.10-x64
• ubuntu.15.04-x64
• ubuntu.15.10-x64
• ubuntu.16.04-x64
• win7-x64
• win7-x86]

All possible runtimes can be found in chrome_native_messaging_host.csproj.

Run docker container for building app:

docker run -it -v $(pwd):/native_messaging_host microsoft/dotnet

From running container:

cd /native_messaging_host

Build binary with selected runtime ubuntu.16.04-x64:

dotnet restore
dotnet build
dotnet publish -c Release -o out -r ubuntu.16.04-x64

Binary can now be accesible from docker host:

./out/chrome_native_messaging_host

All dotnet runtime libraries included. *More info: https://github.com/dotnet/dotnet-docker-samples/tree/master/dotnetapp-selfcontained

Register Google Chrome native messaging host

Following snippet will register native messaging host. Adjust accordingly.

CHROME_NATIVE_HOSTS_PATH="${HOME}/.config/google-chrome/NativeMessagingHosts"

mkdir -p $CHROME_NATIVE_HOSTS_PATH

PROXY_PATH="$(pwd)/out/chrome_native_messaging_host"
cat << EOF > "${CHROME_NATIVE_HOSTS_PATH}/com.varjolintu.keepassxc_browser.json" && echo DONE
{
  "name": "com.varjolintu.keepassxc_browser",
  "description": "KeepassXC integration with Chrome with Native Messaging support",
  "path" : "${PROXY_PATH}",
  "type": "stdio",
  "allowed_origins": [
    "chrome-extension://iopaggbpplllidnfmcghoonnokmjoicf/",
    "chrome-extension://fhakpkpdnjecjfceboihdjpfmgajebii/"
  ]
}
EOF

Debug

• Start Chrome in Terminal. All logging is done to stderr.
• Monitor traffic with tcpdump

tcpdump -i lo 'port 19700' -vv -A