Gitmouth - SSH-to-Git Server for Openruko
gitmouth is a small SSH server written in Python using the Twisted
engine framework to handle git push and pull
commands users make to manage their remote git repositories. It authenticates
the user by matching their public key fingerprint against the API server
database, then asks the API server to provision a dyno (a virtualization
container) with the respective git repository mounted, finally it connects to
this dyno over an SSH-like protocol and runs the git-receive-pack or git-
upload-pack command, which in turn will execute the buildpack via git hooks.
For those not familiar with Heroku infrastructure, as buildpacks can contain potentially dangerous code the git command has to run inside an isolated dyno too, hence gitmouth is simply a bridge from the ssh transport to where the git commands run inside a dyno, authenticating and authorizing the request in the pipeline.
Tested on Linux 3.2 using Python 2.7.3.
On a fresh Ubuntu 12.04 LTS instance:
$ apt-get install python python-dev $ apt-get install python-virtualenv
Please share experiences with CentOS, Fedora, OS X, FreeBSD etc... I am fairly confident it will not work on Windows based machines however.
Ensure virtualenv is installed then:
# Getting the code $ git clone https://github.com/openruko/gitmouth.git gitmouth $ cd gitmouth # Isolating and installing dependencies $ make init # Setting up temporary openssl certs $ make certs
gitmouth will check for the presence of several environment variables, these
must be configured as part of the process start - e.g. configured in
supervisord or as part of boot script see
- APISERVER_KEY - special key to authenticate with API server. Example:
$ cat > .env << EOF PYTHONUNBUFFERED=true # to avoid buffering logs APISERVER_KEY=$WHAT_WAS_WRITTEN_AT_THE_END_OF_APISERVER_SETUP EOF $ foreman start
Help and Todo
My Python is a little rusty especially in the areas of pythonic practices, feel free to contribute improvements and share thoughts.
Pass SIGTERM, SIGKILL through to dyno
Flow control using SIGCONT/SIGSTOP
Max timeout Kill the event chain after X minutes
Brute force attacks - Limit connections by user/IP
Locking - only one concurrent commit per repository
gitmouth and other
openruko components are licensed under MIT.