4.9 KiB
sys-git
Git operations through Qrexec in Qubes OS.
Table of Contents
Description
Setup a Git server called "sys-git", an offline Git Server that can be accessed from client qubes via Qrexec. Access control via Qrexec policy can restrict access to certain repositories, set of git actions for Fetch, Push and Init. This is an implementation of split-git.
Alternatives comparison
The following alternatives will be compared against each other and this implementation:
- Rudd-O/git-remote-qubes
- QubesOS-contrib/qubes-app-split-git
- qubes-os.org/doc/development-workflow/#git-connection-between-vms
| sys-git | git-remote-qubes | qubes-app-split-git | git-connection-between-vms | |
|---|---|---|---|---|
| Codebase Size | Small | Large | Large | Small |
| Custom Protocol | True | True | True | False |
| Path | Repository | Absolute | Repository | Repository |
| Repository restriction | True | False | True | True |
| No hanging | True | True | True | False |
| Fetch | True | True | True (only tags) | True |
| Push | True | True | False | True |
| Init | True | False | False | False |
| Validates Git communication | False | False | True | False |
| Verifies tag signature | False | False | True | False |
Installation
- Top
qubesctl top.enable sys-git
qubesctl --targets=tpl-sys-git,sys-git state.apply
qubesctl top.disable sys-git
- State
qubesctl state.apply sys-git.create
qubesctl --skip-dom0 --targets=tpl-sys-git state.apply sys-git.install
qubesctl --skip-dom0 --targets=sys-git state.apply sys-git.configure
Installation on the client template:
qubesctl --skip-dom0 --targets=tpl-dev state.apply sys-git.install-client
Access control
Default policy: any qube can ask via the @default target if you allow
it to Fetch from, Push to and Init on sys-git.
Recommended usage:
- Init: Argument useful when allowing a qube to always create a repository on the server.
- Fetch: Fetch can be allowed by less trusted qubes.
- Push: Push should only be made by trusted qubes.
Allow qube dev to Fetch from sys-git, but ask to Push and Init:
qusal.GitFetch * dev @default allow target=sys-git
qusal.GitPush * dev @default ask target=sys-git default_target=sys-git
qusal.GitInit * dev @default ask target=sys-git default_target=sys-git
qusal.GitFetch * dev @anyvm deny
qusal.GitPush * dev @anyvm deny
qusal.GitInit * dev @anyvm deny
Allow qube untrusted to Fetch repo if using target name sys-git but
deny Push and Init to any other qube:
qusal.GitFetch +repo untrusted sys-git ask target=sys-git default_target=sys-git
qusal.GitFetch * untrusted @anyvm deny
qusal.GitPush * untrusted @anyvm deny
qusal.GitInit * untrusted @anyvm deny
Deny Fetch, Push and Init from any qube to any other qube:
qusal.GitFetch * @anyvm @anyvm deny
qusal.GitPush * @anyvm @anyvm deny
qusal.GitInit * @anyvm @anyvm deny
Usage
Initialize the server repository
There are a few constraints regarding repositories:
- Must be created under
/home/user/srcinsys-git; - Names must have only letters, numbers, hyphen, underscore and dot. Must not begin or end with dot, hyphen and underscore.
In sys-git, create bare repositories under /home/user/src.
From the server:
git init --bare ~/src/X.git
You must use the .git prefix to indicate a bare repository.
Or from the client, if the qusal.GitInit policy allows:
cd ~/path/to/repo
git init-qrexec
Prepare the client
Qrexec protocol is supported with the following URL format:
qrexec://<QUBE>/<REPO>, where the <QUBE> field can be a literal name or
token and the <REPO> field is the name of the repository that exists on
sys-git under /home/user/src.
Clone an existing repository:
git clone qrexec://@default/qubes-doc
Or Initialize a new repository:
git init qubes-doc
cd qubes-doc
Add a remote using the Qrexec protocol:
git remote add sg qrexec://@default/qubes-doc
Test fetching from the newly added remote:
git fetch sg
Make changes to the git repository as you normally would on any system.
Push to the server and set it as the default upstream:
git push -u sg main
Following pushes will be simpler:
git push