Contributing to OpenConnect

Contributions to OpenConnect are very welcome. You don't need to be able to write code. Testing, documentation improvements and especially translations are all extremely useful. Some specific suggestions and requests for help can be found below.

Submitting Patches

Patches can be sent to the mailing list or directly to the author in private email. We are also experimenting with using GitLab, so please feel free to file issues and submit merge requests at https://gitlab.com/openconnect/openconnect.

When submitting patches to be included in OpenConnect, please certify that your patch meets the criteria below by including include a sign-off line in your email which looks like this:

This confirms that you are permitted to submit the patch for inclusion in OpenConnect under the LGPLv2.1 licence. The full text of the certificate is as follows:

• Developer's Certificate of Origin 1.1

  By making a contribution to this project, I certify that:

  1. The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; or
  2. The contribution is based upon previous work that, to the best of my knowledge, is covered under an appropriate open source license and I have the right under that license to submit that work with modifications, whether created in whole or in part by me, under the same open source license (unless I am permitted to submit under a different license), as indicated in the file; or
  3. The contribution was provided directly to me by some other person who certified (1), (2) or (3) and I have not modified it.

  and also that:

  • I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved.

What needs doing?

Translations for OpenConnect are maintained in the GNOME NetworkManager-openconnect module. Translations can be contributed by joining the GNOME team as described on their TranslationProject wiki page, or simply by editing one of the language files in the po/ directory and sending the resulting patch (or file) to the mailing list.

If there are questions about the messages because the intent is not clear, or if the messages could be improved to make translation easier or better, please also feel free to ask or make suggestions on the mailing list.

Documentation / Web Site

OpenConnect is designed with the principle that "if it needs documenting, fix it instead". That isn't to say that we don't have documentation. But if a user finds something non-obvious and has to look it up in the documentation, then that in itself is a little bit of a usability failure. Software should Just Work™.

So if you find something that is more complex than it needs to be, and you think it should Just Work™ then please don't hesistate to tell us bout it.

Any improvements to the documentation are most welcome. In particular:

• Update web site to be mobile-friendly
  The current template is definitely showing its age, and could very much do with an overhaul.

Testing

All testing is valuable, and please do let us know if anything doesn't work when you think it should. There are some things which the regular developers don't have easy access to test, some help with testing these would be particularly welcome:

• Testing a PAN GlobalProtect VPN with IPv6 internal addresses.
  We think we know how this works, but we've not been able to test.
• Various authentication methods for Pulse Secure.
  Although it looked sane at first, the Pulse protocol has a lot of horrid special cases. Aside from the Host Checker most should be working, but please test and let us know if anything is missing or wrong.

New Protocols

There are some other protocols which would be good to add to OpenConnect. Getting a new protocol to the point where it basically works to send and receive traffic is only a few hours of work, and can be very rewarding.

For some protocols we already know how they work on the wire and it's mostly just a matter of typing. For others we might have to observe the existing clients to learn how they work.

These would be great projects for someone to take on as a learning exercise, or perhaps even Google Summer of Code projects.

• CheckPoint VPN
  This is an IPSec-based VPN with fallback to using the SSL transport. Some discussion of OpenConnect support in this GitLab ticket.
• Cisco / Nortel IPSec VPN
  These IPSec-based protocols are already supported by vpnc to differing extents, but vpnc is no longer actively maintained. Since OpenConnect now has ESP support, and since some of these protocols also fall back to operating over TCP when UDP and native ESP aren't available, it may make sense to implement them in OpenConnect now.

Suggestions for other protocols which OpenConnect could usefully implement, are also welcome.

Other enhancements

• WebView support in graphical clients.
  OpenConnect currently screen-scrapes the HTML login pages for protocols like Juniper, which is fragile and error-prone. It would be great if the graphical interfaces like NetworkManager could use a real WebView to show the pages, which would work with JavaScript and various other customisations that the admins often make. This might make an excellent Google Summer of Code project, or would also suit someone just trying to contribute in their spare time.
• Better support for running or emulating the 'Cisco Secure Desktop' trojan.
  The Cisco hostscan tool seems to download and interpret a manifest file from the server and send back results based on the "questions" therein. A native implementation of this would be useful.
• GUI for OS X, perhaps based on Tunnelblick.
• Full Android keystore support.
  OpenConnect's support for the Android keystore predates the Android keystore actually doing anything useful. We assume we can just ask for the private key and be given it. A real keystore would only allow us to perform signature operations using the key, and wouldn't just give it to us. Modern versions of Android can support this, and we should add support for it.
• Mac OS X keychain support.
  Likewise, using keys stored in the OS X keychain would be extremely useful.