Add support for login via certificate

[avandecreme]

The first commit is cherry picked from #62

The second one is specific to this PR and allow one to use certificate to login to vault.

[Haennetz]

Hey thanks for your pull request. It would be nice if you can add a test for the certificate login. I merged #62 can you rebase your branch then the checks should be able to pass.

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[avandecreme]

I added two commits.
The first one is implementing the tests. The second one is just to show how having jmgilman/dockertest-server#15 merged could clean up this PR.

I committed the keys and certificates as well as the method to generate them. I see that gitguardian is not happy about it even though those are just test certificates.

I guess we could generate new certificates on every test run, provided we can run openssl in the runner. What do you think?

[Haennetz]

Yes I think generating a new certificate each time would be the best solution for that.
We can use rcgen as a dev dependency and create the certificate with it.

[avandecreme]

Yes I think generating a new certificate each time would be the best solution for that. We can use rcgen as a dev dependency and create the certificate with it.

Done

[Haennetz]

Hey tanks for implementing this. The test is failing at the moment because the nativ-tls feature didn't support pam only. It requires pkcs8 or pkcs12.

[avandecreme]

I added a commit to disable the test with native-tls since vaultrs does not support client certificates with it anyway. See

vaultrs/src/client.rs

Line 298 in 34e3874

error!("Client certificates not implemented for native-tls");

[Haennetz]

With the suggestions we should get rid of the warnings.

[avandecreme]

Suggestions applied

[Haennetz]

Thanks 👍