Adds key parser for PKCS#8 encoded private keys.

[chr-fritz]

What this PR does / why we need it:
This PR enables the key parser for the ca issuer to use PKCS#8 encoded private keys.

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): No Issue created

Special notes for your reviewer:
The changes in the file generate.go is only required for the tests.

Release note:

Allow to use PKCS#8 encoded private keys in CA issuers.

[jetstack-bot]

Hi @chr-fritz. Thanks for your PR.

I'm waiting for a jetstack or cert-manager member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[munnerz]

From my understanding of this PR, this will allow user-supplied PKCS#8 private keys for all issuer types.

It won't allow users to specify they want PKCS#8 private keys to be generated, but will allow them to be parsed.

This seems reasonable, and like you say, allows user-supplied 'signing CAs' that have a PKCS#8 private key to be used with the CA issuer.

/ok-to-test

[chr-fritz]

Yes thats correct.

I checked the log messages of the e2e tests. All of them are timeouts while connecting to the kubernetes cluster. I let run the tests local. They worked.

/retest

[munnerz]

This looks good to me 😄 thanks!

/lgtm
/approve
/milestone v0.7

[jetstack-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chr-fritz, munnerz

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• OWNERS [munnerz]

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