Add functionality to parse pubkey from Fulcio cert

[lkatalin]

Signed-off-by: Lily Sturmann lsturman@redhat.com

[lukehinds]

Lgtm.

[flavio]

I'm against that, because this would cause openssl to become a runtime dependency, making impossible for consumers of this library to build their libraries/binaries as pure Rust.

If you want I can help with the rewrite of this code using the crates that are already being consumed.

BTW: currently openssl is a development dependency because it's used to create x509 certificates inside of the unit tests. This code could be rewritten using picky-rs, but I didn't consider that worth the effort.

[lukehinds]

I had not noticed that, incorrectly read it as a version bump. Agree with @flavio here, a lot of minimal images ship without openssl.

[lkatalin]

Sure, I can rewrite it with one of the existing crates probably after this week... stay tuned!

[flavio]

Thanks a lot @lkatalin for understanding the issue