Add function to get curve name from ECDSA certificate

[steepnought]

Please add a function to get the curve name from an ECDSA certificate. I couldn't find any in the documentation.

[h-vn]

Do you know which OpenSSL API functions would be needed for this? If you do, then I'd know quicker what to expose. For example, is this the information you are looking for: https://wiki.openssl.org/index.php/File:Cert-with-flag.png

[steepnought]

I am looking for the name of the curve that was used to create the key via -pkeyopt ec_paramgen_curve:$curve. This seems to be the ASN1 OID in the openssl output.

Unfortunately, I don't know what is needed to get this information.