OpenSSL::PKey::EC verification discrepancy between Ruby and JRuby

[laitalaj]

In Ruby, EC signatures are verified with dsa_verify_asn1. However, in this JRuby implementation, such method is missing - instead, EC signature verification is done via the verify method inherited from PKey.

This discrepancy causes problems at least with the ruby-jwt gem's EC functionality, which tries to use dsa_verify_asn1.