OpenSSL::SSL#verify_certificate_identity

# File tmp/rubies/ruby-4.0.0/ext/openssl/lib/openssl/ssl.rb, line 249
def verify_certificate_identity(cert, hostname)
  should_verify_common_name = true
  cert.extensions.each{|ext|
    next if ext.oid != "subjectAltName"
    ostr = OpenSSL::ASN1.decode(ext.to_der).value.last
    sequence = OpenSSL::ASN1.decode(ostr.value)
    sequence.value.each{|san|
      case san.tag
      when 2 # dNSName in GeneralName (RFC5280)
        should_verify_common_name = false
        return true if verify_hostname(hostname, san.value)
      when 7 # iPAddress in GeneralName (RFC5280)
        should_verify_common_name = false
        if san.value.size == 4 || san.value.size == 16
          begin
            return true if san.value == IPAddr.new(hostname).hton
          rescue IPAddr::InvalidAddressError
          end
        end
      end
    }
  }
  if should_verify_common_name
    cert.subject.to_a.each{|oid, value|
      if oid == "CN"
        return true if verify_hostname(hostname, value)
      end
    }
  end
  return false
end