cert_content = <<EOF
-----BEGIN CERTIFICATE-----
dummy
-----END CERTIFICATE-----
-----BEGIN CERTIFICATE-----
dummy
-----END CERTIFICATE-----
EOF
pkey_content = <<EOF
-----BEGIN EC PARAMETERS-----
dummy
-----END EC PARAMETERS-----
-----BEGIN EC PRIVATE KEY-----
dummy
-----END EC PRIVATE KEY-----
EOF
cert = OpenSSL::X509::Certificate.new(cert_content)
pkey = OpenSSL::PKey::EC.new(pkey_content)
cert.check_private_key(pkey)
cert.subject.to_a.find { |name, _| name == 'CN' }.fetch(1)
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