title: Add authenticated/signed attributes with custom oids to PKCS#7 signing?
body: <p>Is there any way to pass extra authenticated attributes for a PKCS#7 signed message using openssl? I'm stuck with the command-line.</p>
  
  <p>I'm currently using :</p>
  
  <pre><code>openssl smime -sign -outform DER -md sha1 -binary -signer my.crt -inkey my.key
  </code></pre>
  
  <p>I did not find any releveant option in openssl cli help.</p>
  
  <hr>
  
  <p>More info :</p>
  
  <p>I'm currently trying to build a SCEP (http://tools.ietf.org/pdf/draft-nourse-scep-23.pdf) server in NodeJS.</p>
  
  <p>SCEP spec requires to build PKCS#7 signed <code>pkiMessages</code>, </p>
  
  <pre><code>The SignerInfo MUST contain a set of authenticatedAttributes (see PKCS#7 [RFC2315] Section 9.2 as well as Section 3.1.1 in this document). All messages MUST contain
  * an SCEP transactionID attribute
  * an SCEP messageType attribute
  * an SCEP senderNonce attribute
  * any attributes required by PKCS#7 [RFC2315] Section 9.2 If the message is a response, it MUST also include
  </code></pre>
  
  <p>Currently my only option has been to wrap <code>openssl</code> functionality through <code>child_process.spawn</code>.</p>