title: Subject Alternative Name is not copied to signed certificate
body: <p>I use self-signed CA cert to sign other certificates. For some certs I need to specify subject alternative names. I can specify them during request generation (<code>openssl req ...</code>) and I see them in .csr file. Then I sign it with CA cert using </p>
  
  <pre><code>openssl x509 -req -extensions x509v3_config -days 365 -in ${name}.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out ${name}.crt
  </code></pre>
  
  <p>and next sections in openssl.cnf file:</p>
  
  <pre><code>[ x509 ]
  x509_extensions = x509v3_config
  
  [ x509v3_config ]
  copy_extensions = copy
  </code></pre>
  
  <p>but I see no SAN in .crt file.</p>
  
  <p>I know about <a href="https://stackoverflow.com/questions/21297139/how-do-you-sign-certificate-signing-request-with-your-certification-authority">solutions</a> with <code>openssl ca ...</code> command but I have no valid <code>[ca]</code> section and I don't want to copy/paste it without deep understanding what it does. So I hope that exists another solution with <code>openssl x509 ...</code> command.</p>