_undef in case of failure. Any of <i>oid</i>, <i>sn</i> and <i>ln</i> may be NULL, but not all at once.</p>

<p>OBJ_length() returns the size of the content octets of <i>obj</i>.</p>

<p>OBJ_get0_data() returns a pointer to the content octets of <i>obj</i>. The returned pointer is an internal pointer which <b>must not</b> be freed.</p>

<p>OBJ_add_sigid() creates a new composite &quot;Signature Algorithm&quot; that associates a given NID with two other NIDs - one representing the underlying signature algori