<tr><td><code>%{FOOBAR}e</code></td>
<td>The contents of the <a href="../env.html">environment
variable</a> <code>FOOBAR</code>.</td></tr>
+
+ <tr><td><code>%{FOOBAR}s</code></td>
+ <td>The contents of the <a href="mod_ssl.html#envvars">SSL environment
+ variable</a> <code>FOOBAR</code>, if <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is enabled.</td></tr>
+
</table>
+ <div class="note"><h3>Note</h3>
+
+ <p>The <code>%s</code> format specifier is only available in
+ Apache 2.1 and later; it can be used instead of <code>%e</code>
+ to avoid the overhead of enabling <code>SSLOptions
+ +StdEnvVars</code>. If <code>SSLOptions +StdEnvVars</code> must
+ be enabled anyway for some other reason, <code>%e</code> will be
+ more efficient than <code>%s</code>.</p>
+
+ </div>
+
<p>When the <code class="directive">Header</code> directive is used with the
<code>add</code>, <code>append</code>, or <code>set</code>
argument, a fourth argument may be used to specify conditions
<tr><td><code>SSL_SERVER_A_SIG</code></td> <td>string</td> <td>Algorithm used for the signature of server's certificate</td></tr>
<tr><td><code>SSL_SERVER_A_KEY</code></td> <td>string</td> <td>Algorithm used for the public key of server's certificate</td></tr>
<tr><td><code>SSL_SERVER_CERT</code></td> <td>string</td> <td>PEM-encoded server certificate</td></tr>
-<tr><td colspan="3">[ where <em>x509</em> is a component of a X.509 DN:
- <code>C,ST,L,O,OU,CN,T,I,G,S,D,UID,Email</code> ]</td></tr>
</table>
+
+<p><em>x509</em> specifies a component of an X.509 DN; one of
+<code>C,ST,L,O,OU,CN,T,I,G,S,D,UID,Email</code>. In Apache 2.1 and
+later, <em>x509</em> may also include a numeric <code>_n</code>
+suffix. If the DN in question contains multiple attributes of the
+same name, this suffix is used as an index to select a particular
+attribute. For example, where the server certificate subject DN
+included two OU fields, <code>SSL_SERVER_S_DN_OU_0</code> and
+<code>SSL_SERVER_S_DN_OU_1</code> could be used to reference each.</p>
+
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="logformats" id="logformats">Custom Log Formats</a></h2>