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<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.4</a> > <a href="./">Modules</a></div>
<div id="page-content">
<div id="preamble"><h1>Apache Module mod_tls</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/mod/mod_tls.html" title="English"> en </a></p>
</div>
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>TLS v1.2 and v1.3 implemented in memory-safe Rust via
the rustls library
</td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>tls_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_tls.c</td></tr>
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.4.52 and later</td></tr></table>
<h3>Summary</h3>
<p>
mod_tls is an alternative to <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> for providing https to a server.
It's feature set is a subset, described in more detail below. It can
be used as a companion to <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>, e.g. both modules can be loaded at
the same time.
</p><p>
mod_tls, being written in C, used the Rust implementation of TLS named
<a href="https://github.com/rustls/rustls">rustls</a> via its C interface
<a href="https://github.com/rustls/rustls-ffi">rustls-ffi</a>. This gives
<em>memory safe</em> cryptography and protocol handling at comparable
performance.
</p><p>
It can be configured for frontend and backend connections. The configuration
directive have been kept mostly similar to <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> ones.
</p>
</div>
<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3>Topics</h3>
<ul id="topics">
<li><img alt="" src="../images/down.gif" /> <a href="#vhost_context">TLS in a VirtualHost context</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#comparison">Feature Comparison with mod_ssl</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#protocols">TLS Protocols</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#ciphers">TLS Ciphers</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#vhosts">Virtual Hosts</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#ACME">ACME Certificates</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#OCSP">OCSP Stapling</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#variables">TLS Variables</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#certificates">Client Certificates</a></li>
</ul><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="../images/down.gif" /> <a href="#tlscertificate">TLSCertificate</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsciphersprefer">TLSCiphersPrefer</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlscipherssuppress">TLSCiphersSuppress</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsengine">TLSEngine</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlshonorclientorder">TLSHonorClientOrder</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsoptions">TLSOptions</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsprotocol">TLSProtocol</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsproxyca">TLSProxyCA</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsproxyciphersprefer">TLSProxyCiphersPrefer</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsproxycipherssuppress">TLSProxyCiphersSuppress</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsproxyengine">TLSProxyEngine</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsproxymachinecertificate">TLSProxyMachineCertificate</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsproxyprotocol">TLSProxyProtocol</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlssessioncache">TLSSessionCache</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#tlsstrictsni">TLSStrictSNI</a></li>
</ul>
<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&list_id=144532&product=Apache%20httpd-2&query_format=specific&order=changeddate%20DESC%2Cpriority%2Cbug_severity&component=mod_tls">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&component=mod_tls">Report a bug</a></li></ul><h3>See also</h3>
<ul class="seealso">
<li><a href="#comments_section">Comments</a></li></ul></div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="vhost_context" id="vhost_context">TLS in a VirtualHost context</a></h2>
<pre class="prettyprint lang-config">Listen 443
TLSEngine 443
<VirtualHost *:443>
ServerName example.net
TLSCertificate file_with_certificate.pem file_with_key.pem
...
</VirtualHost></pre>
<p>
The above is a minimal configuration. Instead of enabling mod_tls
in every virtual host, the port for incoming TLS connections is
specified.
</p><p>
You cannot mix virtual hosts with <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> and mod_tls on the same
port. It's either or. SNI and ALPN are supported. You may use several
virtual hosts on the same port and a mix of protocols like http/1.1
and h2.
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="comparison" id="comparison">Feature Comparison with mod_ssl</a></h2>
<p>
The table below gives a comparison of feature between
<code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> and mod_tls. If a feature of <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is no listed here,
it is not supported by mod_tls. The one difference, probably most relevant
is the lack for client certificate support in the current version of
mod_tls.
</p>
<table>
<tr><th>Feature</th><th>mod_ssl</th><th>mod_tls</th><th>Comment</th></tr>
<tr><td>Frontend TLS</td><td>yes</td><td>yes</td><td /></tr>
<tr><td>Backend TLS</td><td>yes</td><td>yes</td><td /></tr>
<tr><td>TLS v1.3</td><td>yes*</td><td>yes</td><td>*)with recent OpenSSL</td></tr>
<tr><td>TLS v1.2</td><td>yes</td><td>yes</td><td /></tr>
<tr><td>TLS v1.0</td><td>yes*</td><td>no</td><td>*)if enabled in OpenSSL</td></tr>
<tr><td>SNI Virtual Hosts</td><td>yes</td><td>yes</td><td /></tr>
<tr><td>Client Certificates</td><td>yes</td><td>no</td><td /></tr>
<tr><td>Machine Certificates for Backend</td><td>yes</td><td>yes</td><td /></tr>
<tr><td>OCSP Stapling</td><td>yes</td><td>yes*</td><td>*)via <code class="module"><a href="../mod/mod_md.html">mod_md</a></code></td></tr>
<tr><td>Backend OCSP check</td><td>yes</td><td>no*</td><td>*)stapling will be verified</td></tr>
<tr><td>TLS version to allow</td><td>min-max</td><td>min</td><td /></tr>
<tr><td>TLS ciphers</td><td>exclusive list</td><td>preferred/suppressed</td><td /></tr>
<tr><td>TLS cipher ordering</td><td>client/server</td><td>client/server</td><td /></tr>
<tr><td>TLS sessions</td><td>yes</td><td>yes</td><td /></tr>
<tr><td>SNI strictness</td><td>default no</td><td>default yes</td><td /></tr>
<tr><td>Option EnvVars</td><td>exhaustive</td><td>limited*</td><td>*)see var list</td></tr>
<tr><td>Option ExportCertData</td><td>client+server</td><td>server</td><td /></tr>
<tr><td>Backend CA</td><td>file/dir</td><td>file</td><td /></tr>
<tr><td>Revocation CRLs</td><td>yes</td><td>no</td><td /></tr>
<tr><td>TLS Renegotiation</td><td>yes*</td><td>no</td><td>*)in TLS v1.2</td></tr>
<tr><td>Encrypted Cert Keys</td><td>yes</td><td>no</td><td /></tr>
</table>
<p>
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="protocols" id="protocols">TLS Protocols</a></h2>
<p>
mod_tls supports TLS protocol version 1.2 and 1.3. Should there ever be
a version 1.4 and <code>rustls</code> supports it, it will be available as well.
</p>
<p>
In mod_tls, you configure the <em>minimum</em> version to use, never the maximum:
</p>
<pre class="prettyprint lang-config">TLSProtocol TLSv1.3+</pre>
<p>
This allows only version 1.3 and whatever may be its successor one day when talking
to your server or to a particular virtual host.
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="ciphers" id="ciphers">TLS Ciphers</a></h2>
<p>
The list of TLS ciphers supported in the <code>rustls</code> library,
can be found <a href="https://docs.rs/rustls/">here</a>. All TLS v1.3
ciphers are supported. For TLS v1.2, only ciphers that rustls considers
secure are available.
</p><p>
mod_tls supports the following names for TLS ciphers:
</p>
<ol>
<li>
The <a href="https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4">IANA assigned name</a>
which uses `_` to separate parts. Example: <code>TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384</code>
</li>
<li>
The OpenSSL name, using `-` as separator (for 1.2). Example: <code>ECDHE-ECDSA-AES256-SHA384</code>.
Such names often appear in documentation. `mod_tls` defines them for all TLS v1.2 ciphers.
For TLS v1.3 ciphers, names starting with <code>TLS13_</code> are also supported.
</li>
<li>
The <a href="https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-4">IANA assigned identifier</a>,
which is a 16-bit numeric value. Example: <code>0xc024</code>.
You can use this in configurations as <code>TLS_CIPHER_0xc024</code>.
</li>
</ol>
<p>
You can configure a preference for ciphers, which means they will be used
for clients that support them. If you do not configure a preference, <code>rustls</code>
will use the one that it considers best. This is recommended.
</p>
<p>
Should you nevertheless have the need to prefer one cipher over another, you
may configure it like this:
</p>
<pre class="prettyprint lang-config">TLSCiphersPrefer ECDHE-ECDSA-AES256-SHA384
# or several
TLSCiphersPrefer ECDHE-ECDSA-AES256-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305</pre>
<p>
If you name a cipher that is unknown, the configuration will fail.
If you name a cipher is not supported by <code>rustls</code> (or no
longer supported in an updated version of <code>rustls</code> for security
reasons), mod_tls will log a <code>WARNING</code>, but continue to work.
</p>
<p>
A similar mechanism exists, if you want to disable a particular cipher:
</p>
<pre class="prettyprint lang-config">TLSCipherSuppress ECDHE-ECDSA-AES256-SHA384</pre>
<p>
A suppressed cipher will not longer be used.
If you name a cipher that is unknown, the configuration will fail.
If you name a cipher is not supported by <code>rustls</code> (or no
longer supported in an updated version of <code>rustls</code> for security
reasons), mod_tls will log a <code>WARNING</code>, but continue to work.
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="vhosts" id="vhosts">Virtual Hosts</a></h2>
<p>
mod_tls uses the SNI (Server Name Indicator) to select one of the
configured virtual hosts that match the port being served. Should
the client not provide an SNI, the <em>first</em> configured
virtual host will be selected. If the client <em>does</em> provide
an SNI (as all today's clients do), it <em>must</em> match one
virtual host (<code class="directive"><a href="../mod/core.html#servername">ServerName</a></code> or
<code class="directive"><a href="../mod/core.html#serveralias">ServerAlias</a></code>)
or the connection will fail.
</p>
<p>
As with <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>, you may specify ciphers and protocol
versions for the base server (global) and/or individual virtual hosts
that are selected via SNI by the client.
</p>
<pre class="prettyprint lang-config">Listen 443
TLSEngine 443
<VirtualHost *:443>
ServerName example1.net
TLSCertificate example1-cert.pem
...
</VirtualHost>
<VirtualHost *:443>
ServerName example2.net
TLSCertificate example2-cert.pem
...
TLSProtocol v1.3+
</VirtualHost></pre>
<p>
The example above show different TLS settings for virtual hosts on the
same port. This is supported. <code>example1</code> can be contacted via
all TLS versions and <code>example2</code> only allows v1.3 or later.
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="ACME" id="ACME">ACME Certificates</a></h2>
<p>
ACME certificates via <code class="module"><a href="../mod/mod_md.html">mod_md</a></code> are supported, just as
for <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>. A minimal configuration:
</p>
<pre class="prettyprint lang-config">Listen 443
TLSEngine 443
MDomain example.net
<VirtualHost *:443>
ServerName example.net
...
</VirtualHost></pre>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="OCSP" id="OCSP">OCSP Stapling</a></h2>
<p>
mod_tls has no own implementation to retrieve OCSP information for
a certificate. However, it will use such for Stapling if it is provided
by <code class="module"><a href="../mod/mod_md.html">mod_md</a></code>. See <code class="module"><a href="../mod/mod_md.html">mod_md</a></code>'s documentation
on how to enable this.
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="variables" id="variables">TLS Variables</a></h2>
<p>
Via the directive <code class="directive"><a href="#tlsoptions">TLSOptions</a></code>, several variables
are placed into the environment of requests and can be inspected, for
example in a CGI script.
</p>
<p>
The variable names are given by <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>. Note that these
are only a subset of the many variables that <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> exposes.
</p>
<table>
<tr><th>Variable</th><th>TLSOption</th><th>Description</th></tr>
<tr><td>SSL_TLS_SNI</td><td>*</td><td>the server name indicator (SNI) send by the client</td></tr>
<tr><td>SSL_PROTOCOL</td><td>*</td><td>the TLS protocol negotiated</td></tr>
<tr><td>SSL_CIPHER</td><td>*</td><td>the name of the TLS cipher negotiated</td></tr>
<tr><td>SSL_VERSION_INTERFACE</td><td>StdEnvVars</td><td>the module version</td></tr>
<tr><td>SSL_VERSION_LIBRARY</td><td>StdEnvVars</td><td>the rustls-ffi version</td></tr>
<tr><td>SSL_SECURE_RENEG</td><td>StdEnvVars</td><td>always `false`</td></tr>
<tr><td>SSL_COMPRESS_METHOD</td><td>StdEnvVars</td><td>always `false`</td></tr>
<tr><td>SSL_CIPHER_EXPORT</td><td>StdEnvVars</td><td>always `false`</td></tr>
<tr><td>SSL_CLIENT_VERIFY</td><td>StdEnvVars</td><td>always `false`</td></tr>
<tr><td>SSL_SESSION_RESUMED</td><td>StdEnvVars</td><td>either `Resumed` if a known TLS session id was presented by the client or `Initial` otherwise</td></tr>
<tr><td>SSL_SERVER_CERT</td><td>ExportCertData</td><td>the selected server certificate in PEM format</td></tr>
</table>
<p>
The variable <code>SSL_SESSION_ID</code> is intentionally not supported as
it contains sensitive information.
</p>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="certificates" id="certificates">Client Certificates</a></h2>
<p>
While <code>rustls</code> supports client certificates in principle, parts
of the infrastructure to make <em>use</em> of these in a server are not
offered.
</p>
<p>
Among these features are: revocation lists, inspection of certificate
extensions and the matched issuer chain for OCSP validation. Without these,
revocation of client certificates is not possible. Offering authentication
without revocation is not considered an option.
</p>
<p>
Work will continue on this and client certificate support may become
available in a future release.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSCertificate" id="TLSCertificate">TLSCertificate</a> <a name="tlscertificate" id="tlscertificate">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>adds a certificate and key (PEM encoded) to a server/virtual host.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSCertificate <em>cert_file</em> [<em>key_file</em>]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
If you do not specify a separate key file, the key is assumed to also be
found in the first file. You may add more than one certificate to a
server/virtual host. The first certificate suitable for a client is then chosen.
</p><p>
The path can be specified relative to the server root.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSCiphersPrefer" id="TLSCiphersPrefer">TLSCiphersPrefer</a> <a name="tlsciphersprefer" id="tlsciphersprefer">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>defines ciphers that are preferred.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSCiphersPrefer <em>cipher(-list)</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
This will not disable any ciphers supported by `rustls`. If you
specify a cipher that is completely unknown, the configuration will
fail. If you specify a cipher that is known but not supported by `rustls`,
a warning will be logged but the server will continue.
</p><p>
</p>
<div class="example"><h3>Example</h3><pre class="prettyprint lang-config">TLSCiphersPrefer ECDHE-ECDSA-AES256-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305</pre>
</div>
<p>
The example gives 2 ciphers preference over others, in the
order they are mentioned.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSCiphersSuppress" id="TLSCiphersSuppress">TLSCiphersSuppress</a> <a name="tlscipherssuppress" id="tlscipherssuppress">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>defines ciphers that are not to be used.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSCiphersSuppress <em>cipher(-list)</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
This will not disable any unmentioned ciphers supported by `rustls`.
If you specify a cipher that is completely unknown, the configuration will fail.
If you specify a cipher that is known but not supported by `rustls`,
a warning will be logged but the server will continue.
</p><p>
</p>
<div class="example"><h3>Example</h3><pre class="prettyprint lang-config">TLSCiphersSuppress ECDHE-ECDSA-CHACHA20-POLY1305</pre>
</div>
<p>
The example removes a cipher for use in connections.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSEngine" id="TLSEngine">TLSEngine</a> <a name="tlsengine" id="tlsengine">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>defines on which address+port the module shall handle incoming connections.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSEngine [<em>address</em>:]<em>port</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
This is set on a global level, not in individual <code class="directive"><a href="../mod/core.html#virtualhost"><VirtualHost></a></code>s.
It will affect all <code class="directive"><a href="../mod/core.html#virtualhost"><VirtualHost></a></code>
that match the specified address/port.
You can use <code class="directive">TLSEngine</code> several times to use more than one address/port.
</p><p>
</p>
<div class="example"><h3>Example</h3><pre class="prettyprint lang-config">TLSEngine 443</pre>
</div>
<p>
The example tells mod_tls to handle incoming connection on port 443 for
all listeners.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSHonorClientOrder" id="TLSHonorClientOrder">TLSHonorClientOrder</a> <a name="tlshonorclientorder" id="tlshonorclientorder">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>determines if the order of ciphers supported by the client is honored</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSHonorClientOrder on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TLSHonorClientOrder on</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
<code class="directive">TLSHonorClientOrder</code> determines if the order of ciphers
supported by the client is honored.
</p><p>
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSOptions" id="TLSOptions">TLSOptions</a> <a name="tlsoptions" id="tlsoptions">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>enables SSL variables for requests.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSOptions [+|-]<em>option</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
<code class="directive">TLSOptions</code> is analog to <code class="directive"><a href="../mod/mod_ssl.html#ssloptions">SSLOptions</a></code> in <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>.
It can be set per directory/location and `option` can be:
</p>
<ul>
<li>`StdEnvVars`: adds more variables to the requests environment,
as forwarded for example to CGI processing and other applications.
</li>
<li>`ExportCertData`: adds certificate related variables to the request environment.
</li>
<li>`Defaults`: resets all options to their default values.</li>
</ul>
<p>
Adding variables to a request environment adds overhead, especially
when certificates need to be inspected and fields extracted.
Therefore most variables are not set by default.
</p>
<p>
You can configure <code class="directive">TLSOptions</code> per location or generally on a
server/virtual host. Prefixing an option with `-` disables this
option while leaving others unchanged.
A `+` prefix is the same as writing the option without one.
</p>
<p>
The `Defaults` value can be used to reset any options that are
inherited from other locations or the virtual host/server.
</p>
<div class="example"><h3>Example</h3><pre class="prettyprint lang-config"><Location /myplace/app>
TLSOptions Defaults StdEnvVars
...
</Location></pre>
</div>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProtocol" id="TLSProtocol">TLSProtocol</a> <a name="tlsprotocol" id="tlsprotocol">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>specifies the minimum version of the TLS protocol to use.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProtocol <em>version</em>+</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TLSProtocol v1.2+</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
The default is `v1.2+`. Settings this to `v1.3+` would disable TLSv1.2.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProxyCA" id="TLSProxyCA">TLSProxyCA</a> <a name="tlsproxyca" id="tlsproxyca">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>sets the root certificates to validate the backend server with.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProxyCA <em>file.pem</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, proxy section</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProxyCiphersPrefer" id="TLSProxyCiphersPrefer">TLSProxyCiphersPrefer</a> <a name="tlsproxyciphersprefer" id="tlsproxyciphersprefer">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>defines ciphers that are preferred for a proxy connection.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProxyCiphersPrefer <em>cipher(-list)</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, proxy section</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
This will not disable any ciphers supported by `rustls`.
If you specify a cipher that is completely unknown, the configuration will fail.
If you specify a cipher that is known but not supported by `rustls`,
a warning will be logged but the server will continue.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProxyCiphersSuppress" id="TLSProxyCiphersSuppress">TLSProxyCiphersSuppress</a> <a name="tlsproxycipherssuppress" id="tlsproxycipherssuppress">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>defines ciphers that are not to be used for a proxy connection.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProxyCiphersSuppress <em>cipher(-list)</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, proxy section</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
This will not disable any unmentioned ciphers supported by `rustls`.
If you specify a cipher that is completely unknown, the configuration will fail.
If you specify a cipher that is known but not supported by `rustls`,
a warning will be logged but the server will continue.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProxyEngine" id="TLSProxyEngine">TLSProxyEngine</a> <a name="tlsproxyengine" id="tlsproxyengine">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>enables TLS for backend connections.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProxyEngine on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, proxy section</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
<code class="directive">TLSProxyEngine</code> is analog to <code class="directive"><a href="../mod/mod_ssl.html#sslproxyengine">SSLProxyEngine</a></code> in <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>.
</p><p>
This can be used in a server/virtual host or <code class="directive"><a href="../mod/mod_proxy.html#proxy"><Proxy></a></code> section to
enable the module for outgoing connections using <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProxyMachineCertificate" id="TLSProxyMachineCertificate">TLSProxyMachineCertificate</a> <a name="tlsproxymachinecertificate" id="tlsproxymachinecertificate">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>adds a certificate and key file (PEM encoded) to a proxy setup.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProxyMachineCertificate <em>cert_file</em> [<em>key_file</em>]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, proxy section</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
The certificate is used to authenticate against a proxied backend server.
</p><p>
If you do not specify a separate key file, the key is assumed to also be
found in the first file. You may add more than one certificate to a proxy
setup. The first certificate suitable for a proxy connection to a backend
is then chosen by <code>rustls</code>.
</p>
<p>
The path can be specified relative to the server root.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSProxyProtocol" id="TLSProxyProtocol">TLSProxyProtocol</a> <a name="tlsproxyprotocol" id="tlsproxyprotocol">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>specifies the minimum version of the TLS protocol to use in proxy connections.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSProxyProtocol <em>version</em>+</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TLSProxyProtocol v1.2+</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, proxy section</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
The default is `v1.2+`. Settings this to `v1.3+` would disable TLSv1.2.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSSessionCache" id="TLSSessionCache">TLSSessionCache</a> <a name="tlssessioncache" id="tlssessioncache">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>specifies the cache for TLS session resumption.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSSessionCache <em>cache-spec</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
This uses a cache on the server side to allow clients to resume connections.
</p><p>
You can set this to `none` or define a cache as in the <code class="directive"><a href="../mod/mod_ssl.html#sslsessioncache">SSLSessionCache</a></code>
directive of <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code>.
</p><p>
If not configured, `mod_tls` will try to create a shared memory cache on its own,
using `shmcb:tls/session-cache` as specification.
Should that fail, a warning is logged, but the server continues.
</p>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="TLSStrictSNI" id="TLSStrictSNI">TLSStrictSNI</a> <a name="tlsstrictsni" id="tlsstrictsni">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>enforces exact matches of client server indicators (SNI) against host names.</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>TLSStrictSNI on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>TLSStrictSNI on</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_tls</td></tr>
</table>
<p>
Client connections using SNI will be unsuccessful if no match is found.
</p>
</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_tls.html" title="English"> en </a></p>
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