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<h1 id="dynamic-configuration-dconf">Dynamic Configuration (DCONF)</h1>
<p>ClamAV supports a limited set of configuration options that may be enabled or disabled via settings in the <code>*.cfg</code> database. At this time, these settings are distributed in <code>daily.cfg</code>.</p>
<p>The goal of DCONF is to enable the ClamAV team to rapidly disable new or experimental features for specific ClamAV versions if a significant defect is discovered after release.</p>
<p>This database is small, and the settings are largely vestigial. The team has not had a need to disable many features in a long time, and so the ClamAV versions in the settings at this time should no longer be in use.</p>
<p>The strings and values referenced in <code>daily.cfg</code> are best cross-referenced with the macros and structures defined here:</p>
<ul>
<li><a href="https://github.com/Cisco-Talos/clamav-devel/blob/dev/0.101/libclamav/dconf.h#L49" class="uri">https://github.com/Cisco-Talos/clamav-devel/blob/dev/0.101/libclamav/dconf.h#L49</a></li>
<li><a href="https://github.com/Cisco-Talos/clamav-devel/blob/dev/0.101/libclamav/dconf.c#L54" class="uri">https://github.com/Cisco-Talos/clamav-devel/blob/dev/0.101/libclamav/dconf.c#L54</a></li>
</ul>
<p>The format for a DCONF signature is:</p>
<pre><code>Category:Flags:StartFlevel:EndFlevel</code></pre>
<p><code>Category</code> may be one of:</p>
<ul>
<li>PE</li>
<li>ELF</li>
<li>MACHO</li>
<li>ARCHIVE</li>
<li>DOCUMENT</li>
<li>MAIL</li>
<li>OTHER</li>
<li>PHISHING</li>
<li>BYTECODE</li>
<li>STATS</li>
<li>PCRE</li>
</ul>
<p><code>Flags</code>:</p>
<p>Every feature that may be configured via DCONF is listed in <code>struct dconf_module modules</code> in <code>libclamav/dconf.c</code>. Any given feature may be default-on or default-off. Default-on features have the 4th field set to a <code>1</code> and default off are set to <code>0</code>. The <code>Flags</code> field for a given <code>Category</code> overrides the defaults for all of the options listed under that category.</p>
<p>A settings of <code>0x0</code>, for example, means that all options the category be disabled.</p>
<p>The macros listed in <code>libclamav/dconf.h</code> will help you identify which bits to set to get the desired results.</p>
<p><code>StartFlevel</code>:</p>
<p>This is the <a href="FunctionalityLevels.html">FLEVEL</a> of the minimum ClamAV engine for which you want the settings to be in effect.</p>
<p><code>EndFlevel</code>:</p>
<p>This is the <a href="FunctionalityLevels.html">FLEVEL</a> of the maximum ClamAV engine for which you want the settings to be in effect. You may wish to select <code>255</code> to override the defaults of future releases.</p>
<h2 id="example">Example</h2>
<p>Consider the <code>OTHER_CONF_PDFNAMEOBJ</code> option in the <code>category</code> <code>OTHER</code>.</p>
<div class="sourceCode"><pre class="sourceCode c"><code class="sourceCode c"><span class="pp">#define OTHER_CONF_UUENC 0x1 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_SCRENC 0x2 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_RIFF 0x4 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_JPEG 0x8 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_CRYPTFF 0x10 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_DLP 0x20 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_MYDOOMLOG 0x40 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_PREFILTERING 0x80 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_PDFNAMEOBJ 0x100 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_PRTNINTXN 0x200 </span><span class="co">// Default: 1</span>
<span class="pp">#define OTHER_CONF_LZW 0x400 </span><span class="co">// Default: 1</span></code></pre></div>
<p>All of the <code>OTHER</code> options, including <code>OTHER_CONF_PDFNAMEOBJ</code> are default-on. To disable the option for ClamAV v0.100.X but leave the other options in their default settings, we would need to set the flags to:</p>
<pre class="binary"><code>0110 1111 1111
^pdfnameobj off</code></pre>
<p>Or in hex: <code>0x6FF</code></p>
<p>The example setting to place in <code>daily.cfg</code> then woudl be:</p>
<pre><code>OTHER:0x6FF:90:99</code></pre>
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