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90 lines
2.8 KiB
HTML
90 lines
2.8 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<!--Converted with LaTeX2HTML 2002-2-1 (1.70)
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original version by: Nikos Drakos, CBLU, University of Leeds
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* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan
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* with significant contributions from:
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Jens Lippmann, Marek Rouchal, Martin Wilck and others -->
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<HTML>
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<HEAD>
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<TITLE>Scan engine</TITLE>
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<META NAME="description" CONTENT="Scan engine">
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<META NAME="keywords" CONTENT="clamdoc">
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<BODY >
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HREF="node81.html">
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<BR>
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<B> Next:</B> <A NAME="tex2html1376"
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HREF="node81.html">CVD format</A>
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<B> Up:</B> <A NAME="tex2html1372"
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HREF="node77.html">LibClamAV</A>
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<B> Previous:</B> <A NAME="tex2html1366"
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HREF="node79.html">Database reloading</A>
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<B> <A NAME="tex2html1374"
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HREF="node1.html">Contents</A></B>
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<BR>
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<BR></DIV>
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<!--End of Navigation Panel-->
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<H2><A NAME="SECTION00073000000000000000"></A><A NAME="engine"></A>
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<BR>
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Scan engine
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</H2>
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New versions of Clam AntiVirus use a mutation of the Aho-Corasick
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pattern matching algorithm. The algorithm is based a finite state pattern
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matching automaton [<A
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HREF="node90.html#clr">1</A>] and it's a generalization of the famous
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Knuth-Morris-Pratt algorithm. Please take a look at the <code>matcher.h</code>
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for data type definitions. The automaton is represented by a trie. It
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is a rooted tree with some specific properties [<A
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HREF="node90.html#acwww">2</A>]. Every node
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of the trie represents some state of the automaton. In our implementation,
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the node is defined as follows:
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<PRE>
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struct cl_node {
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short int islast;
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struct cli_patt *list;
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int maxpatlen;
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struct node *next[NUM_CHILDS], *trans[NUM_CHILDS], *fail;
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};
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</PRE>
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[To be continued...]
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<P>
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<BR><HR>
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<ADDRESS>
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Tomasz Kojm
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2004-07-22
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</ADDRESS>
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</BODY>
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</HTML>
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