mirror of
https://github.com/Cisco-Talos/clamav.git
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91 lines
2.9 KiB
HTML
91 lines
2.9 KiB
HTML
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
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<!--Converted with LaTeX2HTML 2K.1beta (1.48)
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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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<META NAME="resource-type" CONTENT="document">
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<META NAME="distribution" CONTENT="global">
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<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
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<META NAME="Generator" CONTENT="LaTeX2HTML v2K.1beta">
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<META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css">
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<LINK REL="STYLESHEET" HREF="clamdoc.css">
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<LINK REL="next" HREF="node66.html">
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<LINK REL="previous" HREF="node64.html">
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<LINK REL="up" HREF="node62.html">
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<LINK REL="next" HREF="node66.html">
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</HEAD>
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<BODY >
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<!--Navigation Panel-->
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<A NAME="tex2html1093"
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HREF="node66.html">
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<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next"
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SRC="/usr/share/latex2html/icons/next.png"></A>
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<A NAME="tex2html1089"
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HREF="node62.html">
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<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up"
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SRC="/usr/share/latex2html/icons/up.png"></A>
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<A NAME="tex2html1083"
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HREF="node64.html">
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<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous"
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SRC="/usr/share/latex2html/icons/prev.png"></A>
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<A NAME="tex2html1091"
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HREF="node1.html">
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<IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents"
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SRC="/usr/share/latex2html/icons/contents.png"></A>
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<BR>
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<B> Next:</B> <A NAME="tex2html1094"
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HREF="node66.html">CVD format</A>
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<B> Up:</B> <A NAME="tex2html1090"
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HREF="node62.html">LibClamAV</A>
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<B> Previous:</B> <A NAME="tex2html1084"
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HREF="node64.html">Database reloading</A>
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  <B> <A NAME="tex2html1092"
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HREF="node1.html">Contents</A></B>
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<BR>
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<BR>
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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="node75.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="node75.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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2004-03-13
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</ADDRESS>
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</BODY>
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</HTML>
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