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<B> Next:</B> <A NAME="tex2html1290"
HREF="node76.html">CVD format</A>
<B> Up:</B> <A NAME="tex2html1286"
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<H2><A NAME="SECTION00073000000000000000"></A><A NAME="engine"></A>
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Scan engine |
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New versions of Clam AntiVirus use a mutation of the Aho-Corasick
pattern matching algorithm. The algorithm is based a finite state pattern
matching automaton [<A
HREF="node85.html#clr">1</A>] and it's a generalization of the famous
Knuth-Morris-Pratt algorithm. Please take a look at the <code>matcher.h</code>
for data type definitions. The automaton is represented by a trie. It
is a rooted tree with some specific properties [<A
HREF="node85.html#acwww">2</A>]. Every node
of the trie represents some state of the automaton. In our implementation,
the node is defined as follows: |
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<PRE> |
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struct cl_node {
short int islast;
struct cli_patt *list;
int maxpatlen;
struct node *next[NUM_CHILDS], *trans[NUM_CHILDS], *fail;
}; |
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</PRE> |
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[To be continued...] |
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<ADDRESS>
Tomasz Kojm |
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2004-06-14 |
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</ADDRESS>
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