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Testing snort rules

Posted on 2010-11-16
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Last Modified: 2013-11-29
When designing a packet to test snort rules, does that packet need to contain all the content listed in the rule. For example a rule that has content:"|C8 4F 32 4B 70 16 D3 01 12 78 5A 47 BF 6E E1 88|"; content:"|00 2E 00 2E 00 5C 00 2E 00 2E 00 5C|"; flags:A+; etc.....?

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Question by:progjm
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btan earned 500 total points
ID: 34152965
check out 2.3.9  Content

@ http://ebook.security-portal.cz/book/snort/writing_rules/chap2.html

Whenever a content option pattern match is performed, the Boyer-Moore pattern match function is called and the (rather computationally expensive) test is performed against the packet contents. If data exactly matching the argument data string is contained anywhere within the packet's payload, the test is successful and the remainder of the rule option tests are performed. Be aware that this test is case sensitive.

Also note option such as 2.3.10  Offset, 2.3.11  Depth and 2.3.12  Nocase that would impact the content matching. 2.3.23  Content-list would be of interest as well as it allows multiple content strings to be specified in the place of a single content option
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