distance, within, and negated matches

[L0rd Ch0de1m0rt <l0rdch0de1m0rt () gmail com>]

Hello.  Let's say I want to alert on 'foo' in the http uri but not if 'bar'
or 'xyz' come after it and are within 16 bytes. I have:

content:"foo"; http_uri; content:!"bar"; http_uri; within:16;
conent:!"xyz"; http_uri; within:16;

Will this work?

Basically, if you have two negated content matches in a row with 'within',
do they both match relative to the last non-negated content match or does
the buffer pointer move with the first negated content match and apply to
the second negated content match?  If the latter, I guess you would have to
do something like this, right?:

content:"foo"; http_uri; content:!"bar"; http_uri; within:16;
conent:!"xyz"; http_uri; within:13;

Or would you have to rematch like this?:

content:"foo"; http_uri; content:!"bar"; http_uri; within:16;
content:"foo"; http_uri; conent:!"xyz"; http_uri; within:16;

Cheers,

Lord C.

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