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<p class=MsoNormal>Hi all,<o:p></o:p></p>
<p class=MsoNormal>First I’m new with the Pcap sources, I’m trying
to capture SIP messages via my sniffer. I want to do it as fast as I can –
meaning the filter will take place in the driver level, at kernel mode. I’m
using the <span style='font-size:10.0pt;font-family:"Courier New";color:yellow;
background:black;mso-highlight:black'>pcap_compile</span> ( filter_string )
and <span style='font-size:10.0pt;font-family:"Courier New";color:yellow;
background:black;mso-highlight:black'>pcap_setfilter</span><span
style='font-size:10.0pt;font-family:"Courier New";color:yellow'> </span>( ) functions
for setting the driver with my filters. The only idea for doing that was to filter
the SIP messages by using the <b>Filtering Expression Syntax, </b>for example:<b>
</b> Filter the <b>INVITE</b> message <o:p></o:p></p>
<p class=MsoNormal>filter_string = <span style='font-size:10.0pt;font-family:
"Courier New";color:white;background:fuchsia;mso-highlight:fuchsia'>udp[8:4] =
0x494E5649 && udp[12:2] = 0x5445"</span>. If you have a better
idea you are welcome to suggest.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I will appreciate your quick response,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks in advanced,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Gilad<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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