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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Hi Prasant,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I think u need to check <st1:City w:st="on"><st1:place
w:st="on">ur</st1:place></st1:City> filtering string. For protocol filtering
things you need to mention like “proto Protocol name”. I had used
this some time b4 for tcp filtering things so u can use like as follows<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I used “proto \tcp” <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>So u need to use “proto \dns”
instead of “dns” only. Another thing you need to check what is the
pnemonics for dns. Since tcp is a keyword for libpcap so we need to give a “\”
b4 that. U need to check this for dns.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Another thing is dns is layer 4 protocol
so if the above one is not working try with “ protochain \dns”.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Below is the link for <st1:City w:st="on"><st1:place
w:st="on">ur</st1:place></st1:City> help<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><a
href="http://www.winpcap.org/docs/docs_41b/html/group__language.html">http://www.winpcap.org/docs/docs_41b/html/group__language.html</a><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Thanks n Regds<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Umesh<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>IXIA(leader in performance Network testing
domain)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Calcutta<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
winpcap-users-bounces@winpcap.org [mailto:winpcap-users-bounces@winpcap.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Prashant Kasal<br>
<b><span style='font-weight:bold'>Sent:</span></b> Saturday, October 06, 2007
3:11 AM<br>
<b><span style='font-weight:bold'>To:</span></b> winpcap-users@winpcap.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [Winpcap-users] Filtering
for DNS</span></font><o:p></o:p></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Hi All,<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>I'm trying to filter the network packets to get DNS
information<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
10.0pt'>pcap_compile( adhandle, &fcode, "dns", 1, netmask), but
when I executed this line I'm getting the return value < 0; </span></font><o:p></o:p></p>
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<p><font size=2 face="Times New Roman"><span style='font-size:10.0pt'>does
anybody know how to filter the network packets for DNS?</span></font><o:p></o:p></p>
<p><font size=2 face="Times New Roman"><span style='font-size:10.0pt'>Any help
would greatly appricated.</span></font><o:p></o:p></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><br>
-- <br>
Thanks & Regds<br>
Prashanth Kasal <br>
Google Inc.,<br>
1600, Amphitheater<br>
parkway,<br>
Mountain View, CA-94040 <o:p></o:p></span></font></p>
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