Modifying DNP3 Content
Chamara Devanarayana via Snort-devel <[email protected]> Wed, 18 Sep 2019 21:00:46 +0000
| Newsgroups | gmane.comp.security.ids.snort.devel |
|---|---|
| Message-ID | <[email protected]> |
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Hi,
I tried to use SNORT inline to modify DNP3 application data. Although SNORT=
modified the data it did not modify the CRC which is there after the first=
8 bytes and then after each 16 bytes. Therefore, there was a CRC error at =
the DNP3 Master. I modified the sp_replace to handle this and it was workin=
g after that. Is it possible to contribute the changes that I made in the S=
NORT repo? If so what is the procedure for doing so?
Thanks,
Best regards,
Chamara Devanarayana
Simulation Specialist
RTDS Technologies Inc.
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<p class=3D"MsoNormal">Hi,<o:p></o:p></p>
<p class=3D"MsoNormal">I tried to use SNORT inline to modify DNP3 applicati=
on data. Although SNORT modified the data it did not modify the CRC which i=
s there after the first 8 bytes and then after each 16 bytes. Therefore, th=
ere was a CRC error at the DNP3 Master.
I modified the sp_replace to handle this and it was working after that. Is=
it possible to contribute the changes that I made in the SNORT repo? If so=
what is the procedure for doing so?<o:p></o:p></p>
<p class=3D"MsoNormal">Thanks,<o:p></o:p></p>
<p class=3D"MsoNormal">Best regards,<o:p></o:p></p>
<p class=3D"MsoNormal"><b><span style=3D"mso-fareast-language:EN-CA">Chamar=
a Devanarayana<o:p></o:p></span></b></p>
<p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-CA">Simulatio=
n Specialist<o:p></o:p></span></p>
<p class=3D"MsoNormal"><span style=3D"mso-fareast-language:EN-CA">RTDS Tech=
nologies Inc.<o:p></o:p></span></p>
<p class=3D"MsoNormal"><o:p> </o:p></p>
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