Hi,
I am writing a small utility that converts .etl network trace files produced by netsh trace into pcapng format. The interface information is right at the end of the ETL file, but I need to create
IDBs near the start of the pcapng file. I don’t want to hold a whole converted trace file in memory and I’d prefer not to shuffle the data around in the pcapng file. My plan is:
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Write an “IDB segment” of null bytes where the IDB will go – enough to accomodate the maximum anticipated IDB blocks, say 2 KB
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Once I get to the interface data in the ETL, seek back to the “IDB Segment”
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Write the IDBs
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Pad the “IDB segment” with the equivalent of NoOps
There is no NoOp block type and so I’m thinking of using a Custom Block
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Would using a Custom Block in this way cause problems?
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What value should I use for the Private Enterprise Number (PEN)?
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Is there a better way of doing this?
Thanks and regards…Paul