Wireshark-dev: [Wireshark-dev] ASN.1 bit string alignment
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From: "Neil Piercy" <Neil.Piercy@xxxxxxxxxxxx>
Date: Mon, 22 Mar 2010 18:30:30 -0000
In 1.0.x PER ASN.1 bit strings used to be padded in the MSBs, (e.g.
extract from an RRC message):

dl-HFN: 00000004 [bit length 25]

Since 1.2.x they appear to be padded in the LSBs (e.g. the same
extract):

dl-HFN: 00000200 [bit length 25]

The value carried in both cases above is meant to be 4.

Is this a deliberate change?

I know bit strings are of arbitrary length, therefore a "natural"
representation is challenging, but I find the above counter-intuitive.

Neil





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