Re: [Cbor] [COSE] CBOR magic number, file format and tags

Carsten Bormann <cabo@tzi.org> Sat, 23 January 2021 20:42 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Sat, 23 Jan 2021 21:42:40 +0100
Cc: cbor@ietf.org, "Dale R. Worley" <worley@ariadne.com>, Michael Richardson <mcr@sandelman.ca>, doug@ewellic.org
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To: Laurence Lundblade <lgl@island-resort.com>
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Subject: Re: [Cbor] [COSE] CBOR magic number, file format and tags
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On 2021-01-23, at 21:36, Laurence Lundblade <lgl@island-resort.com> wrote:
> 
> You could take d9 d9 f7 d8 30 to be the magic number for a compressed CBOR cert. The 8b is to open the array for step 1) above. When you want to put the compressed CBOR cert into a protocol message field that needs no tagging you can just exclude those five bytes. When you take it out of a protocol message and put it in a file, you add those five bytes.

… or six bytes!

(Turning the over-the-air cert into a CBOR sequence again.)

Grüße, Carsten