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Re: [saag] ASN.1 vs. DER Encoding

Peter Gutmann <pgut001@cs.auckland.ac.nz> Wed, 27 March 2019 09:49 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Nico Williams <nico@cryptonector.com>, Carl Wallace <carl@redhoundsoftware.com>
CC: "saag@ietf.org" <saag@ietf.org>
Thread-Topic: [saag] ASN.1 vs. DER Encoding
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Date: Wed, 27 Mar 2019 09:49:09 +0000
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Subject: Re: [saag] ASN.1 vs. DER Encoding
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Nico Williams <nico@cryptonector.com> writes:

>Something similar can be said of SSHv2's encoding rules.

The ones that arbitrarily mix binary data and comma-delimited text strings?
Of all the encodings I've had to write parsers for, SSH's one scares me the
most.

It's also the one where I've found the most crashes in the other system while
developing the code and getting various bits slightly wrong, e.g. sending
"foo," or ",," as a value, or getting a binary length field slightly wrong in
combination with text-string data.

Peter.

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