Re: [TLS] Suspicious behaviour of TLS server implementations

Ilari Liusvaara <ilariliusvaara@welho.com> Wed, 21 September 2016 16:12 UTC

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Date: Wed, 21 Sep 2016 19:12:39 +0300
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: tls@ietf.org
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Subject: Re: [TLS] Suspicious behaviour of TLS server implementations
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On Wed, Sep 21, 2016 at 03:53:33PM +0000, Peter Gutmann wrote:
> Andreas Walz <andreas.walz@hs-offenburg.de>; writes:
> 
>   Error: Couldn't connect to Amazon because <explanation for 
>          decoding_error alert>.
> 
> What would you put for the explanation for this case?  And if you say "decode
> error" the user's response will be to switch to some less buggy software that
> doesn't have problems connecting.

Well, valid response...
 
> If you're writing a strict validating protocol parser than disconnecting in
> this case is a valid response, but if it's software that will be used by
> actual humans then failing a connect based on something like this makes no
> sense.

decode_error only happens if either end is buggy (the receiver parsing
can also be buggy), or if data is corrupted in transport.

It is meant for errors where length of something is wrong (and such
errors would likely be non-recoverable anyway)..



-Ilari