Subject: Re: [PATCH 15/26] ubifs: Implement encrypt/decrypt for all IO
To: Michael Halcrow <mhalcrow@google.com>
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From: Richard Weinberger <richard@nod.at>
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Date: Fri, 21 Oct 2016 20:21:16 +0200
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On 21.10.2016 19:52, Michael Halcrow wrote:
> On Fri, Oct 21, 2016 at 07:21:04PM +0200, Richard Weinberger wrote:
>> On 21.10.2016 19:14, Michael Halcrow wrote:
>>> Compress-before-encrypt is a hazard.
>>>
>>> http://www.iacr.org/cryptodb/archive/2002/FSE/3091/3091.pdf
>>
>> I'm fully aware of that. But as usual it depends on the use case.
>> Compression is optional in UBIFS, paranoid users can disable it
>> when encryption is enabled.
> 
> It's not the paranoid users I'm concerned about.  It's those building
> systems with complexity and nuance on top of UBIFS who aren't paranoid
> enough.
> 
> I suggest disabling compression by default when encryption is enabled,
> unless the user explicitly enables both.

That's definitely an option, yes.

Thanks,
//richard