Pure Python Data Mangling or Encrypting

[Grant Edwards]

On 2015-06-24, Steven D'Aprano <steve at pearwood.info> wrote:
> On Wed, 24 Jun 2015 05:02 am, Randall Smith wrote:
>
>> Chunks of data (about 2MB) are to be stored on machines using a
>> peer-to-peer protocol.  The recipient of these chunks can't assume that
>> the payload is benign.  While the data senders are supposed to encrypt
>> data, that's not guaranteed, and I'd like to protect the recipient
>> against exposure to nefarious data by mangling or encrypting the data
>> before it is written to disk.
>
> I don't understand how mangling the data is supposed to protect the
> recipient. Don't they have the ability unmangle the data, and thus expose
> themselves to whatever nasties are in the files?

And how does writing unmangled data to disk expose anybody to
anything?  I've never heard of an exploit where writing an evilly
crafted bit-pattern to disk causes a any sort of problem.

-- 
Grant Edwards               grant.b.edwards        Yow! My mind is making
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