gbde blackening feature - how are the keys "destroyed"?

[David Kreil]

Hello,

I was wondering whether someone knowledgable about gbde internals could tell 
me how the keys are being destroyed on request under the "blackening feature". 
Ideally, I'd like them to be overwritten with random data at least 20 times 
independently, but I suspect it may well be done in a different way. I'd be 
grateful for learning how the blackening works (and why!).

With many thanks for your help in advance,

David Kreil.



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Dr David Philip Kreil                 ("`-''-/").___..--''"`-._
Research Fellow                        `6_ 6  )   `-.  (     ).`-.__.`)
University of Cambridge                (_Y_.)'  ._   )  `._ `. ``-..-'
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