[Cryptography] Photon beam splitters for "true" random number generation ?
patrick at rayservers.net
Thu Dec 24 10:47:24 EST 2015
Jerry Leichter wrote on 12/24/2015 06:09 AM:
>> patrick at laptop:~$ gpg --print-md sha256 scattered_leaves.jpg
>> scattered_leaves.jpg: 171E2552 72B2FB96 94BBB675 9B3203A1 ED799567
>> 1A808711 25E54D12 B106DCDA
>> # Then FWIW: patrick at laptop:~$ shred -u scattered_leaves.jpg
> In the interest of paranoid completeness: If your computer has an
> SSD rather than a traditional magnetic disk, shred won't actually
> destroy the data - its writes will simply go to new blocks on the
> SSD, and the old blocks will go onto an internal, inaccessible list
> for later cleaning and reuse. ...
Yes, it is a SSD, and thank you for the grim reminder of how everything
leaks like a sieve these days. It's yet another reason why it was a
good idea to encrypt the entire disk with dm-crypt.
Maybe to do a full cleanse I could run this until it exhausts the file
$ cat /dev/zero >giant
It has to put the zeros *somewhere*, after all.
> Perhaps you should have run gpg directly on the file from the SD card
> your camera wrote it to (assuming that's how you transferred it) and
> them destroyed the SD card; they're pretty cheap after all. -- Jerry
More information about the cryptography