LUKS & search for passphrase using dictionary

Hi,

From time to time someone tries to recover (or crack) LUKS passphrase using dictionary lists.
I saw lately even some crazy patches for cryptsetup doing that.

Please do not patch source or create some slow bash scripts (initialization and memory locking cost resources). Just use libcryptsetup. I added some example how to do it, see

http://code.google.com/p/cryptsetup/source/browse/#git%2Fmisc%2Fdict_search

e.g. for JTR known password list you can run (on quadcore cpu here)

  # luks_dict test.img /usr/share/john/password.lst 4

Then read FAQ how LUKS keyslot iterations slow down these attacks...

It is just quickly written example, perhaps with some bugs.

Anyway, enjoy :)
Milan

p.s.
If you really run this, compile cryptsetup with openssl support (configure --with-crypto_backend=openssl) it is quicker than default gcrypt.

Urgh :-)

Cool! Nicely compact as any good piece of example code should be. I also like the multi-process capability.

Specifically, FAQ items 5.7, 5.8 and 5.9 can give you some insight about the amount of effort you can expect.

Arno Wagner,    Dr. sc. techn., Dipl. Inform.,   Email: [email protected] 
GnuPG:  ID: 1E25338F  FP: 0C30 5782 9D93 F785 E79C  0296 797F 6B50 1E25 338F
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