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From: Robert Nichols <rnicholsNOSPAM@comcast.net>
Date: Wed, 10 Dec 2014 16:34:59 -0600
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Subject: Re: [dm-crypt] How to derive master key in plain dm-crypt mode
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To: dm-crypt@saout.de

On 12/10/2014 05:48 AM, Jian-Ming Zheng wrote:
> In plain dm-crypt mode, there is no encrypted master key on the device
> (i.e., no metadata header). Is a master key derived from the user
> passphrase and used to en-/decrypt the device? If yes, how to derive
> the master key from the passphrase in plain mode?

The /cryptsetup/ manpage indicates that the key is just the hash of the
passphrase using the specified hash function and cropped to the required
key length. "cryptsetup --help" will show you the default hash function.

-- 
Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.