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From: "Thomas Bächler" <thomas@archlinux.org>
To: dm-crypt@saout.de
Subject: Re: [dm-crypt] Some questions about cryptsetup 1.6.x
Date: Wed, 12 Feb 2014 15:30:10 +0100	[thread overview]
Message-ID: <52FB8572.7030408@archlinux.org> (raw)
In-Reply-To: <20140212141908.GA9017@tansi.org>

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Am 12.02.2014 15:19, schrieb Arno Wagner:
> -h is the hash that the plain-text password is put through
> to turn it into a binary value of certain defined length.
> -c specifies the hash that goes into pbkdf2 for the hash
> iteration.

Are you sure?

I was under the impression that '-c' only affects the cipher parameter
passed to dm-crypt - a hash would then be relevant for cipher modes like
cbc-essiv, but xts-plain64 would ignore it. Thus, cryptsetup has default
like 'aes-cbc-essiv:sha256', since essiv needs a hash, and
aes-xts-plain64, since xts does not need a hash.

According to the manpage, -h is what is used in PBKDF2 in luksFormat
mode, or to hash the passphrase in plain mode.

To me, this makes much more sense than what you said.



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  reply	other threads:[~2014-02-12 14:30 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-02-12  9:49 [dm-crypt] Some questions about cryptsetup 1.6.x Cpp
2014-02-12 14:19 ` Arno Wagner
2014-02-12 14:30   ` Thomas Bächler [this message]
2014-02-12 15:59     ` Arno Wagner
2014-02-12 16:10     ` Milan Broz
2014-02-13  5:57       ` Arno Wagner
2014-02-12 15:04   ` Matthias Schniedermeyer
2014-02-12 15:57     ` Arno Wagner
2014-02-12 16:29       ` Matthias Schniedermeyer
2014-02-12 17:25         ` Arno Wagner
2014-02-12 16:20 ` Milan Broz

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