[dm-devel] Re: [lvm-devel] dm-crypt - some info, and a few development questions

[Christophe Saout]

Hi!

> Firstly I suggest you split this project into 2 chunks.  First
> concentrate on the device-mapper encryption target, and use dmsetup to
> do all of your testing. [...]

> The 2.4 version of dm has a very useful extra target method that
> allows you to catch the io when it has completed.  You should use this
> to perform decryption.  I have attached a patch that adds this
> functionality to 2.5, this has had limited testing, so it would be
> helpful if you could keep me informed of any successes/failures you
> have with it.
> [...]

> dm-devel at sistina.com is the right list for this discussion, or mail me
> directly if you want.

Would it be possible to do development of these things (especially the
dm part) to an open place? I'm very interested in the inner workings of
device-mapper and the new 2.5/2.6 kernel block io code.

If I had more time and would be able to understand these things better I
would have written some code by now (perhaps porting some of the missing
dm targets from 2.4 to 2.5 or so), but if I can see progress step by
step I'll perhaps be able to help. Or at least test it.

The latest kernels have a somewhat modified loop.c so that it supports
additional encryption again (cryptoloop.c), perhaps you can use some of
that code somehow.

And, I was just wondering, would it be theoretically possible to write a
dm target that stores data in a file, so that it replaces what the loop
device does? Or was dm not designed for this?

--
Christophe Saout <christophe at saout.de>
Please avoid sending me Word or PowerPoint attachments.
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