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Date: Wed, 18 Nov 2020 18:25:11 +0100
From: Davide Marchi <danjde@msw.it>
Message-ID: <8064bad388c679e803ef903e92cc6ca5@msw.it>
Subject: Re: [dm-crypt] Encrypting DVD or CDROM from iso
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To: dm-crypt@saout.de

Hi to All,
finally I've found the right (and tested) procedure in this simple 
script, made by sowbug: 
https://gist.github.com/sowbug/c7f83140581fbe3e6a9b3ddf24891e77#gistcomment-3531970


# All the code from 
http://billauer.co.il/blog/2010/10/encrypted-iso-dvd-luks-dm-crypt-fedora-linux/

MB_COUNT=100
VOL_NAME=MyVolName
DIR_TO_COPY=/tmp/mydir

# Make a 100MB disk image
dd if=/dev/zero of=disk.img bs=1M count=$MB_COUNT

# become root
sudo su

# write to the image
# ****** NOTE that you'll be prompted three times for a passphrase
losetup /dev/loop1 disk.img && \
   cryptsetup luksFormat /dev/loop1 && \
   cryptsetup luksOpen /dev/loop1 mybackupdisk && \
   genisoimage -R -J -joliet-long -graft-points -V $VOL_NAME -o 
/dev/mapper/mybackupdisk $DIR_TO_COPY

# close the device
cryptsetup luksClose /dev/mapper/mybackupdisk && \
   losetup -d /dev/loop1

# Now you have disk.img that can be burned to a CD/DVD, or just mount it 
in Linux.
# You'll be prompted for the passphrase each time you mount it.


Thanks

Davide
Italy