Re: [dm-crypt] Option "validate passphrase" for command cryptsetup

[Milan Broz <gmazyland@gmail.com>]

On 06/19/2012 12:53 PM, Louis wrote:
> 	Hello,
> 	for information, I wrote a small C program to check if the given
> passphrase is correct, without doing anything on the disk. The command
> is used this way:

> 	If you think it can benefit cryptsetup, I offer to write the necessary
> patch to include it to cryptsetup (as a "luksValidateKey" LUKS action).

Special program or command is IMHO overkill, isn't enough just to add option
to cryptsetup luksOpen (--dry-run, --no-activate, whatever you prefer)?

So it will work just like

# cryptsetup luksOpen /dev/sdc anything --dry-run --verbose
Enter passphrase for /dev/sdc: 
No key available with this passphrase.
Enter passphrase for /dev/sdc: 
Key slot 0 unlocked.
Command successful.

Trivial to add to code... (while I am doing another RC today, it can be done
today even ;-)

Milan