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[ Solved ] I can't change Disk Encryption password (infosec.pub)

submitted 6 months ago* (last edited 6 months ago) by [email protected] to c/[email protected]

11 comments fedilink hide all child comments

I tried the following

sudo cryptsetup luksChangekey /dev/nvme0n1p3 < new passphrase >

It then asks for the Sudo password, then asks for the old passphrase, but then it prints this error message

Failed to open key file.

what went wrong ?

Edit: turns out using GNOME Disks is way more straightforward.. 😅, thank you all

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[–] [email protected] 5 points 6 months ago

Refer to the cryptsetup-luksChangeKey man page --key-file options, you cannot change the password directly on a commandline; you either (a) type it interactively, (b) put it in a keyfile, or (c) accept input from STDIN with the standard use of - on the end (e.g. echo "mypass" | cryptsetup luksChangeKey /dev/sda - )

[–] [email protected] 4 points 6 months ago

The correct syntax is cryptsetup luksChangeKey <device> <key file>. So what you tried is opening a file that is named like your new passphrase. Such a file of course (hopefully) doesn't exist.

Just omit the last parameter, i.e. sudo cryptsetup luksChangekey /dev/nvme0n1p3 and enter the new password when it asks you to.

[–] [email protected] 2 points 6 months ago (1 children)

Have you tried using GNOME Disk Utility?

[–] [email protected] 1 points 6 months ago (2 children)

I have it installed, but I don't see the option 🤷‍♂️

[–] sloppy_diffuser 2 points 6 months ago

Try clicking on the encrypted partition to get the passphrase option.

https://askubuntu.com/questions/95137/how-to-change-luks-passphrase

[–] [email protected] 1 points 6 months ago (1 children)

Here's how to find it: https://spectra.video/w/tbLNakrf2ncii4NrqJbwE8

[–] [email protected] 2 points 6 months ago

OMG, thank youu.. It worked.. 🥳

[–] [email protected] 2 points 6 months ago (1 children)

What is the output if you run sudo cryptsetup --verbose open --test-passphrase /dev/nvme0n1p3?

[–] [email protected] 2 points 6 months ago (1 children)

It asks for the sudo password, then it prints

No usable token is available.

Then it asks : Enter passphrase for /dev/nvme0n1p3:

After entering my old passphrase it prints:

Key slot 0 unlocked
Command Successful.

[–] [email protected] 2 points 6 months ago (1 children)

Alright so no permission issue, what if you run the changekey command in a separate bash subprocess? sudo bash -c '($your-changekey-command-here)'

[–] [email protected] 2 points 6 months ago

Is it like the same first "cryptsetup luksChangekey..." But inside parentheses ? Im sure I'm getting the syntax wrong.. It prints

bash: line 1: -luksChangekey: command not found