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So, I've installed Manjaro quite while ago, and I let secure boot disabled during installation. Dang! Is there a way to keep (most of) my system and enable secure boot and LUKS after the fact?

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[–] [email protected] 5 points 11 months ago* (last edited 11 months ago) (2 children)

It depends on a single variable - does your motherboard support manipulating the secure boot keys? I've only done it on prebuilt dells and dell laptops, but some other manufacturers also allow it.

The procedure is very simple, but has many steps. Don't get discouraged! I remember ArchWiki having a very thorough guide that worked for me.

The gist of it is you provide UEFI firmware the cert to trust and then use the keys to sign your kernel image. I've never had to deal with signing the modules (mostly nVidia related, I think), but the procedure would be the same.

[–] [email protected] 5 points 11 months ago (1 children)

I had it scripted at some point - this is the file

  • Line 6 creates the UKI
  • Line 9 signs it
  • Line 12 changes the boot order.

Good luck!

[–] [email protected] 2 points 11 months ago (1 children)
[–] [email protected] 3 points 11 months ago (1 children)

My bad, private repo. Here's the content:

#!/bin/zsh

# 2022.09.26

# Generate
dracut --quiet --zstd --kver 6.0.2-gentoo --filesystems btrfs --early-microcode --uefi --uefi-splash-image $HOME/Nextcloud/Pictures/gentoo.full.height.nvme.bmp --uefi-stub /usr/lib/systemd/boot/efi/linuxx64.efi.stub --no-machineid --stdlog 4 --force --kernel-cmdline "rd.luks=1 rd.lvm=0 rd.md=0 rd.dm=0 rd.fstab=1 root=UUID=f5f8d75d-8aa8-4cea-83f9-3489a92a23e0 rd.luks.key=/luks.key:UUID=8E55-4050 rd.luks.uuid=5f5ab8ff-f1ea-4c09-960a-73f9bf5b7698 rootflags=noatime,discard=async,subvol=@snapshots/root/2022-10-18_102847 rootfstype=btrfs quiet delayacct i915.enable_guc=3"

# Sign
sbsign --key secure-boot/db.key --cert secure-boot/db.crt --output /boot/EFI/Linux/linux-6.0.2-gentoo.signed.efi /boot/EFI/Linux/linux-6.0.2-gentoo.efi

# Change boot order
efibootmgr --create --disk /dev/sdb --loader EFI/Linux/linux-6.0.2-gentoo.signed.efi --label Gentoo-6.0.2-signed --part 3 --verbose

[–] [email protected] 2 points 11 months ago

I have since replaced the hardcoded values with variables, but evidently haven't pushed the changes to gitlab. Having said that - not having variables might make it easier to understand in this case.

[–] [email protected] 4 points 11 months ago (1 children)

I think, I can install keys in my AMI bios. So, basically, I'd create some keys, sign the kernel with it, reboot, install them keys in UEFI, enable secure boot, and, fingers crossed, I'd boot?

[–] [email protected] 1 points 11 months ago

You might have to enable Audit mode or similar - again, depends on the manufacturer - to generate the keys. But yes, essentially that's the gist of it.

[–] breadsmasher 2 points 11 months ago* (last edited 11 months ago) (2 children)

~~iirc Secure Boot requires the kernel to be signed with some payment given to (I think) Microsoft to do it. I believe Canonical / Ubuntu are one of the few to do this~~.

~~So no, Manjaro as far I am currently aware, doesn’t support secure boot (or secure boot doesn’t support Manjaro)~~

See this comment https://sh.itjust.works/comment/1796724

[–] [email protected] 5 points 11 months ago (1 children)

You can, and for Linux generally have to, manage your own secure boot keys and signing your own kernal, united, modules, etc. Conacal and Red Hat have signing keys iirc, but distributions can and do get the shim boot loader signed so secure boot works. The arch wiki has a page on how to setup secure boot . Many distros installers do end up signed as well so you can go through the full install process with secure boot enabled.

[–] breadsmasher 1 points 11 months ago (1 children)

Nice one, my comment is old news then!

[–] [email protected] 1 points 11 months ago* (last edited 11 months ago)

eh, its true if you want it to be signed by microsoft, which some projects have forked out for, buut it was put into the spec for x86_64 systems that users can replace the keys. so you can make your own keys, and if you want to dual boot add microsoft's keys to the ok to boot list.

one of the signed projects is a shim that lets you approve whatever you want more or less; pretty much everything that talks about MOK refers back to this shim. many distributions use this shim

[–] [email protected] 2 points 11 months ago

Fedora also has this I think.

[–] HR_Pufnstuf 0 points 11 months ago

Why would you want it on?