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Fix grub-install command

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Signed-off-by: Tommy <contact@tommytran.io>
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Tommy 2022-10-25 17:12:51 -04:00
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content/posts/linux/Desktop-Linux-Hardening.md
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@ -423,7 +423,7 @@ On systems which use [`grub-btrfs`](https://github.com/Antynea/grub-btrfs) to mi
- You should make `/boot` part of your root partition instead of a seperate one. In theory, if you have a seperate `/boot` partition, an evil maid attack can replace it with a malicious `/boot` partition and setup a fake `GRUB` decryption prompt for you to unlock the drive and subsequently compromising the rest of the system.
- You will need to install `GRUB` with the `--no-shim-lock` option. The full command I use on my Arch Linux system is
```bash
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=`GRUB` --modules="normal test efi_gop efi_uga search echo linux all_video gfxmenu gfxterm_background gfxterm_menu gfxterm loadenv configfile gzio part_gpt cryptodisk luks gcry_rijndael gcry_sha256 btrfs" --disable-shim-lock
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=GRUB --modules="normal test efi_gop efi_uga search echo linux all_video gfxmenu gfxterm_background gfxterm_menu gfxterm loadenv configfile gzio part_gpt cryptodisk luks gcry_rijndael gcry_sha256 btrfs tpm" --disable-shim-lock
```
- You will need to enroll your own key as described [above](#enrolling-your-own-keys), sign the kernel and `GRUB` with your own keys, removing shim and MOK from the boot chain (if you are using them), and finally setting up hooks to automate these tasks every update. On Arch-based distributions, you can find the instructions on setting up the hooks in the [Arch Wiki](https://wiki.archlinux.org/title/Unified_Extensible_Firmware_Interface/Secure_Boot#Signing_the_kernel_with_a_pacman_hook).
- You will need to disable the TPM module in your firmware to prevent `GRUB` from attempting to do [Measured Boot](https://www.gnu.org/software/grub/manual/grub/html_node/Measured-Boot.html), which does not work with `grub-btrfs`. The discussion for this issue can be found [here](https://github.com/Antynea/grub-btrfs/issues/156).