chore(docs): add ubuntu secure boot setup guide

README.md

@@ -37,6 +37,7 @@ simplify installation and usage.
 
 ## Documentation
 
+- [Ubuntu Secure Boot Setup Guide]
 - [Fedora Setup Guide]
 - [Generic Linux Setup Guide]
 - [Alpine Edge Setup Guide]
@@ -61,12 +62,12 @@ simplify installation and usage.
 - [x] Load Linux initrd from disk
 - [x] Basic boot menu
 - [x] BLS autoconfiguration support
-- [x] [Secure Boot support](https://github.com/edera-dev/sprout/issues/20): partial
+- [x] [Secure Boot support](https://github.com/edera-dev/sprout/issues/20): beta
+- [x] [Bootloader interface support](https://github.com/edera-dev/sprout/issues/21): beta
+- [x] [BLS specification conformance](https://github.com/edera-dev/sprout/issues/2): beta
 
 ### Roadmap
 
-- [ ] [Bootloader interface support](https://github.com/edera-dev/sprout/issues/21)
-- [ ] [BLS specification conformance](https://github.com/edera-dev/sprout/issues/2)
 - [ ] [Full-featured boot menu](https://github.com/edera-dev/sprout/issues/1)
 - [ ] [UKI support](https://github.com/edera-dev/sprout/issues/6): partial
 - [ ] [multiboot2 support](https://github.com/edera-dev/sprout/issues/7)
@@ -147,6 +148,7 @@ autoconfigure = true
 ```
 
 [Edera]: https://edera.dev
+[Ubuntu Secure Boot Setup Guide]: ./docs/ubuntu-secure-boot-setup.md
 [Fedora Setup Guide]: ./docs/fedora-setup.md
 [Generic Linux Setup Guide]: ./docs/generic-linux-setup.md
 [Alpine Edge Setup Guide]: ./docs/alpine-edge-setup.md

docs/ubuntu-secure-boot-setup.md

@@ -0,0 +1,126 @@
+# Ubuntu Secure Boot Setup
+
+## Generate and Install Secure Boot Key
+
+```bash
+# Create a directory to store the Secure Boot MOK key and certificates.
+mkdir -p /etc/sprout/secure-boot
+# Change to the created directory.
+cd /etc/sprout/secure-boot
+# Generate a MOK key and certificate.
+$ openssl req \
+  -newkey rsa:4096 -nodes -keyout mok.key \
+  -new -x509 -sha256 -days 3650 -subj '/CN=Sprout Secure Boot/' \
+  -out mok.crt
+# Generate a DER encoded certificate for enrollment.
+$ openssl x509 -outform DER -in mok.crt -out mok.cer
+# Import the certificate into the Secure Boot environment.
+# This will ask you to make a password that will be used during enrollment.
+$ mokutil --import mok.cer
+# Reboot your machine.
+# During boot, MOK enrollment should appear. If it doesn't, ensure you are booting into the shim.
+# Press any key to begin MOK management. Select "Enroll MOK".
+# Select "View key 0", and ensure the subject says "CN=Sprout Secure Boot".
+# If the subject does not match, something has gone wrong with MOK enrollment.
+# Press Enter to continue, then select the "Continue" option.
+# When it asks to enroll the key, select the "Yes" option.
+# Enter the password that you created during the mokutil --import step.
+# Select "Reboot" to boot back into your Operating System.
+```
+
+## Prepare Secure Boot Environment
+
+```bash
+# Create a directory for Sprout EFI artifacts.
+$ mkdir -p /boot/efi/EFI/sprout
+
+# For x86_64, copy the following artifacts to the Sprout EFI directory.
+$ cp /usr/lib/shim/shimx64.efi.signed /boot/efi/EFI/sprout/shimx64.efi
+$ cp /usr/lib/shim/mmx64.efi /boot/efi/EFI/sprout/mmx64.efi
+$ cp /usr/lib/shim/fbx64.efi /boot/efi/EFI/sprout/fbx64.efi
+
+# For aarch64, copy the following artifacts to the Sprout EFI directory.
+$ cp /usr/lib/shim/shimaa64.efi.signed /boot/efi/EFI/sprout/shimaa64.efi
+$ cp /usr/lib/shim/mmaa64.efi /boot/efi/EFI/sprout/mmaa64.efi
+$ cp /usr/lib/shim/fbaa64.efi /boot/efi/EFI/sprout/fbaa64.efi
+```
+
+## Install Unsigned Sprout
+
+Download the latest sprout.efi release from the [GitHub releases page](https://github.com/edera-dev/sprout/releases).
+For x86_64 systems, download the `sprout-x86_64.efi` file, and for ARM64 systems, download the `sprout-aarch64.efi` file.
+Copy the downloaded `sprout.efi` file to `/boot/efi/EFI/sprout/sprout.unsigned.efi` on your EFI System Partition.
+
+## Sign Sprout for Secure Boot
+
+```bash
+# For x86_64, sign the unsigned Sprout artifact and name it grubaa64.efi which is what the shim will call.
+$ sbsign \
+    --key /etc/sprout/secure-boot/mok.key \
+    --cert /etc/sprout/secure-boot/mok.crt \
+    --output /boot/efi/EFI/sprout/grubx64.efi \
+    /boot/efi/EFI/sprout/sprout.unsigned.efi
+
+# For aarch64, sign the unsigned Sprout artifact and name it grubaa64.efi which is what the shim will call.
+$ sbsign \
+    --key /etc/sprout/secure-boot/mok.key \
+    --cert /etc/sprout/secure-boot/mok.crt \
+    --output /boot/efi/EFI/sprout/grubaa64.efi \
+    /boot/efi/EFI/sprout/sprout.unsigned.efi
+```
+
+## Sign EFI Drivers
+
+If you have an EFI driver, copy the driver to `/boot/efi/EFI/sprout/DRIVER_NAME.unsigned.efi` for signing.
+
+For example, the `ext4` driver, copy the `ext4.efi` file to `/boot/efi/EFI/sprout/ext4.unsigned.efi`.
+
+Then sign the driver with the Sprout Secure Boot key:
+
+```bash
+# Sign the ext4 driver at ext4.unsigned.efi, placing it at ext4.efi, which will be used in the configuration.
+$ sbsign \
+    --key /etc/sprout/secure-boot/mok.key \
+    --cert /etc/sprout/secure-boot/mok.crt \
+    --output /boot/efi/EFI/sprout/ext4.efi \
+    /boot/efi/EFI/sprout/ext4.unsigned.efi
+```
+
+## Create Sprout Configuration
+
+Write the following to the file `/boot/efi/sprout.toml`:
+
+```toml
+# sprout configuration: version 1
+version = 1
+
+# global values.
+[values]
+# your linux kernel command line.
+linux-options = "root=UUID=MY_ROOT_UUID"
+
+# load an ext4 EFI driver.
+[drivers.ext4]
+path = "\\EFI\\sprout\\ext4.efi"
+
+# global options.
+[options]
+# enable autoconfiguration by detecting bls enabled
+# filesystems and generating boot entries for them.
+autoconfigure = true
+```
+
+Ensure you add the signed driver paths to the configuration, not the unsigned ones.
+If you do not have any drivers, exclude the drivers section entirely.
+
+## Configure Sprout Boot Entry
+
+```bash
+# In the following commands, replace /dev/ESP_PARTITION with the actual path to the ESP partition block device.
+
+# For x86_64, run this command to add Sprout as the default boot entry.
+$ efibootmgr -d /dev/ESP_PARTITION -c -L 'Sprout' -l '\EFI\sprout\shimx64.efi'
+
+# For aarch64, run this command to add Sprout as the default boot entry.
+$ efibootmgr -d /dev/ESP_PARTITION -c -L 'Sprout' -l '\EFI\sprout\shimaa64.efi'
+```