Enable Linux Secure Boot with TPM 2.0 (Manjaro / Archlinux) - rEFInd

90-mkinitcpio-install.hook.patch

--- /usr/share/libalpm/hooks/90-mkinitcpio-install.hook	2020-03-05 12:45:41.000000000 +0800
+++ /etc/pacman.d/hooks/90-mkinitcpio-install.hook	2020-06-13 23:08:32.861202141 +0800
@@ -8,5 +8,7 @@
 [Action]
 Description = Updating linux initcpios...
 When = PostTransaction
-Exec = /usr/share/libalpm/scripts/mkinitcpio-install
+Exec = /usr/local/share/libalpm/scripts/mkinitcpio-install
+Depends = sbsigntools
+Depends = x11-ssh-askpass
 NeedsTargets

README.md

Required

Hardware

• TPM module installed in the motherboard (that is set to TPM 2.0 mode from the BIOS).

Packages

• refind
• sbsigntools
• shim-signed
• tpm2-tss-engine
• tpm2-tools (optional)

Archlinux / Manjaro: pamac update --download-only --aur && pamac install refind sbsigntools shim-signed tpm2-tss-engine

Usage

sudo -i

# Patch refind-install script
curl -o- https://gist.githubusercontent.com/heri16/6df9ae37ae51496fe376debaca45540b/raw/refind-install.patch | patch /usr/bin/refind-install

# Install reFind EFI Bootloader to ESP partition (encrypted keys without TPM)
# refind-install --shim /usr/share/shim-signed/shimx64.efi --localkeys --encryptkeys --yes

# Install reFind EFI Bootloader to ESP partition (encrypted keys on TPM)
refind-install --shim /usr/share/shim-signed/shimx64.efi --localkeys --encryptkeys --engine tpm2tss --yes
efibootmgr

# Sign Linux kernel
sbsign --engine tpm2tss --key /etc/refind.d/keys/refind_local.key --cert /etc/refind.d/keys/refind_local.crt --output "/boot/vmlinuz-5.6-x86_64" "/boot/vmlinuz-5.6-x86_64"
sbverify --list "/boot/vmlinuz-5.6-x86_64"

# Sign Manjaro's Grub2 EFI Bootloader (optional)
sbsign --engine tpm2tss --key /etc/refind.d/keys/refind_local.key --cert /etc/refind.d/keys/refind_local.crt --output "/boot/efi/EFI/manjaro/grubx64.efi" "/boot/efi/EFI/manjaro/grubx64.efi"
sbverify --list "/boot/efi/EFI/manjaro/grubx64.efi"

# Reboot into BIOS

Then, reboot into BIOS to enable SecureBoot.

Once in MokManager add refind_local.cer to MoKList. refind_local.cer can be found inside a directory called keys in the rEFInd's installation directory, e.g. esp/EFI/refind/keys/refind_local.cer.

Misc

Enable pacman hook

Make pacman sign the kernel automatically on kernel updates.

sudo -i
pamac install x11-ssh-askpass
curl -o- https://gist.githubusercontent.com/heri16/6df9ae37ae51496fe376debaca45540b/raw/90-mkinitcpio-install.hook.patch | patch -o "/etc/pacman.d/hooks/90-mkinitcpio-install.hook" /usr/share/libalpm/hooks/90-mkinitcpio-install.hook
curl -o- https://gist.githubusercontent.com/heri16/6df9ae37ae51496fe376debaca45540b/raw/mkinitcpio-install.patch | patch -o "/usr/local/share/libalpm/scripts/mkinitcpio-install" /usr/share/libalpm/scripts/mkinitcpio-install

Useful Info

• https://wiki.archlinux.org/index.php/REFInd#Using_shim
• https://wiki.archlinux.org/index.php/Unified_Extensible_Firmware_Interface/Secure_Boot#Signing_the_kernel_and_boot_manager
• https://superuser.com/questions/1557668/undo-sbsign-on-executable-remove-an-attached-image-signature
• https://github.com/tpm2-software/tpm2-tss-engine

mkinitcpio-install.patch

--- /usr/share/libalpm/scripts/mkinitcpio-install	2020-03-05 12:45:41.000000000 +0800
+++ /usr/local/share/libalpm/scripts/mkinitcpio-install	2020-06-20 06:09:53.900484682 +0800
@@ -39,8 +39,20 @@
         fi
     fi
 
-    # always install the kernel
-    install -Dm644 "${line}" "/boot/vmlinuz-${kernelbase}"
+    if [[ $DISPLAY ]]; then
+        # always sign & install the kernel for SecureBoot
+        KeyPassphrase=$(/usr/lib/ssh/ssh-askpass "Please enter your SecureBoot Key passphrase:")
+        SbSignCommand=$(printf "%q " /usr/bin/sbsign --engine tpm2tss --key /etc/refind.d/keys/refind_local.key --cert /etc/refind.d/keys/refind_local.crt --output "/boot/vmlinuz-${kernelbase}" "${line}")
+        echo "$KeyPassphrase" |
+            script -qefc "$SbSignCommand" --force /dev/null 2>&1 | ( \
+                head -n 2 >/dev/null # Skip the first two lines (incl. passphrase).
+                grep -v "data remaining.*gaps between PE/COFF sections"
+            )
+        /usr/bin/sbverify --list "/boot/vmlinuz-${kernelbase}"
+    else
+        # always install the kernel
+        install -Dm644 "${line}" "/boot/vmlinuz-${kernelbase}"
+    fi
 
     # compound args for each kernel
     args+=(-p "${pkgbase}")

objcopy.sh

#!/bin/sh
VERSION=5.7

cd /boot/efi/EFI/Linux
cat /boot/amd-ucode.img /boot/initramfs-${VERSION}-x86_64.img > initrd.img
objcopy \
    --add-section .osrel="/usr/lib/os-release" --change-section-vma .osrel=0x20000 \
    --add-section .cmdline="kernel-command-line.txt" --change-section-vma .cmdline=0x30000 \
    --add-section .splash="/usr/share/systemd/bootctl/splash-manjaro.bmp" --change-section-vma .splash=0x40000 \
    --add-section .linux="/boot/vmlinuz-${VERSION}-x86_64" --change-section-vma .linux=0x2000000 \
    --add-section .initrd="initrd.img" --change-section-vma .initrd=0x3000000 \
    "/usr/lib/systemd/boot/efi/linuxx64.efi.stub" "linux${VERSION//.}.efi"
sbsign --engine tpm2tss --key /etc/refind.d/keys/refind_local.key --cert /etc/refind.d/keys/refind_local.crt --output "linux${VERSION//.}.efi" "linux${VERSION//.}.efi"
sbverify --list "linux${VERSION//.}.efi"
rm initrd.img

refind-install.patch

--- /usr/bin/refind-install	2020-04-23 14:10:32.000000000 +0800
+++ ./refind-install	2020-06-12 13:48:27.371630998 +0800
@@ -23,6 +23,7 @@
 #           only under Linux.
 #    "--preloader" is synonymous with "--shim". Valid only under Linux.
 #    "--encryptkeys" password-protects the Secure Boot private key.
+#    "--engine" engine that protects the Secure Boot private key.
 #    "--localkeys" to re-sign x86-64 binaries with a locally-generated key.
 #           Valid only under Linux.
 #    "--keepname" to keep refind_x64.efi name as such even when using shim.
@@ -156,6 +157,9 @@
               ;;
          --encryptkeys) EncryptKeys=1
               ;;
+         --engine) Engine="$2"
+              shift
+              ;;
          --shim | --preloader) ShimSource="$2"
               ShimType=`basename $ShimSource`
               shift
@@ -171,7 +175,7 @@
          * ) echo "Usage: $0 [--notesp | --usedefault {device-file} | --root {dir} |"
              echo "                     --ownhfs {device-file} ] [--keepname]"
              echo "                  [--nodrivers | --alldrivers] [--shim {shimfile}]"
-             echo "                  [--localkeys [--encryptkeys]] [--keepname] [--yes]"
+             echo "                  [--localkeys [--encryptkeys] [--engine {engine}]] [--keepname] [--yes]"
              exit 1
       esac
       shift
@@ -216,6 +220,10 @@
       echo "The --encryptkeys option requires the use of --localkeys! Aborting!"
       exit 1
    fi
+   if [[ $Engine && "$LocalKeys" == 0 ]] ; then
+      echo "The --engine option requires the use of --localkeys! Aborting!"
+      exit 1
+   fi
    RLConfFile="$RootDir/boot/refind_linux.conf"
    EtcKeysDir="$RootDir/etc/refind.d/keys"
 } # GetParams()
@@ -1079,12 +1087,44 @@
          cp -f "$DerKey" "$DerKey.backup" 2> /dev/null
       fi
       if [[ $EncryptKeys == 1 ]]; then
+         ReadKeyPassphrase
          KeyEncryptionArgument=""
       else
          KeyEncryptionArgument="-nodes"
       fi
-      "$OpenSSL" req -new -x509 -newkey rsa:2048 -keyout "$PrivateKey" -out "$CertKey" \
+      if [[ ! $Engine ]]; then
+         if [[ $EncryptKeys == 1 ]]; then
+            echo "$KeyPassphrase" |
+               "$OpenSSL" req -new -x509 -newkey rsa:2048 -keyout "$PrivateKey" -out "$CertKey" \
+                     $KeyEncryptionArgument -days 3650 -subj "/CN=Locally-generated rEFInd key/" -passout stdin
+            echo -e "$KeyPassphrase\n$KeyPassphrase" |
+               "$OpenSSL" pkcs8 -topk8 -iter 1000000 -in "$PrivateKey" -out "${PrivateKey}~" -passin stdin -passout stdin
+            mv "${PrivateKey}~" "$PrivateKey"
+         else
+            "$OpenSSL" req -new -x509 -newkey rsa:2048 -keyout "$PrivateKey" -out "$CertKey" \
                      $KeyEncryptionArgument -days 3650 -subj "/CN=Locally-generated rEFInd key/"
+         fi
+      else
+         EngineName=$("$OpenSSL" engine "$Engine" | cut -d ' ' -f 2)
+         if [[ "$Engine" == "tpm2tss" ]]; then
+            if [[ $EncryptKeys == 1 ]]; then
+               tpm2tss-genkey -a rsa -p "$KeyPassphrase" "$PrivateKey"
+            else
+               tpm2tss-genkey -a rsa "$PrivateKey"
+            fi
+            KeyReqArguments=(-engine "$Engine" -keyform engine -key "$PrivateKey")
+         else
+            KeyReqArguments=(-keygen_engine "$Engine" -newkey rsa:2048 -keyout "$PrivateKey")
+         fi
+         if [[ $EncryptKeys == 1 ]]; then
+            echo "$KeyPassphrase" |
+               "$OpenSSL" req -new -x509 ${KeyReqArguments[@]} -out "$CertKey" \
+                     $KeyEncryptionArgument -days 3650 -subj "/CN=${EngineName}-generated rEFInd key/" -passin stdin
+         else
+            "$OpenSSL" req -new -x509 ${KeyReqArguments[@]} -out "$CertKey" \
+                     $KeyEncryptionArgument -days 3650 -subj "/CN=${EngineName}-generated rEFInd key/"
+         fi
+      fi
       "$OpenSSL" x509 -in "$CertKey" -out "$DerKey" -outform DER
       chmod 0600 "$PrivateKey"
    else
@@ -1100,16 +1140,25 @@
 SignOneBinary() {
    ReadKeyPassphrase --no-confirm
    if [[ "$EncryptKeys" == 1 ]] ; then
-      SbSignCommand=$(printf "%q " "$SBSign" --key "$PrivateKey" --cert "$CertKey" --output "$2" "$1")
+      if [[ ! $Engine ]]; then
+         SbSignCommand=$(printf "%q " "$SBSign" --key "$PrivateKey" --cert "$CertKey" --output "$2" "$1")
+      else
+         SbSignCommand=$(printf "%q " "$SBSign" --engine "$Engine" --key "$PrivateKey" --cert "$CertKey" --output "$2" "$1")
+      fi
       echo "$KeyPassphrase" |
          script -qefc "$SbSignCommand" --force /dev/null 2>&1 | ( \
               head -n 2 >/dev/null # Skip the first two lines (incl. passphrase).
               grep -v "data remaining.*gaps between PE/COFF sections"
             )
-       local status="${PIPESTATUS[1]}"
+      local status="${PIPESTATUS[1]}"
    else
-      "$SBSign" --key "$PrivateKey" --cert "$CertKey" --output "$2" "$1" 2>&1 >/dev/null | \
+      if [[ ! $Engine ]]; then
+         "$SBSign" --key "$PrivateKey" --cert "$CertKey" --output "$2" "$1" 2>&1 >/dev/null | \
+                grep -v "data remaining.*gaps between PE/COFF sections"
+      else
+         "$SBSign" --engine "$Engine" --key "$PrivateKey" --cert "$CertKey" --output "$2" "$1" 2>&1 >/dev/null | \
                 grep -v "data remaining.*gaps between PE/COFF sections"
+      fi
       local status="${PIPESTATUS[0]}"
    fi
    if [[ "$status" != 0 ]] ; then

Required

Hardware

• TPM module installed in the motherboard (that is set to TPM 2.0 mode from the BIOS).

Packages

• refind
• sbsigntools
• shim-signed
• tpm2-tss-engine
• tpm2-tools (optional)

Archlinux / Manjaro: pamac update --download-only --aur && pamac install refind sbsigntools shim-signed tpm2-tss-engine

Usage

sudo -i

# Patch refind-install script
curl -o- https://gist.githubusercontent.com/heri16/6df9ae37ae51496fe376debaca45540b/raw/refind-install.patch | patch /usr/bin/refind-install

# Install reFind EFI Bootloader to ESP partition (encrypted keys without TPM)
# refind-install --shim /usr/share/shim-signed/shimx64.efi --localkeys --encryptkeys --yes

# Install reFind EFI Bootloader to ESP partition (encrypted keys on TPM)
refind-install --shim /usr/share/shim-signed/shimx64.efi --localkeys --encryptkeys --engine tpm2tss --yes
efibootmgr

# Sign Linux kernel
sbsign --engine tpm2tss --key /etc/refind.d/keys/refind_local.key --cert /etc/refind.d/keys/refind_local.crt --output "/boot/vmlinuz-5.6-x86_64" "/boot/vmlinuz-5.6-x86_64"
sbverify --list "/boot/vmlinuz-5.6-x86_64"

# Sign Manjaro's Grub2 EFI Bootloader (optional)
sbsign --engine tpm2tss --key /etc/refind.d/keys/refind_local.key --cert /etc/refind.d/keys/refind_local.crt --output "/boot/efi/EFI/manjaro/grubx64.efi" "/boot/efi/EFI/manjaro/grubx64.efi"
sbverify --list "/boot/efi/EFI/manjaro/grubx64.efi"

# Reboot into BIOS

Then, reboot into BIOS to enable SecureBoot.

Once in MokManager add refind_local.cer to MoKList. refind_local.cer can be found inside a directory called keys in the rEFInd's installation directory, e.g. esp/EFI/refind/keys/refind_local.cer.

Misc

Enable pacman hook

Make pacman sign the kernel automatically on kernel updates.

sudo -i
pamac install x11-ssh-askpass
curl -o- https://gist.githubusercontent.com/heri16/6df9ae37ae51496fe376debaca45540b/raw/90-mkinitcpio-install.hook.patch | patch -o "/etc/pacman.d/hooks/90-mkinitcpio-install.hook" /usr/share/libalpm/hooks/90-mkinitcpio-install.hook
curl -o- https://gist.githubusercontent.com/heri16/6df9ae37ae51496fe376debaca45540b/raw/mkinitcpio-install.patch | patch -o "/usr/local/share/libalpm/scripts/mkinitcpio-install" /usr/share/libalpm/scripts/mkinitcpio-install

Useful Info

• https://wiki.archlinux.org/index.php/REFInd#Using_shim
• https://wiki.archlinux.org/index.php/Unified_Extensible_Firmware_Interface/Secure_Boot#Signing_the_kernel_and_boot_manager
• https://superuser.com/questions/1557668/undo-sbsign-on-executable-remove-an-attached-image-signature
• https://github.com/tpm2-software/tpm2-tss-engine