From fc08510f22d266677a98afae4932f5ea3bee1666 Mon Sep 17 00:00:00 2001 From: Javier Tia Date: Thu, 3 Oct 2024 15:33:29 -0600 Subject: [PATCH] arm: Enable Secure Boot in all required recipes In the target, Secure Boot starts from the firmware (u-boot), adds the signing keys, and verifies the bootloader (systemd-boot) and kernel (Linux). sbsign bbclass is used to sign the binaries. sbsign is the name of the tool used to sign these binaries. Hence the name of this class to sbsign and variables with SBSIGN prefix. Signed-off-by: Javier Tia Signed-off-by: Jon Mason --- meta-arm/classes/sbsign.bbclass | 31 +++++++++++++++++++ .../u-boot/u-boot-uefi-secureboot.inc | 17 ++++++++++ .../u-boot/u-boot/uefi-secureboot.cfg | 10 ++++++ meta-arm/recipes-bsp/u-boot/u-boot_%.bbappend | 2 ++ .../systemd/systemd-boot-uefi-secureboot.inc | 7 +++++ .../systemd/systemd-boot_%.bbappend | 1 + meta-arm/recipes-core/systemd/systemd-efi.inc | 1 + .../recipes-core/systemd/systemd_%.bbappend | 1 + .../linux/linux-yocto%.bbappend | 2 ++ .../linux/linux-yocto-uefi-secureboot.inc | 14 +++++++++ 10 files changed, 86 insertions(+) create mode 100644 meta-arm/classes/sbsign.bbclass create mode 100644 meta-arm/recipes-bsp/u-boot/u-boot-uefi-secureboot.inc create mode 100644 meta-arm/recipes-bsp/u-boot/u-boot/uefi-secureboot.cfg create mode 100644 meta-arm/recipes-core/systemd/systemd-boot-uefi-secureboot.inc create mode 100644 meta-arm/recipes-core/systemd/systemd-boot_%.bbappend create mode 100644 meta-arm/recipes-core/systemd/systemd-efi.inc create mode 100644 meta-arm/recipes-core/systemd/systemd_%.bbappend create mode 100644 meta-arm/recipes-kernel/linux/linux-yocto-uefi-secureboot.inc diff --git a/meta-arm/classes/sbsign.bbclass b/meta-arm/classes/sbsign.bbclass new file mode 100644 index 00000000..551b951d --- /dev/null +++ b/meta-arm/classes/sbsign.bbclass @@ -0,0 +1,31 @@ +# Sign binaries for UEFI Secure Boot +# +# Usage in recipes: +# +# Set binary to sign per recipe: +# SBSIGN_TARGET_BINARY = "${B}/binary_to_sign" +# +# Then call do_sbsign() in correct stage of the build +# do_compile:append() { +# do_sbsign +# } + +DEPENDS += 'gen-sbkeys' +DEPENDS += "sbsigntool-native" + +SBSIGN_KEY = "${SBSIGN_KEYS_DIR}/db.key" +SBSIGN_CERT = "${SBSIGN_KEYS_DIR}/db.crt" +SBSIGN_TARGET_BINARY ?= "binary_to_sign" + +# Not adding as task since recipes may need to sign binaries at different +# stages. Instead they can call this function when needed by calling this function +do_sbsign() { + bbnote "Signing ${PN} binary ${SBSIGN_TARGET_BINARY} with ${SBSIGN_KEY} and ${SBSIGN_CERT}" + ${STAGING_BINDIR_NATIVE}/sbsign \ + --key "${SBSIGN_KEY}" \ + --cert "${SBSIGN_CERT}" \ + --output "${SBSIGN_TARGET_BINARY}.signed" \ + "${SBSIGN_TARGET_BINARY}" + cp "${SBSIGN_TARGET_BINARY}" "${SBSIGN_TARGET_BINARY}.unsigned" + cp "${SBSIGN_TARGET_BINARY}.signed" "${SBSIGN_TARGET_BINARY}" +} diff --git a/meta-arm/recipes-bsp/u-boot/u-boot-uefi-secureboot.inc b/meta-arm/recipes-bsp/u-boot/u-boot-uefi-secureboot.inc new file mode 100644 index 00000000..e58035a9 --- /dev/null +++ b/meta-arm/recipes-bsp/u-boot/u-boot-uefi-secureboot.inc @@ -0,0 +1,17 @@ +FILESEXTRAPATHS:prepend := "${THISDIR}/${PN}:" + +SRC_URI += "file://uefi-secureboot.cfg" + +inherit sbsign + +DEPENDS += 'python3-pyopenssl-native' + +do_compile:prepend() { + export CRYPTOGRAPHY_OPENSSL_NO_LEGACY=1 + + "${S}"/tools/efivar.py set -i "${S}"/ubootefi.var -n pk -d "${SBSIGN_KEYS_DIR}"/PK.esl -t file + "${S}"/tools/efivar.py set -i "${S}"/ubootefi.var -n kek -d "${SBSIGN_KEYS_DIR}"/KEK.esl -t file + "${S}"/tools/efivar.py set -i "${S}"/ubootefi.var -n db -d "${SBSIGN_KEYS_DIR}"/db.esl -t file + "${S}"/tools/efivar.py set -i "${S}"/ubootefi.var -n dbx -d "${SBSIGN_KEYS_DIR}"/dbx.esl -t file + "${S}"/tools/efivar.py print -i "${S}"/ubootefi.var +} diff --git a/meta-arm/recipes-bsp/u-boot/u-boot/uefi-secureboot.cfg b/meta-arm/recipes-bsp/u-boot/u-boot/uefi-secureboot.cfg new file mode 100644 index 00000000..acdcfddd --- /dev/null +++ b/meta-arm/recipes-bsp/u-boot/u-boot/uefi-secureboot.cfg @@ -0,0 +1,10 @@ +CONFIG_CMD_BOOTMENU=y +CONFIG_USE_BOOTCOMMAND=y +CONFIG_BOOTCOMMAND="bootmenu" +CONFIG_USE_PREBOOT=y +CONFIG_EFI_VAR_BUF_SIZE=65536 +CONFIG_FIT_SIGNATURE=y +CONFIG_EFI_SECURE_BOOT=y +CONFIG_EFI_VARIABLES_PRESEED=y +CONFIG_PREBOOT="setenv bootmenu_0 UEFI Boot Manager=bootefi bootmgr; setenv bootmenu_1 UEFI Maintenance Menu=eficonfig" +CONFIG_PREBOOT_DEFINED=y diff --git a/meta-arm/recipes-bsp/u-boot/u-boot_%.bbappend b/meta-arm/recipes-bsp/u-boot/u-boot_%.bbappend index 0683a783..8542ccfc 100644 --- a/meta-arm/recipes-bsp/u-boot/u-boot_%.bbappend +++ b/meta-arm/recipes-bsp/u-boot/u-boot_%.bbappend @@ -2,3 +2,5 @@ FILESEXTRAPATHS:prepend := "${THISDIR}/${PN}:" SRC_URI:append:qemuarm64-secureboot = " file://qemuarm64.cfg" SRC_URI:append:qemuarm-secureboot = " file://qemuarm.cfg" + +require ${@bb.utils.contains('MACHINE_FEATURES', 'uefi-secureboot', 'u-boot-uefi-secureboot.inc', '', d)} diff --git a/meta-arm/recipes-core/systemd/systemd-boot-uefi-secureboot.inc b/meta-arm/recipes-core/systemd/systemd-boot-uefi-secureboot.inc new file mode 100644 index 00000000..84196a68 --- /dev/null +++ b/meta-arm/recipes-core/systemd/systemd-boot-uefi-secureboot.inc @@ -0,0 +1,7 @@ +inherit sbsign + +SBSIGN_TARGET_BINARY = "${B}/src/boot/efi/systemd-boot${EFI_ARCH}.efi" + +do_compile:append() { + do_sbsign +} diff --git a/meta-arm/recipes-core/systemd/systemd-boot_%.bbappend b/meta-arm/recipes-core/systemd/systemd-boot_%.bbappend new file mode 100644 index 00000000..9850bbf9 --- /dev/null +++ b/meta-arm/recipes-core/systemd/systemd-boot_%.bbappend @@ -0,0 +1 @@ +require ${@bb.utils.contains('MACHINE_FEATURES', 'uefi-secureboot', 'systemd-boot-uefi-secureboot.inc', '', d)} diff --git a/meta-arm/recipes-core/systemd/systemd-efi.inc b/meta-arm/recipes-core/systemd/systemd-efi.inc new file mode 100644 index 00000000..5572e51a --- /dev/null +++ b/meta-arm/recipes-core/systemd/systemd-efi.inc @@ -0,0 +1 @@ +PACKAGECONFIG:append = " efi" diff --git a/meta-arm/recipes-core/systemd/systemd_%.bbappend b/meta-arm/recipes-core/systemd/systemd_%.bbappend new file mode 100644 index 00000000..660358c2 --- /dev/null +++ b/meta-arm/recipes-core/systemd/systemd_%.bbappend @@ -0,0 +1 @@ +require ${@bb.utils.contains('MACHINE_FEATURES', 'efi', 'systemd-efi.inc', '', d)} diff --git a/meta-arm/recipes-kernel/linux/linux-yocto%.bbappend b/meta-arm/recipes-kernel/linux/linux-yocto%.bbappend index a287d0e1..71e643a9 100644 --- a/meta-arm/recipes-kernel/linux/linux-yocto%.bbappend +++ b/meta-arm/recipes-kernel/linux/linux-yocto%.bbappend @@ -25,3 +25,5 @@ SRC_URI:append:qemuarm = " \ FFA_TRANSPORT_INCLUDE = "${@bb.utils.contains('MACHINE_FEATURES', 'arm-ffa', 'arm-ffa-transport.inc', '' , d)}" require ${FFA_TRANSPORT_INCLUDE} + +require ${@bb.utils.contains('MACHINE_FEATURES', 'uefi-secureboot', 'linux-yocto-uefi-secureboot.inc', '', d)} diff --git a/meta-arm/recipes-kernel/linux/linux-yocto-uefi-secureboot.inc b/meta-arm/recipes-kernel/linux/linux-yocto-uefi-secureboot.inc new file mode 100644 index 00000000..5c1f4de7 --- /dev/null +++ b/meta-arm/recipes-kernel/linux/linux-yocto-uefi-secureboot.inc @@ -0,0 +1,14 @@ +KERNEL_FEATURES += "cfg/efi-ext.scc" + +inherit sbsign + +# shell variable set inside do_compile task +SBSIGN_TARGET_BINARY = "$KERNEL_IMAGE" + +do_compile:append() { + KERNEL_IMAGE=$(find ${B} -name ${KERNEL_IMAGETYPE} -print -quit) + do_sbsign +} + +RRECOMMENDS:${PN} += "kernel-module-efivarfs" +RRECOMMENDS:${PN} += "kernel-module-efivars"