+++ /dev/null
-.. SPDX-License-Identifier: GPL-2.0+
-.. Copyright (C) 2020, Linaro Limited
-
-Enabling UEFI Capsule Update feature
-------------------------------------
-
-Support has been added for the UEFI capsule update feature which
-enables updating the U-Boot image using the UEFI firmware management
-protocol (fmp). The capsules are not passed to the firmware through
-the UpdateCapsule runtime service. Instead, capsule-on-disk
-functionality is used for fetching the capsule from the EFI System
-Partition (ESP) by placing the capsule file under the
-\EFI\UpdateCapsule directory.
-
-Currently, support has been added on the QEMU ARM64 virt platform for
-updating the U-Boot binary as a raw image when the platform is booted
-in non-secure mode, i.e. with CONFIG_TFABOOT disabled. For this
-configuration, the QEMU platform needs to be booted with
-'secure=off'. The U-Boot binary placed on the first bank of the NOR
-flash at offset 0x0. The U-Boot environment is placed on the second
-NOR flash bank at offset 0x4000000.
-
-The capsule update feature is enabled with the following configuration
-settings::
-
- CONFIG_MTD=y
- CONFIG_FLASH_CFI_MTD=y
- CONFIG_CMD_MTDPARTS=y
- CONFIG_CMD_DFU=y
- CONFIG_DFU_MTD=y
- CONFIG_PCI_INIT_R=y
- CONFIG_EFI_CAPSULE_ON_DISK=y
- CONFIG_EFI_CAPSULE_FIRMWARE_MANAGEMENT=y
- CONFIG_EFI_CAPSULE_FIRMWARE=y
- CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y
- CONFIG_EFI_CAPSULE_FMP_HEADER=y
-
-In addition, the following config needs to be disabled(QEMU ARM specific)::
-
- CONFIG_TFABOOT
-
-The capsule file can be generated by using the tools/mkeficapsule::
-
- $ mkeficapsule --raw <u-boot.bin> --index 1 <capsule_file_name>
-
-As per the UEFI specification, the capsule file needs to be placed on
-the EFI System Partition, under the \EFI\UpdateCapsule directory. The
-EFI System Partition can be a virtio-blk-device.
-
-Before initiating the firmware update, the efi variables BootNext,
-BootXXXX and OsIndications need to be set. The BootXXXX variable needs
-to be pointing to the EFI System Partition which contains the capsule
-file. The BootNext, BootXXXX and OsIndications variables can be set
-using the following commands::
-
- => efidebug boot add -b 0 Boot0000 virtio 0:1 <capsule_file_name>
- => efidebug boot next 0
- => setenv -e -nv -bs -rt -v OsIndications =0x04
- => saveenv
-
-Finally, the capsule update can be initiated with the following
-command::
-
- => efidebug capsule disk-update
-
-The updated U-Boot image will be booted on subsequent boot.
-
-Enabling Capsule Authentication
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-The UEFI specification defines a way of authenticating the capsule to
-be updated by verifying the capsule signature. The capsule signature
-is computed and prepended to the capsule payload at the time of
-capsule generation. This signature is then verified by using the
-public key stored as part of the X509 certificate. This certificate is
-in the form of an efi signature list (esl) file, which is embedded as
-part of the platform's device tree blob using the mkeficapsule
-utility.
-
-On the QEMU virt platforms, the device-tree is generated on the fly
-based on the devices configured. This device tree is then passed on to
-the various software components booting on the platform, including
-U-Boot. Therefore, on the QEMU virt platform, the signatute is
-embedded on an overlay. This overlay is then applied at runtime to the
-base platform device-tree. Steps needed for embedding the esl file in
-the overlay are highlighted below.
-
-The capsule authentication feature can be enabled through the
-following config, in addition to the configs listed above for capsule
-update::
-
- CONFIG_EFI_CAPSULE_AUTHENTICATE=y
-
-The public and private keys used for the signing process are generated
-and used by the steps highlighted below::
-
- 1. Install utility commands on your host
- * OPENSSL
- * efitools
-
- 2. Create signing keys and certificate files on your host
-
- $ openssl req -x509 -sha256 -newkey rsa:2048 -subj /CN=CRT/ \
- -keyout CRT.key -out CRT.crt -nodes -days 365
- $ cert-to-efi-sig-list CRT.crt CRT.esl
-
- $ openssl x509 -in CRT.crt -out CRT.cer -outform DER
- $ openssl x509 -inform DER -in CRT.cer -outform PEM -out CRT.pub.pem
-
- $ openssl pkcs12 -export -out CRT.pfx -inkey CRT.key -in CRT.crt
- $ openssl pkcs12 -in CRT.pfx -nodes -out CRT.pem
-
-The capsule file can be generated by using the GenerateCapsule.py
-script in EDKII::
-
- $ ./BaseTools/BinWrappers/PosixLike/GenerateCapsule -e -o \
- <capsule_file_name> --monotonic-count <val> --fw-version \
- <val> --lsv <val> --guid \
- e2bb9c06-70e9-4b14-97a3-5a7913176e3f --verbose \
- --update-image-index <val> --signer-private-cert \
- /path/to/CRT.pem --trusted-public-cert \
- /path/to/CRT.pub.pem --other-public-cert /path/to/CRT.pub.pem \
- <u-boot.bin>
-
-Place the capsule generated in the above step on the EFI System
-Partition under the EFI/UpdateCapsule directory
-
-For embedding the public key certificate, the following steps need to
-be followed::
-
- 1. Generate a skeleton overlay dts file, with a single fragment
- node and an empty __overlay__ node
-
- A typical skeleton overlay file will look like this
-
- /dts-v1/;
- /plugin/;
-
- / {
- fragment@0 {
- target-path = "/";
- __overlay__ {
- };
- };
- };
-
-
- 2. Convert the dts to a corresponding dtb with the following
- command
- ./scripts/dtc/dtc -@ -I dts -O dtb -o <ov_dtb_file_name> \
- <dts_file>
-
- 3. Run the dtb file generated above through the mkeficapsule tool
- in U-Boot
- ./tools/mkeficapsule -O <pub_key.esl> -D <ov_dtb>
-
-Running the above command results in the creation of a 'signature'
-node in the dtb, under which the public key is stored as a
-'capsule-key' property. The '-O' option is to be used since the
-public key certificate(esl) file is being embedded in an overlay.
-
-The dtb file embedded with the certificate is now to be placed on an
-EFI System Partition. This would then be loaded and "merged" with the
-base platform flattened device-tree(dtb) at runtime.
-
-Build U-Boot with the following steps(QEMU ARM64)::
-
- $ make qemu_arm64_defconfig
- $ make menuconfig
- Disable CONFIG_TFABOOT
- Enable CONFIG_EFI_CAPSULE_AUTHENTICATE
- Enable all configs needed for capsule update(listed above)
- $ make all
-
-Boot the platform and perform the following steps on the U-Boot
-command line::
-
- 1. Enable capsule authentication by setting the following env
- variable
-
- => setenv capsule_authentication_enabled 1
- => saveenv
-
- 2. Load the overlay dtb to memory and merge it with the base fdt
-
- => fatload virtio 0:1 <$fdtovaddr> EFI/<ov_dtb_file>
- => fdt addr $fdtcontroladdr
- => fdt resize <size_of_ov_dtb_file>
- => fdt apply <$fdtovaddr>
-
- 3. Set the following environment and UEFI boot variables
-
- => setenv -e -nv -bs -rt -v OsIndications =0x04
- => efidebug boot add -b 0 Boot0000 virtio 0:1 <capsule_file_name>
- => efidebug boot next 0
- => saveenv
-
- 4. Finally, the capsule update can be initiated with the following
- command
-
- => efidebug capsule disk-update
-
-On subsequent reboot, the platform should boot the updated U-Boot binary.
[1] https://optee.readthedocs.io/en/latest/building/efi_vars/stmm.html
+Enabling UEFI Capsule Update feature
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Support has been added for the UEFI capsule update feature which
+enables updating the U-Boot image using the UEFI firmware management
+protocol (FMP). The capsules are not passed to the firmware through
+the UpdateCapsule runtime service. Instead, capsule-on-disk
+functionality is used for fetching the capsule from the EFI System
+Partition (ESP) by placing the capsule file under the
+\EFI\UpdateCapsule directory.
+
+The directory \EFI\UpdateCapsule is checked for capsules only within the
+EFI system partition on the device specified in the active boot option
+determined by reference to BootNext variable or BootOrder variable processing.
+The active Boot Variable is the variable with highest priority BootNext or
+within BootOrder that refers to a device found to be present. Boot variables
+in BootOrder but referring to devices not present are ignored when determining
+active boot variable.
+Before starting a capsule update make sure your capsules are installed in the
+correct ESP partition or set BootNext.
+
+Performing the update
+*********************
+
+Since U-boot doesn't currently support SetVariable at runtime there's a Kconfig
+option (CONFIG_EFI_IGNORE_OSINDICATIONS) to disable the OsIndications variable
+check. If that option is enabled just copy your capsule to \EFI\UpdateCapsule.
+
+If that option is disabled, you'll need to set the OsIndications variable with::
+
+ => setenv -e -nv -bs -rt -v OsIndications =0x04
+
+Finally, the capsule update can be initiated either by rebooting the board,
+which is the preferred method, or by issuing the following command::
+
+ => efidebug capsule disk-update
+
+**The efidebug command is should only be used during debugging/development.**
+
+Enabling Capsule Authentication
+*******************************
+
+The UEFI specification defines a way of authenticating the capsule to
+be updated by verifying the capsule signature. The capsule signature
+is computed and prepended to the capsule payload at the time of
+capsule generation. This signature is then verified by using the
+public key stored as part of the X509 certificate. This certificate is
+in the form of an efi signature list (esl) file, which is embedded as
+part of U-Boot.
+
+The capsule authentication feature can be enabled through the
+following config, in addition to the configs listed above for capsule
+update::
+
+ CONFIG_EFI_CAPSULE_AUTHENTICATE=y
+ CONFIG_EFI_CAPSULE_KEY_PATH=<path to .esl cert>
+
+The public and private keys used for the signing process are generated
+and used by the steps highlighted below::
+
+ 1. Install utility commands on your host
+ * OPENSSL
+ * efitools
+
+ 2. Create signing keys and certificate files on your host
+
+ $ openssl req -x509 -sha256 -newkey rsa:2048 -subj /CN=CRT/ \
+ -keyout CRT.key -out CRT.crt -nodes -days 365
+ $ cert-to-efi-sig-list CRT.crt CRT.esl
+
+ $ openssl x509 -in CRT.crt -out CRT.cer -outform DER
+ $ openssl x509 -inform DER -in CRT.cer -outform PEM -out CRT.pub.pem
+
+ $ openssl pkcs12 -export -out CRT.pfx -inkey CRT.key -in CRT.crt
+ $ openssl pkcs12 -in CRT.pfx -nodes -out CRT.pem
+
+The capsule file can be generated by using the GenerateCapsule.py
+script in EDKII::
+
+ $ ./BaseTools/BinWrappers/PosixLike/GenerateCapsule -e -o \
+ <capsule_file_name> --monotonic-count <val> --fw-version \
+ <val> --lsv <val> --guid \
+ e2bb9c06-70e9-4b14-97a3-5a7913176e3f --verbose \
+ --update-image-index <val> --signer-private-cert \
+ /path/to/CRT.pem --trusted-public-cert \
+ /path/to/CRT.pub.pem --other-public-cert /path/to/CRT.pub.pem \
+ <u-boot.bin>
+
+Place the capsule generated in the above step on the EFI System
+Partition under the EFI/UpdateCapsule directory
+
+Testing on QEMU
+***************
+
+Currently, support has been added on the QEMU ARM64 virt platform for
+updating the U-Boot binary as a raw image when the platform is booted
+in non-secure mode, i.e. with CONFIG_TFABOOT disabled. For this
+configuration, the QEMU platform needs to be booted with
+'secure=off'. The U-Boot binary placed on the first bank of the NOR
+flash at offset 0x0. The U-Boot environment is placed on the second
+NOR flash bank at offset 0x4000000.
+
+The capsule update feature is enabled with the following configuration
+settings::
+
+ CONFIG_MTD=y
+ CONFIG_FLASH_CFI_MTD=y
+ CONFIG_CMD_MTDPARTS=y
+ CONFIG_CMD_DFU=y
+ CONFIG_DFU_MTD=y
+ CONFIG_PCI_INIT_R=y
+ CONFIG_EFI_CAPSULE_ON_DISK=y
+ CONFIG_EFI_CAPSULE_FIRMWARE_MANAGEMENT=y
+ CONFIG_EFI_CAPSULE_FIRMWARE=y
+ CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y
+ CONFIG_EFI_CAPSULE_FMP_HEADER=y
+
+In addition, the following config needs to be disabled(QEMU ARM specific)::
+
+ CONFIG_TFABOOT
+
+The capsule file can be generated by using the tools/mkeficapsule::
+
+ $ mkeficapsule --raw <u-boot.bin> --index 1 <capsule_file_name>
+
Executing the boot manager
~~~~~~~~~~~~~~~~~~~~~~~~~~