U-Boot

# SPDX-License-Identifier: GPL-2.0+
# Copyright (c) 2023 Linaro Limited
#
# Entry-type module for producing a EFI capsule
#

import os

from binman.entry import Entry
from binman.etype.section import Entry_section
from dtoc import fdt_util
from u_boot_pylib import tools

def get_binman_test_guid(type_str):
    """Get the test image GUID for binman

    Based on the string passed to the function, return
    the corresponding GUID.

    Args:
        type_str: Key value of the type of GUID to look for

    Returns:
        The actual GUID value (str)
    """
    TYPE_TO_GUID = {
        'binman-test' : '985f2937-7c2e-5e9a-8a5e-8e063312964b'
    }

    return TYPE_TO_GUID[type_str]

class Entry_efi_capsule(Entry_section):
    """Generate EFI capsules

    The parameters needed for generation of the capsules can
    be provided as properties in the entry.

    Properties / Entry arguments:
        - image-index: Unique number for identifying corresponding
          payload image. Number between 1 and descriptor count, i.e.
          the total number of firmware images that can be updated. Mandatory
          property.
        - image-guid: Image GUID which will be used for identifying the
          updatable image on the board. Mandatory property.
        - hardware-instance: Optional number for identifying unique
          hardware instance of a device in the system. Default value of 0
          for images where value is not to be used.
        - fw-version: Value of image version that can be put on the capsule
          through the Firmware Management Protocol(FMP) header.
        - monotonic-count: Count used when signing an image.
        - private-key: Path to PEM formatted .key private key file. Mandatory
          property for generating signed capsules.
        - public-key-cert: Path to PEM formatted .crt public key certificate
          file. Mandatory property for generating signed capsules.
        - oem-flags - OEM flags to be passed through capsule header.

    Since this is a subclass of Entry_section, all properties of the parent
    class also apply here. Except for the properties stated as mandatory, the
    rest of the properties are optional.

    For more details on the description of the capsule format, and the capsule
    update functionality, refer Section 8.5 and Chapter 23 in the `UEFI
    specification`_.

    The capsule parameters like image index and image GUID are passed as
    properties in the entry. The payload to be used in the capsule is to be
    provided as a subnode of the capsule entry.

    A typical capsule entry node would then look something like this::

        capsule {
            type = "efi-capsule";
            image-index = <0x1>;
            /* Image GUID for testing capsule update */
            image-guid = SANDBOX_UBOOT_IMAGE_GUID;
            hardware-instance = <0x0>;
            private-key = "path/to/the/private/key";
            public-key-cert = "path/to/the/public-key-cert";
            oem-flags = <0x8000>;

            u-boot {
            };
        };

    In the above example, the capsule payload is the U-Boot image. The
    capsule entry would read the contents of the payload and put them
    into the capsule. Any external file can also be specified as the
    payload using the blob-ext subnode.

    .. _`UEFI specification`: https://uefi.org/sites/default/files/resources/UEFI_Spec_2_10_Aug29.pdf
    """
    def __init__(self, section, etype, node):
        super().__init__(section, etype, node)
        self.required_props = ['image-index', 'image-guid']
        self.image_index = 0
        self.image_guid = ''
        self.hardware_instance = 0
        self.monotonic_count = 0
        self.fw_version = 0
        self.oem_flags = 0
        self.private_key = ''
        self.public_key_cert = ''
        self.auth = 0

    def ReadNode(self):
        super().ReadNode()

        self.image_index = fdt_util.GetInt(self._node, 'image-index')
        self.image_guid = fdt_util.GetString(self._node, 'image-guid')
        self.fw_version = fdt_util.GetInt(self._node, 'fw-version')
        self.hardware_instance = fdt_util.GetInt(self._node, 'hardware-instance')
        self.monotonic_count = fdt_util.GetInt(self._node, 'monotonic-count')
        self.oem_flags = fdt_util.GetInt(self._node, 'oem-flags')

        self.private_key = fdt_util.GetString(self._node, 'private-key')
        self.public_key_cert = fdt_util.GetString(self._node, 'public-key-cert')
        if ((self.private_key and not self.public_key_cert) or (self.public_key_cert and not self.private_key)):
            self.Raise('Both private key and public key certificate need to be provided')
        elif not (self.private_key and self.public_key_cert):
            self.auth = 0
        else:
            self.auth = 1

    def BuildSectionData(self, required):
        private_key = ''
        public_key_cert = ''
        if self.auth:
            if not os.path.isabs(self.private_key):
                private_key =  tools.get_input_filename(self.private_key)
            if not os.path.isabs(self.public_key_cert):
                public_key_cert = tools.get_input_filename(self.public_key_cert)
        data, payload, uniq = self.collect_contents_to_file(
            self._entries.values(), 'capsule_in')
        outfile = self._filename if self._filename else 'capsule.%s' % uniq
        capsule_fname = tools.get_output_filename(outfile)
        guid = self.image_guid
        if self.image_guid == "binman-test":
            guid = get_binman_test_guid('binman-test')

        ret = self.mkeficapsule.generate_capsule(self.image_index,
                                                 guid,
                                                 self.hardware_instance,
                                                 payload,
                                                 capsule_fname,
                                                 private_key,
                                                 public_key_cert,
                                                 self.monotonic_count,
                                                 self.fw_version,
                                                 self.oem_flags)
        if ret is not None:
            return tools.read_file(capsule_fname)
        else:
            # Bintool is missing; just use the input data as the output
            if not self.GetAllowMissing():
                self.Raise("Missing tool: 'mkeficapsule'")
            self.record_missing_bintool(self.mkeficapsule)
            return data

    def AddBintools(self, btools):
        self.mkeficapsule = self.AddBintool(btools, 'mkeficapsule')