781 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			781 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
	
// SPDX-License-Identifier: GPL-2.0+
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/*
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 *  EFI image loader
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 *
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 *  based partly on wine code
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 *
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 *  Copyright (c) 2016 Alexander Graf
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 */
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#include <common.h>
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#include <cpu_func.h>
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#include <efi_loader.h>
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#include <malloc.h>
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#include <pe.h>
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#include <sort.h>
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#include "../lib/crypto/pkcs7_parser.h"
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const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
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const efi_guid_t efi_guid_device_path = EFI_DEVICE_PATH_PROTOCOL_GUID;
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const efi_guid_t efi_guid_loaded_image = EFI_LOADED_IMAGE_PROTOCOL_GUID;
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const efi_guid_t efi_guid_loaded_image_device_path =
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		EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL_GUID;
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const efi_guid_t efi_simple_file_system_protocol_guid =
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		EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
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const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
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static int machines[] = {
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#if defined(__aarch64__)
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	IMAGE_FILE_MACHINE_ARM64,
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#elif defined(__arm__)
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	IMAGE_FILE_MACHINE_ARM,
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	IMAGE_FILE_MACHINE_THUMB,
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	IMAGE_FILE_MACHINE_ARMNT,
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#endif
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#if defined(__x86_64__)
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	IMAGE_FILE_MACHINE_AMD64,
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#elif defined(__i386__)
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	IMAGE_FILE_MACHINE_I386,
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#endif
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#if defined(__riscv) && (__riscv_xlen == 32)
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	IMAGE_FILE_MACHINE_RISCV32,
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#endif
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#if defined(__riscv) && (__riscv_xlen == 64)
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	IMAGE_FILE_MACHINE_RISCV64,
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#endif
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	0 };
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/**
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 * efi_print_image_info() - print information about a loaded image
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 *
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 * If the program counter is located within the image the offset to the base
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 * address is shown.
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 *
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 * @obj:	EFI object
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 * @image:	loaded image
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 * @pc:		program counter (use NULL to suppress offset output)
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 * Return:	status code
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 */
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static efi_status_t efi_print_image_info(struct efi_loaded_image_obj *obj,
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					 struct efi_loaded_image *image,
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					 void *pc)
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{
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	printf("UEFI image");
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	printf(" [0x%p:0x%p]",
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	       image->image_base, image->image_base + image->image_size - 1);
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	if (pc && pc >= image->image_base &&
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	    pc < image->image_base + image->image_size)
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		printf(" pc=0x%zx", pc - image->image_base);
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	if (image->file_path)
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		printf(" '%pD'", image->file_path);
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	printf("\n");
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	return EFI_SUCCESS;
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}
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/**
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 * efi_print_image_infos() - print information about all loaded images
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 *
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 * @pc:		program counter (use NULL to suppress offset output)
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 */
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void efi_print_image_infos(void *pc)
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{
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	struct efi_object *efiobj;
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	struct efi_handler *handler;
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	list_for_each_entry(efiobj, &efi_obj_list, link) {
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		list_for_each_entry(handler, &efiobj->protocols, link) {
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			if (!guidcmp(handler->guid, &efi_guid_loaded_image)) {
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				efi_print_image_info(
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					(struct efi_loaded_image_obj *)efiobj,
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					handler->protocol_interface, pc);
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			}
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		}
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	}
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}
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/**
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 * efi_loader_relocate() - relocate UEFI binary
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 *
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 * @rel:		pointer to the relocation table
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 * @rel_size:		size of the relocation table in bytes
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 * @efi_reloc:		actual load address of the image
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 * @pref_address:	preferred load address of the image
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 * Return:		status code
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 */
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static efi_status_t efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
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			unsigned long rel_size, void *efi_reloc,
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			unsigned long pref_address)
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{
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	unsigned long delta = (unsigned long)efi_reloc - pref_address;
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	const IMAGE_BASE_RELOCATION *end;
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	int i;
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	if (delta == 0)
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		return EFI_SUCCESS;
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	end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
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	while (rel < end && rel->SizeOfBlock) {
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		const uint16_t *relocs = (const uint16_t *)(rel + 1);
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		i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
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		while (i--) {
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			uint32_t offset = (uint32_t)(*relocs & 0xfff) +
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					  rel->VirtualAddress;
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			int type = *relocs >> EFI_PAGE_SHIFT;
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			uint64_t *x64 = efi_reloc + offset;
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			uint32_t *x32 = efi_reloc + offset;
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			uint16_t *x16 = efi_reloc + offset;
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			switch (type) {
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			case IMAGE_REL_BASED_ABSOLUTE:
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				break;
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			case IMAGE_REL_BASED_HIGH:
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				*x16 += ((uint32_t)delta) >> 16;
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				break;
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			case IMAGE_REL_BASED_LOW:
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				*x16 += (uint16_t)delta;
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				break;
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			case IMAGE_REL_BASED_HIGHLOW:
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				*x32 += (uint32_t)delta;
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				break;
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			case IMAGE_REL_BASED_DIR64:
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				*x64 += (uint64_t)delta;
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				break;
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#ifdef __riscv
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			case IMAGE_REL_BASED_RISCV_HI20:
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				*x32 = ((*x32 & 0xfffff000) + (uint32_t)delta) |
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					(*x32 & 0x00000fff);
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				break;
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			case IMAGE_REL_BASED_RISCV_LOW12I:
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			case IMAGE_REL_BASED_RISCV_LOW12S:
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				/* We know that we're 4k aligned */
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				if (delta & 0xfff) {
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					printf("Unsupported reloc offset\n");
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					return EFI_LOAD_ERROR;
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				}
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				break;
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#endif
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			default:
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				printf("Unknown Relocation off %x type %x\n",
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				       offset, type);
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				return EFI_LOAD_ERROR;
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			}
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			relocs++;
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		}
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		rel = (const IMAGE_BASE_RELOCATION *)relocs;
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	}
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	return EFI_SUCCESS;
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}
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void __weak invalidate_icache_all(void)
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{
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	/* If the system doesn't support icache_all flush, cross our fingers */
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}
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/**
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 * efi_set_code_and_data_type() - determine the memory types to be used for code
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 *				  and data.
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 *
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 * @loaded_image_info:	image descriptor
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 * @image_type:		field Subsystem of the optional header for
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 *			Windows specific field
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 */
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static void efi_set_code_and_data_type(
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			struct efi_loaded_image *loaded_image_info,
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			uint16_t image_type)
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{
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	switch (image_type) {
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	case IMAGE_SUBSYSTEM_EFI_APPLICATION:
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		loaded_image_info->image_code_type = EFI_LOADER_CODE;
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		loaded_image_info->image_data_type = EFI_LOADER_DATA;
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		break;
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	case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
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		loaded_image_info->image_code_type = EFI_BOOT_SERVICES_CODE;
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		loaded_image_info->image_data_type = EFI_BOOT_SERVICES_DATA;
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		break;
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	case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
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	case IMAGE_SUBSYSTEM_EFI_ROM:
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		loaded_image_info->image_code_type = EFI_RUNTIME_SERVICES_CODE;
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		loaded_image_info->image_data_type = EFI_RUNTIME_SERVICES_DATA;
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		break;
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	default:
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		printf("%s: invalid image type: %u\n", __func__, image_type);
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		/* Let's assume it is an application */
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		loaded_image_info->image_code_type = EFI_LOADER_CODE;
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		loaded_image_info->image_data_type = EFI_LOADER_DATA;
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		break;
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	}
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}
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#ifdef CONFIG_EFI_SECURE_BOOT
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/**
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 * cmp_pe_section - compare two sections
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 * @arg1:	Pointer to pointer to first section
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 * @arg2:	Pointer to pointer to second section
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 *
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 * Compare two sections in PE image.
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 *
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 * Return:	-1, 0, 1 respectively if arg1 < arg2, arg1 == arg2 or
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 *		arg1 > arg2
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 */
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static int cmp_pe_section(const void *arg1, const void *arg2)
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{
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	const IMAGE_SECTION_HEADER *section1, *section2;
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	section1 = *((const IMAGE_SECTION_HEADER **)arg1);
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	section2 = *((const IMAGE_SECTION_HEADER **)arg2);
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	if (section1->VirtualAddress < section2->VirtualAddress)
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		return -1;
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	else if (section1->VirtualAddress == section2->VirtualAddress)
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		return 0;
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	else
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		return 1;
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}
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/**
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 * efi_image_parse - parse a PE image
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 * @efi:	Pointer to image
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 * @len:	Size of @efi
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 * @regp:	Pointer to a list of regions
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 * @auth:	Pointer to a pointer to authentication data in PE
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 * @auth_len:	Size of @auth
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 *
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 * Parse image binary in PE32(+) format, assuming that sanity of PE image
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 * has been checked by a caller.
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 * On success, an address of authentication data in @efi and its size will
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 * be returned in @auth and @auth_len, respectively.
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 *
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 * Return:	true on success, false on error
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 */
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bool efi_image_parse(void *efi, size_t len, struct efi_image_regions **regp,
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		     WIN_CERTIFICATE **auth, size_t *auth_len)
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{
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	struct efi_image_regions *regs;
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	IMAGE_DOS_HEADER *dos;
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	IMAGE_NT_HEADERS32 *nt;
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	IMAGE_SECTION_HEADER *sections, **sorted;
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	int num_regions, num_sections, i;
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	int ctidx = IMAGE_DIRECTORY_ENTRY_SECURITY;
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	u32 align, size, authsz, authoff;
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	size_t bytes_hashed;
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	dos = (void *)efi;
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	nt = (void *)(efi + dos->e_lfanew);
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	/*
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	 * Count maximum number of regions to be digested.
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	 * We don't have to have an exact number here.
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	 * See efi_image_region_add()'s in parsing below.
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	 */
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	num_regions = 3; /* for header */
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	num_regions += nt->FileHeader.NumberOfSections;
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	num_regions++; /* for extra */
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	regs = calloc(sizeof(*regs) + sizeof(struct image_region) * num_regions,
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		      1);
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	if (!regs)
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		goto err;
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	regs->max = num_regions;
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	/*
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	 * Collect data regions for hash calculation
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	 * 1. File headers
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	 */
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	if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
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		IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
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		IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
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		/* Skip CheckSum */
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		efi_image_region_add(regs, efi, &opt->CheckSum, 0);
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		if (nt64->OptionalHeader.NumberOfRvaAndSizes <= ctidx) {
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			efi_image_region_add(regs,
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					     &opt->CheckSum + 1,
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					     efi + opt->SizeOfHeaders, 0);
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		} else {
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			/* Skip Certificates Table */
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			efi_image_region_add(regs,
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					     &opt->CheckSum + 1,
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					     &opt->DataDirectory[ctidx], 0);
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			efi_image_region_add(regs,
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					     &opt->DataDirectory[ctidx] + 1,
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					     efi + opt->SizeOfHeaders, 0);
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		}
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		bytes_hashed = opt->SizeOfHeaders;
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		align = opt->FileAlignment;
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		authoff = opt->DataDirectory[ctidx].VirtualAddress;
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		authsz = opt->DataDirectory[ctidx].Size;
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	} else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
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		IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
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		efi_image_region_add(regs, efi, &opt->CheckSum, 0);
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		efi_image_region_add(regs, &opt->CheckSum + 1,
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				     &opt->DataDirectory[ctidx], 0);
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		efi_image_region_add(regs, &opt->DataDirectory[ctidx] + 1,
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				     efi + opt->SizeOfHeaders, 0);
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		bytes_hashed = opt->SizeOfHeaders;
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		align = opt->FileAlignment;
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		authoff = opt->DataDirectory[ctidx].VirtualAddress;
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		authsz = opt->DataDirectory[ctidx].Size;
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	} else {
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		debug("%s: Invalid optional header magic %x\n", __func__,
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		      nt->OptionalHeader.Magic);
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		goto err;
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	}
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	/* 2. Sections */
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	num_sections = nt->FileHeader.NumberOfSections;
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	sections = (void *)((uint8_t *)&nt->OptionalHeader +
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			    nt->FileHeader.SizeOfOptionalHeader);
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	sorted = calloc(sizeof(IMAGE_SECTION_HEADER *), num_sections);
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	if (!sorted) {
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		debug("%s: Out of memory\n", __func__);
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		goto err;
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	}
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	/*
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	 * Make sure the section list is in ascending order.
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	 */
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	for (i = 0; i < num_sections; i++)
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		sorted[i] = §ions[i];
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	qsort(sorted, num_sections, sizeof(sorted[0]), cmp_pe_section);
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	for (i = 0; i < num_sections; i++) {
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		if (!sorted[i]->SizeOfRawData)
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			continue;
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		size = (sorted[i]->SizeOfRawData + align - 1) & ~(align - 1);
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		efi_image_region_add(regs, efi + sorted[i]->PointerToRawData,
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				     efi + sorted[i]->PointerToRawData + size,
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				     0);
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		debug("section[%d](%s): raw: 0x%x-0x%x, virt: %x-%x\n",
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		      i, sorted[i]->Name,
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		      sorted[i]->PointerToRawData,
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		      sorted[i]->PointerToRawData + size,
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		      sorted[i]->VirtualAddress,
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		      sorted[i]->VirtualAddress
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			+ sorted[i]->Misc.VirtualSize);
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		bytes_hashed += size;
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	}
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	free(sorted);
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	/* 3. Extra data excluding Certificates Table */
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	if (bytes_hashed + authsz < len) {
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		debug("extra data for hash: %lu\n",
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		      len - (bytes_hashed + authsz));
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		efi_image_region_add(regs, efi + bytes_hashed,
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				     efi + len - authsz, 0);
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	}
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	/* Return Certificates Table */
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	if (authsz) {
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		if (len < authoff + authsz) {
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			debug("%s: Size for auth too large: %u >= %zu\n",
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			      __func__, authsz, len - authoff);
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			goto err;
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		}
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		if (authsz < sizeof(*auth)) {
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			debug("%s: Size for auth too small: %u < %zu\n",
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			      __func__, authsz, sizeof(*auth));
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			goto err;
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		}
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		*auth = efi + authoff;
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		*auth_len = authsz;
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		debug("WIN_CERTIFICATE: 0x%x, size: 0x%x\n", authoff, authsz);
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	} else {
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		*auth = NULL;
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		*auth_len = 0;
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	}
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	*regp = regs;
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	return true;
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err:
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	free(regs);
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	return false;
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}
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/**
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 * efi_image_unsigned_authenticate - authenticate unsigned image with
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 * SHA256 hash
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 * @regs:	List of regions to be verified
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 *
 | 
						|
 * If an image is not signed, it doesn't have a signature. In this case,
 | 
						|
 * its message digest is calculated and it will be compared with one of
 | 
						|
 * hash values stored in signature databases.
 | 
						|
 *
 | 
						|
 * Return:	true if authenticated, false if not
 | 
						|
 */
 | 
						|
static bool efi_image_unsigned_authenticate(struct efi_image_regions *regs)
 | 
						|
{
 | 
						|
	struct efi_signature_store *db = NULL, *dbx = NULL;
 | 
						|
	bool ret = false;
 | 
						|
 | 
						|
	dbx = efi_sigstore_parse_sigdb(L"dbx");
 | 
						|
	if (!dbx) {
 | 
						|
		debug("Getting signature database(dbx) failed\n");
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
 | 
						|
	db = efi_sigstore_parse_sigdb(L"db");
 | 
						|
	if (!db) {
 | 
						|
		debug("Getting signature database(db) failed\n");
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
 | 
						|
	/* try black-list first */
 | 
						|
	if (efi_signature_verify_with_sigdb(regs, NULL, dbx, NULL)) {
 | 
						|
		debug("Image is not signed and rejected by \"dbx\"\n");
 | 
						|
		goto out;
 | 
						|
	}
 | 
						|
 | 
						|
	/* try white-list */
 | 
						|
	if (efi_signature_verify_with_sigdb(regs, NULL, db, NULL))
 | 
						|
		ret = true;
 | 
						|
	else
 | 
						|
		debug("Image is not signed and not found in \"db\" or \"dbx\"\n");
 | 
						|
 | 
						|
out:
 | 
						|
	efi_sigstore_free(db);
 | 
						|
	efi_sigstore_free(dbx);
 | 
						|
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * efi_image_authenticate - verify a signature of signed image
 | 
						|
 * @efi:	Pointer to image
 | 
						|
 * @efi_size:	Size of @efi
 | 
						|
 *
 | 
						|
 * A signed image should have its signature stored in a table of its PE header.
 | 
						|
 * So if an image is signed and only if if its signature is verified using
 | 
						|
 * signature databases, an image is authenticated.
 | 
						|
 * If an image is not signed, its validity is checked by using
 | 
						|
 * efi_image_unsigned_authenticated().
 | 
						|
 * TODO:
 | 
						|
 * When AuditMode==0, if the image's signature is not found in
 | 
						|
 * the authorized database, or is found in the forbidden database,
 | 
						|
 * the image will not be started and instead, information about it
 | 
						|
 * will be placed in this table.
 | 
						|
 * When AuditMode==1, an EFI_IMAGE_EXECUTION_INFO element is created
 | 
						|
 * in the EFI_IMAGE_EXECUTION_INFO_TABLE for every certificate found
 | 
						|
 * in the certificate table of every image that is validated.
 | 
						|
 *
 | 
						|
 * Return:	true if authenticated, false if not
 | 
						|
 */
 | 
						|
static bool efi_image_authenticate(void *efi, size_t efi_size)
 | 
						|
{
 | 
						|
	struct efi_image_regions *regs = NULL;
 | 
						|
	WIN_CERTIFICATE *wincerts = NULL, *wincert;
 | 
						|
	size_t wincerts_len;
 | 
						|
	struct pkcs7_message *msg = NULL;
 | 
						|
	struct efi_signature_store *db = NULL, *dbx = NULL;
 | 
						|
	struct x509_certificate *cert = NULL;
 | 
						|
	void *new_efi = NULL;
 | 
						|
	size_t new_efi_size;
 | 
						|
	bool ret = false;
 | 
						|
 | 
						|
	if (!efi_secure_boot_enabled())
 | 
						|
		return true;
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Size must be 8-byte aligned and the trailing bytes must be
 | 
						|
	 * zero'ed. Otherwise hash value may be incorrect.
 | 
						|
	 */
 | 
						|
	if (efi_size & 0x7) {
 | 
						|
		new_efi_size = (efi_size + 0x7) & ~0x7ULL;
 | 
						|
		new_efi = calloc(new_efi_size, 1);
 | 
						|
		if (!new_efi)
 | 
						|
			return false;
 | 
						|
		memcpy(new_efi, efi, efi_size);
 | 
						|
		efi = new_efi;
 | 
						|
		efi_size = new_efi_size;
 | 
						|
	}
 | 
						|
 | 
						|
	if (!efi_image_parse(efi, efi_size, ®s, &wincerts,
 | 
						|
			     &wincerts_len)) {
 | 
						|
		debug("Parsing PE executable image failed\n");
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	if (!wincerts) {
 | 
						|
		/* The image is not signed */
 | 
						|
		ret = efi_image_unsigned_authenticate(regs);
 | 
						|
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	/*
 | 
						|
	 * verify signature using db and dbx
 | 
						|
	 */
 | 
						|
	db = efi_sigstore_parse_sigdb(L"db");
 | 
						|
	if (!db) {
 | 
						|
		debug("Getting signature database(db) failed\n");
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	dbx = efi_sigstore_parse_sigdb(L"dbx");
 | 
						|
	if (!dbx) {
 | 
						|
		debug("Getting signature database(dbx) failed\n");
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	/* go through WIN_CERTIFICATE list */
 | 
						|
	for (wincert = wincerts;
 | 
						|
	     (void *)wincert < (void *)wincerts + wincerts_len;
 | 
						|
	     wincert = (void *)wincert + ALIGN(wincert->dwLength, 8)) {
 | 
						|
		if (wincert->dwLength < sizeof(*wincert)) {
 | 
						|
			debug("%s: dwLength too small: %u < %zu\n",
 | 
						|
			      __func__, wincert->dwLength, sizeof(*wincert));
 | 
						|
			goto err;
 | 
						|
		}
 | 
						|
		msg = pkcs7_parse_message((void *)wincert + sizeof(*wincert),
 | 
						|
					  wincert->dwLength - sizeof(*wincert));
 | 
						|
		if (!msg) {
 | 
						|
			debug("Parsing image's signature failed\n");
 | 
						|
			goto err;
 | 
						|
		}
 | 
						|
 | 
						|
		/* try black-list first */
 | 
						|
		if (efi_signature_verify_with_sigdb(regs, msg, dbx, NULL)) {
 | 
						|
			debug("Signature was rejected by \"dbx\"\n");
 | 
						|
			goto err;
 | 
						|
		}
 | 
						|
 | 
						|
		if (!efi_signature_verify_signers(msg, dbx)) {
 | 
						|
			debug("Signer was rejected by \"dbx\"\n");
 | 
						|
			goto err;
 | 
						|
		} else {
 | 
						|
			ret = true;
 | 
						|
		}
 | 
						|
 | 
						|
		/* try white-list */
 | 
						|
		if (!efi_signature_verify_with_sigdb(regs, msg, db, &cert)) {
 | 
						|
			debug("Verifying signature with \"db\" failed\n");
 | 
						|
			goto err;
 | 
						|
		} else {
 | 
						|
			ret = true;
 | 
						|
		}
 | 
						|
 | 
						|
		if (!efi_signature_verify_cert(cert, dbx)) {
 | 
						|
			debug("Certificate was rejected by \"dbx\"\n");
 | 
						|
			goto err;
 | 
						|
		} else {
 | 
						|
			ret = true;
 | 
						|
		}
 | 
						|
	}
 | 
						|
 | 
						|
err:
 | 
						|
	x509_free_certificate(cert);
 | 
						|
	efi_sigstore_free(db);
 | 
						|
	efi_sigstore_free(dbx);
 | 
						|
	pkcs7_free_message(msg);
 | 
						|
	free(regs);
 | 
						|
	free(new_efi);
 | 
						|
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
#else
 | 
						|
static bool efi_image_authenticate(void *efi, size_t efi_size)
 | 
						|
{
 | 
						|
	return true;
 | 
						|
}
 | 
						|
#endif /* CONFIG_EFI_SECURE_BOOT */
 | 
						|
 | 
						|
/**
 | 
						|
 * efi_load_pe() - relocate EFI binary
 | 
						|
 *
 | 
						|
 * This function loads all sections from a PE binary into a newly reserved
 | 
						|
 * piece of memory. On success the entry point is returned as handle->entry.
 | 
						|
 *
 | 
						|
 * @handle:		loaded image handle
 | 
						|
 * @efi:		pointer to the EFI binary
 | 
						|
 * @efi_size:		size of @efi binary
 | 
						|
 * @loaded_image_info:	loaded image protocol
 | 
						|
 * Return:		status code
 | 
						|
 */
 | 
						|
efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
 | 
						|
			 void *efi, size_t efi_size,
 | 
						|
			 struct efi_loaded_image *loaded_image_info)
 | 
						|
{
 | 
						|
	IMAGE_NT_HEADERS32 *nt;
 | 
						|
	IMAGE_DOS_HEADER *dos;
 | 
						|
	IMAGE_SECTION_HEADER *sections;
 | 
						|
	int num_sections;
 | 
						|
	void *efi_reloc;
 | 
						|
	int i;
 | 
						|
	const IMAGE_BASE_RELOCATION *rel;
 | 
						|
	unsigned long rel_size;
 | 
						|
	int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
 | 
						|
	uint64_t image_base;
 | 
						|
	unsigned long virt_size = 0;
 | 
						|
	int supported = 0;
 | 
						|
	efi_status_t ret;
 | 
						|
 | 
						|
	/* Sanity check for a file header */
 | 
						|
	if (efi_size < sizeof(*dos)) {
 | 
						|
		printf("%s: Truncated DOS Header\n", __func__);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	dos = efi;
 | 
						|
	if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
 | 
						|
		printf("%s: Invalid DOS Signature\n", __func__);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	/* assume sizeof(IMAGE_NT_HEADERS32) <= sizeof(IMAGE_NT_HEADERS64) */
 | 
						|
	if (efi_size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS32)) {
 | 
						|
		printf("%s: Invalid offset for Extended Header\n", __func__);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	nt = (void *) ((char *)efi + dos->e_lfanew);
 | 
						|
	if ((nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) &&
 | 
						|
	    (efi_size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS64))) {
 | 
						|
		printf("%s: Invalid offset for Extended Header\n", __func__);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	if (nt->Signature != IMAGE_NT_SIGNATURE) {
 | 
						|
		printf("%s: Invalid NT Signature\n", __func__);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	for (i = 0; machines[i]; i++)
 | 
						|
		if (machines[i] == nt->FileHeader.Machine) {
 | 
						|
			supported = 1;
 | 
						|
			break;
 | 
						|
		}
 | 
						|
 | 
						|
	if (!supported) {
 | 
						|
		printf("%s: Machine type 0x%04x is not supported\n",
 | 
						|
		       __func__, nt->FileHeader.Machine);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	num_sections = nt->FileHeader.NumberOfSections;
 | 
						|
	sections = (void *)&nt->OptionalHeader +
 | 
						|
			    nt->FileHeader.SizeOfOptionalHeader;
 | 
						|
 | 
						|
	if (efi_size < ((void *)sections + sizeof(sections[0]) * num_sections
 | 
						|
			- efi)) {
 | 
						|
		printf("%s: Invalid number of sections: %d\n",
 | 
						|
		       __func__, num_sections);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	/* Authenticate an image */
 | 
						|
	if (efi_image_authenticate(efi, efi_size))
 | 
						|
		handle->auth_status = EFI_IMAGE_AUTH_PASSED;
 | 
						|
	else
 | 
						|
		handle->auth_status = EFI_IMAGE_AUTH_FAILED;
 | 
						|
 | 
						|
	/* Calculate upper virtual address boundary */
 | 
						|
	for (i = num_sections - 1; i >= 0; i--) {
 | 
						|
		IMAGE_SECTION_HEADER *sec = §ions[i];
 | 
						|
		virt_size = max_t(unsigned long, virt_size,
 | 
						|
				  sec->VirtualAddress + sec->Misc.VirtualSize);
 | 
						|
	}
 | 
						|
 | 
						|
	/* Read 32/64bit specific header bits */
 | 
						|
	if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 | 
						|
		IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 | 
						|
		IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 | 
						|
		image_base = opt->ImageBase;
 | 
						|
		efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 | 
						|
		handle->image_type = opt->Subsystem;
 | 
						|
		efi_reloc = efi_alloc(virt_size,
 | 
						|
				      loaded_image_info->image_code_type);
 | 
						|
		if (!efi_reloc) {
 | 
						|
			printf("%s: Could not allocate %lu bytes\n",
 | 
						|
			       __func__, virt_size);
 | 
						|
			ret = EFI_OUT_OF_RESOURCES;
 | 
						|
			goto err;
 | 
						|
		}
 | 
						|
		handle->entry = efi_reloc + opt->AddressOfEntryPoint;
 | 
						|
		rel_size = opt->DataDirectory[rel_idx].Size;
 | 
						|
		rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 | 
						|
		virt_size = ALIGN(virt_size, opt->SectionAlignment);
 | 
						|
	} else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 | 
						|
		IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 | 
						|
		image_base = opt->ImageBase;
 | 
						|
		efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 | 
						|
		handle->image_type = opt->Subsystem;
 | 
						|
		efi_reloc = efi_alloc(virt_size,
 | 
						|
				      loaded_image_info->image_code_type);
 | 
						|
		if (!efi_reloc) {
 | 
						|
			printf("%s: Could not allocate %lu bytes\n",
 | 
						|
			       __func__, virt_size);
 | 
						|
			ret = EFI_OUT_OF_RESOURCES;
 | 
						|
			goto err;
 | 
						|
		}
 | 
						|
		handle->entry = efi_reloc + opt->AddressOfEntryPoint;
 | 
						|
		rel_size = opt->DataDirectory[rel_idx].Size;
 | 
						|
		rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 | 
						|
		virt_size = ALIGN(virt_size, opt->SectionAlignment);
 | 
						|
	} else {
 | 
						|
		printf("%s: Invalid optional header magic %x\n", __func__,
 | 
						|
		       nt->OptionalHeader.Magic);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	/* Copy PE headers */
 | 
						|
	memcpy(efi_reloc, efi,
 | 
						|
	       sizeof(*dos)
 | 
						|
		 + sizeof(*nt)
 | 
						|
		 + nt->FileHeader.SizeOfOptionalHeader
 | 
						|
		 + num_sections * sizeof(IMAGE_SECTION_HEADER));
 | 
						|
 | 
						|
	/* Load sections into RAM */
 | 
						|
	for (i = num_sections - 1; i >= 0; i--) {
 | 
						|
		IMAGE_SECTION_HEADER *sec = §ions[i];
 | 
						|
		memset(efi_reloc + sec->VirtualAddress, 0,
 | 
						|
		       sec->Misc.VirtualSize);
 | 
						|
		memcpy(efi_reloc + sec->VirtualAddress,
 | 
						|
		       efi + sec->PointerToRawData,
 | 
						|
		       sec->SizeOfRawData);
 | 
						|
	}
 | 
						|
 | 
						|
	/* Run through relocations */
 | 
						|
	if (efi_loader_relocate(rel, rel_size, efi_reloc,
 | 
						|
				(unsigned long)image_base) != EFI_SUCCESS) {
 | 
						|
		efi_free_pages((uintptr_t) efi_reloc,
 | 
						|
			       (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
 | 
						|
		ret = EFI_LOAD_ERROR;
 | 
						|
		goto err;
 | 
						|
	}
 | 
						|
 | 
						|
	/* Flush cache */
 | 
						|
	flush_cache((ulong)efi_reloc,
 | 
						|
		    ALIGN(virt_size, EFI_CACHELINE_SIZE));
 | 
						|
	invalidate_icache_all();
 | 
						|
 | 
						|
	/* Populate the loaded image interface bits */
 | 
						|
	loaded_image_info->image_base = efi_reloc;
 | 
						|
	loaded_image_info->image_size = virt_size;
 | 
						|
 | 
						|
	if (handle->auth_status == EFI_IMAGE_AUTH_PASSED)
 | 
						|
		return EFI_SUCCESS;
 | 
						|
	else
 | 
						|
		return EFI_SECURITY_VIOLATION;
 | 
						|
 | 
						|
err:
 | 
						|
	return ret;
 | 
						|
}
 |