common/bl_common.c - filogic/atf - Gitiles

 /*
  * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

 #include <assert.h>
 #include <errno.h>
 #include <string.h>

 #include <arch.h>
 #include <arch_features.h>
 #include <arch_helpers.h>
 #include <common/bl_common.h>
 #include <common/debug.h>
 #include <drivers/auth/auth_mod.h>
 #include <drivers/io/io_storage.h>
 #include <lib/utils.h>
 #include <lib/xlat_tables/xlat_tables_defs.h>
 #include <plat/common/platform.h>

 #if TRUSTED_BOARD_BOOT
 # ifdef DYN_DISABLE_AUTH
 static int disable_auth;

 /******************************************************************************
  * API to dynamically disable authentication. Only meant for development
  * systems. This is only invoked if DYN_DISABLE_AUTH is defined.
  *****************************************************************************/
 void dyn_disable_auth(void)
 {
 	INFO("Disabling authentication of images dynamically\n");
 	disable_auth = 1;
 }
 # endif /* DYN_DISABLE_AUTH */

 /******************************************************************************
  * Function to determine whether the authentication is disabled dynamically.
  *****************************************************************************/
 static int dyn_is_auth_disabled(void)
 {
 # ifdef DYN_DISABLE_AUTH
 	return disable_auth;
 # else
 	return 0;
 # endif
 }
 #endif /* TRUSTED_BOARD_BOOT */

 uintptr_t page_align(uintptr_t value, unsigned dir)
 {
 	/* Round up the limit to the next page boundary */
 	if ((value & (PAGE_SIZE - 1U)) != 0U) {
 		value &= ~(PAGE_SIZE - 1U);
 		if (dir == UP)
 			value += PAGE_SIZE;
 	}

 	return value;
 }

 /*******************************************************************************
  * Internal function to load an image at a specific address given
  * an image ID and extents of free memory.
  *
  * If the load is successful then the image information is updated.
  *
  * Returns 0 on success, a negative error code otherwise.
  ******************************************************************************/
 static int load_image(unsigned int image_id, image_info_t *image_data)
 {
 	uintptr_t dev_handle;
 	uintptr_t image_handle;
 	uintptr_t image_spec;
 	uintptr_t image_base;
 	size_t image_size;
 	size_t bytes_read;
 	int io_result;

 	assert(image_data != NULL);
 	assert(image_data->h.version >= VERSION_2);

 	image_base = image_data->image_base;

 	/* Obtain a reference to the image by querying the platform layer */
 	io_result = plat_get_image_source(image_id, &dev_handle, &image_spec);
 	if (io_result != 0) {
 		WARN("Failed to obtain reference to image id=%u (%i)\n",
 			image_id, io_result);
 		return io_result;
 	}

 	/* Attempt to access the image */
 	io_result = io_open(dev_handle, image_spec, &image_handle);
 	if (io_result != 0) {
 		WARN("Failed to access image id=%u (%i)\n",
 			image_id, io_result);
 		return io_result;
 	}

 	INFO("Loading image id=%u at address 0x%lx\n", image_id, image_base);

 	/* Find the size of the image */
 	io_result = io_size(image_handle, &image_size);
 	if ((io_result != 0) || (image_size == 0U)) {
 		WARN("Failed to determine the size of the image id=%u (%i)\n",
 			image_id, io_result);
 		goto exit;
 	}

 	/* Check that the image size to load is within limit */
 	if (image_size > image_data->image_max_size) {
 		WARN("Image id=%u size out of bounds\n", image_id);
 		io_result = -EFBIG;
 		goto exit;
 	}

 	/*
 	 * image_data->image_max_size is a uint32_t so image_size will always
 	 * fit in image_data->image_size.
 	 */
 	image_data->image_size = (uint32_t)image_size;

 	/* We have enough space so load the image now */
 	/* TODO: Consider whether to try to recover/retry a partially successful read */
 	io_result = io_read(image_handle, image_base, image_size, &bytes_read);
 	if ((io_result != 0) || (bytes_read < image_size)) {
 		WARN("Failed to load image id=%u (%i)\n", image_id, io_result);
 		goto exit;
 	}

 	INFO("Image id=%u loaded: 0x%lx - 0x%lx\n", image_id, image_base,
 	     (uintptr_t)(image_base + image_size));

 exit:
 	(void)io_close(image_handle);
 	/* Ignore improbable/unrecoverable error in 'close' */

 	/* TODO: Consider maintaining open device connection from this bootloader stage */
 	(void)io_dev_close(dev_handle);
 	/* Ignore improbable/unrecoverable error in 'dev_close' */

 	return io_result;
 }

 static int load_auth_image_internal(unsigned int image_id,
 				    image_info_t *image_data,
 				    int is_parent_image)
 {
 	int rc;

 #if TRUSTED_BOARD_BOOT
 	if (dyn_is_auth_disabled() == 0) {
 		unsigned int parent_id;

 		/* Use recursion to authenticate parent images */
 		rc = auth_mod_get_parent_id(image_id, &parent_id);
 		if (rc == 0) {
 			rc = load_auth_image_internal(parent_id, image_data, 1);
 			if (rc != 0) {
 				return rc;
 			}
 		}
 	}
 #endif /* TRUSTED_BOARD_BOOT */

 	/* Load the image */
 	rc = load_image(image_id, image_data);
 	if (rc != 0) {
 		return rc;
 	}

 #if TRUSTED_BOARD_BOOT
 	if (dyn_is_auth_disabled() == 0) {
 		/* Authenticate it */
 		rc = auth_mod_verify_img(image_id,
 					 (void *)image_data->image_base,
 					 image_data->image_size);
 		if (rc != 0) {
 			/* Authentication error, zero memory and flush it right away. */
 			zero_normalmem((void *)image_data->image_base,
 			       image_data->image_size);
 			flush_dcache_range(image_data->image_base,
 					   image_data->image_size);
 			return -EAUTH;
 		}
 	}
 #endif /* TRUSTED_BOARD_BOOT */

 	/*
 	 * Flush the image to main memory so that it can be executed later by
 	 * any CPU, regardless of cache and MMU state. If TBB is enabled, then
 	 * the file has been successfully loaded and authenticated and flush
 	 * only for child images, not for the parents (certificates).
 	 */
 	if (is_parent_image == 0) {
 		flush_dcache_range(image_data->image_base,
 				   image_data->image_size);
 	}


 	return 0;
 }

 /*******************************************************************************
  * Generic function to load and authenticate an image. The image is actually
  * loaded by calling the 'load_image()' function. Therefore, it returns the
  * same error codes if the loading operation failed, or -EAUTH if the
  * authentication failed. In addition, this function uses recursion to
  * authenticate the parent images up to the root of trust.
  ******************************************************************************/
 int load_auth_image(unsigned int image_id, image_info_t *image_data)
 {
 	int err;

 	do {
 		err = load_auth_image_internal(image_id, image_data, 0);
 	} while ((err != 0) && (plat_try_next_boot_source() != 0));

 	return err;
 }

 /*******************************************************************************
  * Print the content of an entry_point_info_t structure.
  ******************************************************************************/
 void print_entry_point_info(const entry_point_info_t *ep_info)
 {
 	INFO("Entry point address = 0x%lx\n", ep_info->pc);
 	INFO("SPSR = 0x%x\n", ep_info->spsr);

 #define PRINT_IMAGE_ARG(n)					\
 	VERBOSE("Argument #" #n " = 0x%llx\n",			\
 		(unsigned long long) ep_info->args.arg##n)

 	PRINT_IMAGE_ARG(0);
 	PRINT_IMAGE_ARG(1);
 	PRINT_IMAGE_ARG(2);
 	PRINT_IMAGE_ARG(3);
 #ifndef AARCH32
 	PRINT_IMAGE_ARG(4);
 	PRINT_IMAGE_ARG(5);
 	PRINT_IMAGE_ARG(6);
 	PRINT_IMAGE_ARG(7);
 #endif
 #undef PRINT_IMAGE_ARG
 }

 #ifdef AARCH64
 /*******************************************************************************
  * Handle all possible cases regarding ARMv8.3-PAuth.
  ******************************************************************************/
 void bl_handle_pauth(void)
 {
 #if ENABLE_PAUTH
 	/*
 	 * ENABLE_PAUTH = 1 && CTX_INCLUDE_PAUTH_REGS = 1
 	 *
 	 * Check that the system supports address authentication to avoid
 	 * getting an access fault when accessing the registers. This is all
 	 * that is needed to check. If any of the authentication mechanisms is
 	 * supported, the system knows about ARMv8.3-PAuth, so all the registers
 	 * are available and accessing them won't generate a fault.
 	 *
 	 * Obtain 128-bit instruction key A from the platform and save it to the
 	 * system registers. Pointer authentication can't be enabled here or the
 	 * authentication will fail when returning from this function.
 	 */
 	assert(is_armv8_3_pauth_api_present());

 	uint64_t *apiakey = plat_init_apiakey();

 	write_apiakeylo_el1(apiakey[0]);
 	write_apiakeyhi_el1(apiakey[1]);
 #else /* if !ENABLE_PAUTH */

 # if CTX_INCLUDE_PAUTH_REGS
 	/*
 	 * ENABLE_PAUTH = 0 && CTX_INCLUDE_PAUTH_REGS = 1
 	 *
 	 * Assert that the ARMv8.3-PAuth registers are present or an access
 	 * fault will be triggered when they are being saved or restored.
 	 */
 	assert(is_armv8_3_pauth_present());
 # else
 	/*
 	 * ENABLE_PAUTH = 0 && CTX_INCLUDE_PAUTH_REGS = 0
 	 *
 	 * Pointer authentication is allowed in the Non-secure world, but
 	 * prohibited in the Secure world. The Trusted Firmware doesn't save the
 	 * registers during a world switch. No check needed.
 	 */
 # endif /* CTX_INCLUDE_PAUTH_REGS */

 #endif /* ENABLE_PAUTH */
 }
 #endif /* AARCH64 */
	/*
	* Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
	*
	* SPDX-License-Identifier: BSD-3-Clause
	*/

	#include <assert.h>
	#include <errno.h>
	#include <string.h>

	#include <arch.h>
	#include <arch_features.h>
	#include <arch_helpers.h>
	#include <common/bl_common.h>
	#include <common/debug.h>
	#include <drivers/auth/auth_mod.h>
	#include <drivers/io/io_storage.h>
	#include <lib/utils.h>
	#include <lib/xlat_tables/xlat_tables_defs.h>
	#include <plat/common/platform.h>

	#if TRUSTED_BOARD_BOOT
	# ifdef DYN_DISABLE_AUTH
	static int disable_auth;

	/******************************************************************************
	* API to dynamically disable authentication. Only meant for development
	* systems. This is only invoked if DYN_DISABLE_AUTH is defined.
	*****************************************************************************/
	void dyn_disable_auth(void)
	{
	INFO("Disabling authentication of images dynamically\n");
	disable_auth = 1;
	}
	# endif /* DYN_DISABLE_AUTH */

	/******************************************************************************
	* Function to determine whether the authentication is disabled dynamically.
	*****************************************************************************/
	static int dyn_is_auth_disabled(void)
	{
	# ifdef DYN_DISABLE_AUTH
	return disable_auth;
	# else
	return 0;
	# endif
	}
	#endif /* TRUSTED_BOARD_BOOT */

	uintptr_t page_align(uintptr_t value, unsigned dir)
	{
	/* Round up the limit to the next page boundary */
	if ((value & (PAGE_SIZE - 1U)) != 0U) {
	value &= ~(PAGE_SIZE - 1U);
	if (dir == UP)
	value += PAGE_SIZE;
	}

	return value;
	}

	/*******************************************************************************
	* Internal function to load an image at a specific address given
	* an image ID and extents of free memory.
	*
	* If the load is successful then the image information is updated.
	*
	* Returns 0 on success, a negative error code otherwise.
	******************************************************************************/
	static int load_image(unsigned int image_id, image_info_t *image_data)
	{
	uintptr_t dev_handle;
	uintptr_t image_handle;
	uintptr_t image_spec;
	uintptr_t image_base;
	size_t image_size;
	size_t bytes_read;
	int io_result;

	assert(image_data != NULL);
	assert(image_data->h.version >= VERSION_2);

	image_base = image_data->image_base;

	/* Obtain a reference to the image by querying the platform layer */
	io_result = plat_get_image_source(image_id, &dev_handle, &image_spec);
	if (io_result != 0) {
	WARN("Failed to obtain reference to image id=%u (%i)\n",
	image_id, io_result);
	return io_result;
	}

	/* Attempt to access the image */
	io_result = io_open(dev_handle, image_spec, &image_handle);
	if (io_result != 0) {
	WARN("Failed to access image id=%u (%i)\n",
	image_id, io_result);
	return io_result;
	}

	INFO("Loading image id=%u at address 0x%lx\n", image_id, image_base);

	/* Find the size of the image */
	io_result = io_size(image_handle, &image_size);
	if ((io_result != 0) \|\| (image_size == 0U)) {
	WARN("Failed to determine the size of the image id=%u (%i)\n",
	image_id, io_result);
	goto exit;
	}

	/* Check that the image size to load is within limit */
	if (image_size > image_data->image_max_size) {
	WARN("Image id=%u size out of bounds\n", image_id);
	io_result = -EFBIG;
	goto exit;
	}

	/*
	* image_data->image_max_size is a uint32_t so image_size will always
	* fit in image_data->image_size.
	*/
	image_data->image_size = (uint32_t)image_size;

	/* We have enough space so load the image now */
	/* TODO: Consider whether to try to recover/retry a partially successful read */
	io_result = io_read(image_handle, image_base, image_size, &bytes_read);
	if ((io_result != 0) \|\| (bytes_read < image_size)) {
	WARN("Failed to load image id=%u (%i)\n", image_id, io_result);
	goto exit;
	}

	INFO("Image id=%u loaded: 0x%lx - 0x%lx\n", image_id, image_base,
	(uintptr_t)(image_base + image_size));

	exit:
	(void)io_close(image_handle);
	/* Ignore improbable/unrecoverable error in 'close' */

	/* TODO: Consider maintaining open device connection from this bootloader stage */
	(void)io_dev_close(dev_handle);
	/* Ignore improbable/unrecoverable error in 'dev_close' */

	return io_result;
	}

	static int load_auth_image_internal(unsigned int image_id,
	image_info_t *image_data,
	int is_parent_image)
	{
	int rc;

	#if TRUSTED_BOARD_BOOT
	if (dyn_is_auth_disabled() == 0) {
	unsigned int parent_id;

	/* Use recursion to authenticate parent images */
	rc = auth_mod_get_parent_id(image_id, &parent_id);
	if (rc == 0) {
	rc = load_auth_image_internal(parent_id, image_data, 1);
	if (rc != 0) {
	return rc;
	}
	}
	}
	#endif /* TRUSTED_BOARD_BOOT */

	/* Load the image */
	rc = load_image(image_id, image_data);
	if (rc != 0) {
	return rc;
	}

	#if TRUSTED_BOARD_BOOT
	if (dyn_is_auth_disabled() == 0) {
	/* Authenticate it */
	rc = auth_mod_verify_img(image_id,
	(void *)image_data->image_base,
	image_data->image_size);
	if (rc != 0) {
	/* Authentication error, zero memory and flush it right away. */
	zero_normalmem((void *)image_data->image_base,
	image_data->image_size);
	flush_dcache_range(image_data->image_base,
	image_data->image_size);
	return -EAUTH;
	}
	}
	#endif /* TRUSTED_BOARD_BOOT */

	/*
	* Flush the image to main memory so that it can be executed later by
	* any CPU, regardless of cache and MMU state. If TBB is enabled, then
	* the file has been successfully loaded and authenticated and flush
	* only for child images, not for the parents (certificates).
	*/
	if (is_parent_image == 0) {
	flush_dcache_range(image_data->image_base,
	image_data->image_size);
	}


	return 0;
	}

	/*******************************************************************************
	* Generic function to load and authenticate an image. The image is actually
	* loaded by calling the 'load_image()' function. Therefore, it returns the
	* same error codes if the loading operation failed, or -EAUTH if the
	* authentication failed. In addition, this function uses recursion to
	* authenticate the parent images up to the root of trust.
	******************************************************************************/
	int load_auth_image(unsigned int image_id, image_info_t *image_data)
	{
	int err;

	do {
	err = load_auth_image_internal(image_id, image_data, 0);
	} while ((err != 0) && (plat_try_next_boot_source() != 0));

	return err;
	}

	/*******************************************************************************
	* Print the content of an entry_point_info_t structure.
	******************************************************************************/
	void print_entry_point_info(const entry_point_info_t *ep_info)
	{
	INFO("Entry point address = 0x%lx\n", ep_info->pc);
	INFO("SPSR = 0x%x\n", ep_info->spsr);

	#define PRINT_IMAGE_ARG(n) \
	VERBOSE("Argument #" #n " = 0x%llx\n", \
	(unsigned long long) ep_info->args.arg##n)

	PRINT_IMAGE_ARG(0);
	PRINT_IMAGE_ARG(1);
	PRINT_IMAGE_ARG(2);
	PRINT_IMAGE_ARG(3);
	#ifndef AARCH32
	PRINT_IMAGE_ARG(4);
	PRINT_IMAGE_ARG(5);
	PRINT_IMAGE_ARG(6);
	PRINT_IMAGE_ARG(7);
	#endif
	#undef PRINT_IMAGE_ARG
	}

	#ifdef AARCH64
	/*******************************************************************************
	* Handle all possible cases regarding ARMv8.3-PAuth.
	******************************************************************************/
	void bl_handle_pauth(void)
	{
	#if ENABLE_PAUTH
	/*
	* ENABLE_PAUTH = 1 && CTX_INCLUDE_PAUTH_REGS = 1
	*
	* Check that the system supports address authentication to avoid
	* getting an access fault when accessing the registers. This is all
	* that is needed to check. If any of the authentication mechanisms is
	* supported, the system knows about ARMv8.3-PAuth, so all the registers
	* are available and accessing them won't generate a fault.
	*
	* Obtain 128-bit instruction key A from the platform and save it to the
	* system registers. Pointer authentication can't be enabled here or the
	* authentication will fail when returning from this function.
	*/
	assert(is_armv8_3_pauth_api_present());

	uint64_t *apiakey = plat_init_apiakey();

	write_apiakeylo_el1(apiakey[0]);
	write_apiakeyhi_el1(apiakey[1]);
	#else /* if !ENABLE_PAUTH */

	# if CTX_INCLUDE_PAUTH_REGS
	/*
	* ENABLE_PAUTH = 0 && CTX_INCLUDE_PAUTH_REGS = 1
	*
	* Assert that the ARMv8.3-PAuth registers are present or an access
	* fault will be triggered when they are being saved or restored.
	*/
	assert(is_armv8_3_pauth_present());
	# else
	/*
	* ENABLE_PAUTH = 0 && CTX_INCLUDE_PAUTH_REGS = 0
	*
	* Pointer authentication is allowed in the Non-secure world, but
	* prohibited in the Secure world. The Trusted Firmware doesn't save the
	* registers during a world switch. No check needed.
	*/
	# endif /* CTX_INCLUDE_PAUTH_REGS */

	#endif /* ENABLE_PAUTH */
	}
	#endif /* AARCH64 */