blob: 15d5bdee0ebe809a65dc3f934bbbbbd2b24898f0 [file] [log] [blame]
/*
* Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <arch.h>
#include <arch_helpers.h>
#include <assert.h>
#include <auth_mod.h>
#include <bl_common.h>
#include <debug.h>
#include <errno.h>
#include <io_storage.h>
#include <platform.h>
#include <string.h>
#include <utils.h>
#include <xlat_tables.h>
uintptr_t page_align(uintptr_t value, unsigned dir)
{
/* Round up the limit to the next page boundary */
if (value & (PAGE_SIZE - 1)) {
value &= ~(PAGE_SIZE - 1);
if (dir == UP)
value += PAGE_SIZE;
}
return value;
}
#if !LOAD_IMAGE_V2
/******************************************************************************
* Determine whether the memory region delimited by 'addr' and 'size' is free,
* given the extents of free memory.
* Return 1 if it is free, 0 if it is not free or if the input values are
* invalid.
*****************************************************************************/
static int is_mem_free(uintptr_t free_base, size_t free_size,
uintptr_t addr, size_t size)
{
uintptr_t free_end, requested_end;
/*
* Handle corner cases first.
*
* The order of the 2 tests is important, because if there's no space
* left (i.e. free_size == 0) but we don't ask for any memory
* (i.e. size == 0) then we should report that the memory is free.
*/
if (size == 0)
return 1; /* A zero-byte region is always free */
if (free_size == 0)
return 0;
/*
* Check that the end addresses don't overflow.
* If they do, consider that this memory region is not free, as this
* is an invalid scenario.
*/
if (check_uptr_overflow(free_base, free_size - 1))
return 0;
free_end = free_base + (free_size - 1);
if (check_uptr_overflow(addr, size - 1))
return 0;
requested_end = addr + (size - 1);
/*
* Finally, check that the requested memory region lies within the free
* region.
*/
return (addr >= free_base) && (requested_end <= free_end);
}
/******************************************************************************
* Inside a given memory region, determine whether a sub-region of memory is
* closer from the top or the bottom of the encompassing region. Return the
* size of the smallest chunk of free memory surrounding the sub-region in
* 'small_chunk_size'.
*****************************************************************************/
static unsigned int choose_mem_pos(uintptr_t mem_start, uintptr_t mem_end,
uintptr_t submem_start, uintptr_t submem_end,
size_t *small_chunk_size)
{
size_t top_chunk_size, bottom_chunk_size;
assert(mem_start <= submem_start);
assert(submem_start <= submem_end);
assert(submem_end <= mem_end);
assert(small_chunk_size != NULL);
top_chunk_size = mem_end - submem_end;
bottom_chunk_size = submem_start - mem_start;
if (top_chunk_size < bottom_chunk_size) {
*small_chunk_size = top_chunk_size;
return TOP;
} else {
*small_chunk_size = bottom_chunk_size;
return BOTTOM;
}
}
/******************************************************************************
* Reserve the memory region delimited by 'addr' and 'size'. The extents of free
* memory are passed in 'free_base' and 'free_size' and they will be updated to
* reflect the memory usage.
* The caller must ensure the memory to reserve is free and that the addresses
* and sizes passed in arguments are sane.
*****************************************************************************/
void reserve_mem(uintptr_t *free_base, size_t *free_size,
uintptr_t addr, size_t size)
{
size_t discard_size;
size_t reserved_size;
unsigned int pos;
assert(free_base != NULL);
assert(free_size != NULL);
assert(is_mem_free(*free_base, *free_size, addr, size));
if (size == 0) {
WARN("Nothing to allocate, requested size is zero\n");
return;
}
pos = choose_mem_pos(*free_base, *free_base + (*free_size - 1),
addr, addr + (size - 1),
&discard_size);
reserved_size = size + discard_size;
*free_size -= reserved_size;
if (pos == BOTTOM)
*free_base = addr + size;
VERBOSE("Reserved 0x%zx bytes (discarded 0x%zx bytes %s)\n",
reserved_size, discard_size,
pos == TOP ? "above" : "below");
}
static void dump_load_info(uintptr_t image_load_addr,
size_t image_size,
const meminfo_t *mem_layout)
{
INFO("Trying to load image at address %p, size = 0x%zx\n",
(void *)image_load_addr, image_size);
INFO("Current memory layout:\n");
INFO(" total region = [base = %p, size = 0x%zx]\n",
(void *) mem_layout->total_base, mem_layout->total_size);
INFO(" free region = [base = %p, size = 0x%zx]\n",
(void *) mem_layout->free_base, mem_layout->free_size);
}
#endif /* LOAD_IMAGE_V2 */
/* Generic function to return the size of an image */
size_t image_size(unsigned int image_id)
{
uintptr_t dev_handle;
uintptr_t image_handle;
uintptr_t image_spec;
size_t image_size = 0;
int io_result;
/* 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 0;
}
/* 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 0;
}
/* Find the size of the image */
io_result = io_size(image_handle, &image_size);
if ((io_result != 0) || (image_size == 0)) {
WARN("Failed to determine the size of the image id=%u (%i)\n",
image_id, io_result);
}
io_result = io_close(image_handle);
/* Ignore improbable/unrecoverable error in 'close' */
/* TODO: Consider maintaining open device connection from this
* bootloader stage
*/
io_result = io_dev_close(dev_handle);
/* Ignore improbable/unrecoverable error in 'dev_close' */
return image_size;
}
#if LOAD_IMAGE_V2
/*******************************************************************************
* Generic 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.
******************************************************************************/
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 %p\n", image_id,
(void *) image_base);
/* Find the size of the image */
io_result = io_size(image_handle, &image_size);
if ((io_result != 0) || (image_size == 0)) {
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_size = 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;
}
#if !TRUSTED_BOARD_BOOT
/*
* File has been successfully loaded.
* Flush the image to main memory so that it can be executed later by
* any CPU, regardless of cache and MMU state.
* When TBB is enabled the image is flushed later, after image
* authentication.
*/
flush_dcache_range(image_base, image_size);
#endif /* TRUSTED_BOARD_BOOT */
INFO("Image id=%u loaded: %p - %p\n", image_id, (void *) image_base,
(void *) (image_base + image_size));
exit:
io_close(image_handle);
/* Ignore improbable/unrecoverable error in 'close' */
/* TODO: Consider maintaining open device connection from this bootloader stage */
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
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
/* 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. */
memset((void *)image_data->image_base, 0x00,
image_data->image_size);
flush_dcache_range(image_data->image_base,
image_data->image_size);
return -EAUTH;
}
/*
* File has been successfully loaded and authenticated.
* Flush the image to main memory so that it can be executed later by
* any CPU, regardless of cache and MMU state.
* Do it only for child images, not for the parents (certificates).
*/
if (!is_parent_image) {
flush_dcache_range(image_data->image_base,
image_data->image_size);
}
#endif /* TRUSTED_BOARD_BOOT */
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)
{
return load_auth_image_internal(image_id, image_data, 0);
}
#else /* LOAD_IMAGE_V2 */
/*******************************************************************************
* Generic 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.
*
* If the entry_point_info argument is not NULL then this function also updates:
* - the memory layout to mark the memory as reserved;
* - the entry point information.
*
* The caller might pass a NULL pointer for the entry point if they are not
* interested in this information. This is typically the case for non-executable
* images (e.g. certificates) and executable images that won't ever be executed
* on the application processor (e.g. additional microcontroller firmware).
*
* Returns 0 on success, a negative error code otherwise.
******************************************************************************/
int load_image(meminfo_t *mem_layout,
unsigned int image_id,
uintptr_t image_base,
image_info_t *image_data,
entry_point_info_t *entry_point_info)
{
uintptr_t dev_handle;
uintptr_t image_handle;
uintptr_t image_spec;
size_t image_size;
size_t bytes_read;
int io_result;
assert(mem_layout != NULL);
assert(image_data != NULL);
assert(image_data->h.version == VERSION_1);
/* 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 %p\n", image_id,
(void *) image_base);
/* Find the size of the image */
io_result = io_size(image_handle, &image_size);
if ((io_result != 0) || (image_size == 0)) {
WARN("Failed to determine the size of the image id=%u (%i)\n",
image_id, io_result);
goto exit;
}
/* Check that the memory where the image will be loaded is free */
if (!is_mem_free(mem_layout->free_base, mem_layout->free_size,
image_base, image_size)) {
WARN("Failed to reserve region [base = %p, size = 0x%zx]\n",
(void *) image_base, image_size);
dump_load_info(image_base, image_size, mem_layout);
io_result = -ENOMEM;
goto exit;
}
/* 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;
}
image_data->image_base = image_base;
image_data->image_size = image_size;
/*
* Update the memory usage info.
* This is done after the actual loading so that it is not updated when
* the load is unsuccessful.
* If the caller does not provide an entry point, bypass the memory
* reservation.
*/
if (entry_point_info != NULL) {
reserve_mem(&mem_layout->free_base, &mem_layout->free_size,
image_base, image_size);
entry_point_info->pc = image_base;
} else {
INFO("Skip reserving region [base = %p, size = 0x%zx]\n",
(void *) image_base, image_size);
}
#if !TRUSTED_BOARD_BOOT
/*
* File has been successfully loaded.
* Flush the image to main memory so that it can be executed later by
* any CPU, regardless of cache and MMU state.
* When TBB is enabled the image is flushed later, after image
* authentication.
*/
flush_dcache_range(image_base, image_size);
#endif /* TRUSTED_BOARD_BOOT */
INFO("Image id=%u loaded at address %p, size = 0x%zx\n", image_id,
(void *) image_base, image_size);
exit:
io_close(image_handle);
/* Ignore improbable/unrecoverable error in 'close' */
/* TODO: Consider maintaining open device connection from this bootloader stage */
io_dev_close(dev_handle);
/* Ignore improbable/unrecoverable error in 'dev_close' */
return io_result;
}
static int load_auth_image_internal(meminfo_t *mem_layout,
unsigned int image_id,
uintptr_t image_base,
image_info_t *image_data,
entry_point_info_t *entry_point_info,
int is_parent_image)
{
int rc;
#if TRUSTED_BOARD_BOOT
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(mem_layout, parent_id, image_base,
image_data, NULL, 1);
if (rc != 0) {
return rc;
}
}
#endif /* TRUSTED_BOARD_BOOT */
/* Load the image */
rc = load_image(mem_layout, image_id, image_base, image_data,
entry_point_info);
if (rc != 0) {
return rc;
}
#if TRUSTED_BOARD_BOOT
/* 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. */
memset((void *)image_data->image_base, 0x00,
image_data->image_size);
flush_dcache_range(image_data->image_base,
image_data->image_size);
return -EAUTH;
}
/*
* File has been successfully loaded and authenticated.
* Flush the image to main memory so that it can be executed later by
* any CPU, regardless of cache and MMU state.
* Do it only for child images, not for the parents (certificates).
*/
if (!is_parent_image) {
flush_dcache_range(image_data->image_base,
image_data->image_size);
}
#endif /* TRUSTED_BOARD_BOOT */
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(meminfo_t *mem_layout,
unsigned int image_id,
uintptr_t image_base,
image_info_t *image_data,
entry_point_info_t *entry_point_info)
{
return load_auth_image_internal(mem_layout, image_id, image_base,
image_data, entry_point_info, 0);
}
#endif /* LOAD_IMAGE_V2 */
/*******************************************************************************
* 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 = %p\n", (void *)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
}