fs/cbfs/cbfs.c - u-boot - Git at Google

 /*
  * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
  *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of
  * the License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  * MA 02111-1307 USA
  */

 #include <cbfs.h>
 #include <malloc.h>
 #include <asm/byteorder.h>

 enum cbfs_result file_cbfs_result;

 const char *file_cbfs_error(void)
 {
 	switch (file_cbfs_result) {
 	case CBFS_SUCCESS:
 		return "Success";
 	case CBFS_NOT_INITIALIZED:
 		return "CBFS not initialized";
 	case CBFS_BAD_HEADER:
 		return "Bad CBFS header";
 	case CBFS_BAD_FILE:
 		return "Bad CBFS file";
 	case CBFS_FILE_NOT_FOUND:
 		return "File not found";
 	default:
 		return "Unknown";
 	}
 }


 static const u32 good_magic = 0x4f524243;
 static const u8 good_file_magic[] = "LARCHIVE";


 static int initialized;
 static struct cbfs_header cbfs_header;
 static struct cbfs_cachenode *file_cache;

 /* Do endian conversion on the CBFS header structure. */
 static void swap_header(struct cbfs_header *dest, struct cbfs_header *src)
 {
 	dest->magic = be32_to_cpu(src->magic);
 	dest->version = be32_to_cpu(src->version);
 	dest->rom_size = be32_to_cpu(src->rom_size);
 	dest->boot_block_size = be32_to_cpu(src->boot_block_size);
 	dest->align = be32_to_cpu(src->align);
 	dest->offset = be32_to_cpu(src->offset);
 }

 /* Do endian conversion on a CBFS file header. */
 static void swap_file_header(struct cbfs_fileheader *dest,
 			     const struct cbfs_fileheader *src)
 {
 	memcpy(&dest->magic, &src->magic, sizeof(dest->magic));
 	dest->len = be32_to_cpu(src->len);
 	dest->type = be32_to_cpu(src->type);
 	dest->checksum = be32_to_cpu(src->checksum);
 	dest->offset = be32_to_cpu(src->offset);
 }

 /*
  * Given a starting position in memory, scan forward, bounded by a size, and
  * find the next valid CBFS file. No memory is allocated by this function. The
  * caller is responsible for allocating space for the new file structure.
  *
  * @param start		The location in memory to start from.
  * @param size		The size of the memory region to search.
  * @param align		The alignment boundaries to check on.
  * @param newNode	A pointer to the file structure to load.
  * @param used		A pointer to the count of of bytes scanned through,
  *			including the file if one is found.
  *
  * @return 1 if a file is found, 0 if one isn't.
  */
 static int file_cbfs_next_file(u8 *start, u32 size, u32 align,
 			       struct cbfs_cachenode *newNode, u32 *used)
 {
 	struct cbfs_fileheader header;

 	*used = 0;

 	while (size >= align) {
 		const struct cbfs_fileheader *fileHeader =
 			(const struct cbfs_fileheader *)start;
 		u32 name_len;
 		u32 step;

 		/* Check if there's a file here. */
 		if (memcmp(good_file_magic, &(fileHeader->magic),
 				sizeof(fileHeader->magic))) {
 			*used += align;
 			size -= align;
 			start += align;
 			continue;
 		}

 		swap_file_header(&header, fileHeader);
 		if (header.offset < sizeof(const struct cbfs_cachenode *) ||
 				header.offset > header.len) {
 			file_cbfs_result = CBFS_BAD_FILE;
 			return -1;
 		}
 		newNode->next = NULL;
 		newNode->type = header.type;
 		newNode->data = start + header.offset;
 		newNode->data_length = header.len;
 		name_len = header.offset - sizeof(struct cbfs_cachenode *);
 		newNode->name = (char *)fileHeader +
 				sizeof(struct cbfs_cachenode *);
 		newNode->name_length = name_len;
 		newNode->checksum = header.checksum;

 		step = header.len;
 		if (step % align)
 			step = step + align - step % align;

 		*used += step;
 		return 1;
 	}
 	return 0;
 }

 /* Look through a CBFS instance and copy file metadata into regular memory. */
 static void file_cbfs_fill_cache(u8 *start, u32 size, u32 align)
 {
 	struct cbfs_cachenode *cache_node;
 	struct cbfs_cachenode *newNode;
 	struct cbfs_cachenode **cache_tail = &file_cache;

 	/* Clear out old information. */
 	cache_node = file_cache;
 	while (cache_node) {
 		struct cbfs_cachenode *oldNode = cache_node;
 		cache_node = cache_node->next;
 		free(oldNode);
 	}
 	file_cache = NULL;

 	while (size >= align) {
 		int result;
 		u32 used;

 		newNode = (struct cbfs_cachenode *)
 				malloc(sizeof(struct cbfs_cachenode));
 		result = file_cbfs_next_file(start, size, align,
 			newNode, &used);

 		if (result < 0) {
 			free(newNode);
 			return;
 		} else if (result == 0) {
 			free(newNode);
 			break;
 		}
 		*cache_tail = newNode;
 		cache_tail = &newNode->next;

 		size -= used;
 		start += used;
 	}
 	file_cbfs_result = CBFS_SUCCESS;
 }

 /* Get the CBFS header out of the ROM and do endian conversion. */
 static int file_cbfs_load_header(uintptr_t end_of_rom,
 				 struct cbfs_header *header)
 {
 	struct cbfs_header *header_in_rom;

 	header_in_rom = (struct cbfs_header *)(uintptr_t)
 			*(u32 *)(end_of_rom - 3);
 	swap_header(header, header_in_rom);

 	if (header->magic != good_magic || header->offset >
 			header->rom_size - header->boot_block_size) {
 		file_cbfs_result = CBFS_BAD_HEADER;
 		return 1;
 	}
 	return 0;
 }

 void file_cbfs_init(uintptr_t end_of_rom)
 {
 	u8 *start_of_rom;
 	initialized = 0;

 	if (file_cbfs_load_header(end_of_rom, &cbfs_header))
 		return;

 	start_of_rom = (u8 *)(end_of_rom + 1 - cbfs_header.rom_size);

 	file_cbfs_fill_cache(start_of_rom + cbfs_header.offset,
 			     cbfs_header.rom_size, cbfs_header.align);
 	if (file_cbfs_result == CBFS_SUCCESS)
 		initialized = 1;
 }

 const struct cbfs_header *file_cbfs_get_header(void)
 {
 	if (initialized) {
 		file_cbfs_result = CBFS_SUCCESS;
 		return &cbfs_header;
 	} else {
 		file_cbfs_result = CBFS_NOT_INITIALIZED;
 		return NULL;
 	}
 }

 const struct cbfs_cachenode *file_cbfs_get_first(void)
 {
 	if (!initialized) {
 		file_cbfs_result = CBFS_NOT_INITIALIZED;
 		return NULL;
 	} else {
 		file_cbfs_result = CBFS_SUCCESS;
 		return file_cache;
 	}
 }

 void file_cbfs_get_next(const struct cbfs_cachenode **file)
 {
 	if (!initialized) {
 		file_cbfs_result = CBFS_NOT_INITIALIZED;
 		file = NULL;
 		return;
 	}

 	if (*file)
 		*file = (*file)->next;
 	file_cbfs_result = CBFS_SUCCESS;
 }

 const struct cbfs_cachenode *file_cbfs_find(const char *name)
 {
 	struct cbfs_cachenode *cache_node = file_cache;

 	if (!initialized) {
 		file_cbfs_result = CBFS_NOT_INITIALIZED;
 		return NULL;
 	}

 	while (cache_node) {
 		if (!strcmp(name, cache_node->name))
 			break;
 		cache_node = cache_node->next;
 	}
 	if (!cache_node)
 		file_cbfs_result = CBFS_FILE_NOT_FOUND;
 	else
 		file_cbfs_result = CBFS_SUCCESS;

 	return cache_node;
 }

 const struct cbfs_cachenode *file_cbfs_find_uncached(uintptr_t end_of_rom,
 						     const char *name)
 {
 	u8 *start;
 	u32 size;
 	u32 align;
 	static struct cbfs_cachenode node;

 	if (file_cbfs_load_header(end_of_rom, &cbfs_header))
 		return NULL;

 	start = (u8 *)(end_of_rom + 1 - cbfs_header.rom_size);
 	size = cbfs_header.rom_size;
 	align = cbfs_header.align;

 	while (size >= align) {
 		int result;
 		u32 used;

 		result = file_cbfs_next_file(start, size, align, &node, &used);

 		if (result < 0)
 			return NULL;
 		else if (result == 0)
 			break;

 		if (!strcmp(name, node.name))
 			return &node;

 		size -= used;
 		start += used;
 	}
 	file_cbfs_result = CBFS_FILE_NOT_FOUND;
 	return NULL;
 }

 const char *file_cbfs_name(const struct cbfs_cachenode *file)
 {
 	file_cbfs_result = CBFS_SUCCESS;
 	return file->name;
 }

 u32 file_cbfs_size(const struct cbfs_cachenode *file)
 {
 	file_cbfs_result = CBFS_SUCCESS;
 	return file->data_length;
 }

 u32 file_cbfs_type(const struct cbfs_cachenode *file)
 {
 	file_cbfs_result = CBFS_SUCCESS;
 	return file->type;
 }

 long file_cbfs_read(const struct cbfs_cachenode *file, void *buffer,
 		    unsigned long maxsize)
 {
 	u32 size;

 	size = file->data_length;
 	if (maxsize && size > maxsize)
 		size = maxsize;

 	memcpy(buffer, file->data, size);

 	file_cbfs_result = CBFS_SUCCESS;
 	return size;
 }
	/*
	* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
	*
	* See file CREDITS for list of people who contributed to this
	* project.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 of
	* the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	* MA 02111-1307 USA
	*/

	#include <cbfs.h>
	#include <malloc.h>
	#include <asm/byteorder.h>

	enum cbfs_result file_cbfs_result;

	const char *file_cbfs_error(void)
	{
	switch (file_cbfs_result) {
	case CBFS_SUCCESS:
	return "Success";
	case CBFS_NOT_INITIALIZED:
	return "CBFS not initialized";
	case CBFS_BAD_HEADER:
	return "Bad CBFS header";
	case CBFS_BAD_FILE:
	return "Bad CBFS file";
	case CBFS_FILE_NOT_FOUND:
	return "File not found";
	default:
	return "Unknown";
	}
	}


	static const u32 good_magic = 0x4f524243;
	static const u8 good_file_magic[] = "LARCHIVE";


	static int initialized;
	static struct cbfs_header cbfs_header;
	static struct cbfs_cachenode *file_cache;

	/* Do endian conversion on the CBFS header structure. */
	static void swap_header(struct cbfs_header dest, struct cbfs_header src)
	{
	dest->magic = be32_to_cpu(src->magic);
	dest->version = be32_to_cpu(src->version);
	dest->rom_size = be32_to_cpu(src->rom_size);
	dest->boot_block_size = be32_to_cpu(src->boot_block_size);
	dest->align = be32_to_cpu(src->align);
	dest->offset = be32_to_cpu(src->offset);
	}

	/* Do endian conversion on a CBFS file header. */
	static void swap_file_header(struct cbfs_fileheader *dest,
	const struct cbfs_fileheader *src)
	{
	memcpy(&dest->magic, &src->magic, sizeof(dest->magic));
	dest->len = be32_to_cpu(src->len);
	dest->type = be32_to_cpu(src->type);
	dest->checksum = be32_to_cpu(src->checksum);
	dest->offset = be32_to_cpu(src->offset);
	}

	/*
	* Given a starting position in memory, scan forward, bounded by a size, and
	* find the next valid CBFS file. No memory is allocated by this function. The
	* caller is responsible for allocating space for the new file structure.
	*
	* @param start The location in memory to start from.
	* @param size The size of the memory region to search.
	* @param align The alignment boundaries to check on.
	* @param newNode A pointer to the file structure to load.
	* @param used A pointer to the count of of bytes scanned through,
	* including the file if one is found.
	*
	* @return 1 if a file is found, 0 if one isn't.
	*/
	static int file_cbfs_next_file(u8 *start, u32 size, u32 align,
	struct cbfs_cachenode newNode, u32 used)
	{
	struct cbfs_fileheader header;

	*used = 0;

	while (size >= align) {
	const struct cbfs_fileheader *fileHeader =
	(const struct cbfs_fileheader *)start;
	u32 name_len;
	u32 step;

	/* Check if there's a file here. */
	if (memcmp(good_file_magic, &(fileHeader->magic),
	sizeof(fileHeader->magic))) {
	*used += align;
	size -= align;
	start += align;
	continue;
	}

	swap_file_header(&header, fileHeader);
	if (header.offset < sizeof(const struct cbfs_cachenode *) \|\|
	header.offset > header.len) {
	file_cbfs_result = CBFS_BAD_FILE;
	return -1;
	}
	newNode->next = NULL;
	newNode->type = header.type;
	newNode->data = start + header.offset;
	newNode->data_length = header.len;
	name_len = header.offset - sizeof(struct cbfs_cachenode *);
	newNode->name = (char *)fileHeader +
	sizeof(struct cbfs_cachenode *);
	newNode->name_length = name_len;
	newNode->checksum = header.checksum;

	step = header.len;
	if (step % align)
	step = step + align - step % align;

	*used += step;
	return 1;
	}
	return 0;
	}

	/* Look through a CBFS instance and copy file metadata into regular memory. */
	static void file_cbfs_fill_cache(u8 *start, u32 size, u32 align)
	{
	struct cbfs_cachenode *cache_node;
	struct cbfs_cachenode *newNode;
	struct cbfs_cachenode **cache_tail = &file_cache;

	/* Clear out old information. */
	cache_node = file_cache;
	while (cache_node) {
	struct cbfs_cachenode *oldNode = cache_node;
	cache_node = cache_node->next;
	free(oldNode);
	}
	file_cache = NULL;

	while (size >= align) {
	int result;
	u32 used;

	newNode = (struct cbfs_cachenode *)
	malloc(sizeof(struct cbfs_cachenode));
	result = file_cbfs_next_file(start, size, align,
	newNode, &used);

	if (result < 0) {
	free(newNode);
	return;
	} else if (result == 0) {
	free(newNode);
	break;
	}
	*cache_tail = newNode;
	cache_tail = &newNode->next;

	size -= used;
	start += used;
	}
	file_cbfs_result = CBFS_SUCCESS;
	}

	/* Get the CBFS header out of the ROM and do endian conversion. */
	static int file_cbfs_load_header(uintptr_t end_of_rom,
	struct cbfs_header *header)
	{
	struct cbfs_header *header_in_rom;

	header_in_rom = (struct cbfs_header *)(uintptr_t)
	(u32 )(end_of_rom - 3);
	swap_header(header, header_in_rom);

	if (header->magic != good_magic \|\| header->offset >
	header->rom_size - header->boot_block_size) {
	file_cbfs_result = CBFS_BAD_HEADER;
	return 1;
	}
	return 0;
	}

	void file_cbfs_init(uintptr_t end_of_rom)
	{
	u8 *start_of_rom;
	initialized = 0;

	if (file_cbfs_load_header(end_of_rom, &cbfs_header))
	return;

	start_of_rom = (u8 *)(end_of_rom + 1 - cbfs_header.rom_size);

	file_cbfs_fill_cache(start_of_rom + cbfs_header.offset,
	cbfs_header.rom_size, cbfs_header.align);
	if (file_cbfs_result == CBFS_SUCCESS)
	initialized = 1;
	}

	const struct cbfs_header *file_cbfs_get_header(void)
	{
	if (initialized) {
	file_cbfs_result = CBFS_SUCCESS;
	return &cbfs_header;
	} else {
	file_cbfs_result = CBFS_NOT_INITIALIZED;
	return NULL;
	}
	}

	const struct cbfs_cachenode *file_cbfs_get_first(void)
	{
	if (!initialized) {
	file_cbfs_result = CBFS_NOT_INITIALIZED;
	return NULL;
	} else {
	file_cbfs_result = CBFS_SUCCESS;
	return file_cache;
	}
	}

	void file_cbfs_get_next(const struct cbfs_cachenode **file)
	{
	if (!initialized) {
	file_cbfs_result = CBFS_NOT_INITIALIZED;
	file = NULL;
	return;
	}

	if (*file)
	file = (file)->next;
	file_cbfs_result = CBFS_SUCCESS;
	}

	const struct cbfs_cachenode file_cbfs_find(const char name)
	{
	struct cbfs_cachenode *cache_node = file_cache;

	if (!initialized) {
	file_cbfs_result = CBFS_NOT_INITIALIZED;
	return NULL;
	}

	while (cache_node) {
	if (!strcmp(name, cache_node->name))
	break;
	cache_node = cache_node->next;
	}
	if (!cache_node)
	file_cbfs_result = CBFS_FILE_NOT_FOUND;
	else
	file_cbfs_result = CBFS_SUCCESS;

	return cache_node;
	}

	const struct cbfs_cachenode *file_cbfs_find_uncached(uintptr_t end_of_rom,
	const char *name)
	{
	u8 *start;
	u32 size;
	u32 align;
	static struct cbfs_cachenode node;

	if (file_cbfs_load_header(end_of_rom, &cbfs_header))
	return NULL;

	start = (u8 *)(end_of_rom + 1 - cbfs_header.rom_size);
	size = cbfs_header.rom_size;
	align = cbfs_header.align;

	while (size >= align) {
	int result;
	u32 used;

	result = file_cbfs_next_file(start, size, align, &node, &used);

	if (result < 0)
	return NULL;
	else if (result == 0)
	break;

	if (!strcmp(name, node.name))
	return &node;

	size -= used;
	start += used;
	}
	file_cbfs_result = CBFS_FILE_NOT_FOUND;
	return NULL;
	}

	const char file_cbfs_name(const struct cbfs_cachenode file)
	{
	file_cbfs_result = CBFS_SUCCESS;
	return file->name;
	}

	u32 file_cbfs_size(const struct cbfs_cachenode *file)
	{
	file_cbfs_result = CBFS_SUCCESS;
	return file->data_length;
	}

	u32 file_cbfs_type(const struct cbfs_cachenode *file)
	{
	file_cbfs_result = CBFS_SUCCESS;
	return file->type;
	}

	long file_cbfs_read(const struct cbfs_cachenode file, void buffer,
	unsigned long maxsize)
	{
	u32 size;

	size = file->data_length;
	if (maxsize && size > maxsize)
	size = maxsize;

	memcpy(buffer, file->data, size);

	file_cbfs_result = CBFS_SUCCESS;
	return size;
	}