| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Copyright (c) 2011 The Chromium OS Authors. All rights reserved. |
| */ |
| |
| #include <common.h> |
| #include <cbfs.h> |
| #include <malloc.h> |
| #include <asm/byteorder.h> |
| |
| static const u32 good_magic = 0x4f524243; |
| static const u8 good_file_magic[] = "LARCHIVE"; |
| |
| struct cbfs_priv { |
| bool initialized; |
| struct cbfs_header header; |
| struct cbfs_cachenode *file_cache; |
| enum cbfs_result result; |
| }; |
| |
| static struct cbfs_priv cbfs_s; |
| |
| const char *file_cbfs_error(void) |
| { |
| switch (cbfs_s.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"; |
| } |
| } |
| |
| enum cbfs_result cbfs_get_result(void) |
| { |
| return cbfs_s.result; |
| } |
| |
| /* 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->attributes_offset = be32_to_cpu(src->attributes_offset); |
| 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 new_node 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 0 if a file is found, -ENOENT if one isn't, -EBADF if a bad header |
| * is found. |
| */ |
| static int file_cbfs_next_file(struct cbfs_priv *priv, u8 *start, int size, |
| int align, struct cbfs_cachenode *new_node, |
| int *used) |
| { |
| struct cbfs_fileheader header; |
| |
| *used = 0; |
| |
| while (size >= align) { |
| const struct cbfs_fileheader *file_header = |
| (const struct cbfs_fileheader *)start; |
| u32 name_len; |
| u32 step; |
| |
| /* Check if there's a file here. */ |
| if (memcmp(good_file_magic, &file_header->magic, |
| sizeof(file_header->magic))) { |
| *used += align; |
| size -= align; |
| start += align; |
| continue; |
| } |
| |
| swap_file_header(&header, file_header); |
| if (header.offset < sizeof(struct cbfs_fileheader)) { |
| priv->result = CBFS_BAD_FILE; |
| return -EBADF; |
| } |
| new_node->next = NULL; |
| new_node->type = header.type; |
| new_node->data = start + header.offset; |
| new_node->data_length = header.len; |
| name_len = header.offset - sizeof(struct cbfs_fileheader); |
| new_node->name = (char *)file_header + |
| sizeof(struct cbfs_fileheader); |
| new_node->name_length = name_len; |
| new_node->attributes_offset = header.attributes_offset; |
| |
| step = header.len; |
| if (step % align) |
| step = step + align - step % align; |
| |
| *used += step; |
| return 0; |
| } |
| |
| return -ENOENT; |
| } |
| |
| /* Look through a CBFS instance and copy file metadata into regular memory. */ |
| static int file_cbfs_fill_cache(struct cbfs_priv *priv, u8 *start, u32 size, |
| u32 align) |
| { |
| struct cbfs_cachenode *cache_node; |
| struct cbfs_cachenode *new_node; |
| struct cbfs_cachenode **cache_tail = &priv->file_cache; |
| |
| /* Clear out old information. */ |
| cache_node = priv->file_cache; |
| while (cache_node) { |
| struct cbfs_cachenode *old_node = cache_node; |
| cache_node = cache_node->next; |
| free(old_node); |
| } |
| priv->file_cache = NULL; |
| |
| while (size >= align) { |
| int used; |
| int ret; |
| |
| new_node = (struct cbfs_cachenode *) |
| malloc(sizeof(struct cbfs_cachenode)); |
| if (!new_node) |
| return -ENOMEM; |
| ret = file_cbfs_next_file(priv, start, size, align, new_node, |
| &used); |
| |
| if (ret < 0) { |
| free(new_node); |
| if (ret == -ENOENT) |
| break; |
| return ret; |
| } |
| *cache_tail = new_node; |
| cache_tail = &new_node->next; |
| |
| size -= used; |
| start += used; |
| } |
| priv->result = CBFS_SUCCESS; |
| |
| return 0; |
| } |
| |
| /* Get the CBFS header out of the ROM and do endian conversion. */ |
| static int file_cbfs_load_header(struct cbfs_priv *priv, ulong end_of_rom) |
| { |
| struct cbfs_header *header = &priv->header; |
| struct cbfs_header *header_in_rom; |
| int32_t offset = *(u32 *)(end_of_rom - 3); |
| |
| header_in_rom = (struct cbfs_header *)(end_of_rom + offset + 1); |
| swap_header(header, header_in_rom); |
| |
| if (header->magic != good_magic || header->offset > |
| header->rom_size - header->boot_block_size) { |
| priv->result = CBFS_BAD_HEADER; |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int cbfs_load_header_ptr(struct cbfs_priv *priv, ulong base, |
| struct cbfs_header *header) |
| { |
| struct cbfs_header *header_in_rom; |
| |
| header_in_rom = (struct cbfs_header *)base; |
| swap_header(header, header_in_rom); |
| |
| if (header->magic != good_magic || header->offset > |
| header->rom_size - header->boot_block_size) { |
| priv->result = CBFS_BAD_HEADER; |
| return -EFAULT; |
| } |
| |
| return 0; |
| } |
| |
| static void cbfs_init(struct cbfs_priv *priv, ulong end_of_rom) |
| { |
| u8 *start_of_rom; |
| |
| priv->initialized = false; |
| |
| if (file_cbfs_load_header(priv, end_of_rom)) |
| return; |
| |
| start_of_rom = (u8 *)(end_of_rom + 1 - priv->header.rom_size); |
| |
| file_cbfs_fill_cache(priv, start_of_rom, priv->header.rom_size, |
| priv->header.align); |
| if (priv->result == CBFS_SUCCESS) |
| priv->initialized = true; |
| } |
| |
| void file_cbfs_init(ulong end_of_rom) |
| { |
| cbfs_init(&cbfs_s, end_of_rom); |
| } |
| |
| int cbfs_init_mem(ulong base, ulong size, struct cbfs_priv **privp) |
| { |
| struct cbfs_priv priv_s, *priv = &priv_s; |
| int ret; |
| |
| /* |
| * Use a local variable to start with until we know that the CBFS is |
| * valid. Assume that a master header appears at the start, at offset |
| * 0x38. |
| */ |
| ret = cbfs_load_header_ptr(priv, base + 0x38, &priv->header); |
| if (ret) |
| return ret; |
| |
| file_cbfs_fill_cache(priv, (u8 *)base, priv->header.rom_size, |
| priv->header.align); |
| if (priv->result != CBFS_SUCCESS) |
| return -EINVAL; |
| |
| priv->initialized = true; |
| priv = malloc(sizeof(priv_s)); |
| if (!priv) |
| return -ENOMEM; |
| memcpy(priv, &priv_s, sizeof(priv_s)); |
| *privp = priv; |
| |
| return 0; |
| } |
| |
| const struct cbfs_header *file_cbfs_get_header(void) |
| { |
| struct cbfs_priv *priv = &cbfs_s; |
| |
| if (priv->initialized) { |
| priv->result = CBFS_SUCCESS; |
| return &priv->header; |
| } else { |
| priv->result = CBFS_NOT_INITIALIZED; |
| return NULL; |
| } |
| } |
| |
| const struct cbfs_cachenode *file_cbfs_get_first(void) |
| { |
| struct cbfs_priv *priv = &cbfs_s; |
| |
| if (!priv->initialized) { |
| priv->result = CBFS_NOT_INITIALIZED; |
| return NULL; |
| } else { |
| priv->result = CBFS_SUCCESS; |
| return priv->file_cache; |
| } |
| } |
| |
| void file_cbfs_get_next(const struct cbfs_cachenode **file) |
| { |
| struct cbfs_priv *priv = &cbfs_s; |
| |
| if (!priv->initialized) { |
| priv->result = CBFS_NOT_INITIALIZED; |
| *file = NULL; |
| return; |
| } |
| |
| if (*file) |
| *file = (*file)->next; |
| priv->result = CBFS_SUCCESS; |
| } |
| |
| const struct cbfs_cachenode *cbfs_find_file(struct cbfs_priv *priv, |
| const char *name) |
| { |
| struct cbfs_cachenode *cache_node = priv->file_cache; |
| |
| if (!priv->initialized) { |
| priv->result = CBFS_NOT_INITIALIZED; |
| return NULL; |
| } |
| |
| while (cache_node) { |
| if (!strcmp(name, cache_node->name)) |
| break; |
| cache_node = cache_node->next; |
| } |
| if (!cache_node) |
| priv->result = CBFS_FILE_NOT_FOUND; |
| else |
| priv->result = CBFS_SUCCESS; |
| |
| return cache_node; |
| } |
| |
| const struct cbfs_cachenode *file_cbfs_find(const char *name) |
| { |
| return cbfs_find_file(&cbfs_s, name); |
| } |
| |
| const struct cbfs_cachenode *file_cbfs_find_uncached(ulong end_of_rom, |
| const char *name) |
| { |
| struct cbfs_priv *priv = &cbfs_s; |
| u8 *start; |
| u32 size; |
| u32 align; |
| static struct cbfs_cachenode node; |
| |
| if (file_cbfs_load_header(priv, end_of_rom)) |
| return NULL; |
| |
| start = (u8 *)(end_of_rom + 1 - priv->header.rom_size); |
| size = priv->header.rom_size; |
| align = priv->header.align; |
| |
| while (size >= align) { |
| int ret; |
| int used; |
| |
| ret = file_cbfs_next_file(priv, start, size, align, &node, |
| &used); |
| if (ret == -ENOENT) |
| break; |
| else if (ret) |
| return NULL; |
| if (!strcmp(name, node.name)) |
| return &node; |
| |
| size -= used; |
| start += used; |
| } |
| cbfs_s.result = CBFS_FILE_NOT_FOUND; |
| return NULL; |
| } |
| |
| const char *file_cbfs_name(const struct cbfs_cachenode *file) |
| { |
| cbfs_s.result = CBFS_SUCCESS; |
| |
| return file->name; |
| } |
| |
| u32 file_cbfs_size(const struct cbfs_cachenode *file) |
| { |
| cbfs_s.result = CBFS_SUCCESS; |
| |
| return file->data_length; |
| } |
| |
| u32 file_cbfs_type(const struct cbfs_cachenode *file) |
| { |
| cbfs_s.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); |
| cbfs_s.result = CBFS_SUCCESS; |
| |
| return size; |
| } |