| /* |
| * CBFS Image Manipulation |
| * |
| * Copyright (C) 2013 The Chromium OS Authors. All rights reserved. |
| * |
| * 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; version 2 of the License. |
| * |
| * 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., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "common.h" |
| #include "cbfs_image.h" |
| |
| /* The file name align is not defined in CBFS spec -- only a preference by |
| * (old) cbfstool. */ |
| #define CBFS_FILENAME_ALIGN (16) |
| |
| /* To make CBFS more friendly to ROM, fill -1 (0xFF) instead of zero. */ |
| #define CBFS_CONTENT_DEFAULT_VALUE (-1) |
| |
| static uint32_t align_up(uint32_t value, uint32_t align) { |
| if (value % align) |
| value += align - (value % align); |
| return value; |
| } |
| |
| int cbfs_image_from_file(struct cbfs_image *image, const char *filename) { |
| if (buffer_from_file(&image->buffer, filename) != 0) |
| return -1; |
| DEBUG("read_cbfs_image: %s (%zd bytes)\n", image->buffer.name, |
| image->buffer.size); |
| image->header = cbfs_find_header(image->buffer.data, |
| image->buffer.size); |
| if (!image->header) { |
| ERROR("%s does not have CBFS master header.\n", filename); |
| cbfs_image_delete(image); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| int cbfs_image_write_file(struct cbfs_image *image, const char *filename) { |
| assert(image && image->buffer.data); |
| return buffer_write_file(&image->buffer, filename); |
| } |
| |
| int cbfs_image_delete(struct cbfs_image *image) { |
| buffer_delete(&image->buffer); |
| image->header = NULL; |
| return 0; |
| } |
| |
| struct cbfs_header *cbfs_find_header(char *data, size_t size) { |
| size_t offset; |
| int found = 0; |
| uint32_t x86sig; |
| struct cbfs_header *header, *result = NULL; |
| |
| // Try x86 style (check signature in bottom) header first. |
| x86sig = *(uint32_t *)(data + size - sizeof(uint32_t)); |
| offset = (x86sig + (uint32_t)size); |
| DEBUG("x86sig: 0x%x, offset: 0x%zx\n", x86sig, offset); |
| if (offset >= size - sizeof(*header) || |
| ntohl(((struct cbfs_header *)(data + offset))->magic) != |
| CBFS_HEADER_MAGIC) |
| offset = 0; |
| |
| for (; offset + sizeof(*header) < size; offset++) { |
| header = (struct cbfs_header *)(data + offset); |
| if (ntohl(header->magic) !=(CBFS_HEADER_MAGIC)) |
| continue; |
| if (ntohl(header->version) != CBFS_HEADER_VERSION1 && |
| ntohl(header->version) != CBFS_HEADER_VERSION2) { |
| // Probably not a real CBFS header? |
| continue; |
| } |
| found++; |
| result = header; |
| } |
| if (found > 1) { |
| ERROR("multiple (%d) CBFS headers found!\n", |
| found); |
| result = NULL; |
| } |
| return result; |
| } |
| |
| |
| struct cbfs_file *cbfs_find_first_entry(struct cbfs_image *image) { |
| assert(image && image->header); |
| return (struct cbfs_file *)(image->buffer.data + |
| ntohl(image->header->offset)); |
| } |
| |
| struct cbfs_file *cbfs_find_next_entry(struct cbfs_image *image, |
| struct cbfs_file *entry) { |
| uint32_t addr = cbfs_get_entry_addr(image, entry); |
| int align = ntohl(image->header->align); |
| assert(entry && cbfs_is_valid_entry(entry)); |
| addr += ntohl(entry->offset) + ntohl(entry->len); |
| addr = align_up(addr, align); |
| return (struct cbfs_file *)(image->buffer.data + addr); |
| } |
| |
| uint32_t cbfs_get_entry_addr(struct cbfs_image *image, struct cbfs_file *entry) { |
| assert(image && image->buffer.data && entry); |
| return (int32_t)((char *)entry - image->buffer.data); |
| } |
| |
| int cbfs_is_valid_entry(struct cbfs_file *entry) { |
| return (entry &&memcmp(entry->magic, CBFS_FILE_MAGIC, |
| sizeof(entry->magic)) == 0); |
| } |
| |