| /* |
| * |
| * Copyright (C) 2011 secunet Security Networks AG |
| * Copyright (C) 2013 Google, Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. 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. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. |
| */ |
| |
| /* The CBFS core requires a couple of #defines or functions to adapt it to the |
| * target environment: |
| * |
| * CBFS_CORE_WITH_LZMA (must be #define) |
| * if defined, ulzma() must exist for decompression of data streams |
| * |
| * CBFS_CORE_WITH_LZ4 (must be #define) |
| * if defined, ulz4f() must exist for decompression of data streams |
| * |
| * ERROR(x...) |
| * print an error message x (in printf format) |
| * |
| * LOG(x...) |
| * print a message x (in printf format) |
| * |
| * DEBUG(x...) |
| * print a debug message x (in printf format) |
| * |
| */ |
| |
| #include <libpayload.h> |
| #include <cbfs.h> |
| #include <string.h> |
| #include <sysinfo.h> |
| |
| /* returns a pointer to CBFS master header, or CBFS_HEADER_INVALID_ADDRESS |
| * on failure */ |
| const struct cbfs_header *cbfs_get_header(struct cbfs_media *media) |
| { |
| int32_t rel_offset; |
| const struct cbfs_header *header; |
| struct cbfs_media default_media; |
| |
| if (media == CBFS_DEFAULT_MEDIA) { |
| media = &default_media; |
| if (init_default_cbfs_media(media) != 0) { |
| ERROR("Failed to initialize default media.\n"); |
| return CBFS_HEADER_INVALID_ADDRESS; |
| } |
| } |
| media->open(media); |
| |
| if (!media->read(media, &rel_offset, (size_t)(0 - sizeof(int32_t)), |
| sizeof(int32_t))) { |
| ERROR("Could not read CBFS master header offset!\n"); |
| return CBFS_HEADER_INVALID_ADDRESS; |
| } |
| header = media->map(media, (size_t)rel_offset, sizeof(*header)); |
| DEBUG("CBFS header at %#zx (-%#zx from end of image).\n", |
| (size_t)rel_offset, (size_t)-rel_offset); |
| media->close(media); |
| |
| if (header == CBFS_MEDIA_INVALID_MAP_ADDRESS) { |
| ERROR("Failed to load CBFS header from %#zx(-%#zx)\n", |
| (size_t)rel_offset, (size_t)-rel_offset); |
| return CBFS_HEADER_INVALID_ADDRESS; |
| } |
| |
| if (CBFS_HEADER_MAGIC != ntohl(header->magic)) { |
| ERROR("Could not find valid CBFS master header at %#zx(-%#zx): " |
| "magic %#.8x vs %#.8x.\n", (size_t)rel_offset, |
| (size_t)-rel_offset, CBFS_HEADER_MAGIC, |
| ntohl(header->magic)); |
| if (header->magic == 0xffffffff) { |
| ERROR("Maybe ROM is not mapped properly?\n"); |
| } |
| return CBFS_HEADER_INVALID_ADDRESS; |
| } |
| return header; |
| } |
| |
| static int get_cbfs_range(uint32_t *offset, uint32_t *cbfs_end, |
| struct cbfs_media *media) |
| { |
| const struct cbfs_header *header; |
| |
| if (media == CBFS_DEFAULT_MEDIA && |
| lib_sysinfo.cbfs_offset && lib_sysinfo.cbfs_size) { |
| *offset = lib_sysinfo.cbfs_offset; |
| *cbfs_end = *offset + lib_sysinfo.cbfs_size; |
| return 0; |
| } |
| |
| /* read offset and size from cbfs master header */ |
| DEBUG("Read CBFS offset & size from master header\n"); |
| header = cbfs_get_header(media); |
| if (header == CBFS_HEADER_INVALID_ADDRESS) |
| return -1; |
| // Logical offset (for source media) of first file. |
| *offset = ntohl(header->offset); |
| *cbfs_end = ntohl(header->romsize); |
| #if CONFIG(LP_ARCH_X86) |
| // resolve actual length of ROM used for CBFS components |
| // the bootblock size was not taken into account |
| *cbfs_end -= ntohl(header->bootblocksize); |
| |
| // fine tune the length to handle alignment positioning. |
| // using (bootblock size) % align, to derive the |
| // number of bytes the bootblock is off from the alignment size. |
| if ((ntohl(header->bootblocksize) % CBFS_ALIGNMENT)) |
| *cbfs_end -= (CBFS_ALIGNMENT - |
| (ntohl(header->bootblocksize) % CBFS_ALIGNMENT)); |
| else |
| *cbfs_end -= 1; |
| #endif |
| return 0; |
| } |
| |
| /* public API starts here*/ |
| struct cbfs_handle *cbfs_get_handle(struct cbfs_media *media, const char *name) |
| { |
| const char *vardata; |
| uint32_t offset, cbfs_end, vardata_len; |
| struct cbfs_file file; |
| struct cbfs_handle *handle = malloc(sizeof(*handle)); |
| |
| if (!handle) |
| return NULL; |
| |
| if (get_cbfs_range(&offset, &cbfs_end, media)) { |
| ERROR("Failed to find cbfs range\n"); |
| free(handle); |
| return NULL; |
| } |
| |
| if (media == CBFS_DEFAULT_MEDIA) { |
| media = &handle->media; |
| if (init_default_cbfs_media(media) != 0) { |
| ERROR("Failed to initialize default media.\n"); |
| free(handle); |
| return NULL; |
| } |
| } else { |
| memcpy(&handle->media, media, sizeof(*media)); |
| } |
| |
| DEBUG("CBFS location: 0x%x~0x%x\n", offset, cbfs_end); |
| DEBUG("Looking for '%s' starting from 0x%x.\n", name, offset); |
| |
| media->open(media); |
| while (offset < cbfs_end && |
| media->read(media, &file, offset, sizeof(file)) == sizeof(file)) { |
| if (memcmp(CBFS_FILE_MAGIC, file.magic, |
| sizeof(file.magic)) != 0) { |
| uint32_t new_align = CBFS_ALIGNMENT; |
| if (offset % CBFS_ALIGNMENT) |
| new_align += CBFS_ALIGNMENT - |
| (offset % CBFS_ALIGNMENT); |
| ERROR("ERROR: No file header found at 0x%xx - " |
| "try next aligned address: 0x%x.\n", offset, |
| offset + new_align); |
| offset += new_align; |
| continue; |
| } |
| vardata_len = ntohl(file.offset) - sizeof(file); |
| DEBUG(" - load entry 0x%x variable data (%d bytes)...\n", |
| offset, vardata_len); |
| |
| // load file name (arbitrary length). |
| vardata = (const char*)media->map( |
| media, offset + sizeof(file), vardata_len); |
| if (vardata == CBFS_MEDIA_INVALID_MAP_ADDRESS) { |
| ERROR("ERROR: Failed to get filename: 0x%x.\n", offset); |
| } else if (strcmp(vardata, name) == 0) { |
| int file_offset = ntohl(file.offset), |
| file_len = ntohl(file.len); |
| DEBUG("Found file (offset=0x%x, len=%d).\n", |
| offset + file_offset, file_len); |
| media->unmap(media, vardata); |
| media->close(media); |
| handle->type = ntohl(file.type); |
| handle->media_offset = offset; |
| handle->content_offset = file_offset; |
| handle->content_size = file_len; |
| handle->attribute_offset = |
| ntohl(file.attributes_offset); |
| return handle; |
| } else { |
| DEBUG(" (unmatched file @0x%x: %s)\n", offset, |
| vardata); |
| media->unmap(media, vardata); |
| } |
| |
| // Move to next file. |
| uint32_t next_offset = offset + ntohl(file.len) + ntohl(file.offset); |
| if (next_offset % CBFS_ALIGNMENT) |
| next_offset += CBFS_ALIGNMENT - (next_offset % CBFS_ALIGNMENT); |
| // Check that offset is strictly monotonic to prevent infinite loop |
| if (next_offset <= offset) { |
| ERROR("ERROR: corrupted CBFS file header at 0x%x.\n", offset); |
| break; |
| } |
| offset = next_offset; |
| } |
| media->close(media); |
| LOG("WARNING: '%s' not found.\n", name); |
| free(handle); |
| return NULL; |
| } |
| |
| void *cbfs_get_contents(struct cbfs_handle *handle, size_t *size, size_t limit) |
| { |
| struct cbfs_media *m = &handle->media; |
| size_t on_media_size = handle->content_size; |
| int algo = CBFS_COMPRESS_NONE; |
| void *ret = NULL; |
| size_t dummy_size; |
| |
| if (!size) |
| size = &dummy_size; |
| |
| struct cbfs_file_attr_compression *comp = |
| cbfs_get_attr(handle, CBFS_FILE_ATTR_TAG_COMPRESSION); |
| if (comp) { |
| algo = ntohl(comp->compression); |
| *size = ntohl(comp->decompressed_size); |
| /* TODO: Implement partial decompression with |limit| */ |
| } |
| |
| if (algo == CBFS_COMPRESS_NONE) { |
| if (limit != 0 && limit < on_media_size) |
| on_media_size = limit; |
| *size = on_media_size; |
| } |
| |
| void *data = m->map(m, handle->media_offset + handle->content_offset, |
| on_media_size); |
| if (data == CBFS_MEDIA_INVALID_MAP_ADDRESS) |
| return NULL; |
| |
| ret = malloc(*size); |
| if (ret != NULL) { |
| size_t final_size = cbfs_decompress(algo, data, on_media_size, |
| ret, *size); |
| if (final_size != *size) { |
| ERROR("Expect %zu bytes but got %zu bytes after " |
| "decompression.\n", *size, final_size); |
| free(ret); |
| ret = NULL; |
| } |
| } |
| |
| m->unmap(m, data); |
| return ret; |
| } |
| |
| void *cbfs_get_file_content(struct cbfs_media *media, const char *name, |
| int type, size_t *sz) |
| { |
| void *ret = NULL; |
| struct cbfs_handle *handle = cbfs_get_handle(media, name); |
| |
| if (!handle) |
| return NULL; |
| |
| if (handle->type == type) |
| ret = cbfs_get_contents(handle, sz, 0); |
| else |
| ERROR("File '%s' is of type %x, but we requested %x.\n", name, |
| handle->type, type); |
| |
| free(handle); |
| return ret; |
| } |
| |
| void *cbfs_get_attr(struct cbfs_handle *handle, uint32_t tag) |
| { |
| struct cbfs_media *m = &handle->media; |
| uint32_t offset = handle->media_offset + handle->attribute_offset; |
| uint32_t end = handle->media_offset + handle->content_offset; |
| struct cbfs_file_attribute attr; |
| void *ret; |
| |
| /* attribute_offset should be 0 when there is no attribute, but all |
| * values that point into the cbfs_file header are invalid, too. */ |
| if (handle->attribute_offset <= sizeof(struct cbfs_file)) |
| return NULL; |
| |
| m->open(m); |
| while (offset + sizeof(attr) <= end) { |
| if (m->read(m, &attr, offset, sizeof(attr)) != sizeof(attr)) { |
| ERROR("Failed to read attribute header %#x\n", offset); |
| m->close(m); |
| return NULL; |
| } |
| if (ntohl(attr.tag) != tag) { |
| uint32_t next_offset = offset + ntohl(attr.len); |
| // Check that offset is strictly monotonic to prevent infinite loop |
| if (next_offset <= offset) { |
| ERROR("ERROR: corrupted CBFS attribute at 0x%x.\n", offset); |
| m->close(m); |
| return NULL; |
| } |
| offset = next_offset; |
| continue; |
| } |
| ret = m->map(m, offset, ntohl(attr.len)); |
| if (ret == CBFS_MEDIA_INVALID_MAP_ADDRESS) { |
| ERROR("Failed to map attribute at %#x\n", offset); |
| m->close(m); |
| return NULL; |
| } |
| return ret; |
| } |
| m->close(m); |
| |
| return NULL; |
| } |
| |
| size_t cbfs_decompress(int algo, const void *src, size_t srcn, void *dst, |
| size_t dstn) |
| { |
| size_t len; |
| switch (algo) { |
| case CBFS_COMPRESS_NONE: |
| len = MIN(srcn, dstn); |
| memcpy(dst, src, len); |
| return len; |
| #ifdef CBFS_CORE_WITH_LZMA |
| case CBFS_COMPRESS_LZMA: |
| return ulzman(src, srcn, dst, dstn); |
| #endif |
| #ifdef CBFS_CORE_WITH_LZ4 |
| case CBFS_COMPRESS_LZ4: |
| return ulz4fn(src, srcn, dst, dstn); |
| #endif |
| default: |
| ERROR("tried to decompress %zu bytes with algorithm " |
| "#%x, but that algorithm id is unsupported.\n", |
| srcn, algo); |
| return 0; |
| } |
| } |