2
* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
4
* SPDX-License-Identifier: GPL-2.0+
9
#include <asm/byteorder.h>
11
enum cbfs_result file_cbfs_result;
13
const char *file_cbfs_error(void)
15
switch (file_cbfs_result) {
18
case CBFS_NOT_INITIALIZED:
19
return "CBFS not initialized";
21
return "Bad CBFS header";
23
return "Bad CBFS file";
24
case CBFS_FILE_NOT_FOUND:
25
return "File not found";
32
static const u32 good_magic = 0x4f524243;
33
static const u8 good_file_magic[] = "LARCHIVE";
36
static int initialized;
37
static struct cbfs_header cbfs_header;
38
static struct cbfs_cachenode *file_cache;
40
/* Do endian conversion on the CBFS header structure. */
41
static void swap_header(struct cbfs_header *dest, struct cbfs_header *src)
43
dest->magic = be32_to_cpu(src->magic);
44
dest->version = be32_to_cpu(src->version);
45
dest->rom_size = be32_to_cpu(src->rom_size);
46
dest->boot_block_size = be32_to_cpu(src->boot_block_size);
47
dest->align = be32_to_cpu(src->align);
48
dest->offset = be32_to_cpu(src->offset);
51
/* Do endian conversion on a CBFS file header. */
52
static void swap_file_header(struct cbfs_fileheader *dest,
53
const struct cbfs_fileheader *src)
55
memcpy(&dest->magic, &src->magic, sizeof(dest->magic));
56
dest->len = be32_to_cpu(src->len);
57
dest->type = be32_to_cpu(src->type);
58
dest->checksum = be32_to_cpu(src->checksum);
59
dest->offset = be32_to_cpu(src->offset);
63
* Given a starting position in memory, scan forward, bounded by a size, and
64
* find the next valid CBFS file. No memory is allocated by this function. The
65
* caller is responsible for allocating space for the new file structure.
67
* @param start The location in memory to start from.
68
* @param size The size of the memory region to search.
69
* @param align The alignment boundaries to check on.
70
* @param newNode A pointer to the file structure to load.
71
* @param used A pointer to the count of of bytes scanned through,
72
* including the file if one is found.
74
* @return 1 if a file is found, 0 if one isn't.
76
static int file_cbfs_next_file(u8 *start, u32 size, u32 align,
77
struct cbfs_cachenode *newNode, u32 *used)
79
struct cbfs_fileheader header;
83
while (size >= align) {
84
const struct cbfs_fileheader *fileHeader =
85
(const struct cbfs_fileheader *)start;
89
/* Check if there's a file here. */
90
if (memcmp(good_file_magic, &(fileHeader->magic),
91
sizeof(fileHeader->magic))) {
98
swap_file_header(&header, fileHeader);
99
if (header.offset < sizeof(const struct cbfs_cachenode *) ||
100
header.offset > header.len) {
101
file_cbfs_result = CBFS_BAD_FILE;
104
newNode->next = NULL;
105
newNode->type = header.type;
106
newNode->data = start + header.offset;
107
newNode->data_length = header.len;
108
name_len = header.offset - sizeof(struct cbfs_cachenode *);
109
newNode->name = (char *)fileHeader +
110
sizeof(struct cbfs_cachenode *);
111
newNode->name_length = name_len;
112
newNode->checksum = header.checksum;
116
step = step + align - step % align;
124
/* Look through a CBFS instance and copy file metadata into regular memory. */
125
static void file_cbfs_fill_cache(u8 *start, u32 size, u32 align)
127
struct cbfs_cachenode *cache_node;
128
struct cbfs_cachenode *newNode;
129
struct cbfs_cachenode **cache_tail = &file_cache;
131
/* Clear out old information. */
132
cache_node = file_cache;
134
struct cbfs_cachenode *oldNode = cache_node;
135
cache_node = cache_node->next;
140
while (size >= align) {
144
newNode = (struct cbfs_cachenode *)
145
malloc(sizeof(struct cbfs_cachenode));
146
result = file_cbfs_next_file(start, size, align,
152
} else if (result == 0) {
156
*cache_tail = newNode;
157
cache_tail = &newNode->next;
162
file_cbfs_result = CBFS_SUCCESS;
165
/* Get the CBFS header out of the ROM and do endian conversion. */
166
static int file_cbfs_load_header(uintptr_t end_of_rom,
167
struct cbfs_header *header)
169
struct cbfs_header *header_in_rom;
171
header_in_rom = (struct cbfs_header *)(uintptr_t)
172
*(u32 *)(end_of_rom - 3);
173
swap_header(header, header_in_rom);
175
if (header->magic != good_magic || header->offset >
176
header->rom_size - header->boot_block_size) {
177
file_cbfs_result = CBFS_BAD_HEADER;
183
void file_cbfs_init(uintptr_t end_of_rom)
188
if (file_cbfs_load_header(end_of_rom, &cbfs_header))
191
start_of_rom = (u8 *)(end_of_rom + 1 - cbfs_header.rom_size);
193
file_cbfs_fill_cache(start_of_rom + cbfs_header.offset,
194
cbfs_header.rom_size, cbfs_header.align);
195
if (file_cbfs_result == CBFS_SUCCESS)
199
const struct cbfs_header *file_cbfs_get_header(void)
202
file_cbfs_result = CBFS_SUCCESS;
205
file_cbfs_result = CBFS_NOT_INITIALIZED;
210
const struct cbfs_cachenode *file_cbfs_get_first(void)
213
file_cbfs_result = CBFS_NOT_INITIALIZED;
216
file_cbfs_result = CBFS_SUCCESS;
221
void file_cbfs_get_next(const struct cbfs_cachenode **file)
224
file_cbfs_result = CBFS_NOT_INITIALIZED;
230
*file = (*file)->next;
231
file_cbfs_result = CBFS_SUCCESS;
234
const struct cbfs_cachenode *file_cbfs_find(const char *name)
236
struct cbfs_cachenode *cache_node = file_cache;
239
file_cbfs_result = CBFS_NOT_INITIALIZED;
244
if (!strcmp(name, cache_node->name))
246
cache_node = cache_node->next;
249
file_cbfs_result = CBFS_FILE_NOT_FOUND;
251
file_cbfs_result = CBFS_SUCCESS;
256
const struct cbfs_cachenode *file_cbfs_find_uncached(uintptr_t end_of_rom,
262
static struct cbfs_cachenode node;
264
if (file_cbfs_load_header(end_of_rom, &cbfs_header))
267
start = (u8 *)(end_of_rom + 1 - cbfs_header.rom_size);
268
size = cbfs_header.rom_size;
269
align = cbfs_header.align;
271
while (size >= align) {
275
result = file_cbfs_next_file(start, size, align, &node, &used);
279
else if (result == 0)
282
if (!strcmp(name, node.name))
288
file_cbfs_result = CBFS_FILE_NOT_FOUND;
292
const char *file_cbfs_name(const struct cbfs_cachenode *file)
294
file_cbfs_result = CBFS_SUCCESS;
298
u32 file_cbfs_size(const struct cbfs_cachenode *file)
300
file_cbfs_result = CBFS_SUCCESS;
301
return file->data_length;
304
u32 file_cbfs_type(const struct cbfs_cachenode *file)
306
file_cbfs_result = CBFS_SUCCESS;
310
long file_cbfs_read(const struct cbfs_cachenode *file, void *buffer,
311
unsigned long maxsize)
315
size = file->data_length;
316
if (maxsize && size > maxsize)
319
memcpy(buffer, file->data, size);
321
file_cbfs_result = CBFS_SUCCESS;