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/*
* Copyright 2014 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <stdint.h>
#include <stdio.h>
#include "file_type.h"
#include "fmap.h"
#include "futility.h"
#include "traversal.h"
/* What functions do we invoke for a particular operation and component? */
/* FUTIL_OP_SHOW */
static int (* const cb_show_funcs[])(struct futil_traverse_state_s *state) = {
futil_cb_show_begin, /* CB_BEGIN_TRAVERSAL */
NULL, /* CB_END_TRAVERSAL */
futil_cb_show_gbb, /* CB_FMAP_GBB */
futil_cb_show_fw_preamble, /* CB_FMAP_VBLOCK_A */
futil_cb_show_fw_preamble, /* CB_FMAP_VBLOCK_B */
futil_cb_show_fw_main, /* CB_FMAP_FW_MAIN_A */
futil_cb_show_fw_main, /* CB_FMAP_FW_MAIN_B */
futil_cb_show_pubkey, /* CB_PUBKEY */
futil_cb_show_keyblock, /* CB_KEYBLOCK */
futil_cb_show_gbb, /* CB_GBB */
futil_cb_show_fw_preamble, /* CB_FW_PREAMBLE */
futil_cb_show_kernel_preamble, /* CB_KERN_PREAMBLE */
NULL, /* CB_RAW_FIRMWARE */
NULL, /* CB_RAW_KERNEL */
futil_cb_show_privkey, /* CB_PRIVKEY */
};
BUILD_ASSERT(ARRAY_SIZE(cb_show_funcs) == NUM_CB_COMPONENTS);
/* FUTIL_OP_SIGN */
static int (* const cb_sign_funcs[])(struct futil_traverse_state_s *state) = {
futil_cb_sign_begin, /* CB_BEGIN_TRAVERSAL */
futil_cb_sign_end, /* CB_END_TRAVERSAL */
NULL, /* CB_FMAP_GBB */
futil_cb_sign_fw_vblock, /* CB_FMAP_VBLOCK_A */
futil_cb_sign_fw_vblock, /* CB_FMAP_VBLOCK_B */
futil_cb_sign_fw_main, /* CB_FMAP_FW_MAIN_A */
futil_cb_sign_fw_main, /* CB_FMAP_FW_MAIN_B */
futil_cb_sign_pubkey, /* CB_PUBKEY */
NULL, /* CB_KEYBLOCK */
NULL, /* CB_GBB */
NULL, /* CB_FW_PREAMBLE */
futil_cb_resign_kernel_part, /* CB_KERN_PREAMBLE */
futil_cb_sign_raw_firmware, /* CB_RAW_FIRMWARE */
futil_cb_create_kernel_part, /* CB_RAW_KERNEL */
NULL, /* CB_PRIVKEY */
};
BUILD_ASSERT(ARRAY_SIZE(cb_sign_funcs) == NUM_CB_COMPONENTS);
static int (* const * const cb_func[])(struct futil_traverse_state_s *state) = {
cb_show_funcs,
cb_sign_funcs,
};
BUILD_ASSERT(ARRAY_SIZE(cb_func) == NUM_FUTIL_OPS);
/*
* File types that don't need iterating can use a lookup table to determine the
* callback component and name. The index is the file type.
*/
static const struct {
enum futil_cb_component component;
const char * const name;
} direct_callback[] = {
{0, NULL}, /* FILE_TYPE_UNKNOWN */
{CB_PUBKEY, "VbPublicKey"}, /* FILE_TYPE_PUBKEY */
{CB_KEYBLOCK, "VbKeyBlock"}, /* FILE_TYPE_KEYBLOCK */
{CB_FW_PREAMBLE, "FW Preamble"}, /* FILE_TYPE_FW_PREAMBLE */
{CB_GBB, "GBB"}, /* FILE_TYPE_GBB */
{0, NULL}, /* FILE_TYPE_BIOS_IMAGE */
{0, NULL}, /* FILE_TYPE_OLD_BIOS_IMAGE */
{CB_KERN_PREAMBLE, "Kernel Preamble"}, /* FILE_TYPE_KERN_PREAMBLE */
{CB_RAW_FIRMWARE, "raw firmware"}, /* FILE_TYPE_RAW_FIRMWARE */
{CB_RAW_KERNEL, "raw kernel"}, /* FILE_TYPE_RAW_KERNEL */
{0, "chromiumos disk"}, /* FILE_TYPE_CHROMIUMOS_DISK */
{CB_PRIVKEY, "VbPrivateKey"}, /* FILE_TYPE_PRIVKEY */
};
BUILD_ASSERT(ARRAY_SIZE(direct_callback) == NUM_FILE_TYPES);
/*
* The Chrome OS BIOS must contain specific FMAP areas, and we generally want
* to look at each one in a certain order.
*/
struct bios_area_s {
const char * const name;
enum futil_cb_component component;
};
/* This are the expected areas, in order of traversal. */
static const struct bios_area_s bios_area[] = {
{"GBB", CB_FMAP_GBB},
{"FW_MAIN_A", CB_FMAP_FW_MAIN_A},
{"FW_MAIN_B", CB_FMAP_FW_MAIN_B},
{"VBLOCK_A", CB_FMAP_VBLOCK_A},
{"VBLOCK_B", CB_FMAP_VBLOCK_B},
{0, 0}
};
/* Really old BIOS images had different names, but worked the same. */
static const struct bios_area_s old_bios_area[] = {
{"GBB Area", CB_FMAP_GBB},
{"Firmware A Data", CB_FMAP_FW_MAIN_A},
{"Firmware B Data", CB_FMAP_FW_MAIN_B},
{"Firmware A Key", CB_FMAP_VBLOCK_A},
{"Firmware B Key", CB_FMAP_VBLOCK_B},
{0, 0}
};
static int has_all_areas(uint8_t *buf, uint32_t len, FmapHeader *fmap,
const struct bios_area_s *area)
{
/* We must have all the expected areas */
for (; area->name; area++)
if (!fmap_find_by_name(buf, len, fmap, area->name, 0))
return 0;
/* Found 'em all */
return 1;
}
enum futil_file_type recognize_bios_image(uint8_t *buf, uint32_t len)
{
FmapHeader *fmap = fmap_find(buf, len);
if (fmap) {
if (has_all_areas(buf, len, fmap, bios_area))
return FILE_TYPE_BIOS_IMAGE;
if (has_all_areas(buf, len, fmap, old_bios_area))
return FILE_TYPE_OLD_BIOS_IMAGE;
}
return FILE_TYPE_UNKNOWN;
}
static const char * const futil_cb_component_str[] = {
"CB_BEGIN_TRAVERSAL",
"CB_END_TRAVERSAL",
"CB_FMAP_GBB",
"CB_FMAP_VBLOCK_A",
"CB_FMAP_VBLOCK_B",
"CB_FMAP_FW_MAIN_A",
"CB_FMAP_FW_MAIN_B",
"CB_PUBKEY",
"CB_KEYBLOCK",
"CB_GBB",
"CB_FW_PREAMBLE",
"CB_KERN_PREAMBLE",
"CB_RAW_FIRMWARE",
"CB_RAW_KERNEL",
"CB_PRIVKEY",
};
BUILD_ASSERT(ARRAY_SIZE(futil_cb_component_str) == NUM_CB_COMPONENTS);
static int invoke_callback(struct futil_traverse_state_s *state,
enum futil_cb_component c, const char *name,
uint32_t offset, uint8_t *buf, uint32_t len)
{
Debug("%s: name \"%s\" op %d component %s"
" offset=0x%08x len=0x%08x, buf=%p\n",
__func__, name, state->op, futil_cb_component_str[c],
offset, len, buf);
if ((int) c < 0 || c >= NUM_CB_COMPONENTS) {
fprintf(stderr, "Invalid component %d\n", c);
return 1;
}
state->component = c;
state->name = name;
state->cb_area[c].offset = offset;
state->cb_area[c].buf = buf;
state->cb_area[c].len = len;
state->my_area = &state->cb_area[c];
if (cb_func[state->op][c])
return cb_func[state->op][c](state);
return 0;
}
static void fmap_limit_area(FmapAreaHeader *ah, uint32_t len)
{
uint32_t sum = ah->area_offset + ah->area_size;
if (sum < ah->area_size || sum > len) {
Debug("%s(%s) 0x%x + 0x%x > 0x%x\n",
__func__, ah->area_name,
ah->area_offset, ah->area_size, len);
ah->area_offset = 0;
ah->area_size = 0;
}
}
int futil_traverse(uint8_t *buf, uint32_t len,
struct futil_traverse_state_s *state,
enum futil_file_type type)
{
FmapHeader *fmap;
FmapAreaHeader *ah = 0;
const struct bios_area_s *area;
int retval = 0;
if ((int) state->op < 0 || state->op >= NUM_FUTIL_OPS) {
fprintf(stderr, "Invalid op %d\n", state->op);
return 1;
}
if (type == FILE_TYPE_UNKNOWN)
type = futil_file_type_buf(buf, len);
state->in_type = type;
state->errors = retval;
retval |= invoke_callback(state, CB_BEGIN_TRAVERSAL, "<begin>",
0, buf, len);
state->errors = retval;
switch (type) {
case FILE_TYPE_BIOS_IMAGE:
/* We've already checked, so we know this will work. */
fmap = fmap_find(buf, len);
for (area = bios_area; area->name; area++) {
/* We know this will work, too */
fmap_find_by_name(buf, len, fmap, area->name, &ah);
/* But the file might be truncated */
fmap_limit_area(ah, len);
retval |= invoke_callback(state,
area->component,
area->name,
ah->area_offset,
buf + ah->area_offset,
ah->area_size);
state->errors = retval;
}
break;
case FILE_TYPE_OLD_BIOS_IMAGE:
/* We've already checked, so we know this will work. */
fmap = fmap_find(buf, len);
for (area = old_bios_area; area->name; area++) {
/* We know this will work, too */
fmap_find_by_name(buf, len, fmap, area->name, &ah);
/* But the file might be truncated */
fmap_limit_area(ah, len);
retval |= invoke_callback(state,
area->component,
area->name,
ah->area_offset,
buf + ah->area_offset,
ah->area_size);
state->errors = retval;
}
break;
case FILE_TYPE_UNKNOWN:
case FILE_TYPE_CHROMIUMOS_DISK:
/* Nothing to do for these file types (yet) */
break;
default:
/* All other file types have their own callbacks */
retval |= invoke_callback(state,
direct_callback[type].component,
direct_callback[type].name,
0, buf, len);
state->errors = retval;
break;
}
retval |= invoke_callback(state, CB_END_TRAVERSAL, "<end>",
0, buf, len);
return retval;
}