blob: 8850a925f1bc3983ebc8fd442e676894bf9a2ba7 [file] [log] [blame]
/* Copyright 2010, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <assert.h>
#include <fmap.h>
#include <valstr.h>
#include "kv_pair.h"
#include "mincrypt/sha.h"
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
const struct valstr flag_lut[] = {
{ FMAP_AREA_STATIC, "static" },
{ FMAP_AREA_COMPRESSED, "compressed" },
{ FMAP_AREA_RO, "ro" },
};
/* returns size of fmap data structure if successful, <0 to indicate error */
int fmap_size(struct fmap *fmap)
{
if (!fmap)
return -1;
return sizeof(*fmap) + (fmap->nareas * sizeof(struct fmap_area));
}
/* brute force linear search */
static long int fmap_lsearch(const uint8_t *image, size_t len)
{
long int offset;
int fmap_found = 0;
for (offset = 0; offset < len - strlen(FMAP_SIGNATURE); offset++) {
if (!memcmp(&image[offset],
FMAP_SIGNATURE,
strlen(FMAP_SIGNATURE))) {
fmap_found = 1;
break;
}
}
if (!fmap_found)
return -1;
if (offset + fmap_size((struct fmap *)&image[offset]) > len)
return -1;
return offset;
}
/* if image length is a power of 2, use binary search */
static long int fmap_bsearch(const uint8_t *image, size_t len)
{
long int offset = -1;
int fmap_found = 0, stride;
/*
* For efficient operation, we start with the largest stride possible
* and then decrease the stride on each iteration. Also, check for a
* remainder when modding the offset with the previous stride. This
* makes it so that each offset is only checked once.
*/
for (stride = len / 2; stride >= 1; stride /= 2) {
if (fmap_found)
break;
for (offset = 0;
offset < len - strlen(FMAP_SIGNATURE);
offset += stride) {
if ((offset % (stride * 2) == 0) && (offset != 0))
continue;
if (!memcmp(&image[offset],
FMAP_SIGNATURE,
strlen(FMAP_SIGNATURE))) {
fmap_found = 1;
break;
}
}
}
if (!fmap_found)
return -1;
if (offset + fmap_size((struct fmap *)&image[offset]) > len)
return -1;
return offset;
}
static int popcnt(unsigned int u)
{
int count;
/* K&R method */
for (count = 0; u; count++)
u &= (u - 1);
return count;
}
long int fmap_find(const uint8_t *image, unsigned int image_len)
{
long int ret = -1;
if ((image == NULL) || (image_len == 0))
return -1;
if (popcnt(image_len) == 1)
ret = fmap_bsearch(image, image_len);
else
ret = fmap_lsearch(image, image_len);
return ret;
}
int fmap_print(const struct fmap *fmap)
{
int i;
struct kv_pair *kv = NULL;
const uint8_t *tmp;
kv = kv_pair_new();
if (!kv)
return -1;
tmp = fmap->signature;
kv_pair_fmt(kv, "fmap_signature",
"0x%02x%02x%02x%02x%02x%02x%02x%02x",
tmp[0], tmp[1], tmp[2], tmp[3],
tmp[4], tmp[5], tmp[6], tmp[7]);
kv_pair_fmt(kv, "fmap_ver_major", "%d", fmap->ver_major);
kv_pair_fmt(kv, "fmap_ver_minor","%d", fmap->ver_minor);
kv_pair_fmt(kv, "fmap_base", "0x%016llx",
(unsigned long long)fmap->base);
kv_pair_fmt(kv, "fmap_size", "0x%04x", fmap->size);
kv_pair_fmt(kv, "fmap_name", "%s", fmap->name);
kv_pair_fmt(kv, "fmap_nareas", "%d", fmap->nareas);
kv_pair_print(kv);
kv_pair_free(kv);
for (i = 0; i < fmap->nareas; i++) {
struct kv_pair *kv;
uint16_t flags;
char *str;
kv = kv_pair_new();
if (!kv)
return -1;
kv_pair_fmt(kv, "area_offset", "0x%08x",
fmap->areas[i].offset);
kv_pair_fmt(kv, "area_size", "0x%08x",
fmap->areas[i].size);
kv_pair_fmt(kv, "area_name", "%s",
fmap->areas[i].name);
kv_pair_fmt(kv, "area_flags_raw", "0x%02x",
fmap->areas[i].flags);
/* Print descriptive strings for flags rather than the field */
flags = fmap->areas[i].flags;
if ((str = fmap_flags_to_string(flags)) == NULL)
return -1;
kv_pair_fmt(kv, "area_flags", "%s", str );
free(str);
kv_pair_print(kv);
kv_pair_free(kv);
}
return 0;
}
/* get SHA1 sum of all static regions described by the flashmap and copy into
*digest (which will be allocated and must be freed by the caller), */
int fmap_get_csum(const uint8_t *image, unsigned int image_len, uint8_t **digest)
{
int i;
struct fmap *fmap;
int fmap_offset;
SHA_CTX ctx;
if ((image == NULL))
return -1;
if ((fmap_offset = fmap_find(image, image_len)) < 0)
return -1;
fmap = (struct fmap *)(image + fmap_offset);
SHA_init(&ctx);
/* Iterate through flash map and calculate the checksum piece-wise. */
for (i = 0; i < fmap->nareas; i++) {
/* skip non-static areas */
if (!(fmap->areas[i].flags & FMAP_AREA_STATIC))
continue;
/* sanity check the offset */
if (fmap->areas[i].size + fmap->areas[i].offset > image_len) {
fprintf(stderr,
"(%s) invalid parameter detected in area %d\n",
__func__, i);
return -1;
}
SHA_update(&ctx,
image + fmap->areas[i].offset,
fmap->areas[i].size);
}
SHA_final(&ctx);
*digest = malloc(SHA_DIGEST_SIZE);
memcpy(*digest, ctx.buf, SHA_DIGEST_SIZE);
return SHA_DIGEST_SIZE;
}
/* convert raw flags field to user-friendly string */
char *fmap_flags_to_string(uint16_t flags)
{
char *str = NULL;
int i, total_size;
str = malloc(1);
str[0] = '\0';
total_size = 1;
for (i = 0; i < sizeof(flags) * CHAR_BIT; i++) {
if (!flags)
break;
if (flags & (1 << i)) {
const char *tmp = val2str(1 << i, flag_lut);
total_size += strlen(tmp);
str = realloc(str, total_size);
strcat(str, tmp);
flags &= ~(1 << i);
if (flags) {
total_size++;
str = realloc(str, total_size);
strcat(str, ",");
}
}
}
return str;
}
/* allocate and initialize a new fmap structure */
struct fmap *fmap_create(uint64_t base, uint32_t size, uint8_t *name)
{
struct fmap *fmap;
fmap = malloc(sizeof(*fmap));
if (!fmap)
return NULL;
memset(fmap, 0, sizeof(*fmap));
memcpy(&fmap->signature, FMAP_SIGNATURE, strlen(FMAP_SIGNATURE));
fmap->ver_major = VERSION_MAJOR;
fmap->ver_minor = VERSION_MINOR;
fmap->base = base;
fmap->size = size;
memccpy(&fmap->name, name, '\0', FMAP_STRLEN);
return fmap;
}
/* free memory used by an fmap structure */
void fmap_destroy(struct fmap *fmap) {
free(fmap);
}
/* append area to existing structure, return new total size if successful */
int fmap_append_area(struct fmap **fmap,
uint32_t offset, uint32_t size,
const uint8_t *name, uint16_t flags)
{
struct fmap_area *area;
int orig_size, new_size;
if ((fmap == NULL || *fmap == NULL) || (name == NULL))
return -1;
/* too many areas */
if ((*fmap)->nareas >= 0xffff)
return -1;
orig_size = fmap_size(*fmap);
new_size = orig_size + sizeof(*area);
*fmap = realloc(*fmap, new_size);
if (*fmap == NULL)
return -1;
area = (struct fmap_area *)((uint8_t *)*fmap + orig_size);
memset(area, 0, sizeof(*area));
memcpy(&area->offset, &offset, sizeof(area->offset));
memcpy(&area->size, &size, sizeof(area->size));
memccpy(&area->name, name, '\0', FMAP_STRLEN);
memcpy(&area->flags, &flags, sizeof(area->flags));
(*fmap)->nareas++;
return new_size;
}
struct fmap_area *fmap_find_area(struct fmap *fmap, const char *name)
{
int i;
struct fmap_area *area = NULL;
if (!fmap || !name)
return NULL;
for (i = 0; i < fmap->nareas; i++) {
if (!strcmp((const char *)fmap->areas[i].name, name)) {
area = &fmap->areas[i];
break;
}
}
return area;
}
/*
* LCOV_EXCL_START
* Unit testing stuff done here so we do not need to expose static functions.
*/
static enum test_status { pass = EXIT_SUCCESS, fail = EXIT_FAILURE } status;
static struct fmap *fmap_create_test(void)
{
struct fmap *fmap;
uint64_t base = 0;
uint32_t size = 0x100000;
char name[] = "test_fmap";
status = fail;
fmap = fmap_create(base, size, (uint8_t *)name);
if (!fmap)
return NULL;
if (memcmp(&fmap->signature, FMAP_SIGNATURE, strlen(FMAP_SIGNATURE))) {
printf("FAILURE: signature is incorrect\n");
goto fmap_create_test_exit;
}
if ((fmap->ver_major != VERSION_MAJOR) ||
(fmap->ver_minor != VERSION_MINOR)) {
printf("FAILURE: version is incorrect\n");
goto fmap_create_test_exit;
}
if (fmap->base != base) {
printf("FAILURE: base is incorrect\n");
goto fmap_create_test_exit;
}
if (fmap->size != 0x100000) {
printf("FAILURE: size is incorrect\n");
goto fmap_create_test_exit;
}
if (strcmp((char *)fmap->name, "test_fmap")) {
printf("FAILURE: name is incorrect\n");
goto fmap_create_test_exit;
}
if (fmap->nareas != 0) {
printf("FAILURE: number of areas is incorrect\n");
goto fmap_create_test_exit;
}
status = pass;
fmap_create_test_exit:
/* preserve fmap if all went well */
if (status == fail) {
fmap_destroy(fmap);
fmap = NULL;
}
return fmap;
}
static int fmap_print_test(struct fmap *fmap)
{
return fmap_print(fmap);
}
static int fmap_get_csum_test(struct fmap *fmap)
{
uint8_t *digest = NULL, *image = NULL;
/* assume 0x100-0x10100 is marked "static" and is filled with 0x00 */
int image_size = 0x20000;
uint8_t csum[SHA_DIGEST_SIZE] = {
0x1a, 0xdc, 0x95, 0xbe, 0xbe, 0x9e, 0xea, 0x8c,
0x11, 0x2d, 0x40, 0xcd, 0x04, 0xab, 0x7a, 0x8d,
0x75, 0xc4, 0xf9, 0x61 };
status = fail;
if ((fmap_get_csum(NULL, image_size, &digest) >= 0) ||
(fmap_get_csum(image, image_size, NULL) >= 0)) {
printf("failed to abort on NULL pointer input\n");
goto fmap_get_csum_test_exit;
}
image = calloc(image_size, 1);
memcpy(image, fmap, fmap_size(fmap));
if (fmap_get_csum(image, image_size, &digest) != SHA_DIGEST_SIZE) {
printf("FAILURE: failed to calculate checksum\n");
goto fmap_get_csum_test_exit;
}
if (memcmp(digest, csum, SHA_DIGEST_SIZE)) {
printf("FAILURE: checksum is incorrect\n");
goto fmap_get_csum_test_exit;
}
status = pass;
fmap_get_csum_test_exit:
free(image);
free(digest);
return status;
}
static int fmap_size_test(struct fmap *fmap)
{
status = fail;
if (fmap_size(NULL) >= 0) {
printf("FAILURE: failed to abort on NULL pointer input\n");
goto fmap_size_test_exit;
}
status = pass;
fmap_size_test_exit:
return status;
}
/* this test re-allocates the fmap, so it gets a double-pointer */
static int fmap_append_area_test(struct fmap **fmap)
{
int total_size;
uint16_t nareas_orig;
/* test_area will be used by fmap_csum_test and find_area_test */
struct fmap_area test_area = {
.offset = 0x400,
.size = 0x10000,
.name = "test_area_1",
.flags = FMAP_AREA_STATIC,
};
status = fail;
if ((fmap_append_area(NULL, 0, 0, test_area.name, 0) >= 0) ||
(fmap_append_area(fmap, 0, 0, NULL, 0) >= 0)) {
printf("FAILURE: failed to abort on NULL pointer input\n");
goto fmap_append_area_test_exit;
}
nareas_orig = (*fmap)->nareas;
(*fmap)->nareas = ~(0);
if (fmap_append_area(fmap, 0, 0, (const uint8_t *)"foo", 0) >= 0) {
printf("FAILURE: failed to abort with too many areas\n");
goto fmap_append_area_test_exit;
}
(*fmap)->nareas = nareas_orig;
total_size = sizeof(**fmap) + sizeof(test_area);
if (fmap_append_area(fmap,
test_area.offset,
test_area.size,
test_area.name,
test_area.flags
) != total_size) {
printf("failed to append area\n");
goto fmap_append_area_test_exit;
}
if ((*fmap)->nareas != 1) {
printf("FAILURE: failed to increment number of areas\n");
goto fmap_append_area_test_exit;
}
status = pass;
fmap_append_area_test_exit:
return status;
}
static int fmap_find_area_test(struct fmap *fmap)
{
status = fail;
char area_name[] = "test_area_1";
if (fmap_find_area(NULL, area_name) ||
fmap_find_area(fmap, NULL)) {
printf("FAILURE: failed to abort on NULL pointer input\n");
goto fmap_find_area_test_exit;
}
if (fmap_find_area(fmap, area_name) == NULL) {
printf("FAILURE: failed to find \"%s\"\n", area_name);
goto fmap_find_area_test_exit;
}
status = pass;
fmap_find_area_test_exit:
return status;
}
static int fmap_flags_to_string_test()
{
char *str, *my_str;
int i;
uint16_t flags;
status = fail;
/* no area flag */
str = fmap_flags_to_string(0);
if (!str || strcmp(str, "")) {
printf("FAILURE: failed to return empty string when no flag"
"are set");
goto fmap_flags_to_string_test_exit;
}
free(str);
/* single area flags */
for (i = 0; i < ARRAY_SIZE(flag_lut); i++) {
if (!flag_lut[i].str)
continue;
if ((str = fmap_flags_to_string(flag_lut[i].val)) == NULL) {
printf("FAILURE: failed to translate flag to string");
goto fmap_flags_to_string_test_exit;
}
free(str);
}
/* construct our own flags field and string using all available flags
* and compare output with fmap_flags_to_string() */
my_str = calloc(256, 1);
flags = 0;
for (i = 0; i < ARRAY_SIZE(flag_lut); i++) {
if (!flag_lut[i].str)
continue;
else if (i > 0)
strcat(my_str, ",");
flags |= flag_lut[i].val;
strcat(my_str, flag_lut[i].str);
}
str = fmap_flags_to_string(flags);
if (strcmp(str, my_str)) {
printf("FAILURE: bad result from fmap_flags_to_string\n");
goto fmap_flags_to_string_test_exit;
}
free(my_str);
free(str);
status = pass;
fmap_flags_to_string_test_exit:
return status;
}
static int fmap_find_test(struct fmap *fmap)
{
uint8_t *buf;
size_t total_size, offset;
status = fail;
/*
* Note: In these tests, we'll use fmap_find() and control usage of
* lsearch and bsearch by using a power-of-2 total_size. For lsearch,
* use total_size - 1. For bsearch, use total_size.
*/
total_size = 0x100000;
buf = calloc(total_size, 1);
/* test if image length is zero */
if (fmap_find(buf, 0) >= 0) {
printf("FAILURE: failed to abort on zero-length image\n");
goto fmap_find_test_exit;
}
/* test if no fmap exists */
if (fmap_find(buf, total_size - 1) >= 0) {
printf("FAILURE: lsearch returned false positive\n");
goto fmap_find_test_exit;
}
if (fmap_find(buf, total_size) >= 0) {
printf("FAILURE: bsearch returned false positive\n");
goto fmap_find_test_exit;
}
/* simple test case: fmap at (total_size / 2) + 1 */
offset = (total_size / 2) + 1;
memcpy(&buf[offset], fmap, fmap_size(fmap));
if (fmap_find(buf, total_size - 1) != offset) {
printf("FAILURE: lsearch failed to find fmap\n");
goto fmap_find_test_exit;
}
if (fmap_find(buf, total_size) != offset) {
printf("FAILURE: bsearch failed to find fmap\n");
goto fmap_find_test_exit;
}
/* test bsearch if offset is at 0 */
offset = 0;
memset(buf, 0, total_size);
memcpy(buf, fmap, fmap_size(fmap));
if (fmap_find(buf, total_size) != offset) {
printf("FAILURE: bsearch failed to find fmap at offset 0\n");
goto fmap_find_test_exit;
}
/* test overrun detection */
memset(buf, 0, total_size);
memcpy(&buf[total_size - fmap_size(fmap) + 1],
fmap,
fmap_size(fmap) + 1);
if (fmap_find(buf, total_size - 1) >= 0) {
printf("FAILURE: lsearch failed to catch overrun\n");
goto fmap_find_test_exit;
}
if (fmap_find(buf, total_size) >= 0) {
printf("FAILURE: bsearch failed to catch overrun\n");
goto fmap_find_test_exit;
}
status = pass;
fmap_find_test_exit:
free(buf);
return status;
}
int fmap_test()
{
int rc = EXIT_SUCCESS;
struct fmap *my_fmap;
/*
* This test has two parts: Creation of an fmap with one or more
* area(s), and other stuff. Since a valid fmap is required to run
* many tests, we abort if fmap creation fails in any way.
*
* Also, fmap_csum_test() makes some assumptions based on the areas
* appended. See fmap_append_area_test() for details.
*/
if ((my_fmap = fmap_create_test()) == NULL) {
rc = EXIT_FAILURE;
goto fmap_test_exit;
}
if (fmap_find_test(my_fmap)) {
rc = EXIT_FAILURE;
goto fmap_test_exit;
}
if (fmap_append_area_test(&my_fmap)) {
rc = EXIT_FAILURE;
goto fmap_test_exit;
}
rc |= fmap_find_area_test(my_fmap);
rc |= fmap_get_csum_test(my_fmap);
rc |= fmap_size_test(my_fmap);
rc |= fmap_flags_to_string_test();
rc |= fmap_print_test(my_fmap);
fmap_test_exit:
fmap_destroy(my_fmap);
if (rc)
printf("FAILED\n");
return rc;
}
/* LCOV_EXCL_STOP */