static retvalue checkpoolfile(const char *fullfilename, const struct checksums *expected, bool *improveable) {
struct checksums *actual;
retvalue r;
bool improves;
r = checksums_read(fullfilename, &actual);
if (RET_IS_OK(r)) {
if (!checksums_check(expected, actual, &improves)) {
fprintf(stderr, "WRONG CHECKSUMS of '%s':\n",
fullfilename);
checksums_printdifferences(stderr, expected, actual);
r = RET_ERROR_WRONG_MD5;
} else if (improves)
*improveable = true;
checksums_free(actual);
}
return r;
}
retvalue files_detect(const char *filekey) {
struct checksums *checksums;
char *fullfilename;
retvalue r;
fullfilename = files_calcfullfilename(filekey);
if (FAILEDTOALLOC(fullfilename))
return RET_ERROR_OOM;
r = checksums_read(fullfilename, &checksums);
if (r == RET_NOTHING) {
fprintf(stderr, "Error opening '%s'!\n", fullfilename);
r = RET_ERROR_MISSING;
}
if (RET_WAS_ERROR(r)) {
free(fullfilename);
return r;
}
free(fullfilename);
r = files_add_checksums(filekey, checksums);
checksums_free(checksums);
return r;
}
/*!
* \brief Set the kernel for a ROM
*
* \note This will update the checksum for the image in
* \a /data/multiboot/checksums.prop.
*
* \param id ROM ID to set the kernel for
* \param boot_blockdev Block device path of the boot partition
*
* \return True if the kernel was successfully set. Otherwise, false.
*/
bool set_kernel(const char *id, const char *boot_blockdev)
{
LOGD("Attempting to set the kernel for %s", id);
// Path for all of the images
std::string multiboot_path(get_raw_path(MULTIBOOT_DIR));
multiboot_path += "/";
multiboot_path += id;
std::string bootimg_path(multiboot_path);
bootimg_path += "/boot.img";
// Verify ROM ID
Roms roms;
roms.add_installed();
auto r = roms.find_by_id(id);
if (!r) {
LOGE("Invalid ROM ID: %s", id);
return false;
}
if (!util::mkdir_recursive(multiboot_path, 0775)) {
LOGE("%s: Failed to create directory: %s",
multiboot_path.c_str(), strerror(errno));
return false;
}
unsigned char *data;
std::size_t size;
if (!util::file_read_all(boot_blockdev, &data, &size)) {
LOGE("%s: Failed to read block device: %s",
boot_blockdev, strerror(errno));
return false;
}
auto free_data = util::finally([&]{
free(data);
});
// Get actual sha512sum
unsigned char digest[SHA512_DIGEST_LENGTH];
SHA512(data, size, digest);
std::string hash = util::hex_string(digest, SHA512_DIGEST_LENGTH);
// Add to checksums.prop
std::unordered_map<std::string, std::string> props;
checksums_read(&props);
checksums_update(&props, id, "boot.img", hash);
// NOTE: This function isn't responsible for updating the checksums for
// any extra images. We don't want to mask any malicious changes.
// Cast is okay. The data is just passed to fwrite (ie. no signed
// extension issues)
if (!util::file_write_data(bootimg_path, (char *) data, size)) {
LOGE("%s: Failed to write image: %s",
bootimg_path.c_str(), strerror(errno));
return false;
}
LOGD("Updating checksums file");
checksums_write(props);
if (!fix_multiboot_permissions()) {
//return false;
}
return true;
}
/*!
* \brief Switch to another ROM
*
* \note If the checksum is missing for some images to be flashed and invalid
* for some other images to be flashed, this function will always return
* SwitchRomResult::CHECKSUM_INVALID.
*
* \param id ROM ID to switch to
* \param boot_blockdev Block device path of the boot partition
* \param blockdev_base_dirs Search paths (non-recursive) for block devices
* corresponding to extra flashable images in
* /sdcard/MultiBoot/[ROM ID]/ *.img
*
* \return SwitchRomResult::SUCCEEDED if the switching succeeded,
* SwitchRomResult::FAILED if the switching failed,
* SwitchRomResult::CHECKSUM_NOT_FOUND if the checksum for some image is missing,
* SwitchRomResult::CHECKSUM_INVALID if the checksum for some image is invalid
*
*/
SwitchRomResult switch_rom(const char *id, const char *boot_blockdev,
const char * const *blockdev_base_dirs,
bool force_update_checksums)
{
LOGD("Attempting to switch to %s", id);
LOGD("Force update checksums: %d", force_update_checksums);
// Path for all of the images
std::string multiboot_path(get_raw_path(MULTIBOOT_DIR));
multiboot_path += "/";
multiboot_path += id;
std::string bootimg_path(multiboot_path);
bootimg_path += "/boot.img";
// Verify ROM ID
Roms roms;
roms.add_installed();
auto r = roms.find_by_id(id);
if (!r) {
LOGE("Invalid ROM ID: %s", id);
return SwitchRomResult::FAILED;
}
if (!util::mkdir_recursive(multiboot_path, 0775)) {
LOGE("%s: Failed to create directory: %s",
multiboot_path.c_str(), strerror(errno));
return SwitchRomResult::FAILED;
}
// We'll read the files we want to flash into memory so a malicious app
// can't change the file between the hash verification step and flashing
// step.
std::vector<Flashable> flashables;
auto free_flashables = util::finally([&]{
for (Flashable &f : flashables) {
free(f.data);
}
});
flashables.emplace_back();
flashables.back().image = bootimg_path;
flashables.back().block_dev = boot_blockdev;
if (!add_extra_images(multiboot_path.c_str(), blockdev_base_dirs, &flashables)) {
LOGW("Failed to find extra images");
}
std::unordered_map<std::string, std::string> props;
checksums_read(&props);
for (Flashable &f : flashables) {
// If memory becomes an issue, an alternative method is to create a
// temporary directory in /data/multiboot/ that's only writable by root
// and copy the images there.
if (!util::file_read_all(f.image, &f.data, &f.size)) {
LOGE("%s: Failed to read image: %s",
f.image.c_str(), strerror(errno));
return SwitchRomResult::FAILED;
}
// Get actual sha512sum
unsigned char digest[SHA512_DIGEST_LENGTH];
SHA512(f.data, f.size, digest);
f.hash = util::hex_string(digest, SHA512_DIGEST_LENGTH);
if (force_update_checksums) {
checksums_update(&props, id, util::base_name(f.image), f.hash);
}
// Get expected sha512sum
ChecksumsGetResult ret = checksums_get(
&props, id, util::base_name(f.image), &f.expected_hash);
if (ret == ChecksumsGetResult::MALFORMED) {
return SwitchRomResult::CHECKSUM_INVALID;
}
// Verify hashes if we have an expected hash
if (ret == ChecksumsGetResult::FOUND && f.expected_hash != f.hash) {
LOGE("%s: Checksum (%s) does not match expected (%s)",
f.image.c_str(), f.hash.c_str(), f.expected_hash.c_str());
return SwitchRomResult::CHECKSUM_INVALID;
}
}
// Fail if we're missing expected hashes. We do this last to make sure
// CHECKSUM_INVALID is returned if some checksums don't match (for the ones
// that aren't missing).
for (Flashable &f : flashables) {
if (f.expected_hash.empty()) {
LOGE("%s: Checksum does not exist", f.image.c_str());
return SwitchRomResult::CHECKSUM_NOT_FOUND;
}
}
// Now we can flash the images
for (Flashable &f : flashables) {
// Cast is okay. The data is just passed to fwrite (ie. no signed
// extension issues)
if (!util::file_write_data(f.block_dev, (char *) f.data, f.size)) {
LOGE("%s: Failed to write image: %s",
f.block_dev.c_str(), strerror(errno));
return SwitchRomResult::FAILED;
}
}
if (force_update_checksums) {
LOGD("Updating checksums file");
checksums_write(props);
}
if (!fix_multiboot_permissions()) {
//return SwitchRomResult::FAILED;
}
return SwitchRomResult::SUCCEEDED;
}
static retvalue checkimproveorinclude(const char *sourcedir, const char *basefilename, const char *filekey, struct checksums **checksums_p, bool *improving) {
retvalue r;
struct checksums *checksums = NULL;
bool improves, copied = false;
char *fullfilename = files_calcfullfilename(filekey);
if (FAILEDTOALLOC(fullfilename))
return RET_ERROR_OOM;
if (checksums_iscomplete(*checksums_p)) {
r = checksums_cheaptest(fullfilename, *checksums_p, true);
if (r != RET_NOTHING) {
free(fullfilename);
return r;
}
} else {
r = checksums_read(fullfilename, &checksums);
if (RET_WAS_ERROR(r)) {
free(fullfilename);
return r;
}
}
if (r == RET_NOTHING) {
char *sourcefilename = calc_dirconcat(sourcedir, basefilename);
if (FAILEDTOALLOC(sourcefilename)) {
free(fullfilename);
return RET_ERROR_OOM;
}
fprintf(stderr,
"WARNING: file %s was lost!\n"
"(i.e. found in the database, but not in the pool)\n"
"trying to compensate...\n",
filekey);
(void)dirs_make_parent(fullfilename);
r = checksums_copyfile(fullfilename, sourcefilename, false,
&checksums);
if (r == RET_ERROR_EXIST) {
fprintf(stderr,
"File '%s' seems to be missing and existing at the same time!\n"
"To confused to continue...\n",
fullfilename);
}
if (r == RET_NOTHING) {
fprintf(stderr, "Could not open '%s'!\n",
sourcefilename);
r = RET_ERROR_MISSING;
}
free(sourcefilename);
if (RET_WAS_ERROR(r)) {
free(fullfilename);
return r;
}
copied = true;
}
assert (checksums != NULL);
if (!checksums_check(*checksums_p, checksums, &improves)) {
if (copied) {
deletefile(fullfilename);
fprintf(stderr,
"ERROR: Unexpected content of file '%s/%s'!\n", sourcedir, basefilename);
} else
// TODO: if the database only listed some of the currently supported checksums,
// and the caller of checkincludefile supplied some (which none yet does), but
// not all (which needs at least three checksums, i.e. not applicaple before
// sha256 get added), then this might also be called if the file in the pool
// just has the same checksums as previously recorded (e.g. a md5sum collision)
// but the new file was listed with another secondary hash than the original.
// In that situation it might be a bit misleading...
fprintf(stderr,
"ERROR: file %s is damaged!\n"
"(i.e. found in the database, but with different checksums in the pool)\n",
filekey);
checksums_printdifferences(stderr, *checksums_p, checksums);
r = RET_ERROR_WRONG_MD5;
}
if (improves) {
r = checksums_combine(checksums_p, checksums, NULL);
if (RET_IS_OK(r))
*improving = true;
}
checksums_free(checksums);
free(fullfilename);
return r;
}
/* Include a yet unknown file into the pool */
retvalue files_preinclude(const char *sourcefilename, const char *filekey, struct checksums **checksums_p) {
retvalue r;
struct checksums *checksums, *realchecksums;
bool improves;
char *fullfilename;
r = files_get_checksums(filekey, &checksums);
if (RET_WAS_ERROR(r))
return r;
if (RET_IS_OK(r)) {
r = checksums_read(sourcefilename, &realchecksums);
if (r == RET_NOTHING)
r = RET_ERROR_MISSING;
if (RET_WAS_ERROR(r)) {
checksums_free(checksums);
return r;
}
if (!checksums_check(checksums, realchecksums, &improves)) {
fprintf(stderr,
"ERROR: '%s' cannot be included as '%s'.\n"
"Already existing files can only be included again, if they are the same, but:\n",
sourcefilename, filekey);
checksums_printdifferences(stderr, checksums,
realchecksums);
checksums_free(checksums);
checksums_free(realchecksums);
return RET_ERROR_WRONG_MD5;
}
if (improves) {
r = checksums_combine(&checksums, realchecksums, NULL);
if (RET_WAS_ERROR(r)) {
checksums_free(realchecksums);
checksums_free(checksums);
return r;
}
r = files_replace_checksums(filekey, checksums);
if (RET_WAS_ERROR(r)) {
checksums_free(realchecksums);
checksums_free(checksums);
return r;
}
}
checksums_free(realchecksums);
// args, this breaks retvalue semantics!
if (checksums_p != NULL)
*checksums_p = checksums;
else
checksums_free(checksums);
return RET_NOTHING;
}
assert (sourcefilename != NULL);
fullfilename = files_calcfullfilename(filekey);
if (FAILEDTOALLOC(fullfilename))
return RET_ERROR_OOM;
(void)dirs_make_parent(fullfilename);
r = checksums_copyfile(fullfilename, sourcefilename, true, &checksums);
if (r == RET_ERROR_EXIST) {
// TODO: deal with already existing files!
fprintf(stderr, "File '%s' does already exist!\n",
fullfilename);
}
if (r == RET_NOTHING) {
fprintf(stderr, "Could not open '%s'!\n", sourcefilename);
r = RET_ERROR_MISSING;
}
if (RET_WAS_ERROR(r)) {
free(fullfilename);
return r;
}
free(fullfilename);
r = files_add_checksums(filekey, checksums);
if (RET_WAS_ERROR(r)) {
checksums_free(checksums);
return r;
}
if (checksums_p != NULL)
*checksums_p = checksums;
else
checksums_free(checksums);
return RET_OK;
}
