Merge "update_verifier: Handle legacy care_map.txt gracefully."

This commit is contained in:
Tao Bao 2017-07-24 16:13:14 +00:00 committed by Gerrit Code Review
commit 15ae0f01c3

View file

@ -175,40 +175,53 @@ static bool read_blocks(const std::string& partition, const std::string& range_s
return true;
}
// Returns true to indicate a passing verification (or the error should be ignored); Otherwise
// returns false on fatal errors, where we should reject the current boot and trigger a fallback.
// Note that update_verifier should be backward compatible to not reject care_map.txt from old
// releases, which could otherwise fail to boot into the new release. For example, we've changed
// the care_map format between N and O. An O update_verifier would fail to work with N
// care_map.txt. This could be a result of sideloading an O OTA while the device having a pending N
// update.
bool verify_image(const std::string& care_map_name) {
android::base::unique_fd care_map_fd(TEMP_FAILURE_RETRY(open(care_map_name.c_str(), O_RDONLY)));
// If the device is flashed before the current boot, it may not have care_map.txt
// in /data/ota_package. To allow the device to continue booting in this situation,
// we should print a warning and skip the block verification.
if (care_map_fd.get() == -1) {
PLOG(WARNING) << "Failed to open " << care_map_name;
return true;
}
// Care map file has four lines (two lines if vendor partition is not present):
// First line has the block partition name (system/vendor).
// Second line holds all ranges of blocks to verify.
// The next two lines have the same format but for vendor partition.
std::string file_content;
if (!android::base::ReadFdToString(care_map_fd.get(), &file_content)) {
LOG(ERROR) << "Error reading care map contents to string.";
return false;
}
std::vector<std::string> lines;
lines = android::base::Split(android::base::Trim(file_content), "\n");
if (lines.size() != 2 && lines.size() != 4) {
LOG(ERROR) << "Invalid lines in care_map: found " << lines.size()
<< " lines, expecting 2 or 4 lines.";
return false;
}
for (size_t i = 0; i < lines.size(); i += 2) {
if (!read_blocks(lines[i], lines[i+1])) {
return false;
}
}
android::base::unique_fd care_map_fd(TEMP_FAILURE_RETRY(open(care_map_name.c_str(), O_RDONLY)));
// If the device is flashed before the current boot, it may not have care_map.txt
// in /data/ota_package. To allow the device to continue booting in this situation,
// we should print a warning and skip the block verification.
if (care_map_fd.get() == -1) {
PLOG(WARNING) << "Failed to open " << care_map_name;
return true;
}
// Care map file has four lines (two lines if vendor partition is not present):
// First line has the block partition name (system/vendor).
// Second line holds all ranges of blocks to verify.
// The next two lines have the same format but for vendor partition.
std::string file_content;
if (!android::base::ReadFdToString(care_map_fd.get(), &file_content)) {
LOG(ERROR) << "Error reading care map contents to string.";
return false;
}
std::vector<std::string> lines;
lines = android::base::Split(android::base::Trim(file_content), "\n");
if (lines.size() != 2 && lines.size() != 4) {
LOG(ERROR) << "Invalid lines in care_map: found " << lines.size()
<< " lines, expecting 2 or 4 lines.";
return false;
}
for (size_t i = 0; i < lines.size(); i += 2) {
// We're seeing an N care_map.txt. Skip the verification since it's not compatible with O
// update_verifier (the last few metadata blocks can't be read via device mapper).
if (android::base::StartsWith(lines[i], "/dev/block/")) {
LOG(WARNING) << "Found legacy care_map.txt; skipped.";
return true;
}
if (!read_blocks(lines[i], lines[i+1])) {
return false;
}
}
return true;
}
static int reboot_device() {