Merge "first stage mount: removing the requirement of by-name prefix for AVB"

This commit is contained in:
Treehugger Robot 2017-05-10 01:37:26 +00:00 committed by Gerrit Code Review
commit cdad92fdad
6 changed files with 188 additions and 133 deletions

View File

@ -744,23 +744,6 @@ static int handle_encryptable(const struct fstab_rec* rec)
}
}
static std::string extract_by_name_prefix(struct fstab* fstab) {
// We assume that there's an entry for the /misc mount point in the
// fstab file and use that to get the device file by-name prefix.
// The device needs not to have an actual /misc partition.
// e.g.,
// - /dev/block/platform/soc.0/7824900.sdhci/by-name/misc ->
// - /dev/block/platform/soc.0/7824900.sdhci/by-name/
struct fstab_rec* fstab_entry = fs_mgr_get_entry_for_mount_point(fstab, "/misc");
if (fstab_entry == nullptr) {
LERROR << "/misc mount point not found in fstab";
return "";
}
std::string full_path(fstab_entry->blk_device);
size_t end_slash = full_path.find_last_of("/");
return full_path.substr(0, end_slash + 1);
}
// TODO: add ueventd notifiers if they don't exist.
// This is just doing a wait_for_device for maximum of 1s
int fs_mgr_test_access(const char *device) {
@ -850,7 +833,7 @@ int fs_mgr_mount_all(struct fstab *fstab, int mount_mode)
if (fstab->recs[i].fs_mgr_flags & MF_AVB) {
if (!avb_handle) {
avb_handle = FsManagerAvbHandle::Open(extract_by_name_prefix(fstab));
avb_handle = FsManagerAvbHandle::Open(*fstab);
if (!avb_handle) {
LERROR << "Failed to open FsManagerAvbHandle";
return FS_MGR_MNTALL_FAIL;
@ -1060,7 +1043,7 @@ int fs_mgr_do_mount(struct fstab *fstab, const char *n_name, char *n_blk_device,
if (fstab->recs[i].fs_mgr_flags & MF_AVB) {
if (!avb_handle) {
avb_handle = FsManagerAvbHandle::Open(extract_by_name_prefix(fstab));
avb_handle = FsManagerAvbHandle::Open(*fstab);
if (!avb_handle) {
LERROR << "Failed to open FsManagerAvbHandle";
return FS_MGR_DOMNT_FAILED;

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@ -14,6 +14,8 @@
* limitations under the License.
*/
#include "fs_mgr_avb.h"
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
@ -38,9 +40,8 @@
#include <utils/Compat.h>
#include "fs_mgr.h"
#include "fs_mgr_avb.h"
#include "fs_mgr_avb_ops.h"
#include "fs_mgr_priv.h"
#include "fs_mgr_priv_avb_ops.h"
#include "fs_mgr_priv_dm_ioctl.h"
#include "fs_mgr_priv_sha.h"
@ -457,12 +458,21 @@ static bool get_hashtree_descriptor(const std::string& partition_name,
return true;
}
FsManagerAvbUniquePtr FsManagerAvbHandle::Open(const std::string& device_file_by_name_prefix) {
if (device_file_by_name_prefix.empty()) {
LERROR << "Missing device file by-name prefix";
FsManagerAvbUniquePtr FsManagerAvbHandle::Open(const fstab& fstab) {
FsManagerAvbOps avb_ops(fstab);
return DoOpen(&avb_ops);
}
FsManagerAvbUniquePtr FsManagerAvbHandle::Open(ByNameSymlinkMap&& by_name_symlink_map) {
if (by_name_symlink_map.empty()) {
LERROR << "Empty by_name_symlink_map when opening FsManagerAvbHandle";
return nullptr;
}
FsManagerAvbOps avb_ops(std::move(by_name_symlink_map));
return DoOpen(&avb_ops);
}
FsManagerAvbUniquePtr FsManagerAvbHandle::DoOpen(FsManagerAvbOps* avb_ops) {
// Gets the expected hash value of vbmeta images from kernel cmdline.
std::unique_ptr<FsManagerAvbVerifier> avb_verifier = FsManagerAvbVerifier::Create();
if (!avb_verifier) {
@ -476,8 +486,7 @@ FsManagerAvbUniquePtr FsManagerAvbHandle::Open(const std::string& device_file_by
return nullptr;
}
FsManagerAvbOps avb_ops(device_file_by_name_prefix);
AvbSlotVerifyResult verify_result = avb_ops.AvbSlotVerify(
AvbSlotVerifyResult verify_result = avb_ops->AvbSlotVerify(
fs_mgr_get_slot_suffix(), avb_verifier->IsDeviceUnlocked(), &avb_handle->avb_slot_data_);
// Only allow two verify results:

View File

@ -22,6 +22,8 @@
* SOFTWARE.
*/
#include "fs_mgr_priv_avb_ops.h"
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
@ -36,7 +38,6 @@
#include <utils/Compat.h>
#include "fs_mgr.h"
#include "fs_mgr_avb_ops.h"
#include "fs_mgr_priv.h"
static AvbIOResult read_from_partition(AvbOps* ops, const char* partition, int64_t offset,
@ -88,11 +89,7 @@ static AvbIOResult dummy_get_unique_guid_for_partition(AvbOps* ops ATTRIBUTE_UNU
return AVB_IO_RESULT_OK;
}
FsManagerAvbOps::FsManagerAvbOps(const std::string& device_file_by_name_prefix)
: device_file_by_name_prefix_(device_file_by_name_prefix) {
if (device_file_by_name_prefix_.back() != '/') {
device_file_by_name_prefix_ += '/';
}
void FsManagerAvbOps::InitializeAvbOps() {
// We only need to provide the implementation of read_from_partition()
// operation since that's all what is being used by the avb_slot_verify().
// Other I/O operations are only required in bootloader but not in
@ -109,13 +106,31 @@ FsManagerAvbOps::FsManagerAvbOps(const std::string& device_file_by_name_prefix)
avb_ops_.user_data = this;
}
FsManagerAvbOps::FsManagerAvbOps(std::map<std::string, std::string>&& by_name_symlink_map)
: by_name_symlink_map_(std::move(by_name_symlink_map)) {
InitializeAvbOps();
}
FsManagerAvbOps::FsManagerAvbOps(const fstab& fstab) {
// Constructs the by-name symlink map for each fstab record.
// /dev/block/platform/soc.0/7824900.sdhci/by-name/system_a =>
// by_name_symlink_map_["system_a"] = "/dev/block/platform/soc.0/7824900.sdhci/by-name/system_a"
for (int i = 0; i < fstab.num_entries; i++) {
std::string partition_name = basename(fstab.recs[i].blk_device);
by_name_symlink_map_[partition_name] = fstab.recs[i].blk_device;
}
InitializeAvbOps();
}
AvbIOResult FsManagerAvbOps::ReadFromPartition(const char* partition, int64_t offset,
size_t num_bytes, void* buffer,
size_t* out_num_read) {
// Appends |partition| to the device_file_by_name_prefix_, e.g.,
// - /dev/block/platform/soc.0/7824900.sdhci/by-name/ ->
// - /dev/block/platform/soc.0/7824900.sdhci/by-name/system_a
std::string path = device_file_by_name_prefix_ + partition;
const auto iter = by_name_symlink_map_.find(partition);
if (iter == by_name_symlink_map_.end()) {
LERROR << "by-name symlink not found for partition: '" << partition << "'";
return AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION;
}
std::string path = iter->second;
// Ensures the device path (a symlink created by init) is ready to
// access. fs_mgr_test_access() will test a few iterations if the
@ -126,7 +141,7 @@ AvbIOResult FsManagerAvbOps::ReadFromPartition(const char* partition, int64_t of
android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(path.c_str(), O_RDONLY | O_CLOEXEC)));
if (fd < 0) {
PERROR << "Failed to open " << path.c_str();
PERROR << "Failed to open " << path;
return AVB_IO_RESULT_ERROR_IO;
}
@ -150,8 +165,7 @@ AvbIOResult FsManagerAvbOps::ReadFromPartition(const char* partition, int64_t of
// for EOF).
ssize_t num_read = TEMP_FAILURE_RETRY(pread64(fd, buffer, num_bytes, offset));
if (num_read < 0 || (size_t)num_read != num_bytes) {
PERROR << "Failed to read " << num_bytes << " bytes from " << path.c_str() << " offset "
<< offset;
PERROR << "Failed to read " << num_bytes << " bytes from " << path << " offset " << offset;
return AVB_IO_RESULT_ERROR_IO;
}

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@ -22,8 +22,11 @@
* SOFTWARE.
*/
#ifndef __CORE_FS_MGR_AVB_OPS_H
#define __CORE_FS_MGR_AVB_OPS_H
#ifndef __CORE_FS_MGR_PRIV_AVB_OPS_H
#define __CORE_FS_MGR_PRIV_AVB_OPS_H
#include <map>
#include <string>
#include <libavb/libavb.h>
@ -43,7 +46,8 @@
//
class FsManagerAvbOps {
public:
FsManagerAvbOps(const std::string& device_file_by_name_prefix);
FsManagerAvbOps(const fstab& fstab);
FsManagerAvbOps(std::map<std::string, std::string>&& by_name_symlink_map);
static FsManagerAvbOps* GetInstanceFromAvbOps(AvbOps* ops) {
return reinterpret_cast<FsManagerAvbOps*>(ops->user_data);
@ -56,7 +60,9 @@ class FsManagerAvbOps {
AvbSlotVerifyData** out_data);
private:
void InitializeAvbOps();
AvbOps avb_ops_;
std::string device_file_by_name_prefix_;
std::map<std::string, std::string> by_name_symlink_map_;
};
#endif /* __CORE_FS_MGR_AVB_OPS_H */
#endif /* __CORE_FS_MGR_PRIV_AVB_OPS_H */

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@ -17,6 +17,7 @@
#ifndef __CORE_FS_MGR_AVB_H
#define __CORE_FS_MGR_AVB_H
#include <map>
#include <memory>
#include <string>
@ -31,9 +32,13 @@ enum FsManagerAvbHandleStatus {
kFsManagerAvbHandleErrorVerification = 2,
};
class FsManagerAvbOps;
class FsManagerAvbHandle;
using FsManagerAvbUniquePtr = std::unique_ptr<FsManagerAvbHandle>;
using ByNameSymlinkMap = std::map<std::string, std::string>;
// Provides a factory method to return a unique_ptr pointing to itself and the
// SetUpAvb() function to extract dm-verity parameters from AVB metadata to
// load verity table into kernel through ioctl.
@ -49,6 +54,13 @@ class FsManagerAvbHandle {
// A typical usage will be:
// - FsManagerAvbUniquePtr handle = FsManagerAvbHandle::Open();
//
// There are two overloaded Open() functions with a single parameter.
// The argument can be a ByNameSymlinkMap describing the mapping from partition
// name to by-name symlink, or a fstab file to which the ByNameSymlinkMap is
// constructed from. e.g.,
// - /dev/block/platform/soc.0/7824900.sdhci/by-name/system_a ->
// - ByNameSymlinkMap["system_a"] = "/dev/block/platform/soc.0/7824900.sdhci/by-name/system_a"
//
// Possible return values:
// - nullptr: any error when reading and verifying the metadata,
// e.g., I/O error, digest value mismatch, size mismatch, etc.
@ -61,7 +73,8 @@ class FsManagerAvbHandle {
// - a valid unique_ptr with status kFsMgrAvbHandleSuccess: the metadata
// is verified and can be trusted.
//
static FsManagerAvbUniquePtr Open(const std::string& device_file_by_name_prefix);
static FsManagerAvbUniquePtr Open(const fstab& fstab);
static FsManagerAvbUniquePtr Open(ByNameSymlinkMap&& by_name_symlink_map);
// Sets up dm-verity on the given fstab entry.
// The 'wait_for_verity_dev' parameter makes this function wait for the
@ -88,10 +101,10 @@ class FsManagerAvbHandle {
}
};
protected:
FsManagerAvbHandle() : avb_slot_data_(nullptr), status_(kFsManagerAvbHandleUninitialized) {}
private:
FsManagerAvbHandle() : avb_slot_data_(nullptr), status_(kFsManagerAvbHandleUninitialized) {}
static FsManagerAvbUniquePtr DoOpen(FsManagerAvbOps* avb_ops);
AvbSlotVerifyData* avb_slot_data_;
FsManagerAvbHandleStatus status_;
std::string avb_version_;

View File

@ -47,18 +47,22 @@ class FirstStageMount {
bool InitDevices();
protected:
void InitRequiredDevices(std::set<std::string>* devices_partition_names);
void InitRequiredDevices();
void InitVerityDevice(const std::string& verity_device);
bool MountPartitions();
virtual bool GetRequiredDevices(std::set<std::string>* out_devices_partition_names,
bool* out_need_dm_verity) = 0;
virtual coldboot_action_t ColdbootCallback(uevent* uevent);
// Pure virtual functions.
virtual bool GetRequiredDevices() = 0;
virtual bool SetUpDmVerity(fstab_rec* fstab_rec) = 0;
bool need_dm_verity_;
// Device tree fstab entries.
std::unique_ptr<fstab, decltype(&fs_mgr_free_fstab)> device_tree_fstab_;
// Eligible first stage mount candidates, only allow /system, /vendor and/or /odm.
std::vector<fstab_rec*> mount_fstab_recs_;
std::set<std::string> required_devices_partition_names_;
};
class FirstStageMountVBootV1 : public FirstStageMount {
@ -67,27 +71,26 @@ class FirstStageMountVBootV1 : public FirstStageMount {
~FirstStageMountVBootV1() override = default;
protected:
bool GetRequiredDevices(std::set<std::string>* out_devices_partition_names,
bool* out_need_dm_verity) override;
bool GetRequiredDevices() override;
bool SetUpDmVerity(fstab_rec* fstab_rec) override;
};
class FirstStageMountVBootV2 : public FirstStageMount {
public:
friend void SetInitAvbVersionInRecovery();
FirstStageMountVBootV2();
~FirstStageMountVBootV2() override = default;
const std::string& by_name_prefix() const { return device_tree_by_name_prefix_; }
protected:
bool GetRequiredDevices(std::set<std::string>* out_devices_partition_names,
bool* out_need_dm_verity) override;
coldboot_action_t ColdbootCallback(uevent* uevent) override;
bool GetRequiredDevices() override;
bool SetUpDmVerity(fstab_rec* fstab_rec) override;
bool InitAvbHandle();
std::string device_tree_vbmeta_parts_;
std::string device_tree_by_name_prefix_;
FsManagerAvbUniquePtr avb_handle_;
ByNameSymlinkMap by_name_symlink_map_;
};
// Static Functions
@ -102,7 +105,8 @@ static bool inline IsRecoveryMode() {
// Class Definitions
// -----------------
FirstStageMount::FirstStageMount() : device_tree_fstab_(fs_mgr_read_fstab_dt(), fs_mgr_free_fstab) {
FirstStageMount::FirstStageMount()
: need_dm_verity_(false), device_tree_fstab_(fs_mgr_read_fstab_dt(), fs_mgr_free_fstab) {
if (!device_tree_fstab_) {
LOG(ERROR) << "Failed to read fstab from device tree";
return;
@ -136,13 +140,30 @@ bool FirstStageMount::DoFirstStageMount() {
}
bool FirstStageMount::InitDevices() {
bool need_dm_verity;
std::set<std::string> devices_partition_names;
if (!GetRequiredDevices()) return false;
// The partition name in devices_partition_names MUST have A/B suffix when A/B is used.
if (!GetRequiredDevices(&devices_partition_names, &need_dm_verity)) return false;
InitRequiredDevices();
if (need_dm_verity) {
// InitRequiredDevices() will remove found partitions from required_devices_partition_names_.
// So if it isn't empty here, it means some partitions are not found.
if (!required_devices_partition_names_.empty()) {
LOG(ERROR) << __FUNCTION__ << "(): partition(s) not found: "
<< android::base::Join(required_devices_partition_names_, ", ");
return false;
} else {
return true;
}
}
// Creates devices with uevent->partition_name matching one in the member variable
// required_devices_partition_names_. Found partitions will then be removed from it
// for the subsequent member function to check which devices are NOT created.
void FirstStageMount::InitRequiredDevices() {
if (required_devices_partition_names_.empty()) {
return;
}
if (need_dm_verity_) {
const std::string dm_path = "/devices/virtual/misc/device-mapper";
device_init(("/sys" + dm_path).c_str(), [&dm_path](uevent* uevent) -> coldboot_action_t {
if (uevent->path == dm_path) return COLDBOOT_STOP;
@ -150,58 +171,40 @@ bool FirstStageMount::InitDevices() {
});
}
bool success = false;
InitRequiredDevices(&devices_partition_names);
// InitRequiredDevices() will remove found partitions from devices_partition_names.
// So if it isn't empty here, it means some partitions are not found.
if (!devices_partition_names.empty()) {
LOG(ERROR) << __FUNCTION__ << "(): partition(s) not found: "
<< android::base::Join(devices_partition_names, ", ");
} else {
success = true;
}
device_init(nullptr,
[this](uevent* uevent) -> coldboot_action_t { return ColdbootCallback(uevent); });
device_close();
return success;
}
// Creates devices with uevent->partition_name matching one in the in/out
// devices_partition_names. Found partitions will then be removed from the
// devices_partition_names for the caller to check which devices are NOT created.
void FirstStageMount::InitRequiredDevices(std::set<std::string>* devices_partition_names) {
if (devices_partition_names->empty()) {
return;
coldboot_action_t FirstStageMount::ColdbootCallback(uevent* uevent) {
// We need platform devices to create symlinks.
if (uevent->subsystem == "platform") {
return COLDBOOT_CREATE;
}
device_init(nullptr, [=](uevent* uevent) -> coldboot_action_t {
// We need platform devices to create symlinks.
if (uevent->subsystem == "platform") {
return COLDBOOT_CREATE;
}
// Ignores everything that is not a block device.
if (uevent->subsystem != "block") {
return COLDBOOT_CONTINUE;
}
// Ignores everything that is not a block device.
if (uevent->subsystem != "block") {
return COLDBOOT_CONTINUE;
}
if (!uevent->partition_name.empty()) {
// Matches partition name to create device nodes.
// Both devices_partition_names and uevent->partition_name have A/B
// suffix when A/B is used.
auto iter = devices_partition_names->find(uevent->partition_name);
if (iter != devices_partition_names->end()) {
LOG(VERBOSE) << __FUNCTION__ << "(): found partition: " << *iter;
devices_partition_names->erase(iter);
if (devices_partition_names->empty()) {
return COLDBOOT_STOP; // Found all partitions, stop coldboot.
} else {
return COLDBOOT_CREATE; // Creates this device and continue to find others.
}
if (!uevent->partition_name.empty()) {
// Matches partition name to create device nodes.
// Both required_devices_partition_names_ and uevent->partition_name have A/B
// suffix when A/B is used.
auto iter = required_devices_partition_names_.find(uevent->partition_name);
if (iter != required_devices_partition_names_.end()) {
LOG(VERBOSE) << __FUNCTION__ << "(): found partition: " << *iter;
required_devices_partition_names_.erase(iter);
if (required_devices_partition_names_.empty()) {
return COLDBOOT_STOP; // Found all partitions, stop coldboot.
} else {
return COLDBOOT_CREATE; // Creates this device and continue to find others.
}
}
// Not found a partition or find an unneeded partition, continue to find others.
return COLDBOOT_CONTINUE;
});
}
// Not found a partition or find an unneeded partition, continue to find others.
return COLDBOOT_CONTINUE;
}
// Creates "/dev/block/dm-XX" for dm-verity by running coldboot on /sys/block/dm-XX.
@ -233,10 +236,9 @@ bool FirstStageMount::MountPartitions() {
return true;
}
bool FirstStageMountVBootV1::GetRequiredDevices(std::set<std::string>* out_devices_partition_names,
bool* out_need_dm_verity) {
bool FirstStageMountVBootV1::GetRequiredDevices() {
std::string verity_loc_device;
*out_need_dm_verity = false;
need_dm_verity_ = false;
for (auto fstab_rec : mount_fstab_recs_) {
// Don't allow verifyatboot in the first stage.
@ -246,7 +248,7 @@ bool FirstStageMountVBootV1::GetRequiredDevices(std::set<std::string>* out_devic
}
// Checks for verified partitions.
if (fs_mgr_is_verified(fstab_rec)) {
*out_need_dm_verity = true;
need_dm_verity_ = true;
}
// Checks if verity metadata is on a separate partition. Note that it is
// not partition specific, so there must be only one additional partition
@ -265,11 +267,11 @@ bool FirstStageMountVBootV1::GetRequiredDevices(std::set<std::string>* out_devic
// Includes the partition names of fstab records and verity_loc_device (if any).
// Notes that fstab_rec->blk_device has A/B suffix updated by fs_mgr when A/B is used.
for (auto fstab_rec : mount_fstab_recs_) {
out_devices_partition_names->emplace(basename(fstab_rec->blk_device));
required_devices_partition_names_.emplace(basename(fstab_rec->blk_device));
}
if (!verity_loc_device.empty()) {
out_devices_partition_names->emplace(basename(verity_loc_device.c_str()));
required_devices_partition_names_.emplace(basename(verity_loc_device.c_str()));
}
return true;
@ -292,15 +294,13 @@ bool FirstStageMountVBootV1::SetUpDmVerity(fstab_rec* fstab_rec) {
}
// FirstStageMountVBootV2 constructor.
// Gets the vbmeta configurations from device tree.
// Specifically, the 'parts' and 'by_name_prefix' below.
// Gets the vbmeta partitions from device tree.
// /{
// firmware {
// android {
// vbmeta {
// compatible = "android,vbmeta";
// parts = "vbmeta,boot,system,vendor"
// by_name_prefix = "/dev/block/platform/soc.0/f9824900.sdhci/by-name/"
// };
// };
// };
@ -310,31 +310,24 @@ FirstStageMountVBootV2::FirstStageMountVBootV2() : avb_handle_(nullptr) {
PLOG(ERROR) << "Failed to read vbmeta/parts from device tree";
return;
}
// TODO: removes by_name_prefix to allow partitions on different block devices.
if (!read_android_dt_file("vbmeta/by_name_prefix", &device_tree_by_name_prefix_)) {
PLOG(ERROR) << "Failed to read vbmeta/by_name_prefix from dt";
return;
}
}
bool FirstStageMountVBootV2::GetRequiredDevices(std::set<std::string>* out_devices_partition_names,
bool* out_need_dm_verity) {
*out_need_dm_verity = false;
bool FirstStageMountVBootV2::GetRequiredDevices() {
need_dm_verity_ = false;
// fstab_rec->blk_device has A/B suffix.
for (auto fstab_rec : mount_fstab_recs_) {
if (fs_mgr_is_avb(fstab_rec)) {
*out_need_dm_verity = true;
need_dm_verity_ = true;
}
out_devices_partition_names->emplace(basename(fstab_rec->blk_device));
required_devices_partition_names_.emplace(basename(fstab_rec->blk_device));
}
// libavb verifies AVB metadata on all verified partitions at once.
// e.g., The device_tree_vbmeta_parts_ will be "vbmeta,boot,system,vendor"
// for libavb to verify metadata, even if there is only /vendor in the
// above mount_fstab_recs_.
if (*out_need_dm_verity) {
if (need_dm_verity_) {
if (device_tree_vbmeta_parts_.empty()) {
LOG(ERROR) << "Missing vbmeta parts in device tree";
return false;
@ -342,16 +335,45 @@ bool FirstStageMountVBootV2::GetRequiredDevices(std::set<std::string>* out_devic
std::vector<std::string> partitions = android::base::Split(device_tree_vbmeta_parts_, ",");
std::string ab_suffix = fs_mgr_get_slot_suffix();
for (const auto& partition : partitions) {
// out_devices_partition_names is of type std::set so it's not an issue to emplace
// a partition twice. e.g., /vendor might be in both places:
// required_devices_partition_names_ is of type std::set so it's not an issue
// to emplace a partition twice. e.g., /vendor might be in both places:
// - device_tree_vbmeta_parts_ = "vbmeta,boot,system,vendor"
// - mount_fstab_recs_: /vendor_a
out_devices_partition_names->emplace(partition + ab_suffix);
required_devices_partition_names_.emplace(partition + ab_suffix);
}
}
return true;
}
coldboot_action_t FirstStageMountVBootV2::ColdbootCallback(uevent* uevent) {
// Invokes the parent function to see if any desired partition has been found.
// If yes, record the by-name symlink for creating FsManagerAvbHandle later.
coldboot_action_t parent_callback_ret = FirstStageMount::ColdbootCallback(uevent);
// Skips the uevent if the parent function returns COLDBOOT_CONTINUE (meaning
// that the uevent was skipped) or there is no uevent->partition_name to
// create the by-name symlink.
if (parent_callback_ret != COLDBOOT_CONTINUE && !uevent->partition_name.empty()) {
// get_block_device_symlinks() will return three symlinks at most, depending on
// the content of uevent. by-name symlink will be at [0] if uevent->partition_name
// is not empty. e.g.,
// - /dev/block/platform/soc.0/f9824900.sdhci/by-name/modem
// - /dev/block/platform/soc.0/f9824900.sdhci/by-num/p1
// - /dev/block/platform/soc.0/f9824900.sdhci/mmcblk0p1
std::vector<std::string> links = get_block_device_symlinks(uevent);
if (!links.empty()) {
auto[it, inserted] = by_name_symlink_map_.emplace(uevent->partition_name, links[0]);
if (!inserted) {
LOG(ERROR) << "Partition '" << uevent->partition_name
<< "' already existed in the by-name symlink map with a value of '"
<< it->second << "', new value '" << links[0] << "' will be ignored.";
}
}
}
return parent_callback_ret;
}
bool FirstStageMountVBootV2::SetUpDmVerity(fstab_rec* fstab_rec) {
if (fs_mgr_is_avb(fstab_rec)) {
if (!InitAvbHandle()) return false;
@ -371,7 +393,14 @@ bool FirstStageMountVBootV2::SetUpDmVerity(fstab_rec* fstab_rec) {
bool FirstStageMountVBootV2::InitAvbHandle() {
if (avb_handle_) return true; // Returns true if the handle is already initialized.
avb_handle_ = FsManagerAvbHandle::Open(device_tree_by_name_prefix_);
if (by_name_symlink_map_.empty()) {
LOG(ERROR) << "by_name_symlink_map_ is empty";
return false;
}
avb_handle_ = FsManagerAvbHandle::Open(std::move(by_name_symlink_map_));
by_name_symlink_map_.clear(); // Removes all elements after the above std::move().
if (!avb_handle_) {
PLOG(ERROR) << "Failed to open FsManagerAvbHandle";
return false;
@ -427,7 +456,8 @@ void SetInitAvbVersionInRecovery() {
return;
}
FsManagerAvbUniquePtr avb_handle = FsManagerAvbHandle::Open(avb_first_mount.by_name_prefix());
FsManagerAvbUniquePtr avb_handle =
FsManagerAvbHandle::Open(std::move(avb_first_mount.by_name_symlink_map_));
if (!avb_handle) {
PLOG(ERROR) << "Failed to open FsManagerAvbHandle for INIT_AVB_VERSION";
return;