#include "KeyStorage.h"
#include "Utils.h"
+#include <algorithm>
#include <iomanip>
#include <map>
#include <set>
-#include <string>
#include <sstream>
+#include <string>
-#include <stdio.h>
-#include <errno.h>
#include <dirent.h>
-#include <sys/mount.h>
-#include <sys/types.h>
-#include <sys/stat.h>
+#include <errno.h>
#include <fcntl.h>
-#include <cutils/properties.h>
+#include <limits.h>
#include <openssl/sha.h>
#include <selinux/android.h>
+#include <stdio.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
#include <private/android_filesystem_config.h>
-#include "key_control.h"
#include "cryptfs.h"
#include "ext4_crypt.h"
-
-#define LOG_TAG "Ext4Crypt"
+#include "key_control.h"
#define EMULATED_USES_SELINUX 0
+#define MANAGE_MISC_DIRS 0
#include <cutils/fs.h>
-#include <cutils/log.h>
-#include <cutils/klog.h>
#include <android-base/file.h>
#include <android-base/logging.h>
static constexpr int FLAG_STORAGE_DE = 1 << 0;
static constexpr int FLAG_STORAGE_CE = 1 << 1;
-static bool e4crypt_is_native() {
- char value[PROPERTY_VALUE_MAX];
- property_get("ro.crypto.type", value, "none");
- return !strcmp(value, "file");
-}
-
-static bool e4crypt_is_emulated() {
- return property_get_bool("persist.sys.emulate_fbe", false);
-}
-
-static const char* escape_null(const char* value) {
- return (value == nullptr) ? "null" : value;
-}
-
namespace {
- // Key length in bits
- const int key_length = 128;
- static_assert(key_length % 8 == 0,
- "Key length must be multiple of 8 bits");
+const std::string device_key_dir = std::string() + DATA_MNT_POINT + e4crypt_unencrypted_folder;
+const std::string device_key_path = device_key_dir + "/key";
+const std::string device_key_temp = device_key_dir + "/temp";
- const std::string device_key_leaf = "/unencrypted/key";
- const std::string device_key_temp = "/unencrypted/temp";
+const std::string user_key_dir = std::string() + DATA_MNT_POINT + "/misc/vold/user_keys";
+const std::string user_key_temp = user_key_dir + "/temp";
- const std::string user_key_dir = std::string() + DATA_MNT_POINT + "/misc/vold/user_keys";
- const std::string user_key_temp = user_key_dir + "/temp";
+bool s_global_de_initialized = false;
- bool s_enabled = false;
+// Some users are ephemeral, don't try to wipe their keys from disk
+std::set<userid_t> s_ephemeral_users;
- // Some users are ephemeral, don't try to wipe their keys from disk
- std::set<userid_t> s_ephemeral_users;
+// Map user ids to key references
+std::map<userid_t, std::string> s_de_key_raw_refs;
+std::map<userid_t, std::string> s_ce_key_raw_refs;
+// TODO abolish this map. Keys should not be long-lived in user memory, only kernel memory.
+// See b/26948053
+std::map<userid_t, std::string> s_ce_keys;
- // Map user ids to key references
- std::map<userid_t, std::string> s_de_key_raw_refs;
- std::map<userid_t, std::string> s_ce_key_raw_refs;
- // TODO abolish this map. Keys should not be long-lived in user memory, only kernel memory.
- // See b/26948053
- std::map<userid_t, std::string> s_ce_keys;
+// ext4enc:TODO get this const from somewhere good
+const int EXT4_KEY_DESCRIPTOR_SIZE = 8;
- // ext4enc:TODO get this const from somewhere good
- const int EXT4_KEY_DESCRIPTOR_SIZE = 8;
+// ext4enc:TODO Include structure from somewhere sensible
+// MUST be in sync with ext4_crypto.c in kernel
+constexpr int EXT4_ENCRYPTION_MODE_AES_256_XTS = 1;
+constexpr int EXT4_AES_256_XTS_KEY_SIZE = 64;
+constexpr int EXT4_MAX_KEY_SIZE = 64;
+struct ext4_encryption_key {
+ uint32_t mode;
+ char raw[EXT4_MAX_KEY_SIZE];
+ uint32_t size;
+};
+}
- // ext4enc:TODO Include structure from somewhere sensible
- // MUST be in sync with ext4_crypto.c in kernel
- const int EXT4_MAX_KEY_SIZE = 64;
- const int EXT4_ENCRYPTION_MODE_AES_256_XTS = 1;
- struct ext4_encryption_key {
- uint32_t mode;
- char raw[EXT4_MAX_KEY_SIZE];
- uint32_t size;
- };
+static bool e4crypt_is_emulated() {
+ return property_get_bool("persist.sys.emulate_fbe", false);
}
-// TODO replace with proper function to test for file encryption
-int e4crypt_crypto_complete(const char* path)
-{
- return e4crypt_is_native() ? 0 : -1;
+static const char* escape_null(const char* value) {
+ return (value == nullptr) ? "null" : value;
}
// Get raw keyref - used to make keyname and to pass to ioctl
-static std::string generate_key_ref(const char* key, int length)
-{
+static std::string generate_key_ref(const char* key, int length) {
SHA512_CTX c;
SHA512_Init(&c);
unsigned char key_ref2[SHA512_DIGEST_LENGTH];
SHA512_Final(key_ref2, &c);
+ static_assert(EXT4_KEY_DESCRIPTOR_SIZE <= SHA512_DIGEST_LENGTH,
+ "Hash too short for descriptor");
return std::string((char*)key_ref2, EXT4_KEY_DESCRIPTOR_SIZE);
}
-static ext4_encryption_key fill_key(const std::string &key)
-{
- // ext4enc:TODO Currently raw key is required to be of length
- // sizeof(ext4_key.raw) == EXT4_MAX_KEY_SIZE, so zero pad to
- // this length. Change when kernel bug is fixed.
- ext4_encryption_key ext4_key = {EXT4_ENCRYPTION_MODE_AES_256_XTS,
- {0},
- sizeof(ext4_key.raw)};
- memset(ext4_key.raw, 0, sizeof(ext4_key.raw));
- static_assert(key_length / 8 <= sizeof(ext4_key.raw),
- "Key too long!");
- memcpy(ext4_key.raw, &key[0], key.size());
- return ext4_key;
+static bool fill_key(const std::string& key, ext4_encryption_key* ext4_key) {
+ if (key.size() != EXT4_AES_256_XTS_KEY_SIZE) {
+ LOG(ERROR) << "Wrong size key " << key.size();
+ return false;
+ }
+ static_assert(EXT4_AES_256_XTS_KEY_SIZE <= sizeof(ext4_key->raw), "Key too long!");
+ ext4_key->mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
+ ext4_key->size = key.size();
+ memset(ext4_key->raw, 0, sizeof(ext4_key->raw));
+ memcpy(ext4_key->raw, key.data(), key.size());
+ return true;
}
-static std::string keyname(const std::string &raw_ref)
-{
+static std::string keyname(const std::string& raw_ref) {
std::ostringstream o;
o << "ext4:";
- for (auto i = raw_ref.begin(); i != raw_ref.end(); ++i) {
- o << std::hex << std::setw(2) << std::setfill('0') << (int)*i;
+ for (auto i : raw_ref) {
+ o << std::hex << std::setw(2) << std::setfill('0') << (int)i;
}
return o.str();
}
// Get the keyring we store all keys in
-static key_serial_t e4crypt_keyring()
-{
- return keyctl_search(KEY_SPEC_SESSION_KEYRING, "keyring", "e4crypt", 0);
+static bool e4crypt_keyring(key_serial_t* device_keyring) {
+ *device_keyring = keyctl_search(KEY_SPEC_SESSION_KEYRING, "keyring", "e4crypt", 0);
+ if (*device_keyring == -1) {
+ PLOG(ERROR) << "Unable to find device keyring";
+ return false;
+ }
+ return true;
}
// Install password into global keyring
// Return raw key reference for use in policy
-static bool install_key(const std::string &key, std::string &raw_ref)
-{
- if (key.size() != key_length/8) {
- LOG(ERROR) << "Wrong size key " << key.size();
- return false;
- }
- auto ext4_key = fill_key(key);
- raw_ref = generate_key_ref(ext4_key.raw, ext4_key.size);
- auto ref = keyname(raw_ref);
- key_serial_t device_keyring = e4crypt_keyring();
- key_serial_t key_id = add_key("logon", ref.c_str(),
- (void*)&ext4_key, sizeof(ext4_key),
- device_keyring);
+static bool install_key(const std::string& key, std::string* raw_ref) {
+ ext4_encryption_key ext4_key;
+ if (!fill_key(key, &ext4_key)) return false;
+ *raw_ref = generate_key_ref(ext4_key.raw, ext4_key.size);
+ auto ref = keyname(*raw_ref);
+ key_serial_t device_keyring;
+ if (!e4crypt_keyring(&device_keyring)) return false;
+ key_serial_t key_id =
+ add_key("logon", ref.c_str(), (void*)&ext4_key, sizeof(ext4_key), device_keyring);
if (key_id == -1) {
PLOG(ERROR) << "Failed to insert key into keyring " << device_keyring;
return false;
}
- LOG(INFO) << "Added key " << key_id << " (" << ref << ") to keyring "
- << device_keyring << " in process " << getpid();
+ LOG(DEBUG) << "Added key " << key_id << " (" << ref << ") to keyring " << device_keyring
+ << " in process " << getpid();
return true;
}
return StringPrintf("%s/de/%d", user_key_dir.c_str(), user_id);
}
-static std::string get_ce_key_path(userid_t user_id) {
- return StringPrintf("%s/ce/%d/current", user_key_dir.c_str(), user_id);
+static std::string get_ce_key_directory_path(userid_t user_id) {
+ return StringPrintf("%s/ce/%d", user_key_dir.c_str(), user_id);
}
-static bool read_and_install_user_ce_key(
- userid_t user_id, const android::vold::KeyAuthentication &auth) {
+// Returns the keys newest first
+static std::vector<std::string> get_ce_key_paths(const std::string& directory_path) {
+ auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(directory_path.c_str()), closedir);
+ if (!dirp) {
+ PLOG(ERROR) << "Unable to open ce key directory: " + directory_path;
+ return std::vector<std::string>();
+ }
+ std::vector<std::string> result;
+ for (;;) {
+ errno = 0;
+ auto const entry = readdir(dirp.get());
+ if (!entry) {
+ if (errno) {
+ PLOG(ERROR) << "Unable to read ce key directory: " + directory_path;
+ return std::vector<std::string>();
+ }
+ break;
+ }
+ if (entry->d_type != DT_DIR || entry->d_name[0] != 'c') {
+ LOG(DEBUG) << "Skipping non-key " << entry->d_name;
+ continue;
+ }
+ result.emplace_back(directory_path + "/" + entry->d_name);
+ }
+ std::sort(result.begin(), result.end());
+ std::reverse(result.begin(), result.end());
+ return result;
+}
+
+static std::string get_ce_key_current_path(const std::string& directory_path) {
+ return directory_path + "/current";
+}
+
+static bool get_ce_key_new_path(const std::string& directory_path,
+ const std::vector<std::string>& paths,
+ std::string *ce_key_path) {
+ if (paths.empty()) {
+ *ce_key_path = get_ce_key_current_path(directory_path);
+ return true;
+ }
+ for (unsigned int i = 0; i < UINT_MAX; i++) {
+ auto const candidate = StringPrintf("%s/cx%010u", directory_path.c_str(), i);
+ if (paths[0] < candidate) {
+ *ce_key_path = candidate;
+ return true;
+ }
+ }
+ return false;
+}
+
+// Discard all keys but the named one; rename it to canonical name.
+// No point in acting on errors in this; ignore them.
+static void fixate_user_ce_key(const std::string& directory_path, const std::string &to_fix,
+ const std::vector<std::string>& paths) {
+ for (auto const other_path: paths) {
+ if (other_path != to_fix) {
+ android::vold::destroyKey(other_path);
+ }
+ }
+ auto const current_path = get_ce_key_current_path(directory_path);
+ if (to_fix != current_path) {
+ LOG(DEBUG) << "Renaming " << to_fix << " to " << current_path;
+ if (rename(to_fix.c_str(), current_path.c_str()) != 0) {
+ PLOG(WARNING) << "Unable to rename " << to_fix << " to " << current_path;
+ }
+ }
+}
+
+static bool read_and_fixate_user_ce_key(userid_t user_id,
+ const android::vold::KeyAuthentication& auth,
+ std::string *ce_key) {
+ auto const directory_path = get_ce_key_directory_path(user_id);
+ auto const paths = get_ce_key_paths(directory_path);
+ for (auto const ce_key_path: paths) {
+ LOG(DEBUG) << "Trying user CE key " << ce_key_path;
+ if (android::vold::retrieveKey(ce_key_path, auth, ce_key)) {
+ LOG(DEBUG) << "Successfully retrieved key";
+ fixate_user_ce_key(directory_path, ce_key_path, paths);
+ return true;
+ }
+ }
+ LOG(ERROR) << "Failed to find working ce key for user " << user_id;
+ return false;
+}
+
+static bool read_and_install_user_ce_key(userid_t user_id,
+ const android::vold::KeyAuthentication& auth) {
if (s_ce_key_raw_refs.count(user_id) != 0) return true;
- const auto ce_key_path = get_ce_key_path(user_id);
std::string ce_key;
- if (!android::vold::retrieveKey(ce_key_path, auth, ce_key)) return false;
+ if (!read_and_fixate_user_ce_key(user_id, auth, &ce_key)) return false;
std::string ce_raw_ref;
- if (!install_key(ce_key, ce_raw_ref)) return false;
+ if (!install_key(ce_key, &ce_raw_ref)) return false;
s_ce_keys[user_id] = ce_key;
s_ce_key_raw_refs[user_id] = ce_raw_ref;
LOG(DEBUG) << "Installed ce key for user " << user_id;
return true;
}
-static bool prepare_dir(const std::string &dir, mode_t mode, uid_t uid, gid_t gid) {
+static bool prepare_dir(const std::string& dir, mode_t mode, uid_t uid, gid_t gid) {
LOG(DEBUG) << "Preparing: " << dir;
if (fs_prepare_dir(dir.c_str(), mode, uid, gid) != 0) {
PLOG(ERROR) << "Failed to prepare " << dir;
return true;
}
-static bool random_key(std::string &key) {
- if (android::vold::ReadRandomBytes(key_length / 8, key) != 0) {
+static bool destroy_dir(const std::string& dir) {
+ LOG(DEBUG) << "Destroying: " << dir;
+ if (rmdir(dir.c_str()) != 0 && errno != ENOENT) {
+ PLOG(ERROR) << "Failed to destroy " << dir;
+ return false;
+ }
+ return true;
+}
+
+static bool random_key(std::string* key) {
+ if (android::vold::ReadRandomBytes(EXT4_AES_256_XTS_KEY_SIZE, *key) != 0) {
// TODO status_t plays badly with PLOG, fix it.
LOG(ERROR) << "Random read failed";
return false;
return true;
}
-static bool path_exists(const std::string &path) {
+static bool path_exists(const std::string& path) {
return access(path.c_str(), F_OK) == 0;
}
// NB this assumes that there is only one thread listening for crypt commands, because
// it creates keys in a fixed location.
-static bool store_key(const std::string &key_path,
- const android::vold::KeyAuthentication &auth, const std::string &key) {
+static bool store_key(const std::string& key_path, const std::string& tmp_path,
+ const android::vold::KeyAuthentication& auth, const std::string& key) {
if (path_exists(key_path)) {
LOG(ERROR) << "Already exists, cannot create key at: " << key_path;
return false;
}
- if (path_exists(user_key_temp)) {
- android::vold::destroyKey(user_key_temp);
+ if (path_exists(tmp_path)) {
+ android::vold::destroyKey(tmp_path); // May be partially created so ignore errors
}
- if (!android::vold::storeKey(user_key_temp, auth, key)) return false;
- if (rename(user_key_temp.c_str(), key_path.c_str()) != 0) {
+ if (!android::vold::storeKey(tmp_path, auth, key)) return false;
+ if (rename(tmp_path.c_str(), key_path.c_str()) != 0) {
PLOG(ERROR) << "Unable to move new key to location: " << key_path;
return false;
}
static bool create_and_install_user_keys(userid_t user_id, bool create_ephemeral) {
std::string de_key, ce_key;
- if (!random_key(de_key)) return false;
- if (!random_key(ce_key)) return false;
+ if (!random_key(&de_key)) return false;
+ if (!random_key(&ce_key)) return false;
if (create_ephemeral) {
// If the key should be created as ephemeral, don't store it.
s_ephemeral_users.insert(user_id);
} else {
- if (!store_key(get_de_key_path(user_id), kEmptyAuthentication, de_key)) return false;
- if (!prepare_dir(user_key_dir + "/ce/" + std::to_string(user_id),
- 0700, AID_ROOT, AID_ROOT)) return false;
- if (!store_key(get_ce_key_path(user_id), kEmptyAuthentication, ce_key)) return false;
+ auto const directory_path = get_ce_key_directory_path(user_id);
+ if (!prepare_dir(directory_path, 0700, AID_ROOT, AID_ROOT)) return false;
+ auto const paths = get_ce_key_paths(directory_path);
+ std::string ce_key_path;
+ if (!get_ce_key_new_path(directory_path, paths, &ce_key_path)) return false;
+ if (!store_key(ce_key_path, user_key_temp,
+ kEmptyAuthentication, ce_key)) return false;
+ fixate_user_ce_key(directory_path, ce_key_path, paths);
+ // Write DE key second; once this is written, all is good.
+ if (!store_key(get_de_key_path(user_id), user_key_temp,
+ kEmptyAuthentication, de_key)) return false;
}
std::string de_raw_ref;
- if (!install_key(de_key, de_raw_ref)) return false;
+ if (!install_key(de_key, &de_raw_ref)) return false;
s_de_key_raw_refs[user_id] = de_raw_ref;
std::string ce_raw_ref;
- if (!install_key(ce_key, ce_raw_ref)) return false;
+ if (!install_key(ce_key, &ce_raw_ref)) return false;
s_ce_keys[user_id] = ce_key;
s_ce_key_raw_refs[user_id] = ce_raw_ref;
LOG(DEBUG) << "Created keys for user " << user_id;
return true;
}
-static bool lookup_key_ref(const std::map<userid_t, std::string> &key_map,
- userid_t user_id, std::string &raw_ref) {
+static bool lookup_key_ref(const std::map<userid_t, std::string>& key_map, userid_t user_id,
+ std::string* raw_ref) {
auto refi = key_map.find(user_id);
if (refi == key_map.end()) {
LOG(ERROR) << "Cannot find key for " << user_id;
return false;
}
- raw_ref = refi->second;
+ *raw_ref = refi->second;
return true;
}
-static bool ensure_policy(const std::string &raw_ref, const std::string& path) {
+static bool ensure_policy(const std::string& raw_ref, const std::string& path) {
if (e4crypt_policy_ensure(path.c_str(), raw_ref.data(), raw_ref.size()) != 0) {
LOG(ERROR) << "Failed to set policy on: " << path;
return false;
return true;
}
-static bool is_numeric(const char *name) {
- for (const char *p = name; *p != '\0'; p++) {
- if (!isdigit(*p))
- return false;
+static bool is_numeric(const char* name) {
+ for (const char* p = name; *p != '\0'; p++) {
+ if (!isdigit(*p)) return false;
}
return true;
}
static bool load_all_de_keys() {
auto de_dir = user_key_dir + "/de";
- auto dirp = std::unique_ptr<DIR, int(*)(DIR*)>(opendir(de_dir.c_str()), closedir);
+ auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(de_dir.c_str()), closedir);
if (!dirp) {
PLOG(ERROR) << "Unable to read de key directory";
return false;
if (s_de_key_raw_refs.count(user_id) == 0) {
auto key_path = de_dir + "/" + entry->d_name;
std::string key;
- if (!android::vold::retrieveKey(key_path, kEmptyAuthentication, key)) return false;
+ if (!android::vold::retrieveKey(key_path, kEmptyAuthentication, &key)) return false;
std::string raw_ref;
- if (!install_key(key, raw_ref)) return false;
+ if (!install_key(key, &raw_ref)) return false;
s_de_key_raw_refs[user_id] = raw_ref;
LOG(DEBUG) << "Installed de key for user " << user_id;
}
return true;
}
-int e4crypt_enable(const char* path)
-{
- LOG(INFO) << "e4crypt_enable";
+bool e4crypt_initialize_global_de() {
+ LOG(INFO) << "e4crypt_initialize_global_de";
- if (s_enabled) {
- LOG(INFO) << "Already enabled";
- return 0;
+ if (s_global_de_initialized) {
+ LOG(INFO) << "Already initialized";
+ return true;
}
std::string device_key;
- std::string device_key_path = std::string(path) + device_key_leaf;
- if (!android::vold::retrieveKey(device_key_path, kEmptyAuthentication, device_key)) {
+ if (path_exists(device_key_path)) {
+ if (!android::vold::retrieveKey(device_key_path,
+ kEmptyAuthentication, &device_key)) return false;
+ } else {
LOG(INFO) << "Creating new key";
- if (!random_key(device_key)) {
- return -1;
- }
-
- std::string key_temp = std::string(path) + device_key_temp;
- if (path_exists(key_temp)) {
- android::vold::destroyKey(key_temp);
- }
-
- if (!android::vold::storeKey(key_temp, kEmptyAuthentication, device_key)) return false;
- if (rename(key_temp.c_str(), device_key_path.c_str()) != 0) {
- PLOG(ERROR) << "Unable to move new key to location: "
- << device_key_path;
- return false;
- }
+ if (!random_key(&device_key)) return false;
+ if (!store_key(device_key_path, device_key_temp,
+ kEmptyAuthentication, device_key)) return false;
}
std::string device_key_ref;
- if (!install_key(device_key, device_key_ref)) {
+ if (!install_key(device_key, &device_key_ref)) {
LOG(ERROR) << "Failed to install device key";
- return -1;
+ return false;
}
std::string ref_filename = std::string("/data") + e4crypt_key_ref;
if (!android::base::WriteStringToFile(device_key_ref, ref_filename)) {
PLOG(ERROR) << "Cannot save key reference";
- return -1;
+ return false;
}
- s_enabled = true;
- return 0;
+ s_global_de_initialized = true;
+ return true;
}
-int e4crypt_init_user0() {
+bool e4crypt_init_user0() {
LOG(DEBUG) << "e4crypt_init_user0";
if (e4crypt_is_native()) {
- if (!prepare_dir(user_key_dir, 0700, AID_ROOT, AID_ROOT)) return -1;
- if (!prepare_dir(user_key_dir + "/ce", 0700, AID_ROOT, AID_ROOT)) return -1;
- if (!prepare_dir(user_key_dir + "/de", 0700, AID_ROOT, AID_ROOT)) return -1;
- auto de_path = get_de_key_path(0);
- auto ce_path = get_ce_key_path(0);
- if (!path_exists(de_path) || !path_exists(ce_path)) {
- if (path_exists(de_path)) {
- android::vold::destroyKey(de_path); // Ignore failure
- }
- if (path_exists(ce_path)) {
- android::vold::destroyKey(ce_path); // Ignore failure
- }
- if (!create_and_install_user_keys(0, false)) return -1;
+ if (!prepare_dir(user_key_dir, 0700, AID_ROOT, AID_ROOT)) return false;
+ if (!prepare_dir(user_key_dir + "/ce", 0700, AID_ROOT, AID_ROOT)) return false;
+ if (!prepare_dir(user_key_dir + "/de", 0700, AID_ROOT, AID_ROOT)) return false;
+ if (!path_exists(get_de_key_path(0))) {
+ if (!create_and_install_user_keys(0, false)) return false;
}
// TODO: switch to loading only DE_0 here once framework makes
// explicit calls to install DE keys for secondary users
- if (!load_all_de_keys()) return -1;
+ if (!load_all_de_keys()) return false;
}
// We can only safely prepare DE storage here, since CE keys are probably
// entangled with user credentials. The framework will always prepare CE
// storage once CE keys are installed.
- if (e4crypt_prepare_user_storage(nullptr, 0, 0, FLAG_STORAGE_DE) != 0) {
+ if (!e4crypt_prepare_user_storage(nullptr, 0, 0, FLAG_STORAGE_DE)) {
LOG(ERROR) << "Failed to prepare user 0 storage";
- return -1;
+ return false;
}
// If this is a non-FBE device that recently left an emulated mode,
e4crypt_unlock_user_key(0, 0, "!", "!");
}
- return 0;
+ return true;
}
-int e4crypt_vold_create_user_key(userid_t user_id, int serial, bool ephemeral) {
+bool e4crypt_vold_create_user_key(userid_t user_id, int serial, bool ephemeral) {
LOG(DEBUG) << "e4crypt_vold_create_user_key for " << user_id << " serial " << serial;
if (!e4crypt_is_native()) {
- return 0;
+ return true;
}
// FIXME test for existence of key that is not loaded yet
if (s_ce_key_raw_refs.count(user_id) != 0) {
- LOG(ERROR) << "Already exists, can't e4crypt_vold_create_user_key for "
- << user_id << " serial " << serial;
+ LOG(ERROR) << "Already exists, can't e4crypt_vold_create_user_key for " << user_id
+ << " serial " << serial;
// FIXME should we fail the command?
- return 0;
+ return true;
}
if (!create_and_install_user_keys(user_id, ephemeral)) {
- return -1;
+ return false;
}
- // TODO: create second key for user_de data
- return 0;
+ return true;
}
-static bool evict_key(const std::string &raw_ref) {
+static bool evict_key(const std::string& raw_ref) {
auto ref = keyname(raw_ref);
- auto key_serial = keyctl_search(e4crypt_keyring(), "logon", ref.c_str(), 0);
+ key_serial_t device_keyring;
+ if (!e4crypt_keyring(&device_keyring)) return false;
+ auto key_serial = keyctl_search(device_keyring, "logon", ref.c_str(), 0);
if (keyctl_revoke(key_serial) != 0) {
PLOG(ERROR) << "Failed to revoke key with serial " << key_serial << " ref " << ref;
return false;
return true;
}
-int e4crypt_destroy_user_key(userid_t user_id) {
+bool e4crypt_destroy_user_key(userid_t user_id) {
LOG(DEBUG) << "e4crypt_destroy_user_key(" << user_id << ")";
if (!e4crypt_is_native()) {
- return 0;
+ return true;
}
bool success = true;
s_ce_keys.erase(user_id);
std::string raw_ref;
- success &= lookup_key_ref(s_ce_key_raw_refs, user_id, raw_ref) && evict_key(raw_ref);
+ // If we haven't loaded the CE key, no need to evict it.
+ if (lookup_key_ref(s_ce_key_raw_refs, user_id, &raw_ref)) {
+ success &= evict_key(raw_ref);
+ }
s_ce_key_raw_refs.erase(user_id);
- success &= lookup_key_ref(s_de_key_raw_refs, user_id, raw_ref) && evict_key(raw_ref);
+ success &= lookup_key_ref(s_de_key_raw_refs, user_id, &raw_ref) && evict_key(raw_ref);
s_de_key_raw_refs.erase(user_id);
auto it = s_ephemeral_users.find(user_id);
if (it != s_ephemeral_users.end()) {
s_ephemeral_users.erase(it);
} else {
- success &= android::vold::destroyKey(get_ce_key_path(user_id));
+ for (auto const path: get_ce_key_paths(get_ce_key_directory_path(user_id))) {
+ success &= android::vold::destroyKey(path);
+ }
success &= android::vold::destroyKey(get_de_key_path(user_id));
}
- return success ? 0 : -1;
+ return success;
}
-static int emulated_lock(const std::string& path) {
+static bool emulated_lock(const std::string& path) {
if (chmod(path.c_str(), 0000) != 0) {
PLOG(ERROR) << "Failed to chmod " << path;
- return -1;
+ return false;
}
#if EMULATED_USES_SELINUX
if (setfilecon(path.c_str(), "u:object_r:storage_stub_file:s0") != 0) {
PLOG(WARNING) << "Failed to setfilecon " << path;
- return -1;
+ return false;
}
#endif
- return 0;
+ return true;
}
-static int emulated_unlock(const std::string& path, mode_t mode) {
+static bool emulated_unlock(const std::string& path, mode_t mode) {
if (chmod(path.c_str(), mode) != 0) {
PLOG(ERROR) << "Failed to chmod " << path;
// FIXME temporary workaround for b/26713622
- if (e4crypt_is_emulated()) return -1;
+ if (e4crypt_is_emulated()) return false;
}
#if EMULATED_USES_SELINUX
if (selinux_android_restorecon(path.c_str(), SELINUX_ANDROID_RESTORECON_FORCE) != 0) {
PLOG(WARNING) << "Failed to restorecon " << path;
// FIXME temporary workaround for b/26713622
- if (e4crypt_is_emulated()) return -1;
+ if (e4crypt_is_emulated()) return false;
}
#endif
- return 0;
+ return true;
}
-static bool parse_hex(const char *hex, std::string &result) {
+static bool parse_hex(const char* hex, std::string* result) {
if (strcmp("!", hex) == 0) {
- result = "";
+ *result = "";
return true;
}
- if (android::vold::HexToStr(hex, result) != 0) {
- LOG(ERROR) << "Invalid FBE hex string"; // Don't log the string for security reasons
+ if (android::vold::HexToStr(hex, *result) != 0) {
+ LOG(ERROR) << "Invalid FBE hex string"; // Don't log the string for security reasons
return false;
}
return true;
}
-int e4crypt_change_user_key(userid_t user_id, int serial,
- const char* token_hex, const char* old_secret_hex, const char* new_secret_hex) {
- LOG(DEBUG) << "e4crypt_change_user_key " << user_id << " serial=" << serial <<
- " token_present=" << (strcmp(token_hex, "!") != 0);
- if (!e4crypt_is_native()) return 0;
- if (s_ephemeral_users.count(user_id) != 0) return 0;
- std::string token, old_secret, new_secret;
- if (!parse_hex(token_hex, token)) return -1;
- if (!parse_hex(old_secret_hex, old_secret)) return -1;
- if (!parse_hex(new_secret_hex, new_secret)) return -1;
- auto auth = new_secret.empty()
- ? kEmptyAuthentication
- : android::vold::KeyAuthentication(token, new_secret);
+bool e4crypt_add_user_key_auth(userid_t user_id, int serial, const char* token_hex,
+ const char* secret_hex) {
+ LOG(DEBUG) << "e4crypt_add_user_key_auth " << user_id << " serial=" << serial
+ << " token_present=" << (strcmp(token_hex, "!") != 0);
+ if (!e4crypt_is_native()) return true;
+ if (s_ephemeral_users.count(user_id) != 0) return true;
+ std::string token, secret;
+ if (!parse_hex(token_hex, &token)) return false;
+ if (!parse_hex(secret_hex, &secret)) return false;
+ auto auth = secret.empty() ? kEmptyAuthentication
+ : android::vold::KeyAuthentication(token, secret);
auto it = s_ce_keys.find(user_id);
if (it == s_ce_keys.end()) {
LOG(ERROR) << "Key not loaded into memory, can't change for user " << user_id;
- return -1;
+ return false;
}
auto ce_key = it->second;
- auto ce_key_path = get_ce_key_path(user_id);
- android::vold::destroyKey(ce_key_path);
- if (!store_key(ce_key_path, auth, ce_key)) return -1;
- return 0;
+ auto const directory_path = get_ce_key_directory_path(user_id);
+ auto const paths = get_ce_key_paths(directory_path);
+ std::string ce_key_path;
+ if (!get_ce_key_new_path(directory_path, paths, &ce_key_path)) return false;
+ if (!store_key(ce_key_path, user_key_temp, auth, ce_key)) return false;
+ return true;
+}
+
+bool e4crypt_fixate_newest_user_key_auth(userid_t user_id) {
+ LOG(DEBUG) << "e4crypt_fixate_newest_user_key_auth " << user_id;
+ if (!e4crypt_is_native()) return true;
+ auto const directory_path = get_ce_key_directory_path(user_id);
+ auto const paths = get_ce_key_paths(directory_path);
+ if (paths.empty()) {
+ LOG(ERROR) << "No ce keys present, cannot fixate for user " << user_id;
+ return false;
+ }
+ fixate_user_ce_key(directory_path, paths[0], paths);
+ return true;
}
// TODO: rename to 'install' for consistency, and take flags to know which keys to install
-int e4crypt_unlock_user_key(userid_t user_id, int serial,
- const char* token_hex, const char* secret_hex) {
- LOG(DEBUG) << "e4crypt_unlock_user_key " << user_id << " serial=" << serial <<
- " token_present=" << (strcmp(token_hex, "!") != 0);
+bool e4crypt_unlock_user_key(userid_t user_id, int serial, const char* token_hex,
+ const char* secret_hex) {
+ LOG(DEBUG) << "e4crypt_unlock_user_key " << user_id << " serial=" << serial
+ << " token_present=" << (strcmp(token_hex, "!") != 0);
if (e4crypt_is_native()) {
if (s_ce_key_raw_refs.count(user_id) != 0) {
LOG(WARNING) << "Tried to unlock already-unlocked key for user " << user_id;
- return 0;
+ return true;
}
std::string token, secret;
- if (!parse_hex(token_hex, token)) return false;
- if (!parse_hex(secret_hex, secret)) return false;
+ if (!parse_hex(token_hex, &token)) return false;
+ if (!parse_hex(secret_hex, &secret)) return false;
android::vold::KeyAuthentication auth(token, secret);
if (!read_and_install_user_ce_key(user_id, auth)) {
LOG(ERROR) << "Couldn't read key for " << user_id;
- return -1;
+ return false;
}
} else {
// When in emulation mode, we just use chmod. However, we also
// unlock directories when not in emulation mode, to bring devices
// back into a known-good state.
- if (emulated_unlock(android::vold::BuildDataSystemCePath(user_id), 0771) ||
- emulated_unlock(android::vold::BuildDataMiscCePath(user_id), 01771) ||
- emulated_unlock(android::vold::BuildDataMediaPath(nullptr, user_id), 0770) ||
- emulated_unlock(android::vold::BuildDataUserPath(nullptr, user_id), 0771)) {
+ if (!emulated_unlock(android::vold::BuildDataSystemCePath(user_id), 0771) ||
+ !emulated_unlock(android::vold::BuildDataMiscCePath(user_id), 01771) ||
+ !emulated_unlock(android::vold::BuildDataMediaCePath(nullptr, user_id), 0770) ||
+ !emulated_unlock(android::vold::BuildDataUserCePath(nullptr, user_id), 0771)) {
LOG(ERROR) << "Failed to unlock user " << user_id;
- return -1;
+ return false;
}
}
- return 0;
+ return true;
}
// TODO: rename to 'evict' for consistency
-int e4crypt_lock_user_key(userid_t user_id) {
+bool e4crypt_lock_user_key(userid_t user_id) {
if (e4crypt_is_native()) {
// TODO: remove from kernel keyring
} else if (e4crypt_is_emulated()) {
// When in emulation mode, we just use chmod
- if (emulated_lock(android::vold::BuildDataSystemCePath(user_id)) ||
- emulated_lock(android::vold::BuildDataMiscCePath(user_id)) ||
- emulated_lock(android::vold::BuildDataMediaPath(nullptr, user_id)) ||
- emulated_lock(android::vold::BuildDataUserPath(nullptr, user_id))) {
- PLOG(ERROR) << "Failed to lock user " << user_id;
- return -1;
+ if (!emulated_lock(android::vold::BuildDataSystemCePath(user_id)) ||
+ !emulated_lock(android::vold::BuildDataMiscCePath(user_id)) ||
+ !emulated_lock(android::vold::BuildDataMediaCePath(nullptr, user_id)) ||
+ !emulated_lock(android::vold::BuildDataUserCePath(nullptr, user_id))) {
+ LOG(ERROR) << "Failed to lock user " << user_id;
+ return false;
}
}
- return 0;
+ return true;
}
-int e4crypt_prepare_user_storage(const char* volume_uuid, userid_t user_id,
- int serial, int flags) {
+bool e4crypt_prepare_user_storage(const char* volume_uuid, userid_t user_id, int serial,
+ int flags) {
LOG(DEBUG) << "e4crypt_prepare_user_storage for volume " << escape_null(volume_uuid)
- << ", user " << user_id << ", serial " << serial << ", flags " << flags;
+ << ", user " << user_id << ", serial " << serial << ", flags " << flags;
if (flags & FLAG_STORAGE_DE) {
+ // DE_sys key
+ auto system_legacy_path = android::vold::BuildDataSystemLegacyPath(user_id);
+ auto misc_legacy_path = android::vold::BuildDataMiscLegacyPath(user_id);
+ auto profiles_de_path = android::vold::BuildDataProfilesDePath(user_id);
+ auto foreign_de_path = android::vold::BuildDataProfilesForeignDexDePath(user_id);
+
+ // DE_n key
auto system_de_path = android::vold::BuildDataSystemDePath(user_id);
auto misc_de_path = android::vold::BuildDataMiscDePath(user_id);
auto user_de_path = android::vold::BuildDataUserDePath(volume_uuid, user_id);
- if (!prepare_dir(system_de_path, 0770, AID_SYSTEM, AID_SYSTEM)) return -1;
- if (!prepare_dir(misc_de_path, 01771, AID_SYSTEM, AID_MISC)) return -1;
- if (!prepare_dir(user_de_path, 0771, AID_SYSTEM, AID_SYSTEM)) return -1;
+ if (!prepare_dir(system_legacy_path, 0700, AID_SYSTEM, AID_SYSTEM)) return false;
+#if MANAGE_MISC_DIRS
+ if (!prepare_dir(misc_legacy_path, 0750, multiuser_get_uid(user_id, AID_SYSTEM),
+ multiuser_get_uid(user_id, AID_EVERYBODY))) return false;
+#endif
+ if (!prepare_dir(profiles_de_path, 0771, AID_SYSTEM, AID_SYSTEM)) return false;
+ if (!prepare_dir(foreign_de_path, 0773, AID_SYSTEM, AID_SYSTEM)) return false;
+
+ if (!prepare_dir(system_de_path, 0770, AID_SYSTEM, AID_SYSTEM)) return false;
+ if (!prepare_dir(misc_de_path, 01771, AID_SYSTEM, AID_MISC)) return false;
+ if (!prepare_dir(user_de_path, 0771, AID_SYSTEM, AID_SYSTEM)) return false;
- if (e4crypt_crypto_complete(DATA_MNT_POINT) == 0) {
+ // For now, FBE is only supported on internal storage
+ if (e4crypt_is_native() && volume_uuid == nullptr) {
std::string de_raw_ref;
- if (!lookup_key_ref(s_de_key_raw_refs, user_id, de_raw_ref)) return -1;
- if (!ensure_policy(de_raw_ref, system_de_path)) return -1;
- if (!ensure_policy(de_raw_ref, misc_de_path)) return -1;
- if (!ensure_policy(de_raw_ref, user_de_path)) return -1;
+ if (!lookup_key_ref(s_de_key_raw_refs, user_id, &de_raw_ref)) return false;
+ if (!ensure_policy(de_raw_ref, system_de_path)) return false;
+ if (!ensure_policy(de_raw_ref, misc_de_path)) return false;
+ if (!ensure_policy(de_raw_ref, user_de_path)) return false;
}
}
if (flags & FLAG_STORAGE_CE) {
+ // CE_n key
auto system_ce_path = android::vold::BuildDataSystemCePath(user_id);
auto misc_ce_path = android::vold::BuildDataMiscCePath(user_id);
- auto media_ce_path = android::vold::BuildDataMediaPath(volume_uuid, user_id);
- auto user_ce_path = android::vold::BuildDataUserPath(volume_uuid, user_id);
+ auto media_ce_path = android::vold::BuildDataMediaCePath(volume_uuid, user_id);
+ auto user_ce_path = android::vold::BuildDataUserCePath(volume_uuid, user_id);
- if (!prepare_dir(system_ce_path, 0770, AID_SYSTEM, AID_SYSTEM)) return -1;
- if (!prepare_dir(misc_ce_path, 01771, AID_SYSTEM, AID_MISC)) return -1;
- if (!prepare_dir(media_ce_path, 0770, AID_MEDIA_RW, AID_MEDIA_RW)) return -1;
- if (!prepare_dir(user_ce_path, 0771, AID_SYSTEM, AID_SYSTEM)) return -1;
+ if (!prepare_dir(system_ce_path, 0770, AID_SYSTEM, AID_SYSTEM)) return false;
+ if (!prepare_dir(misc_ce_path, 01771, AID_SYSTEM, AID_MISC)) return false;
+ if (!prepare_dir(media_ce_path, 0770, AID_MEDIA_RW, AID_MEDIA_RW)) return false;
+ if (!prepare_dir(user_ce_path, 0771, AID_SYSTEM, AID_SYSTEM)) return false;
- if (e4crypt_crypto_complete(DATA_MNT_POINT) == 0) {
+ // For now, FBE is only supported on internal storage
+ if (e4crypt_is_native() && volume_uuid == nullptr) {
std::string ce_raw_ref;
- if (!lookup_key_ref(s_ce_key_raw_refs, user_id, ce_raw_ref)) return -1;
- if (!ensure_policy(ce_raw_ref, system_ce_path)) return -1;
- if (!ensure_policy(ce_raw_ref, misc_ce_path)) return -1;
- if (!ensure_policy(ce_raw_ref, media_ce_path)) return -1;
- if (!ensure_policy(ce_raw_ref, user_ce_path)) return -1;
+ if (!lookup_key_ref(s_ce_key_raw_refs, user_id, &ce_raw_ref)) return false;
+ if (!ensure_policy(ce_raw_ref, system_ce_path)) return false;
+ if (!ensure_policy(ce_raw_ref, misc_ce_path)) return false;
+ if (!ensure_policy(ce_raw_ref, media_ce_path)) return false;
+ if (!ensure_policy(ce_raw_ref, user_ce_path)) return false;
+ }
+ }
+
+ return true;
+}
+
+bool e4crypt_destroy_user_storage(const char* volume_uuid, userid_t user_id, int flags) {
+ LOG(DEBUG) << "e4crypt_destroy_user_storage for volume " << escape_null(volume_uuid)
+ << ", user " << user_id << ", flags " << flags;
+ bool res = true;
+
+ if (flags & FLAG_STORAGE_DE) {
+ // DE_sys key
+ auto system_legacy_path = android::vold::BuildDataSystemLegacyPath(user_id);
+ auto misc_legacy_path = android::vold::BuildDataMiscLegacyPath(user_id);
+ auto profiles_de_path = android::vold::BuildDataProfilesDePath(user_id);
+ auto foreign_de_path = android::vold::BuildDataProfilesForeignDexDePath(user_id);
+
+ // DE_n key
+ auto system_de_path = android::vold::BuildDataSystemDePath(user_id);
+ auto misc_de_path = android::vold::BuildDataMiscDePath(user_id);
+ auto user_de_path = android::vold::BuildDataUserDePath(volume_uuid, user_id);
+
+ if (volume_uuid == nullptr) {
+ res &= destroy_dir(system_legacy_path);
+#if MANAGE_MISC_DIRS
+ res &= destroy_dir(misc_legacy_path);
+#endif
+ res &= destroy_dir(profiles_de_path);
+ res &= destroy_dir(foreign_de_path);
+ res &= destroy_dir(system_de_path);
+ res &= destroy_dir(misc_de_path);
+ }
+ res &= destroy_dir(user_de_path);
+ }
+
+ if (flags & FLAG_STORAGE_CE) {
+ // CE_n key
+ auto system_ce_path = android::vold::BuildDataSystemCePath(user_id);
+ auto misc_ce_path = android::vold::BuildDataMiscCePath(user_id);
+ auto media_ce_path = android::vold::BuildDataMediaCePath(volume_uuid, user_id);
+ auto user_ce_path = android::vold::BuildDataUserCePath(volume_uuid, user_id);
+
+ if (volume_uuid == nullptr) {
+ res &= destroy_dir(system_ce_path);
+ res &= destroy_dir(misc_ce_path);
}
+ res &= destroy_dir(media_ce_path);
+ res &= destroy_dir(user_ce_path);
}
- return 0;
+ return res;
}
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