resolve merge conflicts of 2b6f9ce823 to master.
Change-Id: I69f36f560334b11b099f2eb15999603dd2469d4f
diff --git a/Android.mk b/Android.mk
index 8c0771d..bea18b2 100644
--- a/Android.mk
+++ b/Android.mk
@@ -27,6 +27,8 @@
MoveTask.cpp \
Benchmark.cpp \
TrimTask.cpp \
+ Keymaster.cpp \
+ KeyStorage.cpp \
secontext.cpp \
common_c_includes := \
@@ -53,7 +55,8 @@
libutils \
libhardware \
libsoftkeymaster \
- libbase
+ libbase \
+ libkeymaster_messages \
common_static_libraries := \
libfs_mgr \
@@ -62,7 +65,7 @@
libsquashfs_utils \
libscrypt_static \
libmincrypt \
- libbatteryservice
+ libbatteryservice \
vold_conlyflags := -std=c11
vold_cflags := -Werror -Wall -Wno-missing-field-initializers -Wno-unused-variable -Wno-unused-parameter
@@ -127,7 +130,7 @@
LOCAL_CLANG := true
LOCAL_SRC_FILES:= secdiscard.cpp
LOCAL_MODULE:= secdiscard
-LOCAL_SHARED_LIBRARIES := libcutils
+LOCAL_SHARED_LIBRARIES := libbase
LOCAL_CFLAGS := $(vold_cflags)
LOCAL_CONLYFLAGS := $(vold_conlyflags)
diff --git a/AutoCloseFD.h b/AutoCloseFD.h
new file mode 100644
index 0000000..9b68469
--- /dev/null
+++ b/AutoCloseFD.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <string>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <android-base/logging.h>
+
+// File descriptor which is automatically closed when this object is destroyed.
+// Cannot be copied, since that would cause double-closes.
+class AutoCloseFD {
+public:
+ AutoCloseFD(const char *path, int flags = O_RDONLY, int mode = 0):
+ fd{TEMP_FAILURE_RETRY(open(path, flags | O_CLOEXEC, mode))} {}
+ AutoCloseFD(const std::string &path, int flags = O_RDONLY, int mode = 0):
+ AutoCloseFD(path.c_str(), flags, mode) {}
+ ~AutoCloseFD() {
+ if (fd != -1) {
+ int preserve_errno = errno;
+ if (close(fd) == -1) {
+ PLOG(ERROR) << "close(2) failed";
+ };
+ errno = preserve_errno;
+ }
+ }
+ AutoCloseFD(const AutoCloseFD&) = delete;
+ AutoCloseFD& operator=(const AutoCloseFD&) = delete;
+ explicit operator bool() {return fd != -1;}
+ int get() const {return fd;}
+private:
+ const int fd;
+};
+
diff --git a/CommandListener.cpp b/CommandListener.cpp
index 4a8ed75..edbb776 100644
--- a/CommandListener.cpp
+++ b/CommandListener.cpp
@@ -15,7 +15,9 @@
*/
#include <stdlib.h>
+#include <sys/mount.h>
#include <sys/socket.h>
+#include <sys/stat.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
@@ -27,6 +29,7 @@
#include <string.h>
#include <stdint.h>
#include <inttypes.h>
+#include <ctype.h>
#define LOG_TAG "VoldCmdListener"
@@ -44,8 +47,6 @@
#include "Process.h"
#include "Loop.h"
#include "Devmapper.h"
-#include "Ext4Crypt.h"
-#include "cryptfs.h"
#include "MoveTask.h"
#include "TrimTask.h"
@@ -59,6 +60,7 @@
registerCmd(new ObbCmd());
registerCmd(new StorageCmd());
registerCmd(new FstrimCmd());
+ registerCmd(new AppFuseCmd());
}
#if DUMP_ARGS
@@ -621,3 +623,143 @@
(new android::vold::TrimTask(flags))->start();
return sendGenericOkFail(cli, 0);
}
+
+static size_t kAppFuseMaxMountPointName = 32;
+
+static bool isValidAppFuseMountName(const std::string& name) {
+ if (name.size() > kAppFuseMaxMountPointName) {
+ return false;
+ }
+ for (size_t i = 0; i < name.size(); i++) {
+ if (!isalnum(name[i])) {
+ return false;
+ }
+ }
+ return true;
+}
+
+CommandListener::AppFuseCmd::AppFuseCmd() : VoldCommand("appfuse") {}
+
+int CommandListener::AppFuseCmd::runCommand(SocketClient *cli,
+ int argc,
+ char **argv) {
+ if (argc < 2) {
+ cli->sendMsg(
+ ResponseCode::CommandSyntaxError, "Missing argument", false);
+ return 0;
+ }
+
+ const std::string command(argv[1]);
+
+ if (command == "mount" && argc == 4) {
+ const uid_t uid = atoi(argv[2]);
+ const std::string name(argv[3]);
+
+ // Check mount point name.
+ if (!isValidAppFuseMountName(name)) {
+ return cli->sendMsg(
+ ResponseCode::CommandParameterError,
+ "Invalid mount point name.",
+ false);
+ }
+
+ // Create directories.
+ char path[PATH_MAX];
+ {
+ snprintf(path, PATH_MAX, "/mnt/appfuse/%d_%s", uid, name.c_str());
+ umount2(path, UMOUNT_NOFOLLOW | MNT_DETACH);
+ const int result = android::vold::PrepareDir(path, 0700, 0, 0);
+ if (result != 0) {
+ return sendGenericOkFail(cli, result);
+ }
+ }
+
+ // Open device FD.
+ const int device_fd = open("/dev/fuse", O_RDWR);
+ if (device_fd < 0) {
+ sendGenericOkFail(cli, device_fd);
+ return 0;
+ }
+
+ // Mount.
+ {
+ char opts[256];
+ snprintf(
+ opts,
+ sizeof(opts),
+ "fd=%i,"
+ "rootmode=40000,"
+ "default_permissions,"
+ "allow_other,"
+ "user_id=%d,group_id=%d",
+ device_fd,
+ uid,
+ uid);
+ // TODO: Make it bound mount in application namespace.
+ // TODO: Add context= option to opts.
+ const int result = mount(
+ "/dev/fuse", path, "fuse",
+ MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts);
+ if (result != 0) {
+ sendGenericOkFail(cli, 1);
+ return 0;
+ }
+ }
+
+ const int result = sendFd(cli, device_fd);
+ close(device_fd);
+ return result;
+ } else if (command == "unmount" && argc == 4) {
+ const uid_t uid = atoi(argv[2]);
+ const std::string name(argv[3]);
+
+ // Check mount point name.
+ if (!isValidAppFuseMountName(name)) {
+ return cli->sendMsg(
+ ResponseCode::CommandParameterError,
+ "Invalid mount point name.",
+ false);
+ }
+
+ // Unmount directory.
+ char path[PATH_MAX];
+ snprintf(path, PATH_MAX, "/mnt/appfuse/%d_%s", uid, name.c_str());
+ umount2(path, UMOUNT_NOFOLLOW | MNT_DETACH);
+
+ return sendGenericOkFail(cli, /* success */ 0);
+ }
+
+ return cli->sendMsg(
+ ResponseCode::CommandSyntaxError, "Unknown appfuse cmd", false);
+}
+
+int CommandListener::AppFuseCmd::sendFd(SocketClient *cli, int fd) {
+ struct iovec data;
+ char dataBuffer[128];
+ char controlBuffer[CMSG_SPACE(sizeof(int))];
+ struct msghdr message;
+
+ // Message.
+ memset(&message, 0, sizeof(struct msghdr));
+ message.msg_iov = &data;
+ message.msg_iovlen = 1;
+ message.msg_control = controlBuffer;
+ message.msg_controllen = CMSG_SPACE(sizeof(int));
+
+ // Data.
+ data.iov_base = dataBuffer;
+ data.iov_len = snprintf(dataBuffer,
+ sizeof(dataBuffer),
+ "200 %d AppFuse command succeeded",
+ cli->getCmdNum()) + 1;
+
+ // Control.
+ struct cmsghdr* const controlMessage = CMSG_FIRSTHDR(&message);
+ memset(controlBuffer, 0, CMSG_SPACE(sizeof(int)));
+ controlMessage->cmsg_level = SOL_SOCKET;
+ controlMessage->cmsg_type = SCM_RIGHTS;
+ controlMessage->cmsg_len = CMSG_LEN(sizeof(int));
+ *((int *) CMSG_DATA(controlMessage)) = fd;
+
+ return TEMP_FAILURE_RETRY(sendmsg(cli->getSocket(), &message, 0));
+}
diff --git a/CommandListener.h b/CommandListener.h
index 6ed099b..aede465 100644
--- a/CommandListener.h
+++ b/CommandListener.h
@@ -73,6 +73,15 @@
virtual ~FstrimCmd() {}
int runCommand(SocketClient *c, int argc, char ** argv);
};
+
+ class AppFuseCmd : public VoldCommand {
+ public:
+ AppFuseCmd();
+ virtual ~AppFuseCmd() {}
+ int runCommand(SocketClient *c, int argc, char ** argv);
+ private:
+ int sendFd(SocketClient *c, int fd);
+ };
};
#endif
diff --git a/CryptCommandListener.cpp b/CryptCommandListener.cpp
index 1babef7..2eac60e 100644
--- a/CryptCommandListener.cpp
+++ b/CryptCommandListener.cpp
@@ -16,6 +16,7 @@
#include <stdlib.h>
#include <sys/socket.h>
+#include <sys/stat.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>
@@ -28,9 +29,13 @@
#include <stdint.h>
#include <inttypes.h>
+#include <algorithm>
+
#define LOG_TAG "VoldCryptCmdListener"
+#include <android-base/logging.h>
#include <android-base/stringprintf.h>
+
#include <cutils/fs.h>
#include <cutils/log.h>
#include <cutils/sockets.h>
@@ -43,6 +48,7 @@
#include "ResponseCode.h"
#include "cryptfs.h"
#include "Ext4Crypt.h"
+#include "Utils.h"
#define DUMP_ARGS 0
@@ -110,6 +116,34 @@
}
}
+static char* parseNull(char* arg) {
+ if (strcmp(arg, "!") == 0) {
+ return nullptr;
+ } else {
+ return arg;
+ }
+}
+
+static bool check_argc(SocketClient *cli, const std::string &subcommand, int argc,
+ int expected, std::string usage) {
+ assert(expected >= 2);
+ if (expected == 2) {
+ assert(usage.empty());
+ } else {
+ assert(!usage.empty());
+ assert(std::count(usage.begin(), usage.end(), ' ') + 3 == expected);
+ }
+ if (argc == expected) {
+ return true;
+ }
+ auto message = std::string() + "Usage: cryptfs " + subcommand;
+ if (!usage.empty()) {
+ message += " " + usage;
+ }
+ cli->sendMsg(ResponseCode::CommandSyntaxError, message.c_str(), false);
+ return false;
+}
+
int CryptCommandListener::CryptfsCmd::runCommand(SocketClient *cli,
int argc, char **argv) {
if ((cli->getUid() != 0) && (cli->getUid() != AID_SYSTEM)) {
@@ -118,34 +152,26 @@
}
if (argc < 2) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Missing Argument", false);
+ cli->sendMsg(ResponseCode::CommandSyntaxError, "Missing subcommand", false);
return 0;
}
int rc = 0;
- if (!strcmp(argv[1], "checkpw")) {
- if (argc != 3) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Usage: cryptfs checkpw <passwd>", false);
- return 0;
- }
+ std::string subcommand(argv[1]);
+ if (subcommand == "checkpw") {
+ if (!check_argc(cli, subcommand, argc, 3, "<passwd>")) return 0;
dumpArgs(argc, argv, 2);
rc = cryptfs_check_passwd(argv[2]);
- } else if (!strcmp(argv[1], "restart")) {
- if (argc != 2) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Usage: cryptfs restart", false);
- return 0;
- }
+ } else if (subcommand == "restart") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
dumpArgs(argc, argv, -1);
rc = cryptfs_restart();
- } else if (!strcmp(argv[1], "cryptocomplete")) {
- if (argc != 2) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Usage: cryptfs cryptocomplete", false);
- return 0;
- }
+ } else if (subcommand == "cryptocomplete") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
dumpArgs(argc, argv, -1);
rc = cryptfs_crypto_complete();
- } else if (!strcmp(argv[1], "enablecrypto")) {
+ } else if (subcommand == "enablecrypto") {
const char* syntax = "Usage: cryptfs enablecrypto <wipe|inplace> "
"default|password|pin|pattern [passwd] [noui]";
@@ -215,15 +241,11 @@
Process::killProcessesWithOpenFiles(DATA_MNT_POINT, SIGKILL);
}
}
- } else if (!strcmp(argv[1], "enablefilecrypto")) {
- const char* syntax = "Usage: cryptfs enablefilecrypto";
- if (argc != 2) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, syntax, false);
- return 0;
- }
+ } else if (subcommand == "enablefilecrypto") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
dumpArgs(argc, argv, -1);
rc = cryptfs_enable_file();
- } else if (!strcmp(argv[1], "changepw")) {
+ } else if (subcommand == "changepw") {
const char* syntax = "Usage: cryptfs changepw "
"default|password|pin|pattern [newpasswd]";
const char* password;
@@ -242,21 +264,15 @@
}
SLOGD("cryptfs changepw %s {}", argv[2]);
rc = cryptfs_changepw(type, password);
- } else if (!strcmp(argv[1], "verifypw")) {
- if (argc != 3) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Usage: cryptfs verifypw <passwd>", false);
- return 0;
- }
+ } else if (subcommand == "verifypw") {
+ if (!check_argc(cli, subcommand, argc, 3, "<passwd>")) return 0;
SLOGD("cryptfs verifypw {}");
rc = cryptfs_verify_passwd(argv[2]);
- } else if (!strcmp(argv[1], "getfield")) {
+ } else if (subcommand == "getfield") {
+ if (!check_argc(cli, subcommand, argc, 3, "<fieldname>")) return 0;
char *valbuf;
int valbuf_len = PROPERTY_VALUE_MAX;
- if (argc != 3) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Usage: cryptfs getfield <fieldname>", false);
- return 0;
- }
dumpArgs(argc, argv, -1);
// Increase the buffer size until it is big enough for the field value stored.
@@ -277,18 +293,17 @@
cli->sendMsg(ResponseCode::CryptfsGetfieldResult, valbuf, false);
}
free(valbuf);
- } else if (!strcmp(argv[1], "setfield")) {
- if (argc != 4) {
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Usage: cryptfs setfield <fieldname> <value>", false);
- return 0;
- }
+ } else if (subcommand == "setfield") {
+ if (!check_argc(cli, subcommand, argc, 4, "<fieldname> <value>")) return 0;
dumpArgs(argc, argv, -1);
rc = cryptfs_setfield(argv[2], argv[3]);
- } else if (!strcmp(argv[1], "mountdefaultencrypted")) {
+ } else if (subcommand == "mountdefaultencrypted") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
SLOGD("cryptfs mountdefaultencrypted");
dumpArgs(argc, argv, -1);
rc = cryptfs_mount_default_encrypted();
- } else if (!strcmp(argv[1], "getpwtype")) {
+ } else if (subcommand == "getpwtype") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
SLOGD("cryptfs getpwtype");
dumpArgs(argc, argv, -1);
switch(cryptfs_get_password_type()) {
@@ -309,7 +324,8 @@
cli->sendMsg(ResponseCode::OpFailedStorageNotFound, "Error", false);
return 0;
}
- } else if (!strcmp(argv[1], "getpw")) {
+ } else if (subcommand == "getpw") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
SLOGD("cryptfs getpw");
dumpArgs(argc, argv, -1);
const char* password = cryptfs_get_password();
@@ -324,43 +340,55 @@
}
}
rc = -1;
- } else if (!strcmp(argv[1], "clearpw")) {
+ } else if (subcommand == "clearpw") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
SLOGD("cryptfs clearpw");
dumpArgs(argc, argv, -1);
cryptfs_clear_password();
rc = 0;
- } else if (!strcmp(argv[1], "setusercryptopolicies")) {
- if (argc != 3) {
- cli->sendMsg(ResponseCode::CommandSyntaxError,
- "Usage: cryptfs setusercryptopolicies <path>", false);
- return 0;
- }
- SLOGD("cryptfs setusercryptopolicies");
- dumpArgs(argc, argv, -1);
- rc = e4crypt_set_user_crypto_policies(argv[2]);
- } else if (!strcmp(argv[1], "createnewuserdir")) {
- if (argc != 4) {
- cli->sendMsg(ResponseCode::CommandSyntaxError,
- "Usage: cryptfs createnewuserdir <userHandle> <path>", false);
- return 0;
- }
+
+ } else if (subcommand == "isConvertibleToFBE") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
// ext4enc:TODO: send a CommandSyntaxError if argv[2] not an integer
- SLOGD("cryptfs createnewuserdir");
+ SLOGD("cryptfs isConvertibleToFBE");
dumpArgs(argc, argv, -1);
- rc = e4crypt_create_new_user_dir(argv[2], argv[3]);
- } else if (!strcmp(argv[1], "deleteuserkey")) {
- if (argc != 3) {
- cli->sendMsg(ResponseCode::CommandSyntaxError,
- "Usage: cryptfs deleteuserkey <userHandle>", false);
- return 0;
- }
- // ext4enc:TODO: send a CommandSyntaxError if argv[2] not an integer
- SLOGD("cryptfs deleteuserkey");
- dumpArgs(argc, argv, -1);
- rc = e4crypt_delete_user_key(argv[2]);
+ rc = cryptfs_isConvertibleToFBE();
+
+ } else if (subcommand == "init_user0") {
+ if (!check_argc(cli, subcommand, argc, 2, "")) return 0;
+ return sendGenericOkFail(cli, e4crypt_init_user0());
+
+ } else if (subcommand == "create_user_key") {
+ if (!check_argc(cli, subcommand, argc, 5, "<user> <serial> <ephemeral>")) return 0;
+ return sendGenericOkFail(cli,
+ e4crypt_vold_create_user_key(atoi(argv[2]),
+ atoi(argv[3]),
+ atoi(argv[4]) != 0));
+
+ } else if (subcommand == "destroy_user_key") {
+ if (!check_argc(cli, subcommand, argc, 3, "<user>")) return 0;
+ return sendGenericOkFail(cli, e4crypt_destroy_user_key(atoi(argv[2])));
+
+ } else if (subcommand == "unlock_user_key") {
+ if (!check_argc(cli, subcommand, argc, 5, "<user> <serial> <token>")) return 0;
+ return sendGenericOkFail(cli, e4crypt_unlock_user_key(
+ atoi(argv[2]), atoi(argv[3]), parseNull(argv[4])));
+
+ } else if (subcommand == "lock_user_key") {
+ if (!check_argc(cli, subcommand, argc, 3, "<user>")) return 0;
+ return sendGenericOkFail(cli, e4crypt_lock_user_key(atoi(argv[2])));
+
+ } else if (subcommand == "prepare_user_storage") {
+ if (!check_argc(cli, subcommand, argc, 6, "<uuid> <user> <serial> <ephemeral>")) return 0;
+ return sendGenericOkFail(cli,
+ e4crypt_prepare_user_storage(parseNull(argv[2]),
+ atoi(argv[3]),
+ atoi(argv[4]),
+ atoi(argv[5]) != 0));
+
} else {
dumpArgs(argc, argv, -1);
- cli->sendMsg(ResponseCode::CommandSyntaxError, "Unknown cryptfs cmd", false);
+ cli->sendMsg(ResponseCode::CommandSyntaxError, "Unknown cryptfs subcommand", false);
return 0;
}
diff --git a/EmulatedVolume.cpp b/EmulatedVolume.cpp
index 230fa8b..581c322 100644
--- a/EmulatedVolume.cpp
+++ b/EmulatedVolume.cpp
@@ -107,17 +107,21 @@
}
status_t EmulatedVolume::doUnmount() {
+ // Unmount the storage before we kill the FUSE process. If we kill
+ // the FUSE process first, most file system operations will return
+ // ENOTCONN until the unmount completes. This is an exotic and unusual
+ // error code and might cause broken behaviour in applications.
+ KillProcessesUsingPath(getPath());
+ ForceUnmount(mFuseDefault);
+ ForceUnmount(mFuseRead);
+ ForceUnmount(mFuseWrite);
+
if (mFusePid > 0) {
kill(mFusePid, SIGTERM);
TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, 0));
mFusePid = 0;
}
- KillProcessesUsingPath(getPath());
- ForceUnmount(mFuseDefault);
- ForceUnmount(mFuseRead);
- ForceUnmount(mFuseWrite);
-
rmdir(mFuseDefault.c_str());
rmdir(mFuseRead.c_str());
rmdir(mFuseWrite.c_str());
diff --git a/Ext4Crypt.cpp b/Ext4Crypt.cpp
index 0807c2c..72c79fa 100644
--- a/Ext4Crypt.cpp
+++ b/Ext4Crypt.cpp
@@ -1,11 +1,31 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
#include "Ext4Crypt.h"
+#include "KeyStorage.h"
+#include "Utils.h"
+
#include <iomanip>
#include <map>
-#include <fstream>
+#include <set>
#include <string>
#include <sstream>
+#include <stdio.h>
#include <errno.h>
#include <dirent.h>
#include <sys/mount.h>
@@ -14,6 +34,7 @@
#include <fcntl.h>
#include <cutils/properties.h>
#include <openssl/sha.h>
+#include <selinux/android.h>
#include <private/android_filesystem_config.h>
@@ -23,11 +44,29 @@
#include "ext4_crypt_init_extensions.h"
#define LOG_TAG "Ext4Crypt"
-#include "cutils/log.h"
+
+#define EMULATED_USES_SELINUX 0
+
+#include <cutils/fs.h>
+#include <cutils/log.h>
#include <cutils/klog.h>
+
#include <android-base/file.h>
+#include <android-base/logging.h>
#include <android-base/stringprintf.h>
+using android::base::StringPrintf;
+
+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);
+}
+
namespace {
// Key length in bits
const int key_length = 128;
@@ -37,6 +76,9 @@
// How long do we store passwords for?
const int password_max_age_seconds = 60;
+ 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";
+
// How is device encrypted
struct keys {
std::string master_key;
@@ -44,9 +86,13 @@
time_t expiry_time;
};
std::map<std::string, keys> s_key_store;
+ // 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;
- // ext4enc:TODO get these consts from somewhere good
- const int SHA512_LENGTH = 64;
+ // ext4enc:TODO get this const from somewhere good
const int EXT4_KEY_DESCRIPTOR_SIZE = 8;
// ext4enc:TODO Include structure from somewhere sensible
@@ -78,7 +124,7 @@
}
}
-static std::string e4crypt_install_key(const std::string &key);
+static bool install_key(const std::string &key, std::string &raw_ref);
static int put_crypt_ftr_and_key(const crypt_mnt_ftr& crypt_ftr,
UnencryptedProperties& props)
@@ -294,12 +340,12 @@
SHA512_Init(&c);
SHA512_Update(&c, key, length);
- unsigned char key_ref1[SHA512_LENGTH];
+ unsigned char key_ref1[SHA512_DIGEST_LENGTH];
SHA512_Final(key_ref1, &c);
SHA512_Init(&c);
- SHA512_Update(&c, key_ref1, SHA512_LENGTH);
- unsigned char key_ref2[SHA512_LENGTH];
+ SHA512_Update(&c, key_ref1, SHA512_DIGEST_LENGTH);
+ unsigned char key_ref2[SHA512_DIGEST_LENGTH];
SHA512_Final(key_ref2, &c);
return std::string((char*)key_ref2, EXT4_KEY_DESCRIPTOR_SIZE);
@@ -340,10 +386,11 @@
clock_gettime(CLOCK_BOOTTIME, &now);
s_key_store[path] = keys{master_key, password,
now.tv_sec + password_max_age_seconds};
- auto raw_ref = e4crypt_install_key(master_key);
- if (raw_ref.empty()) {
+ std::string raw_ref;
+ if (!install_key(master_key, raw_ref)) {
return -1;
}
+ SLOGD("Installed master key");
// Save reference to key so we can set policy later
if (!props.Set(properties::ref, raw_ref)) {
@@ -385,34 +432,28 @@
return keyctl_search(KEY_SPEC_SESSION_KEYRING, "keyring", "e4crypt", 0);
}
-static int e4crypt_install_key(const ext4_encryption_key &ext4_key, const std::string &ref)
+// 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();
- SLOGI("Found device_keyring - id is %d", device_keyring);
key_serial_t key_id = add_key("logon", ref.c_str(),
(void*)&ext4_key, sizeof(ext4_key),
device_keyring);
if (key_id == -1) {
- SLOGE("Failed to insert key into keyring with error %s",
- strerror(errno));
- return -1;
+ PLOG(ERROR) << "Failed to insert key into keyring " << device_keyring;
+ return false;
}
- SLOGI("Added key %d (%s) to keyring %d in process %d",
- key_id, ref.c_str(), device_keyring, getpid());
- return 0;
-}
-
-// Install password into global keyring
-// Return raw key reference for use in policy
-static std::string e4crypt_install_key(const std::string &key)
-{
- auto ext4_key = fill_key(key);
- auto raw_ref = generate_key_ref(ext4_key.raw, ext4_key.size);
- auto ref = keyname(raw_ref);
- if (e4crypt_install_key(ext4_key, ref) == -1) {
- return "";
- }
- return raw_ref;
+ LOG(INFO) << "Added key " << key_id << " (" << ref << ") to keyring "
+ << device_keyring << " in process " << getpid();
+ return true;
}
int e4crypt_restart(const char* path)
@@ -509,92 +550,114 @@
.Set(fieldname, std::string(value)) ? 0 : -1;
}
-static std::string get_key_path(
- const char *mount_path,
- const char *user_handle)
-{
- // ext4enc:TODO get the path properly
- auto key_dir = android::base::StringPrintf("%s/misc/vold/user_keys",
- mount_path);
- if (mkdir(key_dir.c_str(), 0700) < 0 && errno != EEXIST) {
- SLOGE("Unable to create %s (%s)", key_dir.c_str(), strerror(errno));
- return "";
- }
- return key_dir + "/" + user_handle;
+static std::string get_de_key_path(userid_t user_id) {
+ return StringPrintf("%s/de/%d", user_key_dir.c_str(), user_id);
}
-// ext4enc:TODO this can't be the only place keys are read from /dev/urandom
-// we should unite those places.
-static std::string e4crypt_get_key(
- const std::string &key_path,
- bool create_if_absent)
-{
- std::string content;
- if (android::base::ReadFileToString(key_path, &content)) {
- if (content.size() != key_length/8) {
- SLOGE("Wrong size key %zu in %s", content.size(), key_path.c_str());
- return "";
- }
- return content;
- }
- if (!create_if_absent) {
- SLOGE("No key found in %s", key_path.c_str());
- return "";
- }
- std::ifstream urandom("/dev/urandom");
- if (!urandom) {
- SLOGE("Unable to open /dev/urandom (%s)", strerror(errno));
- return "";
- }
- char key_bytes[key_length / 8];
- errno = 0;
- urandom.read(key_bytes, sizeof(key_bytes));
- if (!urandom) {
- SLOGE("Unable to read key from /dev/urandom (%s)", strerror(errno));
- return "";
- }
- std::string key(key_bytes, sizeof(key_bytes));
- if (!android::base::WriteStringToFile(key, key_path)) {
- SLOGE("Unable to write key to %s (%s)",
- key_path.c_str(), strerror(errno));
- return "";
- }
- return key;
+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 int e4crypt_set_user_policy(const char *mount_path, const char *user_handle,
- const char *path, bool create_if_absent)
+static bool read_and_install_key(const std::string &key_path, std::string &raw_ref)
{
- SLOGD("e4crypt_set_user_policy for %s", user_handle);
- auto user_key = e4crypt_get_key(
- get_key_path(mount_path, user_handle),
- create_if_absent);
- if (user_key.empty()) {
- return -1;
- }
- auto raw_ref = e4crypt_install_key(user_key);
- if (raw_ref.empty()) {
- return -1;
- }
- return do_policy_set(path, raw_ref.c_str(), raw_ref.size());
+ std::string key;
+ if (!android::vold::retrieveKey(key_path, key)) return false;
+ if (!install_key(key, raw_ref)) return false;
+ return true;
}
-int e4crypt_create_new_user_dir(const char *user_handle, const char *path) {
- SLOGD("e4crypt_create_new_user_dir(\"%s\", \"%s\")", user_handle, path);
- if (mkdir(path, S_IRWXU | S_IRWXG | S_IXOTH) < 0) {
- return -1;
+static bool read_and_install_user_ce_key(userid_t user_id)
+{
+ if (s_ce_key_raw_refs.count(user_id) != 0) return true;
+ const auto key_path = get_ce_key_path(user_id);
+ std::string raw_ref;
+ if (!read_and_install_key(key_path, raw_ref)) return false;
+ s_ce_key_raw_refs[user_id] = 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) {
+ LOG(DEBUG) << "Preparing: " << dir;
+ if (fs_prepare_dir(dir.c_str(), mode, uid, gid) != 0) {
+ PLOG(ERROR) << "Failed to prepare " << dir;
+ return false;
}
- if (chmod(path, S_IRWXU | S_IRWXG | S_IXOTH) < 0) {
- return -1;
+ return true;
+}
+
+static bool random_key(std::string &key) {
+ if (android::vold::ReadRandomBytes(key_length / 8, key) != 0) {
+ // TODO status_t plays badly with PLOG, fix it.
+ LOG(ERROR) << "Random read failed";
+ return false;
}
- if (chown(path, AID_SYSTEM, AID_SYSTEM) < 0) {
- return -1;
+ return true;
+}
+
+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 std::string &key) {
+ if (path_exists(key_path)) {
+ LOG(ERROR) << "Already exists, cannot create key at: " << key_path;
+ return false;
}
- if (e4crypt_crypto_complete(DATA_MNT_POINT) == 0) {
- // ext4enc:TODO handle errors from this.
- e4crypt_set_user_policy(DATA_MNT_POINT, user_handle, path, true);
+ if (path_exists(user_key_temp)) {
+ android::vold::destroyKey(user_key_temp);
}
- return 0;
+ if (!android::vold::storeKey(user_key_temp, key)) return false;
+ if (rename(user_key_temp.c_str(), key_path.c_str()) != 0) {
+ PLOG(ERROR) << "Unable to move new key to location: " << key_path;
+ return false;
+ }
+ LOG(DEBUG) << "Created key " << key_path;
+ return true;
+}
+
+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 (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), 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), ce_key)) return false;
+ }
+ std::string de_raw_ref;
+ 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;
+ 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) {
+ 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;
+ return true;
+}
+
+static bool set_policy(const std::string &raw_ref, const std::string& path) {
+ if (do_policy_set(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) {
@@ -605,67 +668,213 @@
return true;
}
-int e4crypt_set_user_crypto_policies(const char *dir)
-{
- if (e4crypt_crypto_complete(DATA_MNT_POINT) != 0) {
- return 0;
- }
- SLOGD("e4crypt_set_user_crypto_policies");
- std::unique_ptr<DIR, int(*)(DIR*)> dirp(opendir(dir), closedir);
+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);
if (!dirp) {
- SLOGE("Unable to read directory %s, error %s\n",
- dir, strerror(errno));
- return -1;
+ PLOG(ERROR) << "Unable to read de key directory";
+ return false;
}
for (;;) {
- struct dirent *result = readdir(dirp.get());
- if (!result) {
- // ext4enc:TODO check errno
+ errno = 0;
+ auto entry = readdir(dirp.get());
+ if (!entry) {
+ if (errno) {
+ PLOG(ERROR) << "Unable to read de key directory";
+ return false;
+ }
break;
}
- if (result->d_type != DT_DIR || !is_numeric(result->d_name)) {
- continue; // skips user 0, which is a symlink
+ if (entry->d_type != DT_DIR || !is_numeric(entry->d_name)) {
+ LOG(DEBUG) << "Skipping non-de-key " << entry->d_name;
+ continue;
}
- auto user_dir = std::string() + dir + "/" + result->d_name;
- // ext4enc:TODO don't hardcode /data
- if (e4crypt_set_user_policy("/data", result->d_name,
- user_dir.c_str(), false)) {
- // ext4enc:TODO If this function fails, stop the boot: we must
- // deliver on promised encryption.
- SLOGE("Unable to set policy on %s\n", user_dir.c_str());
+ userid_t user_id = atoi(entry->d_name);
+ if (s_de_key_raw_refs.count(user_id) == 0) {
+ std::string raw_ref;
+ if (!read_and_install_key(de_dir + "/" + entry->d_name, raw_ref)) return false;
+ s_de_key_raw_refs[user_id] = raw_ref;
+ LOG(DEBUG) << "Installed de key for user " << user_id;
+ }
+ }
+ // ext4enc:TODO: go through all DE directories, ensure that all user dirs have the
+ // correct policy set on them, and that no rogue ones exist.
+ return true;
+}
+
+int 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 (!load_all_de_keys()) return -1;
+ }
+ // Ignore failures. FIXME this is horrid
+ // FIXME: we need an idempotent policy-setting call, which simply verifies the
+ // policy is already set on a second run, even if the directory is nonempty.
+ // Then we need to call it all the time.
+ e4crypt_prepare_user_storage(nullptr, 0, 0, false);
+ return 0;
+}
+
+int 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;
+ }
+ // 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;
+ // FIXME should we fail the command?
+ return 0;
+ }
+ if (!create_and_install_user_keys(user_id, ephemeral)) {
+ return -1;
+ }
+ // TODO: create second key for user_de data
+ return 0;
+}
+
+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);
+ if (keyctl_revoke(key_serial) != 0) {
+ PLOG(ERROR) << "Failed to revoke key with serial " << key_serial << " ref " << ref;
+ return false;
+ }
+ LOG(DEBUG) << "Revoked key with serial " << key_serial << " ref " << ref;
+ return true;
+}
+
+int e4crypt_destroy_user_key(userid_t user_id) {
+ LOG(DEBUG) << "e4crypt_destroy_user_key(" << user_id << ")";
+ if (!e4crypt_is_native()) {
+ return 0;
+ }
+ bool success = true;
+ std::string raw_ref;
+ success &= lookup_key_ref(s_ce_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);
+ 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));
+ success &= android::vold::destroyKey(get_de_key_path(user_id));
+ }
+ return success ? 0 : -1;
+}
+
+static int emulated_lock(const std::string& path) {
+ if (chmod(path.c_str(), 0000) != 0) {
+ PLOG(ERROR) << "Failed to chmod " << path;
+ return -1;
+ }
+#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;
+ }
+#endif
+ return 0;
+}
+
+static int 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 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;
+ }
+#endif
+ return 0;
+}
+
+int e4crypt_unlock_user_key(userid_t user_id, int serial, const char* token) {
+ LOG(DEBUG) << "e4crypt_unlock_user_key " << user_id << " " << (token != nullptr);
+ if (e4crypt_is_native()) {
+ if (!read_and_install_user_ce_key(user_id)) {
+ LOG(ERROR) << "Couldn't read key for " << user_id;
+ return -1;
+ }
+ } 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::BuildDataMediaPath(nullptr, user_id), 0770) ||
+ emulated_unlock(android::vold::BuildDataUserPath(nullptr, user_id), 0771)) {
+ LOG(ERROR) << "Failed to unlock user " << user_id;
+ return -1;
}
}
return 0;
}
-int e4crypt_delete_user_key(const char *user_handle) {
- SLOGD("e4crypt_delete_user_key(\"%s\")", user_handle);
- auto key_path = get_key_path(DATA_MNT_POINT, user_handle);
- auto key = e4crypt_get_key(key_path, false);
- auto ext4_key = fill_key(key);
- auto ref = keyname(generate_key_ref(ext4_key.raw, ext4_key.size));
- auto key_serial = keyctl_search(e4crypt_keyring(), "logon", ref.c_str(), 0);
- if (keyctl_revoke(key_serial) == 0) {
- SLOGD("Revoked key with serial %ld ref %s\n", key_serial, ref.c_str());
+int 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::BuildDataMediaPath(nullptr, user_id)) ||
+ emulated_lock(android::vold::BuildDataUserPath(nullptr, user_id))) {
+ PLOG(ERROR) << "Failed to lock user " << user_id;
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+int e4crypt_prepare_user_storage(const char* volume_uuid,
+ userid_t user_id,
+ int serial,
+ bool ephemeral) {
+ if (volume_uuid) {
+ LOG(DEBUG) << "e4crypt_prepare_user_storage " << volume_uuid << " " << user_id;
} else {
- SLOGE("Failed to revoke key with serial %ld ref %s: %s\n",
- key_serial, ref.c_str(), strerror(errno));
+ LOG(DEBUG) << "e4crypt_prepare_user_storage, null volume " << user_id;
}
- int pid = fork();
- if (pid < 0) {
- SLOGE("Unable to fork: %s", strerror(errno));
- return -1;
+ auto system_ce_path = android::vold::BuildDataSystemCePath(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 user_de_path = android::vold::BuildDataUserDePath(volume_uuid, user_id);
+
+ // FIXME: should this be 0770 or 0700?
+ if (!prepare_dir(system_ce_path, 0770, AID_SYSTEM, AID_SYSTEM)) 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(user_de_path, 0771, AID_SYSTEM, AID_SYSTEM)) return -1;
+
+ if (e4crypt_crypto_complete(DATA_MNT_POINT) == 0) {
+ std::string ce_raw_ref, de_raw_ref;
+ if (!lookup_key_ref(s_ce_key_raw_refs, user_id, ce_raw_ref)) return -1;
+ if (!lookup_key_ref(s_de_key_raw_refs, user_id, de_raw_ref)) return -1;
+ if (!set_policy(ce_raw_ref, system_ce_path)) return -1;
+ if (!set_policy(ce_raw_ref, media_ce_path)) return -1;
+ if (!set_policy(ce_raw_ref, user_ce_path)) return -1;
+ if (!set_policy(de_raw_ref, user_de_path)) return -1;
+ // FIXME I thought there were more DE directories than this
}
- if (pid == 0) {
- SLOGD("Forked for secdiscard");
- execl("/system/bin/secdiscard",
- "/system/bin/secdiscard",
- key_path.c_str(),
- NULL);
- SLOGE("Unable to launch secdiscard on %s: %s\n", key_path.c_str(),
- strerror(errno));
- exit(-1);
- }
- // ext4enc:TODO reap the zombie
+
return 0;
}
diff --git a/Ext4Crypt.h b/Ext4Crypt.h
index f5c2871..9005f4a 100644
--- a/Ext4Crypt.h
+++ b/Ext4Crypt.h
@@ -1,11 +1,28 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
#include <stddef.h>
#include <sys/cdefs.h>
+#include <cutils/multiuser.h>
+
__BEGIN_DECLS
// General functions
int e4crypt_enable(const char* path);
-int e4crypt_main(int argc, char* argv[]);
int e4crypt_change_password(const char* path, int crypt_type,
const char* password);
int e4crypt_crypto_complete(const char* path);
@@ -18,8 +35,17 @@
char* value, size_t len);
int e4crypt_set_field(const char* path, const char* fieldname,
const char* value);
-int e4crypt_set_user_crypto_policies(const char *path);
-int e4crypt_create_new_user_dir(const char *user_handle, const char *path);
-int e4crypt_delete_user_key(const char *user_handle);
+
+int e4crypt_init_user0();
+int e4crypt_vold_create_user_key(userid_t user_id, int serial, bool ephemeral);
+int e4crypt_destroy_user_key(userid_t user_id);
+
+int e4crypt_unlock_user_key(userid_t user_id, int serial, const char* token);
+int e4crypt_lock_user_key(userid_t user_id);
+
+int e4crypt_prepare_user_storage(const char* volume_uuid,
+ userid_t user_id,
+ int serial,
+ bool ephemeral);
__END_DECLS
diff --git a/KeyStorage.cpp b/KeyStorage.cpp
new file mode 100644
index 0000000..070b79d
--- /dev/null
+++ b/KeyStorage.cpp
@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "KeyStorage.h"
+
+#include "Keymaster.h"
+#include "Utils.h"
+
+#include <vector>
+
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <openssl/sha.h>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+
+#include <keymaster/authorization_set.h>
+
+namespace android {
+namespace vold {
+
+static constexpr size_t AES_KEY_BYTES = 32;
+static constexpr size_t GCM_NONCE_BYTES = 12;
+static constexpr size_t GCM_MAC_BYTES = 16;
+// FIXME: better name than "secdiscardable" sought!
+static constexpr size_t SECDISCARDABLE_BYTES = 1<<14;
+
+static const char* kRmPath = "/system/bin/rm";
+static const char* kSecdiscardPath = "/system/bin/secdiscard";
+static const char* kFn_keymaster_key_blob = "keymaster_key_blob";
+static const char* kFn_encrypted_key = "encrypted_key";
+static const char* kFn_secdiscardable = "secdiscardable";
+
+static bool checkSize(const std::string& kind, size_t actual, size_t expected) {
+ if (actual != expected) {
+ LOG(ERROR) << "Wrong number of bytes in " << kind << ", expected " << expected
+ << " got " << actual;
+ return false;
+ }
+ return true;
+}
+
+static std::string hashSecdiscardable(const std::string &secdiscardable) {
+ SHA512_CTX c;
+
+ SHA512_Init(&c);
+ // Personalise the hashing by introducing a fixed prefix.
+ // Hashing applications should use personalization except when there is a
+ // specific reason not to; see section 4.11 of https://www.schneier.com/skein1.3.pdf
+ std::string secdiscardableHashingPrefix = "Android secdiscardable SHA512";
+ secdiscardableHashingPrefix.resize(SHA512_CBLOCK);
+ SHA512_Update(&c, secdiscardableHashingPrefix.data(), secdiscardableHashingPrefix.size());
+ SHA512_Update(&c, secdiscardable.data(), secdiscardable.size());
+ std::string res(SHA512_DIGEST_LENGTH, '\0');
+ SHA512_Final(reinterpret_cast<uint8_t *>(&res[0]), &c);
+ return res;
+}
+
+static bool generateKeymasterKey(Keymaster &keymaster,
+ const keymaster::AuthorizationSet &extraParams,
+ std::string &key) {
+ auto params = keymaster::AuthorizationSetBuilder()
+ .AesEncryptionKey(AES_KEY_BYTES * 8)
+ .Authorization(keymaster::TAG_BLOCK_MODE, KM_MODE_GCM)
+ .Authorization(keymaster::TAG_MIN_MAC_LENGTH, GCM_MAC_BYTES * 8)
+ .Authorization(keymaster::TAG_PADDING, KM_PAD_NONE)
+ .Authorization(keymaster::TAG_NO_AUTH_REQUIRED) // FIXME integrate with gatekeeper
+ .build();
+ params.push_back(extraParams);
+ return keymaster.generateKey(params, key);
+}
+
+static bool encryptWithKeymasterKey(
+ Keymaster &keymaster,
+ const std::string &key,
+ const keymaster::AuthorizationSet &extraParams,
+ const std::string &message,
+ std::string &ciphertext) {
+ // FIXME fix repetition
+ auto params = keymaster::AuthorizationSetBuilder()
+ .Authorization(keymaster::TAG_BLOCK_MODE, KM_MODE_GCM)
+ .Authorization(keymaster::TAG_MAC_LENGTH, GCM_MAC_BYTES * 8)
+ .Authorization(keymaster::TAG_PADDING, KM_PAD_NONE)
+ .build();
+ params.push_back(extraParams);
+ keymaster::AuthorizationSet outParams;
+ auto opHandle = keymaster.begin(KM_PURPOSE_ENCRYPT, key, params, outParams);
+ if (!opHandle) return false;
+ keymaster_blob_t nonceBlob;
+ if (!outParams.GetTagValue(keymaster::TAG_NONCE, &nonceBlob)) {
+ LOG(ERROR) << "GCM encryption but no nonce generated";
+ return false;
+ }
+ // nonceBlob here is just a pointer into existing data, must not be freed
+ std::string nonce(reinterpret_cast<const char *>(nonceBlob.data), nonceBlob.data_length);
+ if (!checkSize("nonce", nonce.size(), GCM_NONCE_BYTES)) return false;
+ std::string body;
+ if (!opHandle.updateCompletely(message, body)) return false;
+
+ std::string mac;
+ if (!opHandle.finishWithOutput(mac)) return false;
+ if (!checkSize("mac", mac.size(), GCM_MAC_BYTES)) return false;
+ ciphertext = nonce + body + mac;
+ return true;
+}
+
+static bool decryptWithKeymasterKey(
+ Keymaster &keymaster, const std::string &key,
+ const keymaster::AuthorizationSet &extraParams,
+ const std::string &ciphertext,
+ std::string &message) {
+ auto nonce = ciphertext.substr(0, GCM_NONCE_BYTES);
+ auto bodyAndMac = ciphertext.substr(GCM_NONCE_BYTES);
+ // FIXME fix repetition
+ auto params = addStringParam(keymaster::AuthorizationSetBuilder(), keymaster::TAG_NONCE, nonce)
+ .Authorization(keymaster::TAG_BLOCK_MODE, KM_MODE_GCM)
+ .Authorization(keymaster::TAG_MAC_LENGTH, GCM_MAC_BYTES * 8)
+ .Authorization(keymaster::TAG_PADDING, KM_PAD_NONE)
+ .build();
+ params.push_back(extraParams);
+
+ auto opHandle = keymaster.begin(KM_PURPOSE_DECRYPT, key, params);
+ if (!opHandle) return false;
+ if (!opHandle.updateCompletely(bodyAndMac, message)) return false;
+ if (!opHandle.finish()) return false;
+ return true;
+}
+
+static bool readFileToString(const std::string &filename, std::string &result) {
+ if (!android::base::ReadFileToString(filename, &result)) {
+ PLOG(ERROR) << "Failed to read from " << filename;
+ return false;
+ }
+ return true;
+}
+
+static bool writeStringToFile(const std::string &payload, const std::string &filename) {
+ if (!android::base::WriteStringToFile(payload, filename)) {
+ PLOG(ERROR) << "Failed to write to " << filename;
+ return false;
+ }
+ return true;
+}
+
+bool storeKey(const std::string &dir, const std::string &key) {
+ if (TEMP_FAILURE_RETRY(mkdir(dir.c_str(), 0700)) == -1) {
+ PLOG(ERROR) << "key mkdir " << dir;
+ return false;
+ }
+ std::string secdiscardable;
+ if (ReadRandomBytes(SECDISCARDABLE_BYTES, secdiscardable) != OK) {
+ // TODO status_t plays badly with PLOG, fix it.
+ LOG(ERROR) << "Random read failed";
+ return false;
+ }
+ if (!writeStringToFile(secdiscardable, dir + "/" + kFn_secdiscardable)) return false;
+ auto extraParams = addStringParam(keymaster::AuthorizationSetBuilder(),
+ keymaster::TAG_APPLICATION_ID, hashSecdiscardable(secdiscardable)).build();
+ Keymaster keymaster;
+ if (!keymaster) return false;
+ std::string kmKey;
+ if (!generateKeymasterKey(keymaster, extraParams, kmKey)) return false;
+ std::string encryptedKey;
+ if (!encryptWithKeymasterKey(
+ keymaster, kmKey, extraParams, key, encryptedKey)) return false;
+ if (!writeStringToFile(kmKey, dir + "/" + kFn_keymaster_key_blob)) return false;
+ if (!writeStringToFile(encryptedKey, dir + "/" + kFn_encrypted_key)) return false;
+ return true;
+}
+
+bool retrieveKey(const std::string &dir, std::string &key) {
+ std::string secdiscardable;
+ if (!readFileToString(dir + "/" + kFn_secdiscardable, secdiscardable)) return false;
+ auto extraParams = addStringParam(keymaster::AuthorizationSetBuilder(),
+ keymaster::TAG_APPLICATION_ID, hashSecdiscardable(secdiscardable)).build();
+ std::string kmKey;
+ if (!readFileToString(dir + "/" + kFn_keymaster_key_blob, kmKey)) return false;
+ std::string encryptedMessage;
+ if (!readFileToString(dir + "/" + kFn_encrypted_key, encryptedMessage)) return false;
+ Keymaster keymaster;
+ if (!keymaster) return false;
+ return decryptWithKeymasterKey(keymaster, kmKey, extraParams, encryptedMessage, key);
+}
+
+static bool deleteKey(const std::string &dir) {
+ std::string kmKey;
+ if (!readFileToString(dir + "/" + kFn_keymaster_key_blob, kmKey)) return false;
+ Keymaster keymaster;
+ if (!keymaster) return false;
+ if (!keymaster.deleteKey(kmKey)) return false;
+ return true;
+}
+
+static bool secdiscardSecdiscardable(const std::string &dir) {
+ if (ForkExecvp(std::vector<std::string> {
+ kSecdiscardPath, "--", dir + "/" + kFn_secdiscardable}) != 0) {
+ LOG(ERROR) << "secdiscard failed";
+ return false;
+ }
+ return true;
+}
+
+static bool recursiveDeleteKey(const std::string &dir) {
+ if (ForkExecvp(std::vector<std::string> {
+ kRmPath, "-rf", dir}) != 0) {
+ LOG(ERROR) << "recursive delete failed";
+ return false;
+ }
+ return true;
+}
+
+bool destroyKey(const std::string &dir) {
+ bool success = true;
+ // Try each thing, even if previous things failed.
+ success &= deleteKey(dir);
+ success &= secdiscardSecdiscardable(dir);
+ success &= recursiveDeleteKey(dir);
+ return success;
+}
+
+} // namespace vold
+} // namespace android
diff --git a/KeyStorage.h b/KeyStorage.h
new file mode 100644
index 0000000..a35349c
--- /dev/null
+++ b/KeyStorage.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_VOLD_KEYSTORAGE_H
+#define ANDROID_VOLD_KEYSTORAGE_H
+
+#include <string>
+
+namespace android {
+namespace vold {
+
+// Create a directory at the named path, and store "key" in it,
+// in such a way that it can only be retrieved via Keymaster and
+// can be securely deleted.
+// It's safe to move/rename the directory after creation.
+bool storeKey(const std::string &dir, const std::string &key);
+
+// Retrieve the key from the named directory.
+bool retrieveKey(const std::string &dir, std::string &key);
+
+// Securely destroy the key stored in the named directory and delete the directory.
+bool destroyKey(const std::string &dir);
+
+} // namespace vold
+} // namespace android
+
+#endif
diff --git a/Keymaster.cpp b/Keymaster.cpp
new file mode 100644
index 0000000..0fde8fa
--- /dev/null
+++ b/Keymaster.cpp
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Keymaster.h"
+
+#include <android-base/logging.h>
+
+namespace android {
+namespace vold {
+
+bool KeymasterOperation::updateCompletely(
+ const std::string &input,
+ std::string &output) {
+ output.clear();
+ auto it = input.begin();
+ while (it != input.end()) {
+ size_t toRead = static_cast<size_t>(input.end() - it);
+ keymaster_blob_t inputBlob {reinterpret_cast<const uint8_t *>(&*it), toRead};
+ keymaster_blob_t outputBlob;
+ size_t inputConsumed;
+ auto error = mDevice->update(mDevice, mOpHandle,
+ nullptr, &inputBlob, &inputConsumed, nullptr, &outputBlob);
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "update failed, code " << error;
+ mDevice = nullptr;
+ return false;
+ }
+ output.append(reinterpret_cast<const char *>(outputBlob.data), outputBlob.data_length);
+ free(const_cast<uint8_t *>(outputBlob.data));
+ if (inputConsumed > toRead) {
+ LOG(ERROR) << "update reported too much input consumed";
+ mDevice = nullptr;
+ return false;
+ }
+ it += inputConsumed;
+ }
+ return true;
+}
+
+bool KeymasterOperation::finish() {
+ auto error = mDevice->finish(mDevice, mOpHandle,
+ nullptr, nullptr, nullptr, nullptr);
+ mDevice = nullptr;
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "finish failed, code " << error;
+ return false;
+ }
+ return true;
+}
+
+bool KeymasterOperation::finishWithOutput(std::string &output) {
+ keymaster_blob_t outputBlob;
+ auto error = mDevice->finish(mDevice, mOpHandle,
+ nullptr, nullptr, nullptr, &outputBlob);
+ mDevice = nullptr;
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "finish failed, code " << error;
+ return false;
+ }
+ output.assign(reinterpret_cast<const char *>(outputBlob.data), outputBlob.data_length);
+ free(const_cast<uint8_t *>(outputBlob.data));
+ return true;
+}
+
+Keymaster::Keymaster() {
+ mDevice = nullptr;
+ const hw_module_t *module;
+ int ret = hw_get_module_by_class(KEYSTORE_HARDWARE_MODULE_ID, NULL, &module);
+ if (ret != 0) {
+ LOG(ERROR) << "hw_get_module_by_class returned " << ret;
+ return;
+ }
+ // TODO: This will need to be updated to support keymaster2.
+ if (module->module_api_version != KEYMASTER_MODULE_API_VERSION_1_0) {
+ LOG(ERROR) << "module_api_version is " << module->module_api_version;
+ return;
+ }
+ ret = keymaster1_open(module, &mDevice);
+ if (ret != 0) {
+ LOG(ERROR) << "keymaster1_open returned " << ret;
+ mDevice = nullptr;
+ return;
+ }
+}
+
+bool Keymaster::generateKey(
+ const keymaster::AuthorizationSet &inParams,
+ std::string &key) {
+ keymaster_key_blob_t keyBlob;
+ auto error = mDevice->generate_key(mDevice, &inParams, &keyBlob, nullptr);
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "generate_key failed, code " << error;
+ return false;
+ }
+ key.assign(reinterpret_cast<const char *>(keyBlob.key_material), keyBlob.key_material_size);
+ return true;
+}
+
+bool Keymaster::deleteKey(const std::string &key) {
+ if (mDevice->delete_key == nullptr) return true;
+ keymaster_key_blob_t keyBlob { reinterpret_cast<const uint8_t *>(key.data()), key.size() };
+ auto error = mDevice->delete_key(mDevice, &keyBlob);
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "delete_key failed, code " << error;
+ return false;
+ }
+ return true;
+}
+
+KeymasterOperation Keymaster::begin(
+ keymaster_purpose_t purpose,
+ const std::string &key,
+ const keymaster::AuthorizationSet &inParams,
+ keymaster::AuthorizationSet &outParams) {
+ keymaster_key_blob_t keyBlob { reinterpret_cast<const uint8_t *>(key.data()), key.size() };
+ keymaster_operation_handle_t mOpHandle;
+ keymaster_key_param_set_t outParams_set;
+ auto error = mDevice->begin(mDevice, purpose,
+ &keyBlob, &inParams, &outParams_set, &mOpHandle);
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "begin failed, code " << error;
+ return KeymasterOperation(nullptr, mOpHandle);
+ }
+ outParams.Clear();
+ outParams.push_back(outParams_set);
+ keymaster_free_param_set(&outParams_set);
+ return KeymasterOperation(mDevice, mOpHandle);
+}
+
+KeymasterOperation Keymaster::begin(
+ keymaster_purpose_t purpose,
+ const std::string &key,
+ const keymaster::AuthorizationSet &inParams) {
+ keymaster_key_blob_t keyBlob { reinterpret_cast<const uint8_t *>(key.data()), key.size() };
+ keymaster_operation_handle_t mOpHandle;
+ auto error = mDevice->begin(mDevice, purpose,
+ &keyBlob, &inParams, nullptr, &mOpHandle);
+ if (error != KM_ERROR_OK) {
+ LOG(ERROR) << "begin failed, code " << error;
+ return KeymasterOperation(nullptr, mOpHandle);
+ }
+ return KeymasterOperation(mDevice, mOpHandle);
+}
+
+} // namespace vold
+} // namespace android
diff --git a/Keymaster.h b/Keymaster.h
new file mode 100644
index 0000000..003baa6
--- /dev/null
+++ b/Keymaster.h
@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_VOLD_KEYMASTER1_H
+#define ANDROID_VOLD_KEYMASTER1_H
+
+#include <string>
+
+#include <hardware/hardware.h>
+#include <hardware/keymaster1.h>
+
+#include <keymaster/authorization_set.h>
+
+namespace android {
+namespace vold {
+
+using namespace keymaster;
+
+// C++ wrappers to the keymaster1 C interface.
+// This is tailored to the needs of KeyStorage, but could be extended to be
+// a more general interface.
+
+
+// Wrapper for a keymaster_operation_handle_t representing an
+// ongoing Keymaster operation. Aborts the operation
+// in the destructor if it is unfinished. Methods log failures
+// to LOG(ERROR).
+class KeymasterOperation {
+public:
+ ~KeymasterOperation() { if (mDevice) mDevice->abort(mDevice, mOpHandle); }
+ // Is this instance valid? This is false if creation fails, and becomes
+ // false on finish or if an update fails.
+ explicit operator bool() {return mDevice != nullptr;}
+ // Call "update" repeatedly until all of the input is consumed, and
+ // concatenate the output. Return true on success.
+ bool updateCompletely(const std::string &input, std::string &output);
+ // Finish; pass nullptr for the "output" param.
+ bool finish();
+ // Finish and write the output to this string.
+ bool finishWithOutput(std::string &output);
+ // Move constructor
+ KeymasterOperation(KeymasterOperation&& rhs) {
+ mOpHandle = rhs.mOpHandle;
+ mDevice = rhs.mDevice;
+ rhs.mDevice = nullptr;
+ }
+private:
+ KeymasterOperation(keymaster1_device_t *d, keymaster_operation_handle_t h):
+ mDevice {d}, mOpHandle {h} {}
+ keymaster1_device_t *mDevice;
+ keymaster_operation_handle_t mOpHandle;
+ DISALLOW_COPY_AND_ASSIGN(KeymasterOperation);
+ friend class Keymaster;
+};
+
+// Wrapper for a keymaster1_device_t representing an open connection
+// to the keymaster, which is closed in the destructor.
+class Keymaster {
+public:
+ Keymaster();
+ ~Keymaster() { if (mDevice) keymaster1_close(mDevice); }
+ // false if we failed to open the keymaster device.
+ explicit operator bool() {return mDevice != nullptr;}
+ // Generate a key in the keymaster from the given params.
+ bool generateKey(const AuthorizationSet &inParams, std::string &key);
+ // If the keymaster supports it, permanently delete a key.
+ bool deleteKey(const std::string &key);
+ // Begin a new cryptographic operation, collecting output parameters.
+ KeymasterOperation begin(
+ keymaster_purpose_t purpose,
+ const std::string &key,
+ const AuthorizationSet &inParams,
+ AuthorizationSet &outParams);
+ // Begin a new cryptographic operation; don't collect output parameters.
+ KeymasterOperation begin(
+ keymaster_purpose_t purpose,
+ const std::string &key,
+ const AuthorizationSet &inParams);
+private:
+ keymaster1_device_t *mDevice;
+ DISALLOW_COPY_AND_ASSIGN(Keymaster);
+};
+
+template <keymaster_tag_t Tag>
+inline AuthorizationSetBuilder& addStringParam(AuthorizationSetBuilder &¶ms,
+ TypedTag<KM_BYTES, Tag> tag, const std::string& val) {
+ return params.Authorization(tag, val.data(), val.size());
+}
+
+} // namespace vold
+} // namespace android
+
+#endif
diff --git a/PrivateVolume.cpp b/PrivateVolume.cpp
index a106481..21746b2 100644
--- a/PrivateVolume.cpp
+++ b/PrivateVolume.cpp
@@ -158,6 +158,7 @@
// Verify that common directories are ready to roll
if (PrepareDir(mPath + "/app", 0771, AID_SYSTEM, AID_SYSTEM) ||
PrepareDir(mPath + "/user", 0711, AID_SYSTEM, AID_SYSTEM) ||
+ PrepareDir(mPath + "/user_de", 0711, AID_SYSTEM, AID_SYSTEM) ||
PrepareDir(mPath + "/media", 0770, AID_MEDIA_RW, AID_MEDIA_RW) ||
PrepareDir(mPath + "/media/0", 0770, AID_MEDIA_RW, AID_MEDIA_RW) ||
PrepareDir(mPath + "/local", 0751, AID_ROOT, AID_ROOT) ||
diff --git a/Utils.cpp b/Utils.cpp
index e4f473a..aba3a53 100644
--- a/Utils.cpp
+++ b/Utils.cpp
@@ -547,10 +547,61 @@
return res;
}
+static bool isValidFilename(const std::string& name) {
+ if (name.empty() || (name == ".") || (name == "..")
+ || (name.find('/') != std::string::npos)) {
+ return false;
+ } else {
+ return true;
+ }
+}
+
std::string BuildKeyPath(const std::string& partGuid) {
return StringPrintf("%s/expand_%s.key", kKeyPath, partGuid.c_str());
}
+std::string BuildDataSystemCePath(userid_t userId) {
+ // TODO: unify with installd path generation logic
+ std::string data(BuildDataPath(nullptr));
+ return StringPrintf("%s/system_ce/%u", data.c_str(), userId);
+}
+
+std::string BuildDataPath(const char* volumeUuid) {
+ // TODO: unify with installd path generation logic
+ if (volumeUuid == nullptr) {
+ return "/data";
+ } else {
+ CHECK(isValidFilename(volumeUuid));
+ return StringPrintf("/mnt/expand/%s", volumeUuid);
+ }
+}
+
+std::string BuildDataMediaPath(const char* volumeUuid, userid_t userId) {
+ // TODO: unify with installd path generation logic
+ std::string data(BuildDataPath(volumeUuid));
+ return StringPrintf("%s/media/%u", data.c_str(), userId);
+}
+
+std::string BuildDataUserPath(const char* volumeUuid, userid_t userId) {
+ // TODO: unify with installd path generation logic
+ std::string data(BuildDataPath(volumeUuid));
+ if (volumeUuid == nullptr) {
+ if (userId == 0) {
+ return StringPrintf("%s/data", data.c_str());
+ } else {
+ return StringPrintf("%s/user/%u", data.c_str(), userId);
+ }
+ } else {
+ return StringPrintf("%s/user/%u", data.c_str(), userId);
+ }
+}
+
+std::string BuildDataUserDePath(const char* volumeUuid, userid_t userId) {
+ // TODO: unify with installd path generation logic
+ std::string data(BuildDataPath(volumeUuid));
+ return StringPrintf("%s/user_de/%u", data.c_str(), userId);
+}
+
dev_t GetDevice(const std::string& path) {
struct stat sb;
if (stat(path.c_str(), &sb)) {
diff --git a/Utils.h b/Utils.h
index 228727a..0a74af7 100644
--- a/Utils.h
+++ b/Utils.h
@@ -18,6 +18,7 @@
#define ANDROID_VOLD_UTILS_H
#include <utils/Errors.h>
+#include <cutils/multiuser.h>
#include <selinux/selinux.h>
#include <vector>
@@ -93,6 +94,13 @@
std::string BuildKeyPath(const std::string& partGuid);
+std::string BuildDataSystemCePath(userid_t userid);
+
+std::string BuildDataPath(const char* volumeUuid);
+std::string BuildDataMediaPath(const char* volumeUuid, userid_t userid);
+std::string BuildDataUserPath(const char* volumeUuid, userid_t userid);
+std::string BuildDataUserDePath(const char* volumeUuid, userid_t userid);
+
dev_t GetDevice(const std::string& path);
std::string DefaultFstabPath();
diff --git a/VolumeManager.cpp b/VolumeManager.cpp
old mode 100755
new mode 100644
diff --git a/cryptfs.c b/cryptfs.c
index 7ca05b0..c1020cd 100644
--- a/cryptfs.c
+++ b/cryptfs.c
@@ -83,6 +83,10 @@
#define DEFAULT_PASSWORD "default_password"
+#define CRYPTO_BLOCK_DEVICE "userdata"
+
+#define BREADCRUMB_FILE "/data/misc/vold/convert_fde"
+
#define EXT4_FS 1
#define F2FS_FS 2
@@ -190,6 +194,11 @@
keymaster0_device_t *keymaster0_dev = 0;
keymaster1_device_t *keymaster1_dev = 0;
+ if (ftr->keymaster_blob_size) {
+ SLOGI("Already have key");
+ return 0;
+ }
+
if (keymaster_init(&keymaster0_dev, &keymaster1_dev)) {
SLOGE("Failed to init keymaster");
return -1;
@@ -599,6 +608,16 @@
return rc;
}
+/* Set sha256 checksum in structure */
+static void set_ftr_sha(struct crypt_mnt_ftr *crypt_ftr)
+{
+ SHA256_CTX c;
+ SHA256_Init(&c);
+ memset(crypt_ftr->sha256, 0, sizeof(crypt_ftr->sha256));
+ SHA256_Update(&c, crypt_ftr, sizeof(*crypt_ftr));
+ SHA256_Final(crypt_ftr->sha256, &c);
+}
+
/* key or salt can be NULL, in which case just skip writing that value. Useful to
* update the failed mount count but not change the key.
*/
@@ -614,6 +633,8 @@
char *fname = NULL;
struct stat statbuf;
+ set_ftr_sha(crypt_ftr);
+
if (get_crypt_ftr_info(&fname, &starting_off)) {
SLOGE("Unable to get crypt_ftr_info\n");
return -1;
@@ -656,6 +677,14 @@
}
+static bool check_ftr_sha(const struct crypt_mnt_ftr *crypt_ftr)
+{
+ struct crypt_mnt_ftr copy;
+ memcpy(©, crypt_ftr, sizeof(copy));
+ set_ftr_sha(©);
+ return memcmp(copy.sha256, crypt_ftr->sha256, sizeof(copy.sha256)) == 0;
+}
+
static inline int unix_read(int fd, void* buff, int len)
{
return TEMP_FAILURE_RETRY(read(fd, buff, len));
@@ -2052,13 +2081,41 @@
int rc;
rc = check_unmounted_and_get_ftr(&crypt_ftr);
- if (rc)
+ if (rc) {
+ SLOGE("Could not get footer");
return rc;
+ }
rc = test_mount_encrypted_fs(&crypt_ftr, passwd,
- DATA_MNT_POINT, "userdata");
+ DATA_MNT_POINT, CRYPTO_BLOCK_DEVICE);
+ if (rc) {
+ SLOGE("Password did not match");
+ return rc;
+ }
- if (rc == 0 && crypt_ftr.crypt_type != CRYPT_TYPE_DEFAULT) {
+ if (crypt_ftr.flags & CRYPT_FORCE_COMPLETE) {
+ // Here we have a default actual password but a real password
+ // we must test against the scrypted value
+ // First, we must delete the crypto block device that
+ // test_mount_encrypted_fs leaves behind as a side effect
+ delete_crypto_blk_dev(CRYPTO_BLOCK_DEVICE);
+ rc = test_mount_encrypted_fs(&crypt_ftr, DEFAULT_PASSWORD,
+ DATA_MNT_POINT, CRYPTO_BLOCK_DEVICE);
+ if (rc) {
+ SLOGE("Default password did not match on reboot encryption");
+ return rc;
+ }
+
+ crypt_ftr.flags &= ~CRYPT_FORCE_COMPLETE;
+ put_crypt_ftr_and_key(&crypt_ftr);
+ rc = cryptfs_changepw(crypt_ftr.crypt_type, passwd);
+ if (rc) {
+ SLOGE("Could not change password on reboot encryption");
+ return rc;
+ }
+ }
+
+ if (crypt_ftr.crypt_type != CRYPT_TYPE_DEFAULT) {
cryptfs_clear_password();
password = strdup(passwd);
struct timespec now;
@@ -2931,6 +2988,7 @@
char key_loc[PROPERTY_VALUE_MAX];
int num_vols;
off64_t previously_encrypted_upto = 0;
+ bool rebootEncryption = false;
if (!strcmp(howarg, "wipe")) {
how = CRYPTO_ENABLE_WIPE;
@@ -2941,21 +2999,33 @@
goto error_unencrypted;
}
- /* See if an encryption was underway and interrupted */
if (how == CRYPTO_ENABLE_INPLACE
- && get_crypt_ftr_and_key(&crypt_ftr) == 0
- && (crypt_ftr.flags & CRYPT_ENCRYPTION_IN_PROGRESS)) {
- previously_encrypted_upto = crypt_ftr.encrypted_upto;
- crypt_ftr.encrypted_upto = 0;
- crypt_ftr.flags &= ~CRYPT_ENCRYPTION_IN_PROGRESS;
+ && get_crypt_ftr_and_key(&crypt_ftr) == 0) {
+ if (crypt_ftr.flags & CRYPT_ENCRYPTION_IN_PROGRESS) {
+ /* An encryption was underway and was interrupted */
+ previously_encrypted_upto = crypt_ftr.encrypted_upto;
+ crypt_ftr.encrypted_upto = 0;
+ crypt_ftr.flags &= ~CRYPT_ENCRYPTION_IN_PROGRESS;
- /* At this point, we are in an inconsistent state. Until we successfully
- complete encryption, a reboot will leave us broken. So mark the
- encryption failed in case that happens.
- On successfully completing encryption, remove this flag */
- crypt_ftr.flags |= CRYPT_INCONSISTENT_STATE;
+ /* At this point, we are in an inconsistent state. Until we successfully
+ complete encryption, a reboot will leave us broken. So mark the
+ encryption failed in case that happens.
+ On successfully completing encryption, remove this flag */
+ crypt_ftr.flags |= CRYPT_INCONSISTENT_STATE;
- put_crypt_ftr_and_key(&crypt_ftr);
+ put_crypt_ftr_and_key(&crypt_ftr);
+ } else if (crypt_ftr.flags & CRYPT_FORCE_ENCRYPTION) {
+ if (!check_ftr_sha(&crypt_ftr)) {
+ memset(&crypt_ftr, 0, sizeof(crypt_ftr));
+ put_crypt_ftr_and_key(&crypt_ftr);
+ goto error_unencrypted;
+ }
+
+ /* Doing a reboot-encryption*/
+ crypt_ftr.flags &= ~CRYPT_FORCE_ENCRYPTION;
+ crypt_ftr.flags |= CRYPT_FORCE_COMPLETE;
+ rebootEncryption = true;
+ }
}
property_get("ro.crypto.state", encrypted_state, "");
@@ -3015,13 +3085,23 @@
SLOGE("Failed to unmount all vold managed devices");
}
- /* Now unmount the /data partition. */
- if (wait_and_unmount(DATA_MNT_POINT, false)) {
- goto error_unencrypted;
+ /* no_ui means we are being called from init, not settings.
+ Now we always reboot from settings, so !no_ui means reboot
+ */
+ bool onlyCreateHeader = false;
+ if (!no_ui) {
+ /* Try fallback, which is to reboot and try there */
+ onlyCreateHeader = true;
+ FILE* breadcrumb = fopen(BREADCRUMB_FILE, "we");
+ if (breadcrumb == 0) {
+ SLOGE("Failed to create breadcrumb file");
+ goto error_shutting_down;
+ }
+ fclose(breadcrumb);
}
/* Do extra work for a better UX when doing the long inplace encryption */
- if (how == CRYPTO_ENABLE_INPLACE) {
+ if (how == CRYPTO_ENABLE_INPLACE && !onlyCreateHeader) {
/* Now that /data is unmounted, we need to mount a tmpfs
* /data, set a property saying we're doing inplace encryption,
* and restart the framework.
@@ -3048,7 +3128,7 @@
/* Start the actual work of making an encrypted filesystem */
/* Initialize a crypt_mnt_ftr for the partition */
- if (previously_encrypted_upto == 0) {
+ if (previously_encrypted_upto == 0 && !rebootEncryption) {
if (cryptfs_init_crypt_mnt_ftr(&crypt_ftr)) {
goto error_shutting_down;
}
@@ -3063,7 +3143,11 @@
complete encryption, a reboot will leave us broken. So mark the
encryption failed in case that happens.
On successfully completing encryption, remove this flag */
- crypt_ftr.flags |= CRYPT_INCONSISTENT_STATE;
+ if (onlyCreateHeader) {
+ crypt_ftr.flags |= CRYPT_FORCE_ENCRYPTION;
+ } else {
+ crypt_ftr.flags |= CRYPT_INCONSISTENT_STATE;
+ }
crypt_ftr.crypt_type = crypt_type;
#ifndef CONFIG_HW_DISK_ENCRYPTION
strlcpy((char *)crypt_ftr.crypto_type_name, "aes-cbc-essiv:sha256", MAX_CRYPTO_TYPE_NAME_LEN);
@@ -3084,11 +3168,21 @@
#endif
/* Make an encrypted master key */
- if (create_encrypted_random_key(passwd, crypt_ftr.master_key, crypt_ftr.salt, &crypt_ftr)) {
+ if (create_encrypted_random_key(onlyCreateHeader ? DEFAULT_PASSWORD : passwd,
+ crypt_ftr.master_key, crypt_ftr.salt, &crypt_ftr)) {
SLOGE("Cannot create encrypted master key\n");
goto error_shutting_down;
}
+ /* Replace scrypted intermediate key if we are preparing for a reboot */
+ if (onlyCreateHeader) {
+ unsigned char fake_master_key[KEY_LEN_BYTES];
+ unsigned char encrypted_fake_master_key[KEY_LEN_BYTES];
+ memset(fake_master_key, 0, sizeof(fake_master_key));
+ encrypt_master_key(passwd, crypt_ftr.salt, fake_master_key,
+ encrypted_fake_master_key, &crypt_ftr);
+ }
+
/* Write the key to the end of the partition */
put_crypt_ftr_and_key(&crypt_ftr);
@@ -3107,7 +3201,12 @@
}
}
- if (how == CRYPTO_ENABLE_INPLACE && !no_ui) {
+ if (onlyCreateHeader) {
+ sleep(2);
+ cryptfs_reboot(reboot);
+ }
+
+ if (how == CRYPTO_ENABLE_INPLACE && (!no_ui || rebootEncryption)) {
/* startup service classes main and late_start */
property_set("vold.decrypt", "trigger_restart_min_framework");
SLOGD("Just triggered restart_min_framework\n");
@@ -3121,7 +3220,7 @@
decrypt_master_key(passwd, decrypted_master_key, &crypt_ftr, 0, 0);
create_crypto_blk_dev(&crypt_ftr, decrypted_master_key, real_blkdev, crypto_blkdev,
- "userdata");
+ CRYPTO_BLOCK_DEVICE);
/* If we are continuing, check checksums match */
rc = 0;
@@ -3154,7 +3253,7 @@
}
/* Undo the dm-crypt mapping whether we succeed or not */
- delete_crypto_blk_dev("userdata");
+ delete_crypto_blk_dev(CRYPTO_BLOCK_DEVICE);
if (! rc) {
/* Success */
@@ -3177,8 +3276,16 @@
/* default encryption - continue first boot sequence */
property_set("ro.crypto.state", "encrypted");
release_wake_lock(lockid);
- cryptfs_check_passwd(DEFAULT_PASSWORD);
- cryptfs_restart_internal(1);
+ if (rebootEncryption && crypt_ftr.crypt_type != CRYPT_TYPE_DEFAULT) {
+ // Bring up cryptkeeper that will check the password and set it
+ property_set("vold.decrypt", "trigger_shutdown_framework");
+ sleep(2);
+ property_set("vold.encrypt_progress", "");
+ cryptfs_trigger_restart_min_framework();
+ } else {
+ cryptfs_check_passwd(DEFAULT_PASSWORD);
+ cryptfs_restart_internal(1);
+ }
return 0;
} else {
sleep(2); /* Give the UI a chance to show 100% progress */
@@ -3729,6 +3836,12 @@
return e4crypt_enable(DATA_MNT_POINT);
}
+int cryptfs_isConvertibleToFBE()
+{
+ struct fstab_rec* rec = fs_mgr_get_entry_for_mount_point(fstab, DATA_MNT_POINT);
+ return fs_mgr_is_convertible_to_fbe(rec) ? 1 : 0;
+}
+
int cryptfs_create_default_ftr(struct crypt_mnt_ftr* crypt_ftr, __attribute__((unused))int key_length)
{
if (cryptfs_init_crypt_mnt_ftr(crypt_ftr)) {
diff --git a/cryptfs.h b/cryptfs.h
index fd6f3da..033767f 100644
--- a/cryptfs.h
+++ b/cryptfs.h
@@ -52,6 +52,16 @@
correctly marked partial encryption */
#define CRYPT_DATA_CORRUPT 0x8 /* Set when encryption is fine, but the
underlying volume is corrupt */
+#define CRYPT_FORCE_ENCRYPTION 0x10 /* Set when it is time to encrypt this
+ volume on boot. Everything in this
+ structure is set up correctly as
+ though device is encrypted except
+ that the master key is encrypted with the
+ default password. */
+#define CRYPT_FORCE_COMPLETE 0x20 /* Set when the above encryption cycle is
+ complete. On next cryptkeeper entry, match
+ the password. If it matches fix the master
+ key and remove this flag. */
/* Allowed values for type in the structure below */
#define CRYPT_TYPE_PASSWORD 0 /* master_key is encrypted with a password
@@ -94,7 +104,7 @@
__le32 keysize; /* in bytes */
__le32 crypt_type; /* how master_key is encrypted. Must be a
* CRYPT_TYPE_XXX value */
- __le64 fs_size; /* Size of the encrypted fs, in 512 byte sectors */
+ __le64 fs_size; /* Size of the encrypted fs, in 512 byte sectors */
__le32 failed_decrypt_count; /* count of # of failed attempts to decrypt and
mount, set to 0 on successful mount */
unsigned char crypto_type_name[MAX_CRYPTO_TYPE_NAME_LEN]; /* The type of encryption
@@ -145,6 +155,12 @@
then we will be OK.
*/
unsigned char scrypted_intermediate_key[SCRYPT_LEN];
+
+ /* sha of this structure with this element set to zero
+ Used when encrypting on reboot to validate structure before doing something
+ fatal
+ */
+ unsigned char sha256[SHA256_DIGEST_LENGTH];
};
/* Persistant data that should be available before decryption.
@@ -231,6 +247,7 @@
int cryptfs_get_password_type(void);
const char* cryptfs_get_password(void);
void cryptfs_clear_password(void);
+ int cryptfs_isConvertibleToFBE(void);
// Functions for file encryption to use to inherit our encryption logic
int cryptfs_create_default_ftr(struct crypt_mnt_ftr* ftr, int key_length);
@@ -238,6 +255,7 @@
unsigned char* master_key);
int cryptfs_set_password(struct crypt_mnt_ftr* ftr, const char* password,
const unsigned char* master_key);
+
#ifdef __cplusplus
}
#endif
diff --git a/fs/F2fs.cpp b/fs/F2fs.cpp
index 84d27c4..0d12b07 100644
--- a/fs/F2fs.cpp
+++ b/fs/F2fs.cpp
@@ -43,7 +43,7 @@
status_t Check(const std::string& source) {
std::vector<std::string> cmd;
cmd.push_back(kFsckPath);
- cmd.push_back("-f");
+ cmd.push_back("-a");
cmd.push_back(source);
// f2fs devices are currently always trusted
diff --git a/main.cpp b/main.cpp
index 9cbcf88..6d94818 100644
--- a/main.cpp
+++ b/main.cpp
@@ -18,6 +18,7 @@
#include "VolumeManager.h"
#include "CommandListener.h"
#include "CryptCommandListener.h"
+#include "Ext4Crypt.h"
#include "NetlinkManager.h"
#include "cryptfs.h"
#include "sehandle.h"
diff --git a/secdiscard.cpp b/secdiscard.cpp
index 3f4ab2e..5c12cdd 100644
--- a/secdiscard.cpp
+++ b/secdiscard.cpp
@@ -14,7 +14,9 @@
* limitations under the License.
*/
+#include <memory>
#include <string>
+#include <vector>
#include <stdio.h>
#include <stdlib.h>
@@ -24,213 +26,184 @@
#include <fcntl.h>
#include <linux/fs.h>
#include <linux/fiemap.h>
+#include <mntent.h>
-#define LOG_TAG "secdiscard"
-#include "cutils/log.h"
+#include <android-base/logging.h>
-// Deliberately limit ourselves to wiping small files.
-#define MAX_WIPE_LENGTH 4096
-#define INIT_BUFFER_SIZE 2048
+#include <AutoCloseFD.h>
-static void usage(char *progname);
-static void destroy_key(const std::string &path);
-static int file_device_range(const std::string &path, uint64_t range[2]);
-static int open_block_device_for_path(const std::string &path);
-static int read_file_as_string_atomically(const std::string &path, std::string &contents);
-static int find_block_device_for_path(
- const std::string &mounts,
- const std::string &path,
- std::string &block_device);
+namespace {
-int main(int argc, char **argv) {
- if (argc != 2 || argv[1][0] != '/') {
+struct Options {
+ std::vector<std::string> targets;
+ bool unlink{true};
+};
+
+constexpr uint32_t max_extents = 32;
+
+bool read_command_line(int argc, const char * const argv[], Options &options);
+void usage(const char *progname);
+int secdiscard_path(const std::string &path);
+std::unique_ptr<struct fiemap> path_fiemap(const std::string &path, uint32_t extent_count);
+bool check_fiemap(const struct fiemap &fiemap, const std::string &path);
+std::unique_ptr<struct fiemap> alloc_fiemap(uint32_t extent_count);
+std::string block_device_for_path(const std::string &path);
+
+}
+
+int main(int argc, const char * const argv[]) {
+ android::base::InitLogging(const_cast<char **>(argv));
+ Options options;
+ if (!read_command_line(argc, argv, options)) {
usage(argv[0]);
return -1;
}
- SLOGD("Running: %s %s", argv[0], argv[1]);
- std::string target(argv[1]);
- destroy_key(target);
- if (unlink(argv[1]) != 0 && errno != ENOENT) {
- SLOGE("Unable to delete %s: %s",
- argv[1], strerror(errno));
- return -1;
+ for (auto target: options.targets) {
+ LOG(DEBUG) << "Securely discarding '" << target << "' unlink=" << options.unlink;
+ secdiscard_path(target);
+ if (options.unlink) {
+ if (unlink(target.c_str()) != 0 && errno != ENOENT) {
+ PLOG(ERROR) << "Unable to unlink: " << target;
+ }
+ }
+ LOG(DEBUG) << "Discarded: " << target;
}
return 0;
}
-static void usage(char *progname) {
- fprintf(stderr, "Usage: %s <absolute path>\n", progname);
+namespace {
+
+bool read_command_line(int argc, const char * const argv[], Options &options) {
+ for (int i = 1; i < argc; i++) {
+ if (!strcmp("--no-unlink", argv[i])) {
+ options.unlink = false;
+ } else if (!strcmp("--", argv[i])) {
+ for (int j = i+1; j < argc; j++) {
+ if (argv[j][0] != '/') return false; // Must be absolute path
+ options.targets.emplace_back(argv[j]);
+ }
+ return options.targets.size() > 0;
+ } else {
+ return false; // Unknown option
+ }
+ }
+ return false; // "--" not found
+}
+
+void usage(const char *progname) {
+ fprintf(stderr, "Usage: %s [--no-unlink] -- <absolute path> ...\n", progname);
}
// BLKSECDISCARD all content in "path", if it's small enough.
-static void destroy_key(const std::string &path) {
- uint64_t range[2];
- if (file_device_range(path, range) < 0) {
- return;
+int secdiscard_path(const std::string &path) {
+ auto fiemap = path_fiemap(path, max_extents);
+ if (!fiemap || !check_fiemap(*fiemap, path)) {
+ return -1;
}
- int fs_fd = open_block_device_for_path(path);
- if (fs_fd < 0) {
- return;
+ auto block_device = block_device_for_path(path);
+ if (block_device.empty()) {
+ return -1;
}
- if (ioctl(fs_fd, BLKSECDISCARD, range) != 0) {
- SLOGE("Unable to BLKSECDISCARD %s: %s", path.c_str(), strerror(errno));
- close(fs_fd);
- return;
+ AutoCloseFD fs_fd(block_device, O_RDWR | O_LARGEFILE);
+ if (!fs_fd) {
+ PLOG(ERROR) << "Failed to open device " << block_device;
+ return -1;
}
- close(fs_fd);
- SLOGD("Discarded %s", path.c_str());
-}
-
-// Find a short range that completely covers the file.
-// If there isn't one, return -1, otherwise 0.
-static int file_device_range(const std::string &path, uint64_t range[2])
-{
- int fd = open(path.c_str(), O_RDONLY | O_CLOEXEC);
- if (fd < 0) {
- if (errno == ENOENT) {
- SLOGD("Unable to open %s: %s", path.c_str(), strerror(errno));
- } else {
- SLOGE("Unable to open %s: %s", path.c_str(), strerror(errno));
+ for (uint32_t i = 0; i < fiemap->fm_mapped_extents; i++) {
+ uint64_t range[2];
+ range[0] = fiemap->fm_extents[i].fe_physical;
+ range[1] = fiemap->fm_extents[i].fe_length;
+ if (ioctl(fs_fd.get(), BLKSECDISCARD, range) == -1) {
+ PLOG(ERROR) << "Unable to BLKSECDISCARD " << path;
+ return -1;
}
- return -1;
}
- alignas(struct fiemap) char fiemap_buffer[offsetof(struct fiemap, fm_extents[1])];
- memset(fiemap_buffer, 0, sizeof(fiemap_buffer));
- struct fiemap *fiemap = (struct fiemap *)fiemap_buffer;
- fiemap->fm_start = 0;
- fiemap->fm_length = UINT64_MAX;
- fiemap->fm_flags = 0;
- fiemap->fm_extent_count = 1;
- fiemap->fm_mapped_extents = 0;
- if (ioctl(fd, FS_IOC_FIEMAP, fiemap) != 0) {
- SLOGE("Unable to FIEMAP %s: %s", path.c_str(), strerror(errno));
- close(fd);
- return -1;
- }
- close(fd);
- if (fiemap->fm_mapped_extents != 1) {
- SLOGE("Expecting one extent, got %d in %s", fiemap->fm_mapped_extents, path.c_str());
- return -1;
- }
- struct fiemap_extent *extent = &fiemap->fm_extents[0];
- if (!(extent->fe_flags & FIEMAP_EXTENT_LAST)) {
- SLOGE("First extent was not the last in %s", path.c_str());
- return -1;
- }
- if (extent->fe_flags &
- (FIEMAP_EXTENT_UNKNOWN | FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_NOT_ALIGNED)) {
- SLOGE("Extent has unexpected flags %ulx: %s", extent->fe_flags, path.c_str());
- return -1;
- }
- if (extent->fe_length > MAX_WIPE_LENGTH) {
- SLOGE("Extent too big, %llu bytes in %s", extent->fe_length, path.c_str());
- return -1;
- }
- range[0] = extent->fe_physical;
- range[1] = extent->fe_length;
return 0;
}
-// Given a file path, look for the corresponding
-// block device in /proc/mounts and open it.
-static int open_block_device_for_path(const std::string &path)
+// Read the file's FIEMAP
+std::unique_ptr<struct fiemap> path_fiemap(const std::string &path, uint32_t extent_count)
{
- std::string mountsfile("/proc/mounts");
- std::string mounts;
- if (read_file_as_string_atomically(mountsfile, mounts) < 0) {
- return -1;
+ AutoCloseFD fd(path);
+ if (!fd) {
+ if (errno == ENOENT) {
+ PLOG(DEBUG) << "Unable to open " << path;
+ } else {
+ PLOG(ERROR) << "Unable to open " << path;
+ }
+ return nullptr;
}
- std::string block_device;
- if (find_block_device_for_path(mounts, path, block_device) < 0) {
- return -1;
+ auto fiemap = alloc_fiemap(extent_count);
+ if (ioctl(fd.get(), FS_IOC_FIEMAP, fiemap.get()) != 0) {
+ PLOG(ERROR) << "Unable to FIEMAP " << path;
+ return nullptr;
}
- SLOGD("For path %s block device is %s", path.c_str(), block_device.c_str());
- int res = open(block_device.c_str(), O_RDWR | O_LARGEFILE | O_CLOEXEC);
- if (res < 0) {
- SLOGE("Failed to open device %s: %s", block_device.c_str(), strerror(errno));
- return -1;
+ auto mapped = fiemap->fm_mapped_extents;
+ if (mapped < 1 || mapped > extent_count) {
+ LOG(ERROR) << "Extent count not in bounds 1 <= " << mapped << " <= " << extent_count
+ << " in " << path;
+ return nullptr;
}
+ return fiemap;
+}
+
+// Ensure that the FIEMAP covers the file and is OK to discard
+bool check_fiemap(const struct fiemap &fiemap, const std::string &path) {
+ auto mapped = fiemap.fm_mapped_extents;
+ if (!(fiemap.fm_extents[mapped - 1].fe_flags & FIEMAP_EXTENT_LAST)) {
+ LOG(ERROR) << "Extent " << mapped -1 << " was not the last in " << path;
+ return false;
+ }
+ for (uint32_t i = 0; i < mapped; i++) {
+ auto flags = fiemap.fm_extents[i].fe_flags;
+ if (flags & (FIEMAP_EXTENT_UNKNOWN | FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_NOT_ALIGNED)) {
+ LOG(ERROR) << "Extent " << i << " has unexpected flags " << flags << ": " << path;
+ return false;
+ }
+ }
+ return true;
+}
+
+std::unique_ptr<struct fiemap> alloc_fiemap(uint32_t extent_count)
+{
+ size_t allocsize = offsetof(struct fiemap, fm_extents[extent_count]);
+ std::unique_ptr<struct fiemap> res(new (::operator new (allocsize)) struct fiemap);
+ memset(res.get(), 0, allocsize);
+ res->fm_start = 0;
+ res->fm_length = UINT64_MAX;
+ res->fm_flags = 0;
+ res->fm_extent_count = extent_count;
+ res->fm_mapped_extents = 0;
return res;
}
-// Read a file into a buffer in a single gulp, for atomicity.
-// Null-terminate the buffer.
-// Retry until the buffer is big enough.
-static int read_file_as_string_atomically(const std::string &path, std::string &contents)
+// Given a file path, look for the corresponding block device in /proc/mount
+std::string block_device_for_path(const std::string &path)
{
- ssize_t buffer_size = INIT_BUFFER_SIZE;
- while (true) {
- int fd = open(path.c_str(), O_RDONLY | O_CLOEXEC);
- if (fd < 0) {
- SLOGE("Failed to open %s: %s", path.c_str(), strerror(errno));
- return -1;
- }
- contents.resize(buffer_size);
- ssize_t read_size = read(fd, &contents[0], buffer_size);
- if (read_size < 0) {
- SLOGE("Failed to read from %s: %s", path.c_str(), strerror(errno));
- close(fd);
- return -1;
- }
- close(fd);
- if (read_size < buffer_size) {
- contents.resize(read_size);
- return 0;
- }
- SLOGD("%s too big for buffer of size %zu", path.c_str(), buffer_size);
- buffer_size <<= 1;
+ std::unique_ptr<FILE, int(*)(FILE*)> mnts(setmntent("/proc/mounts", "re"), endmntent);
+ if (!mnts) {
+ PLOG(ERROR) << "Unable to open /proc/mounts";
+ return "";
}
+ std::string result;
+ size_t best_length = 0;
+ struct mntent *mnt; // getmntent returns a thread local, so it's safe.
+ while ((mnt = getmntent(mnts.get())) != nullptr) {
+ auto l = strlen(mnt->mnt_dir);
+ if (l > best_length &&
+ path.size() > l &&
+ path[l] == '/' &&
+ path.compare(0, l, mnt->mnt_dir) == 0) {
+ result = mnt->mnt_fsname;
+ best_length = l;
+ }
+ }
+ if (result.empty()) {
+ LOG(ERROR) <<"Didn't find a mountpoint to match path " << path;
+ return "";
+ }
+ LOG(DEBUG) << "For path " << path << " block device is " << result;
+ return result;
}
-// Search a string representing the contents of /proc/mounts
-// for the mount point of a particular file by prefix matching
-// and return the corresponding block device.
-static int find_block_device_for_path(
- const std::string &mounts,
- const std::string &path,
- std::string &block_device)
-{
- auto line_begin = mounts.begin();
- size_t best_prefix = 0;
- std::string::const_iterator line_end;
- while (line_begin != mounts.end()) {
- line_end = std::find(line_begin, mounts.end(), '\n');
- if (line_end == mounts.end()) {
- break;
- }
- auto device_end = std::find(line_begin, line_end, ' ');
- if (device_end == line_end) {
- break;
- }
- auto mountpoint_begin = device_end + 1;
- auto mountpoint_end = std::find(mountpoint_begin, line_end, ' ');
- if (mountpoint_end == line_end) {
- break;
- }
- if (std::find(line_begin, mountpoint_end, '\\') != mountpoint_end) {
- // We don't correctly handle escape sequences, and we don't expect
- // to encounter any, so fail if we do.
- break;
- }
- size_t mountpoint_len = mountpoint_end - mountpoint_begin;
- if (mountpoint_len > best_prefix &&
- mountpoint_len < path.length() &&
- path[mountpoint_len] == '/' &&
- std::equal(mountpoint_begin, mountpoint_end, path.begin())) {
- block_device = std::string(line_begin, device_end);
- best_prefix = mountpoint_len;
- }
- line_begin = line_end + 1;
- }
- // All of the "break"s above are fatal parse errors.
- if (line_begin != mounts.end()) {
- auto bad_line = std::string(line_begin, line_end);
- SLOGE("Unable to parse line in %s: %s", path.c_str(), bad_line.c_str());
- return -1;
- }
- if (best_prefix == 0) {
- SLOGE("No prefix found for path: %s", path.c_str());
- return -1;
- }
- return 0;
}