Checkpoint of better dynamic device support.
This is the first in a series of changes that are designed to
introduce better support for dynamic block devices.
It starts by defining a new Volume object which represents a storage
endpoint that knows how to mount, unmount, and format itself. This
could be a filesystem directly on a partition, or it could be an
emulated FUSE filesystem, an ASEC, or an OBB.
These new volumes can be "stacked" so that unmounting a volume will
also unmount any volumes stacked above it. Volumes that provide
shared storage can also be asked to present themselves (through bind
mounts) into user-specific mount areas.
This change also adds a Disk class which is created based on block
kernel netlink events. Instead of waiting for partition events from
the kernel, it uses gptfdisk to read partition details and creates
the relevant Volume objects.
Change-Id: I0e8bc1f8f9dcb24405f5e795c0658998e22ae2f7
diff --git a/Android.mk b/Android.mk
index cf2b291..cbfbbd2 100644
--- a/Android.mk
+++ b/Android.mk
@@ -17,7 +17,12 @@
CheckBattery.cpp \
VoldUtil.c \
fstrim.c \
- cryptfs.c
+ cryptfs.c \
+ Disk.cpp \
+ VolumeBase.cpp \
+ PublicVolume.cpp \
+ EmulatedVolume.cpp \
+ Utils.cpp \
common_c_includes := \
system/extras/ext4_utils \
@@ -51,7 +56,7 @@
libbatteryservice
vold_conlyflags := -std=c11
-vold_cflags := -Werror -Wall -Wno-missing-field-initializers
+vold_cflags := -Werror -Wall -Wno-missing-field-initializers -Wno-unused-variable -Wno-unused-parameter
include $(CLEAR_VARS)
diff --git a/Disk.cpp b/Disk.cpp
new file mode 100644
index 0000000..673827c
--- /dev/null
+++ b/Disk.cpp
@@ -0,0 +1,286 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "Vold"
+
+#include "Disk.h"
+#include "PublicVolume.h"
+#include "Utils.h"
+#include "VolumeBase.h"
+
+#include <cutils/log.h>
+#include <diskconfig/diskconfig.h>
+#include <utils/file.h>
+#include <utils/stringprintf.h>
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mount.h>
+
+namespace android {
+namespace vold {
+
+static const char* kSgdiskPath = "/system/bin/sgdisk";
+static const char* kSgdiskToken = " \t\n";
+
+static const char* kSysfsMmcMaxMinors = "/sys/module/mmcblk/parameters/perdev_minors";
+
+static const unsigned int kMajorBlockScsi = 8;
+static const unsigned int kMajorBlockMmc = 179;
+
+static const char* kGptBasicData = "EBD0A0A2-B9E5-4433-87C0-68B6B72699C7";
+static const char* kGptAndroidMeta = "19A710A2-B3CA-11E4-B026-10604B889DCF";
+static const char* kGptAndroidExt = "193D1EA4-B3CA-11E4-B075-10604B889DCF";
+
+enum class Table {
+ kUnknown,
+ kMbr,
+ kGpt,
+};
+
+Disk::Disk(const std::string& eventPath, dev_t device) :
+ mDevice(device), mSize(-1) {
+ mId = StringPrintf("disk:%ud:%ud", major(device), minor(device));
+ mSysPath = StringPrintf("/sys/%s", eventPath.c_str());
+ mDevPath = StringPrintf("/dev/block/vold/%ud:%ud", major(device), minor(device));
+
+ CreateDeviceNode(mDevPath, mDevice);
+}
+
+Disk::~Disk() {
+ DestroyDeviceNode(mDevPath);
+}
+
+std::shared_ptr<VolumeBase> Disk::findVolume(const std::string& id) {
+ for (std::shared_ptr<VolumeBase>& v : mParts) {
+ if (!id.compare(v->getId())) {
+ return v;
+ }
+ }
+ return nullptr;
+}
+
+status_t Disk::readMetadata() {
+ mSize = -1;
+ mLabel = "";
+
+ {
+ std::string path(mSysPath + "/size");
+ std::string tmp;
+ if (!ReadFileToString(path, &tmp)) {
+ ALOGW("Failed to read size from %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+ mSize = strtoll(tmp.c_str(), nullptr, 10);
+ }
+
+ switch (major(mDevice)) {
+ case kMajorBlockScsi: {
+ std::string path(mSysPath + "/device/vendor");
+ std::string tmp;
+ if (!ReadFileToString(path, &tmp)) {
+ ALOGW("Failed to read vendor from %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+ mLabel = tmp;
+ break;
+ }
+ case kMajorBlockMmc: {
+ std::string path(mSysPath + "/device/manfid");
+ std::string tmp;
+ if (!ReadFileToString(path, &tmp)) {
+ ALOGW("Failed to read manufacturer from %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+ uint64_t manfid = strtoll(tmp.c_str(), nullptr, 16);
+ // Our goal here is to give the user a meaningful label, ideally
+ // matching whatever is silk-screened on the card. To reduce
+ // user confusion, this list doesn't contain white-label manfid.
+ switch (manfid) {
+ case 0x000003: mLabel = "SanDisk"; break;
+ case 0x00001b: mLabel = "Samsung"; break;
+ case 0x000028: mLabel = "Lexar"; break;
+ case 0x000074: mLabel = "Transcend"; break;
+ }
+ break;
+ }
+ default: {
+ ALOGW("Unsupported block major type %d", major(mDevice));
+ return -ENOTSUP;
+ }
+ }
+
+ return OK;
+}
+
+status_t Disk::readPartitions() {
+ int8_t maxMinors = getMaxMinors();
+ if (maxMinors < 0) {
+ return -ENOTSUP;
+ }
+
+ mParts.clear();
+
+ // Parse partition table
+ std::string path(kSgdiskPath);
+ path += " --android-dump ";
+ path += mDevPath;
+ FILE* fp = popen(path.c_str(), "r");
+ if (!fp) {
+ ALOGE("Failed to run %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+
+ char line[1024];
+ Table table = Table::kUnknown;
+ while (fgets(line, sizeof(line), fp) != nullptr) {
+ char* token = strtok(line, kSgdiskToken);
+ if (!strcmp(token, "DISK")) {
+ const char* type = strtok(nullptr, kSgdiskToken);
+ ALOGD("%s: found %s partition table", mId.c_str(), type);
+ if (!strcmp(type, "mbr")) {
+ table = Table::kMbr;
+ } else if (!strcmp(type, "gpt")) {
+ table = Table::kGpt;
+ }
+ } else if (!strcmp(token, "PART")) {
+ int i = strtol(strtok(nullptr, kSgdiskToken), nullptr, 10);
+ if (i <= 0 || i > maxMinors) {
+ ALOGW("%s: ignoring partition %d beyond max supported devices",
+ mId.c_str(), i);
+ continue;
+ }
+ dev_t partDevice = makedev(major(mDevice), minor(mDevice) + i);
+
+ VolumeBase* vol = nullptr;
+ if (table == Table::kMbr) {
+ const char* type = strtok(nullptr, kSgdiskToken);
+ ALOGD("%s: MBR partition %d type %s", mId.c_str(), i, type);
+
+ switch (strtol(type, nullptr, 16)) {
+ case 0x06: // FAT16
+ case 0x0b: // W95 FAT32 (LBA)
+ case 0x0c: // W95 FAT32 (LBA)
+ case 0x0e: // W95 FAT16 (LBA)
+ vol = new PublicVolume(partDevice);
+ break;
+ }
+ } else if (table == Table::kGpt) {
+ const char* typeGuid = strtok(nullptr, kSgdiskToken);
+ const char* partGuid = strtok(nullptr, kSgdiskToken);
+ ALOGD("%s: GPT partition %d type %s, GUID %s", mId.c_str(), i,
+ typeGuid, partGuid);
+
+ if (!strcasecmp(typeGuid, kGptBasicData)) {
+ vol = new PublicVolume(partDevice);
+ } else if (!strcasecmp(typeGuid, kGptAndroidExt)) {
+ //vol = new PrivateVolume();
+ }
+ }
+
+ if (vol != nullptr) {
+ mParts.push_back(std::shared_ptr<VolumeBase>(vol));
+ }
+ }
+ }
+
+ // Ugly last ditch effort, treat entire disk as partition
+ if (table == Table::kUnknown) {
+ ALOGD("%s: unknown partition table; trying entire device", mId.c_str());
+ VolumeBase* vol = new PublicVolume(mDevice);
+ mParts.push_back(std::shared_ptr<VolumeBase>(vol));
+ }
+
+ pclose(fp);
+ return OK;
+}
+
+status_t Disk::partitionPublic() {
+ // TODO: improve this code
+
+ struct disk_info dinfo;
+ memset(&dinfo, 0, sizeof(dinfo));
+
+ if (!(dinfo.part_lst = (struct part_info *) malloc(
+ MAX_NUM_PARTS * sizeof(struct part_info)))) {
+ SLOGE("Failed to malloc prt_lst");
+ return -1;
+ }
+
+ memset(dinfo.part_lst, 0, MAX_NUM_PARTS * sizeof(struct part_info));
+ dinfo.device = strdup(mDevPath.c_str());
+ dinfo.scheme = PART_SCHEME_MBR;
+ dinfo.sect_size = 512;
+ dinfo.skip_lba = 2048;
+ dinfo.num_lba = 0;
+ dinfo.num_parts = 1;
+
+ struct part_info *pinfo = &dinfo.part_lst[0];
+
+ pinfo->name = strdup("android_sdcard");
+ pinfo->flags |= PART_ACTIVE_FLAG;
+ pinfo->type = PC_PART_TYPE_FAT32;
+ pinfo->len_kb = -1;
+
+ int rc = apply_disk_config(&dinfo, 0);
+ if (rc) {
+ SLOGE("Failed to apply disk configuration (%d)", rc);
+ goto out;
+ }
+
+out:
+ free(pinfo->name);
+ free(dinfo.device);
+ free(dinfo.part_lst);
+
+ return rc;
+}
+
+status_t Disk::partitionPrivate() {
+ return -ENOTSUP;
+}
+
+status_t Disk::partitionMixed(int8_t ratio) {
+ return -ENOTSUP;
+}
+
+int Disk::getMaxMinors() {
+ // Figure out maximum partition devices supported
+ switch (major(mDevice)) {
+ case kMajorBlockScsi: {
+ // Per Documentation/devices.txt this is static
+ return 15;
+ }
+ case kMajorBlockMmc: {
+ // Per Documentation/devices.txt this is dynamic
+ std::string tmp;
+ if (!ReadFileToString(kSysfsMmcMaxMinors, &tmp)) {
+ ALOGW("Failed to read max minors");
+ return -errno;
+ }
+ return atoi(tmp.c_str());
+ }
+ }
+
+ ALOGW("Unsupported block major type %d", major(mDevice));
+ return -ENOTSUP;
+}
+
+} // namespace vold
+} // namespace android
diff --git a/Disk.h b/Disk.h
new file mode 100644
index 0000000..eab8976
--- /dev/null
+++ b/Disk.h
@@ -0,0 +1,92 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_VOLD_DISK_H
+#define ANDROID_VOLD_DISK_H
+
+#include "Utils.h"
+
+#include <utils/Errors.h>
+
+#include <vector>
+
+namespace android {
+namespace vold {
+
+class VolumeBase;
+
+// events:
+// disk_created 127:4
+// disk_meta 127:4 [size] [label]
+// disk_destroyed 127:4
+
+// commands:
+// disk partition_public 127:4
+// disk partition_private 127:4
+// disk partition_mixed 127:4 50
+
+/*
+ * Representation of detected physical media.
+ *
+ * Knows how to create volumes based on the partition tables found, and also
+ * how to repartition itself.
+ */
+class Disk {
+public:
+ Disk(const std::string& eventPath, dev_t device);
+ virtual ~Disk();
+
+ const std::string& getId() { return mId; }
+ const std::string& getSysPath() { return mSysPath; }
+ const std::string& getDevPath() { return mDevPath; }
+ dev_t getDevice() { return mDevice; }
+ uint64_t getSize() { return mSize; }
+ const std::string& getLabel() { return mLabel; }
+
+ std::shared_ptr<VolumeBase> findVolume(const std::string& id);
+
+ status_t readMetadata();
+ status_t readPartitions();
+
+ status_t partitionPublic();
+ status_t partitionPrivate();
+ status_t partitionMixed(int8_t ratio);
+
+private:
+ /* ID that uniquely references this disk */
+ std::string mId;
+ /* Device path under sysfs */
+ std::string mSysPath;
+ /* Device path under dev */
+ std::string mDevPath;
+ /* Kernel device representing disk */
+ dev_t mDevice;
+ /* Size of disk, in bytes */
+ uint64_t mSize;
+ /* User-visible label, such as manufacturer */
+ std::string mLabel;
+ /* Current partitions on disk */
+ std::vector<std::shared_ptr<VolumeBase>> mParts;
+
+ int getMaxMinors();
+
+ DISALLOW_COPY_AND_ASSIGN(Disk);
+};
+
+} // namespace vold
+} // namespace android
+
+#endif
diff --git a/EmulatedVolume.cpp b/EmulatedVolume.cpp
new file mode 100644
index 0000000..5149962
--- /dev/null
+++ b/EmulatedVolume.cpp
@@ -0,0 +1,131 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "Vold"
+
+#include "EmulatedVolume.h"
+#include "Utils.h"
+
+#include <cutils/fs.h>
+#include <cutils/log.h>
+#include <utils/file.h>
+#include <utils/stringprintf.h>
+#include <private/android_filesystem_config.h>
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+namespace android {
+namespace vold {
+
+static const char* kFusePath = "/system/bin/sdcard";
+
+static const char* kUserMountPath = "/mnt/user";
+
+EmulatedVolume::EmulatedVolume(const std::string& rawPath, const std::string& nickname) :
+ VolumeBase(VolumeType::kEmulated), mFusePid(0), mPrimary(false) {
+ mRawPath = rawPath;
+ mFusePath = StringPrintf("/mnt/media_rw/emulated_fuse_%s", nickname.c_str());
+}
+
+EmulatedVolume::~EmulatedVolume() {
+}
+
+status_t EmulatedVolume::doMount() {
+ if (fs_prepare_dir(mFusePath.c_str(), 0770, AID_MEDIA_RW, AID_MEDIA_RW)) {
+ SLOGE("Failed to create mount point %s: %s", mFusePath.c_str(), strerror(errno));
+ return -errno;
+ }
+
+ if (!(mFusePid = fork())) {
+ if (execl(kFusePath,
+ "-u", "1023", // AID_MEDIA_RW
+ "-g", "1023", // AID_MEDIA_RW
+ "-d",
+ mRawPath.c_str(),
+ mFusePath.c_str())) {
+ SLOGE("Failed to exec: %s", strerror(errno));
+ }
+ _exit(1);
+ }
+
+ if (mFusePid == -1) {
+ SLOGE("Failed to fork: %s", strerror(errno));
+ return -errno;
+ }
+
+ return OK;
+}
+
+status_t EmulatedVolume::doUnmount() {
+ if (mFusePid > 0) {
+ kill(mFusePid, SIGTERM);
+ TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, 0));
+ mFusePid = 0;
+ }
+
+ ForceUnmount(mFusePath);
+
+ TEMP_FAILURE_RETRY(unlink(mFusePath.c_str()));
+
+ return OK;
+}
+
+status_t EmulatedVolume::doFormat() {
+ return -ENOTSUP;
+}
+
+status_t EmulatedVolume::bindUser(userid_t user) {
+ return bindUserInternal(user, true);
+}
+
+status_t EmulatedVolume::unbindUser(userid_t user) {
+ return bindUserInternal(user, false);
+}
+
+status_t EmulatedVolume::bindUserInternal(userid_t user, bool bind) {
+ if (!mPrimary) {
+ // Emulated volumes are only bound when primary
+ return OK;
+ }
+
+ std::string fromPath(StringPrintf("%s/%ud", mFusePath.c_str(), user));
+ std::string toPath(StringPrintf("%s/%ud/primary", kUserMountPath, user));
+
+ if (bind) {
+ mountBind(fromPath, toPath);
+ } else {
+ unmountBind(toPath);
+ }
+
+ return OK;
+}
+
+void EmulatedVolume::setPrimary(bool primary) {
+ if (getState() != VolumeState::kUnmounted) {
+ SLOGE("Primary state change requires %s to be unmounted", getId().c_str());
+ return;
+ }
+
+ mPrimary = primary;
+}
+
+} // namespace vold
+} // namespace android
diff --git a/EmulatedVolume.h b/EmulatedVolume.h
new file mode 100644
index 0000000..972351c
--- /dev/null
+++ b/EmulatedVolume.h
@@ -0,0 +1,72 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_VOLD_EMULATED_VOLUME_H
+#define ANDROID_VOLD_EMULATED_VOLUME_H
+
+#include "VolumeBase.h"
+
+#include <cutils/multiuser.h>
+
+namespace android {
+namespace vold {
+
+/*
+ * Shared storage emulated on top of private storage.
+ *
+ * Knows how to spawn a FUSE daemon to synthesize permissions. ObbVolume
+ * can be stacked above it.
+ *
+ * This volume is always multi-user aware, but is only binds itself to
+ * users when its primary storage. This volume should never be presented
+ * as secondary storage, since we're strongly encouraging developers to
+ * store data local to their app.
+ */
+class EmulatedVolume : public VolumeBase {
+public:
+ EmulatedVolume(const std::string& rawPath, const std::string& nickname);
+ virtual ~EmulatedVolume();
+
+ void setPrimary(bool primary);
+ bool getPrimary() { return mPrimary; }
+
+ status_t bindUser(userid_t user);
+ status_t unbindUser(userid_t user);
+
+private:
+ /* Mount point of raw storage */
+ std::string mRawPath;
+ /* Mount point of FUSE wrapper */
+ std::string mFusePath;
+ /* PID of FUSE wrapper */
+ pid_t mFusePid;
+ /* Flag indicating this is primary storage */
+ bool mPrimary;
+
+protected:
+ status_t doMount();
+ status_t doUnmount();
+ status_t doFormat();
+
+ status_t bindUserInternal(userid_t user, bool bind);
+
+ DISALLOW_COPY_AND_ASSIGN(EmulatedVolume);
+};
+
+} // namespace vold
+} // namespace android
+
+#endif
diff --git a/PublicVolume.cpp b/PublicVolume.cpp
new file mode 100644
index 0000000..78c8fa5
--- /dev/null
+++ b/PublicVolume.cpp
@@ -0,0 +1,251 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "Vold"
+
+#include "Fat.h"
+#include "PublicVolume.h"
+#include "Utils.h"
+
+#include <cutils/fs.h>
+#include <cutils/log.h>
+#include <utils/file.h>
+#include <utils/stringprintf.h>
+#include <private/android_filesystem_config.h>
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+namespace android {
+namespace vold {
+
+static const char* kBlkidPath = "/system/bin/blkid";
+static const char* kFusePath = "/system/bin/sdcard";
+
+static const char* kUserMountPath = "/mnt/user";
+
+PublicVolume::PublicVolume(dev_t device) :
+ VolumeBase(VolumeType::kPublic), mDevice(device), mFusePid(0), mPrimary(false) {
+ mId = StringPrintf("public:%ud:%ud", major(device), minor(device));
+ mDevPath = StringPrintf("/dev/block/vold/%ud:%ud", major(device), minor(device));
+ mRawPath = StringPrintf("/mnt/media_rw/public_raw_%ud:%ud", major(device), minor(device));
+ mFusePath = StringPrintf("/mnt/media_rw/public_fuse_%ud:%ud", major(device), minor(device));
+
+ CreateDeviceNode(mDevPath, device);
+}
+
+PublicVolume::~PublicVolume() {
+ DestroyDeviceNode(mDevPath);
+}
+
+status_t PublicVolume::readMetadata() {
+ mFsUuid = "";
+ mFsLabel = "";
+
+ std::string path(StringPrintf("%s -c /dev/null %s", kBlkidPath, mDevPath.c_str()));
+ FILE* fp = popen(path.c_str(), "r");
+ if (!fp) {
+ ALOGE("Failed to run %s: %s", path.c_str(), strerror(errno));
+ return -errno;
+ }
+
+ char line[1024];
+ char value[128];
+ if (fgets(line, sizeof(line), fp) != nullptr) {
+ ALOGD("blkid identified as %s", line);
+
+ char* start = strstr(line, "UUID=");
+ if (start != nullptr && sscanf(start + 5, "\"%127[^\"]\"", value) == 1) {
+ mFsUuid = value;
+ }
+
+ start = strstr(line, "LABEL=");
+ if (start != nullptr && sscanf(start + 6, "\"%127[^\"]\"", value) == 1) {
+ mFsLabel = value;
+ }
+ } else {
+ ALOGW("blkid failed to identify %s", mDevPath.c_str());
+ return -ENODATA;
+ }
+
+ pclose(fp);
+
+ // TODO: broadcast ident to framework
+ return OK;
+}
+
+status_t PublicVolume::initAsecStage() {
+ std::string legacyPath(mRawPath + "/android_secure");
+ std::string securePath(mRawPath + "/.android_secure");
+
+ // Recover legacy secure path
+ if (!access(legacyPath.c_str(), R_OK | X_OK)
+ && access(securePath.c_str(), R_OK | X_OK)) {
+ if (rename(legacyPath.c_str(), securePath.c_str())) {
+ SLOGE("Failed to rename legacy ASEC dir: %s", strerror(errno));
+ }
+ }
+
+ if (fs_prepare_dir(securePath.c_str(), 0770, AID_MEDIA_RW, AID_MEDIA_RW) != 0) {
+ SLOGW("fs_prepare_dir failed: %s", strerror(errno));
+ return -errno;
+ }
+
+ return OK;
+}
+
+status_t PublicVolume::doMount() {
+ if (Fat::check(mDevPath.c_str())) {
+ SLOGE("Failed filesystem check; not mounting");
+ return -EIO;
+ }
+
+ if (fs_prepare_dir(mRawPath.c_str(), 0770, AID_MEDIA_RW, AID_MEDIA_RW)) {
+ SLOGE("Failed to create mount point %s: %s", mRawPath.c_str(), strerror(errno));
+ return -errno;
+ }
+ if (fs_prepare_dir(mFusePath.c_str(), 0770, AID_MEDIA_RW, AID_MEDIA_RW)) {
+ SLOGE("Failed to create mount point %s: %s", mFusePath.c_str(), strerror(errno));
+ return -errno;
+ }
+
+ if (Fat::doMount(mDevPath.c_str(), mRawPath.c_str(), false, false, false,
+ AID_MEDIA_RW, AID_MEDIA_RW, 0007, true)) {
+ SLOGE("Failed to mount %s: %s", mDevPath.c_str(), strerror(errno));
+ return -EIO;
+ }
+
+ if (!(mFusePid = fork())) {
+ if (mPrimary) {
+ if (execl(kFusePath,
+ "-u", "1023", // AID_MEDIA_RW
+ "-g", "1023", // AID_MEDIA_RW
+ "-d",
+ mRawPath.c_str(),
+ mFusePath.c_str())) {
+ SLOGE("Failed to exec: %s", strerror(errno));
+ }
+ } else {
+ if (execl(kFusePath,
+ "-u", "1023", // AID_MEDIA_RW
+ "-g", "1023", // AID_MEDIA_RW
+ "-w", "1023", // AID_MEDIA_RW
+ "-d",
+ mRawPath.c_str(),
+ mFusePath.c_str())) {
+ SLOGE("Failed to exec: %s", strerror(errno));
+ }
+ }
+
+ _exit(1);
+ }
+
+ if (mFusePid == -1) {
+ SLOGE("Failed to fork: %s", strerror(errno));
+ return -errno;
+ }
+
+ return OK;
+}
+
+status_t PublicVolume::doUnmount() {
+ if (mFusePid > 0) {
+ kill(mFusePid, SIGTERM);
+ TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, 0));
+ mFusePid = 0;
+ }
+
+ ForceUnmount(mFusePath);
+ ForceUnmount(mRawPath);
+
+ TEMP_FAILURE_RETRY(unlink(mRawPath.c_str()));
+ TEMP_FAILURE_RETRY(unlink(mFusePath.c_str()));
+
+ return OK;
+}
+
+status_t PublicVolume::doFormat() {
+ if (Fat::format(mDevPath.c_str(), 0, true)) {
+ SLOGE("Failed to format: %s", strerror(errno));
+ return -errno;
+ }
+ return OK;
+}
+
+status_t PublicVolume::bindUser(userid_t user) {
+ return bindUserInternal(user, true);
+}
+
+status_t PublicVolume::unbindUser(userid_t user) {
+ return bindUserInternal(user, false);
+}
+
+status_t PublicVolume::bindUserInternal(userid_t user, bool bind) {
+ if (mPrimary) {
+ if (user == 0) {
+ std::string path(StringPrintf("%s/%ud/primary", kUserMountPath, user));
+ if (bind) {
+ mountBind(mFusePath, path);
+ } else {
+ unmountBind(path);
+ }
+ } else {
+ // Public volumes are only visible to owner when primary
+ // storage, so we don't mount for secondary users.
+ }
+ } else {
+ std::string path(StringPrintf("%s/%ud/public_%ud:%ud", kUserMountPath, user,
+ major(mDevice), minor(mDevice)));
+ if (bind) {
+ mountBind(mFusePath, path);
+ } else {
+ unmountBind(path);
+ }
+
+ if (user != 0) {
+ // To prevent information leakage between users, only owner
+ // has access to the Android directory
+ path += "/Android";
+ if (bind) {
+ if (::mount("tmpfs", path.c_str(), "tmpfs", MS_NOSUID, "mode=0000")) {
+ SLOGE("Failed to protect secondary path %s: %s",
+ path.c_str(), strerror(errno));
+ return -errno;
+ }
+ } else {
+ ForceUnmount(path);
+ }
+ }
+ }
+
+ return OK;
+}
+
+void PublicVolume::setPrimary(bool primary) {
+ if (getState() != VolumeState::kUnmounted) {
+ SLOGE("Primary state change requires %s to be unmounted", getId().c_str());
+ return;
+ }
+
+ mPrimary = primary;
+}
+
+} // namespace vold
+} // namespace android
diff --git a/PublicVolume.h b/PublicVolume.h
new file mode 100644
index 0000000..3da0995
--- /dev/null
+++ b/PublicVolume.h
@@ -0,0 +1,89 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_VOLD_PUBLIC_VOLUME_H
+#define ANDROID_VOLD_PUBLIC_VOLUME_H
+
+#include "VolumeBase.h"
+
+#include <cutils/multiuser.h>
+
+namespace android {
+namespace vold {
+
+/*
+ * Shared storage provided by public (vfat) partition.
+ *
+ * Knows how to mount itself and then spawn a FUSE daemon to synthesize
+ * permissions. AsecVolume and ObbVolume can be stacked above it.
+ *
+ * This volume is not inherently multi-user aware, so it has two possible
+ * modes of operation:
+ * 1. If primary storage for the device, it only binds itself to the
+ * owner user.
+ * 2. If secondary storage, it binds itself for all users, but masks
+ * away the Android directory for secondary users.
+ */
+class PublicVolume : public VolumeBase {
+public:
+ explicit PublicVolume(dev_t device);
+ virtual ~PublicVolume();
+
+ status_t readMetadata();
+ status_t initAsecStage();
+
+ void setPrimary(bool primary);
+ bool getPrimary() { return mPrimary; }
+
+ const std::string& getFsUuid() { return mFsUuid; }
+ const std::string& getFsLabel() { return mFsLabel; }
+
+ status_t bindUser(userid_t user);
+ status_t unbindUser(userid_t user);
+
+protected:
+ status_t doMount();
+ status_t doUnmount();
+ status_t doFormat();
+
+ status_t bindUserInternal(userid_t user, bool bind);
+
+private:
+ /* Kernel device representing partition */
+ dev_t mDevice;
+ /* Block device path */
+ std::string mDevPath;
+ /* Mount point of raw partition */
+ std::string mRawPath;
+ /* Mount point of FUSE wrapper */
+ std::string mFusePath;
+ /* PID of FUSE wrapper */
+ pid_t mFusePid;
+ /* Flag indicating this is primary storage */
+ bool mPrimary;
+
+ /* Parsed UUID from filesystem */
+ std::string mFsUuid;
+ /* User-visible label from filesystem */
+ std::string mFsLabel;
+
+ DISALLOW_COPY_AND_ASSIGN(PublicVolume);
+};
+
+} // namespace vold
+} // namespace android
+
+#endif
diff --git a/Utils.cpp b/Utils.cpp
new file mode 100644
index 0000000..7cbb2ce
--- /dev/null
+++ b/Utils.cpp
@@ -0,0 +1,105 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "Vold"
+
+#include "sehandle.h"
+#include "Utils.h"
+#include "Process.h"
+
+#include <cutils/fs.h>
+#include <cutils/log.h>
+#include <utils/file.h>
+#include <utils/stringprintf.h>
+#include <private/android_filesystem_config.h>
+
+#include <fcntl.h>
+#include <linux/fs.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#ifndef UMOUNT_NOFOLLOW
+#define UMOUNT_NOFOLLOW 0x00000008 /* Don't follow symlink on umount */
+#endif
+
+namespace android {
+namespace vold {
+
+status_t CreateDeviceNode(const std::string& path, dev_t dev) {
+ const char* cpath = path.c_str();
+ status_t res = 0;
+
+ char* secontext = nullptr;
+ if (sehandle) {
+ if (!selabel_lookup(sehandle, &secontext, cpath, S_IFBLK)) {
+ setfscreatecon(secontext);
+ }
+ }
+
+ mode_t mode = 0660 | S_IFBLK;
+ if (mknod(cpath, mode, dev) < 0) {
+ if (errno != EEXIST) {
+ ALOGW("Failed to create device node for %ud:%ud at %s: %s",
+ major(dev), minor(dev), cpath, strerror(errno));
+ res = -errno;
+ }
+ }
+
+ if (secontext) {
+ setfscreatecon(nullptr);
+ freecon(secontext);
+ }
+
+ return res;
+}
+
+status_t DestroyDeviceNode(const std::string& path) {
+ const char* cpath = path.c_str();
+ if (TEMP_FAILURE_RETRY(unlink(cpath))) {
+ return -errno;
+ } else {
+ return OK;
+ }
+}
+
+status_t ForceUnmount(const std::string& path) {
+ const char* cpath = path.c_str();
+ if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+ return OK;
+ }
+ ALOGW("Failed to unmount %s (%s), sending SIGTERM", cpath, strerror(errno));
+ Process::killProcessesWithOpenFiles(cpath, SIGTERM);
+ sleep(1);
+
+ if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+ return OK;
+ }
+ ALOGW("Failed to unmount %s (%s), sending SIGKILL", cpath, strerror(errno));
+ Process::killProcessesWithOpenFiles(cpath, SIGKILL);
+ sleep(1);
+
+ if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+ return OK;
+ }
+ ALOGW("Failed to unmount %s (%s)", cpath, strerror(errno));
+ return -errno;
+}
+
+} // namespace vold
+} // namespace android
diff --git a/Utils.h b/Utils.h
new file mode 100644
index 0000000..5199af6
--- /dev/null
+++ b/Utils.h
@@ -0,0 +1,44 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_VOLD_UTILS_H
+#define ANDROID_VOLD_UTILS_H
+
+#include <utils/Errors.h>
+
+#include <string>
+
+// DISALLOW_COPY_AND_ASSIGN disallows the copy and operator= functions. It goes in the private:
+// declarations in a class.
+#if !defined(DISALLOW_COPY_AND_ASSIGN)
+#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
+ TypeName(const TypeName&) = delete; \
+ void operator=(const TypeName&) = delete
+#endif
+
+namespace android {
+namespace vold {
+
+status_t CreateDeviceNode(const std::string& path, dev_t dev);
+status_t DestroyDeviceNode(const std::string& path);
+
+/* Really unmounts the path, killing active processes along the way */
+status_t ForceUnmount(const std::string& path);
+
+} // namespace vold
+} // namespace android
+
+#endif
diff --git a/VolumeBase.cpp b/VolumeBase.cpp
new file mode 100644
index 0000000..307791d
--- /dev/null
+++ b/VolumeBase.cpp
@@ -0,0 +1,131 @@
+/*
+ * 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.
+ */
+
+#define LOG_TAG "Vold"
+
+#include "Utils.h"
+#include "VolumeBase.h"
+
+#include <cutils/log.h>
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+namespace android {
+namespace vold {
+
+VolumeBase::VolumeBase(VolumeType type) :
+ mType(type), mState(VolumeState::kUnmounted) {
+}
+
+VolumeBase::~VolumeBase() {
+}
+
+void VolumeBase::setState(VolumeState state) {
+ mState = state;
+
+ // TODO: publish state up to framework
+}
+
+void VolumeBase::stackVolume(const std::shared_ptr<VolumeBase>& volume) {
+ mStacked.push_back(volume);
+}
+
+void VolumeBase::unstackVolume(const std::shared_ptr<VolumeBase>& volume) {
+ mStacked.remove(volume);
+}
+
+status_t VolumeBase::mount() {
+ if (getState() != VolumeState::kUnmounted) {
+ SLOGE("Must be unmounted to mount %s", getId().c_str());
+ return -EBUSY;
+ }
+
+ setState(VolumeState::kMounting);
+ status_t res = doMount();
+ if (!res) {
+ setState(VolumeState::kMounted);
+ } else {
+ setState(VolumeState::kCorrupt);
+ }
+
+ return res;
+}
+
+status_t VolumeBase::unmount() {
+ if (getState() != VolumeState::kMounted) {
+ SLOGE("Must be mounted to unmount %s", getId().c_str());
+ return -EBUSY;
+ }
+
+ setState(VolumeState::kUnmounting);
+
+ for (std::string target : mBindTargets) {
+ ForceUnmount(target);
+ }
+ mBindTargets.clear();
+
+ for (std::shared_ptr<VolumeBase> v : mStacked) {
+ if (v->unmount()) {
+ ALOGW("Failed to unmount %s stacked above %s", v->getId().c_str(),
+ getId().c_str());
+ }
+ }
+ mStacked.clear();
+
+ status_t res = doUnmount();
+ setState(VolumeState::kUnmounted);
+ return res;
+}
+
+status_t VolumeBase::format() {
+ if (getState() != VolumeState::kUnmounted
+ || getState() != VolumeState::kCorrupt) {
+ SLOGE("Must be unmounted or corrupt to format %s", getId().c_str());
+ return -EBUSY;
+ }
+
+ setState(VolumeState::kFormatting);
+ status_t res = doFormat();
+ setState(VolumeState::kUnmounted);
+ return res;
+}
+
+status_t VolumeBase::doFormat() {
+ return -ENOTSUP;
+}
+
+status_t VolumeBase::mountBind(const std::string& source, const std::string& target) {
+ if (::mount(source.c_str(), target.c_str(), "", MS_BIND, NULL)) {
+ SLOGE("Failed to bind mount %s to %s: %s", source.c_str(),
+ target.c_str(), strerror(errno));
+ return -errno;
+ }
+ mBindTargets.push_back(target);
+ return OK;
+}
+
+status_t VolumeBase::unmountBind(const std::string& target) {
+ ForceUnmount(target);
+ mBindTargets.remove(target);
+ return OK;
+}
+
+} // namespace vold
+} // namespace android
diff --git a/VolumeBase.h b/VolumeBase.h
new file mode 100644
index 0000000..04240b7
--- /dev/null
+++ b/VolumeBase.h
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2008 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_VOLUME_BASE_H
+#define ANDROID_VOLD_VOLUME_BASE_H
+
+#include "Utils.h"
+
+#include <utils/Errors.h>
+
+#include <sys/types.h>
+#include <list>
+#include <string>
+
+namespace android {
+namespace vold {
+
+enum class VolumeState {
+ kUnmounted,
+ kMounting,
+ kMounted,
+ kCorrupt,
+ kFormatting,
+ kUnmounting,
+};
+
+enum class VolumeType {
+ kPublic,
+ kPrivate,
+ kEmulated,
+ kAsec,
+ kObb,
+};
+
+// events:
+// volume_created private:127:4
+// volume_state private:127:4 mounted
+// volume_meta private:127:4 [fsGuid] [label]
+// volume_destroyed public:127:4
+
+// commands:
+// volume mount public:127:4 [primary]
+// volume unmount public:127:4
+// volume bind_user public:127:4 [userId]
+// volume unbind_user public:127:4 [userId]
+// volume bind_package private:4:1 [userId] [package]
+// volume unbind_package private:4:1 [userId] [package]
+
+/*
+ * Representation of a mounted volume ready for presentation.
+ *
+ * Various subclasses handle the different mounting prerequisites, such as
+ * encryption details, etc. Volumes can also be "stacked" above other
+ * volumes to help communicate dependencies. For example, an ASEC volume
+ * can be stacked on a vfat volume.
+ *
+ * Mounted volumes can be asked to manage bind mounts to present themselves
+ * to specific users on the device.
+ *
+ * When an unmount is requested, the volume recursively unmounts any stacked
+ * volumes and removes any bind mounts before finally unmounting itself.
+ */
+class VolumeBase {
+public:
+ virtual ~VolumeBase();
+
+ VolumeType getType() { return mType; }
+ const std::string& getId() { return mId; }
+ VolumeState getState() { return mState; }
+
+ void stackVolume(const std::shared_ptr<VolumeBase>& volume);
+ void unstackVolume(const std::shared_ptr<VolumeBase>& volume);
+
+ status_t mount();
+ status_t unmount();
+ status_t format();
+
+protected:
+ explicit VolumeBase(VolumeType type);
+
+ /* ID that uniquely references this disk */
+ std::string mId;
+
+ /* Manage bind mounts for this volume */
+ status_t mountBind(const std::string& source, const std::string& target);
+ status_t unmountBind(const std::string& target);
+
+ virtual status_t doMount() = 0;
+ virtual status_t doUnmount() = 0;
+ virtual status_t doFormat();
+
+private:
+ /* Volume type */
+ VolumeType mType;
+ /* Current state of volume */
+ VolumeState mState;
+
+ /* Volumes stacked on top of this volume */
+ std::list<std::shared_ptr<VolumeBase>> mStacked;
+ /* Currently active bind mounts */
+ std::list<std::string> mBindTargets;
+
+ void setState(VolumeState state);
+
+ DISALLOW_COPY_AND_ASSIGN(VolumeBase);
+};
+
+} // namespace vold
+} // namespace android
+
+#endif