1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <dirent.h>
18#include <errno.h>
19#include <fcntl.h>
20#include <fts.h>
21#include <mntent.h>
22#include <stdio.h>
23#include <stdlib.h>
24#include <string.h>
25#include <sys/ioctl.h>
26#include <sys/mount.h>
27#include <sys/stat.h>
28#include <sys/types.h>
29#include <sys/wait.h>
30#include <unistd.h>
31
32#include <linux/kdev_t.h>
33
34#define LOG_TAG "Vold"
35
36#include <openssl/md5.h>
37
38#include <android-base/logging.h>
39#include <android-base/stringprintf.h>
40#include <cutils/fs.h>
41#include <cutils/log.h>
42
43#include <selinux/android.h>
44
45#include <sysutils/NetlinkEvent.h>
46
47#include <private/android_filesystem_config.h>
48
49#include "Benchmark.h"
50#include "EmulatedVolume.h"
51#include "VolumeManager.h"
52#include "NetlinkManager.h"
53#include "ResponseCode.h"
54#include "Loop.h"
55#include "fs/Ext4.h"
56#include "fs/Vfat.h"
57#include "Utils.h"
58#include "Devmapper.h"
59#include "Process.h"
60#include "Asec.h"
61#include "VoldUtil.h"
62#include "cryptfs.h"
63
64#define MASS_STORAGE_FILE_PATH  "/sys/class/android_usb/android0/f_mass_storage/lun/file"
65
66#define ROUND_UP_POWER_OF_2(number, po2) (((!!(number & ((1U << po2) - 1))) << po2)\
67                                         + (number & (~((1U << po2) - 1))))
68
69using android::base::StringPrintf;
70
71/*
72 * Path to external storage where *only* root can access ASEC image files
73 */
74const char *VolumeManager::SEC_ASECDIR_EXT   = "/mnt/secure/asec";
75
76/*
77 * Path to internal storage where *only* root can access ASEC image files
78 */
79const char *VolumeManager::SEC_ASECDIR_INT   = "/data/app-asec";
80
81/*
82 * Path to where secure containers are mounted
83 */
84const char *VolumeManager::ASECDIR           = "/mnt/asec";
85
86/*
87 * Path to where OBBs are mounted
88 */
89const char *VolumeManager::LOOPDIR           = "/mnt/obb";
90
91static const char* kUserMountPath = "/mnt/user";
92
93static const unsigned int kMajorBlockMmc = 179;
94static const unsigned int kMajorBlockExperimentalMin = 240;
95static const unsigned int kMajorBlockExperimentalMax = 254;
96
97/* writes superblock at end of file or device given by name */
98static int writeSuperBlock(const char* name, struct asec_superblock *sb, unsigned int numImgSectors) {
99    int sbfd = open(name, O_RDWR | O_CLOEXEC);
100    if (sbfd < 0) {
101        SLOGE("Failed to open %s for superblock write (%s)", name, strerror(errno));
102        return -1;
103    }
104
105    if (lseek(sbfd, (numImgSectors * 512), SEEK_SET) < 0) {
106        SLOGE("Failed to lseek for superblock (%s)", strerror(errno));
107        close(sbfd);
108        return -1;
109    }
110
111    if (write(sbfd, sb, sizeof(struct asec_superblock)) != sizeof(struct asec_superblock)) {
112        SLOGE("Failed to write superblock (%s)", strerror(errno));
113        close(sbfd);
114        return -1;
115    }
116    close(sbfd);
117    return 0;
118}
119
120static unsigned long adjustSectorNumExt4(unsigned long numSectors) {
121    // Ext4 started to reserve 2% or 4096 clusters, whichever is smaller for
122    // preventing costly operations or unexpected ENOSPC error.
123    // Ext4::format() uses default block size without clustering.
124    unsigned long clusterSectors = 4096 / 512;
125    unsigned long reservedSectors = (numSectors * 2)/100 + (numSectors % 50 > 0);
126    numSectors += reservedSectors > (4096 * clusterSectors) ? (4096 * clusterSectors) : reservedSectors;
127    return ROUND_UP_POWER_OF_2(numSectors, 3);
128}
129
130static unsigned long adjustSectorNumFAT(unsigned long numSectors) {
131    /*
132    * Add some headroom
133    */
134    unsigned long fatSize = (((numSectors * 4) / 512) + 1) * 2;
135    numSectors += fatSize + 2;
136    /*
137    * FAT is aligned to 32 kb with 512b sectors.
138    */
139    return ROUND_UP_POWER_OF_2(numSectors, 6);
140}
141
142static int setupLoopDevice(char* buffer, size_t len, const char* asecFileName, const char* idHash, bool debug) {
143    if (Loop::lookupActive(idHash, buffer, len)) {
144        if (Loop::create(idHash, asecFileName, buffer, len)) {
145            SLOGE("ASEC loop device creation failed for %s (%s)", asecFileName, strerror(errno));
146            return -1;
147        }
148        if (debug) {
149            SLOGD("New loop device created at %s", buffer);
150        }
151    } else {
152        if (debug) {
153            SLOGD("Found active loopback for %s at %s", asecFileName, buffer);
154        }
155    }
156    return 0;
157}
158
159static int setupDevMapperDevice(char* buffer, size_t len, const char* loopDevice, const char* asecFileName, const char* key, const char* idHash , unsigned long numImgSectors, bool* createdDMDevice, bool debug) {
160    if (strcmp(key, "none")) {
161        if (Devmapper::lookupActive(idHash, buffer, len)) {
162            if (Devmapper::create(idHash, loopDevice, key, numImgSectors,
163                                  buffer, len)) {
164                SLOGE("ASEC device mapping failed for %s (%s)", asecFileName, strerror(errno));
165                return -1;
166            }
167            if (debug) {
168                SLOGD("New devmapper instance created at %s", buffer);
169            }
170        } else {
171            if (debug) {
172                SLOGD("Found active devmapper for %s at %s", asecFileName, buffer);
173            }
174        }
175        *createdDMDevice = true;
176    } else {
177        strcpy(buffer, loopDevice);
178        *createdDMDevice = false;
179    }
180    return 0;
181}
182
183static void waitForDevMapper(const char *dmDevice) {
184    /*
185     * Wait for the device mapper node to be created. Sometimes it takes a
186     * while. Wait for up to 1 second. We could also inspect incoming uevents,
187     * but that would take more effort.
188     */
189    int tries = 25;
190    while (tries--) {
191        if (!access(dmDevice, F_OK) || errno != ENOENT) {
192            break;
193        }
194        usleep(40 * 1000);
195    }
196}
197
198VolumeManager *VolumeManager::sInstance = NULL;
199
200VolumeManager *VolumeManager::Instance() {
201    if (!sInstance)
202        sInstance = new VolumeManager();
203    return sInstance;
204}
205
206VolumeManager::VolumeManager() {
207    mDebug = false;
208    mActiveContainers = new AsecIdCollection();
209    mBroadcaster = NULL;
210    mUmsSharingCount = 0;
211    mSavedDirtyRatio = -1;
212    // set dirty ratio to 0 when UMS is active
213    mUmsDirtyRatio = 0;
214}
215
216VolumeManager::~VolumeManager() {
217    delete mActiveContainers;
218}
219
220char *VolumeManager::asecHash(const char *id, char *buffer, size_t len) {
221    static const char* digits = "0123456789abcdef";
222
223    unsigned char sig[MD5_DIGEST_LENGTH];
224
225    if (buffer == NULL) {
226        SLOGE("Destination buffer is NULL");
227        errno = ESPIPE;
228        return NULL;
229    } else if (id == NULL) {
230        SLOGE("Source buffer is NULL");
231        errno = ESPIPE;
232        return NULL;
233    } else if (len < MD5_ASCII_LENGTH_PLUS_NULL) {
234        SLOGE("Target hash buffer size < %d bytes (%zu)",
235                MD5_ASCII_LENGTH_PLUS_NULL, len);
236        errno = ESPIPE;
237        return NULL;
238    }
239
240    MD5(reinterpret_cast<const unsigned char*>(id), strlen(id), sig);
241
242    char *p = buffer;
243    for (int i = 0; i < MD5_DIGEST_LENGTH; i++) {
244        *p++ = digits[sig[i] >> 4];
245        *p++ = digits[sig[i] & 0x0F];
246    }
247    *p = '\0';
248
249    return buffer;
250}
251
252int VolumeManager::setDebug(bool enable) {
253    mDebug = enable;
254    return 0;
255}
256
257int VolumeManager::start() {
258    // Always start from a clean slate by unmounting everything in
259    // directories that we own, in case we crashed.
260    unmountAll();
261
262    // Assume that we always have an emulated volume on internal
263    // storage; the framework will decide if it should be mounted.
264    CHECK(mInternalEmulated == nullptr);
265    mInternalEmulated = std::shared_ptr<android::vold::VolumeBase>(
266            new android::vold::EmulatedVolume("/data/media"));
267    mInternalEmulated->create();
268
269    return 0;
270}
271
272int VolumeManager::stop() {
273    CHECK(mInternalEmulated != nullptr);
274    mInternalEmulated->destroy();
275    mInternalEmulated = nullptr;
276    return 0;
277}
278
279void VolumeManager::handleBlockEvent(NetlinkEvent *evt) {
280    std::lock_guard<std::mutex> lock(mLock);
281
282    if (mDebug) {
283        LOG(VERBOSE) << "----------------";
284        LOG(VERBOSE) << "handleBlockEvent with action " << (int) evt->getAction();
285        evt->dump();
286    }
287
288    std::string eventPath(evt->findParam("DEVPATH")?evt->findParam("DEVPATH"):"");
289    std::string devType(evt->findParam("DEVTYPE")?evt->findParam("DEVTYPE"):"");
290
291    if (devType != "disk") return;
292
293    int major = atoi(evt->findParam("MAJOR"));
294    int minor = atoi(evt->findParam("MINOR"));
295    dev_t device = makedev(major, minor);
296
297    switch (evt->getAction()) {
298    case NetlinkEvent::Action::kAdd: {
299        for (auto source : mDiskSources) {
300            if (source->matches(eventPath)) {
301                // For now, assume that MMC and virtio-blk (the latter is
302                // emulator-specific; see Disk.cpp for details) devices are SD,
303                // and that everything else is USB
304                int flags = source->getFlags();
305                if (major == kMajorBlockMmc
306                    || (android::vold::IsRunningInEmulator()
307                    && major >= (int) kMajorBlockExperimentalMin
308                    && major <= (int) kMajorBlockExperimentalMax)) {
309                    flags |= android::vold::Disk::Flags::kSd;
310                } else {
311                    flags |= android::vold::Disk::Flags::kUsb;
312                }
313
314                auto disk = new android::vold::Disk(eventPath, device,
315                        source->getNickname(), flags);
316                disk->create();
317                mDisks.push_back(std::shared_ptr<android::vold::Disk>(disk));
318                break;
319            }
320        }
321        break;
322    }
323    case NetlinkEvent::Action::kChange: {
324        LOG(DEBUG) << "Disk at " << major << ":" << minor << " changed";
325        for (auto disk : mDisks) {
326            if (disk->getDevice() == device) {
327                disk->readMetadata();
328                disk->readPartitions();
329            }
330        }
331        break;
332    }
333    case NetlinkEvent::Action::kRemove: {
334        auto i = mDisks.begin();
335        while (i != mDisks.end()) {
336            if ((*i)->getDevice() == device) {
337                (*i)->destroy();
338                i = mDisks.erase(i);
339            } else {
340                ++i;
341            }
342        }
343        break;
344    }
345    default: {
346        LOG(WARNING) << "Unexpected block event action " << (int) evt->getAction();
347        break;
348    }
349    }
350}
351
352void VolumeManager::addDiskSource(const std::shared_ptr<DiskSource>& diskSource) {
353    mDiskSources.push_back(diskSource);
354}
355
356std::shared_ptr<android::vold::Disk> VolumeManager::findDisk(const std::string& id) {
357    for (auto disk : mDisks) {
358        if (disk->getId() == id) {
359            return disk;
360        }
361    }
362    return nullptr;
363}
364
365std::shared_ptr<android::vold::VolumeBase> VolumeManager::findVolume(const std::string& id) {
366    if (mInternalEmulated->getId() == id) {
367        return mInternalEmulated;
368    }
369    for (auto disk : mDisks) {
370        auto vol = disk->findVolume(id);
371        if (vol != nullptr) {
372            return vol;
373        }
374    }
375    return nullptr;
376}
377
378void VolumeManager::listVolumes(android::vold::VolumeBase::Type type,
379        std::list<std::string>& list) {
380    list.clear();
381    for (auto disk : mDisks) {
382        disk->listVolumes(type, list);
383    }
384}
385
386nsecs_t VolumeManager::benchmarkPrivate(const std::string& id) {
387    std::string path;
388    if (id == "private" || id == "null") {
389        path = "/data";
390    } else {
391        auto vol = findVolume(id);
392        if (vol != nullptr && vol->getState() == android::vold::VolumeBase::State::kMounted) {
393            path = vol->getPath();
394        }
395    }
396
397    if (path.empty()) {
398        LOG(WARNING) << "Failed to find volume for " << id;
399        return -1;
400    }
401
402    return android::vold::BenchmarkPrivate(path);
403}
404
405int VolumeManager::forgetPartition(const std::string& partGuid) {
406    std::string normalizedGuid;
407    if (android::vold::NormalizeHex(partGuid, normalizedGuid)) {
408        LOG(WARNING) << "Invalid GUID " << partGuid;
409        return -1;
410    }
411
412    std::string keyPath = android::vold::BuildKeyPath(normalizedGuid);
413    if (unlink(keyPath.c_str()) != 0) {
414        LOG(ERROR) << "Failed to unlink " << keyPath;
415        return -1;
416    }
417
418    return 0;
419}
420
421int VolumeManager::linkPrimary(userid_t userId) {
422    std::string source(mPrimary->getPath());
423    if (mPrimary->getType() == android::vold::VolumeBase::Type::kEmulated) {
424        source = StringPrintf("%s/%d", source.c_str(), userId);
425        fs_prepare_dir(source.c_str(), 0755, AID_ROOT, AID_ROOT);
426    }
427
428    std::string target(StringPrintf("/mnt/user/%d/primary", userId));
429    if (TEMP_FAILURE_RETRY(unlink(target.c_str()))) {
430        if (errno != ENOENT) {
431            SLOGW("Failed to unlink %s: %s", target.c_str(), strerror(errno));
432        }
433    }
434    LOG(DEBUG) << "Linking " << source << " to " << target;
435    if (TEMP_FAILURE_RETRY(symlink(source.c_str(), target.c_str()))) {
436        SLOGW("Failed to link %s to %s: %s", source.c_str(), target.c_str(),
437                strerror(errno));
438        return -errno;
439    }
440    return 0;
441}
442
443int VolumeManager::onUserAdded(userid_t userId, int userSerialNumber) {
444    mAddedUsers[userId] = userSerialNumber;
445    return 0;
446}
447
448int VolumeManager::onUserRemoved(userid_t userId) {
449    mAddedUsers.erase(userId);
450    return 0;
451}
452
453int VolumeManager::onUserStarted(userid_t userId) {
454    // Note that sometimes the system will spin up processes from Zygote
455    // before actually starting the user, so we're okay if Zygote
456    // already created this directory.
457    std::string path(StringPrintf("%s/%d", kUserMountPath, userId));
458    fs_prepare_dir(path.c_str(), 0755, AID_ROOT, AID_ROOT);
459
460    mStartedUsers.insert(userId);
461    if (mPrimary) {
462        linkPrimary(userId);
463    }
464    return 0;
465}
466
467int VolumeManager::onUserStopped(userid_t userId) {
468    mStartedUsers.erase(userId);
469    return 0;
470}
471
472int VolumeManager::setPrimary(const std::shared_ptr<android::vold::VolumeBase>& vol) {
473    mPrimary = vol;
474    for (userid_t userId : mStartedUsers) {
475        linkPrimary(userId);
476    }
477    return 0;
478}
479
480static int unmount_tree(const char* path) {
481    size_t path_len = strlen(path);
482
483    FILE* fp = setmntent("/proc/mounts", "r");
484    if (fp == NULL) {
485        ALOGE("Error opening /proc/mounts: %s", strerror(errno));
486        return -errno;
487    }
488
489    // Some volumes can be stacked on each other, so force unmount in
490    // reverse order to give us the best chance of success.
491    std::list<std::string> toUnmount;
492    mntent* mentry;
493    while ((mentry = getmntent(fp)) != NULL) {
494        if (strncmp(mentry->mnt_dir, path, path_len) == 0) {
495            toUnmount.push_front(std::string(mentry->mnt_dir));
496        }
497    }
498    endmntent(fp);
499
500    for (auto path : toUnmount) {
501        if (umount2(path.c_str(), MNT_DETACH)) {
502            ALOGW("Failed to unmount %s: %s", path.c_str(), strerror(errno));
503        }
504    }
505    return 0;
506}
507
508int VolumeManager::remountUid(uid_t uid, const std::string& mode) {
509    LOG(DEBUG) << "Remounting " << uid << " as mode " << mode;
510
511    DIR* dir;
512    struct dirent* de;
513    char rootName[PATH_MAX];
514    char pidName[PATH_MAX];
515    int pidFd;
516    int nsFd;
517    struct stat sb;
518    pid_t child;
519
520    if (!(dir = opendir("/proc"))) {
521        PLOG(ERROR) << "Failed to opendir";
522        return -1;
523    }
524
525    // Figure out root namespace to compare against below
526    if (android::vold::SaneReadLinkAt(dirfd(dir), "1/ns/mnt", rootName, PATH_MAX) == -1) {
527        PLOG(ERROR) << "Failed to readlink";
528        closedir(dir);
529        return -1;
530    }
531
532    // Poke through all running PIDs look for apps running as UID
533    while ((de = readdir(dir))) {
534        pidFd = -1;
535        nsFd = -1;
536
537        pidFd = openat(dirfd(dir), de->d_name, O_RDONLY | O_DIRECTORY | O_CLOEXEC);
538        if (pidFd < 0) {
539            goto next;
540        }
541        if (fstat(pidFd, &sb) != 0) {
542            PLOG(WARNING) << "Failed to stat " << de->d_name;
543            goto next;
544        }
545        if (sb.st_uid != uid) {
546            goto next;
547        }
548
549        // Matches so far, but refuse to touch if in root namespace
550        LOG(DEBUG) << "Found matching PID " << de->d_name;
551        if (android::vold::SaneReadLinkAt(pidFd, "ns/mnt", pidName, PATH_MAX) == -1) {
552            PLOG(WARNING) << "Failed to read namespace for " << de->d_name;
553            goto next;
554        }
555        if (!strcmp(rootName, pidName)) {
556            LOG(WARNING) << "Skipping due to root namespace";
557            goto next;
558        }
559
560        // We purposefully leave the namespace open across the fork
561        nsFd = openat(pidFd, "ns/mnt", O_RDONLY);
562        if (nsFd < 0) {
563            PLOG(WARNING) << "Failed to open namespace for " << de->d_name;
564            goto next;
565        }
566
567        if (!(child = fork())) {
568            if (setns(nsFd, CLONE_NEWNS) != 0) {
569                PLOG(ERROR) << "Failed to setns for " << de->d_name;
570                _exit(1);
571            }
572
573            unmount_tree("/storage");
574
575            std::string storageSource;
576            if (mode == "default") {
577                storageSource = "/mnt/runtime/default";
578            } else if (mode == "read") {
579                storageSource = "/mnt/runtime/read";
580            } else if (mode == "write") {
581                storageSource = "/mnt/runtime/write";
582            } else {
583                // Sane default of no storage visible
584                _exit(0);
585            }
586            if (TEMP_FAILURE_RETRY(mount(storageSource.c_str(), "/storage",
587                    NULL, MS_BIND | MS_REC | MS_SLAVE, NULL)) == -1) {
588                PLOG(ERROR) << "Failed to mount " << storageSource << " for "
589                        << de->d_name;
590                _exit(1);
591            }
592
593            // Mount user-specific symlink helper into place
594            userid_t user_id = multiuser_get_user_id(uid);
595            std::string userSource(StringPrintf("/mnt/user/%d", user_id));
596            if (TEMP_FAILURE_RETRY(mount(userSource.c_str(), "/storage/self",
597                    NULL, MS_BIND, NULL)) == -1) {
598                PLOG(ERROR) << "Failed to mount " << userSource << " for "
599                        << de->d_name;
600                _exit(1);
601            }
602
603            _exit(0);
604        }
605
606        if (child == -1) {
607            PLOG(ERROR) << "Failed to fork";
608            goto next;
609        } else {
610            TEMP_FAILURE_RETRY(waitpid(child, nullptr, 0));
611        }
612
613next:
614        close(nsFd);
615        close(pidFd);
616    }
617    closedir(dir);
618    return 0;
619}
620
621int VolumeManager::reset() {
622    // Tear down all existing disks/volumes and start from a blank slate so
623    // newly connected framework hears all events.
624    mInternalEmulated->destroy();
625    mInternalEmulated->create();
626    for (auto disk : mDisks) {
627        disk->destroy();
628        disk->create();
629    }
630    mAddedUsers.clear();
631    mStartedUsers.clear();
632    return 0;
633}
634
635int VolumeManager::shutdown() {
636    mInternalEmulated->destroy();
637    for (auto disk : mDisks) {
638        disk->destroy();
639    }
640    mDisks.clear();
641    return 0;
642}
643
644int VolumeManager::unmountAll() {
645    std::lock_guard<std::mutex> lock(mLock);
646
647    // First, try gracefully unmounting all known devices
648    if (mInternalEmulated != nullptr) {
649        mInternalEmulated->unmount();
650    }
651    for (auto disk : mDisks) {
652        disk->unmountAll();
653    }
654
655    // Worst case we might have some stale mounts lurking around, so
656    // force unmount those just to be safe.
657    FILE* fp = setmntent("/proc/mounts", "r");
658    if (fp == NULL) {
659        SLOGE("Error opening /proc/mounts: %s", strerror(errno));
660        return -errno;
661    }
662
663    // Some volumes can be stacked on each other, so force unmount in
664    // reverse order to give us the best chance of success.
665    std::list<std::string> toUnmount;
666    mntent* mentry;
667    while ((mentry = getmntent(fp)) != NULL) {
668        if (strncmp(mentry->mnt_dir, "/mnt/", 5) == 0
669                || strncmp(mentry->mnt_dir, "/storage/", 9) == 0) {
670            toUnmount.push_front(std::string(mentry->mnt_dir));
671        }
672    }
673    endmntent(fp);
674
675    for (auto path : toUnmount) {
676        SLOGW("Tearing down stale mount %s", path.c_str());
677        android::vold::ForceUnmount(path);
678    }
679
680    return 0;
681}
682
683int VolumeManager::getObbMountPath(const char *sourceFile, char *mountPath, int mountPathLen) {
684    char idHash[33];
685    if (!asecHash(sourceFile, idHash, sizeof(idHash))) {
686        SLOGE("Hash of '%s' failed (%s)", sourceFile, strerror(errno));
687        return -1;
688    }
689
690    memset(mountPath, 0, mountPathLen);
691    int written = snprintf(mountPath, mountPathLen, "%s/%s", VolumeManager::LOOPDIR, idHash);
692    if ((written < 0) || (written >= mountPathLen)) {
693        errno = EINVAL;
694        return -1;
695    }
696
697    if (access(mountPath, F_OK)) {
698        errno = ENOENT;
699        return -1;
700    }
701
702    return 0;
703}
704
705int VolumeManager::getAsecMountPath(const char *id, char *buffer, int maxlen) {
706    char asecFileName[255];
707
708    if (!isLegalAsecId(id)) {
709        SLOGE("getAsecMountPath: Invalid asec id \"%s\"", id);
710        errno = EINVAL;
711        return -1;
712    }
713
714    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
715        SLOGE("Couldn't find ASEC %s", id);
716        return -1;
717    }
718
719    memset(buffer, 0, maxlen);
720    if (access(asecFileName, F_OK)) {
721        errno = ENOENT;
722        return -1;
723    }
724
725    int written = snprintf(buffer, maxlen, "%s/%s", VolumeManager::ASECDIR, id);
726    if ((written < 0) || (written >= maxlen)) {
727        SLOGE("getAsecMountPath failed for %s: couldn't construct path in buffer", id);
728        errno = EINVAL;
729        return -1;
730    }
731
732    return 0;
733}
734
735int VolumeManager::getAsecFilesystemPath(const char *id, char *buffer, int maxlen) {
736    char asecFileName[255];
737
738    if (!isLegalAsecId(id)) {
739        SLOGE("getAsecFilesystemPath: Invalid asec id \"%s\"", id);
740        errno = EINVAL;
741        return -1;
742    }
743
744    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
745        SLOGE("Couldn't find ASEC %s", id);
746        return -1;
747    }
748
749    memset(buffer, 0, maxlen);
750    if (access(asecFileName, F_OK)) {
751        errno = ENOENT;
752        return -1;
753    }
754
755    int written = snprintf(buffer, maxlen, "%s", asecFileName);
756    if ((written < 0) || (written >= maxlen)) {
757        errno = EINVAL;
758        return -1;
759    }
760
761    return 0;
762}
763
764int VolumeManager::createAsec(const char *id, unsigned long numSectors, const char *fstype,
765        const char *key, const int ownerUid, bool isExternal) {
766    struct asec_superblock sb;
767    memset(&sb, 0, sizeof(sb));
768
769    if (!isLegalAsecId(id)) {
770        SLOGE("createAsec: Invalid asec id \"%s\"", id);
771        errno = EINVAL;
772        return -1;
773    }
774
775    const bool wantFilesystem = strcmp(fstype, "none");
776    bool usingExt4 = false;
777    if (wantFilesystem) {
778        usingExt4 = !strcmp(fstype, "ext4");
779        if (usingExt4) {
780            sb.c_opts |= ASEC_SB_C_OPTS_EXT4;
781        } else if (strcmp(fstype, "fat")) {
782            SLOGE("Invalid filesystem type %s", fstype);
783            errno = EINVAL;
784            return -1;
785        }
786    }
787
788    sb.magic = ASEC_SB_MAGIC;
789    sb.ver = ASEC_SB_VER;
790
791    if (numSectors < ((1024*1024)/512)) {
792        SLOGE("Invalid container size specified (%lu sectors)", numSectors);
793        errno = EINVAL;
794        return -1;
795    }
796
797    char asecFileName[255];
798
799    if (!findAsec(id, asecFileName, sizeof(asecFileName))) {
800        SLOGE("ASEC file '%s' currently exists - destroy it first! (%s)",
801                asecFileName, strerror(errno));
802        errno = EADDRINUSE;
803        return -1;
804    }
805
806    const char *asecDir = isExternal ? VolumeManager::SEC_ASECDIR_EXT : VolumeManager::SEC_ASECDIR_INT;
807
808    int written = snprintf(asecFileName, sizeof(asecFileName), "%s/%s.asec", asecDir, id);
809    if ((written < 0) || (size_t(written) >= sizeof(asecFileName))) {
810        errno = EINVAL;
811        return -1;
812    }
813
814    if (!access(asecFileName, F_OK)) {
815        SLOGE("ASEC file '%s' currently exists - destroy it first! (%s)",
816                asecFileName, strerror(errno));
817        errno = EADDRINUSE;
818        return -1;
819    }
820
821    unsigned long numImgSectors;
822    if (usingExt4)
823        numImgSectors = adjustSectorNumExt4(numSectors);
824    else
825        numImgSectors = adjustSectorNumFAT(numSectors);
826
827    // Add +1 for our superblock which is at the end
828    if (Loop::createImageFile(asecFileName, numImgSectors + 1)) {
829        SLOGE("ASEC image file creation failed (%s)", strerror(errno));
830        return -1;
831    }
832
833    char idHash[33];
834    if (!asecHash(id, idHash, sizeof(idHash))) {
835        SLOGE("Hash of '%s' failed (%s)", id, strerror(errno));
836        unlink(asecFileName);
837        return -1;
838    }
839
840    char loopDevice[255];
841    if (Loop::create(idHash, asecFileName, loopDevice, sizeof(loopDevice))) {
842        SLOGE("ASEC loop device creation failed (%s)", strerror(errno));
843        unlink(asecFileName);
844        return -1;
845    }
846
847    char dmDevice[255];
848    bool cleanupDm = false;
849
850    if (strcmp(key, "none")) {
851        // XXX: This is all we support for now
852        sb.c_cipher = ASEC_SB_C_CIPHER_TWOFISH;
853        if (Devmapper::create(idHash, loopDevice, key, numImgSectors, dmDevice,
854                             sizeof(dmDevice))) {
855            SLOGE("ASEC device mapping failed (%s)", strerror(errno));
856            Loop::destroyByDevice(loopDevice);
857            unlink(asecFileName);
858            return -1;
859        }
860        cleanupDm = true;
861    } else {
862        sb.c_cipher = ASEC_SB_C_CIPHER_NONE;
863        strcpy(dmDevice, loopDevice);
864    }
865
866    /*
867     * Drop down the superblock at the end of the file
868     */
869    if (writeSuperBlock(loopDevice, &sb, numImgSectors)) {
870        if (cleanupDm) {
871            Devmapper::destroy(idHash);
872        }
873        Loop::destroyByDevice(loopDevice);
874        unlink(asecFileName);
875        return -1;
876    }
877
878    if (wantFilesystem) {
879        int formatStatus;
880        char mountPoint[255];
881
882        int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
883        if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
884            SLOGE("ASEC fs format failed: couldn't construct mountPoint");
885            if (cleanupDm) {
886                Devmapper::destroy(idHash);
887            }
888            Loop::destroyByDevice(loopDevice);
889            unlink(asecFileName);
890            return -1;
891        }
892
893        if (usingExt4) {
894            formatStatus = android::vold::ext4::Format(dmDevice, numImgSectors, mountPoint);
895        } else {
896            formatStatus = android::vold::vfat::Format(dmDevice, numImgSectors);
897        }
898
899        if (formatStatus < 0) {
900            SLOGE("ASEC fs format failed (%s)", strerror(errno));
901            if (cleanupDm) {
902                Devmapper::destroy(idHash);
903            }
904            Loop::destroyByDevice(loopDevice);
905            unlink(asecFileName);
906            return -1;
907        }
908
909        if (mkdir(mountPoint, 0000)) {
910            if (errno != EEXIST) {
911                SLOGE("Mountpoint creation failed (%s)", strerror(errno));
912                if (cleanupDm) {
913                    Devmapper::destroy(idHash);
914                }
915                Loop::destroyByDevice(loopDevice);
916                unlink(asecFileName);
917                return -1;
918            }
919        }
920
921        int mountStatus;
922        if (usingExt4) {
923            mountStatus = android::vold::ext4::Mount(dmDevice, mountPoint,
924                    false, false, false);
925        } else {
926            mountStatus = android::vold::vfat::Mount(dmDevice, mountPoint,
927                    false, false, false, ownerUid, 0, 0000, false);
928        }
929
930        if (mountStatus) {
931            SLOGE("ASEC FAT mount failed (%s)", strerror(errno));
932            if (cleanupDm) {
933                Devmapper::destroy(idHash);
934            }
935            Loop::destroyByDevice(loopDevice);
936            unlink(asecFileName);
937            return -1;
938        }
939
940        if (usingExt4) {
941            int dirfd = open(mountPoint, O_DIRECTORY | O_CLOEXEC);
942            if (dirfd >= 0) {
943                if (fchown(dirfd, ownerUid, AID_SYSTEM)
944                        || fchmod(dirfd, S_IRUSR | S_IWUSR | S_IXUSR | S_ISGID | S_IRGRP | S_IXGRP)) {
945                    SLOGI("Cannot chown/chmod new ASEC mount point %s", mountPoint);
946                }
947                close(dirfd);
948            }
949        }
950    } else {
951        SLOGI("Created raw secure container %s (no filesystem)", id);
952    }
953
954    mActiveContainers->push_back(new ContainerData(strdup(id), ASEC));
955    return 0;
956}
957
958int VolumeManager::resizeAsec(const char *id, unsigned long numSectors, const char *key) {
959    char asecFileName[255];
960    char mountPoint[255];
961    bool cleanupDm = false;
962
963    if (!isLegalAsecId(id)) {
964        SLOGE("resizeAsec: Invalid asec id \"%s\"", id);
965        errno = EINVAL;
966        return -1;
967    }
968
969    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
970        SLOGE("Couldn't find ASEC %s", id);
971        return -1;
972    }
973
974    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
975    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
976       SLOGE("ASEC resize failed for %s: couldn't construct mountpoint", id);
977       return -1;
978    }
979
980    if (isMountpointMounted(mountPoint)) {
981       SLOGE("ASEC %s mounted. Unmount before resizing", id);
982       errno = EBUSY;
983       return -1;
984    }
985
986    struct asec_superblock sb;
987    int fd;
988    unsigned long oldNumSec = 0;
989
990    if ((fd = open(asecFileName, O_RDONLY | O_CLOEXEC)) < 0) {
991        SLOGE("Failed to open ASEC file (%s)", strerror(errno));
992        return -1;
993    }
994
995    struct stat info;
996    if (fstat(fd, &info) < 0) {
997        SLOGE("Failed to get file size (%s)", strerror(errno));
998        close(fd);
999        return -1;
1000    }
1001
1002    oldNumSec = info.st_size / 512;
1003
1004    unsigned long numImgSectors;
1005    if (sb.c_opts & ASEC_SB_C_OPTS_EXT4)
1006        numImgSectors = adjustSectorNumExt4(numSectors);
1007    else
1008        numImgSectors = adjustSectorNumFAT(numSectors);
1009    /*
1010     *  add one block for the superblock
1011     */
1012    SLOGD("Resizing from %lu sectors to %lu sectors", oldNumSec, numImgSectors + 1);
1013    if (oldNumSec == numImgSectors + 1) {
1014        SLOGW("Size unchanged; ignoring resize request");
1015        return 0;
1016    } else if (oldNumSec > numImgSectors + 1) {
1017        SLOGE("Only growing is currently supported.");
1018        close(fd);
1019        return -1;
1020    }
1021
1022    /*
1023     * Try to read superblock.
1024     */
1025    memset(&sb, 0, sizeof(struct asec_superblock));
1026    if (lseek(fd, ((oldNumSec - 1) * 512), SEEK_SET) < 0) {
1027        SLOGE("lseek failed (%s)", strerror(errno));
1028        close(fd);
1029        return -1;
1030    }
1031    if (read(fd, &sb, sizeof(struct asec_superblock)) != sizeof(struct asec_superblock)) {
1032        SLOGE("superblock read failed (%s)", strerror(errno));
1033        close(fd);
1034        return -1;
1035    }
1036    close(fd);
1037
1038    if (mDebug) {
1039        SLOGD("Container sb magic/ver (%.8x/%.2x)", sb.magic, sb.ver);
1040    }
1041    if (sb.magic != ASEC_SB_MAGIC || sb.ver != ASEC_SB_VER) {
1042        SLOGE("Bad container magic/version (%.8x/%.2x)", sb.magic, sb.ver);
1043        errno = EMEDIUMTYPE;
1044        return -1;
1045    }
1046
1047    if (!(sb.c_opts & ASEC_SB_C_OPTS_EXT4)) {
1048        SLOGE("Only ext4 partitions are supported for resize");
1049        errno = EINVAL;
1050        return -1;
1051    }
1052
1053    if (Loop::resizeImageFile(asecFileName, numImgSectors + 1)) {
1054        SLOGE("Resize of ASEC image file failed. Could not resize %s", id);
1055        return -1;
1056    }
1057
1058    /*
1059     * Drop down a copy of the superblock at the end of the file
1060     */
1061    if (writeSuperBlock(asecFileName, &sb, numImgSectors))
1062        goto fail;
1063
1064    char idHash[33];
1065    if (!asecHash(id, idHash, sizeof(idHash))) {
1066        SLOGE("Hash of '%s' failed (%s)", id, strerror(errno));
1067        goto fail;
1068    }
1069
1070    char loopDevice[255];
1071    if (setupLoopDevice(loopDevice, sizeof(loopDevice), asecFileName, idHash, mDebug))
1072        goto fail;
1073
1074    char dmDevice[255];
1075
1076    if (setupDevMapperDevice(dmDevice, sizeof(dmDevice), loopDevice, asecFileName, key, idHash, numImgSectors, &cleanupDm, mDebug)) {
1077        Loop::destroyByDevice(loopDevice);
1078        goto fail;
1079    }
1080
1081    /*
1082     * Wait for the device mapper node to be created.
1083     */
1084    waitForDevMapper(dmDevice);
1085
1086    if (android::vold::ext4::Resize(dmDevice, numImgSectors)) {
1087        SLOGE("Unable to resize %s (%s)", id, strerror(errno));
1088        if (cleanupDm) {
1089            Devmapper::destroy(idHash);
1090        }
1091        Loop::destroyByDevice(loopDevice);
1092        goto fail;
1093    }
1094
1095    return 0;
1096fail:
1097    Loop::resizeImageFile(asecFileName, oldNumSec);
1098    return -1;
1099}
1100
1101int VolumeManager::finalizeAsec(const char *id) {
1102    char asecFileName[255];
1103    char loopDevice[255];
1104    char mountPoint[255];
1105
1106    if (!isLegalAsecId(id)) {
1107        SLOGE("finalizeAsec: Invalid asec id \"%s\"", id);
1108        errno = EINVAL;
1109        return -1;
1110    }
1111
1112    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
1113        SLOGE("Couldn't find ASEC %s", id);
1114        return -1;
1115    }
1116
1117    char idHash[33];
1118    if (!asecHash(id, idHash, sizeof(idHash))) {
1119        SLOGE("Hash of '%s' failed (%s)", id, strerror(errno));
1120        return -1;
1121    }
1122
1123    if (Loop::lookupActive(idHash, loopDevice, sizeof(loopDevice))) {
1124        SLOGE("Unable to finalize %s (%s)", id, strerror(errno));
1125        return -1;
1126    }
1127
1128    unsigned long nr_sec = 0;
1129    struct asec_superblock sb;
1130
1131    if (Loop::lookupInfo(loopDevice, &sb, &nr_sec)) {
1132        return -1;
1133    }
1134
1135    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
1136    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1137        SLOGE("ASEC finalize failed: couldn't construct mountPoint");
1138        return -1;
1139    }
1140
1141    int result = 0;
1142    if (sb.c_opts & ASEC_SB_C_OPTS_EXT4) {
1143        result = android::vold::ext4::Mount(loopDevice, mountPoint,
1144                true, true, true);
1145    } else {
1146        result = android::vold::vfat::Mount(loopDevice, mountPoint,
1147                true, true, true, 0, 0, 0227, false);
1148    }
1149
1150    if (result) {
1151        SLOGE("ASEC finalize mount failed (%s)", strerror(errno));
1152        return -1;
1153    }
1154
1155    if (mDebug) {
1156        SLOGD("ASEC %s finalized", id);
1157    }
1158    return 0;
1159}
1160
1161int VolumeManager::fixupAsecPermissions(const char *id, gid_t gid, const char* filename) {
1162    char asecFileName[255];
1163    char loopDevice[255];
1164    char mountPoint[255];
1165
1166    if (gid < AID_APP) {
1167        SLOGE("Group ID is not in application range");
1168        return -1;
1169    }
1170
1171    if (!isLegalAsecId(id)) {
1172        SLOGE("fixupAsecPermissions: Invalid asec id \"%s\"", id);
1173        errno = EINVAL;
1174        return -1;
1175    }
1176
1177    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
1178        SLOGE("Couldn't find ASEC %s", id);
1179        return -1;
1180    }
1181
1182    char idHash[33];
1183    if (!asecHash(id, idHash, sizeof(idHash))) {
1184        SLOGE("Hash of '%s' failed (%s)", id, strerror(errno));
1185        return -1;
1186    }
1187
1188    if (Loop::lookupActive(idHash, loopDevice, sizeof(loopDevice))) {
1189        SLOGE("Unable fix permissions during lookup on %s (%s)", id, strerror(errno));
1190        return -1;
1191    }
1192
1193    unsigned long nr_sec = 0;
1194    struct asec_superblock sb;
1195
1196    if (Loop::lookupInfo(loopDevice, &sb, &nr_sec)) {
1197        return -1;
1198    }
1199
1200    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
1201    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1202        SLOGE("Unable remount to fix permissions for %s: couldn't construct mountpoint", id);
1203        return -1;
1204    }
1205
1206    int result = 0;
1207    if ((sb.c_opts & ASEC_SB_C_OPTS_EXT4) == 0) {
1208        return 0;
1209    }
1210
1211    int ret = android::vold::ext4::Mount(loopDevice, mountPoint,
1212            false /* read-only */,
1213            true  /* remount */,
1214            false /* executable */);
1215    if (ret) {
1216        SLOGE("Unable remount to fix permissions for %s (%s)", id, strerror(errno));
1217        return -1;
1218    }
1219
1220    char *paths[] = { mountPoint, NULL };
1221
1222    FTS *fts = fts_open(paths, FTS_PHYSICAL | FTS_NOCHDIR | FTS_XDEV, NULL);
1223    if (fts) {
1224        // Traverse the entire hierarchy and chown to system UID.
1225        for (FTSENT *ftsent = fts_read(fts); ftsent != NULL; ftsent = fts_read(fts)) {
1226            // We don't care about the lost+found directory.
1227            if (!strcmp(ftsent->fts_name, "lost+found")) {
1228                continue;
1229            }
1230
1231            /*
1232             * There can only be one file marked as private right now.
1233             * This should be more robust, but it satisfies the requirements
1234             * we have for right now.
1235             */
1236            const bool privateFile = !strcmp(ftsent->fts_name, filename);
1237
1238            int fd = open(ftsent->fts_accpath, O_NOFOLLOW | O_CLOEXEC);
1239            if (fd < 0) {
1240                SLOGE("Couldn't open file %s: %s", ftsent->fts_accpath, strerror(errno));
1241                result = -1;
1242                continue;
1243            }
1244
1245            result |= fchown(fd, AID_SYSTEM, privateFile? gid : AID_SYSTEM);
1246
1247            if (ftsent->fts_info & FTS_D) {
1248                result |= fchmod(fd, 0755);
1249            } else if (ftsent->fts_info & FTS_F) {
1250                result |= fchmod(fd, privateFile ? 0640 : 0644);
1251            }
1252
1253            if (selinux_android_restorecon(ftsent->fts_path, 0) < 0) {
1254                SLOGE("restorecon failed for %s: %s\n", ftsent->fts_path, strerror(errno));
1255                result |= -1;
1256            }
1257
1258            close(fd);
1259        }
1260        fts_close(fts);
1261
1262        // Finally make the directory readable by everyone.
1263        int dirfd = open(mountPoint, O_DIRECTORY | O_CLOEXEC);
1264        if (dirfd < 0 || fchmod(dirfd, 0755)) {
1265            SLOGE("Couldn't change owner of existing directory %s: %s", mountPoint, strerror(errno));
1266            result |= -1;
1267        }
1268        close(dirfd);
1269    } else {
1270        result |= -1;
1271    }
1272
1273    result |= android::vold::ext4::Mount(loopDevice, mountPoint,
1274            true /* read-only */,
1275            true /* remount */,
1276            true /* execute */);
1277
1278    if (result) {
1279        SLOGE("ASEC fix permissions failed (%s)", strerror(errno));
1280        return -1;
1281    }
1282
1283    if (mDebug) {
1284        SLOGD("ASEC %s permissions fixed", id);
1285    }
1286    return 0;
1287}
1288
1289int VolumeManager::renameAsec(const char *id1, const char *id2) {
1290    char asecFilename1[255];
1291    char *asecFilename2;
1292    char mountPoint[255];
1293
1294    const char *dir;
1295
1296    if (!isLegalAsecId(id1)) {
1297        SLOGE("renameAsec: Invalid asec id1 \"%s\"", id1);
1298        errno = EINVAL;
1299        return -1;
1300    }
1301
1302    if (!isLegalAsecId(id2)) {
1303        SLOGE("renameAsec: Invalid asec id2 \"%s\"", id2);
1304        errno = EINVAL;
1305        return -1;
1306    }
1307
1308    if (findAsec(id1, asecFilename1, sizeof(asecFilename1), &dir)) {
1309        SLOGE("Couldn't find ASEC %s", id1);
1310        return -1;
1311    }
1312
1313    asprintf(&asecFilename2, "%s/%s.asec", dir, id2);
1314
1315    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id1);
1316    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1317        SLOGE("Rename failed: couldn't construct mountpoint");
1318        goto out_err;
1319    }
1320
1321    if (isMountpointMounted(mountPoint)) {
1322        SLOGW("Rename attempt when src mounted");
1323        errno = EBUSY;
1324        goto out_err;
1325    }
1326
1327    written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id2);
1328    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1329        SLOGE("Rename failed: couldn't construct mountpoint2");
1330        goto out_err;
1331    }
1332
1333    if (isMountpointMounted(mountPoint)) {
1334        SLOGW("Rename attempt when dst mounted");
1335        errno = EBUSY;
1336        goto out_err;
1337    }
1338
1339    if (!access(asecFilename2, F_OK)) {
1340        SLOGE("Rename attempt when dst exists");
1341        errno = EADDRINUSE;
1342        goto out_err;
1343    }
1344
1345    if (rename(asecFilename1, asecFilename2)) {
1346        SLOGE("Rename of '%s' to '%s' failed (%s)", asecFilename1, asecFilename2, strerror(errno));
1347        goto out_err;
1348    }
1349
1350    free(asecFilename2);
1351    return 0;
1352
1353out_err:
1354    free(asecFilename2);
1355    return -1;
1356}
1357
1358#define UNMOUNT_RETRIES 5
1359#define UNMOUNT_SLEEP_BETWEEN_RETRY_MS (1000 * 1000)
1360int VolumeManager::unmountAsec(const char *id, bool force) {
1361    char asecFileName[255];
1362    char mountPoint[255];
1363
1364    if (!isLegalAsecId(id)) {
1365        SLOGE("unmountAsec: Invalid asec id \"%s\"", id);
1366        errno = EINVAL;
1367        return -1;
1368    }
1369
1370    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
1371        SLOGE("Couldn't find ASEC %s", id);
1372        return -1;
1373    }
1374
1375    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
1376    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1377        SLOGE("ASEC unmount failed for %s: couldn't construct mountpoint", id);
1378        return -1;
1379    }
1380
1381    char idHash[33];
1382    if (!asecHash(id, idHash, sizeof(idHash))) {
1383        SLOGE("Hash of '%s' failed (%s)", id, strerror(errno));
1384        return -1;
1385    }
1386
1387    return unmountLoopImage(id, idHash, asecFileName, mountPoint, force);
1388}
1389
1390int VolumeManager::unmountObb(const char *fileName, bool force) {
1391    char mountPoint[255];
1392
1393    char idHash[33];
1394    if (!asecHash(fileName, idHash, sizeof(idHash))) {
1395        SLOGE("Hash of '%s' failed (%s)", fileName, strerror(errno));
1396        return -1;
1397    }
1398
1399    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::LOOPDIR, idHash);
1400    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1401        SLOGE("OBB unmount failed for %s: couldn't construct mountpoint", fileName);
1402        return -1;
1403    }
1404
1405    return unmountLoopImage(fileName, idHash, fileName, mountPoint, force);
1406}
1407
1408int VolumeManager::unmountLoopImage(const char *id, const char *idHash,
1409        const char *fileName, const char *mountPoint, bool force) {
1410    if (!isMountpointMounted(mountPoint)) {
1411        SLOGE("Unmount request for %s when not mounted", id);
1412        errno = ENOENT;
1413        return -1;
1414    }
1415
1416    int i, rc;
1417    for (i = 1; i <= UNMOUNT_RETRIES; i++) {
1418        rc = umount(mountPoint);
1419        if (!rc) {
1420            break;
1421        }
1422        if (rc && (errno == EINVAL || errno == ENOENT)) {
1423            SLOGI("Container %s unmounted OK", id);
1424            rc = 0;
1425            break;
1426        }
1427        SLOGW("%s unmount attempt %d failed (%s)",
1428              id, i, strerror(errno));
1429
1430        int signal = 0; // default is to just complain
1431
1432        if (force) {
1433            if (i > (UNMOUNT_RETRIES - 2))
1434                signal = SIGKILL;
1435            else if (i > (UNMOUNT_RETRIES - 3))
1436                signal = SIGTERM;
1437        }
1438
1439        Process::killProcessesWithOpenFiles(mountPoint, signal);
1440        usleep(UNMOUNT_SLEEP_BETWEEN_RETRY_MS);
1441    }
1442
1443    if (rc) {
1444        errno = EBUSY;
1445        SLOGE("Failed to unmount container %s (%s)", id, strerror(errno));
1446        return -1;
1447    }
1448
1449    int retries = 10;
1450
1451    while(retries--) {
1452        if (!rmdir(mountPoint)) {
1453            break;
1454        }
1455
1456        SLOGW("Failed to rmdir %s (%s)", mountPoint, strerror(errno));
1457        usleep(UNMOUNT_SLEEP_BETWEEN_RETRY_MS);
1458    }
1459
1460    if (!retries) {
1461        SLOGE("Timed out trying to rmdir %s (%s)", mountPoint, strerror(errno));
1462    }
1463
1464    for (i=1; i <= UNMOUNT_RETRIES; i++) {
1465        if (Devmapper::destroy(idHash) && errno != ENXIO) {
1466            SLOGE("Failed to destroy devmapper instance (%s)", strerror(errno));
1467            usleep(UNMOUNT_SLEEP_BETWEEN_RETRY_MS);
1468            continue;
1469        } else {
1470          break;
1471        }
1472    }
1473
1474    char loopDevice[255];
1475    if (!Loop::lookupActive(idHash, loopDevice, sizeof(loopDevice))) {
1476        Loop::destroyByDevice(loopDevice);
1477    } else {
1478        SLOGW("Failed to find loop device for {%s} (%s)", fileName, strerror(errno));
1479    }
1480
1481    AsecIdCollection::iterator it;
1482    for (it = mActiveContainers->begin(); it != mActiveContainers->end(); ++it) {
1483        ContainerData* cd = *it;
1484        if (!strcmp(cd->id, id)) {
1485            free(*it);
1486            mActiveContainers->erase(it);
1487            break;
1488        }
1489    }
1490    if (it == mActiveContainers->end()) {
1491        SLOGW("mActiveContainers is inconsistent!");
1492    }
1493    return 0;
1494}
1495
1496int VolumeManager::destroyAsec(const char *id, bool force) {
1497    char asecFileName[255];
1498    char mountPoint[255];
1499
1500    if (!isLegalAsecId(id)) {
1501        SLOGE("destroyAsec: Invalid asec id \"%s\"", id);
1502        errno = EINVAL;
1503        return -1;
1504    }
1505
1506    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
1507        SLOGE("Couldn't find ASEC %s", id);
1508        return -1;
1509    }
1510
1511    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
1512    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1513        SLOGE("ASEC destroy failed for %s: couldn't construct mountpoint", id);
1514        return -1;
1515    }
1516
1517    if (isMountpointMounted(mountPoint)) {
1518        if (mDebug) {
1519            SLOGD("Unmounting container before destroy");
1520        }
1521        if (unmountAsec(id, force)) {
1522            SLOGE("Failed to unmount asec %s for destroy (%s)", id, strerror(errno));
1523            return -1;
1524        }
1525    }
1526
1527    if (unlink(asecFileName)) {
1528        SLOGE("Failed to unlink asec '%s' (%s)", asecFileName, strerror(errno));
1529        return -1;
1530    }
1531
1532    if (mDebug) {
1533        SLOGD("ASEC %s destroyed", id);
1534    }
1535    return 0;
1536}
1537
1538/*
1539 * Legal ASEC ids consist of alphanumeric characters, '-',
1540 * '_', or '.'. ".." is not allowed. The first or last character
1541 * of the ASEC id cannot be '.' (dot).
1542 */
1543bool VolumeManager::isLegalAsecId(const char *id) const {
1544    size_t i;
1545    size_t len = strlen(id);
1546
1547    if (len == 0) {
1548        return false;
1549    }
1550    if ((id[0] == '.') || (id[len - 1] == '.')) {
1551        return false;
1552    }
1553
1554    for (i = 0; i < len; i++) {
1555        if (id[i] == '.') {
1556            // i=0 is guaranteed never to have a dot. See above.
1557            if (id[i-1] == '.') return false;
1558            continue;
1559        }
1560        if (id[i] == '_' || id[i] == '-') continue;
1561        if (id[i] >= 'a' && id[i] <= 'z') continue;
1562        if (id[i] >= 'A' && id[i] <= 'Z') continue;
1563        if (id[i] >= '0' && id[i] <= '9') continue;
1564        return false;
1565    }
1566
1567    return true;
1568}
1569
1570bool VolumeManager::isAsecInDirectory(const char *dir, const char *asecName) const {
1571    int dirfd = open(dir, O_DIRECTORY | O_CLOEXEC);
1572    if (dirfd < 0) {
1573        SLOGE("Couldn't open internal ASEC dir (%s)", strerror(errno));
1574        return false;
1575    }
1576
1577    struct stat sb;
1578    bool ret = (fstatat(dirfd, asecName, &sb, AT_SYMLINK_NOFOLLOW) == 0)
1579        && S_ISREG(sb.st_mode);
1580
1581    close(dirfd);
1582
1583    return ret;
1584}
1585
1586int VolumeManager::findAsec(const char *id, char *asecPath, size_t asecPathLen,
1587        const char **directory) const {
1588    char *asecName;
1589
1590    if (!isLegalAsecId(id)) {
1591        SLOGE("findAsec: Invalid asec id \"%s\"", id);
1592        errno = EINVAL;
1593        return -1;
1594    }
1595
1596    if (asprintf(&asecName, "%s.asec", id) < 0) {
1597        SLOGE("Couldn't allocate string to write ASEC name");
1598        return -1;
1599    }
1600
1601    const char *dir;
1602    if (isAsecInDirectory(VolumeManager::SEC_ASECDIR_INT, asecName)) {
1603        dir = VolumeManager::SEC_ASECDIR_INT;
1604    } else if (isAsecInDirectory(VolumeManager::SEC_ASECDIR_EXT, asecName)) {
1605        dir = VolumeManager::SEC_ASECDIR_EXT;
1606    } else {
1607        free(asecName);
1608        return -1;
1609    }
1610
1611    if (directory != NULL) {
1612        *directory = dir;
1613    }
1614
1615    if (asecPath != NULL) {
1616        int written = snprintf(asecPath, asecPathLen, "%s/%s", dir, asecName);
1617        if ((written < 0) || (size_t(written) >= asecPathLen)) {
1618            SLOGE("findAsec failed for %s: couldn't construct ASEC path", id);
1619            free(asecName);
1620            return -1;
1621        }
1622    }
1623
1624    free(asecName);
1625    return 0;
1626}
1627
1628int VolumeManager::mountAsec(const char *id, const char *key, int ownerUid, bool readOnly) {
1629    char asecFileName[255];
1630    char mountPoint[255];
1631
1632    if (!isLegalAsecId(id)) {
1633        SLOGE("mountAsec: Invalid asec id \"%s\"", id);
1634        errno = EINVAL;
1635        return -1;
1636    }
1637
1638    if (findAsec(id, asecFileName, sizeof(asecFileName))) {
1639        SLOGE("Couldn't find ASEC %s", id);
1640        return -1;
1641    }
1642
1643    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::ASECDIR, id);
1644    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1645        SLOGE("ASEC mount failed for %s: couldn't construct mountpoint", id);
1646        return -1;
1647    }
1648
1649    if (isMountpointMounted(mountPoint)) {
1650        SLOGE("ASEC %s already mounted", id);
1651        errno = EBUSY;
1652        return -1;
1653    }
1654
1655    char idHash[33];
1656    if (!asecHash(id, idHash, sizeof(idHash))) {
1657        SLOGE("Hash of '%s' failed (%s)", id, strerror(errno));
1658        return -1;
1659    }
1660
1661    char loopDevice[255];
1662    if (setupLoopDevice(loopDevice, sizeof(loopDevice), asecFileName, idHash, mDebug))
1663        return -1;
1664
1665    char dmDevice[255];
1666    bool cleanupDm = false;
1667
1668    unsigned long nr_sec = 0;
1669    struct asec_superblock sb;
1670
1671    if (Loop::lookupInfo(loopDevice, &sb, &nr_sec)) {
1672        return -1;
1673    }
1674
1675    if (mDebug) {
1676        SLOGD("Container sb magic/ver (%.8x/%.2x)", sb.magic, sb.ver);
1677    }
1678    if (sb.magic != ASEC_SB_MAGIC || sb.ver != ASEC_SB_VER) {
1679        SLOGE("Bad container magic/version (%.8x/%.2x)", sb.magic, sb.ver);
1680        Loop::destroyByDevice(loopDevice);
1681        errno = EMEDIUMTYPE;
1682        return -1;
1683    }
1684    nr_sec--; // We don't want the devmapping to extend onto our superblock
1685
1686    if (setupDevMapperDevice(dmDevice, sizeof(dmDevice), loopDevice, asecFileName, key, idHash , nr_sec, &cleanupDm, mDebug)) {
1687        Loop::destroyByDevice(loopDevice);
1688        return -1;
1689    }
1690
1691    if (mkdir(mountPoint, 0000)) {
1692        if (errno != EEXIST) {
1693            SLOGE("Mountpoint creation failed (%s)", strerror(errno));
1694            if (cleanupDm) {
1695                Devmapper::destroy(idHash);
1696            }
1697            Loop::destroyByDevice(loopDevice);
1698            return -1;
1699        }
1700    }
1701
1702    /*
1703     * Wait for the device mapper node to be created.
1704     */
1705    waitForDevMapper(dmDevice);
1706
1707    int result;
1708    if (sb.c_opts & ASEC_SB_C_OPTS_EXT4) {
1709        result = android::vold::ext4::Mount(dmDevice, mountPoint,
1710                readOnly, false, readOnly);
1711    } else {
1712        result = android::vold::vfat::Mount(dmDevice, mountPoint,
1713                readOnly, false, readOnly, ownerUid, 0, 0222, false);
1714    }
1715
1716    if (result) {
1717        SLOGE("ASEC mount failed (%s)", strerror(errno));
1718        if (cleanupDm) {
1719            Devmapper::destroy(idHash);
1720        }
1721        Loop::destroyByDevice(loopDevice);
1722        return -1;
1723    }
1724
1725    mActiveContainers->push_back(new ContainerData(strdup(id), ASEC));
1726    if (mDebug) {
1727        SLOGD("ASEC %s mounted", id);
1728    }
1729    return 0;
1730}
1731
1732/**
1733 * Mounts an image file <code>img</code>.
1734 */
1735int VolumeManager::mountObb(const char *img, const char *key, int ownerGid) {
1736    char mountPoint[255];
1737
1738    char idHash[33];
1739    if (!asecHash(img, idHash, sizeof(idHash))) {
1740        SLOGE("Hash of '%s' failed (%s)", img, strerror(errno));
1741        return -1;
1742    }
1743
1744    int written = snprintf(mountPoint, sizeof(mountPoint), "%s/%s", VolumeManager::LOOPDIR, idHash);
1745    if ((written < 0) || (size_t(written) >= sizeof(mountPoint))) {
1746        SLOGE("OBB mount failed for %s: couldn't construct mountpoint", img);
1747        return -1;
1748    }
1749
1750    if (isMountpointMounted(mountPoint)) {
1751        SLOGE("Image %s already mounted", img);
1752        errno = EBUSY;
1753        return -1;
1754    }
1755
1756    char loopDevice[255];
1757    if (setupLoopDevice(loopDevice, sizeof(loopDevice), img, idHash, mDebug))
1758        return -1;
1759
1760    char dmDevice[255];
1761    bool cleanupDm = false;
1762    int fd;
1763    unsigned long nr_sec = 0;
1764
1765    if ((fd = open(loopDevice, O_RDWR | O_CLOEXEC)) < 0) {
1766        SLOGE("Failed to open loopdevice (%s)", strerror(errno));
1767        Loop::destroyByDevice(loopDevice);
1768        return -1;
1769    }
1770
1771    get_blkdev_size(fd, &nr_sec);
1772    if (nr_sec == 0) {
1773        SLOGE("Failed to get loop size (%s)", strerror(errno));
1774        Loop::destroyByDevice(loopDevice);
1775        close(fd);
1776        return -1;
1777    }
1778
1779    close(fd);
1780
1781    if (setupDevMapperDevice(dmDevice, sizeof(loopDevice), loopDevice, img,key, idHash, nr_sec, &cleanupDm, mDebug)) {
1782        Loop::destroyByDevice(loopDevice);
1783        return -1;
1784    }
1785
1786    if (mkdir(mountPoint, 0755)) {
1787        if (errno != EEXIST) {
1788            SLOGE("Mountpoint creation failed (%s)", strerror(errno));
1789            if (cleanupDm) {
1790                Devmapper::destroy(idHash);
1791            }
1792            Loop::destroyByDevice(loopDevice);
1793            return -1;
1794        }
1795    }
1796
1797    /*
1798     * Wait for the device mapper node to be created.
1799     */
1800    waitForDevMapper(dmDevice);
1801
1802    if (android::vold::vfat::Mount(dmDevice, mountPoint,
1803            true, false, true, 0, ownerGid, 0227, false)) {
1804        SLOGE("Image mount failed (%s)", strerror(errno));
1805        if (cleanupDm) {
1806            Devmapper::destroy(idHash);
1807        }
1808        Loop::destroyByDevice(loopDevice);
1809        return -1;
1810    }
1811
1812    mActiveContainers->push_back(new ContainerData(strdup(img), OBB));
1813    if (mDebug) {
1814        SLOGD("Image %s mounted", img);
1815    }
1816    return 0;
1817}
1818
1819int VolumeManager::listMountedObbs(SocketClient* cli) {
1820    FILE *fp = setmntent("/proc/mounts", "r");
1821    if (fp == NULL) {
1822        SLOGE("Error opening /proc/mounts (%s)", strerror(errno));
1823        return -1;
1824    }
1825
1826    // Create a string to compare against that has a trailing slash
1827    int loopDirLen = strlen(VolumeManager::LOOPDIR);
1828    char loopDir[loopDirLen + 2];
1829    strcpy(loopDir, VolumeManager::LOOPDIR);
1830    loopDir[loopDirLen++] = '/';
1831    loopDir[loopDirLen] = '\0';
1832
1833    mntent* mentry;
1834    while ((mentry = getmntent(fp)) != NULL) {
1835        if (!strncmp(mentry->mnt_dir, loopDir, loopDirLen)) {
1836            int fd = open(mentry->mnt_fsname, O_RDONLY | O_CLOEXEC);
1837            if (fd >= 0) {
1838                struct loop_info64 li;
1839                if (ioctl(fd, LOOP_GET_STATUS64, &li) >= 0) {
1840                    cli->sendMsg(ResponseCode::AsecListResult,
1841                            (const char*) li.lo_file_name, false);
1842                }
1843                close(fd);
1844            }
1845        }
1846    }
1847    endmntent(fp);
1848    return 0;
1849}
1850
1851extern "C" int vold_unmountAll(void) {
1852    VolumeManager *vm = VolumeManager::Instance();
1853    return vm->unmountAll();
1854}
1855
1856bool VolumeManager::isMountpointMounted(const char *mp)
1857{
1858    FILE *fp = setmntent("/proc/mounts", "r");
1859    if (fp == NULL) {
1860        SLOGE("Error opening /proc/mounts (%s)", strerror(errno));
1861        return false;
1862    }
1863
1864    bool found_mp = false;
1865    mntent* mentry;
1866    while ((mentry = getmntent(fp)) != NULL) {
1867        if (strcmp(mentry->mnt_dir, mp) == 0) {
1868            found_mp = true;
1869            break;
1870        }
1871    }
1872    endmntent(fp);
1873    return found_mp;
1874}
1875
1876int VolumeManager::mkdirs(char* path) {
1877    // Only offer to create directories for paths managed by vold
1878    if (strncmp(path, "/storage/", 9) == 0) {
1879        // fs_mkdirs() does symlink checking and relative path enforcement
1880        return fs_mkdirs(path, 0700);
1881    } else {
1882        SLOGE("Failed to find mounted volume for %s", path);
1883        return -EINVAL;
1884    }
1885}
1886