/* * Copyright (C) 2015 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "Disk.h" #include "PublicVolume.h" #include "PrivateVolume.h" #include "Utils.h" #include "VolumeBase.h" #include "VolumeManager.h" #include "ResponseCode.h" #include "Ext4Crypt.h" #include <android-base/file.h> #include <android-base/stringprintf.h> #include <android-base/logging.h> #include <diskconfig/diskconfig.h> #include <vector> #include <fcntl.h> #include <inttypes.h> #include <stdio.h> #include <stdlib.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/mount.h> using android::base::ReadFileToString; using android::base::WriteStringToFile; using android::base::StringPrintf; 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 kMajorBlockScsiA = 8; static const unsigned int kMajorBlockScsiB = 65; static const unsigned int kMajorBlockScsiC = 66; static const unsigned int kMajorBlockScsiD = 67; static const unsigned int kMajorBlockScsiE = 68; static const unsigned int kMajorBlockScsiF = 69; static const unsigned int kMajorBlockScsiG = 70; static const unsigned int kMajorBlockScsiH = 71; static const unsigned int kMajorBlockScsiI = 128; static const unsigned int kMajorBlockScsiJ = 129; static const unsigned int kMajorBlockScsiK = 130; static const unsigned int kMajorBlockScsiL = 131; static const unsigned int kMajorBlockScsiM = 132; static const unsigned int kMajorBlockScsiN = 133; static const unsigned int kMajorBlockScsiO = 134; static const unsigned int kMajorBlockScsiP = 135; static const unsigned int kMajorBlockMmc = 179; static const unsigned int kMajorBlockExperimentalMin = 240; static const unsigned int kMajorBlockExperimentalMax = 254; static const char* kGptBasicData = "EBD0A0A2-B9E5-4433-87C0-68B6B72699C7"; static const char* kGptAndroidMeta = "19A710A2-B3CA-11E4-B026-10604B889DCF"; static const char* kGptAndroidExpand = "193D1EA4-B3CA-11E4-B075-10604B889DCF"; enum class Table { kUnknown, kMbr, kGpt, }; static bool isVirtioBlkDevice(unsigned int major) { /* * The new emulator's "ranchu" virtual board no longer includes a goldfish * MMC-based SD card device; instead, it emulates SD cards with virtio-blk, * which has been supported by upstream kernel and QEMU for quite a while. * Unfortunately, the virtio-blk block device driver does not use a fixed * major number, but relies on the kernel to assign one from a specific * range of block majors, which are allocated for "LOCAL/EXPERIMENAL USE" * per Documentation/devices.txt. This is true even for the latest Linux * kernel (4.4; see init() in drivers/block/virtio_blk.c). * * This makes it difficult for vold to detect a virtio-blk based SD card. * The current solution checks two conditions (both must be met): * * a) If the running environment is the emulator; * b) If the major number is an experimental block device major number (for * x86/x86_64 3.10 ranchu kernels, virtio-blk always gets major number * 253, but it is safer to match the range than just one value). * * Other conditions could be used, too, e.g. the hardware name should be * "ranchu", the device's sysfs path should end with "/block/vd[d-z]", etc. * But just having a) and b) is enough for now. */ return IsRunningInEmulator() && major >= kMajorBlockExperimentalMin && major <= kMajorBlockExperimentalMax; } Disk::Disk(const std::string& eventPath, dev_t device, const std::string& nickname, int flags) : mDevice(device), mSize(-1), mNickname(nickname), mFlags(flags), mCreated( false), mJustPartitioned(false) { mId = StringPrintf("disk:%u,%u", major(device), minor(device)); mEventPath = eventPath; mSysPath = StringPrintf("/sys/%s", eventPath.c_str()); mDevPath = StringPrintf("/dev/block/vold/%s", mId.c_str()); CreateDeviceNode(mDevPath, mDevice); } Disk::~Disk() { CHECK(!mCreated); DestroyDeviceNode(mDevPath); } std::shared_ptr<VolumeBase> Disk::findVolume(const std::string& id) { for (auto vol : mVolumes) { if (vol->getId() == id) { return vol; } auto stackedVol = vol->findVolume(id); if (stackedVol != nullptr) { return stackedVol; } } return nullptr; } void Disk::listVolumes(VolumeBase::Type type, std::list<std::string>& list) { for (auto vol : mVolumes) { if (vol->getType() == type) { list.push_back(vol->getId()); } // TODO: consider looking at stacked volumes } } status_t Disk::create() { CHECK(!mCreated); mCreated = true; notifyEvent(ResponseCode::DiskCreated, StringPrintf("%d", mFlags)); readMetadata(); readPartitions(); return OK; } status_t Disk::destroy() { CHECK(mCreated); destroyAllVolumes(); mCreated = false; notifyEvent(ResponseCode::DiskDestroyed); return OK; } void Disk::createPublicVolume(dev_t device) { auto vol = std::shared_ptr<VolumeBase>(new PublicVolume(device)); if (mJustPartitioned) { LOG(DEBUG) << "Device just partitioned; silently formatting"; vol->setSilent(true); vol->create(); vol->format("auto"); vol->destroy(); vol->setSilent(false); } mVolumes.push_back(vol); vol->setDiskId(getId()); vol->create(); } void Disk::createPrivateVolume(dev_t device, const std::string& partGuid) { std::string normalizedGuid; if (NormalizeHex(partGuid, normalizedGuid)) { LOG(WARNING) << "Invalid GUID " << partGuid; return; } std::string keyRaw; if (!ReadFileToString(BuildKeyPath(normalizedGuid), &keyRaw)) { PLOG(ERROR) << "Failed to load key for GUID " << normalizedGuid; return; } LOG(DEBUG) << "Found key for GUID " << normalizedGuid; auto vol = std::shared_ptr<VolumeBase>(new PrivateVolume(device, keyRaw)); if (mJustPartitioned) { LOG(DEBUG) << "Device just partitioned; silently formatting"; vol->setSilent(true); vol->create(); vol->format("auto"); vol->destroy(); vol->setSilent(false); } mVolumes.push_back(vol); vol->setDiskId(getId()); vol->setPartGuid(partGuid); vol->create(); } void Disk::destroyAllVolumes() { for (auto vol : mVolumes) { vol->destroy(); } mVolumes.clear(); } status_t Disk::readMetadata() { mSize = -1; mLabel.clear(); int fd = open(mDevPath.c_str(), O_RDONLY | O_CLOEXEC); if (fd != -1) { if (ioctl(fd, BLKGETSIZE64, &mSize)) { mSize = -1; } close(fd); } unsigned int majorId = major(mDevice); switch (majorId) { case kMajorBlockScsiA: case kMajorBlockScsiB: case kMajorBlockScsiC: case kMajorBlockScsiD: case kMajorBlockScsiE: case kMajorBlockScsiF: case kMajorBlockScsiG: case kMajorBlockScsiH: case kMajorBlockScsiI: case kMajorBlockScsiJ: case kMajorBlockScsiK: case kMajorBlockScsiL: case kMajorBlockScsiM: case kMajorBlockScsiN: case kMajorBlockScsiO: case kMajorBlockScsiP: { std::string path(mSysPath + "/device/vendor"); std::string tmp; if (!ReadFileToString(path, &tmp)) { PLOG(WARNING) << "Failed to read vendor from " << path; return -errno; } mLabel = tmp; break; } case kMajorBlockMmc: { std::string path(mSysPath + "/device/manfid"); std::string tmp; if (!ReadFileToString(path, &tmp)) { PLOG(WARNING) << "Failed to read manufacturer from " << path; 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: { if (isVirtioBlkDevice(majorId)) { LOG(DEBUG) << "Recognized experimental block major ID " << majorId << " as virtio-blk (emulator's virtual SD card device)"; mLabel = "Virtual"; break; } LOG(WARNING) << "Unsupported block major type " << majorId; return -ENOTSUP; } } notifyEvent(ResponseCode::DiskSizeChanged, StringPrintf("%" PRIu64, mSize)); notifyEvent(ResponseCode::DiskLabelChanged, mLabel); notifyEvent(ResponseCode::DiskSysPathChanged, mSysPath); return OK; } status_t Disk::readPartitions() { int8_t maxMinors = getMaxMinors(); if (maxMinors < 0) { return -ENOTSUP; } destroyAllVolumes(); // Parse partition table std::vector<std::string> cmd; cmd.push_back(kSgdiskPath); cmd.push_back("--android-dump"); cmd.push_back(mDevPath); std::vector<std::string> output; status_t res = ForkExecvp(cmd, output); if (res != OK) { LOG(WARNING) << "sgdisk failed to scan " << mDevPath; notifyEvent(ResponseCode::DiskScanned); mJustPartitioned = false; return res; } Table table = Table::kUnknown; bool foundParts = false; for (auto line : output) { char* cline = (char*) line.c_str(); char* token = strtok(cline, kSgdiskToken); if (token == nullptr) continue; if (!strcmp(token, "DISK")) { const char* type = strtok(nullptr, kSgdiskToken); if (!strcmp(type, "mbr")) { table = Table::kMbr; } else if (!strcmp(type, "gpt")) { table = Table::kGpt; } } else if (!strcmp(token, "PART")) { foundParts = true; int i = strtol(strtok(nullptr, kSgdiskToken), nullptr, 10); if (i <= 0 || i > maxMinors) { LOG(WARNING) << mId << " is ignoring partition " << i << " beyond max supported devices"; continue; } dev_t partDevice = makedev(major(mDevice), minor(mDevice) + i); if (table == Table::kMbr) { const char* type = strtok(nullptr, kSgdiskToken); switch (strtol(type, nullptr, 16)) { case 0x06: // FAT16 case 0x0b: // W95 FAT32 (LBA) case 0x0c: // W95 FAT32 (LBA) case 0x0e: // W95 FAT16 (LBA) createPublicVolume(partDevice); break; } } else if (table == Table::kGpt) { const char* typeGuid = strtok(nullptr, kSgdiskToken); const char* partGuid = strtok(nullptr, kSgdiskToken); if (!strcasecmp(typeGuid, kGptBasicData)) { createPublicVolume(partDevice); } else if (!strcasecmp(typeGuid, kGptAndroidExpand)) { createPrivateVolume(partDevice, partGuid); } } } } // Ugly last ditch effort, treat entire disk as partition if (table == Table::kUnknown || !foundParts) { LOG(WARNING) << mId << " has unknown partition table; trying entire device"; std::string fsType; std::string unused; if (ReadMetadataUntrusted(mDevPath, fsType, unused, unused) == OK) { createPublicVolume(mDevice); } else { LOG(WARNING) << mId << " failed to identify, giving up"; } } notifyEvent(ResponseCode::DiskScanned); mJustPartitioned = false; return OK; } status_t Disk::unmountAll() { for (auto vol : mVolumes) { vol->unmount(); } return OK; } status_t Disk::partitionPublic() { int res; // TODO: improve this code destroyAllVolumes(); mJustPartitioned = true; // First nuke any existing partition table std::vector<std::string> cmd; cmd.push_back(kSgdiskPath); cmd.push_back("--zap-all"); cmd.push_back(mDevPath); // Zap sometimes returns an error when it actually succeeded, so // just log as warning and keep rolling forward. if ((res = ForkExecvp(cmd)) != 0) { LOG(WARNING) << "Failed to zap; status " << res; } struct disk_info dinfo; memset(&dinfo, 0, sizeof(dinfo)); if (!(dinfo.part_lst = (struct part_info *) malloc( MAX_NUM_PARTS * sizeof(struct part_info)))) { 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) { LOG(ERROR) << "Failed to apply disk configuration: " << rc; goto out; } out: free(pinfo->name); free(dinfo.device); free(dinfo.part_lst); return rc; } status_t Disk::partitionPrivate() { return partitionMixed(0); } status_t Disk::partitionMixed(int8_t ratio) { int res; if (e4crypt_is_native()) { LOG(ERROR) << "Private volumes not yet supported on FBE devices"; return -EINVAL; } destroyAllVolumes(); mJustPartitioned = true; // First nuke any existing partition table std::vector<std::string> cmd; cmd.push_back(kSgdiskPath); cmd.push_back("--zap-all"); cmd.push_back(mDevPath); // Zap sometimes returns an error when it actually succeeded, so // just log as warning and keep rolling forward. if ((res = ForkExecvp(cmd)) != 0) { LOG(WARNING) << "Failed to zap; status " << res; } // We've had some success above, so generate both the private partition // GUID and encryption key and persist them. std::string partGuidRaw; std::string keyRaw; if (ReadRandomBytes(16, partGuidRaw) || ReadRandomBytes(16, keyRaw)) { LOG(ERROR) << "Failed to generate GUID or key"; return -EIO; } std::string partGuid; StrToHex(partGuidRaw, partGuid); if (!WriteStringToFile(keyRaw, BuildKeyPath(partGuid))) { LOG(ERROR) << "Failed to persist key"; return -EIO; } else { LOG(DEBUG) << "Persisted key for GUID " << partGuid; } // Now let's build the new GPT table. We heavily rely on sgdisk to // force optimal alignment on the created partitions. cmd.clear(); cmd.push_back(kSgdiskPath); // If requested, create a public partition first. Mixed-mode partitioning // like this is an experimental feature. if (ratio > 0) { if (ratio < 10 || ratio > 90) { LOG(ERROR) << "Mixed partition ratio must be between 10-90%"; return -EINVAL; } uint64_t splitMb = ((mSize / 100) * ratio) / 1024 / 1024; cmd.push_back(StringPrintf("--new=0:0:+%" PRId64 "M", splitMb)); cmd.push_back(StringPrintf("--typecode=0:%s", kGptBasicData)); cmd.push_back("--change-name=0:shared"); } // Define a metadata partition which is designed for future use; there // should only be one of these per physical device, even if there are // multiple private volumes. cmd.push_back("--new=0:0:+16M"); cmd.push_back(StringPrintf("--typecode=0:%s", kGptAndroidMeta)); cmd.push_back("--change-name=0:android_meta"); // Define a single private partition filling the rest of disk. cmd.push_back("--new=0:0:-0"); cmd.push_back(StringPrintf("--typecode=0:%s", kGptAndroidExpand)); cmd.push_back(StringPrintf("--partition-guid=0:%s", partGuid.c_str())); cmd.push_back("--change-name=0:android_expand"); cmd.push_back(mDevPath); if ((res = ForkExecvp(cmd)) != 0) { LOG(ERROR) << "Failed to partition; status " << res; return res; } return OK; } void Disk::notifyEvent(int event) { VolumeManager::Instance()->getBroadcaster()->sendBroadcast(event, getId().c_str(), false); } void Disk::notifyEvent(int event, const std::string& value) { VolumeManager::Instance()->getBroadcaster()->sendBroadcast(event, StringPrintf("%s %s", getId().c_str(), value.c_str()).c_str(), false); } int Disk::getMaxMinors() { // Figure out maximum partition devices supported unsigned int majorId = major(mDevice); switch (majorId) { case kMajorBlockScsiA: case kMajorBlockScsiB: case kMajorBlockScsiC: case kMajorBlockScsiD: case kMajorBlockScsiE: case kMajorBlockScsiF: case kMajorBlockScsiG: case kMajorBlockScsiH: case kMajorBlockScsiI: case kMajorBlockScsiJ: case kMajorBlockScsiK: case kMajorBlockScsiL: case kMajorBlockScsiM: case kMajorBlockScsiN: case kMajorBlockScsiO: case kMajorBlockScsiP: { // 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)) { LOG(ERROR) << "Failed to read max minors"; return -errno; } return atoi(tmp.c_str()); } default: { if (isVirtioBlkDevice(majorId)) { // drivers/block/virtio_blk.c has "#define PART_BITS 4", so max is // 2^4 - 1 = 15 return 15; } } } LOG(ERROR) << "Unsupported block major type " << majorId; return -ENOTSUP; } } // namespace vold } // namespace android