upload android base code part6

android/system/vold/Utils.cpp

@@ -0,0 +1,693 @@
+/*
+ * 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 "sehandle.h"
+#include "Utils.h"
+#include "Process.h"
+#include "VolumeManager.h"
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
+#include <cutils/fs.h>
+#include <logwrap/logwrap.h>
+#include <private/android_filesystem_config.h>
+
+#include <mutex>
+#include <dirent.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/sysmacros.h>
+#include <sys/wait.h>
+#include <sys/statvfs.h>
+
+#ifndef UMOUNT_NOFOLLOW
+#define UMOUNT_NOFOLLOW    0x00000008  /* Don't follow symlink on umount */
+#endif
+
+using android::base::ReadFileToString;
+using android::base::StringPrintf;
+
+namespace android {
+namespace vold {
+
+security_context_t sBlkidContext = nullptr;
+security_context_t sBlkidUntrustedContext = nullptr;
+security_context_t sFsckContext = nullptr;
+security_context_t sFsckUntrustedContext = nullptr;
+
+static const char* kBlkidPath = "/system/bin/blkid";
+static const char* kKeyPath = "/data/misc/vold";
+
+static const char* kProcFilesystems = "/proc/filesystems";
+
+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) {
+            PLOG(ERROR) << "Failed to create device node for " << major(dev)
+                    << ":" << minor(dev) << " at " << path;
+            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 PrepareDir(const std::string& path, mode_t mode, uid_t uid, gid_t gid) {
+    const char* cpath = path.c_str();
+
+    char* secontext = nullptr;
+    if (sehandle) {
+        if (!selabel_lookup(sehandle, &secontext, cpath, S_IFDIR)) {
+            setfscreatecon(secontext);
+        }
+    }
+
+    int res = fs_prepare_dir(cpath, mode, uid, gid);
+
+    if (secontext) {
+        setfscreatecon(nullptr);
+        freecon(secontext);
+    }
+
+    if (res == 0) {
+        return OK;
+    } else {
+        return -errno;
+    }
+}
+
+status_t ForceUnmount(const std::string& path) {
+    const char* cpath = path.c_str();
+    if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+        return OK;
+    }
+    // Apps might still be handling eject request, so wait before
+    // we start sending signals
+    if (!VolumeManager::shutting_down) sleep(5);
+
+    Process::killProcessesWithOpenFiles(cpath, SIGINT);
+    if (!VolumeManager::shutting_down) sleep(5);
+    if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+        return OK;
+    }
+
+    Process::killProcessesWithOpenFiles(cpath, SIGTERM);
+    if (!VolumeManager::shutting_down) sleep(5);
+    if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+        return OK;
+    }
+
+    Process::killProcessesWithOpenFiles(cpath, SIGKILL);
+    if (!VolumeManager::shutting_down) sleep(5);
+    if (!umount2(cpath, UMOUNT_NOFOLLOW) || errno == EINVAL || errno == ENOENT) {
+        return OK;
+    }
+
+    return -errno;
+}
+
+status_t KillProcessesUsingPath(const std::string& path) {
+    const char* cpath = path.c_str();
+    if (Process::killProcessesWithOpenFiles(cpath, SIGINT) == 0) {
+        return OK;
+    }
+    if (!VolumeManager::shutting_down) sleep(5);
+
+    if (Process::killProcessesWithOpenFiles(cpath, SIGTERM) == 0) {
+        return OK;
+    }
+    if (!VolumeManager::shutting_down) sleep(5);
+
+    if (Process::killProcessesWithOpenFiles(cpath, SIGKILL) == 0) {
+        return OK;
+    }
+    if (!VolumeManager::shutting_down) sleep(5);
+
+    // Send SIGKILL a second time to determine if we've
+    // actually killed everyone with open files
+    if (Process::killProcessesWithOpenFiles(cpath, SIGKILL) == 0) {
+        return OK;
+    }
+    PLOG(ERROR) << "Failed to kill processes using " << path;
+    return -EBUSY;
+}
+
+status_t BindMount(const std::string& source, const std::string& target) {
+    if (::mount(source.c_str(), target.c_str(), "", MS_BIND, NULL)) {
+        PLOG(ERROR) << "Failed to bind mount " << source << " to " << target;
+        return -errno;
+    }
+    return OK;
+}
+
+static status_t readMetadata(const std::string& path, std::string& fsType,
+        std::string& fsUuid, std::string& fsLabel, bool untrusted) {
+    fsType.clear();
+    fsUuid.clear();
+    fsLabel.clear();
+
+    std::vector<std::string> cmd;
+    cmd.push_back(kBlkidPath);
+    cmd.push_back("-c");
+    cmd.push_back("/dev/null");
+    cmd.push_back("-s");
+    cmd.push_back("TYPE");
+    cmd.push_back("-s");
+    cmd.push_back("UUID");
+    cmd.push_back("-s");
+    cmd.push_back("LABEL");
+    cmd.push_back(path);
+
+    std::vector<std::string> output;
+    status_t res = ForkExecvp(cmd, output, untrusted ? sBlkidUntrustedContext : sBlkidContext);
+    if (res != OK) {
+        LOG(WARNING) << "blkid failed to identify " << path;
+        return res;
+    }
+
+    char value[128];
+    for (const auto& line : output) {
+        // Extract values from blkid output, if defined
+        const char* cline = line.c_str();
+        const char* start = strstr(cline, "TYPE=");
+        if (start != nullptr && sscanf(start + 5, "\"%127[^\"]\"", value) == 1) {
+            fsType = value;
+        }
+
+        start = strstr(cline, "UUID=");
+        if (start != nullptr && sscanf(start + 5, "\"%127[^\"]\"", value) == 1) {
+            fsUuid = value;
+        }
+
+        start = strstr(cline, "LABEL=");
+        if (start != nullptr && sscanf(start + 6, "\"%127[^\"]\"", value) == 1) {
+            fsLabel = value;
+        }
+    }
+
+    return OK;
+}
+
+status_t ReadMetadata(const std::string& path, std::string& fsType,
+        std::string& fsUuid, std::string& fsLabel) {
+    return readMetadata(path, fsType, fsUuid, fsLabel, false);
+}
+
+status_t ReadMetadataUntrusted(const std::string& path, std::string& fsType,
+        std::string& fsUuid, std::string& fsLabel) {
+    return readMetadata(path, fsType, fsUuid, fsLabel, true);
+}
+
+status_t ForkExecvp(const std::vector<std::string>& args) {
+    return ForkExecvp(args, nullptr);
+}
+
+status_t ForkExecvp(const std::vector<std::string>& args, security_context_t context) {
+    size_t argc = args.size();
+    char** argv = (char**) calloc(argc, sizeof(char*));
+    for (size_t i = 0; i < argc; i++) {
+        argv[i] = (char*) args[i].c_str();
+        if (i == 0) {
+            LOG(VERBOSE) << args[i];
+        } else {
+            LOG(VERBOSE) << "    " << args[i];
+        }
+    }
+
+    if (setexeccon(context)) {
+        LOG(ERROR) << "Failed to setexeccon";
+        abort();
+    }
+    status_t res = android_fork_execvp(argc, argv, NULL, false, true);
+    if (setexeccon(nullptr)) {
+        LOG(ERROR) << "Failed to setexeccon";
+        abort();
+    }
+
+    free(argv);
+    return res;
+}
+
+status_t ForkExecvp(const std::vector<std::string>& args,
+        std::vector<std::string>& output) {
+    return ForkExecvp(args, output, nullptr);
+}
+
+status_t ForkExecvp(const std::vector<std::string>& args,
+        std::vector<std::string>& output, security_context_t context) {
+    std::string cmd;
+    for (size_t i = 0; i < args.size(); i++) {
+        cmd += args[i] + " ";
+        if (i == 0) {
+            LOG(VERBOSE) << args[i];
+        } else {
+            LOG(VERBOSE) << "    " << args[i];
+        }
+    }
+    output.clear();
+
+    if (setexeccon(context)) {
+        LOG(ERROR) << "Failed to setexeccon";
+        abort();
+    }
+    FILE* fp = popen(cmd.c_str(), "r"); // NOLINT
+    if (setexeccon(nullptr)) {
+        LOG(ERROR) << "Failed to setexeccon";
+        abort();
+    }
+
+    if (!fp) {
+        PLOG(ERROR) << "Failed to popen " << cmd;
+        return -errno;
+    }
+    char line[1024];
+    while (fgets(line, sizeof(line), fp) != nullptr) {
+        LOG(VERBOSE) << line;
+        output.push_back(std::string(line));
+    }
+    if (pclose(fp) != 0) {
+        PLOG(ERROR) << "Failed to pclose " << cmd;
+        return -errno;
+    }
+
+    return OK;
+}
+
+pid_t ForkExecvpAsync(const std::vector<std::string>& args) {
+    size_t argc = args.size();
+    char** argv = (char**) calloc(argc + 1, sizeof(char*));
+    for (size_t i = 0; i < argc; i++) {
+        argv[i] = (char*) args[i].c_str();
+        if (i == 0) {
+            LOG(VERBOSE) << args[i];
+        } else {
+            LOG(VERBOSE) << "    " << args[i];
+        }
+    }
+
+    pid_t pid = fork();
+    if (pid == 0) {
+        close(STDIN_FILENO);
+        close(STDOUT_FILENO);
+        close(STDERR_FILENO);
+
+        if (execvp(argv[0], argv)) {
+            PLOG(ERROR) << "Failed to exec";
+        }
+
+        _exit(1);
+    }
+
+    if (pid == -1) {
+        PLOG(ERROR) << "Failed to exec";
+    }
+
+    free(argv);
+    return pid;
+}
+
+status_t ReadRandomBytes(size_t bytes, std::string& out) {
+    out.resize(bytes);
+    return ReadRandomBytes(bytes, &out[0]);
+}
+
+status_t ReadRandomBytes(size_t bytes, char* buf) {
+    int fd = TEMP_FAILURE_RETRY(open("/dev/urandom", O_RDONLY | O_CLOEXEC | O_NOFOLLOW));
+    if (fd == -1) {
+        return -errno;
+    }
+
+    size_t n;
+    while ((n = TEMP_FAILURE_RETRY(read(fd, &buf[0], bytes))) > 0) {
+        bytes -= n;
+        buf += n;
+    }
+    close(fd);
+
+    if (bytes == 0) {
+        return OK;
+    } else {
+        return -EIO;
+    }
+}
+
+status_t GenerateRandomUuid(std::string& out) {
+    status_t res = ReadRandomBytes(16, out);
+    if (res == OK) {
+        out[6] &= 0x0f;  /* clear version        */
+        out[6] |= 0x40;  /* set to version 4     */
+        out[8] &= 0x3f;  /* clear variant        */
+        out[8] |= 0x80;  /* set to IETF variant  */
+    }
+    return res;
+}
+
+status_t HexToStr(const std::string& hex, std::string& str) {
+    str.clear();
+    bool even = true;
+    char cur = 0;
+    for (size_t i = 0; i < hex.size(); i++) {
+        int val = 0;
+        switch (hex[i]) {
+        case ' ': case '-': case ':': continue;
+        case 'f': case 'F': val = 15; break;
+        case 'e': case 'E': val = 14; break;
+        case 'd': case 'D': val = 13; break;
+        case 'c': case 'C': val = 12; break;
+        case 'b': case 'B': val = 11; break;
+        case 'a': case 'A': val = 10; break;
+        case '9': val = 9; break;
+        case '8': val = 8; break;
+        case '7': val = 7; break;
+        case '6': val = 6; break;
+        case '5': val = 5; break;
+        case '4': val = 4; break;
+        case '3': val = 3; break;
+        case '2': val = 2; break;
+        case '1': val = 1; break;
+        case '0': val = 0; break;
+        default: return -EINVAL;
+        }
+
+        if (even) {
+            cur = val << 4;
+        } else {
+            cur += val;
+            str.push_back(cur);
+            cur = 0;
+        }
+        even = !even;
+    }
+    return even ? OK : -EINVAL;
+}
+
+static const char* kLookup = "0123456789abcdef";
+
+status_t StrToHex(const std::string& str, std::string& hex) {
+    hex.clear();
+    for (size_t i = 0; i < str.size(); i++) {
+        hex.push_back(kLookup[(str[i] & 0xF0) >> 4]);
+        hex.push_back(kLookup[str[i] & 0x0F]);
+    }
+    return OK;
+}
+
+status_t StrToHex(const KeyBuffer& str, KeyBuffer& hex) {
+    hex.clear();
+    for (size_t i = 0; i < str.size(); i++) {
+        hex.push_back(kLookup[(str.data()[i] & 0xF0) >> 4]);
+        hex.push_back(kLookup[str.data()[i] & 0x0F]);
+    }
+    return OK;
+}
+
+status_t NormalizeHex(const std::string& in, std::string& out) {
+    std::string tmp;
+    if (HexToStr(in, tmp)) {
+        return -EINVAL;
+    }
+    return StrToHex(tmp, out);
+}
+
+uint64_t GetFreeBytes(const std::string& path) {
+    struct statvfs sb;
+    if (statvfs(path.c_str(), &sb) == 0) {
+        return (uint64_t) sb.f_bavail * sb.f_frsize;
+    } else {
+        return -1;
+    }
+}
+
+// TODO: borrowed from frameworks/native/libs/diskusage/ which should
+// eventually be migrated into system/
+static int64_t stat_size(struct stat *s) {
+    int64_t blksize = s->st_blksize;
+    // count actual blocks used instead of nominal file size
+    int64_t size = s->st_blocks * 512;
+
+    if (blksize) {
+        /* round up to filesystem block size */
+        size = (size + blksize - 1) & (~(blksize - 1));
+    }
+
+    return size;
+}
+
+// TODO: borrowed from frameworks/native/libs/diskusage/ which should
+// eventually be migrated into system/
+int64_t calculate_dir_size(int dfd) {
+    int64_t size = 0;
+    struct stat s;
+    DIR *d;
+    struct dirent *de;
+
+    d = fdopendir(dfd);
+    if (d == NULL) {
+        close(dfd);
+        return 0;
+    }
+
+    while ((de = readdir(d))) {
+        const char *name = de->d_name;
+        if (fstatat(dfd, name, &s, AT_SYMLINK_NOFOLLOW) == 0) {
+            size += stat_size(&s);
+        }
+        if (de->d_type == DT_DIR) {
+            int subfd;
+
+            /* always skip "." and ".." */
+            if (name[0] == '.') {
+                if (name[1] == 0)
+                    continue;
+                if ((name[1] == '.') && (name[2] == 0))
+                    continue;
+            }
+
+            subfd = openat(dfd, name, O_RDONLY | O_DIRECTORY | O_CLOEXEC);
+            if (subfd >= 0) {
+                size += calculate_dir_size(subfd);
+            }
+        }
+    }
+    closedir(d);
+    return size;
+}
+
+uint64_t GetTreeBytes(const std::string& path) {
+    int dirfd = open(path.c_str(), O_RDONLY | O_DIRECTORY | O_CLOEXEC);
+    if (dirfd < 0) {
+        PLOG(WARNING) << "Failed to open " << path;
+        return -1;
+    } else {
+        uint64_t res = calculate_dir_size(dirfd);
+        close(dirfd);
+        return res;
+    }
+}
+
+bool IsFilesystemSupported(const std::string& fsType) {
+    std::string supported;
+    if (!ReadFileToString(kProcFilesystems, &supported)) {
+        PLOG(ERROR) << "Failed to read supported filesystems";
+        return false;
+    }
+    return supported.find(fsType + "\n") != std::string::npos;
+}
+
+status_t WipeBlockDevice(const std::string& path) {
+    status_t res = -1;
+    const char* c_path = path.c_str();
+    unsigned long nr_sec = 0;
+    unsigned long long range[2];
+
+    int fd = TEMP_FAILURE_RETRY(open(c_path, O_RDWR | O_CLOEXEC));
+    if (fd == -1) {
+        PLOG(ERROR) << "Failed to open " << path;
+        goto done;
+    }
+
+    if ((ioctl(fd, BLKGETSIZE, &nr_sec)) == -1) {
+        PLOG(ERROR) << "Failed to determine size of " << path;
+        goto done;
+    }
+
+    range[0] = 0;
+    range[1] = (unsigned long long) nr_sec * 512;
+
+    LOG(INFO) << "About to discard " << range[1] << " on " << path;
+    if (ioctl(fd, BLKDISCARD, &range) == 0) {
+        LOG(INFO) << "Discard success on " << path;
+        res = 0;
+    } else {
+        PLOG(ERROR) << "Discard failure on " << path;
+    }
+
+done:
+    close(fd);
+    return res;
+}
+
+static bool isValidFilename(const std::string& name) {
+    if (name.empty() || (name == ".") || (name == "..")
+            || (name.find('/') != std::string::npos)) {
+        return false;
+    } else {
+        return true;
+    }
+}
+
+std::string BuildKeyPath(const std::string& partGuid) {
+    return StringPrintf("%s/expand_%s.key", kKeyPath, partGuid.c_str());
+}
+
+std::string BuildDataSystemLegacyPath(userid_t userId) {
+    return StringPrintf("%s/system/users/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+std::string BuildDataSystemCePath(userid_t userId) {
+    return StringPrintf("%s/system_ce/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+std::string BuildDataSystemDePath(userid_t userId) {
+    return StringPrintf("%s/system_de/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+std::string BuildDataMiscLegacyPath(userid_t userId) {
+    return StringPrintf("%s/misc/user/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+std::string BuildDataMiscCePath(userid_t userId) {
+    return StringPrintf("%s/misc_ce/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+std::string BuildDataMiscDePath(userid_t userId) {
+    return StringPrintf("%s/misc_de/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+// Keep in sync with installd (frameworks/native/cmds/installd/utils.h)
+std::string BuildDataProfilesDePath(userid_t userId) {
+    return StringPrintf("%s/misc/profiles/cur/%u", BuildDataPath(nullptr).c_str(), userId);
+}
+
+std::string BuildDataPath(const char* volumeUuid) {
+    // TODO: unify with installd path generation logic
+    if (volumeUuid == nullptr) {
+        return "/data";
+    } else {
+        CHECK(isValidFilename(volumeUuid));
+        return StringPrintf("/mnt/expand/%s", volumeUuid);
+    }
+}
+
+std::string BuildDataMediaCePath(const char* volumeUuid, userid_t userId) {
+    // TODO: unify with installd path generation logic
+    std::string data(BuildDataPath(volumeUuid));
+    return StringPrintf("%s/media/%u", data.c_str(), userId);
+}
+
+std::string BuildDataUserCePath(const char* volumeUuid, userid_t userId) {
+    // TODO: unify with installd path generation logic
+    std::string data(BuildDataPath(volumeUuid));
+    if (volumeUuid == nullptr && userId == 0) {
+        std::string legacy = StringPrintf("%s/data", data.c_str());
+        struct stat sb;
+        if (lstat(legacy.c_str(), &sb) == 0 && S_ISDIR(sb.st_mode)) {
+            /* /data/data is dir, return /data/data for legacy system */
+            return legacy;
+        }
+    }
+    return StringPrintf("%s/user/%u", data.c_str(), userId);
+}
+
+std::string BuildDataUserDePath(const char* volumeUuid, userid_t userId) {
+    // TODO: unify with installd path generation logic
+    std::string data(BuildDataPath(volumeUuid));
+    return StringPrintf("%s/user_de/%u", data.c_str(), userId);
+}
+
+dev_t GetDevice(const std::string& path) {
+    struct stat sb;
+    if (stat(path.c_str(), &sb)) {
+        PLOG(WARNING) << "Failed to stat " << path;
+        return 0;
+    } else {
+        return sb.st_dev;
+    }
+}
+
+status_t RestoreconRecursive(const std::string& path) {
+    LOG(VERBOSE) << "Starting restorecon of " << path;
+
+    static constexpr const char* kRestoreconString = "selinux.restorecon_recursive";
+
+    android::base::SetProperty(kRestoreconString, "");
+    android::base::SetProperty(kRestoreconString, path);
+
+    android::base::WaitForProperty(kRestoreconString, path);
+
+    LOG(VERBOSE) << "Finished restorecon of " << path;
+    return OK;
+}
+
+status_t SaneReadLinkAt(int dirfd, const char* path, char* buf, size_t bufsiz) {
+    ssize_t len = readlinkat(dirfd, path, buf, bufsiz);
+    if (len < 0) {
+        return -1;
+    } else if (len == (ssize_t) bufsiz) {
+        return -1;
+    } else {
+        buf[len] = '\0';
+        return 0;
+    }
+}
+
+bool IsRunningInEmulator() {
+    return android::base::GetBoolProperty("ro.kernel.qemu", false);
+}
+
+}  // namespace vold
+}  // namespace android