/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.server.pm;
import android.annotation.NonNull;
import android.annotation.UserIdInt;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManagerInternal;
import android.content.pm.ShortcutInfo;
import android.content.pm.Signature;
import android.content.pm.SigningInfo;
import android.util.Slog;
import com.android.internal.annotations.VisibleForTesting;
import com.android.server.LocalServices;
import com.android.server.backup.BackupUtils;
import libcore.util.HexEncoding;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlSerializer;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Base64;
/**
* Package information used by {@link android.content.pm.ShortcutManager} for backup / restore.
*
* All methods should be guarded by {@code ShortcutService.mLock}.
*/
class ShortcutPackageInfo {
private static final String TAG = ShortcutService.TAG;
static final String TAG_ROOT = "package-info";
private static final String ATTR_VERSION = "version";
private static final String ATTR_LAST_UPDATE_TIME = "last_udpate_time";
private static final String ATTR_BACKUP_SOURCE_VERSION = "bk_src_version";
private static final String ATTR_BACKUP_ALLOWED = "allow-backup";
private static final String ATTR_BACKUP_ALLOWED_INITIALIZED = "allow-backup-initialized";
private static final String ATTR_BACKUP_SOURCE_BACKUP_ALLOWED = "bk_src_backup-allowed";
private static final String ATTR_SHADOW = "shadow";
private static final String TAG_SIGNATURE = "signature";
private static final String ATTR_SIGNATURE_HASH = "hash";
/**
* When true, this package information was restored from the previous device, and the app hasn't
* been installed yet.
*/
private boolean mIsShadow;
private long mVersionCode = ShortcutInfo.VERSION_CODE_UNKNOWN;
private long mBackupSourceVersionCode = ShortcutInfo.VERSION_CODE_UNKNOWN;
private long mLastUpdateTime;
private ArrayList<byte[]> mSigHashes;
// mBackupAllowed didn't used to be parsisted, so we don't restore it from a file.
// mBackupAllowed will always start with false, and will have been updated before making a
// backup next time, which works file.
// We just don't want to print an uninitialzied mBackupAlldowed value on dumpsys, so
// we use this boolean to control dumpsys.
private boolean mBackupAllowedInitialized;
private boolean mBackupAllowed;
private boolean mBackupSourceBackupAllowed;
private ShortcutPackageInfo(long versionCode, long lastUpdateTime,
ArrayList<byte[]> sigHashes, boolean isShadow) {
mVersionCode = versionCode;
mLastUpdateTime = lastUpdateTime;
mIsShadow = isShadow;
mSigHashes = sigHashes;
mBackupAllowed = false; // By default, we assume false.
mBackupSourceBackupAllowed = false;
}
public static ShortcutPackageInfo newEmpty() {
return new ShortcutPackageInfo(ShortcutInfo.VERSION_CODE_UNKNOWN, /* last update time =*/ 0,
new ArrayList<>(0), /* isShadow */ false);
}
public boolean isShadow() {
return mIsShadow;
}
public void setShadow(boolean shadow) {
mIsShadow = shadow;
}
public long getVersionCode() {
return mVersionCode;
}
public long getBackupSourceVersionCode() {
return mBackupSourceVersionCode;
}
@VisibleForTesting
public boolean isBackupSourceBackupAllowed() {
return mBackupSourceBackupAllowed;
}
public long getLastUpdateTime() {
return mLastUpdateTime;
}
public boolean isBackupAllowed() {
return mBackupAllowed;
}
/**
* Set {@link #mVersionCode}, {@link #mLastUpdateTime} and {@link #mBackupAllowed}
* from a {@link PackageInfo}.
*/
public void updateFromPackageInfo(@NonNull PackageInfo pi) {
if (pi != null) {
mVersionCode = pi.getLongVersionCode();
mLastUpdateTime = pi.lastUpdateTime;
mBackupAllowed = ShortcutService.shouldBackupApp(pi);
mBackupAllowedInitialized = true;
}
}
public boolean hasSignatures() {
return mSigHashes.size() > 0;
}
//@DisabledReason
public int canRestoreTo(ShortcutService s, PackageInfo currentPackage, boolean anyVersionOkay) {
PackageManagerInternal pmi = LocalServices.getService(PackageManagerInternal.class);
if (!BackupUtils.signaturesMatch(mSigHashes, currentPackage, pmi)) {
Slog.w(TAG, "Can't restore: Package signature mismatch");
return ShortcutInfo.DISABLED_REASON_SIGNATURE_MISMATCH;
}
if (!ShortcutService.shouldBackupApp(currentPackage) || !mBackupSourceBackupAllowed) {
// "allowBackup" was true when backed up, but now false.
Slog.w(TAG, "Can't restore: package didn't or doesn't allow backup");
return ShortcutInfo.DISABLED_REASON_BACKUP_NOT_SUPPORTED;
}
if (!anyVersionOkay && (currentPackage.getLongVersionCode() < mBackupSourceVersionCode)) {
Slog.w(TAG, String.format(
"Can't restore: package current version %d < backed up version %d",
currentPackage.getLongVersionCode(), mBackupSourceVersionCode));
return ShortcutInfo.DISABLED_REASON_VERSION_LOWER;
}
return ShortcutInfo.DISABLED_REASON_NOT_DISABLED;
}
@VisibleForTesting
public static ShortcutPackageInfo generateForInstalledPackageForTest(
ShortcutService s, String packageName, @UserIdInt int packageUserId) {
final PackageInfo pi = s.getPackageInfoWithSignatures(packageName, packageUserId);
// retrieve the newest sigs
SigningInfo signingInfo = pi.signingInfo;
if (signingInfo == null) {
Slog.e(TAG, "Can't get signatures: package=" + packageName);
return null;
}
// TODO (b/73988180) use entire signing history in case of rollbacks
Signature[] signatures = signingInfo.getApkContentsSigners();
final ShortcutPackageInfo ret = new ShortcutPackageInfo(pi.getLongVersionCode(),
pi.lastUpdateTime, BackupUtils.hashSignatureArray(signatures), /* shadow=*/ false);
ret.mBackupSourceBackupAllowed = s.shouldBackupApp(pi);
ret.mBackupSourceVersionCode = pi.getLongVersionCode();
return ret;
}
public void refreshSignature(ShortcutService s, ShortcutPackageItem pkg) {
if (mIsShadow) {
s.wtf("Attempted to refresh package info for shadow package " + pkg.getPackageName()
+ ", user=" + pkg.getOwnerUserId());
return;
}
// Note use mUserId here, rather than userId.
final PackageInfo pi = s.getPackageInfoWithSignatures(
pkg.getPackageName(), pkg.getPackageUserId());
if (pi == null) {
Slog.w(TAG, "Package not found: " + pkg.getPackageName());
return;
}
// retrieve the newest sigs
SigningInfo signingInfo = pi.signingInfo;
if (signingInfo == null) {
Slog.w(TAG, "Not refreshing signature for " + pkg.getPackageName()
+ " since it appears to have no signing info.");
return;
}
// TODO (b/73988180) use entire signing history in case of rollbacks
Signature[] signatures = signingInfo.getApkContentsSigners();
mSigHashes = BackupUtils.hashSignatureArray(signatures);
}
public void saveToXml(ShortcutService s, XmlSerializer out, boolean forBackup)
throws IOException {
if (forBackup && !mBackupAllowedInitialized) {
s.wtf("Backup happened before mBackupAllowed is initialized.");
}
out.startTag(null, TAG_ROOT);
ShortcutService.writeAttr(out, ATTR_VERSION, mVersionCode);
ShortcutService.writeAttr(out, ATTR_LAST_UPDATE_TIME, mLastUpdateTime);
ShortcutService.writeAttr(out, ATTR_SHADOW, mIsShadow);
ShortcutService.writeAttr(out, ATTR_BACKUP_ALLOWED, mBackupAllowed);
// We don't need to save this field (we don't even read it back), but it'll show up
// in the dumpsys in the backup / restore payload.
ShortcutService.writeAttr(out, ATTR_BACKUP_ALLOWED_INITIALIZED, mBackupAllowedInitialized);
ShortcutService.writeAttr(out, ATTR_BACKUP_SOURCE_VERSION, mBackupSourceVersionCode);
ShortcutService.writeAttr(out,
ATTR_BACKUP_SOURCE_BACKUP_ALLOWED, mBackupSourceBackupAllowed);
for (int i = 0; i < mSigHashes.size(); i++) {
out.startTag(null, TAG_SIGNATURE);
final String encoded = Base64.getEncoder().encodeToString(mSigHashes.get(i));
ShortcutService.writeAttr(out, ATTR_SIGNATURE_HASH, encoded);
out.endTag(null, TAG_SIGNATURE);
}
out.endTag(null, TAG_ROOT);
}
public void loadFromXml(XmlPullParser parser, boolean fromBackup)
throws IOException, XmlPullParserException {
// Don't use the version code from the backup file.
final long versionCode = ShortcutService.parseLongAttribute(parser, ATTR_VERSION,
ShortcutInfo.VERSION_CODE_UNKNOWN);
final long lastUpdateTime = ShortcutService.parseLongAttribute(
parser, ATTR_LAST_UPDATE_TIME);
// When restoring from backup, it's always shadow.
final boolean shadow =
fromBackup || ShortcutService.parseBooleanAttribute(parser, ATTR_SHADOW);
// We didn't used to save these attributes, and all backed up shortcuts were from
// apps that support backups, so the default values take this fact into consideration.
final long backupSourceVersion = ShortcutService.parseLongAttribute(parser,
ATTR_BACKUP_SOURCE_VERSION, ShortcutInfo.VERSION_CODE_UNKNOWN);
// Note the only time these "true" default value is used is when restoring from an old
// build that didn't save ATTR_BACKUP_ALLOWED, and that means all the data included in
// a backup file were from apps that support backup, so we can just use "true" as the
// default.
final boolean backupAllowed = ShortcutService.parseBooleanAttribute(
parser, ATTR_BACKUP_ALLOWED, true);
final boolean backupSourceBackupAllowed = ShortcutService.parseBooleanAttribute(
parser, ATTR_BACKUP_SOURCE_BACKUP_ALLOWED, true);
final ArrayList<byte[]> hashes = new ArrayList<>();
final int outerDepth = parser.getDepth();
int type;
while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
&& (type != XmlPullParser.END_TAG || parser.getDepth() > outerDepth)) {
if (type != XmlPullParser.START_TAG) {
continue;
}
final int depth = parser.getDepth();
final String tag = parser.getName();
if (depth == outerDepth + 1) {
switch (tag) {
case TAG_SIGNATURE: {
final String hash = ShortcutService.parseStringAttribute(
parser, ATTR_SIGNATURE_HASH);
// Throws IllegalArgumentException if hash is invalid base64 data
final byte[] decoded = Base64.getDecoder().decode(hash);
hashes.add(decoded);
continue;
}
}
}
ShortcutService.warnForInvalidTag(depth, tag);
}
// Successfully loaded; replace the fields.
if (fromBackup) {
mVersionCode = ShortcutInfo.VERSION_CODE_UNKNOWN;
mBackupSourceVersionCode = versionCode;
mBackupSourceBackupAllowed = backupAllowed;
} else {
mVersionCode = versionCode;
mBackupSourceVersionCode = backupSourceVersion;
mBackupSourceBackupAllowed = backupSourceBackupAllowed;
}
mLastUpdateTime = lastUpdateTime;
mIsShadow = shadow;
mSigHashes = hashes;
// Note we don't restore it from the file because it didn't used to be saved.
// We always start by assuming backup is disabled for the current package,
// and this field will have been updated before we actually create a backup, at the same
// time when we update the version code.
// Until then, the value of mBackupAllowed shouldn't matter, but we don't want to print
// a false flag on dumpsys, so set mBackupAllowedInitialized to false.
mBackupAllowed = false;
mBackupAllowedInitialized = false;
}
public void dump(PrintWriter pw, String prefix) {
pw.println();
pw.print(prefix);
pw.println("PackageInfo:");
pw.print(prefix);
pw.print(" IsShadow: ");
pw.print(mIsShadow);
pw.print(mIsShadow ? " (not installed)" : " (installed)");
pw.println();
pw.print(prefix);
pw.print(" Version: ");
pw.print(mVersionCode);
pw.println();
if (mBackupAllowedInitialized) {
pw.print(prefix);
pw.print(" Backup Allowed: ");
pw.print(mBackupAllowed);
pw.println();
}
if (mBackupSourceVersionCode != ShortcutInfo.VERSION_CODE_UNKNOWN) {
pw.print(prefix);
pw.print(" Backup source version: ");
pw.print(mBackupSourceVersionCode);
pw.println();
pw.print(prefix);
pw.print(" Backup source backup allowed: ");
pw.print(mBackupSourceBackupAllowed);
pw.println();
}
pw.print(prefix);
pw.print(" Last package update time: ");
pw.print(mLastUpdateTime);
pw.println();
for (int i = 0; i < mSigHashes.size(); i++) {
pw.print(prefix);
pw.print(" ");
pw.print("SigHash: ");
pw.println(HexEncoding.encode(mSigHashes.get(i)));
}
}
}