Android/frameworks_base
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add some global metadata to the restore set

Browse Source 
In addition to the signatures of each participating application, we now also
store the versionCode of each backed-up package, plus the OS version running on
the device that contributed the backup set.  We also refuse to process a backup
from a later OS revision to an earlier one, or from a later app version to an
earlier.

LocalTransport has been modified as well to be more resilient to changes in the
system's use of metadata pseudopackages.
This commit is contained in:
Christopher Tate
2009-06-22 15:10:30 -07:00
parent e146d82478
commit 3a31a93b8a
3 changed files with 171 additions and 95 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
core/java/com/android/internal/backup/LocalTransport.java
View File

@@ -170,18 +170,13 @@ public class LocalTransport extends IBackupTransport.Stub {
// The restore set is the concatenation of the individual record blobs,
// each of which is a file in the package's directory
File[] blobs = packageDir.listFiles();
if (DEBUG) Log.v(TAG, " found " + blobs.length + " key files");
int err = 0;
if (blobs != null && blobs.length > 0) {
BackupDataOutput out = new BackupDataOutput(outFd.getFileDescriptor());
try {
for (File f : blobs) {
FileInputStream in = new FileInputStream(f);
int size = (int) f.length();
byte[] buf = new byte[size];
in.read(buf);
String key = new String(Base64.decode(f.getName()));
out.writeEntityHeader(key, size);
out.writeEntityData(buf, size);
copyToRestoreData(f, out);
}
} catch (Exception e) {
Log.e(TAG, "Unable to read backup records");
@@ -190,4 +185,16 @@ public class LocalTransport extends IBackupTransport.Stub {
}
return err;
}
private void copyToRestoreData(File f, BackupDataOutput out) throws IOException {
FileInputStream in = new FileInputStream(f);
int size = (int) f.length();
byte[] buf = new byte[size];
in.read(buf);
String key = new String(Base64.decode(f.getName()));
if (DEBUG) Log.v(TAG, " ... copy to stream: key=" + key
+ " size=" + size);
out.writeEntityHeader(key, size);
out.writeEntityData(buf, size);
}
}

28
services/java/com/android/server/BackupManagerService.java
View File

@@ -34,6 +34,7 @@ import android.content.pm.PackageManager;
import android.content.pm.Signature;
import android.net.Uri;
import android.os.Binder;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
@@ -850,18 +851,27 @@ class BackupManagerService extends IBackupManager.Stub {
if (app != null) {
// Validate against the backed-up signature block, too
Metadata info = pmAgent.getRestoredMetadata(app.packageName);
if (app.versionCode >= info.versionCode) {
if (DEBUG) Log.v(TAG, "Restore version " + info.versionCode
+ " compatible with app version " + app.versionCode);
if (signaturesMatch(info.signatures, app.signatures)) {
appsToRestore.add(app);
if (info != null) {
if (app.versionCode >= info.versionCode) {
if (DEBUG) Log.v(TAG, "Restore version "
+ info.versionCode
+ " compatible with app version "
+ app.versionCode);
if (signaturesMatch(info.signatures, app.signatures)) {
appsToRestore.add(app);
} else {
Log.w(TAG, "Sig mismatch restoring "
+ app.packageName);
}
} else {
Log.w(TAG, "Sig mismatch restoring " + app.packageName);
Log.i(TAG, "Restore set for " + app.packageName
+ " is too new [" + info.versionCode
+ "] for installed app version "
+ app.versionCode);
}
} else {
Log.i(TAG, "Restore set for " + app.packageName
+ " is too new [" + info.versionCode
+ "] for installed app version " + app.versionCode);
Log.d(TAG, "Unable to get metadata for "
+ app.packageName);
}
}
}

217
services/java/com/android/server/PackageManagerBackupAgent.java
View File

@@ -24,6 +24,7 @@ import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.content.pm.Signature;
import android.os.Build;
import android.os.ParcelFileDescriptor;
import android.util.Log;
@@ -52,6 +53,10 @@ public class PackageManagerBackupAgent extends BackupAgent {
private static final String TAG = "PMBA";
private static final boolean DEBUG = true;
// key under which we store global metadata (individual app metadata
// is stored using the package name as a key)
private static final String GLOBAL_METADATA_KEY = "@meta@";
private List<ApplicationInfo> mAllApps;
private PackageManager mPackageManager;
private HashMap<String, Metadata> mRestoredSignatures;
@@ -76,6 +81,7 @@ public class PackageManagerBackupAgent extends BackupAgent {
public Metadata getRestoredMetadata(String packageName) {
if (mRestoredSignatures == null) {
Log.w(TAG, "getRestoredMetadata() before metadata read!");
return null;
}
@@ -86,74 +92,97 @@ public class PackageManagerBackupAgent extends BackupAgent {
// the package name.
public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
ParcelFileDescriptor newState) {
HashSet<String> existing = parseStateFile(oldState);
// For each app we have on device, see if we've backed it up yet. If not,
// write its signature block to the output, keyed on the package name.
if (DEBUG) Log.v(TAG, "onBackup()");
ByteArrayOutputStream bufStream = new ByteArrayOutputStream(); // we'll reuse these
DataOutputStream outWriter = new DataOutputStream(bufStream);
for (ApplicationInfo app : mAllApps) {
String packName = app.packageName;
if (!existing.contains(packName)) {
// We haven't stored this app's signatures yet, so we do that now
try {
PackageInfo info = mPackageManager.getPackageInfo(packName,
PackageManager.GET_SIGNATURES);
/*
* Metadata for each package:
*
* int version -- [4] the package's versionCode
* byte[] signatures -- [len] flattened Signature[] of the package
*/
HashSet<String> existing = parseStateFile(oldState);
// marshall the version code in a canonical form
bufStream.reset();
outWriter.writeInt(info.versionCode);
byte[] versionBuf = bufStream.toByteArray();
try {
/*
* Global metadata:
*
* int version -- the SDK version of the OS itself on the device
* that produced this backup set. Used to reject
* backups from later OSes onto earlier ones.
*/
if (!existing.contains(GLOBAL_METADATA_KEY)) {
if (DEBUG) Log.v(TAG, "Storing global metadata key");
outWriter.writeInt(Build.VERSION.SDK_INT);
byte[] metadata = bufStream.toByteArray();
data.writeEntityHeader(GLOBAL_METADATA_KEY, metadata.length);
data.writeEntityData(metadata, metadata.length);
} else {
if (DEBUG) Log.v(TAG, "Global metadata key already stored");
}
byte[] sigs = flattenSignatureArray(info.signatures);
// For each app we have on device, see if we've backed it up yet. If not,
// write its signature block to the output, keyed on the package name.
for (ApplicationInfo app : mAllApps) {
String packName = app.packageName;
if (!existing.contains(packName)) {
// We haven't stored this app's signatures yet, so we do that now
try {
PackageInfo info = mPackageManager.getPackageInfo(packName,
PackageManager.GET_SIGNATURES);
/*
* Metadata for each package:
*
* int version -- [4] the package's versionCode
* byte[] signatures -- [len] flattened Signature[] of the package
*/
// !!! TODO: take out this debugging
if (DEBUG) {
Log.v(TAG, "+ metadata for " + packName + " version=" + info.versionCode);
// marshall the version code in a canonical form
bufStream.reset();
outWriter.writeInt(info.versionCode);
byte[] versionBuf = bufStream.toByteArray();
byte[] sigs = flattenSignatureArray(info.signatures);
// !!! TODO: take out this debugging
if (DEBUG) {
Log.v(TAG, "+ metadata for " + packName
+ " version=" + info.versionCode
+ " versionLen=" + versionBuf.length
+ " sigsLen=" + sigs.length);
}
// Now we can write the backup entity for this package
data.writeEntityHeader(packName, versionBuf.length + sigs.length);
data.writeEntityData(versionBuf, versionBuf.length);
data.writeEntityData(sigs, sigs.length);
} catch (NameNotFoundException e) {
// Weird; we just found it, and now are told it doesn't exist.
// Treat it as having been removed from the device.
existing.add(packName);
}
// Now we can write the backup entity for this package
data.writeEntityHeader(packName, versionBuf.length + sigs.length);
data.writeEntityData(versionBuf, versionBuf.length);
data.writeEntityData(sigs, sigs.length);
} catch (NameNotFoundException e) {
// Weird; we just found it, and now are told it doesn't exist.
// Treat it as having been removed from the device.
existing.add(packName);
} else {
// We've already backed up this app. Remove it from the set so
// we can tell at the end what has disappeared from the device.
// !!! TODO: take out the debugging message
if (DEBUG) Log.v(TAG, "= already backed up metadata for " + packName);
if (!existing.remove(packName)) {
Log.d(TAG, "*** failed to remove " + packName + " from package set!");
}
}
}
// At this point, the only entries in 'existing' are apps that were
// mentioned in the saved state file, but appear to no longer be present
// on the device. Write a deletion entity for them.
for (String app : existing) {
// !!! TODO: take out this msg
if (DEBUG) Log.v(TAG, "- removing metadata for deleted pkg " + app);
try {
data.writeEntityHeader(app, -1);
} catch (IOException e) {
// Real error writing data
Log.e(TAG, "Unable to write package backup data file!");
Log.e(TAG, "Unable to write package deletions!");
return;
}
} else {
// We've already backed up this app. Remove it from the set so
// we can tell at the end what has disappeared from the device.
// !!! TODO: take out the debugging message
if (DEBUG) Log.v(TAG, "= already backed up metadata for " + packName);
if (!existing.remove(packName)) {
Log.d(TAG, "*** failed to remove " + packName + " from package set!");
}
}
}
// At this point, the only entries in 'existing' are apps that were
// mentioned in the saved state file, but appear to no longer be present
// on the device. Write a deletion entity for them.
for (String app : existing) {
// !!! TODO: take out this msg
if (DEBUG) Log.v(TAG, "- removing metadata for deleted pkg " + app);
try {
data.writeEntityHeader(app, -1);
} catch (IOException e) {
Log.e(TAG, "Unable to write package deletions!");
return;
}
} catch (IOException e) {
// Real error writing data
Log.e(TAG, "Unable to write package backup data file!");
return;
}
// Finally, write the new state blob -- just the list of all apps we handled
@@ -167,30 +196,53 @@ public class PackageManagerBackupAgent extends BackupAgent {
throws IOException {
List<ApplicationInfo> restoredApps = new ArrayList<ApplicationInfo>();
HashMap<String, Metadata> sigMap = new HashMap<String, Metadata>();
if (DEBUG) Log.v(TAG, "onRestore()");
int storedSystemVersion = -1;
while (data.readNextHeader()) {
String key = data.getKey();
int dataSize = data.getDataSize();
byte[] buf = new byte[dataSize];
data.readEntityData(buf, 0, dataSize);
ByteArrayInputStream bufStream = new ByteArrayInputStream(buf);
DataInputStream in = new DataInputStream(bufStream);
int versionCode = in.readInt();
if (DEBUG) Log.v(TAG, " got key=" + key + " dataSize=" + dataSize);
Signature[] sigs = unflattenSignatureArray(in);
String pkg = data.getKey();
// !!! TODO: take out this debugging
if (DEBUG) {
Log.i(TAG, "+ restored metadata for " + pkg
+ " versionCode=" + versionCode + " sigs=" + sigs);
// generic setup to parse any entity data
byte[] dataBuf = new byte[dataSize];
data.readEntityData(dataBuf, 0, dataSize);
ByteArrayInputStream baStream = new ByteArrayInputStream(dataBuf);
DataInputStream in = new DataInputStream(baStream);
if (key.equals(GLOBAL_METADATA_KEY)) {
storedSystemVersion = in.readInt();
if (DEBUG) Log.v(TAG, " storedSystemVersion = " + storedSystemVersion);
if (storedSystemVersion > Build.VERSION.SDK_INT) {
// returning before setting the sig map means we rejected the restore set
Log.w(TAG, "Restore set was from a later version of Android; not restoring");
return;
}
// !!! TODO: remove this debugging output
if (DEBUG) {
Log.i(TAG, "Restore set version " + storedSystemVersion
+ " is compatible with OS version " + Build.VERSION.SDK_INT);
}
} else {
// it's a file metadata record
int versionCode = in.readInt();
Signature[] sigs = unflattenSignatureArray(in);
// !!! TODO: take out this debugging
if (DEBUG) {
Log.i(TAG, " restored metadata for " + key
+ " dataSize=" + dataSize
+ " versionCode=" + versionCode + " sigs=" + sigs);
}
ApplicationInfo app = new ApplicationInfo();
app.packageName = key;
restoredApps.add(app);
sigMap.put(key, new Metadata(versionCode, sigs));
}
ApplicationInfo app = new ApplicationInfo();
app.packageName = pkg;
restoredApps.add(app);
sigMap.put(pkg, new Metadata(versionCode, sigs));
}
// On successful completion, cache the signature map for the Backup Manager to use
mRestoredSignatures = sigMap;
}
@@ -225,6 +277,7 @@ public class PackageManagerBackupAgent extends BackupAgent {
try {
int num = in.readInt();
Log.v(TAG, " ... unflatten read " + num);
sigs = new Signature[num];
for (int i = 0; i < num; i++) {
int len = in.readInt();
@@ -273,20 +326,26 @@ public class PackageManagerBackupAgent extends BackupAgent {
return set;
}
// Util: write a set of names into a new state file
// Util: write out our new backup state file
private void writeStateFile(List<ApplicationInfo> apps, ParcelFileDescriptor stateFile) {
FileOutputStream outstream = new FileOutputStream(stateFile.getFileDescriptor());
DataOutputStream out = new DataOutputStream(outstream);
for (ApplicationInfo app : apps) {
try {
try {
// by the time we get here we know we've stored the global metadata record
byte[] metaNameBuf = GLOBAL_METADATA_KEY.getBytes();
out.writeInt(metaNameBuf.length);
out.write(metaNameBuf);
// now write all the app names too
for (ApplicationInfo app : apps) {
byte[] pkgNameBuf = app.packageName.getBytes();
out.writeInt(pkgNameBuf.length);
out.write(pkgNameBuf);
} catch (IOException e) {
Log.e(TAG, "Unable to write package manager state file!");
return;
}
} catch (IOException e) {
Log.e(TAG, "Unable to write package manager state file!");
return;
}
}
}