9 Commits

Author SHA1 Message Date
Matthew Williams
303650c9cd Add full backup criteria to android manifest
BUG: 20010079
Api change: ApplicationInfo now has a fullBackupContent int
where -1 is (off) 0 is (on) and >0 indicates an xml
resource that should be parsed in order for a developer
to indicate exactly which files they want to include/exclude
from the backup set.
dd: https://docs.google.com/document/d/1dnNctwhWOI-_qtZ7I3iNRtrbShmERj2GFTzwV4xXtOk/edit#heading=h.wcfw1q2pbmae

Change-Id: I90273dc0aef5e9a3230c6b074a45e8f5409ed5ce
2015-05-03 16:19:27 -07:00
Christopher Tate
11ae768cf1 Add payload-size preflight stage to full transport backup
We now peform a total-size preflight pass before committing data to the
wire.  This is to eliminate the large superfluous network traffic that
would otherwise happen if the transport enforces internal quotas: we
now instead ask the transport up front whether it's prepared to accept
a given payload size for the package.

From the app's perspective this preflight operation is indistinguishable
from a full-data backup pass.  If the app has provided its own full-data
handling in a subclassed backup agent, their usual file-providing code
path will be executed.  However, the files named for backup during this
pass are not opened and read; just measured for their total size.  As
far as component lifecycles, this measurement pass is simply another
call to the agent, immediately after it is bound, with identical
timeout semantics to the existing full-data backup invocation.

Once the app's file set has been measured the preflight operation
invokes a new method on BackupTransport, called checkFullBackupSize().
This method is called after performFullBackup() (which applies any
overall whitelist/blacklist policy) but before any data is delivered
to the transport via sendBackupData().  The return code from
checkFullBackupSize() is similar to the other transport methods:
TRANSPORT_OK to permit the full backup to proceed; or
TRANSPORT_REJECT_PACKAGE to indicate that the requested payload is
unacceptable; or TRANSPORT_ERROR to report a more serious overall
transport-level problem that prevents a full-data backup operation
from occurring right now.

The estimated payload currently does not include the size of the
source-package metadata (technically, the manifest entry in its
archive payload) or the size of any widget metadata associated with
the package's install.  In practice this means the preflighted size
underestimates by 3 to 5 KB.  In addition, the preflight API currently
cannot distinguish between payload sizes larger than 2 gigabytes;
any payload estimate larger than that is passed as Integer.MAX_VALUE
to the checkFullBackupSize() query.

Bug 19846750

Change-Id: I44498201e2d4b07482dcb3ca8fa6935dddc467ca
2015-03-26 18:57:36 -07:00
Jeff Sharkey
7f392defcc Catch a few extra users of UserEnvironment.
Change-Id: I3112773b72c329893e4118ef1c4f4087d899139e
2013-08-11 17:42:17 -07:00
Christopher Tate
ccbf84f44c Some system apps are more system than others
"signatureOrSystem" permissions are no longer available to all apps
residing en the /system partition.  Instead, there is a new /system/priv-app
directory, and only apps whose APKs are in that directory are allowed
to use signatureOrSystem permissions without sharing the platform cert.
This will reduce the surface area for possible exploits of system-
bundled applications to try to gain access to permission-guarded
operations.

The ApplicationInfo.FLAG_SYSTEM flag continues to mean what it is
says in the documentation: it indicates that the application apk was
bundled on the /system partition.  A new hidden flag FLAG_PRIVILEGED
has been introduced that reflects the actual right to access these
permissions.

At some point the "system" permission category will be
renamed to "privileged".

Bug 8765951

Change-Id: I6f0fd9cdb9170e076dfc66d83ecea76f8dd7335d
2013-06-17 12:47:35 -07:00
Christopher Tate
46cc43c6fa Full backup/restore now handles OBBs sensibly
OBB backup/ restore is no longer handled within the target app
process.  This is done to avoid having to require that OBB-using
apps have full read/write permission for external storage.

The new OBB backup service is a new component running in the
same app as the already-existing shared storage backup agent.
The backup infrastructure delegates backup/restore of apps'
OBB contents to this component (because the system process
may not itself read/write external storage).

From the command line, OBB backup is enabled by using new
-obb / -noobb flags with adb backup.  The default is noobb.

Finally, a couple of nit fixes:

- buffer-size mismatch between the writer and reader of chunked
  file data has been corrected; now the reading side won't be
  issuing an extra pipe read per chunk.

- bu now explicitly closes the transport socket fd after
  adopting it. This was benign but triggered a logged
  warning about leaked fds.

Bug: 6718844
Change-Id: Ie252494e2327e9ab97cf9ed87c298410a8618492
2013-03-07 13:47:20 -08:00
Christopher Tate
416c39e8d4 Full backup now saves getExternalFilesDir() content with the app data
... instead of only saving it with the enormous "shared storage" generic
data blob.  In parallel, we no longer store managed app-specific files
on external storage as part of the generic shared-storage blob.

At restore time we just go ahead and apply such files, though,
because they're a priori going to be part of an archive generated by
an older version of the platform, so that's how the data is expected
to be handled in those circumstances.

Bug 6718844

Change-Id: I4410514d368b11d74b3afe6b92d363d4115a3415
2013-02-14 18:46:53 -08:00
Christopher Tate
fb2ea43112 Fix full backup of shared storage
The manifest said android:allowBackup="false" for vestigal reasons;
originally, the incremental and full backup agents were separate, and
it was not possible to opt out of full backup.  When that got fixed,
unfortunately this one manifest was not corrected to the new regime.

Bug 5411789

Change-Id: Iafc8f1fdefc312dff59454485604b6c5c400f469
2011-10-18 15:47:59 -07:00
Christopher Tate
79ec80db70 Make full backup API available to apps
New methods for full backup/restore have been added to BackupAgent
(still hidden): onFullBackup() and onRestoreFile().  The former is the
entry point for a full app backup to adb/socket/etc: the app then writes
all of its files, entire, to the output.  During restore, the latter
new callback is invoked, once for each file being restored.

The full backup/restore interface does not use the previously-defined
BackupDataInput / BackupDataOutput classes, because those classes
provide an API designed for incremental key/value data structuring.
Instead, a new FullBackupDataOutput class has been introduced, through
which we restrict apps' abilities to write data during a full backup
operation to *only* writing entire on-disk files via a new BackupAgent
method called fullBackupFile().

"FullBackupAgent" exists now solely as a concrete shell class that
can be instantiated in the case of apps that do not have their own
BackupAgent implementations.

Along with the API change, responsibility for backing up the .apk
file and OBB container has been moved into the framework rather than
have the application side of the transaction do it.

Change-Id: I12849b06b1a6e4c44d080587c1e9828a52b70dae
2011-07-06 14:40:32 -07:00
Christopher Tate
b0628bfd5a Implement shared-storage full backup/restore
Every available shared-storage volume is backed up, tagged with its
ordinal in the set of mounted shared volumes.  This is an approximation
of "internal + the external card".  This lets us restore things to the
same volume [or "equivalent" volume, in the case of a cross-model
restore] as they originated on.

Also fixed a bug in the handling of files/dirs with spaces in
their names.

Change-Id: I380019da8d0bb5b3699bd7c11eeff621a88e78c3
2011-06-07 12:16:27 -07:00