Originally Posted by Renate NST

Well, you seem to have a handle on all this.
I've never heard of pkcs7 or any of its friends.

You try it once, next time you know it all. Just in case, it’s all here: http://www.openssl.org/docs/apps/openssl.html

Originally Posted by Renate NST

Deleting packages.xml will result in the non-shared user ids to be assigned in order as the APKs are discovered by the PackageManager.

I.e. it won’t work in the case I mentioned?
Or it does check /data/data to see if a user was assigned already and reassigns it?
I guess, I should try it on emulator...

Originally Posted by Renate NST

User ids are only used for file permissions on /data/data as far as I know.

And /data/dalvik-cache too:
ls -l /data/dalvik-cache/*apk*

BTW: Some permissions are assigned in /system/etc/permissions/platform.xml, but for uid only.
dumpsys package shows some gids too,
I was wondering where are uid assigned to gids and can we use them too?

---------- Post added at 04:01 AM ---------- Previous post was at 03:48 AM ----------

Originally Posted by ApokrifX

I.e. it won’t work in the case I mentioned?
Or it does check /data/data to see if a user was assigned already and reassigns it?

Oops... Apparently, well known BugOrFeature: http://forum.xda-developers.com/showthread.php?t=522935

From packages.xml

UserID	CertIndex
1000	13	com.google.android.providers.subscribedfeeds	/system/app/GoogleSubscribedFeedsProvider.apk	
1000	13	com.google.android.server.checkin	/system/app/GoogleCheckin.apk	
1000	4	android	/system/framework/framework-res.apk	
1000	4	com.android.providers.settings	/system/app/SettingsProvider.apk	
1000	4	com.android.providers.subscribedfeeds	/system/app/AccountAndSyncSettings.apk	
1000	4	com.android.settings	/system/app/Settings.apk	
1000	4	com.bn.app.crypto.server	/system/app/CryptoServer.apk	
1000	4	com.bn.authentication.svc	/system/app/BnAuthenticationService.apk	
1000	4	com.bn.demomode	/system/app/DemoMode.apk	
1000	4	com.bn.devicemanager	/system/app/DeviceManager.apk	
1000	4	com.bn.nook.quickstart	/system/app/QuickStartActivity.apk	
1000	4	com.bn.syschecksum	/system/app/SysChecksum.apk	
1000	4	com.bn.waveformdownloader.svc	/system/app/WaveformDownloader.apk

Apparently, (1000, 13) and (1000, 4) should be two different uses, right?
But according to "dumpsys package" output, they are same:

SharedUser [android.uid.system] (49e7f2a0):
    userId=1000 gids=[1015, 3003, 3002, 3001, 1007]

  Package [com.google.android.providers.subscribedfeeds] (49ee7390):
    userId=1000 gids=[]
    sharedUser=SharedUserSetting{49e7f2a0 android.uid.system/1000}
    pkg=Package{49f73f88 com.google.android.providers.subscribedfeeds}
    codePath=/system/app/GoogleSubscribedFeedsProvider.apk
    resourcePath=/system/app/GoogleSubscribedFeedsProvider.apk
    dataDir=/data/data/com.google.android.providers.subscribedfeeds
    targetSdk=7
    supportsScreens=[medium, large, small, resizeable, anyDensity]
    timeStamp=1292347460000
    signatures=PackageSignatures{49e403a0 [49eb4fd8]}
    permissionsFixed=false pkgFlags=0x1 installStatus=1 enabled=0

  Package [com.android.settings] (49ee50f8):
    userId=1000 gids=[]
    sharedUser=SharedUserSetting{49e7f2a0 android.uid.system/1000}
    pkg=Package{49eff728 com.android.settings}
    codePath=/system/app/Settings.apk
    resourcePath=/system/app/Settings.apk
    dataDir=/data/data/com.android.settings
    targetSdk=7
    supportsScreens=[medium, large, small, resizeable, anyDensity]
    timeStamp=1217592000000
    signatures=PackageSignatures{49ea84c8 [49ed6f38]}
    permissionsFixed=false pkgFlags=0x1 installStatus=1 enabled=0

# ls -l /data/data/com.google.android.providers.subscribedfeeds
drwxr-xr-x system   system            2012-01-22 17:34 lib
drwxrwx--x system   system            2012-07-01 00:03 databases
drwxrwx--x system   system            2012-01-22 20:00 files
drwxrwx--x system   system            2012-07-01 00:03 shared_prefs

# ls -l /data/data/com.android.settings
drwxr-xr-x system   system            2000-01-01 02:28 lib
drwxrwx--x system   system            2011-06-18 20:55 cache
drwxrwx--x system   system            2011-06-18 20:55 databases
drwx------ system   system            2012-01-22 17:46 files
drwxrwx--x system   system            2012-01-22 21:01 shared_prefs