4 replies to this topic

[chriv]

This is my first post on MoDaCo, so forgive me if I'm out of place.

I am interested in locking down my Nexus One so that it is more secure, and so that it won't be seen as a rooted phone.  I'm running CyanogenMod-7.1.0-N1 (Android 2.3.7, baseband 32.41.00.30U_5.08.00.04, build number GWK74).  I'm also using ClockworkMod 5.0.2.0 as my recovery image.  The phone is a U.S. Nexus One (AT&T).

Here are my goals:

•   I don't want "adb shell" to return a "#" prompt (superuser).  I want it to give me a "{:content:}quot; prompt (regular user).  This is to make my phone more secure.  I would like to be prompted for a password if I try and run su.
•   I want to backup /system/xbin/su, so that is not easily found by programs like "Pocket Blu", "Flixster Movies", and "Google Videos."
•   I don't want Superuser.apk present or easily found by programs like "Pocket Blu", "Flixster Movies", and "Google Videos."

I don't mind having to use a filename other than su to enter a root prompt.  I don't mind having to remount /system and having to copy back su whenever I want to run a program like "Titanium Backup" or other programs that require root access.

• How do I make adb shell secure?  Do I have to replace my recovery image?  Do I have to replace my boot image?
• How do I password protect su when run from a terminal or adb shell?
• How do I prevent "Pocket Blu" from detecting root?
• How do I prevent Flixster "Movies" from detecting root?
• How do I prevent "Google Videos" from detecting root?

Any feedback is appreciated.  Moderators feel free to move this to the proper forum.

Thanks!

[Amphoras]

For the adb shell part, I think you might need a different boot.img, but I'm not sure about that.

As for preventing the apps from detecting root, you could try this app. I don't have any of those apps to try it with, so I don't know whether it will work or not. It also depends what on how the apps detect if you have root or not. To use it, first click the "Hide binary" button, and it will get rid of the su binary file. This means that nothing will be able to request root access, eg. Titanium Backup will act as though your phone it unrooted. To get it working again, click the "Restore binary" button. To remove the Superuser app, click the "Remove app" button. That should delete it from /system/app, and attempt to uninstall any updates from /data/app. You can replace it with the "Restore app" button. If that doesn't work for some reason, then you can just redownload it from the market.

To hide/restore the binary, the app needs to be there to give permissions, so the order to hide/restore should be:

*Hide binary
*Hide app
*Restore app
*Restore binary

If you hide/restore the app, it will probably delete the data as well, so you'll need to regrant permissions each time. It doesn't require one just now, but if you wanted I could make it need a password to restore the binary again.

Hopefully it will help, as I said I don't know how those apps detect root access, so it may or may not trick them.

[chriv]

Amphoras, on 10 December 2011 - 05:01 PM, said:

For the adb shell part, I think you might need a different boot.img, but I'm not sure about that.

Thanks.  Can anyone verify this (how to not have root at an adb shell prompt for CM7.1)?

Amphoras, on 10 December 2011 - 05:01 PM, said:

As for preventing the apps from detecting root, you could try this app. I don't have any of those apps to try it with, so I don't know whether it will work or not. It also depends what on how the apps detect if you have root or not. To use it, first click the "Hide binary" button, and it will get rid of the su binary file. This means that nothing will be able to request root access, eg. Titanium Backup will act as though your phone it unrooted. To get it working again, click the "Restore binary" button. To remove the Superuser app, click the "Remove app" button. That should delete it from /system/app, and attempt to uninstall any updates from /data/app. You can replace it with the "Restore app" button. If that doesn't work for some reason, then you can just redownload it from the market.

Thanks again.  Hide My Root is nice and thorough, but it was not clever enough to trick Google Videos.  I have tried to test it with Pocket Blu, but that app is so slow, that I don't know if it was able to hide root from it or not.  Last but not least, I have not tried this yet with Flixster Movies.

Does anyone know how these apps do their root detection?  Google Videos must be doing a really intrusive check, as both hiding the su binary and uninstalling the Superuser app are not enough to trick it.

Edit:  Hide My Root also fails to trick Flixster Movies.  It also fails to trick Pocket BLU. - Any ideas, anyone?

Edited by chriv, 12 December 2011 - 05:27 PM.

[Amphoras]

chriv, on 12 December 2011 - 04:48 PM, said:

Thanks.  Can anyone verify this (how to not have root at an adb shell prompt for CM7.1)?



Thanks again.  Hide My Root is nice and thorough, but it was not clever enough to trick Google Videos.  I have tried to test it with Pocket Blu, but that app is so slow, that I don't know if it was able to hide root from it or not.  Last but not least, I have not tried this yet with Flixster Movies.

Does anyone know how these apps do their root detection?  Google Videos must be doing a really intrusive check, as both hiding the su binary and uninstalling the Superuser app are not enough to trick it.

Edit:  Hide My Root also fails to trick Flixster Movies.  It also fails to trick Pocket BLU. - Any ideas, anyone?

I did some research, and it appears that Google Videos and Flixster Movies, as well as others, use some widevine software that detects this. The company that makes the software is owned by Google. Its not entirely clear what it checks for, so not sure how/if you could trick it. There are modified versions of these apps available though that skip the root check so apparently work on rooted phones.

[chriv]

Amphoras, on 12 December 2011 - 08:20 PM, said:

I did some research, and it appears that Google Videos and Flixster Movies, as well as others, use some widevine software that detects this. The company that makes the software is owned by Google. Its not entirely clear what it checks for, so not sure how/if you could trick it. There are modified versions of these apps available though that skip the root check so apparently work on rooted phones.

Just a quick note.  I'm less concerned about "unrooting" my AT&T Google Nexus One these days.  I've switched to the Verizon Samsung Galaxy Nexus (LTE/CDMA), rooted the stock ROM, and the newest version of OTA Rootkeeper from supercurio/Voodoo is working well for me for temp un-root.  It has allowed me to use Pocket Blu, Google Videos, and Flixster Movies.  It is OTA Rootkeeper v1.2, released 2012/01/10.