176 reputation
5
bio website nelenkov.blogspot.com
location Tokyo, Japan
age
visits member for 2 years, 5 months
seen Nov 20 at 2:44

Some (mostly Android-related code): https://github.com/nelenkov

Some Android apps: http://goo.gl/Nw72w

Book: http://www.nostarch.com/androidsecurity


Oct
10
awarded  Autobiographer
Aug
27
comment Is there a way to look inside and modify an adb backup created file?
Yeah, they packaged the tool (the Java one) I wrote:) I also helped port the thing to Perl. If you didn't read the READMEs, it might not be immediately apparent that the writeup came first, then the tools....
Jan
29
answered Hardware backed Credentials Storage on Galaxy Nexus
Jan
17
comment Hardware backed Credentials Storage on Galaxy Nexus
Reference: nelenkov.blogspot.com/2012/07/…. And, yes, TZ is not a TPM.
Jan
17
comment Hardware backed Credentials Storage on Galaxy Nexus
Actually the Galaxy Nexus has had a hardware-backed credential storage since 4.1. It just isn't enabled in production builds. Also, TrustZone is a software thing, it does not require anything but a TZ-enabled ARM chip, which pretty much all recent ones are. TPM requires an actual secure chips. In order to take advantage of TZ, a secure OS needs to be installed, along with the relevant drivers and a way to link it to Android. This requires the manufacturer to integrate it, of course.
Dec
24
awarded  Supporter
Oct
1
comment Is there a way to look inside and modify an adb backup created file?
That's just an example. Optimize accordingly for larger files. Also GUI editors and 2GB files don't mix well :)
Jun
25
comment Is there a way to look inside and modify an adb backup created file?
You can also try the Perl scripts linked in the entry. One of them attempts to fix broken archive.
Jun
25
revised Is there a way to look inside and modify an adb backup created file?
added 143 characters in body
Jun
20
comment Is there a way to look inside and modify an adb backup created file?
So, if you used a binary editor, and deleted the shared storage part (easily recognizable because you can see the file paths as strings), you should get a (somewhat) valid backup and maybe even manage to unpack it.
Jun
20
comment Is there a way to look inside and modify an adb backup created file?
As silly as it may sound, you need to specify -noshared, to get the shared storage backed up correctly. If you specify -shared, it won't be properly encrypted/compressed and you will get the ZipException.
Jun
20
comment Is there a way to look inside and modify an adb backup created file?
Now I am seeing the 'ZipException: invalid stored block lengths.' too. It seems that under some conditions the shared storage backup part is not compressed/encrypted, although the other part of the backup is (data and apks). Still not sure when exactly this happens. I somehow managed to produce working backups in my initial tests.
Jun
15
awarded  Commentator
Jun
15
comment Is there a way to look inside and modify an adb backup created file?
You could modify the extract program to output the deccrypted, but still compressed file and then try to find some tool or library that would decompress ignoring errors. Java's Deflater doesn't have such an option. Or you could try to use zlib directly. You could try 7Zip or use the zlib/jzlib.
Jun
14
comment Is there a way to look inside and modify an adb backup created file?
I've tested the tool with Galaxy Nexus and Nexus S, both running 4.0.4, so it should be compatible. If you are getting the same error when doing an 'adb restore', maybe the file is somehow corrupt?
Jun
11
comment Is there a way to look inside and modify an adb backup created file?
What Android version was your backup created with? Maybe there are some differences between versions. There are new bugs in 4.0.4, so there definitely have been some changes.
Jun
8
comment Is there a way to look inside and modify an adb backup created file?
Done. See wiki entry for some details and link to the unpack utility.
Jun
8
awarded  Editor
Jun
8
revised Is there a way to look inside and modify an adb backup created file?
added archive and encryption format details; added link to unpack utility code
Jun
5
comment Is there a way to look inside and modify an adb backup created file?
Cool, glad you got it working. If the decryption finished without an error, a simple tar xvf decrypted.bkp should do it. I put together a simple extractor class that does not require patching Bouncy Castle, will post it somewhere later.