Android 4.4.2 encrypted backup problem (Illegal key size)

[vplugaru]

Hello,

I'm trying to unpack an Android 4.4.2 encrypted archive generated on a 2012 Nexus 7, and it's failing with the following message:

  Magic: ANDROID BACKUP
  Version: 1
  Compressed: 1
  Algorithm: AES-256
  Exception in thread "main" java.lang.RuntimeException: java.security.InvalidKeyException: Illegal key size
      at org.nick.abe.AndroidBackup.extractAsTar(AndroidBackup.java:192)
      at org.nick.abe.Main.main(Main.java:35)
  Caused by: java.security.InvalidKeyException: Illegal key size
      at javax.crypto.Cipher.checkCryptoPerm(Cipher.java:1024)
      at javax.crypto.Cipher.implInit(Cipher.java:790)
      at javax.crypto.Cipher.chooseProvider(Cipher.java:849)
      at javax.crypto.Cipher.init(Cipher.java:1348)
      at javax.crypto.Cipher.init(Cipher.java:1282)
      at org.nick.abe.AndroidBackup.extractAsTar(AndroidBackup.java:108)
      ... 1 more

The security password was 5-digit PIN-based, perhaps this is an issue?
Thank you for looking into it!

Best regards,
Valentin Plugaru

[nelenkov]

You need to install the unlimited strength JCE extensions. See the blog post for details:
http://nelenkov.blogspot.jp/2012/06/unpacking-android-backups.html

Length of the PIN/password is not related.

[vplugaru]

Dear Nikolay,

Thank you very much for the ultrafast response , and for the very useful ABE tool.
Indeed, using these policy files I am now able to unpack the backup file.

Best regards,
Valentin

[plaurits]

Hi!
I have issue as mentioned above even after loading the two jar files mentioned. Running jdk 1.8.0_25
Any ideas?
br Peter

[plaurits]

have started new thread instead,hence let's follow that only