Resetting a device password when content protection is turned on
If you or a BlackBerry® device user turns on content protection for a BlackBerry device that is running BlackBerry® Device Software version 4.3 or later, you can reset the device password using a BlackBerry® Enterprise Server version 4.1 SP5 or later. The BlackBerry® Enterprise Solution uses the remote password reset cryptographic protocol to reset the device password when content protection is turned on. The device does not prompt the user for the old device password.
- permit the device to encrypt the content protection key again with the new password, without the old password being available
- prevent a hardware-based attack on the device from recovering the content protection key without knowing either the device password or the IT policy private key that the BlackBerry Enterprise Server generates for the device
- prevent the BlackBerry Enterprise Server from accessing any data that a potentially malicious user could use to recover the content protection key
To reset the device password, you send the Specify new device password and lock device IT administration command to the device. You should send the IT administration command to a content-protected device that is in the possession of the user only. If you send the IT administration command to a device that is in the possession of a potentially malicious user, that user can use a hardware-based attack to recover the key pair that the device created when it received the IT policy. The potentially malicious user can use the key pair to decrypt all the data on the device.
Process flow: Resetting a device password when content protection is turned on
The process flow is designed so that the BlackBerry® Enterprise Server cannot reconstruct the encryption key at a later time.
The BlackBerry Enterprise Server performs the following actions when you send the Specify new device password and lock device IT administration command to a BlackBerry device when content protection is turned on:
- generates an encryption key using the IT policy public key and the NIST recommended 521-bit elliptic curve over a prime field
- encrypts the content protection key using the encryption key and the new device password (which is also encrypted)
- sends the data required to reconstruct the encryption key to the device
Cryptosystem parameters that the remote password reset cryptographic protocol uses
Uppercase parameters represent elliptic curve points. Lowercase parameters represent scalars. The elliptic curve group operations are additive.