Radiotelephone controller configured for coresident secure and nonsecure modes

• US 5,060,264 A
• Filed: 01/05/1990
• Issued: 10/22/1991
• Est. Priority Date: 01/05/1990
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Cashen, Dennis, Marry, Patrick J., Muellner, Grazyna E., Ford, David K., Pini, Rafaele
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): Cain, David
• Application Number:
  US07/461,570
• Time in Patent Office: 655 Days
• Field of Search: 380/46, 380/23, 380/33
• US Class Current: 380/46
• CPC Class Codes: G06F 21/74 operating in dual or compartmented mode, i.e. at least one secure mode
• CPC Class Codes: H04W 12/04 Key management, e.g. using generic bootstrapping architecture [GBA]
• CPC Class Codes: H04W 12/086 using security domains
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A controller for a radiotelephone having the capability of operation in both a secure mode for call authorization and a nonsecure mode for user interface is disclosed. The nonsecure mode and secure mode of operation are both resident in a single microcontroller which runs the nonsecure operations until a requirement for the secure operation is requested during call placement. The nonsecure mode is disabled during the period of time the secure mode is operational and is reenabled upon completion of the secure mode operation. The secure mode cannot be accessed externally to the microcontroller.

Claims

1. A controller for a radiotelephone apparatus which communicates with a fixed site, the controller having an internal secure mode of operation and an internal nonsecure mode of operation, comprising:

means for inputting a message received from the fixed site;

means, responsive to said message, for calculating a signed response from a stored numerical subscriber authentication key, such that said numerical subscriber authorization key and said calculations cannot be accessed external to the controller;

means for communicating with a radiotelepone apparatus user interface device external to the controller; and

means for enabling said means for calculating and for disabling said means for communicating when said means for calculating is enabled.

2. A controller for a radiotelephone apparatus in accordance with claim 1 wherein said means for enabling further comprises means for determining a requirement for said signed response calculation.

3. A radiotelephone apparatus which generates and transmits a signed response when making a radiotelephone call, the signed response calculated from a random number and a subscriber authorization key and in which both the subscriber authorization key and the calculation is performed in a secure fashion in a controller, the radiotelephone apparatus comprising:

means in the controller for storing the numerical subscriber authentication key and for calculating the signed response therefrom, such that the numerical subscriber authorization key and the calculations cannot be accessed external to the controller;

means for communicating in a nonsecure manner with a keypad external to the controller whereby key depressions may be detected;

means for determining a requirement for said signed response calculation; and

means for enabling said means for storing and calculating and for disabling said means for communicating when said means for storing and calculating is enabled.

4. A method of generating a signed response when making a radiotelephone call in a radiotelephone apparatus, the signed response calculated from a random number and a stored subscriber authorization key and in which both the subscriber authorization key and the calculation is performed in a secure fashion in a radiotelephone apparatus controller, the method comprising:

calculating the signed response from the stored subscriber authentication key, such that the numerical subscriber authorization key and the calculations cannot be accessed eternal to the controller;

communicating in a nonsecure manner with a keypad external to the controller whereby key depressions may be detected;

determining a requirement for said signed response calculation; and

enabling said calculating step and disabling said communicating step.

5. A controller for a radiotelephone apparatus, the controller internally sharing processing modes, comprising:

means for receiving an input from a radiotelephone apparatus user interface device external to the controller;

means for processing said input in a nonsecure mode;

means for detecting a requirement for a secure processing mode;

means for disabling reception of said input;

means for calculating a signed response from a numerical subscriber authentication key in a secure processing mode; and

means for reenabling said disabled input reception.

6. A method of sharing internal processing modes in a controller for a radiotelephone apparatus, comprising the steps of:

receiving an input from a radiotelephone apparatus user interface device external to the controller;

processing said input in a nonsecure mode;

detecting a requirement for a secure processing mode;

disabling reception of said input;

calculating a signed response from a numerical subscriber authentication key in a secure processing mode; and

reenabling said disabled input reception.

7. A microcontroller for a radiotelephone apparatus, the microcontroller internally sharing processing modes, comprising:

means for receiving user information from a radiotelephone apparatus user interface device external to the microcontroller;

means for processing received user information in a nonsecure processing mode;

means for detecting a requirement for a secure processing mode;

means for disabling reception of said user information in response to said detected requirement;

means for receiving service request information and calculating a signed response from a stored subscriber authorization key in a secure processing mode internal to the microcontroller;

means for transmitting said calculated signed response; and

means for reenabling said disabled reception of said user information.

8. A method of sharing processing modes in a microcontroller for a radiotelephone apparatus, the method comprising the steps of:

receiving user information from a radiotelephone apparatus user interface device external to the microcontroller;

processing said received information in a nonsecure processing mode;

detecting a requirement for a secure processing mode;

disabling reception of said user information in response to said detecting step;

receiving service request information and calculating a signed response from a stored subscriber authorization key in a secure processing mode internal to the microcontroller;

transmitting said calculated signed response; and

reenabling said disabled reception of said user information.