Apparatus and method for secure field upgradability with unpredictable ciphertext

• US 7,634,665 B2
• Filed: 10/11/2006
• Issued: 12/15/2009
• Est. Priority Date: 10/29/1999
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Johnson, Anders
• Primary Examiner(s): Pich; Ponnoreay
• Application Number:
  US11/545,446
• Publication Number:
  US 20080040617A1
• Time in Patent Office: 1,161 Days
• Field of Search: 713/189
• US Class Current: 713/189
• CPC Class Codes: H04L 2209/12 Details relating to cryptographic hardware or logic circuitry
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 9/0662 with particular pseudorandom sequence generator

Abstract

An apparatus and method for enabling functionality of a component, wherein the apparatus includes a random number generating module for generating a random number, and a hash function module in communication with the random number generating module. A host is provided in communication with the random number generating module, and at least one memory in communication with the host is included. An encryption module in communication with the at least one memory is provided, and a comparing device in communication with the encryption module and the hash function module is included. The comparing device of the apparatus compares a first bit string to a second bit string to generate a function enable output for the component.

Claims

1. An apparatus for enabling functionality of a component, said apparatus comprising:

a random number generating module configured to generate a random number;

a hash function module in communication with said random number generating module;

a host in communication with said random number generating module, said host being configured to receive a guess passcode from a manufacturer of the component;

at least one memory in communication with said host;

an encryption module in communication with said at least one memory; and

a comparing device in communication with said encryption module and said hash function module,

wherein said at least one memory further comprises a public key module in communication with said encryption module, said public key module being configured to store a public key therein,

wherein said comparing device is configured to compare a ciphertext bit string generated by the encryption module to a hash value generated by the hash function module to generate a function enable output to the component, which enables functionality of the component.

2. The apparatus for enabling functionality of a component as recited in claim 1, wherein said hash function module further comprises a one-way hash function module configured to receive a pre-image input and output a hash value using a one-way hash function algorithm.

3. The apparatus for enabling functionality of a component as recited in claim 1, wherein said encryption module further comprises a public key encryption module, said public key encryption module being configured to receive a public key and a guess passcode from said at least one memory as inputs and generate a ciphertext bit string as an output.

4. The apparatus for enabling functionality of a component as recited in claim 1, wherein said random number generating module further comprises:

a NAND gate in communication with said linear feedback shift register; and

at least one inverter in communication with said linear feedback shift register and said NAND gate,

wherein said NAND gate is configured to receive an activation pulse.

5. The apparatus for enabling functionality of a component as recited in claim 1, wherein said apparatus further comprises a selecting device configured to select at least one of the function enable output and a bonding option output.

6. The apparatus for enabling functionality of a component as recited in claim 5, wherein said selecting device further comprises an OR gate having at least one input configured to receive the function enable output and the bonding option output.

7. The apparatus for enabling functionality of a component as recited in claim 6, said apparatus further comprising a bonding option circuit, said bonding option circuit comprising:

a pull up resistor in communication with said OR gate and a power supply; and

a switch in communication with a ground potential and said OR gate.

8. The apparatus for enabling functionality of a component as recited in claim 5, wherein said selecting device further comprises:

a multiplexer having at least one multiplexer input in communication with the comparing device and a multiplexer output;

a selection circuit in communication with the at least one multiplexer input;

a bonding option circuit in communication with the at least one multiplexer input,

wherein said multiplexer is configured to receive a selection input from the selection circuit that is used to determine whether to enable functionality of said component in accordance with the bonding option output or the function enable output.

9. The apparatus for enabling functionality of a component as recited in claim 8, wherein said selection circuit further comprises:

at least one first non-volatile memory location having at least one first selection bit stored therein;

at least one second non-volatile memory location having at least one second selection bit stored therein; and

an OR gate having a first input, a second inverted input, and a logic output, said first input being in communication with said at least one first nonvolatile memory location and said second inverted input being in communication with said at least one second non-volatile memory location,

wherein said selection circuit is configured to generate a selection indicator on the logic output of the OR gate in accordance with the at least one first selection bit and said at least one second selection bit.

10. The apparatus for enabling functionality of a component as recited in claim 1, wherein said comparing device further comprises a comparator.

11. The apparatus for enabling functionality of a component as recited in claim 1, wherein said component further comprises at least one of a network switch and a media access controller.