Method and apparatus for true random number generation within cryptographic hardware

Patent metadata

Field	Value
Publication number	US-12375271-B2
Application number	US-202118042412-A
Country	US
Kind code	B2
Filing date	Aug 13, 2021
Priority date	Aug 21, 2020
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

A method of generating true random numbers for use by a cryptographic hardware component for cryptographic algorithms or communication protocols, and a cryptographic hardware component for cryptographic algorithms or communication protocols. The method comprises the steps of controlling a clock pulsewidth, PW, for pulsed-latch clocking in the cryptographic hardware component to switch between using the cryptographic hardware component to generate the true random numbers in a first operating state; and using the cryptographic hardware component for cryptographic processing in a second operating state.

First claim

The invention claimed is:

1. A method of generating true random numbers for use by a cryptographic hardware component for cryptographic algorithms or communication protocols, the method comprising the steps of:
controlling a clock pulsewidth, PW, for pulsed-latch clocking in the cryptographic hardware component to switch between using the cryptographic hardware component to generate the true random numbers in a first operating state; and
using the cryptographic hardware component for cryptographic processing other than generating true random numbers in a second operating state.

2. The method of claim 1 , wherein using the cryptographic hardware component to generate the true random numbers in the first operating state comprises exploiting hold-margin in pulsed latch pipelines of the cryptographic hardware component via clock pulsewidth overstretching.

3. The method of claim 1 , wherein controlling the PW comprises controlling the PW to be smaller than a hold violation window in the cryptographic hardware component during the second operating state.

4. The method of claim 1 , wherein controlling the PW comprises controlling the PW to be larger than the hold violation window in the cryptographic hardware component during the first operating state.

5. The method of claim 4 , wherein controlling the PW comprises controlling the PW to be larger than the hold violation window and larger than a minimum loop delay in the cryptographic hardware component during the first operating state.

6. The method of claim 5 , wherein controlling the PW comprises controlling the PW to be larger than a threshold multiple of the minimum loop delay in the cryptographic hardware component during the first operating state.

7. The method of claim 5 , wherein the threshold multiple comprises a nominal clock pulsewidth plus a hold margin to increase the combinational min-delay.

8. The method of claim 4 , wherein PW is controlled to be any value greater than 32 F01, wherein F01 is an inverter delay with a fan-out of one for a given design technology.

9. The method of claim 8 , wherein PW is controlled to be 64 F01.

10. The method of claim 8 , wherein PW is controlled to be 256 F01.

11. A cryptographic hardware component for cryptographic algorithms or communication protocols, the cryptographic hardware component configured for controlling a clock pulsewidth, PW, for pulsed-latch clocking in the cryptographic hardware component to switch between using the cryptographic hardware component to generate true random numbers in a first operating state, and using the cryptographic hardware component for cryptographic processing other than generating true random numbers in a second operating state.

12. The cryptographic hardware component of claim 11 , configured for generating the true random numbers in the first operating state by exploiting hold-margin in pulsed latch pipelines of the cryptographic hardware component via clock pulsewidth overstretching.

13. The cryptographic hardware component of claim 11 , configured for controlling the PW to be smaller than a hold violation window in the cryptographic hardware component during the second operating state.

14. The cryptographic hardware component of claim 11 , configured for controlling the PW to be larger than the hold violation window in the cryptographic hardware component during the first operating state.

15. The cryptographic hardware component of claim 14 , configured for controlling the PW to be larger than the hold violation window and larger than the minimum loop delay in the cryptographic hardware component during the first operating state.

16. The cryptographic hardware component of claim 15 , configured for controlling the PW to be larger than the threshold multiple of the minimum loop delay in the cryptographic hardware component during the first operating state.

17. The cryptographic hardware component of claim 15 , wherein the threshold multiple comprises a nominal clock pulsewidth plus a hold margin to increase the combinational min-delay.

18. The cryptographic hardware component of claim 14 , wherein PW is controlled to be any value greater than 32 F01, wherein F01 is an inverter delay with a fan-out of one for a given design technology.

19. The cryptographic hardware component of claim 18 , wherein PW is controlled to be 64 F01.

20. The cryptographic hardware component of claim 18 , wherein PW is controlled to be 256 F01.

Assignees

• Nat Univ Singapore

Inventors

• Taneja Sachin
• Alioto Massimo

Classifications

• G06F7/588

  Random number generators, i.e. based on natural stochastic processes · CPC title

• G09C1/00

  Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system (cryptographic typewriters G09C3/00) · CPC title

• H04L9/0869 Primary

  involving random numbers or seeds · CPC title

• G06F1/08

  Clock generators with changeable or programmable clock frequency · CPC title

• G06F21/602 Primary

  Providing cryptographic facilities or services · CPC title