Pseudorandom composition-based cryptographic authentication process

• US 5,619,575 A
• Filed: 08/22/1994
• Issued: 04/08/1997
• Est. Priority Date: 08/22/1994
• Status: Expired due to Term

• Current Assignee: Lear Corporation Eeds & Interiors (Rtx Corporation)
• Original Assignee: United Technologies Automotive, Inc. (Lear Corporation)
• Inventors: Finn, Alan M., Koopman, Philip J. Jr., LaBarre, Robert E.
• Primary Examiner(s): Cain, David C.
• Application Number:
  US08/294,147
• Time in Patent Office: 960 Days
• Field of Search: 380/28, 380/42, 380/4, 380/49
• US Class Current: 380/28
• CPC Class Codes: H04L 2209/04 Masking or blinding
• CPC Class Codes: H04L 2209/805 Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor
• CPC Class Codes: H04L 2209/84 Vehicles
• CPC Class Codes: H04L 9/002 Countermeasures against attacks on cryptographic mechanisms network architectures or network communication protocols for protection against malicious traffic H04L63/1441
• CPC Class Codes: H04L 9/0662 with particular pseudorandom sequence generator
• CPC Class Codes: H04L 9/3271 using challenge-response

Abstract

The pseudorandom process iteratively applies a selected CRC encryption process on the information to be encrypted. The encryption process is selected by testing one of the digits comprising the number to be encrypted. A first encryption process is used if the tested digit is a 1; a second encryption process is used if the tested digit is a 0. The process is repeated a plurality of times, e.g. once for each digit in the number to be encrypted, resulting in a highly encrypted value that is not easily reverse engineered by chosen or known plaintext attack.

Claims

1. A method of encrypting digital information comprising the steps of:

(a) representing said digital information as a set of binary digits, N;

(b) testing one of the binary digits to determine if the digit is a 1 or a 0;

(c) applying a first encryption process on said digital information if the digit is a 1 or a second encryption process on said digital information if the digit is a 0 to produce an altered set of digital information;

(d) replacing said digital information with said altered set of digital information;

(e) repeating steps (b) through (d) upon testing a second of said binary digits to determine if said second of said binary digits is a 1 or a 0.

2. The method of claim 1, wherein said first encryption process comprises an enhanced CRC process.

3. The method of claim 1, wherein said second encryption process comprises an enhanced CRC process.

4. The method of claim 1, further comprising the step of performing a third encryption process on said set of binary digits prior to said step of testing one of the binary digits.

5. The method of claim 1, wherein said step (e) is performed iteratively over each digit in said set of digits.

6. The method of claim 1, wherein a plurality of binary digits are tested in step (a).

7. The method of claim 4, wherein said third encryption process comprises an enhanced CRC process.

8. A method of encrypting digital information represented by a plurality of binary digits, said method comprising the steps of:

(a) testing a first bit of the plurality of binary digits to determine if the digit is a "1" or a "0";

(b) encrypting the digital information according to a first encryption process if the digit is a "1" or according to a second encryption process if the digit is a "0" to produce an altered set of digital information;

(c) replacing the digital information with said altered set of digital information; and

(d) repeating said steps (a) through (c) upon testing a second one of said binary digits to determine if the digit of said second one of said binary digits is a "1" or a "0".

9. The method of claim 8, wherein said first encryption process comprises an enhanced CRC process.

10. The method of claim 8, wherein said second encryption process comprises an enhanced CRC process.

11. The method of claim 8, further comprising the step of:

performing a third encryption process on the plurality of binary digits prior to said step of testing a first bit of the plurality of binary digits.

12. The method of claim 11, wherein said third encryption process comprises an enhanced CRC process.

13. The method of claim 8, wherein the plurality of binary digits comprises at least three bits, and said step (d) is performed iteratively over each bit of the plurality of binary digits.

14. The method of claim 8, wherein a number of binary digits are tested in step (a).

15. A pseudorandom composition based cryptographic authentication process for encrypting digital information represented as a plurality of binary digits, said pseudorandom composition based cryptographic authentication process comprising the steps of:

(a) testing a first bit of the binary digits to determine if the digit is a 1 or a 0;

(b) encrypting the digital information according to a first encryption process if the digit is a 1 or according to a second encryption process if the digit is a 0 to produce an altered set of digital information, said first and second encryption process comprising an enhanced CRC process;

(c) replacing the digital information with said altered set of digital information; and

(d) repeating said steps (a) through (c) upon testing a second one of said binary digits to determine if the digit of said second one of said binary digits is a 1 or a 0.

16. The method of claim 15, further comprising the step of:

performing a third encryption process on said set of binary digits prior to said step of testing a first bit of the binary digits.

17. The method of claim 16, wherein said third encryption process comprises an enhanced CRC process.

18. The method of claim 15, wherein the plurality of binary digits comprises at least three bits, and said step (d) is performed iteratively over each bit of the plurality of binary digits.

19. The method of claim 15, wherein a number of binary digits are tested in step (a).