EFFICIENT AUTHENTICATION FOR MOBILE AND PERVASIVE COMPUTING

• US 20130145169A1
• Filed: 12/04/2012
• Published: 06/06/2013
• Est. Priority Date: 12/05/2011
• Status: Active Grant

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Poovendran, Radha, Alomair, Basel
• Granted Patent: US 9,166,793 B2
• Time in Patent Office: Days
• US Class Current: 713/181
• CPC Class Codes: H04L 2209/805 Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor
• CPC Class Codes: H04L 9/0643 Hash functions, e.g. MD5, SHA, HMAC or f9 MAC
• CPC Class Codes: H04L 9/3242 involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC

Abstract

A method and system for authenticating messages is provided. A message authentication system generates an encrypted message by encrypting with a key a combination of a message and a nonce. The message authentication system generates a message authentication code based on a combination of the message and the nonce modulo a divisor. To decrypt and authenticate the message, the message authentication system generates a decrypted message by decrypting with the key the encrypted message and extracts the message and the nonce. The message authentication system then regenerates a message authentication code based on a combination of the extracted message and the extracted nonce modulo the divisor. The message authentication system then determines whether the regenerated message authentication code matches the original message authentication code. If the codes match, then the integrity and authenticity of the message are verified.

Claims

1. A method performed by a computing device to provide authentication for a message, the method comprising:

generating an encrypted message by encrypting with an encryption key an encryption combination of the message and a nonce; and

generating an authentication code based on a result of an authentication combination of the message and the nonce modulo a divisor.

2. The method of claim 1 wherein the encryption combination of the message and the nonce is a concatenation of the message and the nonce.

3. The method of claim 2 wherein the authentication combination of the message and the nonce is an addition of the nonce to the message multiplied by an authentication key.

4. The method of claim 3 wherein the divisor is a prime number.

5. The method of claim 1 wherein the authentication combination of the message and the nonce is an addition of the nonce to the message multiplied by an authentication key.

6. The method of claim 5 wherein the divisor is a prime number.

7. A method performed by a computing device to provide authentication for a message, the method comprising:

generating an encrypted message by encrypting with a key an encryption combination of the message and a nonce, the encrypting being based on a block cipher; and

generating an authentication code based on a result of an authentication combination of the message and the nonce modulo a divisor.

8. The method of claim 7 wherein the encryption combination of the message and the nonce is a concatenation of the message and the nonce that is encrypted as a block.

9. The method of claim 8 wherein the authentication combination is a sum of the message and the nonce modulo a power of two.

10. The method of claim 7 wherein the authentication combination is a sum of the message and the nonce modulo a power of two.

11. The method of claim 7 wherein the encrypting is based on cipher-block chaining.

12. The method of claim 11 wherein the encryption combination includes an encrypted nonce part based on encrypting with the key an exclusive OR of an initialization vector and a nonce.

13. The method of claim 12 wherein the encryption combination includes an encrypted message part based on encrypting with the key an exclusive OR of the encrypted nonce part and the message.

14. The method of claim 13 wherein the encrypted message includes the initialization vector, the encrypted nonce part, and the encrypted message part.

15. The method of claim 14 wherein the authentication combination is a sum of the message and the nonce modulo a power of two.

16. The method of claim 13 wherein the authentication combination is a sum of the message and the nonce modulo a power of two.

17. The method of claim 11 wherein the authentication combination is a sum of the message and the nonce modulo a power of two.

18. A computer-readable storage medium storing computer-executable instructions for controlling a device to generate an authentication code for a message, the instructions comprising:

instructions that generate an encrypted message by encrypting with an encryption key a concatenation of the message and a nonce; and

instructions that generate an authentication code by generating a dividend by multiplying the message by an authentication key and adding the nonce and setting the authentication code to the dividend modulo a divisor that is a prime number.

19. A computer-readable storage medium storing computer-executable instructions for controlling a device to generate an authentication code for a message, the instructions comprising:

instructions that generate an encrypted message using a key as a concatenation of an initialization vector, an encrypted nonce part, and an encrypted message part, the encrypted message being encrypted with a block cipher; and

instructions that generate an authentication code by generating a dividend by adding the message and a nonce and setting the authentication code to the dividend modulo a divisor that is a power of two.

20. The computer-readable storage medium of claim 19 wherein the block cipher is based on cipher-block chaining.