RFID secure authentication

Patent metadata

Field	Value
Publication number	US-9489785-B2
Application number	US-201414189259-A
Country	US
Kind code	B2
Filing date	Feb 25, 2014
Priority date	Mar 14, 2013
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

Authentication systems and methods for a population of devices each associated with an RFID tag are described. For each device, a secret key is combined cryptographically with a publicly-readable unique identifier (UID) of an RFID tag to obtain a unique authorization signature. The RFID tag is prepared utilizing the unique authorization signature as memory-access and/or tag-operation password(s). The systems and methods may safeguard against attacks whereby compromise of a single tag will not compromise the entire population of devices and may reduce or eliminate the use of inappropriate surgical devices during a surgical procedure.

First claim

What is claimed is:

1. A method of authenticating an RFID tag, comprising: selecting a secret key;
preparing the RFID tag, wherein preparing the RFID tag comprises:
reading a unique identification code from the RFID tag;
creating an authentication signature by encrypting the secret key with the unique identification code; and
setting a password of the RFID tag to the authentication signature; and authenticating the RFID tag, wherein authenticating the RFID tag comprises:
reading the unique identification code from the RFID tag;
re-creating the authentication signature by encrypting the secret key with the unique identification code;
attempting to access a function of the RFID tag by providing the authentication signature to the RFID tag as the password; and
determining that the RFID tag is authentic if the attempt to access a function of the RFID tag is successful.

2. The method of authenticating an RFID tag in accordance with claim 1 , wherein creating an authentication signature comprises performing a hash function on the secret key and unique identification code (UID) to obtain the authentication signature.

3. The method of authenticating an RFID tag in accordance with claim 2 , wherein the hash function is selected from the group consisting of an SHA-1 function, an SHA-1 HMAC function, an SHA-2 function, and an MD5 function.

4. The method of authenticating an RFID tag in accordance with claim 1 , wherein creating an authentication signature comprises:
concatenating the unique identification code (UID) and the secret key to create a bitstring; and
performing a hash function on the bitstring to obtain the authentication signature.

5. The method of authenticating an RFID tag in accordance with claim 4 , wherein the hash function is selected from the group consisting of an SHA-1 function, an SHA-1 HMAC function, an SHA-2 function, and an MD5 function.

6. The method of authenticating an RFID tag in accordance with claim 4 , further comprising:
dividing the authentication signature into a plurality of bitstrings of equal length;
performing an XOR operation on a first of the plurality of bitstrings and second of the plurality of bitstrings to obtain at least one of an intermediate result or a final result.

7. The method of authenticating an RFID tag in accordance with claim 6 , further comprising:
performing an XOR operation on a most recently computed intermediate result and a subsequent one of the plurality of bitstrings to obtain at least one of an intermediate result or a final result.

8. The method of authenticating an RFID tag in accordance with claim 1 , wherein the function for which access is attempted is selected from the group consisting of a read function, a write function, and a read-write function.

9. A system for preparing a surgical instrument for use in an electrosurgical procedure, comprising:
a surgical instrument having an RFID tag, wherein the RFID tag comprises:
a unique identifier readable by a preparation unit; and
a password module configured to store a password and to return a status indicating whether a proffered password is equal to the stored password; and a preparation unit, comprising:
an RFID communication unit;
a processor operably coupled to the RFID communication unit; and
a memory operably coupled to the processor storing a secret key and having a set of instructions for:
reading the unique identifier of the RFID tag of the surgical instrument;
generating an authentication signature based at least in part upon encrypting the secret key with the unique identifier of the RFID tag of the surgical instrument; and
storing the authentication signature as a password in the password module.

10. The system for preparing a surgical instrument for use in an electrosurgical procedure in accordance with claim 9 , wherein the password is associated with a function of the RFID tag.

11. The system for preparing a surgical instrument for use in an electrosurgical procedure in accordance with claim 10 , wherein the RFID tag further comprises a read-write memory and a function of the RFID tag is selected from the group consisting of read-enabling the read-write memory, write-enabling the read-write memory, and read-write-enabling the read-write memory.

12. The system for preparing a surgical instrument for use in an electrosurgical procedure in accordance with claim 9 , wherein the RFID tag further comprises a read-write memory and wherein the set of instructions further comprises instructions configured to initialize a data structure within the read-write memory.

13. The system for preparing a surgical instrument for use in an electrosurgical procedure in accordance with claim 12 , wherein the data structure is configured to store data selected from the group consisting of a usage count, a manufacturing date, a manufacturer serial number, an expiration date, calibration data, historical data, certification data, and operational limit parameters.

14. The system for preparing a surgical instrument for use in an electrosurgical procedure in accordance with claim 9 , wherein the authentication signature is generated at least in part upon a cryptographic hash of the secret key and the unique identifier of the RFID tag.

15. The system for preparing a surgical instrument for use in an electrosurgical procedure in accordance with claim 14 , wherein the cryptographic hash is selected from the group consisting of an MD5 hash, an SHA-1 hash, an SHA-1 HMAC function, and an SHA-2 hash.

16. A system for authenticating a surgical instrument for use during an electrosurgical procedure, comprising:
a surgical instrument having an RFID tag, wherein the RFID tag comprises:
a unique identifier readable by an authentication unit; and
a password module storing a password and configured to return a status indicating whether a proffered password is equal to the stored password; and

an authentication unit, comprising:
an RFID communication unit;
a processor operably coupled to the RFID communication unit; and
a memory operably coupled to the processor storing a secret key and having a set of instructions for:
reading the unique identifier of the RFID tag of the surgical instrument;
generating an authentication signature based at least in part upon encrypting the secret key with the unique identifier of the RFID tag of the surgical instrument;
proffering the authentication signature as a password to the password module; and
receiving a status indicating whether the proffered password is equal to the stored password.

17. The system for authenticating a surgical instrument for use during an electrosurgical procedure in accordance with claim 16 , further comprising an electrosurgical generator operably coupled to the processor.

18. The system for authenticating a surgical instrument for use during an electrosurgical procedure in accordance with claim 17 , wherein operation of the electrosurgical generator is inhibited if the received status indicates the proffered password does not equal the stored password.

19. The system for authenticating a surgical instrument for use during an electrosurgical procedure in accordance with claim 16 , wherein the RFID tag further comprises a read-write memory and wherein the set of instructions further comprises instructions configured to modify data within the read-write memory.

20. The system for authenticating a surgical instrument for use during an electrosurgical procedure in accordance with claim 16 , wherein the authentication signature is g

Assignees

• Covidien Lp

Inventors

• Klammer Peter F
• Paterson William G

Classifications

• G06F21/44 Primary

  Program or device authentication · CPC title

• H04W12/06

  Authentication · CPC title

• H04W12/04

  Key management, e.g. using generic bootstrapping architecture [GBA] · CPC title

• G06Q10/08

  Logistics, e.g. warehousing, loading or distribution; Inventory or stock management · CPC title

• H04L9/0863

  involving passwords or one-time passwords (network architectures or network communication protocols for using one-time keys in a packet data network H04L63/067) · CPC title