Tamper detection and secure power failure recovery circuit

• US 7,205,883 B2
• Filed: 10/07/2002
• Issued: 04/17/2007
• Est. Priority Date: 10/07/2002
• Status: Active Grant

• Current Assignee: Rainbow Technologies, Inc. (Thales SA)
• Original Assignee: SafeNet Incorporated (Thales SA)
• Inventors: Bailey, Doug
• Primary Examiner(s): Hofsass; Jeffery
• Assistant Examiner(s): AU, SCOTT D
• Application Number:
  US10/265,127
• Publication Number:
  US 20040066274A1
• Time in Patent Office: 1,653 Days
• Field of Search: 340/5.3, 713179-185, 235375-382
• US Class Current: 340/5.3
• CPC Class Codes: G06F 21/34 involving the use of external additional devices, e.g. dongles or smart cards
• CPC Class Codes: G06F 21/445 by mutual authentication, e.g. between devices or programs
• CPC Class Codes: G06F 21/554 involving event detection and direct action
• CPC Class Codes: G06F 2221/2113 Multi-level security, e.g. mandatory access control
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A security system including a token and a host system. The token includes volatile random access memory for storing security data for use during a step of secure authentication, an interface for providing communication with a host system when coupled thereto, and a processor. The processor performs the steps of authenticating a host system and the token, providing secure information to the host system upon authentication therewith, and re-authenticating the host system and the token in response to receipt of the secure information after a reset of the token has occurred.

Claims

1. A security system comprising:

a token comprising;

non-volatile random access memory (NVRAM) for storing security data for use during a step of secure authentication;

an interface for providing communication between the token and a host system when coupled thereto; and

a processor for performing the steps of;

receiving authentication data via the interface;

authenticating the token for performing security functions in response to correct authentication data;

providing secure information via the interface in response to the correct authentication data;

storing security data relating to the secure information within the NVRAM of the token in response to correct authentication data; and

re-authenticating the token for performing security functions using the security data stored in the NVRAM of the token in response to receipt of the secure information after a reset of the token has occurred.

2. A security system according to claim 1, wherein the host system further comprises:

an interface port for interfacing with the token,

a host processor for performing instructions in dependence upon instruction data, and

memory comprising instruction memory for storing of instructions for performing a step of secure re-authentication and non-volatile random access host memory for storing secure information received from the token and for use in secure re-authentication.

3. A security system according to claim 2, wherein the token further comprises:

a tamper detection device for detecting of tampering within the security system and for providing a tamper signal when tampering is detected; and

a memory clear circuit for clearing the security data within the token in response to the tamper signal.

4. A security system according to claim 3, wherein the tamper detection device comprises a secure housing and tamper detection circuitry, the non-volatile random access host memory being located within the physical boundaries of the secure housing.

5. A security system according to claim 4, wherein the tamper detection circuitry comprises a circuit for transmitting a tamper signal when then the secure housing is opened.

6. A security system according to claim 4, wherein the tamper detection circuitry comprises a circuit for transmitting a tamper signal when the security system is other than coupled to a ground.

7. A security system according to claim 4, wherein the tamper detection circuitry comprises a circuit for transmitting a tamper signal when the token is removed from a peripheral component interface slot.

8. A security system according to claim 1, comprising:

a voltage source internal to the token for providing a supply voltage to the token for a predetermined amount of time, when an external voltage source providing a supply voltage to the security system is disrupted.

9. A method for secure re-authentication of a secure server comprising the steps of:

transmitting authentication data from a host system to a token for authentication by the token;

receiving key data provided by the token at the host system in response to the transmitted authentication data;

storing the key data on the host system in non-volatile memory thereof;

storing re-authentication data within the token based on the key data provided to the host system;

providing the key data from the host system to the token for secure re-authentication by the token upon a resumption of power following a power failure resulting in a power outage to the token;

retrieving the stored re-authentication data within the token;

comparing the authentication data received from the host to the retrieved re-authentication data within the token; and

re-authenticating the host system to the token when the key data is correct key data associated with the stored re-authentication data.

10. A method for secure re-authentication according to claim 9, wherein authentication code is a password.

11. A method for secure re-authentication according to claim 9, wherein memory within the token is powered by a capacitor such that for a predetermined time after external power is other than provided to the token, the memory within the token retains data stored therein.

12. A method for secure re-authentication according to claim 9, wherein the step of storing re-authentication data within the token includes a step of encrypting the re-authentication data.

13. A method for secure re-authentication according to claim 9, further comprising the steps of:

generating on the token the key data.

14. A method for secure re-authentication according to claim 9, comprising the steps of:

generating on the token a first, a second, and a third additional secondary authentication key;

storing on the token at a least one of the first, second and third additional secondary authentication keys in memory; and

securing on the token secondary authorization key data with the at least one of the additional secondary authentication keys stored within memory.

15. A method for secure re-authentication according to claim 14, wherein the third additional secondary authentication key is created in dependence upon the first and the second additional secondary authentication keys.

16. A method for secure re-authentication according to claim 15, wherein the third additional secondary authentication key is created by means of a bit-wise exclusive-or (XOR) operation.

17. A method for secure re-authentication according to claim 12, further comprising the steps of:

creating on the host system an encryption key; and

sending from the host system to the token the encryption key.

18. A method for secure re-authentication according to claim 17, wherein at least one of a first, a second and a third additional secondary authorization keys is encrypted and decrypted with the encryption key.