Tamper detection and secure power failure recovery circuit

• US 20040066274A1
• Filed: 10/07/2002
• Published: 04/08/2004
• Est. Priority Date: 10/07/2002
• Status: Active Grant

• Current Assignee: Rainbow Technologies, Inc. (Thales SA)
• Original Assignee: Rainbow Technologies, Inc. (Thales SA)
• Inventors: Bailey, Doug
• Granted Patent: US 7,205,883 B2
• Time in Patent Office: Days
• 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 is disclosed, including a token as well as a host system. The token consists of 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. Alternatively, the token contains an internal voltage source for providing a supply voltage to the security system for a predetermined amount of time, when an external voltage source providing a supply voltage to the security system is disrupted, a tamper detection device for detecting an absence of a ground connected to the token and for providing a tamper signal when a ground is detected as absent, and a volatile random access memory clear circuit for clearing the security data within the volatile random access memory in response to the tamper signal.

Claims

1. A security system comprising:

a token comprising;

volatile random access memory 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 via the interface authentication data;

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

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

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

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

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

a host system comprising;

an interface port for interfacing with a token,

a 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 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 authenticating to the token;

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

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;

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

determining if the key data is correct key data associated with the stored re-authentication data; and

,

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

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 comparison operation.

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

creating on the host system an echo-avoiding encryption key; and

sending from the host system to the token the echo-avoiding encryption key.

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

19. A security system comprising:

a token comprising;

volatile random access memory for storing security data for use during a step of secure authentication;

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

an interface for providing communication with a host system when coupled thereto;

a tamper detection device for detecting an absence of a ground connected to the token and for providing a tamper signal when a ground is detected as absent; and

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

20. A security system according to claim 19, wherein the tamper detection circuitry comprises a circuit for sending out a tamper signal when the token is removed from a peripheral component interface slot.

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

storing re-authentication data within memory within a token;

detecting a presence of a ground coupled to the token; and

,

when a ground is other than coupled to the token, erasing the re-authentication data within the memory.

22. A method for secure re-authentication according to claim 21, wherein the 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.