System and method for security of computing devices

• US 20040039924A1
• Filed: 01/14/2003
• Published: 02/26/2004
• Est. Priority Date: 04/09/2001
• Status: Abandoned Application

• Current Assignee: Kinglite Holdings Inc.
• Original Assignee: Kinglite Holdings Inc.
• Inventors: Wang, Kai, Barr, John D., Kotla, Pannaga, Williams, Stephen D., Pitard, David, Baldwin, Robert W., Casillas, Jose A., Abgrall, Jean-Paul, Jablon, David P., Markey, Timothy J.
• Application Number:
  US10/342,709
• Publication Number:
  US 20040039924A1
• Time in Patent Office: Days
• US Class Current: 713/189
• CPC Class Codes: G06F 21/53 by executing in a restricted environment, e.g. sandbox or secure virtual machine
• CPC Class Codes: G06F 21/57 Certifying or maintaining trusted computer platforms, e.g. secure boots or power-downs, version controls, system software checks, secure updates or assessing vulnerabilities
• CPC Class Codes: G06F 21/575 Secure boot
• CPC Class Codes: G06F 21/73 by creating or determining hardware identification, e.g. serial numbers
• CPC Class Codes: G06F 21/74 operating in dual or compartmented mode, i.e. at least one secure mode
• CPC Class Codes: G06F 21/79 in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 21/86 Secure or tamper-resistant housings
• CPC Class Codes: G06F 2221/2105 Dual mode as a secondary aspect
• CPC Class Codes: G06F 2221/2129 Authenticate client device independently of the user
• CPC Class Codes: G06F 2221/2141 Access rights, e.g. capability lists, access control lists, access tables, access matrices
• CPC Class Codes: G06F 2221/2145 Inheriting rights or properties, e.g., propagation of permissions or restrictions within a hierarchy
• CPC Class Codes: G06F 2221/2147 Locking files
• CPC Class Codes: G06F 2221/2149 Restricted operating environment
• CPC Class Codes: G06F 2221/2153 Using hardware token as a secondary aspect
• CPC Class Codes: H04L 2209/20 Manipulating the length of blocks of bits, e.g. padding or block truncation
• CPC Class Codes: H04L 2209/34 Encoding or coding, e.g. Huffman coding or error correction
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/603 Digital right managament [DRM]
• CPC Class Codes: H04L 2463/061 applying further key derivation, e.g. deriving traffic keys from a pair-wise master key cryptographic mechanisms or cryptographic arrangements for generation of secret information including derivation or calculation of cryptographic keys or passwords H04L9/0861
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/123 : received data contents, e.g. message integrity
• CPC Class Codes: H04L 9/0844 : with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys
• CPC Class Codes: H04L 9/0891 : Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04L 9/0894 : Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage

Abstract

System and method for securing a computing device using a master cryptographic key that is bound to the device. The master key is used to derive sensitive data that is transferred to storage that is only accessible in a restricted mode of operation. The master key is used to derive one or more application keys that are used to secure data that is specific to an application/device pair. Non-privileged programs can request functions that run in a more restricted mode to use these application keys. The restricted mode program checks the integrity of the non-privileged calling program to insure that it has the authority and/or integrity to perform each requested operation. One or more device authority servers may be used to issue and manage both master and application keys.

Claims

1. A method of sending a secure message between a first application program and a second application program by restricting the use of a cryptographic key to the first application program and the second application program, said first application program and the second application program running on a device, comprising:

providing a first key known to a cryptographic processing module;

providing an application container data structure that contains a cryptographically sealed form of the data for the first application program and second application program to access;

performing a cryptographic gatekeeping function that computes a cryptographic digest of a portion of an in-memory image of at least one of the first application program and second application program;

performing an integrity-check by the cryptographic processing module by examining the application container data structure, the cryptographic digest, and the first key to determine if at least one of the first application program and second application program is allowed to unseal the cryptographically sealed form of the data; and

authenticating, by the first application program, the secure message sent by the second application using the application container data structure.

2. The method of claim 1 further comprising performing a privacy operation by the cryptographic processing module that encrypts or decrypts the cryptographically sealed form of the data in the application container data structure using a key derived from at least the first key and cryptographic digest, and when the cryptographically sealed form of the data is to be encrypted, the crytographic processing module adds to the application container data structure the cryptographic digest before the encryption is performed.

3. The method of claim 1 further comprising providing an authorization buffer that specifies the result of the integrity-check, and wherein the cryptographic gatekeeping function confirms that the at least one of the first application program and second application program is allowed to unseal the cryptographically sealed form of the data.

4. The method of claim 1 wherein the integrity-check includes:

deriving a cryptographic variable from the cryptographic digest and the first key; and

using the cryptographic variable to check a message authentication code that is stored in the application container data structure.

5. The method of claim 1 wherein the integrity-check includes:

decrypting data derived from the application container data structure using a key derived from the first key to create a resulting value and comparing the resulting value to data derived from the cryptographic digest; and

allowing access to the cryptographically sealed form of the data if the resulting value is the same as the data derived from the cryptographic digest.

6. The method of claim 2 wherein the privacy operation includes:

deriving a cryptographic variable from the cryptographic digest and the first key, wherein the cryptographic variable is used to decrypt or encrypt a portion of the application container data structure.

7. The method of claim 1 wherein the first key is stored in a secure database indexed by a key ID.

8. The method of claim 1 wherein the device is one of an encryption/decryption hardware device and a limited access server.

9. A system for sending a secure message between a first application program and a second application program by restricting the use of a cryptographic key to the first application program and the second application program running on a device of said system, comprising:

a memory containing instruction sequences, a first key that is known to a cryptographic processing module, and an application container data structure that contains a cryptographically sealed form of the data for the first application program and second application program to access; and

,

a processor, coupled to the memory, said processor to execute the cryptographic processing module, said instruction sequences to cause the processor to;

compute a cryptographic digest of a portion of an in-memory image of at least one of the first application program and second application program;

perform an integrity-check by the cryptographic processing module by examining the application container data structure, the cryptographic digest, and the first key to determine if at least one of the first application program and second application program is allowed to unseal the cryptographically sealed form of the data; and

authenticate, by the first application program, the secure message sent by the second application using the application container data structure.

10. The system of claim 9 wherein said instruction sequences further cause the processor to perform a privacy operation by the cryptographic processing module that encrypts or decrypts the cryptographically sealed form of the data in the application container data structure using a key derived from at least the first key and cryptographic digest, and when the cryptographically sealed form of the data is to be encrypted, the crytographic processing module adds to the application container data structure the cryptographic digest before the encryption is performed.

11. The system of claim 9 further comprising an authorization buffer that specifies the result of the integrity-check, and wherein the system confirms that the at least one of the first application program and second application program is allowed to unseal the cryptographically sealed form of the data.

12. The system of claim 9 wherein said processor, in performing the integrity-check, further:

derives a cryptographic variable from the cryptographic digest and the first key; and

uses the cryptographic variable to check a message authentication code that is stored in the application container data structure.

13. A system of authenticating a device and an application program that is running on the device, said system comprising:

a hidden storage containing a first key;

a memory for storing instruction sequences; and

a processor, coupled to the hidden storage and the memory, said instruction sequences to cause the processor to;

execute a cryptographic gatekeeper module that runs in a restricted mode and computes a cryptographic digest of a portion of the application program; and

authenticate the device and the application program using the first key and the cryptographic digest.

14. The system of claim 13, wherein the application program is part of an operating system kernel.

15. The system of claim 13, wherein the application program and device are authenticated before the application program is allowed to access sensitive data.

16. The system of claim 13, wherein the first key is a shared key for use in a symmetric key cryptosystem.

17. The system of claim 13, wherein firmware controls the system during a system initialization process that begins in response to a power-on or reset signal.

18. The system of claim 13, wherein:

the hidden storage is in a system management random access memory which is not accessible by any program running in a normal operating mode of the system; and

the restricted operating mode is a system management mode in which access to the system management random access memory is permitted.

19. The system of claim 13, wherein the first key is generated in cooperation with a shared server that computes application keys to be shared with at least one other system.

20. The system of claim 13, wherein the shared server shares said application keys with the at least one other system to authenticate devices and device-bound applications.