PROGRAMMING NON-VOLATILE MEMORY IN A SECURE PROCESSOR

• US 20100095134A1
• Filed: 10/09/2009
• Published: 04/15/2010
• Est. Priority Date: 11/09/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Broadon Communications Corp. (Acer, Inc.)
• Inventors: Srinivasan, Pramila, Princen, John
• Granted Patent: US 8,601,247 B2
• Time in Patent Office: Days
• US Class Current: 713/193
• CPC Class Codes: G06F 21/33 using certificates
• CPC Class Codes: G06F 21/71 to assure secure computing or processing of information
• CPC Class Codes: G06F 21/72 in cryptographic circuits
• CPC Class Codes: G06F 21/73 by creating or determining hardware identification, e.g. serial numbers
• CPC Class Codes: H04L 2209/603 Digital right managament [DRM]
• CPC Class Codes: H04L 9/0869 involving random numbers or seeds
• CPC Class Codes: H04L 9/3066 involving algebraic varieties, e.g. elliptic or hyper-elliptic curves
• CPC Class Codes: H04L 9/3213 using tickets or tokens, e.g. Kerberos network architectures or network communication protocols for entities authentication using tickets in a packet data network H04L63/0807
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823

Abstract

An improved secure programming technique involves reducing the size of bits programmed in on-chip secret non-volatile memory, at the same time enabling the typical secure applications supported by secure devices. A technique for secure programming involves de-coupling chip manufacture from the later process of connecting to ticket servers to obtain tickets. A method according to the technique may involve sending a (manufacturing) server signed certificate from the device prior to any communication to receive tickets. A device according to the technique may include chip-internal non-volatile memory to store the certificate along with the private key, in the manufacturing process.

Claims

1. A method comprising:

providing a number to use as a small-signature private key;

computing a signature with a small-signature algorithm;

programming a compressed certificate into the chip-internal non-volatile memory of the device, wherein the compressed certificate includes a device ID, the small-signature private key, an issuer ID, and the signature;

enabling, in operation, a calling application to obtain a device certificate, wherein the device certificate is a function of the device ID, the issuer ID, the signature, and a public key, and wherein the public key is a function of the small signature private key, wherein the device certificate is larger than the compressed certificate.

2. The method of claim 1, further comprising programming the number in read-only memory (ROM) of the device.

3. The method of claim 1, further comprising generating the number as a secret seed random number.

4. The method of claim 1, further comprising computing the number using an elliptic curve digital signature algorithm (DSA).

5. The method of claim 1, further comprising:

receiving a request for a device certificate from the calling application;

reading the device ID, the small-signature private key, the issuer ID, and the signature from the non-volatile memory of the device;

computing the public key as a function of the small-signature private key and common parameters;

constructing the device certificate as a function of the device ID, the issuer ID, the public key, the signature, and the common parameters;

providing the device certificate to the calling application.

6. A system comprising:

a means for obtaining a device ID of a device;

a means for obtaining an issuer ID;

a means for providing a number to use as a small-signature private key;

a means for computing a signature with a small-signature algorithm;

a means for programming a compressed certificate into the chip-internal non-volatile memory of the device, wherein the compressed certificate includes the device ID, the small-signature private key, the issuer ID, and the signature;

a means for enabling a calling application to obtain a device certificate, wherein the device certificate is a function of the device ID, the issuer ID, the signature, and a public key, and wherein the public key is a function of the small signature private key, wherein the device certificate is larger than the compressed certificate.

7. The system of claim 6, further comprising a means for programming the number in read-only memory (ROM) of the device.

8. The system of claim 6, further comprising a means for generating the number as a secret seed random number.

9. The system of claim 6, further comprising a means for computing the number using an elliptic curve digital signature algorithm (DSA).

10. The system of claim 6, further comprising:

a means for receiving a request for a device certificate from the calling application;

a means for reading the device ID, the small-signature private key, the issuer ID, and the signature from the non-volatile memory of the device;

a means for computing the public key as a function of the small-signature private key and common parameters;

a means for constructing the device certificate as a function of the device ID, the issuer ID, the public key, the signature, and the common parameters;

a means for providing the device certificate to the calling application.