System and methods for data encryption using public key cryptography

• US 5,559,889 A
• Filed: 03/31/1995
• Issued: 09/24/1996
• Est. Priority Date: 03/31/1995
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Merz, William A., Easter, Randall J.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US08/414,852
• Time in Patent Office: 543 Days
• Field of Search: 380/21, 380/30
• US Class Current: 380/30
• CPC Class Codes: G06F 12/1408 by using cryptography for digital transmission H04L9/00
• CPC Class Codes: G06F 21/72 in cryptographic circuits
• CPC Class Codes: G06F 21/86 Secure or tamper-resistant housings
• CPC Class Codes: G06F 2207/7219 Countermeasures against side channel or fault attacks
• CPC Class Codes: G06F 2211/008 Public Key, Asymmetric Key, Asymmetric Encryption
• CPC Class Codes: H04L 9/0625 with splitting of the data block into left and right halves, e.g. Feistel based algorithms, DES, FEAL, IDEA or KASUMI
• CPC Class Codes: H04L 9/0643 Hash functions, e.g. MD5, SHA, HMAC or f9 MAC
• CPC Class Codes: H04L 9/0897 involving additional devices, e.g. trusted platform module [TPM], smartcard or USB
• CPC Class Codes: H04L 9/302 involving the integer factorization problem, e.g. RSA or quadratic sieve [QS] schemes

Abstract

An integrated circuit ("IC") chip is provided having both a public key cryptographic engine and a fuse array thereon. The fuse array is hardwired to the public key cryptographic engine and is encoded with a private key for use by the cryptographic engine. Specifically, prior to encapsulation of the IC chip, the fuse array is encoded using a laser ablation process. Upon encapsulation, the private key is permanently sealed and secured within the IC chip. The fuse array may also have a public key hash value and a serial number encoded therein.

Claims

1. An integrated circuit ("IC") chip for use in a cryptographic system, said IC chip comprising:

a non-volatile memory containing a private

key; and

a public key cryptographic engine coupled to said non-volatile memory, said public key cryptographic engine using said private key during operation.

2. The system of claim 1, wherein said non-volatile memory comprises a fuse array, said private key being encoded into said fuse array during fabrication of said IC chip.

3. The system of claim 1, wherein said non-volatile memory further includes a value representative of a public key encoded therein.

4. The system of claim 3, wherein said value comprises a public key hash value.

5. The system of claim 1, wherein said non-volatile memory further includes a serial number encoded therein which corresponds to said private key.

6. The system of claim 1, wherein said IC chip further includes a programmable memory coupled to said public key cryptographic engine for storing a public key.

7. The system of claim 1, wherein said non-volatile memory comprises a fuse array, said private key being encoded into said fuse array during fabrication of said IC chip, and wherein said fuse array further includes a public key hash value encoded therein for use in verifying a public key.

8. The system of claim 1, wherein the operation of the cryptographic engine includes an RSA-type operation.

9. The system of claim 7, wherein said fuse array further includes a serial number encoded therein corresponding to the public and private keys, and wherein the operation of the cryptographic engine includes an RSA-type operation.