INTEGRATED CIRCUIT FOR AUTHENTICATION OF CONSUMABLE STORAGE DEVICE

• US 20110208966A1
• Filed: 04/13/2011
• Published: 08/25/2011
• Est. Priority Date: 07/15/1997
• Status: Abandoned Application

• Current Assignee: Silverbrook Research Pty Limited
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: SILVERBROOK, KIA
• Application Number:
  US13/086,359
• Publication Number:
  US 20110208966A1
• Time in Patent Office: Days
• US Class Current: 713/168
• CPC Class Codes: G06F 21/31 User authentication
• CPC Class Codes: G06F 21/77 in smart cards
• CPC Class Codes: G06F 2221/2103 Challenge-response
• CPC Class Codes: G06F 2221/2129 Authenticate client device independently of the user
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: H04L 2209/043 of tables, e.g. lookup, substitution or mapping
• CPC Class Codes: H04L 2209/08 Randomization, e.g. dummy operations or using noise
• CPC Class Codes: H04L 9/002 Countermeasures against attacks on cryptographic mechanisms network architectures or network communication protocols for protection against malicious traffic H04L63/1441
• CPC Class Codes: H04L 9/3218 using proof of knowledge, e.g. Fiat-Shamir, GQ, Schnorr, ornon-interactive zero-knowledge proofs
• CPC Class Codes: H04L 9/3242 involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC
• CPC Class Codes: H04L 9/3271 using challenge-response

Abstract

An integrated circuit is provided for the authentication of a consumable storage device by an apparatus. The integrated circuit has a memory space which contains encrypted data defined by a message authentication code (MAC) applied to data relating to a consumable stored by the device. The MAC is a construction of an asymmetric cryptographic function whereby a public key K_T stored by another integrated circuit of the apparatus is used to encrypt a random number generated by the another integrated circuit. A secret key K_A stored by the integrated circuit is used to decrypt the encrypted random number. The decrypted random number is appended to data stored in the memory space. The secret key K_A is used to encrypt the appended random number and data, and the public key K_T is used to decrypt the encrypted random number appended to the data.

Claims

1. An integrated circuit for the authentication of a consumable storage device by an apparatus, the integrated circuit comprising a memory space which contains encrypted data defined by a message authentication code (MAC) applied to data relating to a consumable stored by the device, the MAC being a construction of an asymmetric cryptographic function whereby a public key K_T stored by another integrated circuit of the apparatus is used to encrypt a random number generated by said another integrated circuit, a secret key K_A stored by the integrated circuit is used to decrypt the encrypted random number, the decrypted random number is appended to data stored in the memory space, the secret key K_A is used to encrypt the appended random number and data, and the public key K_T is used to decrypt the encrypted random number appended to the data.

2. An integrated circuit as claimed in claim 1, in which the cryptographic function is a hash function such that the MAC is an algorithm known as HMAC.

3. An integrated circuit as claimed in claim 2 in which the hash function is one of an MD5 function and a SHA-1 function.

4. An integrated circuit as claimed in claim 2, in which the hash function is an SHA-1 function.

5. An integrated circuit as claimed in claim 4, which is configured to define a number of temporary registers and rotating counters and to calculate an output word on an iterative basis by calculating and allocating words to respective registers during processing of the SHA-1 function.