System and method for secured host-slave communication

摘要

Slave device circuitry, including processing circuitry which is configured to determine a new session identification value; determine a seed value using a secure hash algorithm on a previously determined seed value; determine a slave number from using the secure hash algorithm on the new session identification value, the determined seed value, and a serial number of the slave device associated with the slave device circuitry; receive a host number from the host imaging apparatus and calculate a session key using a hash-based algorithm computation on the host number, the slave number, the new session identification value, and a stored encryption key. The session key has a first portion for performing encryption and decryption operations on data to be transmitted and data received by the slave device, respectively, and a second portion for generating a new address value of the slave device for communicating with the host.

主权项

1. A supply item for an imaging apparatus, comprising:
a processor and memory coupled thereto having stored therein program code instructions which, when executed by the processor, cause the processor to:
following a predetermined event, determine a session identifier value;determine a new seed value based on a secure hash algorithm calculation on a seed value stored in the memory;calculate a slave random number from a predetermined number of bits resulting from a secure hash algorithm calculation on the session identifier value, the new seed value, and a serial number of the supply item;receive a host number from the imaging apparatus;calculate a session key by generating a cryptographic value using a secret key maintained in the memory and a concatenation of the host number, the slave random number, and the session identifier value, the session key being a single session key comprising a set of bits including a first subset of the set of bits and a second subset of the set of bits, the first and second subsets of the set of bits being separate from each other; anduse the first subset of the set of bits to perform encryption and decryption operations on data to be transmitted and data received by the supply item, respectively, and the second subset of the set of bits to generate a new address value for the supply item for communicating with the imaging apparatus.