Generating cryptographic checksums

US10396996B2 · kind B2 · utility

Assignee

• Telefonaktiebolaget LM Ericsson (Publ) · SE

Inventors

• Mats Näslund · Bromma, SE
• Elena Dubrova · Sollentuna, SE
• Fredrik Lindqvist · Järfälla, SE
• Göran Selander · Bromma, SE

Key dates

• Filing date: Aug 19, 2014
• Grant date: Aug 27, 2019
• Expiry date: May 16, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L2209/34
• WIPO field: Digital communication
• WIPO sector: Electrical engineering

Abstract

A method (500) of generating a cryptographic checksum for a message M(x) is provided. The method comprises pseudo-randomly selecting (502) at least two irreducible polynomials pi(x). Each irreducible polynomial pi(x) is selected based on a first cryptographic key from the set of irreducible polynomials of degree ni over a Galois Field. The method further comprises calculating (503) a generator polynomial p(x) of degree n=formula (I) as a product of the N irreducible polynomials formula (II), and calculating (505) the cryptographic checksum as a first function g of a division of a second function of M(x), ƒ(M(x)), modulo p(x), i.e., g(ƒ(M(x)) mod p(x)). By replacing a standard checksum, such as a Cyclic Redundancy Check (CRC), with a cryptographic checksum, an efficient message authentication is provided. The proposed cryptographic checksum may be used for providing integrity assurance on the message, i.e., for detecting random and intentional message changes, with a known level of security. Further, a corresponding computer program, a corresponding computer program product, and a checksum generator for generating a cryptographic checksum, are provided.