Method and device for code-based generation of a key pair for asymmetric cryptography

A key generation device for code-based generation of a key pair for asymmetric cryptography comprising one or more hardware processors, wherein the one or more hardware processors are configured to:

• generate a private key defining a linear code;
• determine a parity check or generator matrix for the linear code;
• blind a sub-matrix of the parity check or generator matrix;
• generate a blinded inverse matrix by inverting the blinded sub-matrix or by inverting a quadratic contained in the blinded sub-matrix;
• de-blind the blinded inverse matrix to generate an inverse matrix;
• and
• generate a public key for the private key using the inverse matrix,
• wherein the blinded inverse matrix is generated by determining an invertible quadratic matrix contained in the blinded sub-matrix of the parity check or generator matrix and inverting the invertible quadratic matrix, and wherein the inverse matrix is the inverse of the de-blinded invertible quadratic matrix.

A method for code-based generation of a key pair for asymmetric cryptography performed by a key generation device having a hardware security module and a hardware processor, the method comprising:

• generating a private key defining a linear code through the hardware security module;
• determining a parity check or generator matrix for the linear code by the hardware security module;
• blinding a sub-matrix of the parity check or generator matrix by the hardware security module;
• generating a blinded inverse matrix by inverting the blinded sub-matrix or by inverting a quadratic matrix contained in the blinded sub-matrix by the hardware processor;
• de-blinding the blinded inverse matrix to generate an inverse matrix by the hardware security module;
• and
• generating a public key for the private key using the inverse matrix by the hardware security module,
• wherein the blinded inverse matrix is generated by determining an invertible quadratic matrix contained in the blinded sub-matrix of the parity check or generator matrix and inverting the invertible quadratic matrix, and wherein the inverse matrix is the inverse of the de-blinded invertible quadratic matrix.