Method for authentication, RF chip document, RF chip reader and computer program products

An authentication method for trusted communication between a first party (A) and a second party (B) by combining password-based authentication and certificate-based authentication in such a manner that, for the certificate-based authentication, the first party (A) has a static key pair consisting of a private static key and a public static key and a certificate for the public static key issued by a certification body (C), and the certification body (C) is assigned a public key which is known by the second party (B) in such a manner

• that password-based authentication is first of all carried out with the following steps:
• the first party (A) and the second party (B)
• a) each generate an ephemeral key pair consisting of a private ephemeral key and a public ephemeral key,
• b) each interchange the public ephemeral key and validate the latter using a common password,
• c) generate and then validate a session key, on the basis of which a secure communication channel is established,
• that certificate-based authentication is then carried out with the following steps:
• d) the first party (A) calculates a transformation between its own ephemeral key pair from the password-based authentication and its own static key pair from the certificate-based authentication so as to obtain a transformation parameter,
• e) the first party (A) transmits the transformation parameter, together with the certificate issued by the certification body (C), to the second party (B) via the secure communication channel,
• f) the second party (B) applies the received transformation parameter to the public ephemeral key and/or the public static key associated with the first party (A) and in the process obtains at least one transformed public key, the correctness of which is checked, and
• g) the second party (B) validates the certificate received from the first party (A) using the public key associated with the certification body (C).