Abstract: The present disclosure relates to a method and device for performing an elliptic curve cryptography computation comprising: twisting, by a first device based on a first index of quadratic or higher order twist (d), a first point (P?KB) on a first elliptic curve over a further elliptic curve twisted with respect to the first elliptic curve to generate a twisted key (PKB); transmitting the twisted key (PKB) to a further device; receiving, from the further device, a return value (ShS) generated based on the twisted key (PKB); and twisting, by the first device based on the first index of quadratic or higher order twist (d), the return value (ShS) over the first elliptic curve to generate a result (ShS?) of the ECC computation.

Abstract: The present disclosure relates to a method and device for performing an elliptic curve cryptography computation comprising: twisting, by a first device based on a first index of quadratic or higher order twist (d), a first point (P?KB) on a first elliptic curve over a further elliptic curve twisted with respect to the first elliptic curve to generate a twisted key (PKB); transmitting the twisted key (PKB) to a further device; receiving, from the further device, a return value (ShS) generated based on the twisted key (PKB); and twisting, by the first device based on the first index of quadratic or higher order twist (d), the return value (ShS) over the first elliptic curve to generate a result (ShS?) of the ECC computation.

Abstract: An access process for an electronic device includes storing encrypted partitions in a storage area of the electronic device, with each encrypted partition corresponding to a registered user. A secure element is received from a registered user, with the secure element storing a user key for decrypting an encrypted partition corresponding to the register user providing the user key. A temporary secure channel is established between the secure element and the electronic device, and a registered user associated to one of the encrypted partitions is authenticated in the electronic device. An identification of the registered user authenticated in the electronic device is transmitted to the secure device, and the user key of the authenticated registered user is transmitted from the secure element to the electronic device over the temporary secure channel.

Abstract: A method is to de-correlate electric signals emitted by an IC Card during computations as well as sensitive data involved in such computations. The method includes executing functions introducing respective electric signals which do not involve the sensitive data. Each of the functions is triggered by a timer having a value which is different at each step of executing the functions.

Abstract: An access method includes providing a secure element which stores at least a user key for decrypting one of the encrypted partitions; establishing a temporary secure channel between the secure element and the electronic apparatus; and authenticating in the electronic apparatus a user which is associated to one of the encrypted partitions. The method also includes transmitting an identification of the user authenticated and transmitting the user key from the secure element to the electronic apparatus over the temporary secure channel. The electronic apparatus is programmed to decrypt the encrypted partition and the encrypted partition of the authenticated user is not accessible to the authenticated user or to any other authenticated users in the electronic apparatus, if the user key of the authenticated user is not transmitted to the electronic apparatus.

Abstract: A method is to de-correlate electric signals emitted by an IC Card during computations as well as sensitive data involved in such computations. The method includes executing functions introducing respective electric signals which do not involve the sensitive data. Each of the functions is triggered by a timer having a value which is different at each step of executing the functions.