Abstract: A computer implemented anti-tamper system employing runtime profiling of software in order to decide where to inject integrity checks into the software, to enable verification of whether or not the software has been tampered with. Runtime profiling and analysis is used to record information about the application, in order to establish the locations and targets of runtime integrity checks in order to optimize protection security, while minimizing the performance penalty and the need for hand configuration.

Abstract: In a general aspect, an electronic device can include a device configured to transmit data by intracorporeal current. The device configured to transmit data by intracorporeal current can include a first electrode configured to be capacitively coupled with a body of a user or capacitively coupled in an intracorporeal current conduction path of the electronic device. The electronic device can further include a circuit configured to electrically bias the first electrode. The circuit can include an electric coil arranged near the first electrode. The electric coil can be configured to, in response to an alternating-current (AC) signal, generate an alternating magnetic field having field lines incident on the first electrode. The field lines incident on the first electrode can induce a current in the first electrode, where the current induces an electric field that generates an intracorporeal current.

Abstract: In a general aspect, a portable electronic device can include a digital display including a first electrically conductive plane. The first electrically conductive plane can be configured to neutralize electromagnetic radiation produced by the digital display. The portable electronic device can also include a data transmission device configured to transmit data by intracorporeal current. The data transmission device can include a first electrode that is configured to be capacitively coupled with a body of a user and a second electrode that includes the first electrically conductive plane. The first electrically conductive plane can be electrically coupled with an electrical ground of the data transmission device. The portable electronic device can further include a printed circuit including a second electrically conductive plane. The second electrically conductive plane can be included in the second electrode of the data transmission device.

Abstract: In a general aspect, a method for transmitting data between an NFC card and an external NFC device via a selected interface (e.g., contact or contactless), and further via a contactless interface of the NFC module when the contact interface of the NFC card is selected can include using an NFC card that includes an antenna circuit having an antenna coil with a magnetic axis and an electrically conductive screen extending near the antenna coil. The magnetic axis of the antenna coil can be substantially parallel to a plane defined by the NFC card and not cross the conductive screen. The contactless interface of the NFC card, when selected by the NFC card, can emit data by emitting bursts of magnetic field from the antenna coil, so as to compensate for effects of the conductive screen on a maximum distance for transmitting data by load modulation.

Abstract: A method in an elliptic curve cryptographic system, the method being executed by an electronic device and including a multiplication operation of multiplying a point of an elliptic curve by a scalar number, the point having affine coordinates belonging to a Galois field, the multiplication operation including steps of detecting the appearance of a point at infinity during intermediate calculations of the multiplication operation, and of activating an error signal if the point at infinity is detected and if the number of bits of the scalar number processed by the multiplication operation is lower than the rank of the most significant bit of an order of a base point of the cryptographic system.

Abstract: A cryptographic data processing method, implemented in an electronic device including a processor, the method including steps of providing a point of an elliptic curve in a Galois field, and a whole number, and of calculating a scalar product of the point by the number, the coordinates of the point and the number having a size greater than the size of words that may be processed directly by the processor, the scalar multiplication of the point by the number including steps of: storing scalar multiples of the point multiplied-by the number 2 raised to a power belonging to a series of whole numbers, setting a resulting point for each non-zero bit of the first number, adding the resulting point and one of the stored multiple points, and providing at the output of the processor the resulting point as result of the scalar product.

Abstract: A memory including at least one line to which memory cells are coupled. A control circuit is configured to emit an end-of-operation signal at the end of the execution of an operation on at least one memory cell, and a glitch detection circuit coupled to the memory line is configured to supply a glitch detection signal when a falling edge of the amplitude of a voltage signal appears on the memory line in the absence of the end-of-operation signal.

Abstract: In a general aspect, a method for transmitting data by inductive coupling can include applying, at a rate of a data-carrying signal, a plurality of bursts of a periodic signal to a tuned inductive antenna circuit. The method can further include producing, in the tuned inductive antenna circuit, an antenna signal, the antenna signal generating a magnetic field. The method can further include delimiting an amplitude of each burst of the plurality of bursts of the periodic signal in accordance with an envelope signal, the envelope signal having a rising edge and a falling edge. The delimiting can include shaping the falling edge of the envelope signal using one of a digital shaping circuit and an analog shaping circuit, such that a slope of the falling edge of the envelope signal is flattened as compared to a square envelope signal.

Abstract: In a general aspect, a method can include: installing in a non-secure device a customized module for managing communications with a secure element, transmitting to the secure element first authentication data for authenticating the customized module, the customized module generating and transmitting to the secure element second authentication data for authenticating the customized module, if the secure element determines that the first and second authentication data are consistent with each other, establishing a secure communication link between the customized module and the secure element, by using the first or second authentication data, the non-secure device transmitting a command to the secure element, for an application installed in the secure element, and the secure element executing the command only if the command is sent via the secure communication link.

Abstract: In a general aspect, a method can include establishing a contactless communication channel with a contactless transaction terminal and receiving a command from the contactless transaction terminal. The command can include an identifier of an application. The method can also include selecting, in a table in response to the command, an instance identifier corresponding with an instance of the application from a plurality of instance identifiers corresponding, respectively, with different instances of the application. Each instance identifier can be associated with a state indicator, and the state indicator associated with the selected instance identifier can specify that the corresponding instance of the application is in a selectable state.

Abstract: The detection of locking of a free running oscillator (FRO) is disclosed, including taking periodic samples of the FRO output, storing each new sample in a sample storage medium, each time a new sample is stored searching the stored samples for at least one repeating pattern, counting consecutive sampling instances in which a repeating pattern is found, and indicating when the count reaches a preselected threshold number.

Abstract: This disclosure relates to methods for generating a prime number, which can be implemented in an electronic device. An example method can include calculating a candidate prime number using a formula Pr=2P·R+1, where P is a prime number and R is an integer. The method can also include applying the Pocklington primality test to the candidate prime number and rejecting the candidate prime number if it fails the Pocklington test. The integer can be generated from an invertible number belonging to a set of invertible elements modulo the product of numbers belonging to a group of small prime numbers greater than 2, where the candidate prime number is not divisible by any number of the group. The prime number P having a number of bits equal to within one bit, to half or a third of the number of bits of the candidate prime number.

Abstract: The invention relates to a method for generating a prime number, implemented in an electronic device, the method including steps of generating a prime number from another prime number using the formula Pr=2P·R+1, where P is a prime number having a number of bits lower than that of the candidate prime number, and R is an integer, and applying the Pocklington primality test to the candidate prime number, the candidate prime number being proven if it passes the Pocklington test. According to the invention, the size in number of bits of the candidate prime number is equal to three times the size of the prime number, to within one unit, the generated candidate prime number being retained as candidate prime number only if the quotient of the integer division of the integer by the prime number is odd.

Abstract: A fault detection method for an encryption/decryption system based on a block cipher comprises the steps of subjecting a state array (CST) to multiple rounds, each round comprising a same series of sequential operations transforming the state array; storing the state of a reference operation (ShiftRows) of a current round as a checkpoint state (CHK); storing the state of the reference operation in the next round as an intermediate state; applying one round of reciprocal operations to the intermediate state, starting from the reciprocal of the reference operation (InvShiftRows); and comparing the result state of said one round of reciprocal operations with the checkpoint state.

Abstract: In a general aspect, a method of writing data in a nonvolatile memory can include performing a first erase or program cycle to write regular data in a first memory cell of the non-volatile memory by (i) applying at least one erase or program pulse to the first memory cell and (ii) determining the state, erased or programmed, of the first memory cell, and repeating (i) and (ii) if the first memory cell is not in the desired state. The method can also include applying a predetermined number of erase or program pulses to write fake data in a second memory cell.

Abstract: An apparatus including inductive coupling communication circuitry configured to communicate in peer-to-peer mode with an identical apparatus includes an antenna coil presenting, relative to a longitudinal median or a transversal median axis of the antenna coil, an asymmetry corresponding to a coverage rate less than or equal to 0.6 if the antenna coil comprises 4 or more loops, less than or equal to 0.7 if the antenna coil comprises 3 loops, or less than or equal to 0.8 if the antenna coil comprises 1 or 2 loops.

Abstract: The invention relates to a method for managing non-volatile memory space in a secure processor comprising a secure non-volatile internal memory, the method comprising steps of: selecting data elements to remove from the internal memory, generating, by the secure processor, a data block comprising the selected data elements, and a signature computed from the selected data elements using a secret key generated by the secure processor, transmitting the data block by the secure processor, and storing the transmitted data block in an external memory.

Abstract: A method for executing an application in an NFC device, including steps during which: a contactless link is established between a first and a second NFC devices, the first NFC device transmits through the contactless link an identifier memorized by the first NFC device, the second NFC device transmits through the contactless link an application identifier, the second NFC device transmits to an application server the identifier of the first NFC device and the application identifier, the application server transmits to an authentication server the identifier of the first NFC device and the application identifier, the authentication server verifies the identification data, and if the first NFC device and the application are identified, the authentication server authorizes the two NFC devices to execute the application by transmitting to the application server an identifier of a user of the first NFC device, corresponding to the identifier of the first NFC device.

Abstract: The present invention relates to a near field communication device configured to establish a near field communication channel with an external device, and provide a first host processor with application data sent by the external device. The device is configured to provide a second host processor with notifications relating to the nature or content of application data provided to the first host processor, and configure the notifications according to a characteristic parameter of an application in the framework of which the external device sends data to the first host processor.

Abstract: The present invention relates to a method for performing an iterative calculation of exponentiation of a large datum, the method being implemented in an electronic device (DV1) and comprising calculations of squaring and multiplying large variables performed in parallel, by squaring (SB1) and multiplication (SM1) blocks, the method comprising steps of: while a temporary storage buffer memory is not full of unused squares, triggering a calculation by the squaring block for a bit of the exponent, when the squaring block is inactive, storing each square provided by the squaring block in the buffer memory, if the bit of the corresponding exponent is on 1, and while the buffer memory contains an unused square, triggering a calculation by the multiplication block concerning the unused square, when the multiplication block is inactive.