Abstract:
A method and a circuit for controlling the access to at least one resource of an electronic circuit, in which a test of the value of a counter over at least one bit conditions the access to the resource, the counter being automatically reset after a time period independent from whether the circuit is powered or not.
Abstract:
A method of derivation, by an electronic circuit, of a first key from a second key, wherein: at least one third key is derived from the second key and is used to derive the first key; and a value of a counter, representative of the number of first keys, conditions the derivation of a new value of the third key.
Abstract:
A system for injecting faults by laser beams into an electronic circuit including: at least two lasers capable of emitting approximately parallel beams; at least one optical system receiving, on the magnifying side, the beams; and a support of the integrated circuit placed on the reducing side of the optical system.
Abstract:
A method and a circuit for controlling the access to at least one resource of an electronic circuit, in which a test of the value of a counter over at least one bit conditions the access to the resource, the counter being automatically reset after a time period independent from whether the circuit is powered or not.
Abstract:
A method for protecting at least one section of a program executed by a microcontroller, included before execution of the section, decrementing or incrementing at least one first counter and storing its state in a non-volatile memory of the microcontroller; in case of the detection of an attack attempt by the microcontroller, activating a flag in the microcontroller RAM; and at the end of the execution of the program section, checking the flag state.
Abstract:
A method and a circuit for protecting at least one piece of information contained in an electronic circuit by disabling at least one function of the circuit in case of detection of a number of abnormal operations greater than a threshold, in which the disabling of the function is temporary, of a duration independent from whether the circuit is powered or not.
Abstract:
A method and a device for converting a first bus including at least a data wire and a clock wire into a single-wire bus, wherein a data bit of the first bus is converted on half a period of the clock signal for transmission over the second bus, a waiting pattern being placed on the second bus during the other half-period.
Abstract:
A method of obtaining, in an electronic circuit, at least one first key intended to be used in a cryptographic mechanism, on the basis of at least one second key contained in the same circuit, the first key being stored in at least one first storage element of the circuit, the first storage element being reinitialized automatically after a duration independent of the fact that the circuit is or is not powered. Also described are applications of this method to encrypted transmissions, usage controls, as well as an electronic circuit implementing these methods.
Abstract:
A method and a circuit for protecting data contained in an electronic circuit against a disturbance of its operation, in which a detection of a disturbance conditions the incrementing or the decrementing of a counter over at least one bit, the counter being automatically reset at the end of a time period independent from the fact that the circuit is or not powered.
Abstract:
A method and a circuit of automatic control of the execution of a program by a microprocessor, including: assigning a digital decrement or increment to at least one function of the program; assigning a digital increment, respectively decrement, to at least one section considered as critical as to the program execution and called by the function; setting a counter to a first value; decrementing, respectively incrementing, the counter once per function before a call to a critical section; incrementing, respectively decrementing, the counter on each correct execution of a section; and comparing the current value of the counter with a predetermined critical threshold.