Abstract:
A method of implementing security in a modular exponentiation function for cryptographic operations is provided. A key is obtained as a parameter when the modular exponentiation function is invoked. The key may be one of either a public key or a private key of a cryptographic key pair. Within the modular exponentiation function, the method ascertains whether the key is greater than L bits long, where L is a positive integer. A countermeasure against an attack is implemented if the key is greater than L bits long. The countermeasure may include one or more techniques (e.g., hardware and/or software techniques) that inhibit or prevent information about the key from being ascertained through analysis. One or more exponentiation operations may then be performed using the key. The same modular exponentiation function may be used to perform encryption and decryption operations but with different keys.
Abstract:
Die Erfindung betrifft eine Vorrichtung (100) zur Ausführung eines Rechenverfahrens, insbesondere eines kryptografischen Verfahrens, wobei die Vorrichtung (100) eine primäre Funktionseinheit (110) aufweist, die zur Ausführung wenigstens eines Teils des Rechenverfahrens ausgebildet ist, dadurch gekennzeichnet, dass die Vorrichtung (100) wenigstens eine sekundäre Funktionseinheit (120) aufweist, die dazu ausgebildet ist, in einem vorgebbaren Zeitbereich ein oder mehrere physikalische Parameter der Vorrichtung (100) zu beeinflussen.
Abstract:
A first share value and a second share value may be received. A combination of the first share value and the second share value may correspond to an exponent value. The value of a first register is updated using a first equation that is based on the first and second share values and the value of a second register is updated using a second equation that is based on the second share value. One of the value of the first register or the value of the second register is selected based on a bit value of the second share value.
Abstract:
A power fingerprinting system is adopted for assessing integrity of a target computer-based system. In one implementation, the power fingerprinting system may receive, at a first module, side-channel information of a first target component of a system, the first module being collocated with the first target component; obtain a power fingerprint for the first target component based on the side-channel information for the first target component, the power fingerprint for the first target component representing a plurality of execution statuses of the first target component; receive, at a second module, side-channel information of a second target component of the system, the second module being collocated with the second target component, the power fingerprint for the second target component representing a plurality of execution statuses of the second target component; and obtain a power fingerprint for the second target component based on the side-channel information for the second target component.
Abstract:
A method is intended for protecting against fault attack(s) an electronic device (ED) comprising hardware and software capable of executing a sensitive process (SP) using a cache memory (CM) and implementing redundancy checks, said method comprising at least a step (i) during which said cache memory (CM) is filled with a first value originating from an external memory (EM), a step (ii) during which said first value is read into said cache memory (CM) and a step (iii) implementing at least a redundancy check, characterized in that it further comprises a fundamental step to guarantee that any redundant reading inside the redundancy check will extract a value from cache memory (CM) which is numerically equal to the genuine value in the external memory (EM).
Abstract:
A cryptographic device (200) reduces risk of external analysis of power consumed by an encryption circuit (206) by maintaining a substantially current draw on an external power input node (Nl) during operation. An active shunt current regulator (208) draws current to ground when not drawn by the encryption circuit (206). A low-pass filter (202) and a linear voltage regulator (204) smoothes power spikes and keeps power supply voltage constant at an input to the encryption circuit (206).
Abstract:
A device including a processor to perform an operation yielding a result, the processor including a register including bit storage elements and including a first and second section, each element being operative to store a bit value, and a power consumption mask module to determine whether the whole result can be completely written in half or less than half of the register, determine a balancing entry if the result can be completely written in half or less than half of the register, a write module to perform a single write operation to the register including writing the result and the balancing entry to the first and second section, respectively, if the result can be completely written in half or less than half of the register else writing the result of the operation across at least part of the first and second section. Related apparatus and methods are also described.
Abstract:
Methods and devices to encrypt and decrypt sensitive data to in a manner that provides secunty from external monitoring attacks is disclosed The encrypting device has access to a base secret cryptographic value (key) that is also known to the decrypting device The sensitive data are decomposed into segments, and each segment is encrypted with a separate encryption key denved from the base key and a message identifier to create a set of encrypted segments The encrypting device uses the base cryptographic value to create validators that prove that the encrypted segments for this message identifier were created by a device with access to the base key The decrypting device, upon receiving an encrypted segments uses validators to verify the message identifier and that the encrypted segment are unmodified
Abstract:
Disclosed is a novel circuit able to generate any logic combination possible as a function of the input logic signals. The circuit is described as a 2 input logistic map circuit but may be expanded to 3 or more inputs as required. Further disclosed is a universal logic array with variable circuit topology. A metallization layer and/or a via interconnection between cells in the array elements produce a circuit topology that implements a Boolean function and/or chaotic function and/or a logic function. The novel circuit provides a circuit topology for secure applications with no obvious physical correspondence between control signal values and input to output mapping. Further disclosed is a network which has a power signature independent of input signal state and output transition. This provides a very useful circuit to protect data from decryption from power signature analysis in secure applications.
Abstract:
La présente invention a pour objet un procédé de détection d'anomalies dans un circuit protégé par logique différentielle et traitant des variables logiques représentées par un couple de composantes (a t , a f ), un premier réseau de cellules (T) réalisant des fonctions logiques sur la première composante desdits couples, un deuxième réseau de cellules duales (F) fonctionnant en logique complémentaire sur la deuxième composante, les fonctions logiques étant réalisées par chaque couple de cellules (T, F) en une phase de précharge (21) mettant les variables dans un état connu à l'entrée des cellules suivie d'une phase d'évaluation (22) où un calcul est effectué par les cellules, ledit procédé étant caractérisé en ce qu'une anomalie est détectée par au moins un état non cohérent. L'invention a aussi pour objet un circuit protégé par logique différentielle comportant des moyens pour tester la cohérence entre les deux composantes des variables logiques durant les phases de précharge ou d'évaluation aux nœuds surveillés du circuit.