A technique for generating a keystream (128) for ciphering or deciphering a data stream (122) is provided. As to a method aspect of the technique, a nonlinear feedback shift register, NLFSR (112), including n register stages implemented in a Galois configuration is operated. At least one register stage of the implemented n register stages is representable by at least one register stage of a linear feedback shift register, LFSR. A first subset of the implemented n register stages is representable by a second subset of a second NLFSR. A number of register stages receiving a nonlinear feedback in the second NLFSR is greater than one and less than a number of register stages receiving a nonlinear feedback in the implemented NLFSR. The keystream (128) is outputted from a nonlinear output function (118). An input of the nonlinear output function (118) is coupled to at least two of the implemented n register stages of the NLFSR (112).

Combined physical unclonable function (PUFs); methods, apparatuses, systems, and computer program products for enrolling combined PUFs; and methods, apparatuses, systems, and computer program products for authenticating a device physically associated with a combined PUF are described. In an example embodiment, a combined PUF includes a plurality of PUFs and one or more logic gates. Each PUF includes a plurality of stages and an arbiter configured to generate a single PUF response based on response portions generated by the plurality of stages. The one or more logic gates are configured to combine the single PUF response for each of the plurality of PUFs in accordance with a combination function to provide a combined response.

Methods, systems, and devices for encrypting and decrypting data. In one implementation, an encryption method includes inputting plaintext into a recurrent artificial neural network, identifying topological structures in patterns of activity in the recurrent artificial neural network, wherein the patterns of activity are responsive to the input of the plaintext, representing the identified topological structures in a binary sequence of length L and implementing a permutation of the set of all binary codewords of length L. The implemented permutation is a function from the set of binary codewords of length L to itself that is injective and surjective.

In a general aspect, a method can include: executing an operation of a program that loads an arbitrarily chosen value of an initial data item of a series of ordered data; executing a series of calculation operations distributed in the program, that calculate a current data item based on a preceding data item; performing a final calculation operation of the series of operations that calculates a final data item of the data series; and executing an operation of the program that detects a program execution error by comparing the current data item of the data series with an expected value of the current data item or the final data item, the final data item having an expected value that is independent of the number of data items in the data series and is calculated based on the current data item of the data series and a final compensation data item.

Methods, systems, and apparatus, including medium-encoded computer program products, for secure storage and retrieval of information, such as private keys, useable to control access to a blockchain, include, in at least one aspect, a method including: identifying for an action an associated private-keys group out of different private-keys groups, each having an associated cryptographic group key; decrypting, at a first computer, a first level of encryption of a private key associated with the action using the associated cryptographic group key; decrypting, at a second computer distinct from the first computer, a second level of encryption of the private key associated with the action using a hardware-based cryptographic key used by the second computer; using, at the second computer, the private key associated with the action in a process of digitally signing data to authorize the action; and sending the digitally signed data to a third computer to effect the action.

In accordance with some embodiments, an apparatus includes a crypto engine that provides device independent crypto services. The apparatus includes a housing arranged to hold a device. The apparatus also includes a non-transitory memory that further includes a key store for storing a first key. The apparatus further includes a communication device at least partially supported by the housing and connectable to the device to establish a communication channel with the device. The apparatus also includes a controller (e.g., a crypto engine) that receives, via the communication channel, a first portion of data from the device, performs a cryptographic operation on the first portion of the data using the first key to generate a modified first portion, sends, via the communication channel, the modified first portion to the device, and enables the device to derive a second portion of the data using the modified first portion.

The disclosure concerns a method of protecting a calculation on a first number and a second number, including the steps of: generating a third number including at least the bits of the second number, the number of bits of the third number being an integer multiple of a fourth number; dividing the third number into blocks each having the size of the fourth number; successively, for each block of the third number: performing a first operation with a first operator on the contents of a first register and of a second register, and then on the obtained intermediate result and the first number, and placing the result in a third register; and for each bit of the current block, performing a second operation by submitting the content of the third register to a second operator with a function of the rank of the current bit of the third number, and then to the first operator with the content of the first or of the second register according to state “0” or “1” of said bit, and placing the result in the first or second register.

Disclosed herein is a data storage device. A data port transmits data between a host computer system and the data storage device. A non-volatile storage medium stores encrypted user content data and a cryptography engine connected between the data port and the storage medium uses a cryptographic key to decrypt the encrypted user content data. The access controller receives from a manager device a public key. The public key is associated with a private key stored on a device to be authorized. The controller determines a user key that provides access to the cryptographic key; encrypts the user key based on the public key and such that the user key is decryptable based on the private key stored on the device to be authorized; and stores, on the data store, authorization data indicative of the encrypted user key.

Instructions and logic provide for a Single Instruction Multiple Data (SIMD) SM4 round slice operation. Embodiments of an instruction specify a first and a second source data operand set, and substitution function indicators, e.g. in an immediate operand. Embodiments of a processor may include encryption units, responsive to the first instruction, to: perform a slice of SM4-round exchanges on a portion of the first source data operand set with a corresponding keys from the second source data operand set in response to a substitution function indicator that indicates a first substitution function, perform a slice of SM4 key generations using another portion of the first source data operand set with corresponding constants from the second source data operand set in response to a substitution function indicator that indicates a second substitution function, and store a set of result elements of the first instruction in a SIMD destination register.

In one embodiment, a system includes a non-volatile memory that may serve as both the main memory system and the backing store (or persistent storage). In some embodiments, the non-volatile memory is divided into a main memory portion and a persistent portion. Data in the main memory operation may be encrypted using one or more first keys, and data in the persistent portion may be encrypted using one or more second keys, in an embodiment. The volatile behavior of main memory may be implemented by discarding the one or more first keys in a power down event or other event that indicates a loss of main memory data, while the one or more second keys may be retained. In one embodiment, the physical address space of the non-volatile memory may be a mapping from a second physical address space that is used within the system.