Nuvoton Technology Corporation

Kun-Yi Wu

Yu-Shan Li

Chun-Chi Chen

Ming-Ying Liu

A method for tamper protection in cryptographic calculations is provided. A cryptographic calculation includes a plurality of normal rounds and a plurality of redundant rounds. The method includes obtaining a first variable x and a second variable y using a random number generator; dividing the normal rounds into a first normal section and a second normal section, and dividing the redundant rounds into a first redundant section and a second redundant section according to the first variable x and the second variable y; executing the first normal section and the first redundant section in sequence using a clock signal; in response to completion of the first redundant section and a first calculation result of the first normal section and a second calculation result of the first redundant section being the same, executing the second normal section and the second redundant section in sequence to complete the cryptographic calculation.

Cipher accelerator and method for tamper protection in cryptographic operations

A cipher accelerator is provided. An encryption and decryption circuit is configured to perform an encryption and decryption operation according to a control signal. The encryption and decryption operation includes a plurality of normal rounds and a plurality of redundant rounds. A controller is configured to provide a control signal to the encryption and decryption circuit according to a first variable value and a second variable value. The encryption and decryption circuit is configured to divide the normal rounds into a first normal section and a second normal section according to the first variable value, and divide the redundant rounds into a first redundant section and a second redundant section according to the second variable value. The encryption and decryption circuit is configured to perform the first normal section, the first redundant section, the second normal section, and the second redundant section sequentially.

Cipher accelerator and differential fault analysis method for encryption/decryption operation

An encryption device is provided, which includes a controller, a random controller, a first functional unit, and a second functional unit. The controller generates a first enable signal and a second enable signal. When at least one of the first enable signal and the second enable signal is in a first logic level, the random controller generates a first random signal and a second random signal. The first functional unit performs the corresponding operation according to the first enable signal and the first random signal. The second functional unit performs the corresponding operation according to the second enable signal and the second random signal.

Encryption device and encryption method with clock gating unit and random-number generator

An addition mask value generator is provided. A first operation circuit is configured to obtain first intermediate data according to first output mask value and fourth output mask value. A second operation circuit is configured to obtain the addition output mask value of a first mask group according to first intermediate data and fourth input mask value. A third operation circuit is configured to obtain second intermediate data according to second output mask value and third output mask value. A fourth operation circuit is configured to obtain the addition output mask value of a second mask group according to second intermediate data and second input mask value. The first and second addition input mask values of first mask group are first and second input mask values. The first and second addition input mask values of second mask group are third input mask value and first intermediate data.

Addition mask value generator, encryptor and method for generating stream key

A carry-lookahead adder is provided. A first mask unit performs first mask operation on first input data with the first mask value to obtain first masked data. A second mask unit performs second mask operation on second input data with the second mask value to obtain second masked data. A first XOR gate receives the first and second mask values to provide a variable value. A half adder receives the first and second masked data to generate a propagation value and an intermediate generation value. A third mask unit performs third mask operation on the propagation value with the third mask value to obtain the third masked data. A carry-lookahead generator provides the carry output and the carry value according to carry input, the generation value, and the propagation value. The second XOR gate receives the third masked data and the carry value to provide the sum output.

Carry-lookahead adder, secure adder and method for performing carry-lookahead addition

A one-time programmable memory device is provided in the invention. The one-time programmable memory device includes a one-time programmable memory and a memory controller. The one-time programmable memory includes a first block, a second block and a third block. The first block includes a plurality of initial-address-unit groups and each initial-address-unit group includes a plurality of initial address units and each initial address unit corresponds to a variable to record the storage address of its corresponding variable. The second block includes a plurality of initial address control units and each initial address control unit corresponds to one of the variables to record the corresponding initial-address-unit group of each variable. The third block includes a plurality of storage units and each storage unit has a corresponding storage address. The memory controller is configured to assign the storage addresses to the variables.

One-time programmable memory device and fault tolerance method thereof

A data-processing device is provided. The data-processing device includes: a flash memory, a computation unit, and a flash-memory controller. The flash-memory controller is electrically connected to the computation unit, and configured to control access to the flash memory. The flash-memory controller allocates a first execute-only memory (XOM) setting and a second XOM setting in a first memory bank and a second memory bank of the flash memory, respectively. The flash-memory controller allocates one or more XOM spaces in the flash memory according to the first XOM setting or the second XOM setting.

Data-processing device and data-protection method thereof

A one-time programmable memory device is provided in the invention. The one-time programmable memory device includes a one-time programmable memory and a memory controller. The one-time programmable memory includes a first block and a second block. The first block includes a plurality of initial address units and each initial address unit corresponds to a variable to record the storage address of its corresponding variable, and wherein the second block includes a plurality of storage units and each storage unit has a corresponding storage address. The memory controller is coupled to the one-time programmable memory. The memory controller allocates the storage address to the variable. The content of each variable is stored in the storage unit corresponding to the storage address corresponding to the variable. The number of initial address units is smaller than the number of storage units.

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Tainan, Taiwan

Kun-Yi Wu