GD32W51x User Manual
925
27.
Cryptographic Acceleration Unit (CAU)
27.1.
Overview
The cryptographic acceleration unit (CAU) is used to encipher and decipher data with DES,
Triple-DES or AES (128, 192, or 256) algorithms. It is fully compliant implementation of the
following standards:
The Data Encryption Standard (DES) and the Triple Data Encryption Algorithm (TDEA)
are announced by Federal Information Processing Standards Publication (FIPS) 46-3,
October 25, 1999. It follows the American National Standards Institute (ANSI) X9.52
standard.
The Advanced Encryption Standard (AES) is announced by Federal Information
Processing Standards Publication 197, November 26, 2001.
DES/TDES/AES algorithms with different key sizes are supported to perform data encryption
and decryption in the CAU in multiple modes.
The CAU is a 32-bit peripheral, DMA transfer is supported and data can be accessed in the
input and output FIFO.
27.2.
Characteristics
DES, TDES and AES encryption/decryption algorithms are supported.
Multiple modes are supported respectively in DES, TDES and AES, including
Electronic codebook (ECB), Cipher block chaining (CBC), Counter mode (CTR),
Galois/counter mode (GCM), Galois message authentication code mode (GMAC),
Counter with CBC-MAC (CCM), Cipher Feedback mode (CFB) and Output Feedback
mode(OFB).
DMA transfer for incoming and outgoing data is supported.
DES/TDES
Supports the ECB and CBC chaining algorithms
Two 32-bit initialization vectors (IV) are used in CBC mode
8*32-bit input and output FIFO
Multiple data types are supported, including No swapping, Half-word swapping Byte
swapping and Bit swapping
Data are transferred by DMA, CPU during interrupts, or without both of them
AES
Supports the ECB, CBC, CTR, GCM, GMAC, CCM, CFB and OFB chaining algorithms
Supports 128-bit, 192-bit and 256-bit keys
Four 32-bit initialization vectors (IV) are used in CBC, CTR, GCM, GMAC, CCM, CFB