ST STM32L0x3 User Manual

AES hardware accelerator (AES) RM0367
436/1043 RM0367 Rev 7
Note: The chaining mode may be changed only when AES is disabled (bit EN of the AES_CR
register set).
Principle of each AES chaining mode is provided in the following subsections.
Detailed information is in dedicated sections, starting from Section 19.4.8: AES basic
chaining modes (ECB, CBC).
Electronic codebook (ECB) mode
Figure 85. ECB encryption and decryption principle
ECB is the simplest mode of operation. There are no chaining operations, and no special
initialization stage. The message is divided into blocks and each block is encrypted or
decrypted separately.
Note: For decryption, a special key scheduling is required before processing the first block.
MSv42140V1
Encryption
Plaintext block 1 Plaintext block 2 Plaintext block 3
Ciphertext block 1 Ciphertext block 2 Ciphertext block 3
Encrypt Encrypt Encrypt
Decryption
key key key
Plaintext block 1 Plaintext block 2 Plaintext block 3
Ciphertext block 1 Ciphertext block 2 Ciphertext block 3
Decrypt Decrypt Decrypt
key key key
input
output
key
scheduling
Legend

ST STM32L0x3 Specifications

General

Brand	ST
Model	STM32L0x3
Category	Microcontrollers
Language	English