CTR-AES128, CTR-AES192, and CTR-AES256 modes are supported in this implementation.
Attention
The bit-width of the interfaces provided is shown as follows:
| plaintext | ciphertext | cipherkey | IV | |
| CTR-AES128 | 128 | 128 | 128 | 128 |
| CTR-AES192 | 128 | 128 | 192 | 128 |
| CTR-AES256 | 128 | 128 | 256 | 128 |
The algorithm flow chart is shown as follows:
As seen from the chart, both encryption and decryption parts of CTR mode have no dependencies, so the input block of each iteration can be directly calculated by the counter. Thus, both encryption and decryption part of CTR mode can achieve an initiation interval (II) = 1.