SPRUJB6B November 2024 – May 2025 AM2612
Figure 7-103 CFB128 Feedback ModeFigure 7-103 illustrates the full block (128-bit) Cipher Feedback (CFB) mode of operation for both encryption and decryption. The input for the crypto core is the IV; the result is XOR-ed with the data. The result is fed back via the IV register, as the next input for the crypto core. The decrypt operation is reversed, but the crypto core is still performing an encryption.