Cryptographic processor (CRYP)
RM0090
724/1731
DocID018909 Rev 11
illustrate AES-CTR encryption and decryption, respectively.
Figure 226. AES-CTR mode encryption
1. K: key; C: cipher text; I: input Block; o: output block; Ps: plain text before swapping (when decoding) or
after swapping (when encoding); Cs: cipher text after swapping (when decoding) or before swapping (when
encoding); P: plain text; IV: Initialization vectors.
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!%!ENCRYPT
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CIPHERTEXT#
SWAPPING
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'$7$7<3(
+
OR
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