This function adds the round key to state. The round key is added to the state by an XOR function.

Cipher is the main function that encrypts the PlainText.

MixColumns function mixes the columns of the state matrix. The method used to multiply may be difficult to understand for the inexperienced. Please us

The SubBytes Function Substitutes the values in the state matrix with values in an S-box.

MixColumns function mixes the columns of the state matrix optimized!!

The ShiftRows() function shifts the rows in the state to the left. Each row is shifted with different offset. Offset = Row number. So the first row is

The SubBytes Function Substitutes the values in the state matrix with values in an S-box.

OFB and CTR are symmetric (encrypt == decrypt). A single implementation is shared by encode() and decode() to avoid duplication and divergence.