I realized that #encryption is not easy. Adjusted my goal from building a full blown Rijndael #cipher to a more simple xor block cipher. For educational purposes only!

Now I am more or less ready with the #base64 encoding of the input (#plaintext and #key), conversion to #ASCII #hex and then creating #binary codes. Then the plaintext has to be split into 16 byte blocks, which are to be #xor-ed with the key.

Todo: key-rotation, to make the algorithm stronger.

Today I learned: all the above. But especially how valuable base64 encoding is for converting non-ASCII characters.