Cryptography: This question concerns block cipher padding. Suppose the block cipher has a block size of $16$ bytes. A certain message ends with a partial block which is $4$ bytes. We must reversibly pad out the message to use some block cipher modes, such as CBC $($even if the last block is full$).$

Consider the following padding strategy.

Append a single byte with value $128,$ and then as many zero bytes as required to make the overall length a multiple of $16.$

Suppose the final $($possibly partial$)$ block of the message is $"0$x$00010203"$ in hexadecimal. Write out the complete final block in hexadecimal. Please do not put a leading $0$x as this has been written already.cryptography