This question concerns block cipher padding. Suppose the block cipher has a block size of 17 bytes. A certain message ends with a partial block which is 15 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 17. Suppose the final (possibly partial) block of the message is "0x000102030405060708090a0b0c0d0e" in hexadecimal. Write out the complete final block in hexadecimal. Please do not put a leading Ox as this has been written already. Ox

This question concerns block cipher padding. Suppose the block cipher has a block size of 17 bytes. A certain message ends with a partial block which is 15 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 17. Suppose the final (possibly partial) block of the message is "0x000102030405060708090a0b0c0d0e" in hexadecimal. Write out the complete final block in hexadecimal. Please do not put a leading Ox as this has been written already. Ox

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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