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AES encryptionPlease write a program to perform the first round of

AES encryptionPlease write a program to perform the first round of

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AES encryption

Please write a program to perform the first round of AES

encryption using a 128-bit key. The inputs are a 128-bit

plaintext and a 128-bit key. Your code is to perform the

following steps, as taken from the pseudo-code found on

page 15 of the FIPS-197 document: AddRoundKey(state,

key) In this code state is the 16-byte plaintext (as it is

modified) and key is the 16-byte key. Test your program on

the inputs found in Appendix B of the FIPS-197 document

(page 33).

Looking at that, here is what should be in the state array

after each step:

AddRoundKey(state, key): 19 a0 9a e9 3d f4 c6 f8 e3 e2

8d 48 be 2b 2a 08

SubBytes(state): d4 e0 b8 1e 27 bf b4 41 11 98 5d 52 ae

f1 e5 30

ShiftRows(state): d4 e0 b8 1e bf b4 41 27 5d 52 11 98 30

ae f1 e5

MixColumns(state): 04 e0 48 28 66 cb f8 06 81 19 d3 26

e5 9a 7a 4c

The input should be two strings, each containing 32

hexadecimal characters. The first one should be the key

and the second the plaintext.

Test your program on the input pair:

2b7e151628aed2a6abf7158809cf4f3c

3243f6a8885a308d313198a2e0370734

**if anyone can help me with this I would really appreciate

it. I have tried numerous times and I cannot seem to get in

right. Thanks!! If this code could also be in Java because

that is what I understand the most I would appreciate it.

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Solution

I have used the AES algorithm to design this program.

Instead of making user input the key, I have proceeded

through the randon generation of the key to encrypt the the

iput text and after that to decrypt it.

This algorithm uses the PKCS5 padding to create the

cipher text.

Below is the algorithm class and the main class to

demonstrate the example.

import javax.crypto.BadPaddingException;

import javax.crypto.spec.IvParameterSpec;

import javax.crypto.Cipher;

import javax.crypto.IllegalBlockSizeException;

import javax.crypto.KeyGenerator;

import java.io.UnsupportedEncodingException;

import java.security.InvalidAlgorithmParameterException;

import java.security.SecureRandom;

import java.util.logging.Level;

import java.util.logging.Logger;

import javax.crypto.NoSuchPaddingException;

import javax.crypto.SecretKey;

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AES encryption Please write a program to perform the first round of AES encryption using a 128-bit key. The inputs are a 128-bit plaintext and a 128-bit key. Your code is to perform the following steps, as taken from the pseudo -code found on page 15 of the FIPS-197 document: AddRoundKey(state, key) In this code state is the 16 -byte plaintext (as it is modified) and key is the 16-byte key. Test your program on the inputs found in Appendix B of the FIPS -197 document (page 33). Looking at that, here is what should be in the state array after each step: AddRoundKey(state, key): 19 a0 9a e9 3d f4 c6 f8 e3 e2 8d 48 be 2b 2a 08 SubBytes(state): d4 e0 b8 1e 27 bf b4 41 11 98 5d 52 ae f1 e5 30 ShiftRows(state): d4 e0 b8 1e bf b4 41 27 5d 52 11 98 30 ae f1 e5 MixColumns(state): 04 e0 48 28 66 cb f8 06 81 19 d3 26 e5 9a 7a 4c The input should be two strings, each containing 32 hexadecimal characters. The first one should be the key and the second the plaintext. Test your program on the input pair: 2b7e151628aed2a6abf7158809cf4f3c 3243f6a8885a308d313198a2e0370734 **if anyone can help me with this I would really appreciate it. I have tried numerous times and I cannot seem to get in right. Thanks!! If this code could also be in Java because that is what I understand the most I would appreciate it. Solution I have used the AES algorithm to design this program. Instead of making user input the key, I have proceeded through the randon generation of the key to encrypt the the iput text a ...
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