Question 1
Write a program to attack the Textbook RSA Encryption Scheme in order to decrypt the encrypted file key_enc.txt which contains the 128 bits AES secret key together with the initialisation vector (IV) for Question 2. You must explain and show how the attack is done. The RSA parameters are as follows:
N:
1138962637897276378307938215512222422011139335076573193725344875540991426121023228370271274859600271357256043587631029100558245044301219258717020849299280196120
04430128052142748893012310578687183850021947167608503022583720901965948811803799200406402065090559755858489087278843248937684896701137338262162804639
e: 65537
The RSA.class will read in the ciphertext stored inside key_enc.txt and decrypt it to the original plaintext. When you run the class file, make sure it is placed in the same directory with the text file.
If you get java.lang.UnsupportedClassVersionError, update your jre and jdk to the latest version. Also, make sure you run the class file with the -Dfile.encoding=UTF-8 parameter.
Question 2
Decrypt the file Q2_encrypted with AES in CBC mode with PKCS5 padding scheme. Explain how to execute the decrypted file.
Assessment Scheme
1. Report
a. Formatting & Grammar
b. Question 1 - (At most will be given, if you don't perform cryptanalysis)
i. Explanation of the attack
ii. Successful decryption
c. Question 2
i. Parameters setup
ii. Read ciphertext
iii. Decrypt file
2. Make sure your report is original or 10 marks will be deducted regardless your total marks.