Network Security Project 0: Finding the Encrypted Message's Password - Prof. John Black, Assignments of Cryptography and System Security

Download Network Security Project 0: Finding the Encrypted Message's Password - Prof. John Black and more Assignments Cryptography and System Security in PDF only on Docsity! CSCI 6268/TLEN 5831: Network Security Handout P0 CU — John Black October 3, 2007 Project 0 Due Friday, October 19th, in class Problem 1. I have encrypted some message with the following OpenSSL command: % openssl enc -aes128 -base64 < secret-message enter aes-128-cbc encryption password: Verifying - enter aes-128-cbc encryption password: U2FsdGVkX196x5b9Md2JX6D11gTcALXeInqFpRYWBtajOTE9fF0vUa54t6WSjE/Z /Uk7GT3Tfw1eoisEzo7oOyo75AoXh4k6ZInzk0F95DIBkpvE8Es2Mhv87kekrM6s % Your mission is to find the secret message. That sounds impossible, right? I mean, we have encrypted with CBC-AES-128, which is supposed to be virtually unbreakable. BUT, I will tell you that I used a password that is three lowercase letters. In other words, it’s aaa, aab, · · ·, zzz. You must find it. This is simply an exercise in your ability to find a working version of OpenSSL (the simplest solution is to use the CSEL machines, but you could also install it on a home-machine). Then you need to find an efficient way to do a key-search (don’t type them all by hand... write a script or something!). Please turn in: • The password I used • The secret message • The script you used to find the key • Your opinion about the article: should Martin begin training for next year’s competition? You can find a copy of the above ciphertext string on our course web page (so you don’t have to type it in!).