Since our life is not only computer, work and programming, for once we leave the digital world to talk a little about music and books.
Playing, listening music and reading books are some of my favourite hobbies. In my free time I enjoy to play piano, listen some electro-swing or read an amazing historic book. But my website did not give enough emphasis on these important parts of my life: for this reason I create two new pages under the new category “More about me”.
I had a little problem to illustrate these two hobbies since I do not have a very definite taste. For example for music I listen rock, classic music, Italian pop, epic metal, Irish music, soundtrack and so on. About books I am not better since I enjoy fantasy, science fiction, historical, politics, detectives stories, thriller…
To solve this bad situation, I recovered two of my favourite social networks: Last.fm and Goodreads. The first one collects all my listened music between a process called “scrobbling”, the second one is a good list of my reading in the past years. By using the available apis and widgets, it was not difficult to obtain two elegant interactive showcases.
As last thing I cannot conclude the section music without showing a little my ability to play piano. For this purpose I embedded two videos with me on the piano.
After all these cryptographic methods I was thinking: maybe this blog is becoming too much serious. I need to give a little of fun to my poor readers.
For this reason I recover from the grave an old program in C that I created in my Bachelor. It was in Italian language, but… Come on! You don’t have to worry! I translate this game in English and I correct some small bugs. So! Have fun!
Eh?!? I didn’t say what about is this program? Really? Oh…
As you can read from the title is “Connect four” on terminal. A simple picture so you can understand better what I am talking.
It is a turn game 1 against 1 where you need to be the first to insert four coins in line horizontally, vertically or diagonally.
In my version you can play against a friend or, if you are alone, against a little smart pc. It is not a very high AI, but it can provide a small challenge.
At the end of every match, a score and the time used will be saved on your pc. In this way you will be able to recover easily the chronology of your matches!
Instructions and rules are also provided inside of the game. You can download it by here.
This week is a cryptographic period and I want to present again AES.
AGAIN?!? Ok… I can understand your concern. Already in the last week I gave you a very similar program in Java. But there was something that bothers me.
When I want to protect something, I want to be able to protect everything. With Java I was quite happy to be able to encrypt any type of language (Chinese, Russian, Italian, Arabic, and so on). But it was not enough for me. I didn’t want only to encrypt simple text files, but even pictures, video or more complicate files.
For this reason I recover an old friend called C and I went brutally on the basis of the file code. To overcome the simple letter structure as ‘A’, ‘b’ or ‘胡’ and transcend in the fantastic world made of zeros and one, i.e. something like this 10101010101.
I am happy thus to make you available a new program in C, downloadable without any problem by here.
Which are the advantages of this version?
+ You can encrypt (and decrypt) any files.
+ It it faster than Java
+ It works fine in Linux too (here the download for Linux version)
Which are the disadvantages?
– The application is not user friendly (you need to use the terminal)
– It is a little harder to select the file that you want to encrypt (or decrypt)
Give a try! But be careful! I will give you the same alert of the last time. If you encrypt a file and you delete the original one (DON’T DO IT), then you can recover your original document only if you own the password. I can’t accept any responsibility or liability for damages arising from the misuse of this program.
Today I want to show a new Java created by myself. It is useful in the case that you want to protect your messages from possible eavesdropper. If you like stories of espionage, the names of Snowden and Wikileaks will not sound new to you. In both the cases the protection or discovery of a secret were the main point of the debate.
When we want to protect our message we are doing “cryptography”.
In general, when we want to protect our message we are doing “cryptography”. At the contrary, if we want to discovery a message (without a password) we are doing “cryptanalysis”. With the java program that you can download from the next link, we are doing “cryptography”.
With this program you will be able to encrypt and decrypt text files (not photos, programs or videos) with one of the most secure method of encryption: AES-256 (or alternatively AES-128 or AES-192).
To create this Java program I used the original paper that the authors, Joan Daemen and Vincent Rijmen, used to propose Rijndael, better known as AES. At this link you can find the original pdf.
For the creation of this program I found two interesting problems: the first one was of mathematical nature. To work with a field with 256 elements, called GF(256), is not simple and required some notion of not trivial algebra. Especially if you don’t understand that he chosen “x” in GF(256) is not a primitive element, but “x+1” it is. Luckily my PhD came to help me, and the creation of a the encryption systems was not really hard for myself. The use of Sage (Python with mathematical steroids) was fundamental to create efficiently this mathematics part. If you don’t understand the problem, don’t worry! And be happy!
The second problem was with the implementation of AES. By having a Chinese wife and being myself Italian, I should use symbols as “我” or “é”. For this reason I should say goodbye to my old friend UTF-8 and say welcome to UTF-16 and its UNICODE world. It was not really challenging, but still interesting.
Give a try! But be careful! If you encrypt a file and you delete the original one (DON’T DO IT), then you can recover your original document only if you own the password. I can’t accept any responsibility or liability for damages arising from the misuse of this program.