I’m putting up the last cryptographic algorithm I implemented in Java. It’s the winner of AES contest, providing high security and good speed.
It is called Rijndael or more commonly AES. I wont bother you with details anymore. For any references wikipedia is your friend.
Here is the wikipedia article about it, and more helpful check out the external links for a complete description of the algorithm.
Apart from the others I talked about, AES uses pretty advanced mathematical operations in the Galois Field.
Sorry for the lack of comments in the source code I’m putting below, but functions names are pretty descriptive and you should be able to pick it up if you go through it having some AES description document at hand. Call me lazy…that’s the truth 🙂
I’ve also put together an Eclipse project including all algorithms I’ve discussed, with some test cases.
N3vrax's Blog 
wonderful!!!!
Thank You very much man!
Thanks for the AES algorithm. I need to back level some code to jdk 1.4 and it does not have the cipher which came in 1.6 (I believe). However when testing the decryption algorithm I did find a bug. It was dropping the last character of the decrypted byte array in the deletePadding() method. I corrected this by removing the -1 in the following line of code:
byte[] tmp = new byte[input.length – count – 1];
Thanks again!
No problem.
Thanks you pointed it out.
I’ll check and repair it when I’ll have time.
Excellent AES algorithm for compatibility with C code supplied by NXP for LPC1769
Really great – thank you very much!
Thanks 🙂
Helped me with a delayed-to-the-last-minute project.
hellow can you please help me with the AES algorithm file or the whole project of algorithms in netbean will really appreciate my email is fwamon@gmail.com
Guyz, can any1 tell me how to run this AES implementation in eclipse……. cuz wen i tried to execute the code in eclipse it gave me an error sayin “selection does not contain a main type”
thnxx in advance:)
Hi,
There’s a full eclipse project uploaded. You can find it on the AES article.
It contains all algorithms along with some test cases.
Hope it helps.
yess, was of very much help…
wonderfull blog here..
thanx again 🙂
can u please tell, how you got the successful run
check out the eclipse project in one of my other posts. It contains test cases for all algorithms implemented
i just started to learn AES code.. i try to RUN the code in eclipse.. but it cannot RUN.. and there are error. what should i do..
the full eclipse project found on the AES post should run without error.
Search for the error you receive, in case the above is not working. I cannot help you without seeing the error.
Ok its working. It was my mistake. I have got the output. I try to change the Text clar but it will be error. Is it possible for me to change the input? One more question, where can i learn basic of AES Algorithm. I need to do study project with it. But actually i am zero about the AES. Thank You. I really appreciate your help, sir.
Text clar: CRIPTEAZA ASTA
Text criptat poligramic: ABCGIPE APSRWJ
Text anterior descifrat: CRIPTEAZA ASTA
im sorry, i need to ask some questions,
(1) What is actually String K stand for? Is it a KEY? Is it possible for me to change it?
(2) What is mean by “Text criptat” ? Is it a cipher text?
(3) Then lastly, actually i try to put another string then the criptat value is something like this:
Enter Text:
zakirin
Text clar: zakirin
Text criptat AES: ñµJ-ùì^“?ŸèUõ
Text decriptat AES: zakirin
——————
my question is, why criptat is not in numbering mode? Please help me to understand this. Thank You. I really need help in this encryption.
yes, k is the key.
text criptat is the encrypted text.
thanks for the info
thankyou so much…it really helped!!
hey there pls can u tell me hw u ran the code
hey ok i got hw to run d code but i wanna give different input and test aes alone..cud u help me with an idea pls asap ?
Can you please tell me what additional steps do i have to add if i want to extend the the algorithm to 128-bits encryption?
As I recall, my example already uses 128 bits encryption – both bloc size and key size.
Perhaps you want to extend it to greater key lengths. The process stays almost the same, you’ll need to change some constants. Reading AES specs might help(try wikipedia).
can u plz explain this code 😀 😛 😉
Sry…there’s too much theory involved. Would be best if you follow the code along with official AES specification.
i got the right output
enter the plain text
abcdefgh123456789
enter the key
12345hello
the encrypted text is:
Ѐ
ø
Ç ÎÓ 4×Éïù¤¶«Š¿¨¦ÎæÂWe.
the decrypted text is:
abcdefgh123456789
could you please explain the format of encrypted text. do these symbols belong to ascii or something else?? please reply
great codes. I want to know. How you develop the permutation array in code of polygram.
if you are referring to polygram substitution cipher, it a simple one. It substitutes block of characters(2 in my case) with another block. So I generate a matrix with all possible combinations of 2 chars, than mix it up with some permutation array. This can be anything. It just tells what indices will get permuted. Do this several times until the initial matrix looks random. Than taking 2 chars from plain text, substitute it with the chars found at column/row intersection of the substitution matrix.
Thank you for shared code. I copypasted it in my current project for j2me (yes i know it is obsolete) platform which has lack of any crypto api.
any suggestion what can i do to speed up AES encryption? tq
is there any limit of character for text input and key? i noticed that key cannot be lower than 3 character. why the key should be more than three character? is it because of 128 bit? tq
there is not limit on the input text. The key lenght is fixed – 128 bits for example or up to 256 for AES
ok thanks for the information and the codes
With the source code that have all classes listed, there is no Galois Field, if there is in what class should i find it. I found codes about it but written in C. Here is what i need to do:
Write a program that can serve as a four function calculator for carrying out the arithmetic operations (+, −, ×,and ÷) on the polynomials that belong to the finite field GF(28) using the irreducible polynomial m(x) = x8 + x4 + x3 + x + 1. When started, your script should place the user in an interactive mode and wait for the user to enter expressions for evaluation. Your script should prompt the user for three items:
1) a bitstring that would serve as the first operand;
2) another bitstring that would serve as the second operand; and, finally,
3) the operator to be used. The bits in each input bit pattern supplied by the user would stand for the respective polynomial coefficients. The program should output a bitstring that is the result of the operation.
Any Help will be greatly appreciated.
Can you explain algoritm code in “generateSubkey()”? i still confused
i want to ask you about RC-6 encryption, can i have your e-mail, please?
thank you
Thanks you lot! Very good implementation!
I spent some time trying to find out which initialization parameters (key size, mode, padding) are used by this implementation of AES. These parameters are needed when you want to decipher a message ciphered by this implementation in other system which has other implementation of the algorithm.
I want to share a result of my investigation with others to save their time.
This is key facts:
* Algorithm: AES
* Key size: 128 bits
* Mode: ECB
* Padding: no padding
Code snippet to decipher a message by implementation of AES in standard JDK:
byte[] encrypted = ….; // replace by your actual crypted message
byte[] bkey = “0123456789abcdef”.getBytes(“UTF-8”); // replace by your key (must be 16 byte)
SecretKeySpec sks = new SecretKeySpec(bkey, “AES”);
Cipher jdkCipher = Cipher.getInstance(“AES/ECB/NoPadding”);
jdkCipher.init(Cipher.DECRYPT_MODE, sks);
byte[] decrypted = jdkCipher.doFinal(encrypted);
// This is not the end of our story.
// Because we didn’t use padding we must remove trailing zeros in the variable ‘decrypted’.
// See method AES#deletePadding(…) as example how that can be done.
Can you explain FFMul?
it’s possible to implement a function to read from two files: one with the crypt text and the other with the key and decrypt the contain of the text?
Hi, could u help me please, when i run the codes, nothing appear. do i need to set something before run?
i need blowfish algo code for image encryption and decryption in java. plzz send code on my mail..
ok guys don’t bite me but i haven’t used eclipse b4 so i don’t knw hw to import the code and i tried using netbeans which am perfect in but it seems dey ain’t compartible
ty for ur info dude,
can i use this code to encrypt other file type?
thanks for code, I have some question. For example, in function “encryptbloc()” state is array byte[][] state = new byte[4][Nb]; but you wrote state = AddRoundKey(state, w, 0); why it was not fault.Thanks
WHY the encrypted text isn’t in hexadicimale “ie number or alphabique”
why they are in the text en crypted ” # !,?
and the six of key is 128 or 256 please tell me
Text clar: hello world!
Text criptat AES: $¤Q47jIÖ·ô]†¶-
Text decriptat AES: hello world!
——————
// why Text criptat AES is like this?
String k = “4B66453BBBEDEF81E30B62BDE35F204F”;
what is nb, nr, nk?
where is the input statement?
this file does not have main method?
how can i run it?
If you need more details about AES you can try and find this book “The Laws of Cryptography with Java Code” by Neal R. Wagner.
hello, can you upload “Eclipse project with all algorithms” again please? because this link isn’t working. regards!
To all of you asking the programmer to upload his “sc” work. If your school is Cleveland state University do not use the code as my professor knew the guy who wrote this code. So he sais, reverse engineering it and try to solve it by adding ur own work.
Thank to the dude or dudette that help me 5 yrs ago.
This is only for csu students and that one Indian kid that like to cheat.
so there is no option? I’m not a csu student but now I’m working on similar project on my uni. I think we should help ech other. regards!
You are so right. We are not reinventing the wheel if anything we making it better.
Can you upload again MARS java source?
really helpful if i could get the source code for AES , Can you please send me the code as i am working in it for my research work.
thank you
Sorry for the links, dropbox changed that. Updated with new links.
Hope code would help, and sorry all of you, but I don’t really keep this blog alive. Maybe I’ll open a new one someday.
Hello, could you add an implementation of “Lucifer” block cipher too? Thanks!
Hi,
Do you also have the AES implementation of CBC, CFB, OFB modes?
Thanks,
Sitra
Hi,
I tried to use same key to encrypt same plain text on oracle database (by DBMS_CRYPTO) and JAVA (by import javax.crypto.Cipher). And I can get the same cipher text. But I do it same way on your AES code, the cipher text is different. So is there any problems for your code? I need to use the source code for AES encryption but I cant find the right version.
Thank you.
thanks for the project, but the link is unreachble