Could you please support AES256/CBC/PKCS7Padding?

[VincentChen1212]

HI

This is a good Project.

and
Is this Project Support AES256/CBC/PKCS7Padding ???
or something can reference ??

Thanks

[BruceWind]

Thanx for your issue.
Im going to add some algorithms in few weeks.
I have a lot of plan ,but Im too lazy. sorry.

[BruceWind]

Hi ,man:
i wasn’t lazy today. i made the repo -> https://github.com/BruceWind/CryptoPPInNDK.

some algoritms will soon.

[VincentChen1212]

Hi my Hero,

Many Many Many Many Many Thanks, I Very Need AES256/CBC/PKCS7Padding with C, In all the Github, I can't find any repo

Thanks you again

[BruceWind]

you are welcome!
Im busy this week, i hava a lot of work.Maybe you can to use the repo, and add some algorithms.
write some code to test, then build a so file, and push to device.

Then you can add you code to this repo,build with jni.

[BruceWind]

There is a great article, C++使用AES+Base64算法对文本进行加密,but the algoritm is AES128,isnt 256。

[VincentChen1212]

Hi,

Thanks for your helping.
My Business Model is using AES256/CBC/PKCS7Padding,
And I must use kotlin-native platform to build my project,
it only support c (don't support c++),
so I am so sad to find no suitable project (I don't understand c/c++ )

Thanks You VERY VERY VERY Much

[BruceWind]

I think, no kotlin-native in Android. Only "Java call native" in Android. Java can call native interface,regardless C , C++ or Assembly language.
Do you know I mean?

[BruceWind]

I mean you can use extern "C" to call you C++ code. like this calling-c-dll-from-java.

[VincentChen1212]

Hi,

Thanks for your helping.
My present situation : already create base64/sha/hmac using cinterop in kotlin-native project, now aes256 dosen't implement, but no suitable AES256/CBC/PKCS7Padding using c to reference.

Thanks You very much

[BruceWind]

okay,
this week, i dont have a lot of work, maybe the repo will go ahead a little.

[VincentChen1212]

Hi,
It's a Good news for me.
Thanks for your helping.

My Test Data is:
val data = "Discover interesting projects and people to populate your personal news feed"
val key = "XENT95ZAYCPH2CLFT7M2Y3WEWKB846B8"
val iv = "B3LCLM7CMXLY3ZAF"

The resule is:
JapXrfLPtd5bAkc69VtkeNlUeE/pgYdszgSQoqrDZEmg3GkA6wYx9+JaAtzNRg2ConKHmHtG/gCtNwpyO62OO+Jj+HnsxQwtvm8qkP2hpRI=

You are really my HERO

Thanks you very much

[BruceWind]

I think, maybe you are finding a wrong direction.

Java only provides PKCS#5 padding, but it is the same as PKCS#7 padding. See this question on Crypto.SE:

What is the difference between PKCS#5 padding and PKCS#7 padding

They are interchangeable for the common block ciphers like AES and DES.
And such as AES&DES algorithm in cnblogs.

Then, I wrote a class to test.

import android.util.Base64;

import java.security.spec.AlgorithmParameterSpec;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class AESTest
{

    private static String KEY_AES = "D(G+KbPeShVmYq3t";
    public static String encrypt7(String value) {
        try {
            byte[] key = KEY_AES.getBytes("UTF-8");
            byte[] ivs = KEY_AES.getBytes("UTF-8");
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
            SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
            AlgorithmParameterSpec paramSpec = new IvParameterSpec(ivs);
            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, paramSpec);
            return Base64.encodeToString(cipher.doFinal(value.getBytes("UTF-8")), Base64.DEFAULT);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    public static String encrypt5(String value) {
        try {
            byte[] key = KEY_AES.getBytes("UTF-8");
            byte[] ivs = KEY_AES.getBytes("UTF-8");
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            SecretKeySpec secretKeySpec = new SecretKeySpec(key, "AES");
            AlgorithmParameterSpec paramSpec = new IvParameterSpec(ivs);
            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, paramSpec);
            return Base64.encodeToString(cipher.doFinal(value.getBytes("UTF-8")), Base64.DEFAULT);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}

The result of two function is equal.

Look this: struct padding in crypto++ doc. I think, Crypto++ doesn't support PKCS7Padding.

[VincentChen1212]

Hi,
Thanks for your helping.
I don't understand about C language, so if c only support pkcs5, it is ok.

My test data is use java ＆ C#, my coworker seem also use pkcs5 by java.

You are truly my savior.
I Really need C Code.

Thanks for your helping.