Eu preciso de um exemplo de criptografia de string (em C ++ -> estou trabalhando no linux-Ubuntu) com aes-cbc256 e um preenchimento: PKCS7 Por favor, ajude.

Para o código a seguir, como posso definir o IV como 0 e definir o valor da chave como um valor de sequência? Eu também gostaria de adicionar o preenchimento pkcs7. Estou usando a criptografia ++ lib (no Linux)

// Driver.cpp   
//      

#include "stdafx.h"    
#include "cryptopp/dll.h"    
#include "cryptopp/default.h"    
#include "crypto++/osrng.h"    
using CryptoPP::AutoSeededRandomPool;    

#include <iostream>    
using std::cout;    
using std::cerr;       

#include <string>    
using std::string;       

#include "crypto++/cryptlib.h"    
using CryptoPP::Exception;        

#include "crypto++/hex.h"    
using CryptoPP::HexEncoder;    
using CryptoPP::HexDecoder;        

#include "crypto++/filters.h"    
using CryptoPP::StringSink;    
using CryptoPP::StringSource;    
using CryptoPP::StreamTransformationFilter;        

#include "crypto++/aes.h"    
using CryptoPP::AES;       

#include "crypto++/ccm.h"    
using CryptoPP::CBC_Mode;       

#include "assert.h"        

int main(int argc, char* argv[])    
{    
    AutoSeededRandomPool prng;        

    byte key[ AES::DEFAULT_KEYLENGTH ];    
    prng.GenerateBlock( key, sizeof(key) );        

    byte iv[ AES::BLOCKSIZE];    
    iv[AES::BLOCKSIZE] = 0;    
    //prng.GenerateBlock(iv,  sizeof(iv) );        

    string plain = "CBC Mode Test";    
    string cipher, encoded, recovered;       

    // Pretty print key    
    encoded.clear();    
    StringSource( key, sizeof(key), true,    
                  new HexEncoder(new StringSink( encoded )) // HexEncoder    
    ); // StringSource

    cout << "key: " << encoded << endl;        

    // Pretty print iv    
    encoded.clear();

    StringSource( iv, sizeof(iv), true,    
        new HexEncoder(new StringSink( encoded )) // HexEncoder    
    ); // StringSource

    cout << "iv: " << encoded << endl;       

    /*********************************\
    \*********************************/

    try    
    {    
        cout << "plain text: " << plain << endl;            
        CBC_Mode< AES >::Encryption e;    
        e.SetKeyWithIV( key, sizeof(key), iv );     

        // The StreamTransformationFilter adds padding    
        //  as required. ECB and CBC Mode must be padded    
        //  to the block size of the cipher.    
        StringSource( plain, true,     
            new StreamTransformationFilter( e,    
                new StringSink( cipher )    
            ) // StreamTransformationFilter          
        ); // StringSource    
    }    
    catch( CryptoPP::Exception& e )    
    {    
        cerr << "Caught Exception..." << endl;    
        cerr << e.what() << endl;    
        cerr << endl;    
    }    

    /*********************************\    
    \*********************************/    

    // Pretty print    
    encoded.clear();    
    StringSource( cipher, true,    
        new HexEncoder(    
            new StringSink( encoded )    
        ) // HexEncoder    
    ); // StringSource    
    cout << "cipher text: " << encoded << endl;    

    /*********************************\    
    \*********************************/    

    try    
    {    
        CBC_Mode< AES >::Decryption d;    
        d.SetKeyWithIV( key, sizeof(key), iv );    

        // The StreamTransformationFilter removes    
        //  padding as required.    
        StringSource s( cipher, true,     
            new StreamTransformationFilter( d,    
                new StringSink( recovered )    
            ) // StreamTransformationFilter    
        ); // StringSource    

        cout << "recovered text: " << recovered << endl;    
    }    
    catch( CryptoPP::Exception& e )    
    {    
        cerr << "Caught Exception..." << endl;    
        cerr << e.what() << endl;    
        cerr << endl;    
    }    

    /*********************************\    
    \*********************************/    

    assert( plain == recovered );    

    return 0;    
}