#include <iostream>

#include <crypto++/osrng.h>  //needed for AutoSeededRandomPool
#include <crypto++/modes.h>
#include <crypto++/blowfish.h>
#include <crypto++/filters.h>

using namespace std;
using namespace CryptoPP;  //the general crapto++ namespace

int main() {
		
    AutoSeededRandomPool rng;
    string key(Blowfish::DEFAULT_KEYLENGTH, 0);
    string iv(Blowfish::BLOCKSIZE, 0);// this is the Initialization Vecktor

  //Create a random key as well as a random IV with default sizes (16)
    rng.GenerateBlock((unsigned char*)key.c_str(), Blowfish::DEFAULT_KEYLENGTH);
    rng.GenerateBlock((unsigned char*)iv.c_str(), Blowfish::BLOCKSIZE);
		
    string plain = "This string will be encrypted throug Blowfish!";
    string encrypted;  //will store the encrypted string
    string decrypted;  //will store the string after it is decrypted again

  //Setup the Blowfish Cipher in CBC-Mode
    Blowfish::Encryption blowEn((unsigned char*)key.c_str(), key.size());
    CBC_Mode_ExternalCipher::Encryption cbcEn( blowEn, (unsigned char*)iv.c_str() );

  //Put the "plain" string into the cipher and encrypt it to "encrypted
    StreamTransformationFilter stfEncryptor(cbcEn, new StringSink( encrypted ) );
    stfEncryptor.Put( (unsigned char*)plain.c_str(), plain.size() + 1 );
    stfEncryptor.MessageEnd();

  // Decrypt (very analog to the encryption block
    Blowfish::Decryption blowDe((unsigned char*)key.c_str(), key.size());
    CBC_Mode_ExternalCipher::Decryption cbcDe( blowDe, (unsigned char*)iv.c_str() );

    StreamTransformationFilter stfDecryptor(cbcDe, new StringSink( decrypted ) );
    stfDecryptor.Put((unsigned char*)encrypted.c_str(), encrypted.size() );
    stfDecryptor.MessageEnd();

  //Dump "plain"
    cout << "Plain: "<< endl << plain << endl << endl;

  //Dump "encrypted" (convert it to hexadecimal numbers for better reading)
    cout << "Encrypted text: " << endl;
    for( int i = 0; i < encrypted.size(); i++ ) {
        cout << hex << (0xff & (int)encrypted[i]) << " ";
    }

    cout << endl << endl;

  // Dump Decrypted Text
    cout << "Decrypted Text: " << endl;
    cout << decrypted;
    cout << endl << endl << ":-)" << endl;

    return 0;
}

19:06 aluser@alf:/tmp$ echo "super secret contents" > file.txt
19:06 aluser@alf:/tmp$ tar cf - file.txt | gpg -e -o encryptedfile1.gpg -r my@email.address && rm file.txt
19:06 aluser@alf:/tmp$ gpg -d encryptedfile1.gpg | tar xf -
[ type your passphrase ]
19:07 aluser@alf:/tmp$ cat file.txt
super secret contents

g++ -lcryptopp sourceFile.cpp

cd /usr
find -name blowfish.h

#include <crypto++/blowfish.h>

#include "/no/default/includes/cryptopp/blowfish.h"

#include <cryptopp/blowfish.h>

g++ -lcryptopp -I/no/default/includes sourceFile.cpp

#include <fstream>
#include <iostream>
//cryptopp libraries
#include <cryptopp/osrng.h>  //needed for AutoSeededRandomPool
#include <cryptopp/modes.h>
#include <cryptopp/blowfish.h>
#include <cryptopp/filters.h>

using namespace std;
using namespace CryptoPP;

int main()
{
 int choice;
 cout<<"//////////////////////////////"<<endl;
 cout<<"1 copy file with new encrypted filename\n2 rename file\n3 rename with filename encryption/decryption"<<endl;
 cout<<"CTRL+C to exit"<<endl;
 cout<<"//////////////////////////////"<<endl;
 cin>>choice;
 //RENAME WITH A NEWLY CHOSEN FILENAME
 if (choice==1)
 {
  string infilename;
  string outfilename;
  cout <<"Enter input filename: ";
  cin >>infilename;
  ifstream input(infilename.c_str());
  cout <<"Enter output filename: ";
  cin >>outfilename;
  ofstream output(outfilename.c_str());
  char c;
  while (!input.eof()) 
   {
    input.get(c);
    output << c;
   }
 }
 //RENAME TO DEFAULT NAME
 if (choice==2)
 {
  string infilename;
  cout <<"Enter input filename: ";
  cin >>infilename;
  ifstream input(infilename.c_str());
  rename(infilename.c_str(),"nuovofile");
 }
 //ENCRYPT FILENAME
  if (choice==3)
 {
  string infilename;
  string outfilename;
  cout <<"Enter filename of file to encrypt or decrypt: ";
  cout<<"\n";
  cin >>infilename;
  cout<<"\n";
  ifstream input(infilename.c_str());
  
  AutoSeededRandomPool rng;
  string key(Blowfish::DEFAULT_KEYLENGTH, 0);
  string iv(Blowfish::BLOCKSIZE, 0);// this is the Initialization Vecktor
  
  cout<<"enter the password..(12 charachters max)"<<endl;
  cout<<"\n";
  cin>>key;
  iv="àc€*Õ=Xòžy"; //default block
  
  cout<<"Do you want to encrypt 1 \nor to decrypt 0 \n?";
  int choice;
  cin>>choice;
  if (choice)
  {
   //Setup the Blowfish Cipher in CBC-Mode
   Blowfish::Encryption blowEn((unsigned char*)key.c_str(), key.size());
   CBC_Mode_ExternalCipher::Encryption cbcEn( blowEn, (unsigned char*)iv.c_str() );

   //Put the "plain" string into the cipher and encrypt it to "encrypted
   StreamTransformationFilter stfEncryptor(cbcEn, new StringSink( outfilename ) );
   stfEncryptor.Put( (unsigned char*)infilename.c_str(), infilename.size() + 1 );
   stfEncryptor.MessageEnd();
  
  }
  else
  {
     // Decrypt (very analog to the encryption block
    Blowfish::Decryption blowDe((unsigned char*)key.c_str(), key.size());
    CBC_Mode_ExternalCipher::Decryption cbcDe( blowDe, (unsigned char*)iv.c_str() );

    StreamTransformationFilter stfDecryptor(cbcDe, new StringSink( outfilename ) );
    stfDecryptor.Put((unsigned char*)infilename.c_str(), infilename.size() );
    stfDecryptor.MessageEnd();
  }
  cout<<"renaming to..."<<outfilename<<endl;
  rename(infilename.c_str(),outfilename.c_str());
 }
}