#include <iostream>
#include <fstream>
#include <iomanip>
#include <openssl/blowfish.h>
#include <openssl/rand.h>

using namespace std;

void hex_print(unsigned char* mes, int len)
{
	for (int i = 0; i < len; ++i)
		cout << hex << (int)mes[i] << " ";
	cout << endl << endl;
}

int fileCrypt(unsigned char *key, int keyS, unsigned char iv[]) {
	ifstream in("NTL.zip", ifstream::binary);
	if (!in.is_open()) {
		cout << "Error opening in_file\n";
		return 0;
	}
	in.seekg(0, ios::end);
	int plainS = in.tellg();
	//cout << "Az allomany bajt merete: " << std::dec << plainS << endl;

	// a paddingolasi ertek meghatarozasa
	int trunc = plainS % BF_BLOCK;
	int cipherS = plainS + BF_BLOCK - trunc;
	cout << "paddingolt meret: " << cipherS << endl << endl;

	unsigned char *plaintext = new unsigned char[cipherS];
	in.seekg(0, ios::beg);
	in.read((char*)plaintext, plainS);
	in.close();

	//a nyilt szoveg paddingolasa
	if (trunc != 0) {
		for (int i = 0; i < BF_BLOCK - trunc; ++i)
			plaintext[plainS + i] = (BF_BLOCK - trunc) % BF_BLOCK;
	}
	unsigned char *ciphertext = new unsigned char[cipherS];

	// titkositas
	BF_KEY enc_key;
	BF_set_key(&enc_key, keyS, key);
	BF_cbc_encrypt(plaintext, ciphertext, cipherS, &enc_key, iv, BF_ENCRYPT);

	ofstream out("crypt", ofstream::binary);
	if (!out.is_open()) {
		cout << "Error opening out_file\n";
		return 1;
	}
	out.write((char*)ciphertext, cipherS);
	out.close();
}

int fileDecrypt(unsigned char *key, int keyS, unsigned char ivD[]) {

	ifstream in1("crypt", ifstream::binary);
	if (!in1.is_open()) {
		cout << "Error opening in_file\n";
		return 0;
	}
	in1.seekg(0, ios::end);
	int cipherS = in1.tellg();
	//cout << "Az allomany bajt merete: " << std::dec << cipherS << endl;

	unsigned char *ciphertext = new unsigned char[cipherS];
	in1.seekg(0, ios::beg);
	in1.read((char*)ciphertext, cipherS);
	in1.close();

	//visszafejtes
	unsigned char *decryptedtext = new unsigned char[cipherS];

	BF_KEY dec_key;
	BF_set_key(&dec_key, keyS, key);
	BF_cbc_encrypt (ciphertext, decryptedtext, cipherS, &dec_key, ivD, BF_DECRYPT);
	
	ofstream out1("ujNTL.zip", ofstream::binary);
	if (!out1.is_open()) {
		cout << "Error opening out_file\n";
		return 1;
	}
	int plainS = cipherS - decryptedtext[cipherS - 1];
	out1.write((char*)decryptedtext, plainS);
	out1.close();
	return 0;
}

int main()
{
	
	int keyS = 128;
	int temp = keyS / 8;
	
	// kulcs generalas
	unsigned char *key = new unsigned char[temp];
	memset(key, 0, keyS / 8);
	if (!RAND_bytes(key, keyS / 8))
		exit(-1);
	cout << "key:" << endl;
	hex_print(key, keyS/8);
	
	// init vektor generalas
	unsigned char iv[BF_BLOCK], ivD[BF_BLOCK];
	RAND_bytes(iv, BF_BLOCK);
	memcpy(ivD, iv, BF_BLOCK);
	cout << "iv: " << endl;
	hex_print(iv, BF_BLOCK);
	
	fileCrypt(key, keyS, iv);
	fileDecrypt(key, keyS, ivD);
	return 0;
}