main.cpp

#include <iostream>
#include <string.h>
#include <openssl/rsa.h>
#include <openssl/pem.h>
#include <openssl/err.h>

#include "openssl_rsa.h"

using namespace std;


int main() {

    LOG("OpenSSL_RSA has been started.");
    
    RSA *private_key;
    RSA *public_key;

    char message[KEY_LENGTH / 8] = "Plain text";
    char *encrypt = NULL;
    char *decrypt = NULL;

    RSA *keypair = NULL;
    BIGNUM *bne = NULL;
    int ret = 0;

    char private_key_pem[12] = "private_key";
    char public_key_pem[11]  = "public_key";

    LOG(KEY_LENGTH);
    LOG(PUBLIC_EXPONENT);
    
    // RSA *keypair = RSA_generate_key(KEY_LENGTH, PUBLIC_EXPONENT, NULL, NULL); //Old

    bne = BN_new();
    ret = BN_set_word(bne, PUBLIC_EXPONENT);
    if (ret != 1) {
        // goto free_stuff;
        LOG("An error occurred in BN_set_word() method");
    }
    keypair = RSA_new();
    ret = RSA_generate_key_ex(keypair, KEY_LENGTH, bne, NULL);
    if (ret != 1) {
        // goto free_stuff;
        LOG("An error occurred in RSA_generate_key_ex() method");
    }
    LOG("Generate key has been created.");

    private_key = create_RSA(keypair, PRIVATE_KEY_PEM, private_key_pem);
    LOG("Private key pem file has been created.");

    public_key  = create_RSA(keypair, PUBLIC_KEY_PEM, public_key_pem);
    LOG("Public key pem file has been created.");;

    encrypt = (char*)malloc(RSA_size(public_key));
    int encrypt_length = public_encrypt(strlen(message) + 1, (unsigned char*)message, (unsigned char*)encrypt, public_key, RSA_PKCS1_OAEP_PADDING);
    if(encrypt_length == -1) {
        LOG("An error occurred in public_encrypt() method");
    }
    LOG("Data has been encrypted.");

    create_encrypted_file(encrypt, public_key);
    LOG("Encrypted file has been created.");

    decrypt = (char *)malloc(encrypt_length);
    int decrypt_length = private_decrypt(encrypt_length, (unsigned char*)encrypt, (unsigned char*)decrypt, private_key, RSA_PKCS1_OAEP_PADDING);
    if(decrypt_length == -1) {
        LOG("An error occurred in private_decrypt() method");
    }
    LOG("Data has been decrypted.");

    FILE *decrypted_file = fopen("decrypted_file.txt", "w");
    fwrite(decrypt, sizeof(*decrypt), decrypt_length - 1, decrypted_file);
    fclose(decrypted_file);
    LOG("Decrypted file has been created.");
    
    RSA_free(keypair);
    free(private_key);
    free(public_key);
    free(encrypt);
    free(decrypt);
    BN_free(bne);
    LOG("OpenSSL_RSA has been finished.");

    return 0;
}