encryption.cpp

#include "encryption.h"
#include <openssl/sha.h>
#include <openssl/aes.h>
#include <openssl/md5.h>
#include <string>
#include <iostream>
#include <sstream>
#include <iomanip>
#include <fstream>
#include <random>
#include "simplecrypt.h"

random_device my_random_device;
default_random_engine my_random_engine(my_random_device());

QString crypt::gen_salt() {

    const char charset[] =
        "0123456789"
        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
        "abcdefghijklmnopqrstuvwxyz"
        "!$%^&():'><,|";

    uniform_int_distribution<int> random_number(0, sizeof(charset) - 2);

    QString salt;
    salt.reserve(SHA256_DIGEST_LENGTH);
    for( int i = 0; i < SHA256_DIGEST_LENGTH; i++ ) {
        salt.push_back(charset[random_number(my_random_engine)]);
    }
    return salt;
}

QString crypt::buffer_as_hex(const unsigned char *buf, size_t size) {
    stringstream res;
    res << hex << setfill('0');
    for( size_t i = 0; i < size; ++i )
    {
        res << setw(2) << static_cast<unsigned int>(buf[i]);
    }
    return QString::fromStdString(res.str());
}

QString crypt::encrypt(QString decrypted, QString pass) {
    quint64 key{1};
    key = static_cast<quint64>(pass.toULongLong());
    SimpleCrypt crypto(key);
    return crypto.encryptToString(decrypted);
}

QString crypt::decrypt(QString encrypted, QString pass) {
    quint64 key{1};
    key = static_cast<quint64>(pass.toULongLong());
    SimpleCrypt crypto(key);
    return crypto.decryptToString(encrypted);
}

QString crypt::sha256(const QString pass) {
    const string str = pass.toLocal8Bit().constData();
    unsigned char hash[SHA256_DIGEST_LENGTH];
    SHA256_CTX sha256;
    SHA256_Init(&sha256);
    SHA256_Update(&sha256, str.c_str(), str.size());
    SHA256_Final(hash, &sha256);
    return buffer_as_hex(hash, SHA256_DIGEST_LENGTH);
}

QString crypt::md5(const QString pass) {
    const string str = pass.toLocal8Bit().constData();
    unsigned char hash[MD5_DIGEST_LENGTH];
    MD5_CTX md5;
    MD5_Init(&md5);
    MD5_Update(&md5, str.c_str(), str.size());
    MD5_Final(hash, &md5);
    stringstream ss;
    return buffer_as_hex(hash, MD5_DIGEST_LENGTH);
}