使用Crypto加密大数据的有效方法

我正在寻找使用Crypto加密/解密大文件（一些GB）的解决方案 . 几天前，我正在考虑在this question中使用StringSource，将整个文件读入char数组，然后使用CTR模式对其进行加密/解密 .

将字符串加密为字符串

string  encryptString(string plain, byte key[], int sizeKey, byte iv[], int sizeIV){
    string cipher;
    try{
        CTR_Mode< AES >::Encryption e;
        e.SetKeyWithIV(key, sizeKey, iv, sizeIV);

        StringSource s(plain, true,
            new StreamTransformationFilter(e,
            new StringSink(cipher)
            )
            );

#if 0
        StreamTransformationFilter filter(e);
        filter.Put((const byte*)plain.data(), plain.size());
        filter.MessageEnd();

        const size_t ret = filter.MaxRetrievable();
        cipher.resize(ret);
        filter.Get((byte*)cipher.data(), cipher.size());
#endif
        return cipher;
    }
    catch (const CryptoPP::Exception& e)
    {
        cerr << e.what() << endl;
        return NULL;
    }
}

将字符串解密为字符串

string  decryptString(string cipher, byte key[], int sizeKey, byte iv[], int sizeIV){
    string reco;
    try{
        CTR_Mode< AES >::Decryption d;
        d.SetKeyWithIV(key, sizeKey, iv, sizeIV);

        StringSource s(cipher, true,
            new StreamTransformationFilter(d,
            new StringSink(reco)
            )
            );

#if 0
        StreamTransformationFilter filter(e);
        filter.Put((const byte*)plain.data(), plain.size());
        filter.MessageEnd();

        const size_t ret = filter.MaxRetrievable();
        cipher.resize(ret);
        filter.Get((byte*)cipher.data(), cipher.size());
#endif
        return reco;
    }
    catch (const CryptoPP::Exception& e)
    {
        cerr << e.what() << endl;
        return reco;
    }
}

将加密字符串包装在上面

char* encrypt(char * plainText, byte key[], int sizeKey, byte iv[], int sizeIV, long len){
    string ss(plainText, len);
    long lengSS = ss.length();

    string cipher = encryptString(ss, key, sizeKey, iv, sizeIV);
    len = cipher.size();
    char * writable = new  char[len];
    std::copy(cipher.begin(), cipher.end(), writable);
    writable[len] = '\0';
    return writable;
}

将上面的解密字符串换行

char* decrypt(char * cipher, byte key[], int sizeKey, byte iv[], int sizeIV, long len){
    string ss(cipher, len);
    long lengSS = ss.length();
    string recovered = decryptString(ss, key, sizeKey, iv, sizeIV);
    //FileUtil::writeStringToFile("d2.txt", recovered);
    char * writable = new char[recovered.size() ];
    std::copy(recovered.begin(), recovered.end(), writable);
    writable[recovered.size() ] = '\0';
    return writable;
}

主要的

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

    byte key[AES::DEFAULT_KEYLENGTH] = { '1', '2', '3', '4', '5', '6', '7', '8', '1', '2', '3', '4', '5', '6', '7', '8' };
    byte iv[AES::BLOCKSIZE] = { '8', '7', '6', '5', '4', '3', '2', '1', '8', '7', '6', '5', '4', '3', '2', '1' };
    //prng.GenerateBlock(iv, sizeof(iv));
    char* pdata = "CTR encrypt mode 1234567890";
    char * sourceFileName = "1MB.txt";
    char * targetFileName = "1MB.aes.crpp.txt";

    /*
    Looking for parameters.
    param 0: e to encrypt. d to decrypt
    param 1: sourceFileName
    param 2: targetFileName
    */
    if (argc > 1){

        char * action = argv[1];
        sourceFileName = argv[2];
        targetFileName = argv[3];
        long size = 0;

        char * pdata = FileUtil::readAllByte(sourceFileName, size);

        string ext = getExtension(sourceFileName);

        char * result1 = NULL;
        if (strcmp(action, "e") == 0){
            result1 = encrypt(pdata, key, sizeof(key), iv, sizeof(iv), size);
        }
        else if (strcmp(action, "d") == 0){
            result1 = decrypt(pdata, key, sizeof(key), iv, sizeof(iv), size);
        }
        FileUtil::writeFile(targetFileName, result1, size);
        //FileUtil::writeStringToFile(targetFileName, recovered1);
    }
    else{
        cout << "Missing/Invalid params" << endl;

    }
    return 0;

}

现在这个解决方案可以加密/解密文件，大小可达几百MB . 但是当我使用1GB文本文件时，它有错误：

Unhandled exception at 0x74DFA6F2 in AES-CRPP.exe: Microsoft C++ exception: std::bad_alloc at memory location 0x00AFE480.

在线：

char*encrypt(...){
string ss(data, len)
...
}

我有8GB的RAM，它看起来像读取1GB的char并将其转换为字符串导致错误 . 在另一个question中，jww给了我一个底部的提示，但我无法使它工作 . 是否有使用Crypto进行大字节（char）数组加密的解决方案

关于在这里使用FileSource文档：enter link description here代码示例：

EAX< Blowfish >::Encryption e1;
        e1.SetKeyWithIV(key, key.size(), iv, sizeof(iv));

        CryptoPP::FileSource fs1(ofilename.c_str(), true,
            new AuthenticatedEncryptionFilter(e1,
            new FileSink(efilename.c_str())
            ));



        EAX< Blowfish >::Decryption d2;
        d2.SetKeyWithIV(key, key.size(), iv, sizeof(iv));

        CryptoPP::FileSource fs2(efilename.c_str(), true,
            new AuthenticatedDecryptionFilter(d2,
            new FileSink(rfilename.c_str()),
            AuthenticatedDecryptionFilter::THROW_EXCEPTION
            ));

它不允许我将输出密码导出到temporatory char *变量，而不是直接保存到文件 . 当然我可以等待文件加密完成，然后再将输出文件读入内存，但它看起来很糟糕 .