Question

我正在尝试使用crypto++中的aes算法加密和解密纯文本

这是我的加密方法

/*
 * Encrypt the given text
 */

template<typename T>
T encryptText(T plainText) {
    /* Key and IV setup
     * AES encryption uses a secret key of a variable length (128-bit, 196-bit or 256-   
     * bit). This key is secretly exchanged between two parties before communication   
     * begins. DEFAULT_KEYLENGTH= 16 bytes
     */
    byte key[ CryptoPP::AES::DEFAULT_KEYLENGTH ], iv[ CryptoPP::AES::BLOCKSIZE ];
    memset( key, 0x00, CryptoPP::AES::DEFAULT_KEYLENGTH );
    memset( iv, 0x00, CryptoPP::AES::BLOCKSIZE );
    T cipherText;
    cout << "\n\nPlain Text size is (" << plainText.size() << " bytes)" << "\n\n";
    cout << plainText << "\n\n";
    /*
     * Create Cipher Text
     */
    CryptoPP::AES::Encryption aesEncryption(key, CryptoPP::AES::DEFAULT_KEYLENGTH);
    CryptoPP::CBC_Mode_ExternalCipher::Encryption cbcEncryption( aesEncryption, iv );
    CryptoPP::StreamTransformationFilter stfEncryptor(cbcEncryption, new CryptoPP::StringSink( cipherText ) );
    stfEncryptor.Put( reinterpret_cast<const unsigned char*>( plainText.c_str() ), plainText.length() + 1 );
    stfEncryptor.MessageEnd();
    cout << "\n\nCipher Text size is (" << cipherText.size() << " bytes)" << std::endl;
    for( int i = 0; i < cipherText.size(); i++ ) {
        cout << "0x" << std::hex << (0xFF & static_cast<byte>(cipherText[i])) << " ";
    }
    return cipherText;
}

这是我的解密方法

/*
 * Decrypt the given text
 */

template<typename T>
T decryptText(T encryptedText) {
    /* Key and IV setup
     * AES encryption uses a secret key of a variable length (128-bit, 196-bit or 256-   
     * bit). This key is secretly exchanged between two parties before communication   
     * begins. DEFAULT_KEYLENGTH= 16 bytes
     */
    byte key[ CryptoPP::AES::DEFAULT_KEYLENGTH ], iv[ CryptoPP::AES::BLOCKSIZE ];
    memset( key, 0x00, CryptoPP::AES::DEFAULT_KEYLENGTH );
    memset( iv, 0x00, CryptoPP::AES::BLOCKSIZE );
    CryptoPP::AES::Decryption aesDecryption(key, CryptoPP::AES::DEFAULT_KEYLENGTH);
    CryptoPP::CBC_Mode_ExternalCipher::Decryption cbcDecryption( aesDecryption, iv );
    T decryptedText;
    CryptoPP::StreamTransformationFilter stfDecryptor(cbcDecryption, new CryptoPP::StringSink( decryptedText ) );
    stfDecryptor.Put( reinterpret_cast<const unsigned char*>( encryptedText.c_str() ), encryptedText.size() );
    stfDecryptor.MessageEnd();
    std::cout << "\n\nDecrypted Text is " << "\n\n";
    std::cout << "\n\n" << decryptedText << "\n\n";
    return decryptedText;
}

encryptText函数正常执行，我将其输出保存在mysql数据库中。调用decryptText函数时发生错误

An uncaught exception occurred: StreamTransformationFilter: ciphertext length is not a multiple of block size

我明白这个错误是因为加密文本也可能包含一些null（0）值。如何解密实际文本。

修改：

正如我要求在评论部分显示我的SQL查询。

这是我的sql查询，用于获取mysql数据库中保存的加密数据。

template<typename T1, typename T2>
void getUserSms(T1 userId,vector<T1>& smsIds,vector<T2>& text){
    try{
        mysql::connection db_cs(config_cs_db());
        auto sms = db_cs.run(select(all_of(us)).from(us).where(us.usersUserId == userId));
        while(!sms.empty()){
            const auto& row = sms.front();
            auto smsId = row.id.value();
            smsIds.push_back(smsId);
            auto encryptedText = row.text.value();
            auto plainText = decryptText(encryptedText);
            text.push_back(plainText);
            sms.pop_front();
        }
        return;
    }
    catch (const sqlpp::exception& e) {
        std::cerr << "Could not get user sms due to some reason ...!!\n";
        std:cerr << e.what() << "\n";
        return;
    }
}

我正在使用sqlpp11进行SQL查询。表格描述是

CREATE TABLE `user_sms`(
`id` BIGINT(50) NOT NULL AUTO_INCREMENT,
`sender_number` VARCHAR(20),
`text` VARCHAR(2000),
`incoming_time` TIMESTAMP,
`created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
`users_user_id` BIGINT(30),
PRIMARY KEY(`id`),
FOREIGN KEY(`users_user_id`) REFERENCES `users`(`user_id`)
)ENGINE=InnoDB DEFAULT CHARSET=utf8;

Answer 1

更改数组key和＆＃39; iv from字节to unsigned char`的数据类型
将text数据库表mysql中的user_sms类型从VARCHAR更改为BLOB。

CREATE TABLE `user_sms`( // Changes below is the changes has been made. `text` BLOB, )ENGINE=InnoDB DEFAULT CHARSET=utf8;

感谢jww寻求帮助。

StreamTransformationFilter：密文长度不是块大小的倍数？

1 个答案: