Base64 encode一个XXTEA加密字符串错误

Question

我想保护我的数据，所以我尝试用 XXTEA 加密它。我这样做：

输入字符串 -> XXTEA 加密 -> 输出字符串
outputString -> XXTEA 解密 -> inputString

加密解密一切正常。但是当我尝试在 XXTEA 加密后对输出进行 base64 编码并在 XXTEA 解密之前对其进行 base64 解码时，结果是错误的：

输入 -> XXTEA 加密 -> base64 编码 -> 输出
输出 -> base64 解码 -> XXTEA 解密 != 输入

当我用 http://www.tools4noobs.com/online_tools/xxtea_encrypt/ and http://www.tools4noobs.com/online_tools/xxtea_decrypt/

测试时

我的例子的输入字符串是hello，它的最终结果是bjz/S2f3Xkxr08hu

但是当我用我的代码测试时（见下文），最终结果是 bjz/Sw==

这是我的 encryption code:

std::string ProjectUtils::encrypt_data_xxtea(std::string input, std::string secret) {
//Encrypt with XXTEA
xxtea_long retLength = 0;

unsigned char data[input.length()];
strncpy((char*)data, input.c_str(), sizeof(data));
xxtea_long dataLength = (xxtea_long) sizeof(data);

unsigned char key[secret.length()];
strncpy((char*)key, secret.c_str(), sizeof(key));
xxtea_long keyLength = (xxtea_long) sizeof(key);

unsigned char *encryptedData = xxtea_encrypt(data, dataLength, key, keyLength, &retLength);

//Encode base64
char* out = NULL;
base64Encode(encryptedData, sizeof(encryptedData), &out);

CCLOG("xxtea encrypted data: %s", out);
return out;

}

这是我的 decryption code:

char* ProjectUtils::decrypt_data_xxtea(std::string input, std::string secret) {
//Decode base64
unsigned char* output = NULL;
base64Decode((unsigned char*)input.c_str(), (unsigned int)strlen(input.c_str()), &output);
xxtea_long dataLength = (xxtea_long) sizeof(output);

xxtea_long retLength = 0;

unsigned char key[secret.length()];
strncpy((char*)key, secret.c_str(), sizeof(key));
xxtea_long keyLength = (xxtea_long) sizeof(key);

//Decrypt with XXTEA
char *decryptedData = reinterpret_cast<char*>(xxtea_decrypt(output, dataLength, key, keyLength, &retLength));

CCLOG("xxtea decrypted data: %s", decryptedData);
return decryptedData;

}

你知道我的代码有什么问题吗？任何帮助，将不胜感激！非常感谢。

Answer 1

感谢您的代码，它对我有用）

我已经用实际的 retLength 替换了 base64 字符串的长度

base64Encode(encryptedData, retLength, &out);

返回，也获取实际尺寸

int outLength = cocos2d::base64Decode((unsigned char*)revertStr.c_str(), (unsigned int)strlen(revertStr.c_str()), &output);
char *decryptedData = reinterpret_cast<char*>(xxtea_decrypt(output, outLength, key, keyLength, &retLength));

Answer 2

这里是 cocos2d-x 3.4

的完整工作代码

std::string UserProfile::encryptString(std::string input, std::string secret) {
    //Encrypt with XXTEA
    xxtea_long retLength = 0;

    unsigned char data[input.length()];
    strncpy((char*)data, input.c_str(), sizeof(data));
    xxtea_long dataLength = (xxtea_long) sizeof(data);

    unsigned char key[secret.length()];
    strncpy((char*)key, secret.c_str(), sizeof(key));
    xxtea_long keyLength = (xxtea_long) sizeof(key);

    unsigned const char *encryptedData = reinterpret_cast<unsigned const char*>(xxtea_encrypt(data, dataLength, key, keyLength, &retLength));

    char* out = NULL;
    cocos2d::base64Encode(encryptedData, retLength, &out); // use real length returned by xxtea_encrypt
    CCLOG("xxtea encrypted data: [%s][%s]", encryptedData, out);


    std::string outStr(out); // make string object
    CCLOG("xxtea encrypted data: [%s][%s]", encryptedData, outStr.c_str());


    setStr(KEY, outStr); // function that store value in user defaults


    std::string revertStr = getStr(KEY); // get string value back
    CCLOG("xxtea revertStr: [%s]", revertStr.c_str());

    unsigned char* output = NULL;
    int outLength = cocos2d::base64Decode((unsigned char*)revertStr.c_str(), (unsigned int)strlen(revertStr.c_str()), &output); // get real length of decoded string
    char *decryptedData = reinterpret_cast<char*>(xxtea_decrypt(output, outLength, key, keyLength, &retLength)); // use it

    CCLOG("xxtea decrypted data: %s", decryptedData); // string the same as original for me

    return "";
}

Base64 encode一个XXTEA加密字符串错误

Base64 encode a XXTEA encrypted string error

c++

base64

cocos2d-x

xxtea