我正在尝试让这段代码工作。来自Cryptopp AES
Demonstrates encryption and decryption using AES in CTR
唯一的区别是,我创建了函数 encryptAES 和 decryptAES 并插入了代码。 它无需创建这些功能即可工作。但现在我收到以下错误:AES/CTR 4 不是有效的 key 长度,但 key 长度为 16 位。
string encryptAES(const byte key[], const string& plain, const byte iv[])
{
try
{
string cipher;
CTR_Mode< AES >::Encryption e;
e.SetKeyWithIV(key, sizeof(key), iv);
// The StreamTransformationFilter adds padding
// as required. ECB and CBC Mode must be padded
// to the block size of the cipher.
StringSource(plain, true,
new StreamTransformationFilter(e,
new StringSink(cipher)
) // StreamTransformationFilter
); // StringSource
return cipher;
}
catch(const CryptoPP::Exception& e)
{
cerr << e.what() << endl;
return "";
}
}
string decryptAES(const byte key[], const string& cipher, const byte iv[])
{
try
{
string recovered;
CTR_Mode< AES >::Decryption d;
d.SetKeyWithIV(key, sizeof(key), iv);
// The StreamTransformationFilter removes
// padding as required.
StringSource s(cipher, true,
new StreamTransformationFilter(d,
new StringSink(recovered)
) // StreamTransformationFilter
); // StringSource
return recovered;
}
catch(const CryptoPP::Exception& e)
{
cerr << e.what() << endl;
return "";
}
}
int main(int argc, char *argv[])
{
AutoSeededRandomPool prng;
byte key[AES::DEFAULT_KEYLENGTH];
prng.GenerateBlock(key, sizeof(key));
byte iv[AES::BLOCKSIZE];
prng.GenerateBlock(iv, sizeof(iv));
string plain = "CTR Mode Test";
string encoded, cipher, recovered;
/*********************************\
\*********************************/
// Pretty print key
encoded.clear();
StringSource(key, sizeof(key), true,
new HexEncoder(
new StringSink(encoded)
) // HexEncoder
); // StringSource
cout << "key: " << encoded << endl;
// Pretty print iv
encoded.clear();
StringSource(iv, sizeof(iv), true,
new HexEncoder(
new StringSink(encoded)
) // HexEncoder
); // StringSource
cout << "iv: " << encoded << endl;
/*********************************\
\*********************************/
cout << "plain text: " << plain << endl;
cipher = encryptAES(key, plain, iv);
/*********************************\
\*********************************/
// Pretty print
encoded.clear();
StringSource(cipher, true,
new HexEncoder(
new StringSink(encoded)
) // HexEncoder
); // StringSource
cout << "cipher text: " << encoded << endl;
/*********************************\
\*********************************/
recovered = decryptAES(key, cipher, iv);
cout << "recovered text: " << recovered << endl;
cin.sync();
cin.get();
}
最佳答案
您的函数正在使用 const byte key[]
参数,它本质上被视为一个指针。因此 sizeof(key) 是您平台上指针的大小。
string encryptAES(const byte key[], const string& plain, const byte iv[])
// sizeof(key) is the size of a pointer
e.SetKeyWithIV(key, sizeof(key), iv);
您可以使用 std::vector<>
作为选项,或传递 key_len,例如:
string encryptAES(const byte key[], size_t key_len, const string& plain, const byte iv[])
// using key_len for the length of the key
e.SetKeyWithIV(key, key_len, iv);
我希望这是有道理的,因为同样的错误出现在几个地方。
关于c++ - AES 和 key 长度错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/13335688/