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C++

AES Encryption ECB Mode with PKCS7 Padding

See more Encryption Examples

Duplicates the following C# code:
public static byte[] DecryptBySymmetricKey(string encryptedText, byte[] key)
  {
     string keyAsBase64 = Convert.ToBase64String(key);

     byte[] dataToDecrypt = Convert.FromBase64String(encryptedText);
     var keyBytes = key;
     AesManaged tdes = new AesManaged();
     tdes.KeySize = 256;
     tdes.BlockSize = 128;
     tdes.Key = keyBytes;
     tdes.Mode = CipherMode.ECB;
     tdes.Padding = PaddingMode.PKCS7;
     ICryptoTransform decrypt__1 = tdes.CreateDecryptor();
     byte[] deCipher = decrypt__1.TransformFinalBlock(dataToDecrypt, 0, dataToDecrypt.Length);
     tdes.Clear();
     string EK_result = Convert.ToBase64String(deCipher);
     return EK_result;
}

Chilkat C++ Downloads

C++
#include <CkCrypt2.h>

void ChilkatSample(void)
    {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkCrypt2 crypt;

    // In the C# code above that is to be duplicated here, use the base64 encoded key.
    const char *keyAsBase64 = "...";
    const char *encryptedBytesAsBase64 = "....";

    crypt.put_KeyLength(256);
    crypt.put_CryptAlgorithm("AES");
    crypt.put_CipherMode("ecb");
    crypt.put_PaddingScheme(0);
    crypt.SetEncodedKey(keyAsBase64,"base64");

    crypt.put_EncodingMode("base64");

    // Pass the base64 representation of the encrypted data.
    // (The EncodingMode indicates you are passing base64.)
    const char *EK_result = crypt.decryptStringENC(encryptedBytesAsBase64);

    std::cout << EK_result << "\r\n";
    }