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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 <C_CkCrypt2.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    const char *keyAsBase64;
    const char *encryptedBytesAsBase64;
    const char *EK_result;

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

    crypt = CkCrypt2_Create();

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

    CkCrypt2_putKeyLength(crypt,256);
    CkCrypt2_putCryptAlgorithm(crypt,"AES");
    CkCrypt2_putCipherMode(crypt,"ecb");
    CkCrypt2_putPaddingScheme(crypt,0);
    CkCrypt2_SetEncodedKey(crypt,keyAsBase64,"base64");

    CkCrypt2_putEncodingMode(crypt,"base64");

    // Pass the base64 representation of the encrypted data.
    // (The EncodingMode indicates you are passing base64.)
    EK_result = CkCrypt2_decryptStringENC(crypt,encryptedBytesAsBase64);

    printf("%s\n",EK_result);


    CkCrypt2_Dispose(crypt);

    }