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Tcl

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 Tcl Downloads

Tcl

load ./chilkat.dll

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

set crypt [new_CkCrypt2]

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

CkCrypt2_put_KeyLength $crypt 256
CkCrypt2_put_CryptAlgorithm $crypt "AES"
CkCrypt2_put_CipherMode $crypt "ecb"
CkCrypt2_put_PaddingScheme $crypt 0
CkCrypt2_SetEncodedKey $crypt $keyAsBase64 "base64"

CkCrypt2_put_EncodingMode $crypt "base64"

# Pass the base64 representation of the encrypted data.
# (The EncodingMode indicates you are passing base64.)
set EK_result [CkCrypt2_decryptStringENC $crypt $encryptedBytesAsBase64]

puts "$EK_result"

delete_CkCrypt2 $crypt