Hello,

would you please provide me with some simple sample of how to use the
DESCryptoServiceProvider to encrypt a buffer

byte[] buffer;

with key

byte[] key;

I saw some sample using Streams, but is there a simpler method working for
buffers?

O.

Hello Ondrej Sevecek" ondra_at_sevecek_dt_com,

you have to use CryptoStream. You could couple it with a MemoryStream to
do it all in-Memory buffer based.

if have an example here
http://www.leastprivilege.com/PermaLink.aspx?guid=f73ca1e0-bcfa-4563-862f-eb06ab317075

which uses RijndaelManaged and a FileStream. Should be easy to modify

Dominick Baier - DevelopMentor
www.leastprivilege.com

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Working with buffers... something like following shall do it (not sure if it
simplier :-):

    SymmetricAlgorithm algorithm = DES.Create();
    ICryptoTransform encryptor = algorithm.CreateEncryptor();
    int blockByteSize = algorithm.BlockSize / 8;
    int nBlocks = ((data.Length+blockByteSize-1)/blockByteSize);
    Byte[] encryptedData = new Byte[nBlocks*blockByteSize];
    for (int i = 0; i < nBlocks; i++)
    {
     if (i == nBlocks - 1)
     {
      Byte[] lastBlock = encryptor.TransformFinalBlock(data, i *
blockByteSize, nBlocks * blockByteSize - data.Length);
      Array.Copy(lastBlock, 0, encryptedData, i * blockByteSize,
lastBlock.Length);
     }
     else
     {
      encryptor.TransformBlock(
       data, i * blockByteSize, blockByteSize,
       encryptedData, i * blockByteSize);
     }
    }

-Valery
http://www.harper.no/valery

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