Analysis and Evaluation of the Windows Event Log - Bill Buchanan

Barrie Codona, BSc (Hons) Network Computing, 2007
// The following code is from ‘Public Key RSA Encryption
// in C# .NET’ by Mathew John Schlabaugh.
// Available from the http://www.codeproject.com
// Specify the size of the key to be used in bits.
int dwKeySize = 1024;
// Decalre a new instance of the RSACryptoServiceProvider.
RSACryptoServiceProvider RSAProvider = new
RSACryptoServiceProvider(dwKeySize);
// Read the Servers public key from XML.
RSAProvider.FromXmlString(justPublicKey);
// Convert keysize from bits to bytes.
int keySize = dwKeySize / 8;
// Convert message to bytes.
byte[] bytes = Encoding.UTF32.GetBytes(chkMessage);
// Define a size that will be used for calculating a block size.
int maxLength = keySize - 42;
int dataLength = bytes.Length;
int iterations = dataLength / maxLength;
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i
maxLength) maxLength : dataLength - maxLength * i];
// Copy the smaller message into memory.
Buffer.BlockCopy(bytes, maxLength * i, tempBytes, 0,
tempBytes.Length);
// Encrypt the smaller message/section.
byte[] encryptedBytes = RSAProvider.Encrypt(tempBytes, true);
}
// Add the encrypted secion to the StringBuilder.
stringBuilder.Append(Convert.ToBase64String(encryptedBytes));
5.2.6 Sending to Server
Figure 24: Encrypting Data
For the client to be able to send any data to the data archiving system it will have to
converted into packet and then placed onto the TCP stream. Figure 25 shows this.
// Send the encrypted message to the Server.
server.Send(Encoding.ASCII.GetBytes(encryptedMessage));
// Specify the packet size.
Byte[] data = new byte[10240];
// Receive the acknowledgement from the Server.
int recv = server.Receive(data);
// Convert the recieved message to a string.
String stringData = Encoding.ASCII.GetString(data, 0, recv);
Figure 25: Sending Data to a Server
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