/// <summary>
/// Authenticates using the CRAM-MD5 authentication method
/// </summary>
/// <param name="username">The username</param>
/// <param name="password">The user password</param>
/// <exception cref="NotSupportedException">Thrown when the server does not support AUTH CRAM-MD5</exception>
/// <exception cref="InvalidLoginException">If the user credentials was not accepted</exception>
/// <exception cref="PopServerLockedException">If the server said the the mailbox was locked</exception>
/// <exception cref="LoginDelayException">If the server rejects the login because of too recent logins</exception>
private void AuthenticateUsingCramMd5(string username, string password)
{
// Example of communication:
// C: AUTH CRAM-MD5
// S: + PDE4OTYuNjk3MTcwOTUyQHBvc3RvZmZpY2UucmVzdG9uLm1jaS5uZXQ+
// C: dGltIGI5MTNhNjAyYzdlZGE3YTQ5NWI0ZTZlNzMzNGQzODkw
// S: +OK CRAM authentication successful
// Other example, where AUTH CRAM-MD5 is not supported
// C: AUTH CRAM-MD5
// S: -ERR Authentication method CRAM-MD5 not supported
try
{
SendCommand("AUTH CRAM-MD5");
}
catch (PopServerException e)
{
// A PopServerException will be thrown if the server responds with a -ERR not supported
throw new NotSupportedException("CRAM-MD5 authentication not supported", e);
}
// Fetch out the challenge from the server response
string challenge = LastServerResponse.Substring(2);
// Compute the challenge response
string response = CramMd5.ComputeDigest(username, password, challenge);
// Send the response to the server
SendCommand(response);
// Authentication was successful if no exceptions thrown before getting here
}
