/// <summary>
/// Authenticates the ImapConnection using the username and password specified.
/// </summary>
/// <param name="username">A string value representing the username to authenticate.</param>
/// <param name="password">A string value representing the password to use for authentication.</param>
/// <exception cref="ImapAuthenticationException" />
/// <exception cref="ImapAuthenticationNotSupportedException" />
public void Login(string username, string password)
{
string command;
string result;
if (!(Connection.ConnectionState == ConnectionState.Connected))
{
throw new ImapConnectionException("Connection must be connected before authentication");
}
Connection.ConnectionState = ConnectionState.Authenticating;
//Moved from ImapConnect.Open because not all login methods will be advertised at the
//opening of the connection (Plain authentication usually won't be available until after
//a STARTTLS command has been sent for example. --Scott
//Not all servers advertise their capabilities on the OK response
//So ask for them seperatley.
string read;
string serverResponse;
_connection.Write("CAPABILITY\r\n");
read = _connection.Read();
//Check the Capabilities for available types
_connection.LoginType = ParseLoginType(read);
_connection.Read(); //Grab the extra OK line at the end
switch (Connection.LoginType)
{
case LoginType.PLAIN:
command = "LOGIN " + username + " " + password + "\r\n";
Connection.Write(command);
break;
case LoginType.LOGIN:
Connection.Write("AUTHENTICATE LOGIN\r\n");
serverResponse = Connection.Read();
Connection.UntaggedWrite(string.Format("{0}\r\n", base64Encode(username)));
serverResponse = Connection.Read();
Connection.UntaggedWrite(string.Format("{0}\r\n", base64Encode(password)));
break;
case LoginType.CRAM_MD5:
//Let the server know to use CRAM-MD5 and read it's response (Base64 encoded)
Connection.Write("AUTHENTICATE CRAM-MD5\r\n");
serverResponse = Connection.Read();
string hmac = HmacMd5(username, password, serverResponse);
Connection.UntaggedWrite(hmac + "\r\n");
break;
default:
throw new ImapAuthenticationNotSupportedException("Authentication type unsupported:" + Connection.LoginType.ToString());
}
result = Connection.Read();
if (result.StartsWith("* OK") || result.Substring(7, 2) == "OK")
{
Connection.ConnectionState = ConnectionState.Open;
}
else
{
Connection.ConnectionState = ConnectionState.Broken;
throw new ImapAuthenticationException("Authentication failed: " + result);
}
}
