public async Task ProcessAsync(IConnection connection, SmtpCommand command)
{
if (connection.CurrentMessage != null)
{
await connection.WriteResponseAsync(new SmtpResponse(StandardSmtpResponseCode.BadSequenceOfCommands,
"You already told me who the message was from"));
return;
}
if (command.ArgumentsText.Length == 0)
{
await connection.WriteResponseAsync(
new SmtpResponse(StandardSmtpResponseCode.SyntaxErrorInCommandArguments,
"Must specify from address or <>"));
return;
}
ArgumentsParser argumentsParser = new ArgumentsParser(command.ArgumentsText);
string[] arguments = argumentsParser.Arguments;
string from = arguments.First();
if (from.StartsWith("<"))
{
from = from.Remove(0, 1);
}
if (from.EndsWith(">"))
{
from = from.Remove(from.Length - 1, 1);
}
connection.Server.Behaviour.OnMessageStart(connection, from);
connection.NewMessage();
connection.CurrentMessage.ReceivedDate = _currentDateTimeProvider.GetCurrentDateTime();
connection.CurrentMessage.From = from;
try
{
await ParameterProcessorMap.ProcessAsync(connection, arguments.Skip(1).ToArray(), true);
await connection.WriteResponseAsync(new SmtpResponse(StandardSmtpResponseCode.OK, "New message started"));
}
catch
{
connection.AbortMessage();
throw;
}
}
public AuthMechanismProcessorStatus ProcessResponse(string data)
{
if (_challenge == null)
{
StringBuilder challenge = new StringBuilder();
challenge.Append(_random.GenerateRandomInteger(0, Int16.MaxValue));
challenge.Append(".");
challenge.Append(_dateTimeProvider.GetCurrentDateTime().Ticks.ToString());
challenge.Append("@");
challenge.Append(Connection.Server.Behaviour.DomainName);
_challenge = challenge.ToString();
string base64Challenge = Convert.ToBase64String(Encoding.ASCII.GetBytes(challenge.ToString()));
Connection.WriteResponse(new SmtpResponse(StandardSmtpResponseCode.AuthenticationContinue,
base64Challenge));
return(AuthMechanismProcessorStatus.Continue);
}
else
{
string response = ServerUtility.DecodeBase64(data);
string[] responseparts = response.Split(' ');
if (responseparts.Length != 2)
{
throw new SmtpServerException(new SmtpResponse(StandardSmtpResponseCode.AuthenticationFailure,
"Response in incorrect format - should be USERNAME RESPONSE"));
}
string username = responseparts[0];
string hash = responseparts[1];
Credentials = new CramMd5AuthenticationCredentials(username, _challenge, hash);
AuthenticationResult result =
Connection.Server.Behaviour.ValidateAuthenticationCredentials(Connection, Credentials);
switch (result)
{
case AuthenticationResult.Success:
return(AuthMechanismProcessorStatus.Success);
break;
default:
return(AuthMechanismProcessorStatus.Failed);
break;
}
}
}