private static PopCommandResult AuthenticateWithAppropriateMechanism(PopSession session,
bool allowInsecureMechanism,
ICredentialsByHost credentials,
string username,
IEnumerable<string> usingSaslMechanisms)
{
PopCommandResult result = null;
foreach (var mechanism in usingSaslMechanisms) {
if (!allowInsecureMechanism && SaslClientMechanism.IsMechanismPlainText(mechanism))
// disallow plain text mechanism
continue;
if (string.Equals(mechanism, SaslMechanisms.Anonymous, StringComparison.OrdinalIgnoreCase))
// disallow 'ANONYMOUS' mechanism
continue;
var authMechanism = PopAuthenticationMechanism.GetKnownOrCreate(mechanism);
if (session.ServerCapabilities.IsCapable(authMechanism)) {
result = session.Auth(credentials, username, authMechanism);
if (result.Succeeded)
break;
}
}
if ((result == null || result.Failed) && allowInsecureMechanism) {
if (session.ApopAvailable)
result = session.Apop(credentials, username);
}
if ((result == null || result.Failed) && allowInsecureMechanism)
result = session.Login(credentials, username);
return result;
}
private static PopCommandResult AuthenticateAsAnonymous(PopSession session,
string username,
bool canFallback)
{
PopCommandResult result = null;
if (string.IsNullOrEmpty(username))
username = "******";
if (session.ServerCapabilities.IsCapable(PopAuthenticationMechanism.Anonymous))
// try AUTH ANONYUMOUS
result = session.Auth(new NetworkCredential(username, string.Empty),
null,
PopAuthenticationMechanism.Anonymous);
if (result == null || (result.Failed && canFallback))
// try anonymous LOGIN
result = session.Login(new NetworkCredential("anonymous", username),
null);
return result;
}