//-----------------------------------------------------------------------------
// <copyright file="SmtpNtlmAuthenticationModule.cs" company="Microsoft">
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
//-----------------------------------------------------------------------------
 
namespace System.Net.Mail
{
    using System;
    using System.Collections;
    using System.IO;
    using System.Net;
    using System.Security.Permissions;
    using System.Security.Authentication.ExtendedProtection;
    // 
 
#if MAKE_MAILCLIENT_PUBLIC
    internal
#else
    internal
#endif
 class SmtpDigestAuthenticationModule : ISmtpAuthenticationModule
    {
        Hashtable sessions = new Hashtable();
 
        internal SmtpDigestAuthenticationModule()
        {
        }
 
        #region ISmtpAuthenticationModule Members
 
        // Security this method will access NetworkCredential properties that demand UnmanagedCode and Environment Permission
        [EnvironmentPermission(SecurityAction.Assert, Unrestricted = true)]
        [SecurityPermission(SecurityAction.Assert, Flags = SecurityPermissionFlag.UnmanagedCode)]
        public Authorization Authenticate(string challenge, NetworkCredential credential, object sessionCookie, string spn, ChannelBinding channelBindingToken)
        {
 
            lock (this.sessions)
            {
                NTAuthentication clientContext = this.sessions[sessionCookie] as NTAuthentication;
                if (clientContext == null)
                {
                    if (credential == null){
                        return null;
                    }
                    // 
 
 
                   
 
                    this.sessions[sessionCookie] = clientContext = new NTAuthentication(false, "WDigest", credential, spn, ContextFlags.Connection, channelBindingToken);
                }
 
                string resp = clientContext.GetOutgoingBlob(challenge);
 
                if (!clientContext.IsCompleted)
                {
                    return new Authorization(resp, false);
                }
                else
                {
                    this.sessions.Remove(sessionCookie);
                    return new Authorization(resp, true);
                }
            }
        }
 
        public string AuthenticationType
        {
            get
            {
                return "WDigest";
            }
        }
 
        public void CloseContext(object sessionCookie) {
            // This is a no-op since the context is not
            // kept open by this module beyond auth completion.
        }
 
        #endregion
    }
}