UA-.NETStandard/SampleApplications/Workshop/Reference/ConsoleReferenceServer/ReferenceServer.cs

/* ========================================================================
 * Copyright (c) 2005-2016 The OPC Foundation, Inc. All rights reserved.
 *
 * OPC Foundation MIT License 1.00
 * 
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
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 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
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 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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 * OTHER DEALINGS IN THE SOFTWARE.
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 * ======================================================================*/

using System;
using System.Collections.Generic;
using Opc.Ua;
using Opc.Ua.Server;
using System.Reflection;

namespace Quickstarts.ReferenceServer
{
    /// <summary>
    /// Implements a basic Quickstart Server.
    /// </summary>
    /// <remarks>
    /// Each server instance must have one instance of a StandardServer object which is
    /// responsible for reading the configuration file, creating the endpoints and dispatching
    /// incoming requests to the appropriate handler.
    /// 
    /// This sub-class specifies non-configurable metadata such as Product Name and initializes
    /// the EmptyNodeManager which provides access to the data exposed by the Server.
    /// </remarks>
    public partial class ReferenceServer : StandardServer
    {
        #region Overridden Methods
        /// <summary>
        /// Creates the node managers for the server.
        /// </summary>
        /// <remarks>
        /// This method allows the sub-class create any additional node managers which it uses. The SDK
        /// always creates a CoreNodeManager which handles the built-in nodes defined by the specification.
        /// Any additional NodeManagers are expected to handle application specific nodes.
        /// </remarks>
        protected override MasterNodeManager CreateMasterNodeManager(IServerInternal server, ApplicationConfiguration configuration)
        {
            Utils.Trace("Creating the Node Managers.");

            List<INodeManager> nodeManagers = new List<INodeManager>();

            // create the custom node managers.
            nodeManagers.Add(new EmptyNodeManager(server, configuration));
            
            // create master node manager.
            return new MasterNodeManager(server, configuration, null, nodeManagers.ToArray());
        }

        /// <summary>
        /// Loads the non-configurable properties for the application.
        /// </summary>
        /// <remarks>
        /// These properties are exposed by the server but cannot be changed by administrators.
        /// </remarks>
        protected override ServerProperties LoadServerProperties()
        {
            ServerProperties properties = new ServerProperties();

            properties.ManufacturerName = "OPC Foundation";
            properties.ProductName      = "Quickstart Reference Server";
            properties.ProductUri       = "http://opcfoundation.org/Quickstart/ReferenceServer/v1.0";
            properties.SoftwareVersion  = Utils.GetAssemblySoftwareVersion();
            properties.BuildNumber      = Utils.GetAssemblyBuildNumber();
            properties.BuildDate        = Utils.GetAssemblyTimestamp();

            // TBD - All applications have software certificates that need to added to the properties.

            return properties;
        }

        /// <summary>
        /// Creates the resource manager for the server.
        /// </summary>
        protected override ResourceManager CreateResourceManager(IServerInternal server, ApplicationConfiguration configuration)
        {
            ResourceManager resourceManager = new ResourceManager(server, configuration);

            System.Reflection.FieldInfo[] fields = typeof(StatusCodes).GetFields(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Static);

            foreach (System.Reflection.FieldInfo field in fields)
            {
                uint? id = field.GetValue(typeof(StatusCodes)) as uint?;

                if (id != null)
                {
                    resourceManager.Add(id.Value, "en-US", field.Name);
                }
            }

            return resourceManager;
        }

        /// <summary>
        /// Called after the server has been started.
        /// </summary>
        protected override void OnServerStarted(IServerInternal server)
        {
            base.OnServerStarted(server);

            // request notifications when the user identity is changed. all valid users are accepted by default.
            server.SessionManager.ImpersonateUser += new ImpersonateEventHandler(SessionManager_ImpersonateUser);
        }

        /// <summary>
        /// Called when a client tries to change its user identity.
        /// </summary>
        private void SessionManager_ImpersonateUser(Session session, ImpersonateEventArgs args)
        {
            // check for a user name token.
            UserNameIdentityToken userNameToken = args.NewIdentity as UserNameIdentityToken;

            if (userNameToken != null)
            {
                VerifyPassword(userNameToken.UserName, userNameToken.DecryptedPassword);
                args.Identity = new UserIdentity(userNameToken);
                return;
            }
        }

        /// <summary>
        /// Validates the password for a username token.
        /// </summary>
        private void VerifyPassword(string userName, string password)
        {
            if (String.IsNullOrEmpty(userName))
            {
                // an empty username is not accepted.
                throw ServiceResultException.Create(StatusCodes.BadIdentityTokenInvalid,
                    "Security token is not a valid username token. An empty username is not accepted.");
            }

            if (String.IsNullOrEmpty(password))
            {
                // an empty password is not accepted.
                throw ServiceResultException.Create(StatusCodes.BadIdentityTokenRejected,
                    "Security token is not a valid username token. An empty password is not accepted.");
            }

            if (!((userName == "user1" && password == "password") ||
                 (userName == "user2" && password == "password1")))
            {
                // construct translation object with default text.
                TranslationInfo info = new TranslationInfo(
                    "InvalidPassword",
                    "en-US",
                    "Invalid username or password.",
                    userName);

                // create an exception with a vendor defined sub-code.
                throw new ServiceResultException(new ServiceResult(
                    StatusCodes.BadUserAccessDenied,
                    "InvalidPassword",
                    "http://opcfoundation.org/UA/Sample/",
                    new LocalizedText(info)));
            }
        }
        #endregion
    }
}