Notifications to allow modification of generated XML

- Closes Sustainsys#978
- Closes Sustainsys#1158

Sustainsys.Saml2/Configuration/Saml2Notifications.cs

@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using System.Security.Claims;
 using System.Xml;
+using System.Xml.Linq;
 
 namespace Sustainsys.Saml2.Configuration
 {
@@ -25,6 +26,10 @@ public Action<Saml2AuthenticationRequest, IdentityProvider, IDictionary<string,
             AuthenticationRequestCreated
         { get; set; } = (request, provider, dictionary) => { };
 
+        public Action<Saml2AuthenticationRequest, XDocument, Saml2BindingType>
+            AuthenticationRequestXmlCreated
+        { get; set; } = (request, xDocument, Saml2BindingType) => { };
+
         /// <summary>
         /// Notification called when the SignIn command has produced a
         /// <see cref="CommandResult"/>, but before anything has been applied
@@ -124,6 +129,25 @@ public Func<Saml2LogoutResponse, StoredRequestState, bool>
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA1726:UsePreferredTerms", MessageId = "Logout")]
         public Action<CommandResult> LogoutCommandResultCreated { get; set; } = cr => { };
 
+        /// <summary>
+        /// Notification called when a logout request is created to initiate single log
+        /// out with an identity provider.
+        /// </summary>
+        public Action<Saml2LogoutRequest, ClaimsPrincipal, IdentityProvider> LogoutRequestCreated { get; set; } = (lr, user, idp) => { };
+
+        /// <summary>
+        /// Notification called when a logout request has been transformed to an XML node tree.
+        /// </summary>
+        public Action<Saml2LogoutRequest, XDocument, Saml2BindingType> LogoutRequestXmlCreated { get; set; } = (lr, xd, bt) => { };
+
+        /// <summary>
+        /// Notification called when a logout request has been received and processed and a Logout Response has been created.
+        /// </summary>
+        public Action<Saml2LogoutResponse, Saml2LogoutRequest, ClaimsPrincipal, IdentityProvider> LogoutResponseCreated { get; set; } 
+            = (resp, req, u, idp) => { };
+
+        public Action<Saml2LogoutResponse, XDocument, Saml2BindingType> LogoutResponseXmlCreated { get; set; } = (lr, xd, bt) => { };
+
         /// <summary>
         /// Notification called when metadata has been created, but before
         /// signing. At this point the contents of the metadata can be

Sustainsys.Saml2/Federation.cs

@@ -118,7 +118,7 @@ private void Init(string metadataLocation,
             LoadMetadata();
         }
 
-        private object metadataLoadLock = new object();
+        private readonly object metadataLoadLock = new object();
 
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes", Justification ="We want a retry, regardless of exception type")]
         private void LoadMetadata()

Sustainsys.Saml2/IdentityProvider.cs

@@ -15,6 +15,7 @@
 using System.Security.Claims;
 using System.Diagnostics.CodeAnalysis;
 using Sustainsys.Saml2.Tokens;
+using System.Xml.Linq;
 
 namespace Sustainsys.Saml2
 {
@@ -334,16 +335,34 @@ public Saml2AuthenticationRequest CreateAuthenticateRequest(
         public string OutboundSigningAlgorithm { get; set; }
 
         /// <summary>
-        /// Bind a Saml2AuthenticateRequest using the active binding of the idp,
+        /// Bind a Saml2 message using the active binding of the idp,
         /// producing a CommandResult with the result of the binding.
         /// </summary>
-        /// <param name="request">The AuthnRequest to bind.</param>
+        /// <remarks>
+        /// This overload does not support the usage of Xml Created notifications.
+        /// </remarks>
+        /// <param name="request">The Saml2 message to bind.</param>
         /// <returns>CommandResult with the bound request.</returns>
         public CommandResult Bind(ISaml2Message request)
         {
             return Saml2Binding.Get(Binding).Bind(request);
         }
 
+        /// <summary>
+        /// Bind a Saml2 message using the active binding of hte idp,
+        /// producing a CommandResult with the result of the binding.
+        /// </summary>
+        /// <typeparam name="TMessage">Type of the message.</typeparam>
+        /// <param name="message">The Saml2 message to bind.</param>
+        /// <param name="xmlCreatedNotification">Notification to call with Xml structure</param>
+        /// <returns>CommandResult with the bound message.</returns>
+        public CommandResult Bind<TMessage>(
+            TMessage message, Action<TMessage, XDocument, Saml2BindingType> xmlCreatedNotification)
+            where TMessage: ISaml2Message
+        {
+            return Saml2Binding.Get(Binding).Bind(message, spOptions.Logger, xmlCreatedNotification);
+        }
+
         private readonly ConfiguredAndLoadedSigningKeysCollection signingKeys =
             new ConfiguredAndLoadedSigningKeysCollection();
 

Sustainsys.Saml2/Internal/XDocumentExtensions.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Xml.Linq;
+
+namespace Sustainsys.Saml2.Internal
+{
+    static class XDocumentExtensions
+    {
+        public static string ToStringWithXmlDeclaration(this XDocument xDocument)
+        {
+            if (xDocument.Declaration != null)
+            {
+                return xDocument.Declaration?.ToString() + "\r\n" + xDocument.ToString();
+            }
+
+            return xDocument.ToString();
+        }
+    }
+}

Sustainsys.Saml2/SAML2P/ISaml2Message.cs

@@ -4,6 +4,7 @@
 using System.Security.Cryptography.X509Certificates;
 using System.Text;
 using System.Threading.Tasks;
+using System.Xml.Linq;
 using Sustainsys.Saml2.Metadata;
 
 namespace Sustainsys.Saml2.Saml2P
@@ -28,6 +29,12 @@ public interface ISaml2Message
         /// <returns>string containing the Xml data.</returns>
         string ToXml();
 
+        /// <summary>
+        /// Transforms the message to an XElement object tree.
+        /// </summary>
+        /// <returns>XElement with Xml representation of the message</returns>
+        XElement ToXElement();
+
         /// <summary>
         /// The name of the message to use in a query string or form input
         /// field. Typically "SAMLRequest" or "SAMLResponse".

Sustainsys.Saml2/SAML2P/ISaml2MessageExtensions.cs

@@ -0,0 +1,29 @@
+using Sustainsys.Saml2.Internal;
+using Sustainsys.Saml2.WebSso;
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Xml.Linq;
+
+namespace Sustainsys.Saml2.Saml2P
+{
+    static class Saml2MessageExtensions
+    {
+        /// <summary>
+        /// Serializes the message into wellformed XML.
+        /// </summary>
+        /// <param name="message">Saml2 message to transform to XML</param>
+        /// <param name="xmlCreatedNotification">Notification allowing modification of XML tree before serialization.</param>
+        /// <returns>string containing the Xml data.</returns>
+        public static string ToXml<TMessage>(
+            this TMessage message, Action<XDocument> xmlCreatedNotification)
+            where TMessage : ISaml2Message
+        {
+            var xDocument = new XDocument(message.ToXElement());
+
+            xmlCreatedNotification(xDocument);
+
+            return xDocument.ToStringWithXmlDeclaration();
+        }
+    }
+}

Sustainsys.Saml2/SAML2P/Saml2ArtifactResolve.cs

@@ -43,5 +43,10 @@ public override string ToXml()
                 new XElement(Saml2Namespaces.Saml2P + "Artifact", Artifact))
                 .ToString();
         }
+
+        public override XElement ToXElement()
+        {
+            throw new NotImplementedException();
+        }
     }
 }

Sustainsys.Saml2/SAML2P/Saml2AuthenticationRequest.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Globalization;
+using System.IO;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
@@ -38,7 +39,7 @@ protected override string LocalName
         /// </summary>
         /// <returns>XElement</returns>
         [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Globalization", "CA1308:NormalizeStringsToUppercase", Justification = "Lowercase demanded by specification.")]
-        public XElement ToXElement()
+        public override XElement ToXElement()
         {
             var x = new XElement(Saml2Namespaces.Saml2P + LocalName);
 
@@ -115,7 +116,7 @@ private void AddScoping(XElement xElement)
         }
 
         /// <summary>
-        /// Serializes the message into wellformed Xml.
+        /// Serializes the message into wellformed Xml
         /// </summary>
         /// <returns>string containing the Xml data.</returns>
         public override string ToXml()

Sustainsys.Saml2/SAML2P/Saml2LogoutRequest.cs

@@ -94,6 +94,11 @@ protected override string LocalName
         /// </summary>
         /// <returns>string containing the Xml data.</returns>
         public override string ToXml()
+        {
+            return ToXElement().ToString();
+        }
+
+        public override XElement ToXElement()
         {
             var x = new XElement(Saml2Namespaces.Saml2P + LocalName);
 
@@ -103,7 +108,7 @@ public override string ToXml()
             x.Add(new XElement(Saml2Namespaces.Saml2P + "SessionIndex",
                 SessionIndex));
 
-            return x.ToString();
+            return x;
         }
     }
 }

Sustainsys.Saml2/SAML2P/Saml2LogoutResponse.cs

@@ -5,6 +5,7 @@
 using System.Text;
 using System.Threading.Tasks;
 using System.Xml;
+using System.Xml.Linq;
 
 namespace Sustainsys.Saml2.Saml2P
 {
@@ -33,6 +34,27 @@ public override string ToXml()
             return doc.DocumentElement.OuterXml;
         }
 
+        public override XElement ToXElement()
+        {
+            var xe = new XElement(Saml2Namespaces.Saml2P + "LogoutResponse",
+                new XAttribute("ID", Id.Value),
+                new XAttribute("Version", "2.0"),
+                new XAttribute("IssueInstant", IssueInstant.ToSaml2DateTimeString()),
+                new XElement(Saml2Namespaces.Saml2P + "Status",
+                    new XElement(Saml2Namespaces.Saml2P + "StatusCode",
+                    new XAttribute("Value", StatusCodeHelper.FromCode(Status)))));
+
+            if(Issuer != null)
+            {
+                xe.AddFirst(new XElement(Saml2Namespaces.Saml2 + "Issuer", Issuer.Id));
+            }
+
+            xe.AddAttributeIfNotNullOrEmpty("InResponseTo", InResponseTo?.Value);
+            xe.AddAttributeIfNotNullOrEmpty("Destination", DestinationUrl?.OriginalString);
+
+            return xe;
+       }
+
         /// <summary>
         /// Appends xml for the Saml2LogoutResponse to the given parent node.
         /// </summary>

Sustainsys.Saml2/SAML2P/Saml2RequestBase.cs

@@ -18,22 +18,10 @@ namespace Sustainsys.Saml2.Saml2P
     /// </summary>
     public abstract class Saml2RequestBase : ISaml2Message
     {
-        private Saml2Id id = new Saml2Id("id" + Guid.NewGuid().ToString("N"));
-
         /// <summary>
         /// The id of the request.
         /// </summary>
-        public Saml2Id Id
-        {
-            get
-            {
-                return id;
-            }
-            protected set
-            {
-                id = value;
-            }
-        }
+        public Saml2Id Id { get; protected set; } = new Saml2Id("id" + Guid.NewGuid().ToString("N"));
 
         /// <summary>
         /// Version of the SAML request. Always returns "2.0"
@@ -47,19 +35,10 @@ public string Version
             }
         }
 
-        private readonly string issueInstant =
-            DateTime.UtcNow.ToSaml2DateTimeString();
-
         /// <summary>
         /// The instant that the request was issued (well actually, created).
         /// </summary>
-        public string IssueInstant
-        {
-            get
-            {
-                return issueInstant;
-            }
-        }
+        public string IssueInstant { get; } = DateTime.UtcNow.ToSaml2DateTimeString();
 
         /// <summary>
         /// SAML message name for requests - hard coded to SAMLRequest.
@@ -92,6 +71,12 @@ public string MessageName
         /// </summary>
         protected abstract string LocalName { get; }
 
+        /// <summary>
+        /// Transforms the message to an XElement object tree.
+        /// </summary>
+        /// <returns>XElement with Xml representation of the message</returns>
+        public abstract XElement ToXElement();
+
         /// <summary>
         /// Creates XNodes for the fields of the Saml2RequestBase class. These
         /// nodes should be added when creating XML out of derived classes.