1 files changed, 113 insertions, 0 deletions
diff --git a/src/DotNetOpenAuth.OAuth2.ClientAuthorization/OAuth2/IClientDescription.cs b/src/DotNetOpenAuth.OAuth2.ClientAuthorization/OAuth2/IClientDescription.cs
new file mode 100644
index 0000000..d30151b
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+++ b/src/DotNetOpenAuth.OAuth2.ClientAuthorization/OAuth2/IClientDescription.cs
@@ -0,0 +1,113 @@
+//-----------------------------------------------------------------------
+// <copyright file="IClientDescription.cs" company="Outercurve Foundation">
+//     Copyright (c) Outercurve Foundation. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.OAuth2 {
+	using System;
+	using System.Collections.Generic;
+	using System.Diagnostics.Contracts;
+
+	/// <summary>
+	/// A description of a client from an Authorization Server's point of view.
+	/// </summary>
+	[ContractClass(typeof(IClientDescriptionContract))]
+	public interface IClientDescription {
+		/// <summary>
+		/// Gets the client secret.
+		/// </summary>
+		string Secret { get; }
+
+		/// <summary>
+		/// Gets the callback to use when an individual authorization request
+		/// does not include an explicit callback URI.
+		/// </summary>
+		/// <value>An absolute URL; or <c>null</c> if none is registered.</value>
+		Uri DefaultCallback { get; }
+
+		/// <summary>
+		/// Gets the type of the client.
+		/// </summary>
+		ClientType ClientType { get; }
+
+		/// <summary>
+		/// Determines whether a callback URI included in a client's authorization request 
+		/// is among those allowed callbacks for the registered client.
+		/// </summary>
+		/// <param name="callback">The absolute URI the client has requested the authorization result be received at.</param>
+		/// <returns>
+		/// <c>true</c> if the callback URL is allowable for this client; otherwise, <c>false</c>.
+		/// </returns>
+		/// <remarks>
+		/// <para>
+		/// At the point this method is invoked, the identity of the client has <em>not</em>
+		/// been confirmed.  To avoid open redirector attacks, the alleged client's identity
+		/// is used to lookup a list of allowable callback URLs to make sure that the callback URL
+		/// the actual client is requesting is one of the expected ones.
+		/// </para>
+		/// <para>
+		/// From OAuth 2.0 section 2.1: 
+		/// The authorization server SHOULD require the client to pre-register
+		/// their redirection URI or at least certain components such as the
+		/// scheme, host, port and path.  If a redirection URI was registered,
+		/// the authorization server MUST compare any redirection URI received at
+		/// the authorization endpoint with the registered URI.
+		/// </para>
+		/// </remarks>
+		bool IsCallbackAllowed(Uri callback);
+	}
+
+	/// <summary>
+	/// Contract class for the <see cref="IClientDescription"/> interface.
+	/// </summary>
+	[ContractClassFor(typeof(IClientDescription))]
+	internal abstract class IClientDescriptionContract : IClientDescription {
+		#region IClientDescription Members
+
+		/// <summary>
+		/// Gets the client secret.
+		/// </summary>
+		/// <value></value>
+		string IClientDescription.Secret {
+			get { throw new NotImplementedException(); }
+		}
+
+		/// <summary>
+		/// Gets the type of the client.
+		/// </summary>
+		ClientType IClientDescription.ClientType {
+			get { throw new NotImplementedException(); }
+		}
+
+		/// <summary>
+		/// Gets the callback to use when an individual authorization request
+		/// does not include an explicit callback URI.
+		/// </summary>
+		/// <value>
+		/// An absolute URL; or <c>null</c> if none is registered.
+		/// </value>
+		Uri IClientDescription.DefaultCallback {
+			get {
+				Contract.Ensures(Contract.Result<Uri>() == null || Contract.Result<Uri>().IsAbsoluteUri);
+				throw new NotImplementedException();
+			}
+		}
+
+		/// <summary>
+		/// Determines whether a callback URI included in a client's authorization request
+		/// is among those allowed callbacks for the registered client.
+		/// </summary>
+		/// <param name="callback">The requested callback URI.</param>
+		/// <returns>
+		///   <c>true</c> if the callback is allowed; otherwise, <c>false</c>.
+		/// </returns>
+		bool IClientDescription.IsCallbackAllowed(Uri callback) {
+			Requires.NotNull(callback, "callback");
+			Requires.True(callback.IsAbsoluteUri, "callback");
+			throw new NotImplementedException();
+		}
+
+		#endregion
+	}
+}