1 files changed, 102 insertions, 0 deletions
diff --git a/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs
new file mode 100644
index 0000000..a502962
--- /dev/null
+++ b/src/DotNetOpenAuth.OAuth2/OAuth2/ChannelElements/AccessToken.cs
@@ -0,0 +1,102 @@
+//-----------------------------------------------------------------------
+// <copyright file="AccessToken.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.OAuth2.ChannelElements {
+	using System;
+	using System.Collections.Generic;
+	using System.Diagnostics.Contracts;
+	using System.Security.Cryptography;
+	using DotNetOpenAuth.Messaging;
+	using DotNetOpenAuth.Messaging.Bindings;
+
+	/// <summary>
+	/// A short-lived token that accompanies HTTP requests to protected data to authorize the request.
+	/// </summary>
+	internal class AccessToken : AuthorizationDataBag {
+		/// <summary>
+		/// Initializes a new instance of the <see cref="AccessToken"/> class.
+		/// </summary>
+		public AccessToken() {
+		}
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="AccessToken"/> class.
+		/// </summary>
+		/// <param name="authorization">The authorization to be described by the access token.</param>
+		/// <param name="lifetime">The lifetime of the access token.</param>
+		internal AccessToken(IAuthorizationDescription authorization, TimeSpan? lifetime) {
+			Requires.NotNull(authorization, "authorization");
+
+			this.ClientIdentifier = authorization.ClientIdentifier;
+			this.UtcCreationDate = authorization.UtcIssued;
+			this.User = authorization.User;
+			this.Scope.ResetContents(authorization.Scope);
+			this.Lifetime = lifetime;
+		}
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="AccessToken"/> class.
+		/// </summary>
+		/// <param name="clientIdentifier">The client identifier.</param>
+		/// <param name="scopes">The scopes.</param>
+		/// <param name="username">The username of the account that authorized this token.</param>
+		/// <param name="lifetime">The lifetime for this access token.</param>
+		internal AccessToken(string clientIdentifier, IEnumerable<string> scopes, string username, TimeSpan? lifetime) {
+			Requires.NotNullOrEmpty(clientIdentifier, "clientIdentifier");
+
+			this.ClientIdentifier = clientIdentifier;
+			this.Scope.ResetContents(scopes);
+			this.User = username;
+			this.Lifetime = lifetime;
+			this.UtcCreationDate = DateTime.UtcNow;
+		}
+
+		/// <summary>
+		/// Gets or sets the lifetime of the access token.
+		/// </summary>
+		/// <value>The lifetime.</value>
+		[MessagePart(Encoder = typeof(TimespanSecondsEncoder))]
+		internal TimeSpan? Lifetime { get; set; }
+
+		/// <summary>
+		/// Creates a formatter capable of serializing/deserializing an access token.
+		/// </summary>
+		/// <param name="signingKey">The crypto service provider with the authorization server's private key used to asymmetrically sign the access token.</param>
+		/// <param name="encryptingKey">The crypto service provider with the resource server's public key used to encrypt the access token.</param>
+		/// <returns>An access token serializer.</returns>
+		internal static IDataBagFormatter<AccessToken> CreateFormatter(RSACryptoServiceProvider signingKey, RSACryptoServiceProvider encryptingKey) {
+			Contract.Requires(signingKey != null || !signingKey.PublicOnly);
+			Contract.Requires(encryptingKey != null);
+			Contract.Ensures(Contract.Result<IDataBagFormatter<AccessToken>>() != null);
+
+			return new UriStyleMessageFormatter<AccessToken>(signingKey, encryptingKey);
+		}
+
+		/// <summary>
+		/// Checks the message state for conformity to the protocol specification
+		/// and throws an exception if the message is invalid.
+		/// </summary>
+		/// <remarks>
+		/// 	<para>Some messages have required fields, or combinations of fields that must relate to each other
+		/// in specialized ways.  After deserializing a message, this method checks the state of the
+		/// message to see if it conforms to the protocol.</para>
+		/// 	<para>Note that this property should <i>not</i> check signatures or perform any state checks
+		/// outside this scope of this particular message.</para>
+		/// </remarks>
+		/// <exception cref="ProtocolException">Thrown if the message is invalid.</exception>
+		protected override void EnsureValidMessage() {
+			base.EnsureValidMessage();
+
+			// Has this token expired?
+			if (this.Lifetime.HasValue) {
+				DateTime expirationDate = this.UtcCreationDate + this.Lifetime.Value;
+				if (expirationDate < DateTime.UtcNow) {
+					throw new ExpiredMessageException(expirationDate, this.ContainingMessage);
+				}
+			}
+		}
+	}
+}