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namespace OAuth2ProtectedWebApi.Code {
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using DotNetOpenAuth.Messaging.Bindings;
using DotNetOpenAuth.OAuth2;
using DotNetOpenAuth.OAuth2.ChannelElements;
using DotNetOpenAuth.OAuth2.Messages;
using OAuth2ProtectedWebApi.Code;
/// <summary>
/// Provides application-specific policy and persistence for OAuth 2.0 authorization servers.
/// </summary>
public class AuthorizationServerHost : IAuthorizationServerHost {
/// <summary>
/// Storage for the cryptographic keys used to protect authorization codes, refresh tokens and access tokens.
/// </summary>
/// <remarks>
/// A single, hard-coded symmetric key is hardly adequate. Applications that rely on decent security should
/// replace this implementation with one that actually stores and retrieves keys in some persistent store
/// (e.g. a database). DotNetOpenAuth will automatically take care of generating, rotating, and expiring keys
/// if you provide a real implementation of this interface.
/// TODO: Consider replacing use of <see cref="HardCodedKeyCryptoKeyStore"/> with a real persisted database table.
/// </remarks>
internal static readonly ICryptoKeyStore HardCodedCryptoKeyStore = new HardCodedKeyCryptoKeyStore("p7J1L24Qj4KGYUOrnfENF0XAhqn6rZc5dx4nxvI22Kg=");
/// <summary>
/// Gets the store for storing crypto keys used to symmetrically encrypt and sign authorization codes and refresh tokens.
/// </summary>
/// <remarks>
/// This store should be kept strictly confidential in the authorization server(s)
/// and NOT shared with the resource server. Anyone with these secrets can mint
/// tokens to essentially grant themselves access to anything they want.
/// </remarks>
public ICryptoKeyStore CryptoKeyStore {
get { return HardCodedCryptoKeyStore; }
}
/// <summary>
/// Gets the authorization code nonce store to use to ensure that authorization codes can only be used once.
/// </summary>
/// <value>
/// The authorization code nonce store.
/// </value>
public INonceStore NonceStore {
get {
// TODO: Consider implementing a nonce store to mitigate replay attacks on authorization codes.
return null;
}
}
/// <summary>
/// Acquires the access token and related parameters that go into the formulation of the token endpoint's response to a client.
/// </summary>
/// <param name="accessTokenRequestMessage">Details regarding the resources that the access token will grant access to, and the identity of the client
/// that will receive that access.
/// Based on this information the receiving resource server can be determined and the lifetime of the access
/// token can be set based on the sensitivity of the resources.</param>
/// <returns>
/// A non-null parameters instance that DotNetOpenAuth will dispose after it has been used.
/// </returns>
public AccessTokenResult CreateAccessToken(IAccessTokenRequest accessTokenRequestMessage) {
// If your resource server and authorization server are different web apps,
// consider using asymmetric keys instead of symmetric ones by setting different
// properties on the access token below.
var accessToken = new AuthorizationServerAccessToken {
Lifetime = TimeSpan.FromHours(1),
SymmetricKeyStore = this.CryptoKeyStore,
};
var result = new AccessTokenResult(accessToken);
return result;
}
/// <summary>
/// Gets the client with a given identifier.
/// </summary>
/// <param name="clientIdentifier">The client identifier.</param>
/// <returns>
/// The client registration. Never null.
/// </returns>
/// <exception cref="ArgumentException">Thrown when no client with the given identifier is registered with this authorization server.</exception>
public IClientDescription GetClient(string clientIdentifier) {
// TODO: Consider adding a clients table in your database to track actual client accounts
// with authenticating secrets.
// For now, just allow all clients regardless of ID, and consider them "Public" clients.
return new AnyCallbackClient();
}
/// <summary>
/// Determines whether a described authorization is (still) valid.
/// </summary>
/// <param name="authorization">The authorization.</param>
/// <returns>
/// <c>true</c> if the original authorization is still valid; otherwise, <c>false</c>.
/// </returns>
/// <remarks>
/// <para>When establishing that an authorization is still valid,
/// it's very important to only match on recorded authorizations that
/// meet these criteria:</para>
/// 1) The client identifier matches.
/// 2) The user account matches.
/// 3) The scope on the recorded authorization must include all scopes in the given authorization.
/// 4) The date the recorded authorization was issued must be <em>no later</em> that the date the given authorization was issued.
/// <para>One possible scenario is where the user authorized a client, later revoked authorization,
/// and even later reinstated authorization. This subsequent recorded authorization
/// would not satisfy requirement #4 in the above list. This is important because the revocation
/// the user went through should invalidate all previously issued tokens as a matter of
/// security in the event the user was revoking access in order to sever authorization on a stolen
/// account or piece of hardware in which the tokens were stored. </para>
/// </remarks>
public bool IsAuthorizationValid(IAuthorizationDescription authorization) {
// If your application supports access revocation (highly recommended),
// this method should return false if the specified authorization is not
// discovered in your current authorizations table.
//// TODO: code here
return true;
}
/// <summary>
/// Determines whether a given set of resource owner credentials is valid based on the authorization server's user database
/// and if so records an authorization entry such that subsequent calls to <see cref="IsAuthorizationValid" /> would
/// return <c>true</c>.
/// </summary>
/// <param name="userName">Username on the account.</param>
/// <param name="password">The user's password.</param>
/// <param name="accessRequest">The access request the credentials came with.
/// This may be useful if the authorization server wishes to apply some policy based on the client that is making the request.</param>
/// <returns>
/// A value that describes the result of the authorization check.
/// </returns>
/// <exception cref="System.NotSupportedException"></exception>
public AutomatedUserAuthorizationCheckResponse CheckAuthorizeResourceOwnerCredentialGrant(string userName, string password, IAccessTokenRequest accessRequest) {
// TODO: Consider only accepting resource owner credential grants from specific clients
// based on accessRequest.ClientIdentifier and accessRequest.ClientAuthenticated.
if (Membership.ValidateUser(userName, password)) {
// Add an entry to your authorization table to record that access was granted so that
// you can conditionally return true from IsAuthorizationValid when the row is discovered.
//// TODO: code here
// Inform DotNetOpenAuth that it may proceed to issue an access token.
return new AutomatedUserAuthorizationCheckResponse(accessRequest, true, Membership.GetUser(userName).UserName);
} else {
return new AutomatedUserAuthorizationCheckResponse(accessRequest, false, null);
}
}
/// <summary>
/// Determines whether an access token request given a client credential grant should be authorized
/// and if so records an authorization entry such that subsequent calls to <see cref="IsAuthorizationValid" /> would
/// return <c>true</c>.
/// </summary>
/// <param name="accessRequest">The access request the credentials came with.
/// This may be useful if the authorization server wishes to apply some policy based on the client that is making the request.</param>
/// <returns>
/// A value that describes the result of the authorization check.
/// </returns>
/// <exception cref="System.NotSupportedException"></exception>
public AutomatedAuthorizationCheckResponse CheckAuthorizeClientCredentialsGrant(IAccessTokenRequest accessRequest) {
// TODO: Consider implementing this if your application should support clients that access data that
// doesn't belong to specific people, or clients that have elevated privileges and can access other
// people's data.
if (accessRequest.ClientAuthenticated) {
// Before returning a positive response, be *very careful* to validate the requested access scope
// to make sure it is appropriate for the requesting client.
throw new NotSupportedException();
} else {
// Only authenticated clients should be given access.
return new AutomatedAuthorizationCheckResponse(accessRequest, false);
}
}
private class AnyCallbackClient : ClientDescription {
public override bool IsCallbackAllowed(Uri callback) {
return true;
}
}
}
}
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