aspnetcore/src/Microsoft.AspNet.Authentica.../OAuthHandler.cs

316 lines
12 KiB
C#

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Security.Claims;
using System.Security.Cryptography;
using System.Threading.Tasks;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Http.Authentication;
using Microsoft.AspNet.Http.Extensions;
using Microsoft.AspNet.Http.Features.Authentication;
using Microsoft.AspNet.WebUtilities;
using Microsoft.Framework.Internal;
using Microsoft.Framework.Logging;
using Microsoft.Framework.Primitives;
using Newtonsoft.Json.Linq;
namespace Microsoft.AspNet.Authentication.OAuth
{
public class OAuthHandler<TOptions> : AuthenticationHandler<TOptions> where TOptions : OAuthOptions
{
private static readonly RandomNumberGenerator CryptoRandom = RandomNumberGenerator.Create();
public OAuthHandler(HttpClient backchannel)
{
Backchannel = backchannel;
}
protected HttpClient Backchannel { get; private set; }
public override async Task<bool> InvokeAsync()
{
if (Options.CallbackPath.HasValue && Options.CallbackPath == Request.Path)
{
return await InvokeReturnPathAsync();
}
return false;
}
public async Task<bool> InvokeReturnPathAsync()
{
var ticket = await HandleAuthenticateOnceAsync();
if (ticket == null)
{
Logger.LogWarning("Invalid return state, unable to redirect.");
Response.StatusCode = 500;
return true;
}
var context = new SigningInContext(Context, ticket)
{
SignInScheme = Options.SignInScheme,
RedirectUri = ticket.Properties.RedirectUri,
};
ticket.Properties.RedirectUri = null;
await Options.Events.SigningIn(context);
if (context.SignInScheme != null && context.Principal != null)
{
await Context.Authentication.SignInAsync(context.SignInScheme, context.Principal, context.Properties);
}
if (!context.IsRequestCompleted && context.RedirectUri != null)
{
if (context.Principal == null)
{
// add a redirect hint that sign-in failed in some way
context.RedirectUri = QueryHelpers.AddQueryString(context.RedirectUri, "error", "access_denied");
}
Response.Redirect(context.RedirectUri);
context.RequestCompleted();
}
return context.IsRequestCompleted;
}
protected override async Task<AuthenticationTicket> HandleAuthenticateAsync()
{
AuthenticationProperties properties = null;
try
{
var query = Request.Query;
// TODO: Is this a standard error returned by servers?
var value = query["error"];
if (!StringValues.IsNullOrEmpty(value))
{
Logger.LogVerbose("Remote server returned an error: " + Request.QueryString);
// TODO: Fail request rather than passing through?
return null;
}
var code = query["code"];
var state = query["state"];
properties = Options.StateDataFormat.Unprotect(state);
if (properties == null)
{
return null;
}
// OAuth2 10.12 CSRF
if (!ValidateCorrelationId(properties))
{
return new AuthenticationTicket(properties, Options.AuthenticationScheme);
}
if (StringValues.IsNullOrEmpty(code))
{
// Null if the remote server returns an error.
return new AuthenticationTicket(properties, Options.AuthenticationScheme);
}
var tokens = await ExchangeCodeAsync(code, BuildRedirectUri(Options.CallbackPath));
if (string.IsNullOrEmpty(tokens.AccessToken))
{
Logger.LogWarning("Access token was not found");
return new AuthenticationTicket(properties, Options.AuthenticationScheme);
}
var identity = new ClaimsIdentity(Options.ClaimsIssuer);
if (Options.SaveTokensAsClaims)
{
identity.AddClaim(new Claim("access_token", tokens.AccessToken,
ClaimValueTypes.String, Options.ClaimsIssuer));
if (!string.IsNullOrEmpty(tokens.RefreshToken))
{
identity.AddClaim(new Claim("refresh_token", tokens.RefreshToken,
ClaimValueTypes.String, Options.ClaimsIssuer));
}
if (!string.IsNullOrEmpty(tokens.TokenType))
{
identity.AddClaim(new Claim("token_type", tokens.TokenType,
ClaimValueTypes.String, Options.ClaimsIssuer));
}
if (!string.IsNullOrEmpty(tokens.ExpiresIn))
{
identity.AddClaim(new Claim("expires_in", tokens.ExpiresIn,
ClaimValueTypes.String, Options.ClaimsIssuer));
}
}
return await CreateTicketAsync(identity, properties, tokens);
}
catch (Exception ex)
{
Logger.LogError("Authentication failed", ex);
return new AuthenticationTicket(properties, Options.AuthenticationScheme);
}
}
protected virtual async Task<OAuthTokenResponse> ExchangeCodeAsync(string code, string redirectUri)
{
var tokenRequestParameters = new Dictionary<string, string>()
{
{ "client_id", Options.ClientId },
{ "redirect_uri", redirectUri },
{ "client_secret", Options.ClientSecret },
{ "code", code },
{ "grant_type", "authorization_code" },
};
var requestContent = new FormUrlEncodedContent(tokenRequestParameters);
var requestMessage = new HttpRequestMessage(HttpMethod.Post, Options.TokenEndpoint);
requestMessage.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
requestMessage.Content = requestContent;
var response = await Backchannel.SendAsync(requestMessage, Context.RequestAborted);
response.EnsureSuccessStatusCode();
var payload = JObject.Parse(await response.Content.ReadAsStringAsync());
return new OAuthTokenResponse(payload);
}
protected virtual async Task<AuthenticationTicket> CreateTicketAsync(ClaimsIdentity identity, AuthenticationProperties properties, OAuthTokenResponse tokens)
{
var context = new OAuthCreatingTicketContext(Context, Options, Backchannel, tokens)
{
Principal = new ClaimsPrincipal(identity),
Properties = properties
};
await Options.Events.CreatingTicket(context);
if (context.Principal?.Identity == null)
{
return null;
}
return new AuthenticationTicket(context.Principal, context.Properties, Options.AuthenticationScheme);
}
protected override async Task<bool> HandleUnauthorizedAsync([NotNull] ChallengeContext context)
{
var properties = new AuthenticationProperties(context.Properties);
if (string.IsNullOrEmpty(properties.RedirectUri))
{
properties.RedirectUri = CurrentUri;
}
// OAuth2 10.12 CSRF
GenerateCorrelationId(properties);
var authorizationEndpoint = BuildChallengeUrl(properties, BuildRedirectUri(Options.CallbackPath));
var redirectContext = new OAuthRedirectToAuthorizationContext(
Context, Options,
properties, authorizationEndpoint);
await Options.Events.RedirectToAuthorizationEndpoint(redirectContext);
return true;
}
protected override Task HandleSignOutAsync(SignOutContext context)
{
throw new NotSupportedException();
}
protected override Task HandleSignInAsync(SignInContext context)
{
throw new NotSupportedException();
}
protected override Task<bool> HandleForbiddenAsync(ChallengeContext context)
{
throw new NotSupportedException();
}
protected virtual string BuildChallengeUrl(AuthenticationProperties properties, string redirectUri)
{
var scope = FormatScope();
var state = Options.StateDataFormat.Protect(properties);
var queryBuilder = new QueryBuilder()
{
{ "client_id", Options.ClientId },
{ "scope", scope },
{ "response_type", "code" },
{ "redirect_uri", redirectUri },
{ "state", state },
};
return Options.AuthorizationEndpoint + queryBuilder.ToString();
}
protected virtual string FormatScope()
{
// OAuth2 3.3 space separated
return string.Join(" ", Options.Scope);
}
protected void GenerateCorrelationId([NotNull] AuthenticationProperties properties)
{
var correlationKey = Constants.CorrelationPrefix + Options.AuthenticationScheme;
var nonceBytes = new byte[32];
CryptoRandom.GetBytes(nonceBytes);
var correlationId = Base64UrlTextEncoder.Encode(nonceBytes);
var cookieOptions = new CookieOptions
{
HttpOnly = true,
Secure = Request.IsHttps
};
properties.Items[correlationKey] = correlationId;
Response.Cookies.Append(correlationKey, correlationId, cookieOptions);
}
protected bool ValidateCorrelationId([NotNull] AuthenticationProperties properties)
{
var correlationKey = Constants.CorrelationPrefix + Options.AuthenticationScheme;
var correlationCookie = Request.Cookies[correlationKey];
if (string.IsNullOrEmpty(correlationCookie))
{
Logger.LogWarning("{0} cookie not found.", correlationKey);
return false;
}
var cookieOptions = new CookieOptions
{
HttpOnly = true,
Secure = Request.IsHttps
};
Response.Cookies.Delete(correlationKey, cookieOptions);
string correlationExtra;
if (!properties.Items.TryGetValue(
correlationKey,
out correlationExtra))
{
Logger.LogWarning("{0} state property not found.", correlationKey);
return false;
}
properties.Items.Remove(correlationKey);
if (!string.Equals(correlationCookie, correlationExtra, StringComparison.Ordinal))
{
Logger.LogWarning("{0} correlation cookie and state property mismatch.", correlationKey);
return false;
}
return true;
}
}
}