Obtaining a valid access token for Microsoft Graph API - azure

I am working on an ASP.NET MVC5 Web App that uses Azure ADAL libraries to authenticate users, it works fine, however, when I manually send requests to graph, ex: GET https://graph.microsoft.com/v1.0/me or GET https://graph.microsoft.com/v1.0/groups?$filter=from/displayName eq 'whatever'.
I have tried updating the App Registration in Azure as to add the required Graph permissions, and I have also tried creating new app registrations, no matter what I do my requests will always respond 401 Unauthorized, is there anything I am missing?
EDIT: Example response from Postman
{
"error": {
"code": "InvalidAuthenticationToken",
"message": "Access token validation failure.",
"innerError": {
"request-id": "a142576b-acce-4e59-8a8d-adede61aaf59",
"date": "2017-04-05T13:27:36"
}
}
}
EDIT: C# Request Example
public async Task<GroupGraph> GetGroupIdByDisplayName(string displayName)
{
var accessToken = await authenticationService.GetTokenUserOnly();
GroupGraph groupGraphResponse = null;
using (var client = new HttpClient())
{
using (var request = new HttpRequestMessage(HttpMethod.Get, $"https://graph.microsoft.com/v1.0/groups?$filter=from/displayName eq '{displayName}'"))
{
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
using (var response = client.SendAsync(request).Result)
{
if (response.IsSuccessStatusCode)
{
using (var content = response.Content)
{
var result = await content.ReadAsStringAsync();
groupGraphResponse = JsonConvert.DeserializeObject<GroupGraph>(result);
}
}
}
}
}
return groupGraphResponse;
}
EDIT: The way I obtain the token
public async Task<string> GetTokenUserOnly()
{
string signedInUserID = ClaimsPrincipal.Current.FindFirst(ClaimTypes.NameIdentifier).Value;
string tenantID = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/tenantid").Value;
string userObjectID = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier").Value;
// get a token for the Graph without triggering any user interaction (from the cache, via multi-resource refresh token, etc)
ClientCredential clientcred = new ClientCredential(clientId, appKey);
// initialize AuthenticationContext with the token cache of the currently signed in user, as kept in the app's database
AuthenticationContext authenticationContext = new AuthenticationContext(aadInstance + tenantID, new TableTokenCache(signedInUserID));
//AuthenticationResult authenticationResult = await authenticationContext.AcquireTokenSilentAsync(graphResourceID, clientcred, new UserIdentifier(userObjectID, UserIdentifierType.UniqueId));
AuthenticationResult authenticationResult = authenticationContext.AcquireToken(graphResourceID, clientcred);
return authenticationResult.AccessToken;
}

You can't use ADAL to get tokens for graph.microsoft.com. ADAL is for graph.windows.net.
In order to get tokens for the Graph library (graph.windows.com) look into the Nuget Package Microsoft.Graph. Microsoft also has some documentation on how to pull user info using Graph.
Be forewarned though, using Graph Libraries and ADAL libraries side by side can lead to some weird side effects, such as the credential cache being cleared.

It seems you are using the client credential grant flow to acquire the access token for graph api(graphResourceID is https://graph.microsoft.com ?) :
AuthenticationResult authenticationResult = authenticationContext.AcquireToken(graphResourceID, clientcred);
So you need to grant app permission in azure ad portal :
For error "Access token validation failure" , you could use online tool like http://jwt.calebb.net/ to decode your access token , check the audience or lifetime of the access token .

To obtain a valid token for Microsoft Graph API you can use Azure.Identity.
To use any implementation of TokenCredential we need to build our own IAuthenticationProvider.
public class TokenCredentialAuthenticationProvider : IAuthenticationProvider
{
private readonly TokenCredential _tokenCredential;
public TokenCredentialAuthenticationProvider(TokenCredential tokenCredential)
{
_tokenCredential = tokenCredential;
}
public async Task AuthenticateRequestAsync(HttpRequestMessage request)
{
var accessToken = await _tokenCredential.GetTokenAsync(new TokenRequestContext(new[] { "https://graph.microsoft.com" }), CancellationToken.None);
request.Headers.Authorization = new AuthenticationHeaderValue("bearer", accessToken.Token);
}
}
Now we can for instance use AzureCliCredential to acquire an access token.
Open Powershell and type in az login in order to login with your Azure AD account.
In Azure you could also use Managed Identity to get a token based on a Azure resource e.g. Azure App Service. Here need to use ManagedIdentityToken.
Usage:
var client = new GraphServiceClient(new TokenCredentialAuthenticationProvider(new AzureCliCredential()));
var user = await client.Me.Request().GetAsync();

Related

How to access two separate Web APIs protected using Azure AD B2C from a web app

We have two separeate dotnet core apis(API1 & API2) that are protected using azure ad b2c. Both these apis are registered on the b2c tenant and have their scopes exposed.
We have a client web applicaiton that is to access the above protected apis. This web app has been registered as a applicaiton in b2c tenant and has api permissions set for the above apis with proper scopes defined.
We use MSAL.net with a signinpolicy to sign the user in to the web app.
the authentication call requires scopes to mentioned. So we add API1's scope in the call.
(note : one scope of a single resource can be added in a auth call shown below)
public void ConfigureAuth(IAppBuilder app)
{
// Required for Azure webapps, as by default they force TLS 1.2 and this project attempts 1.0
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
// ASP.NET web host compatible cookie manager
CookieManager = new SystemWebChunkingCookieManager()
});
app.UseOpenIdConnectAuthentication(
new OpenIdConnectAuthenticationOptions
{
// Generate the metadata address using the tenant and policy information
MetadataAddress = String.Format(Globals.WellKnownMetadata, Globals.Tenant, Globals.DefaultPolicy),
// These are standard OpenID Connect parameters, with values pulled from web.config
ClientId = Globals.ClientId,
RedirectUri = Globals.RedirectUri,
PostLogoutRedirectUri = Globals.RedirectUri,
// Specify the callbacks for each type of notifications
Notifications = new OpenIdConnectAuthenticationNotifications
{
RedirectToIdentityProvider = OnRedirectToIdentityProvider,
AuthorizationCodeReceived = OnAuthorizationCodeReceived,
AuthenticationFailed = OnAuthenticationFailed,
},
// Specify the claim type that specifies the Name property.
TokenValidationParameters = new TokenValidationParameters
{
NameClaimType = "name",
ValidateIssuer = false
},
// Specify the scope by appending all of the scopes requested into one string (separated by a blank space)
Scope = $"openid profile offline_access {Globals.ReadTasksScope} {Globals.WriteTasksScope}",
// ASP.NET web host compatible cookie manager
CookieManager = new SystemWebCookieManager()
}
);
}
The OnAuthorizationCodeRecieved method in Startup.Auth.cs recieved the code recieved as a result of above auth call and uses it to get a access token based on the scopes provided and stores it in the cache. shown below
private async Task OnAuthorizationCodeReceived(AuthorizationCodeReceivedNotification notification)
{
try
{
/*
The `MSALPerUserMemoryTokenCache` is created and hooked in the `UserTokenCache` used by `IConfidentialClientApplication`.
At this point, if you inspect `ClaimsPrinciple.Current` you will notice that the Identity is still unauthenticated and it has no claims,
but `MSALPerUserMemoryTokenCache` needs the claims to work properly. Because of this sync problem, we are using the constructor that
receives `ClaimsPrincipal` as argument and we are getting the claims from the object `AuthorizationCodeReceivedNotification context`.
This object contains the property `AuthenticationTicket.Identity`, which is a `ClaimsIdentity`, created from the token received from
Azure AD and has a full set of claims.
*/
IConfidentialClientApplication confidentialClient = MsalAppBuilder.BuildConfidentialClientApplication(new ClaimsPrincipal(notification.AuthenticationTicket.Identity));
// Upon successful sign in, get & cache a token using MSAL
AuthenticationResult result = await confidentialClient.AcquireTokenByAuthorizationCode(Globals.Scopes, notification.Code).ExecuteAsync();
}
catch (Exception ex)
{
throw new HttpResponseException(new HttpResponseMessage
{
StatusCode = HttpStatusCode.BadRequest,
ReasonPhrase = $"Unable to get authorization code {ex.Message}.".Replace("\n", "").Replace("\r", "")
});
}
}
This access token is then used in the TasksController to call AcquireTokenSilent which retrieves the access token from the cache, which is then used in the api call.
public async Task<ActionResult> Index()
{
try
{
// Retrieve the token with the specified scopes
var scope = new string[] { Globals.ReadTasksScope };
IConfidentialClientApplication cca = MsalAppBuilder.BuildConfidentialClientApplication();
var accounts = await cca.GetAccountsAsync();
AuthenticationResult result = await cca.AcquireTokenSilent(scope, accounts.FirstOrDefault()).ExecuteAsync();
HttpClient client = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, apiEndpoint);
// Add token to the Authorization header and make the request
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", result.AccessToken);
HttpResponseMessage response = await client.SendAsync(request);
// Handle the response
switch (response.StatusCode)
{
case HttpStatusCode.OK:
String responseString = await response.Content.ReadAsStringAsync();
JArray tasks = JArray.Parse(responseString);
ViewBag.Tasks = tasks;
return View();
case HttpStatusCode.Unauthorized:
return ErrorAction("Please sign in again. " + response.ReasonPhrase);
default:
return ErrorAction("Error. Status code = " + response.StatusCode + ": " + response.ReasonPhrase);
}
}
catch (MsalUiRequiredException ex)
{
/*
If the tokens have expired or become invalid for any reason, ask the user to sign in again.
Another cause of this exception is when you restart the app using InMemory cache.
It will get wiped out while the user will be authenticated still because of their cookies, requiring the TokenCache to be initialized again
through the sign in flow.
*/
return new RedirectResult("/Account/SignUpSignIn?redirectUrl=/Tasks");
}
catch (Exception ex)
{
return ErrorAction("Error reading to do list: " + ex.Message);
}
}
The issue is the code recieved by the OnAuthorizationCodeRecieved method can only be used to get the access token for API1 since its scope was mentioned in auth call. When trying to get access token for API2 it returns null.
Question : How to configure the web app so that it is able to access multiple protected apis?
Please suggest.
The code can be found from the sample https://github.com/Azure-Samples/active-directory-b2c-dotnet-webapp-and-webapi
A single access token can only contain scopes for a single audience.
You have 2 options:
Combine both services into a single app registration and expose different scopes.
Request multiple tokens - one per service. If your SSO policy is configured correctly in B2C, this should happen silently unbeknownst to the user.
I recommend using option 1 if you own both services (which it sounds like you do). A few tips related to this option.
When declaring the scopes in the combined app registration, use the dot-syntax {LogicalService}.{Operation}. If you do this, the scopes will be grouped by logical service within the Azure portal.
Make sure you are validating scopes in your service. Validating only the audience is not good enough and would allow an attacker to make lateral movements with a token bound for another service.

How to get user's basic details from MS Graph API

I am trying to get full name of a user using MS Graph API. The code is not working with delegated permission User.ReadBasic.All while working with App permission of User.Read.All
code is:
public static async Task<string> GetAccessToken()
{
string authorityUri = $"https://login.microsoftonline.com/{tenantid}";
AuthenticationContext authContext = new AuthenticationContext(authorityUri);
string resourceUrl = "https://graph.microsoft.com";
ClientCredential creds = new ClientCredential(ConfigHelper.ClientId, ConfigHelper.AppKey);
AuthenticationResult authResult = await authContext.AcquireTokenAsync(resourceUrl, creds);
return authResult.AccessToken;
}
public static async Task<GraphServiceClient> GetGraphClient()
{
GraphServiceClient graphServiceClient = new GraphServiceClient(new DelegateAuthenticationProvider(
async (requestMessage) =>
{
string accessToken = await GetAccessToken();
if (!string.IsNullOrEmpty(accessToken))
{
requestMessage.Headers.Authorization = new AuthenticationHeaderValue("bearer", accessToken);
}
}));
return graphServiceClient;
}
Error is
Microsoft.Graph.ServiceException: Code: Authorization_RequestDenied
Message: Insufficient privileges to complete the operation. Blockquote
I am not sure why this is happening.
Edited:
private static async Task<string> GetAccessToken()
{
string signedInUserID = ClaimsPrincipal.Current.FindFirst(ClaimTypes.NameIdentifier).Value;
string tenantID = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/tenantid").Value;
string userObjectID = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier").Value;
string resourceUrl = "https://graph.microsoft.com";
//// get a token for the Graph without triggering any user interaction (from the cache, via multi-resource refresh token, etc)
ClientCredential clientcred = new ClientCredential(ConfigHelper.ClientId, ConfigHelper.AppKey);
//// initialize AuthenticationContext with the token cache of the currently signed in user, as kept in the app's database
AuthenticationContext authenticationContext = new AuthenticationContext($"https://login.microsoftonline.com/{tenantid}") ;
AuthenticationResult authenticationResult = await authenticationContext.AcquireTokenSilentAsync(resourceUrl, clientcred, new UserIdentifier(userObjectID, UserIdentifierType.UniqueId));
return authenticationResult.AccessToken;
}
Well, you are using Client Credentials Grant Flow, expecting delegated permissions to be applied to a scenario where there is no user.
The token you get is for the app acting purely as itself, which means only Application Permissions will be applied. Delegated permissions are only applied when there is a user context.
Your options:
Use Application permissions
Use a flow like Authorization Code Grant Flow to get a delegated access token
You get a refresh token too when you get a token in this way, which you can use to get a new access token for this user whenever you want (+ a new refresh token)
Though certain situations like the user resetting their password will cause the refresh token to be revoked

Failed to get AccessToken via authorization code using MSAL 1.1.0-preview in asp.net core

I followed official steps as below to try the scenario "web app calling a Web API in Azure Ad B2C", the only difference is I am using Asp.Net core. I am using AuthorizationCode to get the access token, but it always returns with id token and NULL access token.
Create an Azure AD B2C tenant.
Register a web api.
Register a web app.
Set up policies.
Grant the web app permissions to use the web api.
My code:
app.UseOpenIdConnectAuthentication(new OpenIdConnectOptions
{
AuthenticationScheme = OpenIdConnectDefaults.AuthenticationScheme,
AutomaticChallenge = true,
ClientId = aadB2cSettings.ClientId,
MetadataAddress = $"{aadB2cSettings.Instance}{aadB2cSettings.Tenant}/v2.0/.well-known/openid-configuration?p={aadB2cSettings.B2cSignUpOrSignInPolicy}",
PostLogoutRedirectUri = aadB2cSettings.RedirectUrl,
ResponseType = OpenIdConnectResponseType.CodeIdToken,
TokenValidationParameters = new TokenValidationParameters
{
NameClaimType = "name"
},
Events = new OpenIdConnectEvents
{
OnAuthorizationCodeReceived = async context =>
{
var authCode = context.TokenEndpointRequest.Code;
var b2cAuthority = $"{aadB2cSettings.Instance}tfp/{aadB2cSettings.Tenant}/{aadB2cSettings.B2cSignUpOrSignInPolicy}/v2.0/.well-known/openid-configuration";
var cca = new ConfidentialClientApplication(
aadB2cSettings.ClientId,
b2cAuthority,
aadB2cSettings.RedirectUrl,
new ClientCredential(aadB2cSettings.ClientSecret),
new TokenCache(),
null);
try
{
var authResult = await cca.AcquireTokenByAuthorizationCodeAsync(authCode, new[] { "https://hulab2c.onmicrosoft.com/b2cdemo/all" });
context.HandleCodeRedemption(authResult.AccessToken, authResult.IdToken);
}
catch (Exception ex)
{
throw ex;
}
}
},
Used fiddler to capture the request, it is:
POST
https://login.microsoftonline.com/hulab2c.onmicrosoft.com/oauth2/v2.0/token?p=b2c_1_signuporsignin
HTTP/1.1
Request Body:
client_id=1ff91f47-08ee-4973-83f4-379ad7e0679c&client_info=1&client_secret=......&scope=https%3A%2F%2Fhulab2c.onmicrosoft.com%2Fb2cdemo%2Fall+offline_access+openid+profile&grant_type=authorization_code&code=......&redirect_uri=https%3A%2F%2Flocalhost%3A44383%2F
Return:
{"id_token":"......","token_type":"Bearer","not_before":1494494423,"client_info":"......","scope":""}
So only id token, no access token. But we should get access token here, right?
Finally found out my failure reason: the request to get AuthorizationCode doesn't contain the target scope. Reflect in code, for OpenIdConnectOption in aspnetcore, the Scope parameter is readonly and its default value is "opened profile".
Scope is readonly in OpenIdConnectOption
So the default authorization code request sent is:
GET
https://login.microsoftonline.com/hulab2c.onmicrosoft.com/oauth2/v2.0/authorize?p=b2c_1_signuporsignin&client_id=7f865ca0-271e-4f27-be21-6f0072fe3ad7&redirect_uri=https%3A%2F%2Flocalhost%3A44355%2Fsignin-oidc&response_type=code%20id_token&scope=openid%20profile&response_mode=form_post&nonce=......
HTTP/1.1
Thus, using this authorization code in response to get token, even we set right scope in the token request, we still can't get the access code but only id token, because the provide authorization code is only for "openid profile".
To fix this, we need to add target web api scope into the authorization code as well. Here is the how-to-fix code:
Events = new OpenIdConnectEvents
{
OnRedirectToIdentityProvider = context =>
{
context.ProtocolMessage.Scope += $" offline_access {myapiscope}";
return Task.FromResult(0);
},
......
}
In AspNet, we don't need to do this because its scope is not readonly as aspnetcore and can be set directly:
new OpenIdConnectAuthenticationOptions
{
......
Scope = $"openid profile offline_access {ReadTasksScope} {WriteTasksScope}"
}
https://github.com/Azure-Samples/active-directory-b2c-dotnet-webapp-and-webapi/issues/4 Microsoft have reproduced the issue and working on fix

OpenIdConnectResponseTypes has codeidtoken ,idtoken and it doesnt contain code as response type

OpenIdConnectResponseTypes has codeidtoken ,idtoken and it doesnt contain code as response type. Does UseOpenIdConnectAuthentication in OWIN support Authorization Code grant? By default it sets the responsetype as Code IDToken. Can someone share the sample for Authorization code grant using OWIN ?
From source code of Katana (below code could be found in OpenIDConnectAuthenticationHandler.AuthenticateCoreAsync method):
// code is only accepted with id_token, in this version, hence check for code is inside this if
// OpenIdConnect protocol allows a Code to be received without the id_token
if (string.IsNullOrWhiteSpace(openIdConnectMessage.IdToken))
{
_logger.WriteWarning("The id_token is missing.");
return null;
}
Above code shows Microsoft.Owin.Security.OpenIdConnect library doesn't support Authorization Code grant . Though not directly supported, you can also use the hybrid flow , but it's up to you to implement the token request part , please refer to below code which use code to exchange the access token for resource protected by azure ad :
app.UseOpenIdConnectAuthentication(
new OpenIdConnectAuthenticationOptions
{
ClientId = clientId,
Authority = Authority,
PostLogoutRedirectUri = postLogoutRedirectUri,
Notifications = new OpenIdConnectAuthenticationNotifications()
{
//
// If there is a code in the OpenID Connect response, redeem it for an access token and refresh token, and store those away.
//
AuthorizationCodeReceived = async (context) =>
{
var code = context.Code;
// Create a Client Credential Using an Application Key
ClientCredential credential = new ClientCredential(clientId, appKey);
string userObjectID = context.AuthenticationTicket.Identity.FindFirst(
"http://schemas.microsoft.com/identity/claims/objectidentifier").Value;
AuthenticationContext authContext = new AuthenticationContext(Authority, new NaiveSessionCache(userObjectID));
AuthenticationResult result = await authContext.AcquireTokenByAuthorizationCodeAsync(
code, new Uri(HttpContext.Current.Request.Url.GetLeftPart(UriPartial.Path)), credential, graphResourceId);
}
}
}

Graph API is not working via project code but same URL is working via AD Graph Explorer

I have download a MVC application from Git for AAD graph API. I ran this application but each time i am not getting expected result.
To find the error i run same api using postman and generated token below was the response.
{
"odata.error": {
"code": "Request_ResourceNotFound",
"message": {
"lang": "en",
"value": "Resource not found for the segment 'me'."
}
}
}
I am using below Get URL-
https://graph.windows.net/XXXXX/me?api-version=1.6
Also, to verify is it working with AAD Grapg api explorer. After log in everything is working fine.
Below is my code to call Grapg API-
// Get the access token from the cache
string userObjectID =
ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier")
.Value;
string authority = String.Format(CultureInfo.InvariantCulture, aadInstance, tenant);
//AuthenticationContext authContext = new AuthenticationContext(authority,
// new NaiveSessionCache(userObjectID));
ClientCredential credential = new ClientCredential(clientId, appKey);
AuthenticationContext authContext = new AuthenticationContext(authority, true);
result = await authContext.AcquireTokenAsync(graphResourceId.ToString(), credential);
var Token = result.AccessToken;
//// AcquireTokenSilentAsync
//result = await authContext.AcquireTokenSilentAsync(graphResourceId, credential,
// new UserIdentifier(userObjectID, UserIdentifierType.UniqueId));
// Call the Graph API manually and retrieve the user's profile.
string requestUrl = String.Format(
CultureInfo.InvariantCulture,
graphUserUrl,
HttpUtility.UrlEncode(tenantId));
HttpClient client = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, requestUrl);
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", result.AccessToken);
HttpResponseMessage response = await client.SendAsync(request);
// Return the user's profile in the view.
if (response.IsSuccessStatusCode)
{
string responseString = await response.Content.ReadAsStringAsync();
profile = JsonConvert.DeserializeObject<UserProfile>(responseString);
}
Could you guys please tell me what is the problem with my code. Why it is working on AAD explorer not with Localhost.
To request the me endpoint of Azure AD Graph REST, we need to use the delegate token which represents the sign-in user.
The code above you acquire token using the Client Credential flow is request the access token which represents for the application which doesn't contain the info of sign-in user.
To achieve this in the MVC application, we need to acquire the token after you get the authorization code when users login. Next time, we can acquire the token from the token cache based on the login user.
Here is the code for your reference( code sample from here):
result = await authContext.AcquireTokenSilentAsync(graphResourceId, credential,
new UserIdentifier(userObjectID, UserIdentifierType.UniqueId));

Resources