Microsoft Graph API and Outlook API in a Single App - outlook

I have an app using MSAL connecting to MS Graph and have been able to use the API. There are couple Outlook APIs such as https://msdn.microsoft.com/en-us/office/office365/api/calendar-rest-operations#GetRoomLists, FindRoomLists currently not available in Graph.
I have the need to use both these APIs in a single app? I read a similar question on Stack Overflow and it mentioned, a Token cannot be used for both Graph and Outlook. I did try and it did not work.
Any suggestions? Is my path to quit using Graph and go to Outlook API?

MSAL will look up the cache and return any cached token which match with the requirement. If such access tokens are expired or no suitable access tokens are present, but there is an associated refresh token(need offline_access scope), MSAL will automatically use that to get a new access token and return it transparently.
For example, if you use MSAL to redeem the authorization code into an access token for microsoft graph, in openid connect owin middleware :
AuthorizationCodeReceived = async (context) =>
{
var code = context.Code;
string signedInUserID = context.AuthenticationTicket.Identity.FindFirst(ClaimTypes.NameIdentifier).Value;
TokenCache userTokenCache = new MSALSessionCache(signedInUserID,
context.OwinContext.Environment["System.Web.HttpContextBase"] as HttpContextBase).GetMsalCacheInstance();
ConfidentialClientApplication cca =
new ConfidentialClientApplication(clientId, redirectUri, new ClientCredential(appKey), userTokenCache,null);
string[] scopes = { "Mail.Read" };
try
{
AuthenticationResult result = await cca.AcquireTokenByAuthorizationCodeAsync(code, scopes);
}
catch (Exception eee)
{
}
},
With scope Mail.Read , you could get an access token for Microsoft Graph, for the purpose of reading the user's mailbox .Now if you want to call outlook mail rest api in a controller/action , you could use scope: https://outlook.office.com/mail.read , MSAL will acquire token for outlook mail rest api using cached refresh token :
// try to get token silently
string signedInUserID = ClaimsPrincipal.Current.FindFirst(ClaimTypes.NameIdentifier).Value;
TokenCache userTokenCache = new MSALSessionCache(signedInUserID, this.HttpContext).GetMsalCacheInstance();
ConfidentialClientApplication cca = new ConfidentialClientApplication(clientId, redirectUri,new ClientCredential(appKey), userTokenCache, null);
if (cca.Users.Count() > 0)
{
string[] scopes = { "https://outlook.office.com/mail.read" };
try
{
AuthenticationResult result = await cca.AcquireTokenSilentAsync(scopes,cca.Users.First());
}
catch (MsalUiRequiredException)
{
try
{// when failing, manufacture the URL and assign it
string authReqUrl = await WebApp.Utils.OAuth2RequestManager.GenerateAuthorizationRequestUrl(scopes, cca, this.HttpContext, Url);
ViewBag.AuthorizationRequest = authReqUrl;
}
catch (Exception ee)
{
}
}
}
else
{
}
Please refer to code sample : Integrate Microsoft identity and the Microsoft Graph into a web application using OpenID Connect.

Related

How to implement Exchange online OAuth2.0 for unmanaged EWS API?

For managed EWS code, I have used to OAuth 2.0 to get token and it worked.
For unmanaged EWS, it is failing to connect to Exchange as an unauthorized error.
Below is the code to access unmanaged EWS.
How to make below code work with OAuth token instead of passing credentials as below?.
Binding = new ExchangeServiceBinding
{
Url = ServerUrl,
Credentials = new OAuthCredentials(token),
RequestServerVersionValue = new RequestServerVersion { Version = ExchangeVersionType.Exchange2007_SP1 },
ExchangeImpersonation = null
};
Above is not working as credential is asking of type ICredentials and it is not accepting token. Please help me.
Below is the code how I direct access managed EWS.
var authResult = await pca.AcquireTokenByUsernamePassword(ewsScopes, credential.UserName, credential.SecurePassword).ExecuteAsync();
configure the ExchangeService with the access token
ExchangeService = new ExchangeService();
ExchangeService.Url = new Uri(ServerUrl);
ExchangeService.Credentials = new OAuthCredentials(authResult.AccessToken);
One method i use (as I've never worked out how to override the WSDL classes) is if you modify the Reference.cs file that gets generated in the web references directory you can modify the GetWebResponse command (In this case the token is being passed via the credentials object password property but there a number of different approaches you can take here) eg
private String AnchorMailbox;
private bool oAuth;
protected override System.Net.WebResponse GetWebResponse(System.Net.WebRequest req)
{
if (xAnchorMailbox != null)
{
if (xAnchorMailbox != "")
{
req.Headers.Add("X-AnchorMailbox", AnchorMailbox);
}
}
if(req.Credentials is System.Net.NetworkCredential)
{
if(oAuth){
req.Headers.Add("Authorization", ("Bearer " + ((System.Net.NetworkCredential)req.Credentials).Password));
}
}
System.Net.HttpWebResponse
rep = (System.Net.HttpWebResponse)base.GetWebResponse(req);
return rep;
}

Application Permission support for Dynamics Customer Engagement Web API

We are planning to move from Organization Service to Common Data Service Web API so we could utilize OAuth 2.0 authentication instead of a service account which customer has some security concerns.
Once we did some prototype, we discovered that the Web API authentication is a little different from typical Graph API authentication. It only supports Delegated Permission. Thus a user credential must be presented for acquiring the access token.
Here is the Azure AD Graph API permission for CRM Web API:
Here is the code in acquiring the access token for the sample code at Web API Global Discovery Service Sample (C#)
string GlobalDiscoUrl = "https://globaldisco.crm.dynamics.com/";
AuthenticationContext authContext = new AuthenticationContext("https://login.microsoftonline.com", false);
UserCredential cred = new UserCredential(username, password);
AuthenticationResult authResult = authContext.AcquireToken(GlobalDiscoUrl, clientId, cred);
Here is another similar post Connect to Dynamics 365 Customer Engagement web services using OAuth although it is more than one year old.
Do you know when MS would support Application permission to completely eliminate the user from authentication? Or there is any particular reason to keep the user here. Thanks for any insights.
[Update 1]
With below answer from James, I did the modification for the code, here is my code
string clientId = "3f4b24d8-61b4-47df-8efc-1232a72c8817";
string secret = "xxxxx";
ClientCredential cred = new ClientCredential(clientId, secret);
string GlobalDiscoUrl = "https://globaldisco.crm.dynamics.com/";
AuthenticationContext authContext = new AuthenticationContext("https://login.microsoftonline.com/common", false);
AuthenticationResult authResult = authContext.AcquireToken(GlobalDiscoUrl, cred);
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", authResult.AccessToken);
client.Timeout = new TimeSpan(0, 2, 0);
client.BaseAddress = new Uri(GlobalDiscoUrl);
HttpResponseMessage response = client.GetAsync("api/discovery/v1.0/Instances", HttpCompletionOption.ResponseHeadersRead).Result;
if (response.IsSuccessStatusCode)
{
//Get the response content and parse it.
string result = response.Content.ReadAsStringAsync().Result;
JObject body = JObject.Parse(result);
JArray values = (JArray)body.GetValue("value");
if (!values.HasValues)
{
return new List<Instance>();
}
return JsonConvert.DeserializeObject<List<Instance>>(values.ToString());
}
else
{
throw new Exception(response.ReasonPhrase);
}
}
so I am able to acquire the access token, but it still could not access the global discovery services.
Here is what the access token looks like:
{
"aud": "https://globaldisco.crm.dynamics.com/",
"iss": "https://sts.windows.net/f8cdef31-a31e-4b4a-93e4-5f571e91255a/",
"iat": 1565802457,
"nbf": 1565802457,
"exp": 1565806357,
"aio": "42FgYEj59uDNtwvxTLnprU0NYt49AA==",
"appid": "3f4b24d8-61b4-47df-8efc-1232a72c8817",
"appidacr": "1",
"idp": "https://sts.windows.net/f8cdef31-a31e-4b4a-93e4-5f571e91255a/",
"tid": "f8cdef31-a31e-4b4a-93e4-5f571e91255a",
"uti": "w8uwKBSPM0y7tdsfXtAgAA",
"ver": "1.0"
}
By the way, we did already create the application user inside CRM by following the instruction.
Anything I am missing here?
[Update 2]
For WhoAmI request, there are different results. If I am using latest MSAL and with authority "https://login.microsoftonline.com/AzureADDirectoryID/oauth2/authorize", I would be able to get the correct result. If I am using MSAL with "https://login.microsoftonline.com/common/oauth2/authorize", it won't work, I would get unauthorized error. If I am using ADAL 2.29, it is not working for both authority. Here is the working code:
IConfidentialClientApplication app = ConfidentialClientApplicationBuilder.Create("3f4b24d8-61b4-47df-8efc-1232a72cxxxx")
.WithClientSecret("xxxxxx")
// .WithAuthority("https://login.microsoftonline.com/common/oauth2/authorize", false)
.WithAuthority("https://login.microsoftonline.com/3a984a19-7f55-4ea3-a422-2d8771067f87/oauth2/authorize", false)
.Build();
var authResult = app.AcquireTokenForClient(new String[] { "https://crmxxxxx.crm5.dynamics.com/.default" }).ExecuteAsync().Result;
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", authResult.AccessToken);
client.Timeout = new TimeSpan(0, 2, 0);
client.BaseAddress = new Uri("https://crm525842.api.crm5.dynamics.com/");
HttpResponseMessage response = client.GetAsync("api/data/v9.1/WhoAmI()", HttpCompletionOption.ResponseHeadersRead).Result;
if (response.IsSuccessStatusCode)
{
//Get the response content.
string result = response.Content.ReadAsStringAsync().Result;
Console.WriteLine(result);
}
else
{
throw new Exception(response.ReasonPhrase);
}
The documentation isn't the easiest to follow, but from what I understand you should start with Use OAuth with Common Data Service.
You then have two subtle options when registering your app. The second does not require the Access Dynamics 365/Common Data Service as organization users permission
Giving access to Common Data Service
If your app will be a client which allows the authenticated user to
perform operations, you must configure the application to have the
Access Dynamics 365 as organization users delegated permission.
Or
If your app will use Server-to-Server (S2S) authentication, this step
is not required. That configuration requires a specific system user
and the operations will be performed by that user account rather than
any user that must be authenticated.
This is elaborated further.
Connect as an app
Some apps you will create are not intended to be run interactively by
a user. ... In these cases you can create a special application user
which is bound to an Azure Active Directory registered application and
use either a key secret configured for the app or upload a X.509
certificate. Another benefit of this approach is that it doesn't
consume a paid license.
Register your app
When registering an app you follow many of the same steps ... with the
following exceptions:
You do not need to grant the Access Dynamics 365 as organization users permission.
You will still have a system user record in Dynamics to represent the application registration. This supports a range of basic Dynamics behaviours and allows you to apply Dynamics security to you app.
As opposed to a username and password you can then use the secret to connect.
string serviceUrl = "https://yourorg.crm.dynamics.com";
string clientId = "<your app id>";
string secret = "<your app secret>";
AuthenticationContext authContext = new AuthenticationContext("https://login.microsoftonline.com/common", false);
ClientCredential credential = new ClientCredential(clientId, secret);
AuthenticationResult result = authContext.AcquireToken(serviceUrl, credential);
string accessToken = result.AccessToken;
Or a certificate.
string CertThumbPrintId = "DC6C689022C905EA5F812B51F1574ED10F256FF6";
string AppID = "545ce4df-95a6-4115-ac2f-e8e5546e79af";
string InstanceUri = "https://yourorg.crm.dynamics.com";
string ConnectionStr = $#"AuthType=Certificate;
SkipDiscovery=true;url={InstanceUri};
thumbprint={CertThumbPrintId};
ClientId={AppID};
RequireNewInstance=true";
using (CrmServiceClient svc = new CrmServiceClient(ConnectionStr))
{
if (svc.IsReady)
{
...
}
}
You may also want to check out Build web applications using Server-to-Server (S2S) authentication which appears to be a similar (but different).
Use server-to-server (S2S) authentication to securely and seamlessly
communicate with Common Data Service with your web applications and
services. S2S authentication is the common way that apps registered on
Microsoft AppSource use to access the Common Data Service data of
their subscribers. ... Rather than user credentials, the application is authenticated based on a service principal identified by an Azure AD Object ID value which is stored in the application user record.
Aside; if you are currently using the Organization Service .NET object, that is being migrated to using the Web API internally.
Microsoft Dynamics CRM 2011 endpoint
The Dynamics 365 SDK assemblies will be updated to use the Web API.
This update will be fully transparent to you and any code written
using the SDK itself will be supported.

How to flow user Consent for a Web API to access MS Graph user profile in AAD V2 end point with MSAL library

I'm trying to build a feature where a client application retrieves the graph resources via WebAPI layer. The scenario has following applications:
Angular5 Client application
ASP.Net Core Web API
The Angular5 client application uses MSAL to authenticate against application (resisted as Converged application via apps.dev.microsoft.com registration application; AAD v2 endpoint).
The authentication flow defines the Web API as scope while login or getting access token
constructor() {
var logger = new Msal.Logger((logLevel, message, piiEnabled) =>
{
console.log(message);
},
{ level: Msal.LogLevel.Verbose, correlationId: '12345' });
this.app = new Msal.UserAgentApplication(
CONFIGSETTINGS.clientId,
null,
this.authCallback,
{
redirectUri: window.location.origin,
cacheLocation: 'localStorage',
logger: logger
}
);
}
public getAPIAccessToken() {
return this.app.acquireTokenSilent(CONFIGSETTINGS.scopes).then(
accessToken => {
return accessToken;
},
error => {
return this.app.acquireTokenSilent(CONFIGSETTINGS.scopes).then(
accessToken => {
return accessToken;
},
err => {
console.error(err);
}
);
}
);
}
Here scope is defined as scopes: ['api://<<guid of application>>/readAccess']. This is the exact value which was generated when I've registered the Web API in registeration portal. Also, the client application id is added as Pre-authorized applications .
The Web API layer (built in dotnet core -- and uses JwtBearer to validate the authentication), defines the API which internally fetches the graph resources (using HttpClient). To get the access token, I've used following code
public async Task<string> GetAccesToken(string resourceName)
{
var userAssertion = this.GetUserAssertion();
string upn = GetLoggedInUpn();
var userTokenCache = new SessionTokenCache(upn, new Microsoft.Extensions.Caching.Memory.MemoryCache(new MemoryCacheOptions())).GetCacheInstance();
string msGraphScope = "https://graph.microsoft.com/User.Read";
string authority = string.Format("https://login.microsoftonline.com/{0}/v2.0", this.authConfig.TenantId);
ConfidentialClientApplication clientApplication = new ConfidentialClientApplication(this.authConfig.ClientId, authority, new ClientCredential(this.authConfig.AppKey), userTokenCache, null);
var result = await clientApplication.AcquireTokenOnBehalfOfAsync(new string[] { msGraphScope }, userAssertion);
return result != null ? result.AccessToken : null;
}
private UserAssertion GetUserAssertion()
{
string token = this.httpContextAccessor.HttpContext.Request.Headers["Authorization"];
string upn = GetLoggedInUpn();
if (token.StartsWith("Bearer", true, CultureInfo.InvariantCulture))
{
token = token.Trim().Substring("Bearer".Length).Trim();
return new UserAssertion(token, "urn:ietf:params:oauth:grant-type:jwt-bearer");
}
else
{
throw new Exception($"ApiAuthService.GetUserAssertion() failed: Invalid Authorization token");
}
}
Note here, The method AcquireTokenOnBehalfOfAsync is used to get the access token using graph scope. However it throws the following exception:
AADSTS65001: The user or administrator has not consented to use the application with ID '<>' named '<>'. Send an interactive authorization request for this user and resource.
I'm not sure why the of-behalf flow for AAD v2 is not working even when client application uses the Web API as scope while fetching access token and Web API registers the client application as the pre-authorized application.
Note - I've tried using the other methods of ConfidentialClientApplication but even those did not work.
Can someone please point out how the above flow can work without providing the admin consent on Web API?
I've been trying to figure this out for weeks! My solution isn't great (it requires the user to go through the consent process again for the Web API), but I'm not sure that's entirely unexpected. After all, either the Admin has to give consent for the Web API to access the graph for the user, or the user has to give consent.
Anyway, the key was getting consent from the user, which of course the Web API can't do since it has no UI. However, ConfidentialClientApplication will tell you the URL that the user has to visit with GetAuthorizationRequestUrlAsync.
Here's a snippet of the code that I used to get it working (I'm leaving out all the details of propagating the url back to the webapp, but you can check out https://github.com/rlittletht/msal-s2s-ref for a working example.)
async Task<string> GetAuthenticationUrlForConsent(ConfidentialClientApplication cca, string []graphScopes)
{
// if this throws, just let it throw
Uri uri = await cca.GetAuthorizationRequestUrlAsync(graphScopes, "", null);
return uri.AbsoluteUri;
}
async Task<string> GetAccessTokenForGraph()
{
// (be sure to use the redirectUri here that matches the Web platform
// that you added to your WebApi
ConfidentialClientApplication cca =
new ConfidentialClientApplication(Startup.clientId,
"http://localhost/webapisvc/auth.aspx",
new ClientCredential(Startup.appKey), null, null);
string[] graphScopes = {"https://graph.microsoft.com/.default"};
UserAssertion userAssertion = GetUserAssertion();
AuthenticationResult authResult = null;
try
{
authResult = await cca.AcquireTokenOnBehalfOfAsync(graphScopes, userAssertion);
}
catch (Exception exc)
{
if (exc is Microsoft.Identity.Client.MsalUiRequiredException
|| exc.InnerException is Microsoft.Identity.Client.MsalUiRequiredException)
{
// We failed because we don't have consent from the user -- even
// though they consented for the WebApp application to access
// the graph, they also need to consent to this WebApi to grant permission
string sUrl = await GetAuthenticationUrlForConsent(cca, graphScopes);
// you will need to implement this exception and handle it in the callers
throw new WebApiExceptionNeedConsent(sUrl, "WebApi does not have consent from the user to access the graph on behalf of the user", exc);
}
// otherwise, just rethrow
throw;
}
return authResult.AccessToken;
}
One of the things that I don't like about my solution is that it requires that I add a "Web" platform to my WebApi for the sole purpose of being able to give it a redirectUri when I create the ConfidentialClientApplication. I wish there was some way to just launch the consent workflow, get the user consent, and then just terminate the flow (since I don't need a token to be returned to me -- all I want is consent to be granted).
But, I'm willing to live with the extra clunky step since it actually gets consent granted and now the API can call the graph on behalf of the user.
If someone has a better, cleaner, solution, PLEASE let us know! This was incredibly frustrating to research.

Openiddict guidance related to external login

I have a mobile app that talks to a backend web API (core 2.0). Presently I have the API configured to use Opendidict with Facebook integration based on the configuration listed below.
public static IServiceCollection AddAuthentication(this IServiceCollection services, AppSettings settings)
{
services.AddOpenIddict<int>(options =>
{
options.AddEntityFrameworkCoreStores<RouteManagerContext>();
options.AddMvcBinders();
options.EnableAuthorizationEndpoint("/auth/authorize");
options.EnableTokenEndpoint("/auth/token");
options.AllowAuthorizationCodeFlow();
options.AllowImplicitFlow();
options.AllowPasswordFlow();
options.AllowRefreshTokenFlow();
options.SetAccessTokenLifetime(TimeSpan.FromMinutes(1));
options.SetRefreshTokenLifetime(TimeSpan.FromMinutes(20160));
options.DisableHttpsRequirement();
options.AddEphemeralSigningKey();
});
services.AddAuthentication()
.AddFacebook(o => { o.ClientId = settings.FacebookAppID; o.ClientSecret = settings.FacebookAppSecret; })
.AddOAuthValidation();
return services;
}
The password flow works perfectly when they want to use local account. What I'm struggling with is how to return the access/refresh token after successfully authenticating with Facebook. I have the standard account controller with ExternalLogin and ExternalLoginCallback which also works perfectly as I'm able to successfully login and get the local user account it's tied to and signed in.
In my mind, the user clicks facebook login, which calls ExternalLogincallBack, which logs in the user. After that all I want to do is return the access/refresh token just like the password flow.
When I try to use the ImplicitFlow by providing the implicit flow arguments in the redirect (/auth/authorize?...) from ExternalLoginCallback, I can get the access token, but no refresh token even if I specify the offline_scope. From what I read, it seems the implicit flow doesn't support refresh so I tried code flow.
When using the CodeFlow, I can get the code token from the redirect to "/auth/authorize" but can't figure out how to call into the token endpoint from the authorize endpoint to return the access/refresh token directly to the client app. Do I just need to return the code to the client and have them make another call to post to the token endpoint to get access/refresh tokens?
This doesn't feel correct and I'm stumped. Seems like I should be able to just return the access/refresh token after I've signed in externally just like what happens with password flow. Any help would be greatly appreciated as I've been struggling with this for several days.
[HttpGet("~/auth/authorize")]
public async Task<IActionResult> Authorize(OpenIdConnectRequest request)
{
if (!User.Identity.IsAuthenticated)
{
// If the client application request promptless authentication,
// return an error indicating that the user is not logged in.
if (request.HasPrompt(OpenIdConnectConstants.Prompts.None))
{
var properties = new AuthenticationProperties(new Dictionary<string, string>
{
[OpenIdConnectConstants.Properties.Error] = OpenIdConnectConstants.Errors.LoginRequired,
[OpenIdConnectConstants.Properties.ErrorDescription] = "The user is not logged in."
});
// Ask OpenIddict to return a login_required error to the client application.
return Forbid(properties, OpenIdConnectServerDefaults.AuthenticationScheme);
}
return Challenge();
}
// Retrieve the profile of the logged in user.
var user = await _userManager.GetUserAsync(User);
if (user == null)
{
return BadRequest(new
{
Error = OpenIdConnectConstants.Errors.ServerError,
ErrorDescription = "An internal error has occurred"
});
}
// Create a new authentication ticket.
var ticket = await CreateTicketAsync(request, user);
// Returning a SignInResult will ask OpenIddict to issue the appropriate access/identity tokens.
return SignIn(ticket.Principal, ticket.Properties, ticket.AuthenticationScheme);
}
private async Task<AuthenticationTicket> CreateTicketAsync(OpenIdConnectRequest request, ApplicationUser user, AuthenticationProperties properties = null)
{
// Create a new ClaimsPrincipal containing the claims that will be used to create an id_token, a token or a code.
var principal = await _signInManager.CreateUserPrincipalAsync(user);
// Create a new authentication ticket holding the user identity.
var ticket = new AuthenticationTicket(principal, properties, OpenIdConnectServerDefaults.AuthenticationScheme);
if (!request.IsRefreshTokenGrantType())
{
// Set the list of scopes granted to the client application.
// Note: the offline_access scope must be granted to allow OpenIddict to return a refresh token.
ticket.SetScopes(new[]
{
OpenIdConnectConstants.Scopes.OpenId,
OpenIdConnectConstants.Scopes.Email,
OpenIdConnectConstants.Scopes.Profile,
OpenIdConnectConstants.Scopes.OfflineAccess,
OpenIddictConstants.Scopes.Roles
}.Intersect(request.GetScopes()));
}
ticket.SetResources("RouteManagerAPI");
// Note: by default, claims are NOT automatically included in the access and identity tokens.
// To allow OpenIddict to serialize them, you must attach them to a destination, that specifies
// whether they should be included in access tokens, in identity tokens or in both.
foreach (var claim in ticket.Principal.Claims)
{
// Never include the security stamp in the access and identity tokens, as it's a secret value.
if (claim.Type == _identityOptions.Value.ClaimsIdentity.SecurityStampClaimType)
{
continue;
}
var destinations = new List<string>
{
OpenIdConnectConstants.Destinations.AccessToken
};
// Only add the iterated claim to the id_token if the corresponding scope was granted to the client application.
// The other claims will only be added to the access_token, which is encrypted when using the default format.
if ((claim.Type == OpenIdConnectConstants.Claims.Name && ticket.HasScope(OpenIdConnectConstants.Scopes.Profile)) ||
(claim.Type == OpenIdConnectConstants.Claims.Email && ticket.HasScope(OpenIdConnectConstants.Scopes.Email)) ||
(claim.Type == OpenIdConnectConstants.Claims.Role && ticket.HasScope(OpenIddictConstants.Claims.Roles)))
{
destinations.Add(OpenIdConnectConstants.Destinations.IdentityToken);
}
claim.SetDestinations(destinations);
}
return ticket;
}
When I try to use the CodeFlow, I can get the code token but can't figure out how to call into the token endpoint from the authorize endpoint to return the access/refresh token directly to the client app. Do I just need to return the code to the client and have them make another call to post to the token endpoint to get access/refresh tokens?
That's exactly what you're supposed to do as the code flow is a 2-part process: once your mobile apps has an authorization code, it must redeem it using a simple HTTP call to the token endpoint to get an access token and a refresh token.

Aspnet core web api protected with Azure

I have a web api in my organization built with aspnet core. We want to publish that api to be consumed by an android app, a mvc5 app and an aspnet core mvc6 app. How can I configure the web api in azure so that the apps that consume it don't ask to login. The web apps, are already protected with azure, but when I protect the web api with azure I get a 401 when I make a request to it. I don't know how to configure the app in azure or the code I must configure in the api. I've read a lot but I don't find a way to acomplish this. All I want is to login in my web app, and the web app starts to ask data to the web api through ajax. I should send in the ajax request some sort of bareer token, but i don`t know what config i must do in azure and in the apps. I hope you can help me.
After you protected the web API with Azure AD, we need to send to access token with request for the web API for authorization. And we can get the access token when the users call the web API from web app. Here is the code to acquire the token in the web app for your reference:
public async Task<IActionResult> Index()
{
AuthenticationResult result = null;
List<TodoItem> itemList = new List<TodoItem>();
try
{
string userObjectID = (User.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier"))?.Value;
AuthenticationContext authContext = new AuthenticationContext(Startup.Authority, new NaiveSessionCache(userObjectID, HttpContext.Session));
ClientCredential credential = new ClientCredential(Startup.ClientId, Startup.ClientSecret);
result = await authContext.AcquireTokenSilentAsync(Startup.TodoListResourceId, credential, new UserIdentifier(userObjectID, UserIdentifierType.UniqueId));
//
// Retrieve the user's To Do List.
//
HttpClient client = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, TodoListBaseAddress + "/api/todolist");
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", result.AccessToken);
HttpResponseMessage response = await client.SendAsync(request);
//
// Return the To Do List in the view.
//
if (response.IsSuccessStatusCode)
{
List<Dictionary<String, String>> responseElements = new List<Dictionary<String, String>>();
JsonSerializerSettings settings = new JsonSerializerSettings();
String responseString = await response.Content.ReadAsStringAsync();
responseElements = JsonConvert.DeserializeObject<List<Dictionary<String, String>>>(responseString, settings);
foreach (Dictionary<String, String> responseElement in responseElements)
{
TodoItem newItem = new TodoItem();
newItem.Title = responseElement["title"];
newItem.Owner = responseElement["owner"];
itemList.Add(newItem);
}
return View(itemList);
}
else
{
//
// If the call failed with access denied, then drop the current access token from the cache,
// and show the user an error indicating they might need to sign-in again.
//
if (response.StatusCode == System.Net.HttpStatusCode.Unauthorized)
{
var todoTokens = authContext.TokenCache.ReadItems().Where(a => a.Resource == Startup.TodoListResourceId);
foreach (TokenCacheItem tci in todoTokens)
authContext.TokenCache.DeleteItem(tci);
ViewBag.ErrorMessage = "UnexpectedError";
TodoItem newItem = new TodoItem();
newItem.Title = "(No items in list)";
itemList.Add(newItem);
return View(itemList);
}
}
}
catch (Exception ee)
{
if (HttpContext.Request.Query["reauth"] == "True")
{
//
// Send an OpenID Connect sign-in request to get a new set of tokens.
// If the user still has a valid session with Azure AD, they will not be prompted for their credentials.
// The OpenID Connect middleware will return to this controller after the sign-in response has been handled.
//
return new ChallengeResult(OpenIdConnectDefaults.AuthenticationScheme);
}
//
// The user needs to re-authorize. Show them a message to that effect.
//
TodoItem newItem = new TodoItem();
newItem.Title = "(Sign-in required to view to do list.)";
itemList.Add(newItem);
ViewBag.ErrorMessage = "AuthorizationRequired";
return View(itemList);
}
//
// If the call failed for any other reason, show the user an error.
//
return View("Error");
}
And below is the code sample which use JwtBearerAppBuilderExtensions to add OpenIdConnect Bearer authentication capabilities to an HTTP application pipeline for the web API to verify the token:
public class Startup
{
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
// Add the console logger.
loggerFactory.AddConsole(LogLevel.Debug);
// Configure the app to use Jwt Bearer Authentication
app.UseJwtBearerAuthentication(new JwtBearerOptions
{
AutomaticAuthenticate = true,
AutomaticChallenge = true,
Authority = String.Format(Configuration["AzureAd:AadInstance"], Configuration["AzureAD:Tenant"]),
Audience = Configuration["AzureAd:Audience"],
});
}
}
The full code sample you can refer here.
Note: to run this sample successfully, we need to modify the Title and Owner to lowercase title, owner in the ToDoController of web app:
foreach (Dictionary<String, String> responseElement in responseElements)
{
TodoItem newItem = new TodoItem();
newItem.Title = responseElement["title"];
newItem.Owner = responseElement["owner"];
itemList.Add(newItem);
}
You can use Azure OpenIdConnect for federated authentication. A good article from microsoft below -
Calling a web API in a web app using Azure AD and OpenID Connect

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