Confusion using JWT when calling API - c#

I wrote an ASP.NET Core 3.1 API which uses the JWTBearer authentication system. This system works well when I call the API from Postman, but I can't figure out how to call it throught my own application or ASP.NET Core 3.1 MVC Website. Here is the configuration of the API :
API Configuration :
In the Startup.cs ConfigrationServices method I added this classical piece of code :
services.AddAuthentication(x =>
{
x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(x =>
{
x.RequireHttpsMetadata = true;
x.SaveToken = true;
x.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuerSigningKey = true,
IssuerSigningKey = new SymmetricSecurityKey(key),
ValidateIssuer = false,
ValidateAudience = false,
ValidateLifetime = true,
ClockSkew = TimeSpan.FromMinutes(5),
};
});
Then I added the middleware app.UseAuthentication(); to the Configure method.
Now I have a UsersController.cs with a SignIn method which returns a JWT as string if the credentials are corrects.
Finally, I added a simple GetUsers() method with an [Authorize] tag to test the JWT authentication as following :
// GET: api/Users
[Authorize(Roles = "Administrator")]
[HttpGet]
public async Task<ActionResult<IEnumerable<User>>> GetUsers()
{
return await _context.Users.ToListAsync();
}
Throught Postman, everything works fine. I call the api/Users/SignIn url in POST passing my credentials as JSON. I get back my token in response with the 200 StatusCode.
Then I call the api/Users in GET passing the JWT previously obtained to the Postman settings Authorization > Type : Bearer Token. My API returns a successful code with all the data I asked for. Everything works as expected at the API side.
MVC Website Configuration :
To simplify the discussion with the API, I wrote a Class Library with a ClientService.cs class.
Int the ClientService.cs, I have this simplified piece of code which successfully gets the data from the API :
public async Task<string> GetPage(string model)
{
var request =
new HttpRequestMessage(
HttpMethod.Get,
_baseAddress +
model);
var client = _clientFactory.CreateClient();
var response = await client.SendAsync(request);
return await response.Content.ReadAsStringAsync();
}
If I use it, let's say to get the informations from api/something as following : var smth = await GetPage("something") or any other AllowAnonymous method, it will properly works.
But if I want to make it working with an Authorize method, I actually add this piece of code just before sending the request :
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + token);
Where the token variable contains my JWT hardwritten in code for testing purpose. Everything works fine too.
So now I'm obviously trying to avoid hardwritting the JWT. I decided to store it on the client side in an HttpOnly Cookie coupled with the AntiForgeryToken native function from ASP.NET Core. I wrote this code to store the cookie :
private void Authenticate(string token)
{
Response.Cookies.Append(
"JWT",
token,
new CookieOptions()
{
HttpOnly = true,
Secure = true,
}
);
}
And now I'm stucked here. Because I use it as a Service, my ClientService is the same for all my users. So I can't store the token somewhere and pass it to the newly created client for each request.
I tried to add the JWT to the header before calling the ClientService as following :
public async Task<ActionResult> Index()
{
Request.Headers.Add("Authorization", "Bearer " + Request.Cookies["JWT"]);
var users = await ClientService.GetUsersAsync();
//GetUsersAsync() simply call GetPage("users") method and deserialize the JSON returned as a List<User>
return View(users);
}
But because my ClientService create its own client which sends its own request each time I ask for some data from the API with this code :
var request =
new HttpRequestMessage(
HttpMethod.Get,,
_baseAddress +
model);
var client = _clientFactory.CreateClient();
The headers I added before aren't passed to the API.
A simple solution could be to rewrite all my ClientService methods to accept a Token parameter but it seems redundant and painful.
Which is the best and simpliest solution to pass the token to my API ?

The case you are describing is actually Cookie Authentication :
1. Sign in
ClaimsIdentity claimsIdentity = new ClaimsIdentity(CookieAuthenticationDefaults.AuthenticationScheme);
//Not mandatory: you can add the token to claim for future usage, like API request from server to server
claimsIdentity.AddClaim(new Claim("token", tokenId));
var claimsPrincipal = new ClaimsPrincipal(claimsIdentity);
await httpContext.SignInAsync(CookieAuthenticationDefaults.AuthenticationScheme, claimsPrincipal);
2. Add Cookie authentication
services.AddAuthentication(x =>
{
x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(x =>
{
x.RequireHttpsMetadata = true;
x.SaveToken = true;
x.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuerSigningKey = true,
IssuerSigningKey = new SymmetricSecurityKey(key),
ValidateIssuer = false,
ValidateAudience = false,
ValidateLifetime = true,
ClockSkew = TimeSpan.FromMinutes(5),
};
}).AddCookieAuthentication();
AddCookieAuthentication looks like:
public static AuthenticationBuilder AddCookieAuthentication(this IServiceCollection services)
{
var authBuilder = services.AddAuthentication(sharedOptions =>
{
sharedOptions.RequireAuthenticatedSignIn = false;
sharedOptions.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
sharedOptions.DefaultAuthenticateScheme = CookieAuthenticationDefaults.AuthenticationScheme;
})
.AddCookie(CookieAuthenticationDefaults.AuthenticationScheme, opts =>
{
opts.CookieManager = new ChunkingCookieManager();
opts.Cookie = new CookieBuilder()
{
Domain = "CookieDomain",
Name = "CookieName",
Path = "CookiePath",
SecurePolicy = CookieSecurePolicy.Always,
HttpOnly = true,
SameSite = SameSiteMode.Lax,
};
opts.ExpireTimeSpan = TimeSpan.FromMinutes(20);
opts.ForwardDefaultSelector = ctx =>
{
var authHeader = ctx.Request.Headers["Authorization"].FirstOrDefault();
if (authHeader?.StartsWith(JwtBearerDefaults.AuthenticationScheme) == true)
{
return JwtBearerDefaults.AuthenticationScheme;
}
else
{
return CookieAuthenticationDefaults.AuthenticationScheme;
}
};
});
return authBuilder;
}
A browser through which the user signed-in will receive the cookie cookie created in SignIn method and will be able to populate request via client as well.

Ok I figured it out myself, here is how I solved the problem :
1) On Startup.cs, add an HttpContextAccessor :
The Context from our ASP.NET Core website is only accessible by the controllers. The Class libraries can't access it.
To make it available to a class library, we need to use an HttPContextAccessor. It's a service we can use as a dependancy injection to our class library. We just have to add
services.AddHttpContextAccessor();
In the ConfigureServices method from the Startup.cs.
2) Adapt the Class Library
The ClientService needs to be able to receive the Dependancy Injection as following :
public class ClientService : IClientService
{
private readonly IHttpClientFactory _clientFactory;
private readonly IHttpContextAccessor _contextAccessor;
private readonly string _baseAddress = $#"https://localhost:[PORT]/api/";
public ClientService(IHttpClientFactory clientFactory, IHttpContextAccessor contextAccessor)
{
_clientFactory = clientFactory;
_contextAccessor = contextAccessor;
}
}
Now we can access the current context from the HttpContextAccessor _contextAccessor variable.
Next we have to modify our GetPage(string model) method :
public async Task<string> GetPage(string model)
{
var request =
new HttpRequestMessage(
HttpMethod.Get,
_baseAddress +
model);
var client = _clientFactory.CreateClient();
var authorization = _contextAccessor.HttpContext.Request.Headers.FirstOrDefault(x => x.Key == "Authorization").Value.FirstOrDefault();
if(authorization != null)
{
client.DefaultRequestHeaders.Add("Authorization", authorization);
}
var response = await client.SendAsync(request);
return await response.Content.ReadAsStringAsync();
}
The code added will try to get the "Authorization" header from the request and if it's not null, we add it to our own request. This allows the request to the API with the JWT.
3) Add a middleware to add the JWT to each request
Now the final step is to add the JWT to each request from our ASP.NET Core application. If needed, the JWT will be consumed by our Class Library without changing any piece of code, either from the library or from the application.
In order to realise that, we have to add a middleware to the Startup.cs > Configure() method.
The middleware looks like that :
// Add header:
app.Use((context, next) =>
{
var jwt = context.Request.Cookies["JWT"];
if(jwt != null)
{
context.Request.Headers.Add("Authorization", "Bearer " + jwt);
}
return next.Invoke();
});
This just reads the Cookie from the request headers and if the JWT HttpOnly Cookie isn't null, we add the token to our request. This request will then be captured by our Class Library in order to use it to talk with the API.
A few things to note :
Adding the JWT to each request even if we don't need it could consume more bandwidth overtime. It could be also less safe (I'm not a security expert)
Adding the JWT to our main request, then create a local client with its own request in our class library seems not optimal. But it works as expected and I'm actually unaware of how to optimize it.
Feel free to point any issue in my solution or modify it to add some clarifications or even other more efficient ways to achieve it.

Related

C# generate JWT token, where verify signature should be placed [duplicate]

I'm trying to support JWT bearer token (JSON Web Token) in my web API application and I'm getting lost.
I see support for .NET Core and for OWIN applications.
I'm currently hosting my application in IIS.
How can I achieve this authentication module in my application? Is there any way I can use the <authentication> configuration similar to the way I use forms/Windows authentication?
I answered this question: How to secure an ASP.NET Web API 4 years ago using HMAC.
Now, lots of things changed in security, especially that JWT is getting popular. In this answer, I will try to explain how to use JWT in the simplest and basic way that I can, so we won't get lost from jungle of OWIN, Oauth2, ASP.NET Identity, etc..
If you don't know about JWT tokens, you need to take a look at:
https://www.rfc-editor.org/rfc/rfc7519
Basically, a JWT token looks like this:
<base64-encoded header>.<base64-encoded claims>.<base64-encoded signature>
Example:
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1bmlxdWVfbmFtZSI6ImN1b25nIiwibmJmIjoxNDc3NTY1NzI0LCJleHAiOjE0Nzc1NjY5MjQsImlhdCI6MTQ3NzU2NTcyNH0.6MzD1VwA5AcOcajkFyKhLYybr3h13iZjDyHm9zysDFQ
A JWT token has three sections:
Header: JSON format which is encoded in Base64
Claims: JSON format which is encoded in Base64.
Signature: Created and signed based on Header and Claims which is encoded in Base64.
If you use the website jwt.io with the token above, you can decode the token and see it like below:
Technically, JWT uses a signature which is signed from headers and claims with security algorithm specified in the headers (example: HMACSHA256). Therefore, JWT must be transferred over HTTPs if you store any sensitive information in its claims.
Now, in order to use JWT authentication, you don't really need an OWIN middleware if you have a legacy Web Api system. The simple concept is how to provide JWT token and how to validate the token when the request comes. That's it.
In the demo I've created (github), to keep the JWT token lightweight, I only store username and expiration time. But this way, you have to re-build new local identity (principal) to add more information like roles, if you want to do role authorization, etc. But, if you want to add more information into JWT, it's up to you: it's very flexible.
Instead of using OWIN middleware, you can simply provide a JWT token endpoint by using a controller action:
public class TokenController : ApiController
{
// This is naive endpoint for demo, it should use Basic authentication
// to provide token or POST request
[AllowAnonymous]
public string Get(string username, string password)
{
if (CheckUser(username, password))
{
return JwtManager.GenerateToken(username);
}
throw new HttpResponseException(HttpStatusCode.Unauthorized);
}
public bool CheckUser(string username, string password)
{
// should check in the database
return true;
}
}
This is a naive action; in production you should use a POST request or a Basic Authentication endpoint to provide the JWT token.
How to generate the token based on username?
You can use the NuGet package called System.IdentityModel.Tokens.Jwt from Microsoft to generate the token, or even another package if you like. In the demo, I use HMACSHA256 with SymmetricKey:
/// <summary>
/// Use the below code to generate symmetric Secret Key
/// var hmac = new HMACSHA256();
/// var key = Convert.ToBase64String(hmac.Key);
/// </summary>
private const string Secret = "db3OIsj+BXE9NZDy0t8W3TcNekrF+2d/1sFnWG4HnV8TZY30iTOdtVWJG8abWvB1GlOgJuQZdcF2Luqm/hccMw==";
public static string GenerateToken(string username, int expireMinutes = 20)
{
var symmetricKey = Convert.FromBase64String(Secret);
var tokenHandler = new JwtSecurityTokenHandler();
var now = DateTime.UtcNow;
var tokenDescriptor = new SecurityTokenDescriptor
{
Subject = new ClaimsIdentity(new[]
{
new Claim(ClaimTypes.Name, username)
}),
Expires = now.AddMinutes(Convert.ToInt32(expireMinutes)),
SigningCredentials = new SigningCredentials(
new SymmetricSecurityKey(symmetricKey),
SecurityAlgorithms.HmacSha256Signature)
};
var stoken = tokenHandler.CreateToken(tokenDescriptor);
var token = tokenHandler.WriteToken(stoken);
return token;
}
The endpoint to provide the JWT token is done.
How to validate the JWT when the request comes?
In the demo, I have built
JwtAuthenticationAttribute which inherits from IAuthenticationFilter (more detail about authentication filter in here).
With this attribute, you can authenticate any action: you just have to put this attribute on that action.
public class ValueController : ApiController
{
[JwtAuthentication]
public string Get()
{
return "value";
}
}
You can also use OWIN middleware or DelegateHander if you want to validate all incoming requests for your WebAPI (not specific to Controller or action)
Below is the core method from authentication filter:
private static bool ValidateToken(string token, out string username)
{
username = null;
var simplePrinciple = JwtManager.GetPrincipal(token);
var identity = simplePrinciple.Identity as ClaimsIdentity;
if (identity == null || !identity.IsAuthenticated)
return false;
var usernameClaim = identity.FindFirst(ClaimTypes.Name);
username = usernameClaim?.Value;
if (string.IsNullOrEmpty(username))
return false;
// More validate to check whether username exists in system
return true;
}
protected Task<IPrincipal> AuthenticateJwtToken(string token)
{
string username;
if (ValidateToken(token, out username))
{
// based on username to get more information from database
// in order to build local identity
var claims = new List<Claim>
{
new Claim(ClaimTypes.Name, username)
// Add more claims if needed: Roles, ...
};
var identity = new ClaimsIdentity(claims, "Jwt");
IPrincipal user = new ClaimsPrincipal(identity);
return Task.FromResult(user);
}
return Task.FromResult<IPrincipal>(null);
}
The workflow is to use the JWT library (NuGet package above) to validate the JWT token and then return back ClaimsPrincipal. You can perform more validation, like check whether user exists on your system, and add other custom validations if you want.
The code to validate JWT token and get principal back:
public static ClaimsPrincipal GetPrincipal(string token)
{
try
{
var tokenHandler = new JwtSecurityTokenHandler();
var jwtToken = tokenHandler.ReadToken(token) as JwtSecurityToken;
if (jwtToken == null)
return null;
var symmetricKey = Convert.FromBase64String(Secret);
var validationParameters = new TokenValidationParameters()
{
RequireExpirationTime = true,
ValidateIssuer = false,
ValidateAudience = false,
IssuerSigningKey = new SymmetricSecurityKey(symmetricKey)
};
SecurityToken securityToken;
var principal = tokenHandler.ValidateToken(token, validationParameters, out securityToken);
return principal;
}
catch (Exception)
{
//should write log
return null;
}
}
If the JWT token is validated and the principal is returned, you should build a new local identity and put more information into it to check role authorization.
Remember to add config.Filters.Add(new AuthorizeAttribute()); (default authorization) at global scope in order to prevent any anonymous request to your resources.
You can use Postman to test the demo:
Request token (naive as I mentioned above, just for demo):
GET http://localhost:{port}/api/token?username=cuong&password=1
Put JWT token in the header for authorized request, example:
GET http://localhost:{port}/api/value
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1bmlxdWVfbmFtZSI6ImN1b25nIiwibmJmIjoxNDc3NTY1MjU4LCJleHAiOjE0Nzc1NjY0NTgsImlhdCI6MTQ3NzU2NTI1OH0.dSwwufd4-gztkLpttZsZ1255oEzpWCJkayR_4yvNL1s
The demo can be found here: https://github.com/cuongle/WebApi.Jwt
I've managed to achieve it with minimal effort (just as simple as with ASP.NET Core).
For that I use OWIN Startup.cs file and Microsoft.Owin.Security.Jwt library.
In order for the app to hit Startup.cs we need to amend Web.config:
<configuration>
<appSettings>
<add key="owin:AutomaticAppStartup" value="true" />
...
Here's how Startup.cs should look:
using MyApp.Helpers;
using Microsoft.IdentityModel.Tokens;
using Microsoft.Owin;
using Microsoft.Owin.Security;
using Microsoft.Owin.Security.Jwt;
using Owin;
[assembly: OwinStartup(typeof(MyApp.App_Start.Startup))]
namespace MyApp.App_Start
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
app.UseJwtBearerAuthentication(
new JwtBearerAuthenticationOptions
{
AuthenticationMode = AuthenticationMode.Active,
TokenValidationParameters = new TokenValidationParameters()
{
ValidAudience = ConfigHelper.GetAudience(),
ValidIssuer = ConfigHelper.GetIssuer(),
IssuerSigningKey = ConfigHelper.GetSymmetricSecurityKey(),
ValidateLifetime = true,
ValidateIssuerSigningKey = true
}
});
}
}
}
Many of you guys use ASP.NET Core nowadays, so as you can see it doesn't differ a lot from what we have there.
It really got me perplexed first, I was trying to implement custom providers, etc. But I didn't expect it to be so simple. OWIN just rocks!
Just one thing to mention - after I enabled OWIN Startup NSWag library stopped working for me (e.g. some of you might want to auto-generate typescript HTTP proxies for Angular app).
The solution was also very simple - I replaced NSWag with Swashbuckle and didn't have any further issues.
Ok, now sharing ConfigHelper code:
public class ConfigHelper
{
public static string GetIssuer()
{
string result = System.Configuration.ConfigurationManager.AppSettings["Issuer"];
return result;
}
public static string GetAudience()
{
string result = System.Configuration.ConfigurationManager.AppSettings["Audience"];
return result;
}
public static SigningCredentials GetSigningCredentials()
{
var result = new SigningCredentials(GetSymmetricSecurityKey(), SecurityAlgorithms.HmacSha256);
return result;
}
public static string GetSecurityKey()
{
string result = System.Configuration.ConfigurationManager.AppSettings["SecurityKey"];
return result;
}
public static byte[] GetSymmetricSecurityKeyAsBytes()
{
var issuerSigningKey = GetSecurityKey();
byte[] data = Encoding.UTF8.GetBytes(issuerSigningKey);
return data;
}
public static SymmetricSecurityKey GetSymmetricSecurityKey()
{
byte[] data = GetSymmetricSecurityKeyAsBytes();
var result = new SymmetricSecurityKey(data);
return result;
}
public static string GetCorsOrigins()
{
string result = System.Configuration.ConfigurationManager.AppSettings["CorsOrigins"];
return result;
}
}
Another important aspect - I sent JWT Token via Authorization header, so typescript code looks for me as follows:
(the code below is generated by NSWag)
#Injectable()
export class TeamsServiceProxy {
private http: HttpClient;
private baseUrl: string;
protected jsonParseReviver: ((key: string, value: any) => any) | undefined = undefined;
constructor(#Inject(HttpClient) http: HttpClient, #Optional() #Inject(API_BASE_URL) baseUrl?: string) {
this.http = http;
this.baseUrl = baseUrl ? baseUrl : "https://localhost:44384";
}
add(input: TeamDto | null): Observable<boolean> {
let url_ = this.baseUrl + "/api/Teams/Add";
url_ = url_.replace(/[?&]$/, "");
const content_ = JSON.stringify(input);
let options_ : any = {
body: content_,
observe: "response",
responseType: "blob",
headers: new HttpHeaders({
"Content-Type": "application/json",
"Accept": "application/json",
"Authorization": "Bearer " + localStorage.getItem('token')
})
};
See headers part - "Authorization": "Bearer " + localStorage.getItem('token')
Here's a very minimal and secure implementation of a Claims based Authentication using JWT token in an ASP.NET Core Web API.
first of all, you need to expose an endpoint that returns a JWT token with claims assigned to a user:
/// <summary>
/// Login provides API to verify user and returns authentication token.
/// API Path: api/account/login
/// </summary>
/// <param name="paramUser">Username and Password</param>
/// <returns>{Token: [Token] }</returns>
[HttpPost("login")]
[AllowAnonymous]
public async Task<IActionResult> Login([FromBody] UserRequestVM paramUser, CancellationToken ct)
{
var result = await UserApplication.PasswordSignInAsync(paramUser.Email, paramUser.Password, false, lockoutOnFailure: false);
if (result.Succeeded)
{
UserRequestVM request = new UserRequestVM();
request.Email = paramUser.Email;
ApplicationUser UserDetails = await this.GetUserByEmail(request);
List<ApplicationClaim> UserClaims = await this.ClaimApplication.GetListByUser(UserDetails);
var Claims = new ClaimsIdentity(new Claim[]
{
new Claim(JwtRegisteredClaimNames.Sub, paramUser.Email.ToString()),
new Claim(UserId, UserDetails.UserId.ToString())
});
//Adding UserClaims to JWT claims
foreach (var item in UserClaims)
{
Claims.AddClaim(new Claim(item.ClaimCode, string.Empty));
}
var tokenHandler = new JwtSecurityTokenHandler();
// this information will be retrived from you Configuration
//I have injected Configuration provider service into my controller
var encryptionkey = Configuration["Jwt:Encryptionkey"];
var key = Encoding.ASCII.GetBytes(encryptionkey);
var tokenDescriptor = new SecurityTokenDescriptor
{
Issuer = Configuration["Jwt:Issuer"],
Subject = Claims,
// this information will be retrived from you Configuration
//I have injected Configuration provider service into my controller
Expires = DateTime.UtcNow.AddMinutes(Convert.ToDouble(Configuration["Jwt:ExpiryTimeInMinutes"])),
//algorithm to sign the token
SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature)
};
var token = tokenHandler.CreateToken(tokenDescriptor);
var tokenString = tokenHandler.WriteToken(token);
return Ok(new
{
token = tokenString
});
}
return BadRequest("Wrong Username or password");
}
now you need to Add Authentication to your services in your ConfigureServices inside your startup.cs to add JWT authentication as your default authentication service like this:
services.AddAuthentication(x =>
{
x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(cfg =>
{
cfg.RequireHttpsMetadata = false;
cfg.SaveToken = true;
cfg.TokenValidationParameters = new TokenValidationParameters()
{
//ValidateIssuerSigningKey = true,
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(configuration["JWT:Encryptionkey"])),
ValidateAudience = false,
ValidateLifetime = true,
ValidIssuer = configuration["Jwt:Issuer"],
//ValidAudience = Configuration["Jwt:Audience"],
//IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["JWT:Key"])),
};
});
now you can add policies to your authorization services like this:
services.AddAuthorization(options =>
{
options.AddPolicy("YourPolicyNameHere",
policy => policy.RequireClaim("YourClaimNameHere"));
});
ALTERNATIVELY, You can also (not necessary) populate all of your claims from your database as this will only run once on your application startup and add them to policies like this:
services.AddAuthorization(async options =>
{
var ClaimList = await claimApplication.GetList(applicationClaim);
foreach (var item in ClaimList)
{
options.AddPolicy(item.ClaimCode, policy => policy.RequireClaim(item.ClaimCode));
}
});
now you can put the Policy filter on any of the methods that you want to be authorized like this:
[HttpPost("update")]
[Authorize(Policy = "ACC_UP")]
public async Task<IActionResult> Update([FromBody] UserRequestVM requestVm, CancellationToken ct)
{
//your logic goes here
}
Hope this helps
In my case the JWT is created by a separate API so ASP.NET need only decode and validate it. In contrast to the accepted answer we're using RSA which is a non-symmetric algorithm, so the SymmetricSecurityKey class mentioned above won't work.
Here's the result.
using Microsoft.IdentityModel.Protocols;
using Microsoft.IdentityModel.Protocols.OpenIdConnect;
using Microsoft.IdentityModel.Tokens;
using System;
using System.IdentityModel.Tokens.Jwt;
using System.Threading;
using System.Threading.Tasks;
public static async Task<JwtSecurityToken> VerifyAndDecodeJwt(string accessToken)
{
try
{
var configurationManager = new ConfigurationManager<OpenIdConnectConfiguration>($"{securityApiOrigin}/.well-known/openid-configuration", new OpenIdConnectConfigurationRetriever());
var openIdConfig = await configurationManager.GetConfigurationAsync(CancellationToken.None);
var validationParameters = new TokenValidationParameters()
{
ValidateLifetime = true,
ValidateAudience = false,
ValidateIssuer = false,
RequireSignedTokens = true,
IssuerSigningKeys = openIdConfig.SigningKeys,
};
new JwtSecurityTokenHandler().ValidateToken(accessToken, validationParameters, out var validToken);
// threw on invalid, so...
return validToken as JwtSecurityToken;
}
catch (Exception ex)
{
logger.Info(ex.Message);
return null;
}
}
I think you should use some 3d party server to support the JWT token and there is no out of the box JWT support in WEB API 2.
However there is an OWIN project for supporting some format of signed token (not JWT). It works as a reduced OAuth protocol to provide just a simple form of authentication for a web site.
You can read more about it e.g. here.
It's rather long, but most parts are details with controllers and ASP.NET Identity that you might not need at all. Most important are
Step 9: Add support for OAuth Bearer Tokens Generation
Step 12: Testing the Back-end API
There you can read how to set up endpoint (e.g. "/token") that you can access from frontend (and details on the format of the request).
Other steps provide details on how to connect that endpoint to the database, etc. and you can chose the parts that you require.
You no need to work with weird JwtSecurityTokenHandler API
Use JwtUtils Nuget package with simple API
var claims = new Dictionary<string, object>
{
{ "exp", 1639942616 },
{ "uname", "i.a.ivanov" },
{ "claim1", "claim1_value" },
{ "claims_array", new [] {"claim_item1", "claim_item2"}}
};
string token = JWT.HS256.Create(claims, "{TOKEN_SECRET}");
You can follow this code for token controller or for more details you can visit here : How to Secure API using JWT Tokens. Building CRUD API using JWT Tokens with ASP.NET Core and Entity Framework Core and Swagger
From here you can learn to use JWT Token in a very easy way
using JWTToken.Models;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.IdentityModel.Tokens;
using System;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
using System.Threading.Tasks;
namespace JWTToken.Controllers
{
[Route("api/[controller]")]
[ApiController]
public class TokenController : ControllerBase
{
public IConfiguration _configuration;
private readonly InventoryContext _context;
public TokenController(IConfiguration config, InventoryContext context)
{
_configuration = config;
_context = context;
}
[HttpPost]
public async Task<IActionResult> Post(UserInfo _userData)
{
if (_userData != null && _userData.Email != null && _userData.Password != null)
{
var user = await GetUser(_userData.Email, _userData.Password);
if (user != null)
{
//create claims details based on the user information
var claims = new[] {
new Claim(JwtRegisteredClaimNames.Sub, _configuration["Jwt:Subject"]),
new Claim(JwtRegisteredClaimNames.Jti, Guid.NewGuid().ToString()),
new Claim(JwtRegisteredClaimNames.Iat, DateTime.UtcNow.ToString()),
new Claim("Id", user.UserId.ToString()),
new Claim("FirstName", user.FirstName),
new Claim("LastName", user.LastName),
new Claim("UserName", user.UserName),
new Claim("Email", user.Email)
};
var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_configuration["Jwt:Key"]));
var signIn = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
var token = new JwtSecurityToken(_configuration["Jwt:Issuer"], _configuration["Jwt:Audience"], claims, expires: DateTime.UtcNow.AddDays(1), signingCredentials: signIn);
return Ok(new JwtSecurityTokenHandler().WriteToken(token));
}
else
{
return BadRequest("Invalid credentials");
}
}
else
{
return BadRequest();
}
}
private async Task<UserInfo> GetUser(string email, string password)
{
return await _context.UserInfos.FirstOrDefaultAsync(u => u.Email == email && u.Password == password);
}
}
}

Blazor WebAssembly 401 Unauthorized even when I am authorized

I am using Blazor WebAssembly Asp.Net Core hosted PWAand integrated the AspNetCore.Identity into it. I created the AuthenticationStateProvider in the Client-Side and now I want to allow the user access to a controller where he needs to be authorized.
I have tested via postman, the users were been created and stored in DB as aspnetusers with the right credentials. The Login/Account Controller work as I wanted it.
When the user is authorized it tells this exception in the browser when accessing the authorized controller request:
Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
Unhandled exception rendering component: Response status code does not indicate success: 401 (Unauthorized).
System.Net.Http.HttpRequestException: Response status code does not
indicate success: 401 (Unauthorized).
Startup.cs (ConfigureServices-Method):
...
serviceCollection.AddDbContext<SQLiteTestDbContext>(options =>
{
options.UseSqlite(config["ConnectionStrings:SQLiteTestConnection"]);
});
serviceCollection.AddDefaultIdentity<IdentityUser>()
.AddEntityFrameworkStores<SQLiteTestDbContext>()
.AddDefaultTokenProviders();
services.AddAuthentication(x =>
{
x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(options =>
{
options.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuer = true,
ValidateAudience = true,
ValidateLifetime = true,
ValidateIssuerSigningKey = true,
ValidIssuer = Configuration["JwtIssuer"],
ValidAudience = Configuration["JwtAudience"],
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["JwtSecurityKey"]))
};
});
services.AddHttpContextAccessor();
services.Configure<IdentityOptions>(options =>
options.ClaimsIdentity.UserIdClaimType = ClaimTypes.NameIdentifier);
...
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
...
app.UseAuthentication();
app.UseAuthorization();
...
}
Program.cs Client-Side
public static async Task Main(string[] args)
{
var builder = WebAssemblyHostBuilder.CreateDefault(args);
builder.RootComponents.Add<App>("app");
builder.Logging.SetMinimumLevel(LogLevel.Warning);
//Registering Shared-Library models
builder.Services.AddScoped<ObjectModel>();
builder.Services.AddBlazoredLocalStorage();
builder.Services.AddAuthorizationCore();
builder.Services.AddScoped<AuthenticationStateProvider, ApiAuthenticationStateProvider>();
builder.Services.AddScoped<IAuthService, AuthService>();
//Registered BlazorContextMenu Service
builder.Services.AddBlazorContextMenu();
//Registering FileReader service, for image upload -> Azure
builder.Services.AddFileReaderService(options => options.UseWasmSharedBuffer = true);
builder.Services.AddTransient(sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });
await builder.Build().RunAsync();
}
My Controller with authorize attribute:
[Authorize(AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]
[Route("api/[controller]")]
[ApiController]
public class ObjectController : ControllerBase
{
....
Note:
When your user tries to access a protected (annotated with the Authorize attribute) page on the client he should login first or register.
In order to register, he should be redirected to an Account Controller where you should create a new user, and add it to the database (You said you " integrated the AspNetCore.Identity into it"), which is fine...and should be used to authenticate and verify the user's identity. You account controller should also produce a Jwt Token that should be passed to the client app, and stored in the local storage.
Now, whenever your user tries to access protected resources on your Web Api endpoints, you should retrieve the Jwt Token from the local storage, and add it to the request header. If you do so, the Unauthorized response would be something of the past.
Custom AuthenticationStateProvider can be a good place from which you can manage storing the Jwt Token in the local storage and retrieving it for outbound HTTP request calls.
Here's some sample code to clarify what you should do:
#code {
WeatherForecast[] forecasts;
protected override async Task OnInitializedAsync()
{
var token = await TokenProvider.GetTokenAsync();
forecasts = await Http.GetJsonAsync<WeatherForecast[]>(
"api/WeatherForecast",
new AuthenticationHeaderValue("Bearer", token));
}
}
Note: TokenProvider is a custom AuthenticationStateProvider that defines a method called GetTokenAsync that provides (reading the Jwt Token from the local storage and passing it to the calling code) the Jwt Token
Hope this helps...
In case of Linux App Service in combination with ID Server the Authority needs to be set according to Microsoft documentation: https://learn.microsoft.com/en-us/aspnet/core/security/authentication/identity-api-authorization?view=aspnetcore-5.0#azure-app-service-on-linux-1
services.Configure<JwtBearerOptions>(
IdentityServerJwtConstants.IdentityServerJwtBearerScheme,
options =>
{
options.Authority = "{AUTHORITY}";
});
Example: options.Authority = "https://contoso-service.azurewebsites.net";

ASP.NET Core WebAPI Cookie + JWT Authentication

we have a SPA (Angular) with API backend (ASP.NET Core WebAPI):
SPA is listens on app.mydomain.com, API on app.mydomain.com/API
We use JWT for Authentication with built-in Microsoft.AspNetCore.Authentication.JwtBearer; I have a controller app.mydomain.com/API/auth/jwt/login which creates tokens. SPA saves them into local storage. All works perfect. After a security audit, we have been told to switch local storage for cookies.
The problem is, that API on app.mydomain.com/API is used by SPA but also by a mobile app and several customers server-2-server solutions.
So, we have to keep JWT as is, but add Cookies. I found several articles which combines Cookies and JWT on different controllers, but I need them work side-by-side on each controller.
If client sends cookies, authenticate via cookies. If client sends JWT bearer, authenticate via JWT.
Is this achievable via built-in ASP.NET authentication or DIY middleware?
Thanks!
Okay, I have been trying achieving this for a while and i solved same issue of using jwt Authentication Tokens and Cookie Authentication with the following code.
API Service Provider UserController.cs
This Provide Different Services to the User with Both (Cookie and JWT Bearer)Authentication Schemes
[Authorize(AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]
[Authorize(AuthenticationSchemes = CookieAuthenticationDefaults.AuthenticationScheme)]
[Route("[controller]")]
[ApiController]
public class UsersController : ControllerBase
{
private readonly IUserServices_Api _services;
public UsersController(IUserServices_Api services)
{
this._services = services;
}
[HttpGet]
public IEnumerable<User> Getall()
{
return _services.GetAll();
}
}
My Startup.cs
public void ConfigureServices(IServiceCollection services)
{
services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
services.AddAuthentication(options => {
options.DefaultSignInScheme = CookieAuthenticationDefaults.AuthenticationScheme;
options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
options.DefaultScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddCookie(options =>
{
options.LoginPath = "/Account/Login";
options.AccessDeniedPath = "/Home/Error";
})
.AddJwtBearer(options =>
{
options.SaveToken = true;
options.RequireHttpsMetadata = false;
options.TokenValidationParameters = new Microsoft.IdentityModel.Tokens.TokenValidationParameters()
{
ValidateIssuer = true,
ValidateAudience = true,
ValidAudience = " you site link blah blah",
ValidIssuer = "You Site link Blah blah",
IssuerSigningKey = new Microsoft.IdentityModel.Tokens.SymmetricSecurityKey(System.Text.Encoding.UTF8.GetBytes(sysController.GetSecurityKey()))
,
ValidateLifetime = true,
ClockSkew = TimeSpan.Zero
};
});
}
And further if you want custom Authentication for a specific Controller
then you have to specify the Authentitcation Type for the Authorization
like:
[Authorize(AuthenticationSchemes = CookieAuthenticationDefaults.AuthenticationScheme)]
public IActionResult Index()
{
return View(); // This can only be Access when Cookie Authentication is Authorized.
}
[Authorize(AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]
public IActionResult Index()
{
return View(); // And this one will be Access when JWT Bearer is Valid
}
I've been having the same issue and i just found what it seems to be the solution in another question here in stackoverflow.
Please take a look at this.
I'll try that solution myself and update this answer with the results.
Edit: It seems it's not possible to achieve double authentication types in a same method but the solution provided in the link i mentioned says:
It's not possible to authorize a method with two Schemes Or-Like, but you can use two public methods, to call a private method
//private method
private IActionResult GetThingPrivate()
{
//your Code here
}
//Jwt-Method
[Authorize(AuthenticationSchemes = $"{JwtBearerDefaults.AuthenticationScheme}")]
[HttpGet("bearer")]
public IActionResult GetByBearer()
{
return GetThingsPrivate();
}
//Cookie-Method
[Authorize(AuthenticationSchemes = $"{CookieAuthenticationDefaults.AuthenticationScheme}")]
[HttpGet("cookie")]
public IActionResult GetByCookie()
{
return GetThingsPrivate();
}
Anyway you should take a look at the link, it sure helped me.
Credit goes to Nikolaus for the answer.
I have not been able to find much information on a good way to do this - having to duplicate the API is a pain just to support 2 authorization schemes.
I have been looking into the idea of using a reverse proxy and it looks to me like a good solution for this.
User signs into Website (use cookie httpOnly for session)
Website uses Anti-Forgery token
SPA sends request to website server and includes anti-forgery token in header: https://app.mydomain.com/api/secureResource
Website server verifies anti-forgery token (CSRF)
Website server determines request is for API and should send it to the reverse proxy
Website server gets users access token for API
Reverse proxy forwards request to API: https://api.mydomain.com/api/secureResource
Note that the anti-forgery token (#2,#4) is critical or else you could expose your API to CSRF attacks.
Example (.NET Core 2.1 MVC with IdentityServer4):
To get a working example of this I started with the IdentityServer4 quick start Switching to Hybrid Flow and adding API Access back. This sets up the scenario I was after where a MVC application uses cookies and can request an access_token from the identity server to make calls the API.
I used Microsoft.AspNetCore.Proxy for the reverse proxy and modified the quick start.
MVC Startup.ConfigureServices:
services.AddAntiforgery();
services.TryAddSingleton<IHttpContextAccessor, HttpContextAccessor>();
MVC Startup.Configure:
app.MapWhen(IsApiRequest, builder =>
{
builder.UseAntiforgeryTokens();
var messageHandler = new BearerTokenRequestHandler(builder.ApplicationServices);
var proxyOptions = new ProxyOptions
{
Scheme = "https",
Host = "api.mydomain.com",
Port = "443",
BackChannelMessageHandler = messageHandler
};
builder.RunProxy(proxyOptions);
});
private static bool IsApiRequest(HttpContext httpContext)
{
return httpContext.Request.Path.Value.StartsWith(#"/api/", StringComparison.OrdinalIgnoreCase);
}
ValidateAntiForgeryToken (Marius Schulz):
public class ValidateAntiForgeryTokenMiddleware
{
private readonly RequestDelegate next;
private readonly IAntiforgery antiforgery;
public ValidateAntiForgeryTokenMiddleware(RequestDelegate next, IAntiforgery antiforgery)
{
this.next = next;
this.antiforgery = antiforgery;
}
public async Task Invoke(HttpContext context)
{
await antiforgery.ValidateRequestAsync(context);
await next(context);
}
}
public static class ApplicationBuilderExtensions
{
public static IApplicationBuilder UseAntiforgeryTokens(this IApplicationBuilder app)
{
return app.UseMiddleware<ValidateAntiForgeryTokenMiddleware>();
}
}
BearerTokenRequestHandler:
public class BearerTokenRequestHandler : DelegatingHandler
{
private readonly IServiceProvider serviceProvider;
public BearerTokenRequestHandler(IServiceProvider serviceProvider, HttpMessageHandler innerHandler = null)
{
this.serviceProvider = serviceProvider;
InnerHandler = innerHandler ?? new HttpClientHandler();
}
protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
var httpContextAccessor = serviceProvider.GetService<IHttpContextAccessor>();
var accessToken = await httpContextAccessor.HttpContext.GetTokenAsync("access_token");
request.Headers.Authorization =new AuthenticationHeaderValue("Bearer", accessToken);
var result = await base.SendAsync(request, cancellationToken);
return result;
}
}
_Layout.cshtml:
#Html.AntiForgeryToken()
Then using your SPA framework you can make a request. To verify I just did a simple AJAX request:
<a onclick="sendSecureAjaxRequest()">Do Secure AJAX Request</a>
<div id="ajax-content"></div>
<script language="javascript">
function sendSecureAjaxRequest(path) {
var myRequest = new XMLHttpRequest();
myRequest.open('GET', '/api/secureResource');
myRequest.setRequestHeader("RequestVerificationToken",
document.getElementsByName('__RequestVerificationToken')[0].value);
myRequest.onreadystatechange = function () {
if (myRequest.readyState === XMLHttpRequest.DONE) {
if (myRequest.status === 200) {
document.getElementById('ajax-content').innerHTML = myRequest.responseText;
} else {
alert('There was an error processing the AJAX request: ' + myRequest.status);
}
}
};
myRequest.send();
};
</script>
This was a proof of concept test so your mileage may very and I'm pretty new to .NET Core and middleware configuration so it could probably look prettier. I did limited testing with this and only did a GET request to the API and did not use SSL (https).
As expected, if the anti-forgery token is removed from the AJAX request it fails. If the user is has not logged in (authenticated) the request fails.
As always, each project is unique so always verify your security requirements are met. Please take a look at any comments left on this answer for any potential security concerns someone might raise.
On another note, I think once subresource integrity (SRI) and content security policy (CSP) is available on all commonly used browsers (i.e. older browsers are phased out) local storage should be re-evaluated to store API tokens which will lesson the complexity of token storage. SRI and CSP should be used now to help reduce the attack surface for supporting browsers.
I think the easiest solution is one proposed by David Kirkland:
Create combined authorization policy (in ConfigureServices(IServiceCollection services)):
services.AddAuthorization(options =>
{
var defaultAuthorizationPolicyBuilder = new AuthorizationPolicyBuilder(
CookieAuthenticationDefaults.AuthenticationScheme,
JwtBearerDefaults.AuthenticationScheme);
defaultAuthorizationPolicyBuilder =
defaultAuthorizationPolicyBuilder.RequireAuthenticatedUser();
options.DefaultPolicy = defaultAuthorizationPolicyBuilder.Build();
});
And add middleware that will redirect to login in case of 401 (in Configure(IApplicationBuilder app)):
app.UseAuthentication();
app.Use(async (context, next) =>
{
await next();
var bearerAuth = context.Request.Headers["Authorization"]
.FirstOrDefault()?.StartsWith("Bearer ") ?? false;
if (context.Response.StatusCode == 401
&& !context.User.Identity.IsAuthenticated
&& !bearerAuth)
{
await context.ChallengeAsync("oidc");
}
});
while looking for combined firebase authorization with net core web api (cookie for web site and authorization header for mobile app ) end with the following solution.
public void ConfigureServices(IServiceCollection services)
{
services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
.AddJwtBearer(options =>
{
options.Authority = "https://securetoken.google.com/xxxxx";
options.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuer = true,
ValidIssuer = options.Authority,
ValidateAudience = true,
ValidAudience = "xxxxx",
ValidateLifetime = true
};
options.Events = new JwtBearerEvents
{
OnMessageReceived = context =>
{
if (context.Request.Cookies.ContainsKey(GlobalConst.JwtBearer))
{
context.Token = context.Request.Cookies[GlobalConst.JwtBearer];
}
else if (context.Request.Headers.ContainsKey("Authorization"))
{
var authhdr = context.Request.Headers["Authorization"].FirstOrDefault(k=>k.StartsWith(GlobalConst.JwtBearer));
if (!string.IsNullOrEmpty(authhdr))
{
var keyval = authhdr.Split(" ");
if (keyval != null && keyval.Length > 1) context.Token = keyval[1];
}
}
return Task.CompletedTask;
}
};
});
where
public static readonly string JwtBearer = "Bearer";
seems working fine.
checked it from mobile & postman (for cookie )
with this code you can use cookie and header in the same time.
if cookie is null then check the header automatically.
add this code in AddJwtBearer options.
options.Events = new JwtBearerEvents
{
OnMessageReceived = context =>
{
context.Token = context.Request.Cookies["Authorization"];
return Task.CompletedTask;
}
};
full usage is:
services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
.AddJwtBearer(JwtBearerDefaults.AuthenticationScheme, options =>
{
options.RequireHttpsMetadata = false;
options.SaveToken = false;
options.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuer = true,
ValidateAudience = true,
ValidAudience = Configuration["JwtToken:Audience"],
ValidIssuer = Configuration["JwtToken:Issuer"],
IssuerSigningKey =
new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["JwtToken:Key"]))
};
options.Events = new JwtBearerEvents
{
OnMessageReceived = context =>
{
context.Token = context.Request.Cookies["Authorization"];
return Task.CompletedTask;
}
};
});
Header => Authorization: Bearer Your-Token
or
Cookie => Authorization=Your-Token
//dont add Bearer in Cookie
I found this nice article by Rick Strahl. It is the best solution that I found so far and I used it in .NET 5
Here is the key code in order to combining JWT token and cookie authentication in .NET applications:
services.AddAuthentication(options =>
{
options.DefaultScheme = "JWT_OR_COOKIE";
options.DefaultChallengeScheme = "JWT_OR_COOKIE";
})
.AddCookie( options =>
{
options.LoginPath = "/login";
options.ExpireTimeSpan = TimeSpan.FromDays(1);
})
.AddJwtBearer( options =>
{
options.TokenValidationParameters = new TokenValidationParameters
{
ValidateIssuer = true,
ValidIssuer = config.JwtToken.Issuer,
ValidateAudience = true,
ValidAudience = config.JwtToken.Audience,
ValidateIssuerSigningKey = true,
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(config.JwtToken.SigningKey))
};
})
.AddPolicyScheme("JWT_OR_COOKIE", "JWT_OR_COOKIE", options =>
{
options.ForwardDefaultSelector = context =>
{
string authorization = context.Request.Headers[HeaderNames.Authorization];
if (!string.IsNullOrEmpty(authorization) && authorization.StartsWith("Bearer "))
return JwtBearerDefaults.AuthenticationScheme;
return CookieAuthenticationDefaults.AuthenticationScheme;
};
});
ASP.NET Core 2.0 Web API
Please follow this post for implementing JWT Token based authentication
https://fullstackmark.com/post/13/jwt-authentication-with-aspnet-core-2-web-api-angular-5-net-core-identity-and-facebook-login
If you are using visual studio make sure apply the Bearer type athentication type with the filter
[Authorize(AuthenticationSchemes = JwtBearerDefaults.AuthenticationScheme)]
for controller or actions.

HttpClient to call Azure AD-protected site

Following some Microsoft samples, I got to this point:
ASP.NET Core setup:
app.UseCookieAuthentication(new CookieAuthenticationOptions());
app.UseOpenIdConnectAuthentication(new OpenIdConnectOptions
{
ClientId = Configuration["Authentication:AzureAD:ClientId"],
Authority = Configuration["Authentication:AzureAd:Authority"],
ResponseType = OpenIdConnectResponseType.IdToken,
AutomaticAuthenticate = true,
TokenValidationParameters = new TokenValidationParameters()
});
AuthorizationTest endpoint:
[HttpGet]
[Authorize]
public IActionResult Get()
{
return Ok("SAMPLE TEXT - if you can read this then call it a day :)");
}
Client:
try
{
var result = await authContext.AcquireTokenAsync(WebApiResourceId, WebApiClientId, WebApiRedirectUri, new PlatformParameters(PromptBehavior.Auto));
authorizedClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", result.AccessToken);
var authorizedMessage = await authorizedClient.GetAsync("/AuthorizationTest");
var statusCode = authorizedMessage.StatusCode.ToString();
var message = await authorizedMessage.Content.ReadAsStringAsync();
webBrowser.NavigateToString(message);
}
And the authorizedClient is initiated as:
private static HttpClientHandler handler = new HttpClientHandler
{
AllowAutoRedirect = true,
CookieContainer = new CookieContainer(),
UseCookies = true
};
private static HttpClient authorizedClient = new HttpClient(handler, false) { BaseAddress = WebApiBaseUri };
I used to initialize it only with the BaseAddress, and later added the handler following an answer here on So.
The problem:
Even though I get the token from AAD correctly, the response from the WEB API endpoint is an HTML (after an auto-redirect) that is the MS login page with the error "Your browser is set to block cookies....."
What should I change to make the HttpClient work? Or can I change the WebApi configuration to not use cookies? For the latter option I couldn't find any other alternative.
As discussed in the comments, you need to use the JWT bearer token middleware from the package Microsoft.AspNetCore.Authentication.JwtBearer.
The Open ID Connect middleware is designed to redirect a user to a sign in page, not for authenticating access tokens. An example usage of the JWT bearer token middleware can be found here: https://github.com/Azure-Samples/active-directory-dotnet-native-aspnetcore/blob/master/TodoListService/Startup.cs.
Take a look at this thread: https://github.com/AzureAD/azure-activedirectory-library-for-dotnet/issues/514 - it is showing the scenario you are trying to achieve.

JWT authentication for ASP.NET Web API

I'm trying to support JWT bearer token (JSON Web Token) in my web API application and I'm getting lost.
I see support for .NET Core and for OWIN applications.
I'm currently hosting my application in IIS.
How can I achieve this authentication module in my application? Is there any way I can use the <authentication> configuration similar to the way I use forms/Windows authentication?
I answered this question: How to secure an ASP.NET Web API 4 years ago using HMAC.
Now, lots of things changed in security, especially that JWT is getting popular. In this answer, I will try to explain how to use JWT in the simplest and basic way that I can, so we won't get lost from jungle of OWIN, Oauth2, ASP.NET Identity, etc..
If you don't know about JWT tokens, you need to take a look at:
https://www.rfc-editor.org/rfc/rfc7519
Basically, a JWT token looks like this:
<base64-encoded header>.<base64-encoded claims>.<base64-encoded signature>
Example:
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1bmlxdWVfbmFtZSI6ImN1b25nIiwibmJmIjoxNDc3NTY1NzI0LCJleHAiOjE0Nzc1NjY5MjQsImlhdCI6MTQ3NzU2NTcyNH0.6MzD1VwA5AcOcajkFyKhLYybr3h13iZjDyHm9zysDFQ
A JWT token has three sections:
Header: JSON format which is encoded in Base64
Claims: JSON format which is encoded in Base64.
Signature: Created and signed based on Header and Claims which is encoded in Base64.
If you use the website jwt.io with the token above, you can decode the token and see it like below:
Technically, JWT uses a signature which is signed from headers and claims with security algorithm specified in the headers (example: HMACSHA256). Therefore, JWT must be transferred over HTTPs if you store any sensitive information in its claims.
Now, in order to use JWT authentication, you don't really need an OWIN middleware if you have a legacy Web Api system. The simple concept is how to provide JWT token and how to validate the token when the request comes. That's it.
In the demo I've created (github), to keep the JWT token lightweight, I only store username and expiration time. But this way, you have to re-build new local identity (principal) to add more information like roles, if you want to do role authorization, etc. But, if you want to add more information into JWT, it's up to you: it's very flexible.
Instead of using OWIN middleware, you can simply provide a JWT token endpoint by using a controller action:
public class TokenController : ApiController
{
// This is naive endpoint for demo, it should use Basic authentication
// to provide token or POST request
[AllowAnonymous]
public string Get(string username, string password)
{
if (CheckUser(username, password))
{
return JwtManager.GenerateToken(username);
}
throw new HttpResponseException(HttpStatusCode.Unauthorized);
}
public bool CheckUser(string username, string password)
{
// should check in the database
return true;
}
}
This is a naive action; in production you should use a POST request or a Basic Authentication endpoint to provide the JWT token.
How to generate the token based on username?
You can use the NuGet package called System.IdentityModel.Tokens.Jwt from Microsoft to generate the token, or even another package if you like. In the demo, I use HMACSHA256 with SymmetricKey:
/// <summary>
/// Use the below code to generate symmetric Secret Key
/// var hmac = new HMACSHA256();
/// var key = Convert.ToBase64String(hmac.Key);
/// </summary>
private const string Secret = "db3OIsj+BXE9NZDy0t8W3TcNekrF+2d/1sFnWG4HnV8TZY30iTOdtVWJG8abWvB1GlOgJuQZdcF2Luqm/hccMw==";
public static string GenerateToken(string username, int expireMinutes = 20)
{
var symmetricKey = Convert.FromBase64String(Secret);
var tokenHandler = new JwtSecurityTokenHandler();
var now = DateTime.UtcNow;
var tokenDescriptor = new SecurityTokenDescriptor
{
Subject = new ClaimsIdentity(new[]
{
new Claim(ClaimTypes.Name, username)
}),
Expires = now.AddMinutes(Convert.ToInt32(expireMinutes)),
SigningCredentials = new SigningCredentials(
new SymmetricSecurityKey(symmetricKey),
SecurityAlgorithms.HmacSha256Signature)
};
var stoken = tokenHandler.CreateToken(tokenDescriptor);
var token = tokenHandler.WriteToken(stoken);
return token;
}
The endpoint to provide the JWT token is done.
How to validate the JWT when the request comes?
In the demo, I have built
JwtAuthenticationAttribute which inherits from IAuthenticationFilter (more detail about authentication filter in here).
With this attribute, you can authenticate any action: you just have to put this attribute on that action.
public class ValueController : ApiController
{
[JwtAuthentication]
public string Get()
{
return "value";
}
}
You can also use OWIN middleware or DelegateHander if you want to validate all incoming requests for your WebAPI (not specific to Controller or action)
Below is the core method from authentication filter:
private static bool ValidateToken(string token, out string username)
{
username = null;
var simplePrinciple = JwtManager.GetPrincipal(token);
var identity = simplePrinciple.Identity as ClaimsIdentity;
if (identity == null || !identity.IsAuthenticated)
return false;
var usernameClaim = identity.FindFirst(ClaimTypes.Name);
username = usernameClaim?.Value;
if (string.IsNullOrEmpty(username))
return false;
// More validate to check whether username exists in system
return true;
}
protected Task<IPrincipal> AuthenticateJwtToken(string token)
{
string username;
if (ValidateToken(token, out username))
{
// based on username to get more information from database
// in order to build local identity
var claims = new List<Claim>
{
new Claim(ClaimTypes.Name, username)
// Add more claims if needed: Roles, ...
};
var identity = new ClaimsIdentity(claims, "Jwt");
IPrincipal user = new ClaimsPrincipal(identity);
return Task.FromResult(user);
}
return Task.FromResult<IPrincipal>(null);
}
The workflow is to use the JWT library (NuGet package above) to validate the JWT token and then return back ClaimsPrincipal. You can perform more validation, like check whether user exists on your system, and add other custom validations if you want.
The code to validate JWT token and get principal back:
public static ClaimsPrincipal GetPrincipal(string token)
{
try
{
var tokenHandler = new JwtSecurityTokenHandler();
var jwtToken = tokenHandler.ReadToken(token) as JwtSecurityToken;
if (jwtToken == null)
return null;
var symmetricKey = Convert.FromBase64String(Secret);
var validationParameters = new TokenValidationParameters()
{
RequireExpirationTime = true,
ValidateIssuer = false,
ValidateAudience = false,
IssuerSigningKey = new SymmetricSecurityKey(symmetricKey)
};
SecurityToken securityToken;
var principal = tokenHandler.ValidateToken(token, validationParameters, out securityToken);
return principal;
}
catch (Exception)
{
//should write log
return null;
}
}
If the JWT token is validated and the principal is returned, you should build a new local identity and put more information into it to check role authorization.
Remember to add config.Filters.Add(new AuthorizeAttribute()); (default authorization) at global scope in order to prevent any anonymous request to your resources.
You can use Postman to test the demo:
Request token (naive as I mentioned above, just for demo):
GET http://localhost:{port}/api/token?username=cuong&password=1
Put JWT token in the header for authorized request, example:
GET http://localhost:{port}/api/value
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1bmlxdWVfbmFtZSI6ImN1b25nIiwibmJmIjoxNDc3NTY1MjU4LCJleHAiOjE0Nzc1NjY0NTgsImlhdCI6MTQ3NzU2NTI1OH0.dSwwufd4-gztkLpttZsZ1255oEzpWCJkayR_4yvNL1s
The demo can be found here: https://github.com/cuongle/WebApi.Jwt
I've managed to achieve it with minimal effort (just as simple as with ASP.NET Core).
For that I use OWIN Startup.cs file and Microsoft.Owin.Security.Jwt library.
In order for the app to hit Startup.cs we need to amend Web.config:
<configuration>
<appSettings>
<add key="owin:AutomaticAppStartup" value="true" />
...
Here's how Startup.cs should look:
using MyApp.Helpers;
using Microsoft.IdentityModel.Tokens;
using Microsoft.Owin;
using Microsoft.Owin.Security;
using Microsoft.Owin.Security.Jwt;
using Owin;
[assembly: OwinStartup(typeof(MyApp.App_Start.Startup))]
namespace MyApp.App_Start
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
app.UseJwtBearerAuthentication(
new JwtBearerAuthenticationOptions
{
AuthenticationMode = AuthenticationMode.Active,
TokenValidationParameters = new TokenValidationParameters()
{
ValidAudience = ConfigHelper.GetAudience(),
ValidIssuer = ConfigHelper.GetIssuer(),
IssuerSigningKey = ConfigHelper.GetSymmetricSecurityKey(),
ValidateLifetime = true,
ValidateIssuerSigningKey = true
}
});
}
}
}
Many of you guys use ASP.NET Core nowadays, so as you can see it doesn't differ a lot from what we have there.
It really got me perplexed first, I was trying to implement custom providers, etc. But I didn't expect it to be so simple. OWIN just rocks!
Just one thing to mention - after I enabled OWIN Startup NSWag library stopped working for me (e.g. some of you might want to auto-generate typescript HTTP proxies for Angular app).
The solution was also very simple - I replaced NSWag with Swashbuckle and didn't have any further issues.
Ok, now sharing ConfigHelper code:
public class ConfigHelper
{
public static string GetIssuer()
{
string result = System.Configuration.ConfigurationManager.AppSettings["Issuer"];
return result;
}
public static string GetAudience()
{
string result = System.Configuration.ConfigurationManager.AppSettings["Audience"];
return result;
}
public static SigningCredentials GetSigningCredentials()
{
var result = new SigningCredentials(GetSymmetricSecurityKey(), SecurityAlgorithms.HmacSha256);
return result;
}
public static string GetSecurityKey()
{
string result = System.Configuration.ConfigurationManager.AppSettings["SecurityKey"];
return result;
}
public static byte[] GetSymmetricSecurityKeyAsBytes()
{
var issuerSigningKey = GetSecurityKey();
byte[] data = Encoding.UTF8.GetBytes(issuerSigningKey);
return data;
}
public static SymmetricSecurityKey GetSymmetricSecurityKey()
{
byte[] data = GetSymmetricSecurityKeyAsBytes();
var result = new SymmetricSecurityKey(data);
return result;
}
public static string GetCorsOrigins()
{
string result = System.Configuration.ConfigurationManager.AppSettings["CorsOrigins"];
return result;
}
}
Another important aspect - I sent JWT Token via Authorization header, so typescript code looks for me as follows:
(the code below is generated by NSWag)
#Injectable()
export class TeamsServiceProxy {
private http: HttpClient;
private baseUrl: string;
protected jsonParseReviver: ((key: string, value: any) => any) | undefined = undefined;
constructor(#Inject(HttpClient) http: HttpClient, #Optional() #Inject(API_BASE_URL) baseUrl?: string) {
this.http = http;
this.baseUrl = baseUrl ? baseUrl : "https://localhost:44384";
}
add(input: TeamDto | null): Observable<boolean> {
let url_ = this.baseUrl + "/api/Teams/Add";
url_ = url_.replace(/[?&]$/, "");
const content_ = JSON.stringify(input);
let options_ : any = {
body: content_,
observe: "response",
responseType: "blob",
headers: new HttpHeaders({
"Content-Type": "application/json",
"Accept": "application/json",
"Authorization": "Bearer " + localStorage.getItem('token')
})
};
See headers part - "Authorization": "Bearer " + localStorage.getItem('token')
Here's a very minimal and secure implementation of a Claims based Authentication using JWT token in an ASP.NET Core Web API.
first of all, you need to expose an endpoint that returns a JWT token with claims assigned to a user:
/// <summary>
/// Login provides API to verify user and returns authentication token.
/// API Path: api/account/login
/// </summary>
/// <param name="paramUser">Username and Password</param>
/// <returns>{Token: [Token] }</returns>
[HttpPost("login")]
[AllowAnonymous]
public async Task<IActionResult> Login([FromBody] UserRequestVM paramUser, CancellationToken ct)
{
var result = await UserApplication.PasswordSignInAsync(paramUser.Email, paramUser.Password, false, lockoutOnFailure: false);
if (result.Succeeded)
{
UserRequestVM request = new UserRequestVM();
request.Email = paramUser.Email;
ApplicationUser UserDetails = await this.GetUserByEmail(request);
List<ApplicationClaim> UserClaims = await this.ClaimApplication.GetListByUser(UserDetails);
var Claims = new ClaimsIdentity(new Claim[]
{
new Claim(JwtRegisteredClaimNames.Sub, paramUser.Email.ToString()),
new Claim(UserId, UserDetails.UserId.ToString())
});
//Adding UserClaims to JWT claims
foreach (var item in UserClaims)
{
Claims.AddClaim(new Claim(item.ClaimCode, string.Empty));
}
var tokenHandler = new JwtSecurityTokenHandler();
// this information will be retrived from you Configuration
//I have injected Configuration provider service into my controller
var encryptionkey = Configuration["Jwt:Encryptionkey"];
var key = Encoding.ASCII.GetBytes(encryptionkey);
var tokenDescriptor = new SecurityTokenDescriptor
{
Issuer = Configuration["Jwt:Issuer"],
Subject = Claims,
// this information will be retrived from you Configuration
//I have injected Configuration provider service into my controller
Expires = DateTime.UtcNow.AddMinutes(Convert.ToDouble(Configuration["Jwt:ExpiryTimeInMinutes"])),
//algorithm to sign the token
SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature)
};
var token = tokenHandler.CreateToken(tokenDescriptor);
var tokenString = tokenHandler.WriteToken(token);
return Ok(new
{
token = tokenString
});
}
return BadRequest("Wrong Username or password");
}
now you need to Add Authentication to your services in your ConfigureServices inside your startup.cs to add JWT authentication as your default authentication service like this:
services.AddAuthentication(x =>
{
x.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
x.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(cfg =>
{
cfg.RequireHttpsMetadata = false;
cfg.SaveToken = true;
cfg.TokenValidationParameters = new TokenValidationParameters()
{
//ValidateIssuerSigningKey = true,
IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(configuration["JWT:Encryptionkey"])),
ValidateAudience = false,
ValidateLifetime = true,
ValidIssuer = configuration["Jwt:Issuer"],
//ValidAudience = Configuration["Jwt:Audience"],
//IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["JWT:Key"])),
};
});
now you can add policies to your authorization services like this:
services.AddAuthorization(options =>
{
options.AddPolicy("YourPolicyNameHere",
policy => policy.RequireClaim("YourClaimNameHere"));
});
ALTERNATIVELY, You can also (not necessary) populate all of your claims from your database as this will only run once on your application startup and add them to policies like this:
services.AddAuthorization(async options =>
{
var ClaimList = await claimApplication.GetList(applicationClaim);
foreach (var item in ClaimList)
{
options.AddPolicy(item.ClaimCode, policy => policy.RequireClaim(item.ClaimCode));
}
});
now you can put the Policy filter on any of the methods that you want to be authorized like this:
[HttpPost("update")]
[Authorize(Policy = "ACC_UP")]
public async Task<IActionResult> Update([FromBody] UserRequestVM requestVm, CancellationToken ct)
{
//your logic goes here
}
Hope this helps
In my case the JWT is created by a separate API so ASP.NET need only decode and validate it. In contrast to the accepted answer we're using RSA which is a non-symmetric algorithm, so the SymmetricSecurityKey class mentioned above won't work.
Here's the result.
using Microsoft.IdentityModel.Protocols;
using Microsoft.IdentityModel.Protocols.OpenIdConnect;
using Microsoft.IdentityModel.Tokens;
using System;
using System.IdentityModel.Tokens.Jwt;
using System.Threading;
using System.Threading.Tasks;
public static async Task<JwtSecurityToken> VerifyAndDecodeJwt(string accessToken)
{
try
{
var configurationManager = new ConfigurationManager<OpenIdConnectConfiguration>($"{securityApiOrigin}/.well-known/openid-configuration", new OpenIdConnectConfigurationRetriever());
var openIdConfig = await configurationManager.GetConfigurationAsync(CancellationToken.None);
var validationParameters = new TokenValidationParameters()
{
ValidateLifetime = true,
ValidateAudience = false,
ValidateIssuer = false,
RequireSignedTokens = true,
IssuerSigningKeys = openIdConfig.SigningKeys,
};
new JwtSecurityTokenHandler().ValidateToken(accessToken, validationParameters, out var validToken);
// threw on invalid, so...
return validToken as JwtSecurityToken;
}
catch (Exception ex)
{
logger.Info(ex.Message);
return null;
}
}
I think you should use some 3d party server to support the JWT token and there is no out of the box JWT support in WEB API 2.
However there is an OWIN project for supporting some format of signed token (not JWT). It works as a reduced OAuth protocol to provide just a simple form of authentication for a web site.
You can read more about it e.g. here.
It's rather long, but most parts are details with controllers and ASP.NET Identity that you might not need at all. Most important are
Step 9: Add support for OAuth Bearer Tokens Generation
Step 12: Testing the Back-end API
There you can read how to set up endpoint (e.g. "/token") that you can access from frontend (and details on the format of the request).
Other steps provide details on how to connect that endpoint to the database, etc. and you can chose the parts that you require.
You no need to work with weird JwtSecurityTokenHandler API
Use JwtUtils Nuget package with simple API
var claims = new Dictionary<string, object>
{
{ "exp", 1639942616 },
{ "uname", "i.a.ivanov" },
{ "claim1", "claim1_value" },
{ "claims_array", new [] {"claim_item1", "claim_item2"}}
};
string token = JWT.HS256.Create(claims, "{TOKEN_SECRET}");
You can follow this code for token controller or for more details you can visit here : How to Secure API using JWT Tokens. Building CRUD API using JWT Tokens with ASP.NET Core and Entity Framework Core and Swagger
From here you can learn to use JWT Token in a very easy way
using JWTToken.Models;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.IdentityModel.Tokens;
using System;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
using System.Threading.Tasks;
namespace JWTToken.Controllers
{
[Route("api/[controller]")]
[ApiController]
public class TokenController : ControllerBase
{
public IConfiguration _configuration;
private readonly InventoryContext _context;
public TokenController(IConfiguration config, InventoryContext context)
{
_configuration = config;
_context = context;
}
[HttpPost]
public async Task<IActionResult> Post(UserInfo _userData)
{
if (_userData != null && _userData.Email != null && _userData.Password != null)
{
var user = await GetUser(_userData.Email, _userData.Password);
if (user != null)
{
//create claims details based on the user information
var claims = new[] {
new Claim(JwtRegisteredClaimNames.Sub, _configuration["Jwt:Subject"]),
new Claim(JwtRegisteredClaimNames.Jti, Guid.NewGuid().ToString()),
new Claim(JwtRegisteredClaimNames.Iat, DateTime.UtcNow.ToString()),
new Claim("Id", user.UserId.ToString()),
new Claim("FirstName", user.FirstName),
new Claim("LastName", user.LastName),
new Claim("UserName", user.UserName),
new Claim("Email", user.Email)
};
var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_configuration["Jwt:Key"]));
var signIn = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
var token = new JwtSecurityToken(_configuration["Jwt:Issuer"], _configuration["Jwt:Audience"], claims, expires: DateTime.UtcNow.AddDays(1), signingCredentials: signIn);
return Ok(new JwtSecurityTokenHandler().WriteToken(token));
}
else
{
return BadRequest("Invalid credentials");
}
}
else
{
return BadRequest();
}
}
private async Task<UserInfo> GetUser(string email, string password)
{
return await _context.UserInfos.FirstOrDefaultAsync(u => u.Email == email && u.Password == password);
}
}
}

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