I\'ve got a Web API project fronted by Angular, and I want to secure it using a JWT token. I\'ve already got user/pass validation happening, so I think i just need to implement
I ended-up having to take a information from several different places to create a solution that works for me (in reality, the beginnings of a production viable solution - but it works!)
I got rid of JwtAuthForWebAPI (though I did borrow one piece from it to allow requests with no Authorization header to flow through to WebAPI Controller methods not guarded by [Authorize]).
Instead I'm using Microsoft's JWT Library (JSON Web Token Handler for the Microsoft .NET Framework - from NuGet).
In my authentication method, after doing the actual authentication, I create the string version of the token and pass it back along with the authenticated name (the same username passed into me, in this case) and a role which, in reality, would likely be derived during authentication.
Here's the method:
[HttpPost]
public LoginResult PostSignIn([FromBody] Credentials credentials)
{
var auth = new LoginResult() { Authenticated = false };
if (TryLogon(credentials.UserName, credentials.Password))
{
var tokenDescriptor = new SecurityTokenDescriptor
{
Subject = new ClaimsIdentity(new[]
{
new Claim(ClaimTypes.Name, credentials.UserName),
new Claim(ClaimTypes.Role, "Admin")
}),
AppliesToAddress = ConfigurationManager.AppSettings["JwtAllowedAudience"],
TokenIssuerName = ConfigurationManager.AppSettings["JwtValidIssuer"],
SigningCredentials = new SigningCredentials(new
InMemorySymmetricSecurityKey(JwtTokenValidationHandler.SymmetricKey),
"http://www.w3.org/2001/04/xmldsig-more#hmac-sha256",
"http://www.w3.org/2001/04/xmlenc#sha256")
};
var tokenHandler = new JwtSecurityTokenHandler();
var token = tokenHandler.CreateToken(tokenDescriptor);
var tokenString = tokenHandler.WriteToken(token);
auth.Token = tokenString;
auth.Authenticated = true;
}
return auth;
}
UPDATE
There was a question about handling the token on subsequent requests. What I did was create a DelegatingHandler to try and read/decode the token, then create a Principal and set it into Thread.CurrentPrincipal and HttpContext.Current.User (you need to set it into both). Finally, I decorate the controller methods with the appropriate access restrictions.
Here's the meat of the DelegatingHandler:
private static bool TryRetrieveToken(HttpRequestMessage request, out string token)
{
token = null;
IEnumerable authzHeaders;
if (!request.Headers.TryGetValues("Authorization", out authzHeaders) || authzHeaders.Count() > 1)
{
return false;
}
var bearerToken = authzHeaders.ElementAt(0);
token = bearerToken.StartsWith("Bearer ") ? bearerToken.Substring(7) : bearerToken;
return true;
}
protected override Task SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
HttpStatusCode statusCode;
string token;
var authHeader = request.Headers.Authorization;
if (authHeader == null)
{
// missing authorization header
return base.SendAsync(request, cancellationToken);
}
if (!TryRetrieveToken(request, out token))
{
statusCode = HttpStatusCode.Unauthorized;
return Task.Factory.StartNew(() => new HttpResponseMessage(statusCode));
}
try
{
JwtSecurityTokenHandler tokenHandler = new JwtSecurityTokenHandler();
TokenValidationParameters validationParameters =
new TokenValidationParameters()
{
AllowedAudience = ConfigurationManager.AppSettings["JwtAllowedAudience"],
ValidIssuer = ConfigurationManager.AppSettings["JwtValidIssuer"],
SigningToken = new BinarySecretSecurityToken(SymmetricKey)
};
IPrincipal principal = tokenHandler.ValidateToken(token, validationParameters);
Thread.CurrentPrincipal = principal;
HttpContext.Current.User = principal;
return base.SendAsync(request, cancellationToken);
}
catch (SecurityTokenValidationException e)
{
statusCode = HttpStatusCode.Unauthorized;
}
catch (Exception)
{
statusCode = HttpStatusCode.InternalServerError;
}
return Task.Factory.StartNew(() => new HttpResponseMessage(statusCode));
}
Don't forget to add it into the MessageHandlers pipeline:
public static void Start()
{
GlobalConfiguration.Configuration.MessageHandlers.Add(new JwtTokenValidationHandler());
}
Finally, decorate your controller methods:
[Authorize(Roles = "OneRoleHere")]
[GET("/api/admin/settings/product/allorgs")]
[HttpGet]
public List GetAllOrganizations()
{
return QueryableDependencies.GetMergedOrganizations().ToList();
}
[Authorize(Roles = "ADifferentRoleHere")]
[GET("/api/admin/settings/product/allorgswithapproval")]
[HttpGet]
public List GetAllOrganizationsWithApproval()
{
return QueryableDependencies.GetMergedOrganizationsWithApproval().ToList();
}