ASP.NET Universal Providers - Do they automatically provide SQL Azure Retry Logic? - asp.net

Regarding the ASP.NET Universal Providers (System.Web.Providers), do they automatically offer the retry logic when used with SQL Azure? For example in my code I call:
Membership.CreateUser
If that fails because of a Azure's transient error, does the library automatically handle the situation and retry the operation? Or should I manually handle the exception + do the retry?
The following question implies that the reply logic is built-in, but is there a place where I could confirm this, like some home page of these providers or the source code?

I don't see anywhere it retries again after fail. DefaultMembershipProvider uses simple entity framework AddObject, unless you implement CustomMembershipProvider.
internal static User CreateUser(MembershipEntities ctx, Guid id,
string userName, Guid appId, bool isAnon)
{
User user = new User();
user.UserId = id;
user.ApplicationId = appId;
user.LastActivityDate = DateTime.UtcNow;
user.UserName = userName;
user.IsAnonymous = isAnon;
ctx.Users.AddObject(user);
User user1 = user;
return user1;
}

Related

How do I create a ClaimsPrincipal in my Blazor/.NetCore "Session"?

Background: I have an old MVC app that I'm experimenting with migrating to a shiny new Blazor app. Blazor seems to tick a lot of boxes for me here. Wunderbar. For clarity this is the solution template in VS2022 where there's a WASM, a .Net Core host, and a shared project. I will have plenty of api calls that need to be secured as well as UI that will be affected by various authorization policies (eg show/hide admin features).
I have a table of users with an ID and hashed password.
I can't get Blazor to use its native authentication/authorization processes with my existing store.
My latest attempt was to create an AccountController on the server app (inherits ControllerBase) and put in a Login method that gets the username and password from a json body for the moment. I have successfully ported the old authentication mechanism and I have my user that I have verified the password for. I now want to use Claims and a ClaimsPrincipal to store some of the things about the user, nothing too complex.
How do I put my ClaimsPrincipal into the app such that the WASM UI can see it AND future calls to api controllers (or ControllerBase controllers) will see it?
I have found hundreds of examples that use built-in scaffolding that lets it use EF to create tables and things but I need to use my existing stores and I can't find anything that joins the dots on how to connect the WASM and the server side.
I have read about and implemented and around the place, and tried some #authorize around the place but my WASM just doesn't know about the authenticated user.
In my login controller I have attempted a bunch of different approaches:
I implemented a custom AuthenticationStateProvider, got it into the controller via DI, called the AuthenticationStateChanged() and for the lifecycle of that one controller call I can see my HttpContext.User gets the new identity. But the WASM doesn't, and if I hit the same method again the User is null again
I tried to implement a SignInManager. This never worked well and my reading suggests that it's not compatible
I discovered ControllerBase.SignIn() which hasn't helped either
HttpContext.SignInAsync() with Cookie authentication (because that was the example I found)
I tried setting HttpContext.User directly (and tried combining that one call with the AuthenticationStateProvider implementation simultaneously)
I tried creating a fresh solution from template to pick through it, but it would appear to be reliant on hacking up my EF DataContext. I just want to find how I tell the whole contraption "Here's a ClaimsPrincipal" and have that work in both the WASM and api controllers.
I'm also not excited to have a dependency on the Duende stuff - I don't see what it brings to the table. I don't really need a whole identity provider, I already have my own code for authorizing against the database I just need to get my very boring ClaimsPrincipal into my app.
Am I going at this all wrong? Has my many years of "old school" experience stopped me from seeing a modern way of doing this? Am I trying to force cool new stuff to behave like clunky old stuff? Yes I'd love to switch to Google/Facebook/Twitter/MS authorization but that's not an option, I have passwords in a database.
You need to build a custom AuthenticationHandler.
Here's the relevant bits of one of mine (see credits at bottom for where I lifted some of the code). You'll need to pick out the pieces from the code to make your work. Ask if you have any specific problems.
The custom AuthenticationHandler looks up your user in your database and if authenticated, builds a standard ClaimsPrincipal object and adds it to the security header. You can then use the standard Authorization and AuthenticationStateProvider.
public class AppAuthenticationHandler : AuthenticationHandler<AppAuthOptions>
{
private const string AuthorizationHeaderName = "Authorization";
private const string BasicSchemeName = "BlazrAuth";
//this is my custom identity database
private IIdentityService _identityService;
public AppAuthenticationHandler(IOptionsMonitor<AppAuthOptions> options, IIdentityService identityService, ILoggerFactory logger, UrlEncoder encoder, ISystemClock clock)
: base(options, logger, encoder, clock)
{
_identityService = identityService;
}
protected override async Task<AuthenticateResult> HandleAuthenticateAsync()
{
await Task.Yield();
// Check the Headers and make sure we have a valid set
if (!Request.Headers.ContainsKey(AuthorizationHeaderName))
return AuthenticateResult.Fail("No Authorization Header detected");
if (!AuthenticationHeaderValue.TryParse(Request.Headers[AuthorizationHeaderName], out AuthenticationHeaderValue? headerValue))
return AuthenticateResult.Fail("No Authorization Header detected");
if (!BasicSchemeName.Equals(headerValue.Scheme, StringComparison.OrdinalIgnoreCase))
return AuthenticateResult.Fail("No Authorization Header detected");
if (headerValue is null || headerValue.Parameter is null)
return AuthenticateResult.Fail("No Token detected");
// Get the User Guid from the security token
var headerValueBytes = Convert.FromBase64String(headerValue.Parameter);
var userpasswordstring = Encoding.UTF8.GetString(headerValueBytes);
// This will give you a string like this "me#you.com:password"
if (youcantdecodethestring ))
return AuthenticateResult.Fail("Invalid Token submitted");
// Get the user data from your database
var principal = await this.GetUserAsync(userId);
if (principal is null)
return AuthenticateResult.Fail("User does not Exist");
// Create and return an AuthenticationTicket
var ticket = new AuthenticationTicket(principal, Scheme.Name);
return AuthenticateResult.Success(ticket);
}
// method to get the user from the database and retuen a ClaimsPrincipal
public async Task<ClaimsPrincipal?> GetUserAsync(Guid Id)
{
// Get the user object from the database
var result = await _identityService.GetIdentityAsync(Id);
// Construct a ClaimsPrincipal object if the have a valid user
if (result.Success && result.Identity is not null)
return new ClaimsPrincipal(result.Identity);
// No user so return null
return null;
}
}
You can construct a ClaimsIdentity like this:
var identity = new ClaimsIdentity(new[]
{
new Claim(ClaimTypes.Sid, record.Id.ToString()),
new Claim(ClaimTypes.Name, record.Name),
new Claim(ClaimTypes.Role, record.Role)
}, "MyIdentityProvider");
public class AppAuthOptions : AuthenticationSchemeOptions
{
public string Realm = "BlazrAuth";
}
The service registration:
public static class AuthServicesCollection
{
public static void AddAppAuthServerServices(this IServiceCollection services)
{
services.AddAuthentication("BlazrAuth").AddScheme<AppAuthOptions, AppAuthenticationHandler>("BlazrAuth", null);
services.AddScoped<IIdentityService, IdentityService>();
}
}
Credits: Some of this code was derived from: https://harrison-technology.net/

Port over existing MVC user authentication to Azure functions

I have an old web application which is using ASP.net with the build in cookie based authentication which has the standard ASP.net SQL tables for storing the users credentials.
This is currently running as an Azure web app, but I was toying with the idea of trying to go serverless as per this example creating a ReactJs SPA hosting on blob storage to try and keep costs down and also improve performance without breaking the bank.
https://learn.microsoft.com/en-us/azure/architecture/reference-architectures/serverless/web-app
I was wondering if it is possible to port over the existing ASP.net authentication to Azure functions, to instead return a JWT (JSON Web Token) which could be passed back in the headers to handle authenticated requests.
When I have tried this in the past I have failed misserably, so I was wondering if anyone knows if it is possible?
I've seen this article, which seems to talk about Azure functions doing authentication, but with Azure AD, which I don't think is right for what I need.
https://blogs.msdn.microsoft.com/stuartleeks/2018/02/19/azure-functions-and-app-service-authentication/
The answer is kind of. What I mean by this is that you can use your existing database and many of the same libraries, but you can't port over the code configuration. The default authentication for Functions is either 1) The default API tokens or 2) one of the EasyAuth providers baked into App Services which is in the guide you linked. Currently, any other solution you'll need to setup yourself.
Assuming you go with the JWT option, you'll need to turn off all of the built-in authentication for Functions. This includes setting your HttpRequest functions to AuthorizationLevel.Anonymous.
At a basic level You'll need to create two things. A function to issue tokens, and either a DI service or a custom input binding to check them.
Issuing tokens
The Functions 2.x+ runtime is on .NET Core so I'm gong to borrow some code from this blog post that describes using JWTs with Web API. It uses System.IdentityModel.Tokens.Jwt to generate a token, which we could then return from the Function.
public SecurityToken Authenticate(string username, string password)
{
//replace with your user validation
var user = _users.SingleOrDefault(x => x.Username == username && x.Password == password);
// return null if user not found
if (user == null)
return null;
// authentication successful so generate jwt token
var tokenHandler = new JwtSecurityTokenHandler();
var key = Encoding.ASCII.GetBytes(_appSettings.Secret);
var tokenDescriptor = new SecurityTokenDescriptor
{
Subject = new ClaimsIdentity(new Claim[]
{
new Claim(ClaimTypes.Name, user.Id.ToString())
}),
Expires = DateTime.UtcNow.AddDays(7),
SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature)
};
return tokenHandler.CreateToken(tokenDescriptor);
}
Validating Tokens
There are several guides out there for validating JWT within Azure Functions. I like this one from Ben Morris: https://www.ben-morris.com/custom-token-authentication-in-azure-functions-using-bindings/ (source code). It describes authenticating with either a custom input binding or with DI. Between the two, DI is the preferred option, unless there is a specific reason you need to use a binding. Here again, its the Microsoft.IdentityModel.JsonWebTokens and System.IdentityModel.Tokens.Jwt libraries that you'll need to do the bulk of the work.
public class ExampleHttpFunction
{
private readonly IAccessTokenProvider _tokenProvider;
public ExampleHttpFunction(IAccessTokenProvider tokenProvider)
{
_tokenProvider = tokenProvider;
}
[FunctionName("ExampleHttpFunction")]
public IActionResult Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = "example")] HttpRequest req, ILogger log)
{
var result = _tokenProvider.ValidateToken(req);
if (result.Status == AccessTokenStatus.Valid)
{
log.LogInformation($"Request received for {result.Principal.Identity.Name}.");
return new OkResult();
}
else
{
return new UnauthorizedResult();
}
}
}

Implementing active authentication using ADFS

I am working on the authentication with Active Directory using ADFS.
While searching, I got few articles to accomplish this requirement, but they are suggesting to redirect the Login page of application to Login page of ADFS and then come back.
Redirecting to ADFS Login page is not suggested as per user experience.
Can anyone help me to find out the solution to authenticate with active directory using ADFS behind the scene ? So, everything will be handled by application code, not by ADFS login page.
Please advise.
Please let me know if you have any concern or query or if you need more information.
The reason those articles suggest you redirect (using WS-Federation protocol) to the ADFS login page is because it allows you to set up federation to other identity providers (allow an external company' employees to use their own credentials to log in to your application).
What you want can be done using the WS-Trust protocol, but you'll give up (or have to implement yourself) the possibility to federate.
ADFS exposes endpoints like /adfs/services/trust/13/usernamemixed that you can talk to to get a security token. Something like below should get you going.
public class UserNameWSTrustBinding : WS2007HttpBinding
{
public UserNameWSTrustBinding()
{
Security.Mode = SecurityMode.TransportWithMessageCredential;
Security.Message.EstablishSecurityContext = false;
Security.Message.ClientCredentialType = MessageCredentialType.UserName;
}
}
private static SecurityToken GetSamlToken(string username, string password)
{
var factory = new WSTrustChannelFactory(new UserNameWSTrustBinding(), "https://yourdomain.com/adfs/services/trust/13/UsernameMixed")
{
TrustVersion = TrustVersion.WSTrust13
};
factory.Credentials.UserName.UserName = username;
factory.Credentials.UserName.Password = password;
var rst = new RequestSecurityToken
{
RequestType = RequestTypes.Issue,
AppliesTo = new EndpointReference("https://yourdomain.com/yourservice"),
KeyType = KeyTypes.Bearer
};
var channel = factory.CreateChannel();
return channel.Issue(rst);
}

SignalR: how to survive accidental page refresh

Imagine there is a chat web app between two browser clients using SignalR. What is the best approach to survive accidental F5 hit done by one of the client?
Here is described the strategy using cookies together with custom SignalR IConnectionIdFactory. But the author of the article says "The SignalR team doesn’t recommend this action". So what is the recommended architecture?
You can map the temporary connection id to a permanent user id/name (which might be stored in your DB) when the client connects. See the ShootR example which does this (last time I checked, at least).
For example, you could keep a ConcurrentDictionary of objects representing users that you track active users with and associate them with their connection ids in OnConnected (and revert this in OnDisconnected) similar to this:
private static readonly ConcurrentDictionary<string, User> Users
= new ConcurrentDictionary<string, User>();
public override Task OnConnected() {
string userName = Context.User.Identity.Name;
string connectionId = Context.ConnectionId;
var user = Users.GetOrAdd(userName, _ => new User {
Name = userName,
ConnectionIds = new HashSet<string>()
});
lock (user.ConnectionIds) {
user.ConnectionIds.Add(connectionId);
}
return base.OnConnected();
}

.Net 2.0 ServiceController.GetServices()

I've got a website that has windows authentication enable on it. From a page in the website, the users have the ability to start a service that does some stuff with the database.
It works fine for me to start the service because I'm a local admin on the server. But I just had a user test it and they can't get the service started.
My question is:
Does anyone know of a way to get a list of services on a specified computer by name using a different windows account than the one they are currently logged in with?
I really don't want to add all the users that need to start the service into a windows group and set them all to a local admin on my IIS server.....
Here's some of the code I've got:
public static ServiceControllerStatus FindService()
{
ServiceControllerStatus status = ServiceControllerStatus.Stopped;
try
{
string machineName = ConfigurationManager.AppSettings["ServiceMachineName"];
ServiceController[] services = ServiceController.GetServices(machineName);
string serviceName = ConfigurationManager.AppSettings["ServiceName"].ToLower();
foreach (ServiceController service in services)
{
if (service.ServiceName.ToLower() == serviceName)
{
status = service.Status;
break;
}
}
}
catch(Exception ex)
{
status = ServiceControllerStatus.Stopped;
SaveError(ex, "Utilities - FindService()");
}
return status;
}
My exception comes from the second line in the try block. Here's the error:
System.InvalidOperationException:
Cannot open Service Control Manager on
computer 'server.domain.com'. This
operation might require other
privileges. --->
System.ComponentModel.Win32Exception:
Access is denied --- End of inner
exception stack trace --- at
System.ServiceProcess.ServiceController.GetDataBaseHandleWithAccess(String
machineName, Int32
serviceControlManaqerAccess) at
System.ServiceProcess.ServiceController.GetServicesOfType(String
machineName, Int32 serviceType) at
TelemarketingWebSite.Utilities.StartService()
Thanks for the help/info
Note: This doesn't address enumerating services as a different user, but given the broader description of what you're doing, I think it's a good answer.
I think you can simplify this a lot, and possibly avoid part of the security problem, if you go directly to the service of interest. Instead of calling GetServices, try this:
string machineName = ConfigurationManager.AppSettings["ServiceMachineName"];
string serviceName = ConfigurationManager.AppSettings["ServiceName"];
ServiceController service = new ServiceController( serviceName, machineName );
return service.Status;
This connects directly to the service of interest and bypasses the enumeration/search step. Therefore, it doesn't require the caller to have the SC_MANAGER_ENUMERATE_SERVICE right on the Service Control Manager (SCM), which remote users do not have by default. It does still require SC_MANAGER_CONNECT, but according to MSDN that should be granted to remote authenticated users.
Once you have found the service of interest, you'll still need to be able to stop and start it, which your remote users probably don't have rights to do. However, it's possible to modify the security descriptor (DACL) on individual services, which would let you grant your remote users access to stop and start the service without requiring them to be local admins. This is done via the SetNamedSecurityInfo API function. The access rights you need to grant are SERVICE_START and SERVICE_STOP. Depending on exactly which groups these users belong to, you might also need to grant them GENERIC_READ. All of these rights are described in MSDN.
Here is some C++ code that would perform this setup, assuming the users of interest are in the "Remote Service Controllers" group (which you would create) and the service name is "my-service-name". Note that if you wanted to grant access to a well-known group such as Users (not necessarily a good idea) rather than a group you created, you need to change TRUSTEE_IS_GROUP to TRUSTEE_IS_WELL_KNOWN_GROUP.
The code has no error checking, which you would want to add. All three functions that can fail (Get/SetNamedSecurityInfo and SetEntriesInAcl) return 0 to indicate success.
Another Note: You can also set a service's security descriptor using the SC tool, which can be found under %WINDIR%\System32, but that doesn't involve any programming.
#include "windows.h"
#include "accctrl.h"
#include "aclapi.h"
int main()
{
char serviceName[] = "my-service-name";
char userGroup[] = "Remote Service Controllers";
// retrieve the security info
PACL pDacl = NULL;
PSECURITY_DESCRIPTOR pDescriptor = NULL;
GetNamedSecurityInfo( serviceName, SE_SERVICE,
DACL_SECURITY_INFORMATION, NULL, NULL,
&pDacl, NULL, &pDescriptor );
// add an entry to allow the users to start and stop the service
EXPLICIT_ACCESS access;
ZeroMemory( &access, sizeof(access) );
access.grfAccessMode = GRANT_ACCESS;
access.grfAccessPermissions = SERVICE_START | SERVICE_STOP;
access.Trustee.TrusteeForm = TRUSTEE_IS_NAME;
access.Trustee.TrusteeType = TRUSTEE_IS_GROUP;
access.Trustee.ptstrName = userGroup;
PACL pNewDacl;
SetEntriesInAcl( 1, &access, pDacl, &pNewDacl );
// write the changes back to the service
SetNamedSecurityInfo( serviceName, SE_SERVICE,
DACL_SECURITY_INFORMATION, NULL, NULL,
pNewDacl, NULL );
LocalFree( pNewDacl );
LocalFree( pDescriptor );
}
This could also be done from C# using P/Invoke, but that's a bit more work.
If you still specifically want to be able to enumerate services as these users, you need to grant them the SC_MANAGER_ENUMERATE_SERVICE right on the SCM. Unfortunately, according to MSDN, the SCM's security can only be modified on Windows Server 2003 sp1 or later.
Thanks for that line of code Charlie. Here's what I ended up doing. I got the idea from this website: http://www.codeproject.com/KB/cs/svcmgr.aspx?display=Print
I also had to add the account I'm accessing this as to the Power Users group on the server.
public static ServiceControllerStatus FindService()
{
ServiceControllerStatus status = ServiceControllerStatus.Stopped;
try
{
string machineName = ConfigurationManager.AppSettings["ServiceMachineName"];
string serviceName = ConfigurationManager.AppSettings["ServiceName"].ToLower();
ImpersonationUtil.Impersonate();
ServiceController service = new ServiceController(serviceName, machineName);
status = service.Status;
}
catch(Exception ex)
{
status = ServiceControllerStatus.Stopped;
SaveError(ex, "Utilities - FindService()");
}
return status;
}
And here's my other class with the ImpersonationUtil.Impersonate():
public static class ImpersonationUtil
{
public static bool Impersonate()
{
string logon = ConfigurationManager.AppSettings["ImpersonationUserName"];
string password = ConfigurationManager.AppSettings["ImpersonationPassword"];
string domain = ConfigurationManager.AppSettings["ImpersonationDomain"];
IntPtr token = IntPtr.Zero;
IntPtr tokenDuplicate = IntPtr.Zero;
WindowsImpersonationContext impersonationContext = null;
if (LogonUser(logon, domain, password, 2, 0, ref token) != 0)
if (DuplicateToken(token, 2, ref tokenDuplicate) != 0)
impersonationContext = new WindowsIdentity(tokenDuplicate).Impersonate();
//
return (impersonationContext != null);
}
[DllImport("advapi32.dll", CharSet = CharSet.Auto)]
public static extern int LogonUser(string lpszUserName, string lpszDomain, string lpszPassword, int dwLogonType, int dwLogonProvider, ref IntPtr phToken);
[DllImport("advapi32.dll", CharSet = System.Runtime.InteropServices.CharSet.Auto, SetLastError = true)]
public extern static int DuplicateToken(IntPtr hToken, int impersonationLevel, ref IntPtr hNewToken);
}
You can try using ASP.NET impersonation in your web.config file and specify a user account that has the appropriate permissions:
<system.web>
<identity impersonate="true" userName="Username" password="Password" />
</system.web
Take a look at this article on MSDN. I believe there are other options that do not require storing the password in the web.config file such as placing it in a registry key instead.
This will cause the ASP.NET worker process to run under the context of the specified user instead of the user logged into the web application. However, this poses a security issue and I would strongly rethink your design. You may want to consider having the ASP.NET web page in turn fire off a request to some other process that actually controls the services, even another windows service or write the request to a database table that the windows service polls periodically.

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