Very simple SAML 2.0 "consumer" implementation in C#. It's a SAML client library, not a SAML server, allows adding SAML single-sign-on to your ASP.NET app, but not to provide auth services to other apps.
Consists of one short C# file you can throw into your project (or install via nuget) and start using it. Originally forked from OneLogin's .NET SAML library, but we had to fix a lot of stuff...
SAML workflow has 2 steps:
- User is redirected to the SAML provider (where he authenticates)
- User is redirected back to your app, where you validate the payload
Here's how you do it:
//specify the SAML provider url here, aka "Endpoint"
var samlEndpoint = "http://saml-provider-that-we-use.com/login/";
var request = new AuthRequest(
"http://www.myapp.com", //put your app's "unique ID" here
"http://www.myapp.com/SamlConsume" //assertion Consumer Url - the redirect URL where the provider will send authenticated users
);
//generate the provider URL
string url = request.GetRedirectUrl(samlEndpoint);
//then redirect your user to the above "url" var
//for example, like this:
Response.Redirect(url);
User is sent back to your app - you need to validate the SAML response ("assertion") that you recieved via POST.
Here's an example of how you do it in ASP.NET MVC
//ASP.NET MVC action method... But you can easily modify the code for Web-forms etc.
public ActionResult SamlConsume()
{
//specify the certificate that your SAML provider has given to you
string samlCertificate = @"-----BEGIN CERTIFICATE-----
BLAHBLAHBLAHBLAHBLAHBLAHBLAHBLAHBLAHBLAHBLAHBLAH123543==
-----END CERTIFICATE-----";
Saml.Response samlResponse = new Response(samlCertificate);
samlResponse.LoadXmlFromBase64(Request.Form["SAMLResponse"]); //SAML providers usually POST the data into this var
if (samlResponse.IsValid())
{
//WOOHOO!!! user is logged in
//YAY!
//Some more optional stuff for you
//lets extract username/firstname etc
string username, email, firstname, lastname;
try
{
username = samlResponse.GetNameID();
email = samlResponse.GetEmail();
firstname = samlResponse.GetFirstName();
lastname = samlResponse.GetLastName();
}
catch(Exception ex)
{
//insert error handling code
//no, really, please do
return null;
}
//user has been authenticated, put your code here, like set a cookie or something...
//or call FormsAuthentication.SetAuthCookie() or something
}
}
I've published this to Nuget.
Install-Package AspNetSaml
This will simply add the cs-file to the root of your project.
A version of this library has been used for years in production in our helpdesk app.