Medidata.MAuth is a framework that provides support for authenticating web services and applications with the Medidata HMAC protocol, MAuth.
The MAuth protocol provides a fault-tolerant, service-to-service authentication scheme for Medidata and third-party applications that use web services to communicate. The Authentication Service and integrity algorithm is based on digital signatures encrypted and decrypted with a private/public key pair.
The Authentication Service has two responsibilities. It provides message integrity and provenance validation by verifying a message sender's signature; its other task is to manage public keys. Each public key is associated with an application and is used to authenticate message signatures. The private key corresponding to the public key in the Authentication Service is stored by the application making a signed request; the request is encrypted with this private key. The Authentication Service has no knowledge of the application's private key, only its public key.
The framework is divided into separate semi-dependent NuGet packages to provide only the functionality which you need in your application. Below you can find the description of each individual packages.
A core package for the MAuth protocol. This package contains the core functionality which used by the other MAuth authentication protocol-specific components. This package also can be used standalone if you want to sign HTTP/HTTPS requests with Medidata MAuth keys using the .NET HttpClient message handler mechanism.
The package recommended in client applications where the application is required to issue MAuth-signed requests to an MAuth-enabled service.
This package contains an OWIN middleware to validate signed HTTP requests with the Medidata MAuth protocol. The middleware communicates with an MAuth server in order to confirm the validity of the request authentication header.
Include this package in your OWIN-enabled application if you want to authenticate the incoming requests signed with the MAuth protocol.
Similar to the Owin package this package has the ASP.NET Core-specific middleware that validates signed HTTP requests incoming to the application.
You can add this package in your ASP.NET Core web api application if you would like to authenticate your incoming requests signed with the MAuth protocol.
The package contains an HTTP message handler to validate signed HTTP requests with the Medidata MAuth protocol. The handler communicates with an MAuth server in order to confirm the validity of the request authentication header.
Include this package in your WebAPI application if you want to authenticate the incoming requests signed with the MAuth protocol.
Below you can find some information and examples on getting started using the framework.
Depending on your needs you can install either the Core package only (for signing requests), or the Owin or WebApi packages as well if you want to authenticate incoming requests.
The installation is as usual with NuGet.
For signing:
nuget install Medidata.MAuth.Core
Or in case of the authenticating, either
nuget install Medidata.MAuth.Owin
or
nuget install Medidata.MAuth.WebApi
For all of these you can use the Visual Studio Package Manager as well.
The Owin, AspNetCore and WebApi packages are dependent on the Core package, therefore it will be installed automatically in those cases.
In order to sign outgoing requests, an MAuthSigningHandler class is provided in the Core package. This handler
accepts an MAuthSigningOptions instance which stores all the necessary settings for the signing process.
An example:
using Medidata.MAuth.Core;
using Medidata.MAuth.Core.Models;
public async Task<HttpResponseMessage> SignAndSendRequest(HttpRequestMessage request)
{
var signingHandler = new MAuthSigningHandler(new MAuthSigningOptions()
{
ApplicationUuid = new Guid("7c872d75-986b-4c61-bb17-f2569d42bfb0"),
// The following can be either a path to the key file or the contents of the file itself
PrivateKey = "ClientPrivateKey.pem",
// Enumerations of signing protocols, if not provided defaults to `MAuthVersion.MWS`for sign-in.
SignVersions = MAuthVersion.MWS | MAuthVersion.MWSV2
});
using (var client = new HttpClient(signingHandler))
{
return await client.SendAsync(request);
}
}The SignVersions parameter can be used to specify which protocol version to sign outgoing requests with:
SignVersions = MAuthVersion.MWS: signs with theMWSprotocol only.SignVersions = MAuthVersion.MWS | MAuthVersion.MWSV2: signs with both theMWSand theMWSV2protocol. If not supplied, it signs with theMWSprotocol by default.
Signing with MWSV2 protocol supports query string.
The example above is creating a new instance of a HttpClient with the handler responsible for signing the
requests and sends the request to its designation. Finally it returns the response from the remote server.
The MAuthSigningOptions has the following properties to determine the required settings:
| Name | Description |
|---|---|
| ApplicationUuid | Determines the unique identifier of the client application used for the MAuth service authentication requests. This uuid needs to be registered with the MAuth Server in order for the authenticating server application to be able to authenticate the signed request. |
| PrivateKey | Determines the RSA private key of the client for signing a request. This key must be in a PEM ASN.1 format. The value of this property can be set as a valid path to a readable key file as well. |
| SignVersions | (optional) Enumerations of MAuth protocol versions to sign requests. If not supplied, defaults to MWS. |
If your application implements the OWIN-specific or ASP.NET Core pipeline, you can wire in the MAuthMiddleware
provided by the Owin and AspNetCore NuGet packages.
The setting and usage is as follows in case of OWIN (in the application's Startup class):
With the update of MAuth V2 protocol, the authentication will first check for mauth header with MWSV2 and if not found then only fallback to authenticate for MWS version.
Also, there is options of DisableV1, which is false by default and when we are ready to disable authentication of V1 protocl i.e. MWS version, then we need to pass this option too as true.
using Medidata.MAuth.Owin;
public class Startup
{
public void Configuration(IAppBuilder app)
{
app.UseMAuthAuthentication(options =>
{
options.ApplicationUuid = new Guid("a419de8f-d759-4db9-b9a7-c2cd14174987");
options.MAuthServiceUrl = new Uri("https://mauth.imedidata.com");
options.AuthenticateRequestTimeoutSeconds = 3;
options.MAuthServiceRetryPolicy = MAuthServiceRetryPolicy.RetryOnce;
options.HideExceptionsAndReturnUnauthorized = true;
options.PrivateKey = "ServerPrivateKey.pem";
options.Bypass = (request) => request.Uri.AbsolutePath.StartsWith("/allowed");
// when ready to disable authentication of V1 protococl
options.DisableV1 = true;
});
}
}For enabling the logging from Owin application, the following configuration will need to be added or updated:
<configuration>
<system.diagnostics>
<switches>
<add name="Microsoft.Owin" value="Information, Error, Warning" />
</switches>
</system.diagnostics>
</configuration>A similar way can be implemented for ASP.NET Core (also in the Startup class):
using Medidata.MAuth.AspNetCore;
public class Startup
{
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
app.UseMAuthAuthentication(options =>
{
options.ApplicationUuid = new Guid("a419de8f-d759-4db9-b9a7-c2cd14174987");
options.MAuthServiceUrl = new Uri("https://mauth.imedidata.com");
options.AuthenticateRequestTimeoutSeconds = 3;
options.MAuthServiceRetryPolicy = MAuthServiceRetryPolicy.RetryOnce;
options.HideExceptionsAndReturnUnauthorized = true;
options.PrivateKey = "ServerPrivateKey.pem";
options.Bypass = (request) => request.Uri.AbsolutePath.StartsWith("/allowed");
// when ready to disable authentication of V1 protococl
options.DisableV1 = true;
});
}
}The middlewares take an MAuthMiddlewareOptions instance to set up the authentication:
| Name | Description |
|---|---|
| ApplicationUuid | Determines the unique identifier of the server application used for the MAuth service authentication requests. This uuid needs to be registered with the MAuth Server in order to use it. |
| MAuthServiceUrl | Determines the endpoint of the MAuth authentication service. This endpoint is used by the authentication process to verify the validity of the signed request. |
| PrivateKey | Determines the RSA private key of the server application for the authentication requests. This key must be in a PEM ASN.1 format. The value of this property can be set as a valid path to a readable key file as well. |
| AuthenticateRequestTimeoutSeconds | An optional parameter that determines the timeout in seconds for the MAuth authentication request - the MAuth component will try to reach the MAuth server for this duration before it throws an exception. If not specified, the default value will be 3 seconds. |
| MAuthServiceRetryPolicy | The policy for the retry attempts when communicating with the MAuth service. The following policies can be used: NoRetry (no retries), RetryOnce (one additional attempt), RetryTwice (two additional attempts) and Agressive (9 additional attempts) - the default value is RetryOnce. |
| HideExceptionsAndReturnUnauthorized | An optional parameter that determines if the middleware should swallow all exceptions and return an empty HTTP response with a status code Unauthorized (401) in case of any errors (including authentication and validation errors). The default is true. |
| Bypass | Determines a function which evaluates if a given request should bypass the MAuth authentication. |
| DisableV1 | Determines the boolean value which controls whether to disable the signing requests with MAuthVersion.MWS requests or not. If not supplied, this default value is false. |
The HideExceptionsAndReturnUnauthorized parameter is useful (if set to false) when you have an exception handler
mechanism (for example a logger) in your middleware pipeline. In this case the MAuth middleware won't swallow the
exceptions but will throw them with full stack trace and details of the problem - as every authentication errors will
throw a Medidata.MAuth.Core.AuthenticationException you can still return a Unauthorized (401) HTTP status code in
those cases.
In the other hand, if you don't use any exception handling mechanism, it is recommended to leave this feature disabled
as setting this to false can possibly lead to exposing sensitive details about your application and the
authentication process. Leaving this parameter as true will result the middleware to return a Unauthorized (401) HTTP
status code for every error without showing any details.
The Bypass function takes a IOwinRequest in case of OWIN and an HttpRequest instance for ASP.NET Core and
should produce true as a result, if the given request satisfies the conditions to bypass the authentication;
otherwise it should result false therefore an authentication attempt will occur. If no Bypass predicate provided
in the options, every request will be authenticated by default.
When authentication of V1 requests needs to be disabled, then DisableV1 should be passed as true.
If your application does not use the OWIN or ASP.NET Core middleware infrastructure, but it uses the ASP.NET WebAPI
framework, the WebApi package provides an MAuthAuthenticatingHandler which can be assigned to WebAPI routes or
the global handler collection in order to automatically authenticate incoming requests.
For a global registration (that is, use MAuth authentication for all requests), you can register the handler as below
(in your WebApiConfig class):
using Medidata.MAuth.WebApi;
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
var options = new MAuthWebApiOptions()
{
ApplicationUuid = new Guid("a419de8f-d759-4db9-b9a7-c2cd14174987"),
MAuthServiceUrl = new Uri("https://mauth.imedidata.com"),
AuthenticateRequestTimeoutSeconds = 3,
MAuthServiceRetryPolicy = MAuthServiceRetryPolicy.RetryOnce,
HideExceptionsAndReturnUnauthorized = true,
PrivateKey = "ServerPrivateKey.pem",
// when ready to disable authentication of V1 protococl
options.DisableV1 = true
// if loggerfactory is present
options.loggerfactory = new Microsoft.Extensions.Logging.LoggerFactory(); // or provide the existing loggerfactory
};
config.MessageHandlers.Add(new MAuthAuthenticatingHandler(options));
}
}Alternatively, you can add the authenticating handler to a specific route when you define the route:
using Medidata.MAuth.WebApi;
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
var options = // See the previous example
config.Routes.MapHttpRoute(
name: "Route1",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional },
constraints: null,
handler: new MAuthAuthenticatingHandler(options)
);
}
}In the examples above, the MAuthWebApiOptions instance has the same properties as the OWIN- and
ASP.NET Core-specific MAuthMiddlewareOptions.
The framework is licensed under the MIT licensing terms.
The current target is .NET Framework 4.6.1 - this means that you have to use at least this target framework version in your project in order to make Medidata.MAuth work for you.
Yes, for signing outgoing requests you can use the library with any framework which implements the .NET Standard 2.0 and onwards; additionally we support the ASP.NET Core App 2.1 and onwards with a middleware for authenticating the incoming requests.
In the latest version of 4.0.0, we are using the available dotnet security System.Security.Cryptography which works for both .NET Framework 4.6.1 and .NET Standard 2.0 when using the V2 protocol. However, to also support the V1 protcol, we are still maintaining the BouncyCastle library as mentioned below.
On the .NET Framework side (WebAPI, Owin, Core) we are using the latest version (as of date 1.81) of the BouncyCastle library; on the .NET Standard side (Core, AspNetCore) we are using the portable fork of the BouncyCastle library.
In this version we have removed the property DisableV1 from MAuthSigningOptions. Instead, we have added new option as
SignVersions in MAuthSigningOptions which takes enumeration values of MAuth protcol versions MWS and/ or MWSV2 protocol.
If this option is not provided, then it will sign in by MWS protocol as default.
In this version we have added support for V2 protocol which uses MCC-Authentication as MAuthHeader and MCC-Time as
MAuthTimeHeader. And, this V2 protocol supports for signing and authenticating url with query string parameters.
For Signing, we added two new options in MAuthSigningOptions: MAuthVersion which is mandatory and takes enumeration
value of MAuthVersion.MWSV2 for V2 protocol or MAuthVersion.MWS for continue of using V1 protocol.
Another option DisableV1 is false by default if not provided. But, it is needed to provide as true when the client
need to sign on by no more supporting V1 protocol.
Also while authentication, the logic defaults to check for V2 protcol header MWSV2 and if fails then only fallback to
check for V1 protocol header for MWS. Also, MAuthOptionsBase includes new option as DisableV1 which is false by
default and need to be passed as true if the authenticating client no longer wants to support V1 protocol.
In this version we have only one major and a minor change: from this version the MAuthSigningHandler is accepting an
MAuthSigningOptions instance instead of an MAuthOptions instance (which in turn set to be an abstract class).
This change was necessary because the MAuthOptions object contains the MAuthServiceUrl property, which is not required
for signing, but it had to be set to a valid Url nonetheless.
The other underlying change is that in the OWIN middleware the infrastructure provided request body stream gets replaced
with a MemoryStream in cases when the original body stream is not seekable. This change was necessary, because in
order to authenticate the request we need to read the body, but if the body stream is not seekable we are not able to
restore it for the subsequent middlewares to read. Typical example for this is when the OWIN selfhost infrastructure
is used as it wraps the original stream in a non-seekable version.
Yes, all the ASP.NET WebApi handler and the Owin and ASP.NET Core middlewares support caching of the ApplicationInfo from the MAuth server in
order to not overload it with client information requests (and gradually improve the response times from the middlewares).
The cache expiration will be set according to the response cache header (max-age) from the MAuth server - or if this
information not provided, it will be 1 hour by default for successful requests (i.e. valid application uuids).
The documentation for the MAuthServiceRetryPolicy.Agressive retry policy says that it is not recommended for production use. What is the reason for this?
This policy will make the number of requests to the MAuth service to an overall 10 attempts. We believe that the chance to receive a successful response from the MAuth service is gradually decreasing by the number of attempts (the more the clients are sending requests to a presumably overloaded server the less the chance for a successful response) - therefore we do not recommend to use this policy in any production scenario.