支持多个相同类型的AuthenticationSchemes

Question

我正在使用 IdentityServer4 并尝试添加多个相同类型的外部提供程序，在我的例子中是 OpenIdConnect。但是我遇到了一些问题。

services.AddAuthentication()
// Azure AD
.AddOpenIdConnect("oidc", "Azure AD", x =>
{
    x.SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme;
    x.SignOutScheme = IdentityServerConstants.SignoutScheme;
    x.ClientId = "some-client-id";
    x.Authority = "https://login.microsoftonline.com/common";
    x.ResponseType = OpenIdConnectResponseType.IdToken;
    x.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = false
    };
})
// Identity Server
.AddOpenIdConnect("oidc", "My Other Identity Server", x =>
{
    x.SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme;
    x.SignOutScheme = IdentityServerConstants.SignoutScheme;
    x.ClientId = "some-other-client-id";
    x.Authority = "http://localhost:6000"; //Another Identity Server I want to treat as external provider
    x.RequireHttpsMetadata = false;
    x.ResponseType = OpenIdConnectResponseType.IdToken;
    x.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = true
    };
});

原因：

Scheme already exists: oidc
   at Microsoft.AspNetCore.Authentication.AuthenticationOptions.AddScheme(String name, Action`1 configureBuilder)
   at Microsoft.AspNetCore.Authentication.AuthenticationBuilder.<>c__DisplayClass4_0`2.<AddScheme>b__0(AuthenticationOptions o)
   at Microsoft.Extensions.Options.ConfigureNamedOptions`1.Configure(String name, TOptions options)
   at Microsoft.Extensions.Options.OptionsFactory`1.Create(String name)
   at Microsoft.Extensions.Options.OptionsManager`1.<>c__DisplayClass5_0.<Get>b__0()
   at System.Lazy`1.ViaFactory(LazyThreadSafetyMode mode)
   at System.Lazy`1.ExecutionAndPublication(LazyHelper executionAndPublication, Boolean useDefaultConstructor)
   at System.Lazy`1.CreateValue()
   at Microsoft.Extensions.Options.OptionsCache`1.GetOrAdd(String name, Func`1 createOptions)
   at Microsoft.Extensions.Options.OptionsManager`1.Get(String name)
   at Microsoft.Extensions.Options.OptionsManager`1.get_Value()
   at Microsoft.AspNetCore.Authentication.AuthenticationSchemeProvider..ctor(IOptions`1 options)

services.AddAuthentication()
// Azure AD
.AddOpenIdConnect("oidc", "Azure AD", x =>
{
    x.SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme;
    x.SignOutScheme = IdentityServerConstants.SignoutScheme;
    x.ClientId = "some-client-id";
    x.Authority = "https://login.microsoftonline.com/common";
    x.ResponseType = OpenIdConnectResponseType.IdToken;
    x.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = false
    };
})
// Identity Server
.AddOpenIdConnect("oidc-idserver", "My Other Identity Server", x =>
{
    x.SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme;
    x.SignOutScheme = IdentityServerConstants.SignoutScheme;
    x.ClientId = "some-other-client-id";
    x.Authority = "http://localhost:6000"; //Another Identity Server I want to treat as external provider
    x.RequireHttpsMetadata = false;
    x.ResponseType = OpenIdConnectResponseType.IdToken;
    x.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = true
    };
});

如果我给他们不同的方案，那么当外部提供者回发时，我会得到以下异常。

原因：

Exception: Correlation failed.
  Microsoft.AspNetCore.Authentication.RemoteAuthenticationHandler+<HandleRequestAsync>d__12.MoveNext()

Answer 1

正如评论者所建议的，解决方案是添加特定的 CallbackPath 和 SignedOutCallbackPath，以便中间件可以知道哪个外部提供程序正在运行。

services.AddAuthentication()
// Azure AD
.AddOpenIdConnect("oidc", "Azure AD", x =>    
{
    x.SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme;
    x.SignOutScheme = IdentityServerConstants.SignoutScheme;
    x.ClientId = "some-client-id";
    x.Authority = "https://login.microsoftonline.com/common";
    x.ResponseType = OpenIdConnectResponseType.IdToken;
    x.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = false
    };

    // Callbacks for middleware to properly correlate
    x.CallbackPath = new PathString("/signin-oidc-az");
    x.SignedOutCallbackPath = new PathString("/signout-oidc-az");
})
// Identity Server
.AddOpenIdConnect("oidc-idserver", "My Other Identity Server", x =>    
{
    x.SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme;
    x.SignOutScheme = IdentityServerConstants.SignoutScheme;
    x.ClientId = "some-other-client-id";
    x.Authority = "http://localhost:6000"; //Another Identity Server I want to treat as external provider
    x.RequireHttpsMetadata = false;
    x.ResponseType = OpenIdConnectResponseType.IdToken;
    x.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = true
    };

    // Callbacks for middleware to properly correlate
    x.CallbackPath = new PathString("/signin-oidc-so");
    x.SignedOutCallbackPath = new PathString("/signout-oidc-so");
});