#### [Abblix\.Oidc\.Server](https://www.abblix.com/en/docs/api/abblix-oidc-server 'index')
### [Abblix\.Oidc\.Server\.Endpoints\.Token\.Grants](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Endpoints.Token.Grants 'Abblix\.Oidc\.Server\.Endpoints\.Token\.Grants')

## BackChannelAuthenticationGrantHandler Class

Handles the authorization process for backchannel authentication requests under the Client\-Initiated Backchannel
Authentication \(CIBA\) grant type\.
This handler validates the token request based on the backchannel authentication flow, ensuring
that the client is authorized and that the user has been authenticated before tokens are issued\.
Supports both short\-polling \(immediate response\) and long\-polling \(holds connection until auth completes\)\.

```csharp
public class BackChannelAuthenticationGrantHandler : Abblix.Oidc.Server.Endpoints.Token.Grants.IAuthorizationGrantHandler, Abblix.Oidc.Server.Common.Interfaces.IGrantTypeInformer
```

Inheritance [System\.Object](https://learn.microsoft.com/en-us/dotnet/api/system.object 'System\.Object') → BackChannelAuthenticationGrantHandler

Implements [IAuthorizationGrantHandler](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Endpoints.Token.Grants.IAuthorizationGrantHandler 'Abblix\.Oidc\.Server\.Endpoints\.Token\.Grants\.IAuthorizationGrantHandler'), [IGrantTypeInformer](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Common.Interfaces.IGrantTypeInformer 'Abblix\.Oidc\.Server\.Common\.Interfaces\.IGrantTypeInformer')
### Constructors

## BackChannelAuthenticationGrantHandler\(IBackChannelRequestStorage, TimeProvider, IOptions\<OidcOptions\>, IServiceProvider, IBackChannelLongPollingService, IHttpContextAccessor\) Constructor {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor)}

Handles the authorization process for backchannel authentication requests under the Client\-Initiated Backchannel
Authentication \(CIBA\) grant type\.
This handler validates the token request based on the backchannel authentication flow, ensuring
that the client is authorized and that the user has been authenticated before tokens are issued\.
Supports both short\-polling \(immediate response\) and long\-polling \(holds connection until auth completes\)\.

```csharp
public BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage storage, System.TimeProvider timeProvider, Microsoft.Extensions.Options.IOptions<Abblix.Oidc.Server.Common.Configuration.OidcOptions> options, System.IServiceProvider serviceProvider, Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService? statusNotifier=null, Microsoft.AspNetCore.Http.IHttpContextAccessor? httpContextAccessor=null);
```
#### Parameters

###### `storage` [IBackChannelRequestStorage](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.Interfaces\.IBackChannelRequestStorage') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor).storage}

Service for storing and retrieving backchannel authentication requests\.

###### `timeProvider` [System\.TimeProvider](https://learn.microsoft.com/en-us/dotnet/api/system.timeprovider 'System\.TimeProvider') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor).timeProvider}

Provides access to the current time\.

###### `options` [Microsoft\.Extensions\.Options\.IOptions&lt;](https://learn.microsoft.com/en-us/dotnet/api/microsoft.extensions.options.ioptions-1 'Microsoft\.Extensions\.Options\.IOptions\`1')[OidcOptions](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Common.Configuration.OidcOptions 'Abblix\.Oidc\.Server\.Common\.Configuration\.OidcOptions')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/microsoft.extensions.options.ioptions-1 'Microsoft\.Extensions\.Options\.IOptions\`1') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor).options}

Configuration options for backchannel authentication including long\-polling settings\.

###### `serviceProvider` [System\.IServiceProvider](https://learn.microsoft.com/en-us/dotnet/api/system.iserviceprovider 'System\.IServiceProvider') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor).serviceProvider}

Service provider for resolving mode\-specific grant processors\.

###### `statusNotifier` [IBackChannelLongPollingService](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService 'Abblix\.Oidc\.Server\.Features\.BackChannelAuthentication\.Interfaces\.IBackChannelLongPollingService') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor).statusNotifier}

Notifier for long\-polling status changes \(null if long\-polling disabled\)\.

###### `httpContextAccessor` [Microsoft\.AspNetCore\.Http\.IHttpContextAccessor](https://learn.microsoft.com/en-us/dotnet/api/microsoft.aspnetcore.http.ihttpcontextaccessor 'Microsoft\.AspNetCore\.Http\.IHttpContextAccessor') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.BackChannelAuthenticationGrantHandler(Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelRequestStorage,System.TimeProvider,Microsoft.Extensions.Options.IOptions_Abblix.Oidc.Server.Common.Configuration.OidcOptions_,System.IServiceProvider,Abblix.Oidc.Server.Features.BackChannelAuthentication.Interfaces.IBackChannelLongPollingService,Microsoft.AspNetCore.Http.IHttpContextAccessor).httpContextAccessor}

Accessor for HTTP context to retrieve cancellation token\.
### Properties

## BackChannelAuthenticationGrantHandler\.GrantTypesSupported Property {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.GrantTypesSupported}

Specifies the grant types supported by this handler, specifically the "CIBA" \(Client\-Initiated Backchannel
Authentication\) grant type\.
This property ensures that the handler is only invoked for the specific grant type it supports\.

```csharp
public System.Collections.Generic.IEnumerable<string> GrantTypesSupported { get; }
```

Implements [GrantTypesSupported](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Common.Interfaces.IGrantTypeInformer#Abblix.Oidc.Server.Common.Interfaces.IGrantTypeInformer.GrantTypesSupported 'Abblix\.Oidc\.Server\.Common\.Interfaces\.IGrantTypeInformer\.GrantTypesSupported')

#### Property Value
[System\.Collections\.Generic\.IEnumerable&lt;](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.ienumerable-1 'System\.Collections\.Generic\.IEnumerable\`1')[System\.String](https://learn.microsoft.com/en-us/dotnet/api/system.string 'System\.String')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.ienumerable-1 'System\.Collections\.Generic\.IEnumerable\`1')
### Methods

## BackChannelAuthenticationGrantHandler\.AuthorizeAsync\(TokenRequest, ClientInfo\) Method {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.AuthorizeAsync(Abblix.Oidc.Server.Model.TokenRequest,Abblix.Oidc.Server.Features.ClientInformation.ClientInfo)}

Processes the authorization request by verifying the authentication request ID and checking the status of the
associated backchannel authentication request\. Supports both short\-polling \(immediate response\) and optional
long\-polling \(holds connection until authentication completes or timeout\)\.

```csharp
public System.Threading.Tasks.Task<Abblix.Utils.Result<Abblix.Oidc.Server.Endpoints.Token.Interfaces.AuthorizedGrant,Abblix.Oidc.Server.Common.OidcError>> AuthorizeAsync(Abblix.Oidc.Server.Model.TokenRequest request, Abblix.Oidc.Server.Features.ClientInformation.ClientInfo clientInfo);
```
#### Parameters

###### `request` [TokenRequest](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Model.TokenRequest 'Abblix\.Oidc\.Server\.Model\.TokenRequest') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.AuthorizeAsync(Abblix.Oidc.Server.Model.TokenRequest,Abblix.Oidc.Server.Features.ClientInformation.ClientInfo).request}

The token request containing the authentication request ID and other parameters\.

###### `clientInfo` [ClientInfo](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Features.ClientInformation.ClientInfo 'Abblix\.Oidc\.Server\.Features\.ClientInformation\.ClientInfo') {#Abblix.Oidc.Server.Endpoints.Token.Grants.BackChannelAuthenticationGrantHandler.AuthorizeAsync(Abblix.Oidc.Server.Model.TokenRequest,Abblix.Oidc.Server.Features.ClientInformation.ClientInfo).clientInfo}

Information about the client making the request, used to validate client identity
            and determine token delivery mode \(poll/ping/push\)\.

Implements [AuthorizeAsync\(TokenRequest, ClientInfo\)](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Endpoints.Token.Grants.IAuthorizationGrantHandler#Abblix.Oidc.Server.Endpoints.Token.Grants.IAuthorizationGrantHandler.AuthorizeAsync(Abblix.Oidc.Server.Model.TokenRequest,Abblix.Oidc.Server.Features.ClientInformation.ClientInfo) 'Abblix\.Oidc\.Server\.Endpoints\.Token\.Grants\.IAuthorizationGrantHandler\.AuthorizeAsync\(Abblix\.Oidc\.Server\.Model\.TokenRequest, Abblix\.Oidc\.Server\.Features\.ClientInformation\.ClientInfo\)')

#### Returns
[System\.Threading\.Tasks\.Task&lt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')[Abblix\.Utils\.Result&lt;](https://learn.microsoft.com/en-us/dotnet/api/abblix.utils.result-2 'Abblix\.Utils\.Result\`2')[AuthorizedGrant](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Endpoints.Token.Interfaces.AuthorizedGrant 'Abblix\.Oidc\.Server\.Endpoints\.Token\.Interfaces\.AuthorizedGrant')[,](https://learn.microsoft.com/en-us/dotnet/api/abblix.utils.result-2 'Abblix\.Utils\.Result\`2')[OidcError](https://www.abblix.com/en/docs/api/abblix-oidc-server/Abblix.Oidc.Server.Common.OidcError 'Abblix\.Oidc\.Server\.Common\.OidcError')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/abblix.utils.result-2 'Abblix\.Utils\.Result\`2')[&gt;](https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.task-1 'System\.Threading\.Tasks\.Task\`1')  
Either an authorized grant if authentication succeeded, or an error indicating why the request failed
\(authorization\_pending, access\_denied, expired\_token, slow\_down, or invalid\_grant\)\.

### Remarks

<strong>Behavior by Authentication Status:</strong>
- Authenticated:
- Pending (short-polling):
- Pending (long-polling):
- Denied:
- Expired/Not Found:
- Rate Limited:

Long-polling reduces latency (0-1s vs 0-5s) and server load (1-4 req/min vs 12 req/min) by holding the
connection open until authentication completes instead of requiring repeated polling.