private async Task <bool> SendAuthorizationResponseAsync(OpenIdConnectResponse response, AuthenticationTicket ticket = null)
{
var request = Context.GetOpenIdConnectRequest();
Context.SetOpenIdConnectResponse(response);
response.SetProperty(OpenIdConnectConstants.Properties.MessageType,
OpenIdConnectConstants.MessageTypes.AuthorizationResponse);
// Note: as this stage, the request may be null (e.g if it couldn't be extracted from the HTTP request).
var notification = new ApplyAuthorizationResponseContext(Context, Scheme, Options, ticket, request, response)
{
RedirectUri = request?.GetProperty <string>(OpenIdConnectConstants.Properties.ValidatedRedirectUri),
ResponseMode = request?.ResponseMode
};
// If the response_mode parameter was not specified, try to infer it.
if (string.IsNullOrEmpty(notification.ResponseMode) && !string.IsNullOrEmpty(notification.RedirectUri))
{
notification.ResponseMode =
request.IsFormPostResponseMode() ? OpenIdConnectConstants.ResponseModes.FormPost :
request.IsFragmentResponseMode() ? OpenIdConnectConstants.ResponseModes.Fragment :
request.IsQueryResponseMode() ? OpenIdConnectConstants.ResponseModes.Query : null;
}
await Provider.ApplyAuthorizationResponse(notification);
if (notification.Result != null)
{
if (notification.Result.Handled)
{
Logger.LogDebug("The authorization request was handled in user code.");
return(true);
}
else if (notification.Result.Skipped)
{
Logger.LogDebug("The default authorization request handling was skipped from user code.");
return(false);
}
}
// Directly display an error page if redirect_uri cannot be used to
// redirect the user agent back to the client application.
if (!string.IsNullOrEmpty(response.Error) && string.IsNullOrEmpty(notification.RedirectUri))
{
// Apply a 400 status code by default.
Response.StatusCode = 400;
if (Options.ApplicationCanDisplayErrors)
{
// Return false to allow the rest of
// the pipeline to handle the request.
return(false);
}
Logger.LogInformation("The authorization response was successfully returned " +
"as a plain-text document: {Response}.", response);
return(await SendNativePageAsync(response));
}
// At this stage, throw an exception if the request was not properly extracted.
if (request == null)
{
throw new InvalidOperationException("The authorization response cannot be returned.");
}
// Attach the request state to the authorization response.
if (string.IsNullOrEmpty(response.State))
{
response.State = request.State;
}
// Note: a dictionary is deliberately not used here to allow multiple parameters with the
// same name to be specified. While initially not allowed by the core OAuth2 specification,
// this is now accepted by derived drafts like the OAuth2 token exchange specification.
// For consistency, multiple parameters with the same name are also supported by this endpoint.
var parameters = new List <KeyValuePair <string, string> >();
foreach (var parameter in response.GetParameters())
{
var values = (string[])parameter.Value;
if (values == null)
{
continue;
}
foreach (var value in values)
{
parameters.Add(new KeyValuePair <string, string>(parameter.Key, value));
}
}
// Note: at this stage, the redirect_uri parameter MUST be trusted.
switch (notification.ResponseMode)
{
case OpenIdConnectConstants.ResponseModes.FormPost:
{
Logger.LogInformation("The authorization response was successfully returned to " +
"'{RedirectUri}' using the form post response mode: {Response}.",
notification.RedirectUri, response);
using (var buffer = new MemoryStream())
using (var writer = new StreamWriter(buffer))
{
writer.WriteLine("<!doctype html>");
writer.WriteLine("<html>");
writer.WriteLine("<body>");
// While the redirect_uri parameter should be guarded against unknown values
// by OpenIdConnectServerProvider.ValidateAuthorizationRequest,
// it's still safer to encode it to avoid cross-site scripting attacks
// if the authorization server has a relaxed policy concerning redirect URIs.
writer.WriteLine($@"<form name=""form"" method=""post"" action=""{Options.HtmlEncoder.Encode(notification.RedirectUri)}"">");
foreach (var parameter in parameters)
{
var key = Options.HtmlEncoder.Encode(parameter.Key);
var value = Options.HtmlEncoder.Encode(parameter.Value);
writer.WriteLine($@"<input type=""hidden"" name=""{key}"" value=""{value}"" />");
}
writer.WriteLine(@"<noscript>Click here to finish the authorization process: <input type=""submit"" /></noscript>");
writer.WriteLine("</form>");
writer.WriteLine("<script>document.form.submit();</script>");
writer.WriteLine("</body>");
writer.WriteLine("</html>");
writer.Flush();
Response.StatusCode = 200;
Response.ContentLength = buffer.Length;
Response.ContentType = "text/html;charset=UTF-8";
Response.Headers["Cache-Control"] = "no-cache";
Response.Headers["Pragma"] = "no-cache";
Response.Headers["Expires"] = "-1";
buffer.Seek(offset: 0, loc: SeekOrigin.Begin);
await buffer.CopyToAsync(Response.Body, 4096, Context.RequestAborted);
return(true);
}
}
case OpenIdConnectConstants.ResponseModes.Fragment:
{
Logger.LogInformation("The authorization response was successfully returned to " +
"'{RedirectUri}' using the fragment response mode: {Response}.",
notification.RedirectUri, response);
var location = notification.RedirectUri;
var appender = new OpenIdConnectServerHelpers.Appender(location, '#');
foreach (var parameter in parameters)
{
appender.Append(parameter.Key, parameter.Value);
}
Response.Redirect(appender.ToString());
return(true);
}
case OpenIdConnectConstants.ResponseModes.Query:
{
Logger.LogInformation("The authorization response was successfully returned to " +
"'{RedirectUri}' using the query response mode: {Response}.",
notification.RedirectUri, response);
var location = notification.RedirectUri;
foreach (var parameter in parameters)
{
location = QueryHelpers.AddQueryString(location, parameter.Key, parameter.Value);
}
Response.Redirect(location);
return(true);
}
default:
{
Logger.LogError("The authorization request was rejected because the 'response_mode' " +
"parameter was invalid: {ResponseMode}.", request.ResponseMode);
return(await SendNativePageAsync(new OpenIdConnectResponse
{
Error = OpenIdConnectConstants.Errors.InvalidRequest,
ErrorDescription = "The specified 'response_mode' parameter is not supported."
}));
}
}
}
/// <summary> /// Represents an event called before the authorization response is returned to the caller. /// </summary> /// <param name="context">The context instance associated with this event.</param> /// <returns>A <see cref="Task"/> that can be used to monitor the asynchronous operation.</returns> public virtual Task ApplyAuthorizationResponse(ApplyAuthorizationResponseContext context) => OnApplyAuthorizationResponse(context);