/// <summary>
/// Called when receiving an access token. An application may use this context
/// to deserialize the token using a custom format and to skip the default logic using
/// <see cref="BaseContext{OpenIdConnectServerOptions}.HandleResponse"/>.
/// </summary>
/// <param name="context">The context of the event carries information in and results out.</param>
/// <returns>Task to enable asynchronous execution</returns>
public virtual Task ReceiveAccessToken(ReceiveAccessTokenContext context) => OnReceiveAccessToken(context);
private async Task <AuthenticationTicket> ReceiveAccessTokenAsync(string token, OpenIdConnectMessage request)
{
try {
var notification = new ReceiveAccessTokenContext(Context, Options, request, token)
{
DataFormat = Options.AccessTokenFormat,
Issuer = Context.GetIssuer(Options),
SecurityTokenHandler = Options.AccessTokenHandler,
SignatureProvider = Options.SignatureProvider,
SigningKey = Options.SigningCredentials.Select(credentials => credentials.SigningKey)
.FirstOrDefault()
};
// Sets the default deserializer used to resolve the
// authentication ticket corresponding to the access token.
notification.Deserializer = payload => {
var handler = notification.SecurityTokenHandler as ISecurityTokenValidator;
if (handler == null)
{
return(Task.FromResult(notification.DataFormat?.Unprotect(payload)));
}
// Create new validation parameters to validate the security token.
// ValidateAudience and ValidateLifetime are always set to false:
// if necessary, the audience and the expiration can be validated
// in InvokeValidationEndpointAsync or InvokeTokenEndpointAsync.
var parameters = new TokenValidationParameters {
IssuerSigningKey = notification.SigningKey,
ValidIssuer = notification.Issuer,
ValidateAudience = false,
ValidateLifetime = false
};
SecurityToken securityToken;
var principal = handler.ValidateToken(payload, parameters, out securityToken);
// Parameters stored in AuthenticationProperties are lost
// when the identity token is serialized using a security token handler.
// To mitigate that, they are inferred from the claims or the security token.
var properties = new AuthenticationProperties {
ExpiresUtc = securityToken.ValidTo,
IssuedUtc = securityToken.ValidFrom
};
var audiences = principal.FindAll(JwtRegisteredClaimNames.Aud);
if (audiences.Any())
{
properties.SetAudiences(audiences.Select(claim => claim.Value));
}
var usage = principal.FindFirst(OpenIdConnectConstants.Extra.Usage);
if (usage != null)
{
properties.SetUsage(usage.Value);
}
if (principal.Claims.Any(claim => claim.Type == OpenIdConnectConstants.Extra.Confidential))
{
properties.Items[OpenIdConnectConstants.Extra.Confidential] = "true";
}
return(Task.FromResult(new AuthenticationTicket(principal, properties, Options.AuthenticationScheme)));
};
await Options.Provider.ReceiveAccessToken(notification);
// Directly return the authentication ticket if one
// has been provided by ReceiveAccessToken.
// Treat a non-null ticket like an implicit HandleResponse call.
if (notification.HandledResponse || notification.AuthenticationTicket != null)
{
if (notification.AuthenticationTicket == null)
{
return(null);
}
// Ensure the received ticket is an access token.
if (!notification.AuthenticationTicket.IsAccessToken())
{
Logger.LogVerbose("The received token was not an access token: {0}.", token);
return(null);
}
return(notification.AuthenticationTicket);
}
else if (notification.Skipped)
{
return(null);
}
var ticket = await notification.DeserializeTicketAsync(token);
if (ticket == null)
{
return(null);
}
// Ensure the received ticket is an access token.
if (!ticket.IsAccessToken())
{
Logger.LogVerbose("The received token was not an access token: {0}.", token);
return(null);
}
return(ticket);
}
catch (Exception exception) {
Logger.LogWarning("An exception occured when deserializing an access token.", exception);
return(null);
}
}