private async Task <string> SerializeAccessTokenAsync( ClaimsPrincipal principal, AuthenticationProperties properties, OpenIdConnectRequest request, OpenIdConnectResponse response) { // Create a new principal containing only the filtered claims. // Actors identities are also filtered (delegation scenarios). principal = principal.Clone(claim => { // Never exclude the subject claim. if (string.Equals(claim.Type, OpenIdConnectConstants.Claims.Subject, StringComparison.OrdinalIgnoreCase)) { return(true); } // Claims whose destination is not explicitly referenced or doesn't // contain "access_token" are not included in the access token. if (!claim.HasDestination(OpenIdConnectConstants.Destinations.AccessToken)) { Logger.LogDebug("'{Claim}' was excluded from the access token claims.", claim.Type); return(false); } return(true); }); // Remove the destinations from the claim properties. foreach (var claim in principal.Claims) { claim.Properties.Remove(OpenIdConnectConstants.Properties.Destinations); } var identity = (ClaimsIdentity)principal.Identity; // Create a new ticket containing the updated properties and the filtered principal. var ticket = new AuthenticationTicket(principal, properties, Options.AuthenticationScheme); ticket.Properties.IssuedUtc = Options.SystemClock.UtcNow; ticket.Properties.ExpiresUtc = ticket.Properties.IssuedUtc + (ticket.GetAccessTokenLifetime() ?? Options.AccessTokenLifetime); ticket.SetUsage(OpenIdConnectConstants.Usages.AccessToken); ticket.SetAudiences(ticket.GetResources()); // Associate a random identifier with the access token. ticket.SetTicketId(Guid.NewGuid().ToString()); // Remove the unwanted properties from the authentication ticket. ticket.RemoveProperty(OpenIdConnectConstants.Properties.AccessTokenLifetime) .RemoveProperty(OpenIdConnectConstants.Properties.AuthorizationCodeLifetime) .RemoveProperty(OpenIdConnectConstants.Properties.ClientId) .RemoveProperty(OpenIdConnectConstants.Properties.CodeChallenge) .RemoveProperty(OpenIdConnectConstants.Properties.CodeChallengeMethod) .RemoveProperty(OpenIdConnectConstants.Properties.IdentityTokenLifetime) .RemoveProperty(OpenIdConnectConstants.Properties.Nonce) .RemoveProperty(OpenIdConnectConstants.Properties.RedirectUri) .RemoveProperty(OpenIdConnectConstants.Properties.RefreshTokenLifetime); var notification = new SerializeAccessTokenContext(Context, Options, request, response, ticket) { DataFormat = Options.AccessTokenFormat, Issuer = Context.GetIssuer(Options), SecurityTokenHandler = Options.AccessTokenHandler, SigningCredentials = Options.SigningCredentials.FirstOrDefault(key => key.Key is SymmetricSecurityKey) ?? Options.SigningCredentials.FirstOrDefault() }; await Options.Provider.SerializeAccessToken(notification); if (notification.HandledResponse || !string.IsNullOrEmpty(notification.AccessToken)) { return(notification.AccessToken); } else if (notification.Skipped) { return(null); } if (!ReferenceEquals(ticket, notification.Ticket)) { throw new InvalidOperationException("The authentication ticket cannot be replaced."); } if (notification.SecurityTokenHandler == null) { return(notification.DataFormat?.Protect(ticket)); } // At this stage, throw an exception if no signing credentials were provided. if (notification.SigningCredentials == null) { throw new InvalidOperationException("A signing key must be provided."); } // Extract the main identity from the principal. identity = (ClaimsIdentity)ticket.Principal.Identity; // Store the "unique_id" property as a claim. identity.AddClaim(OpenIdConnectConstants.Claims.JwtId, ticket.GetTicketId()); // Store the "usage" property as a claim. identity.AddClaim(OpenIdConnectConstants.Claims.Usage, ticket.GetUsage()); // Store the "confidentiality_level" property as a claim. var confidentiality = ticket.GetProperty(OpenIdConnectConstants.Properties.ConfidentialityLevel); if (!string.IsNullOrEmpty(confidentiality)) { identity.AddClaim(OpenIdConnectConstants.Claims.ConfidentialityLevel, confidentiality); } // Create a new claim per scope item, that will result // in a "scope" array being added in the access token. foreach (var scope in notification.Scopes) { identity.AddClaim(OpenIdConnectConstants.Claims.Scope, scope); } // Store the audiences as claims. foreach (var audience in notification.Audiences) { identity.AddClaim(OpenIdConnectConstants.Claims.Audience, audience); } // Extract the presenters from the authentication ticket. var presenters = notification.Presenters.ToArray(); switch (presenters.Length) { case 0: break; case 1: identity.AddClaim(OpenIdConnectConstants.Claims.AuthorizedParty, presenters[0]); break; default: Logger.LogWarning("Multiple presenters have been associated with the access token " + "but the JWT format only accepts single values."); // Only add the first authorized party. identity.AddClaim(OpenIdConnectConstants.Claims.AuthorizedParty, presenters[0]); break; } var token = notification.SecurityTokenHandler.CreateToken(new SecurityTokenDescriptor { Subject = identity, Issuer = notification.Issuer, SigningCredentials = notification.SigningCredentials, IssuedAt = notification.Ticket.Properties.IssuedUtc?.UtcDateTime, NotBefore = notification.Ticket.Properties.IssuedUtc?.UtcDateTime, Expires = notification.Ticket.Properties.ExpiresUtc?.UtcDateTime }); return(notification.SecurityTokenHandler.WriteToken(token)); }
private async Task <string> SerializeAccessTokenAsync( ClaimsPrincipal principal, AuthenticationProperties properties, OpenIdConnectMessage request, OpenIdConnectMessage response) { try { // properties.IssuedUtc and properties.ExpiresUtc // should always be preferred when explicitly set. if (properties.IssuedUtc == null) { properties.IssuedUtc = Options.SystemClock.UtcNow; } if (properties.ExpiresUtc == null) { properties.ExpiresUtc = properties.IssuedUtc + Options.AccessTokenLifetime; } properties.SetUsage(OpenIdConnectConstants.Usages.AccessToken); // Create a new principal containing only the filtered claims. // Actors identities are also filtered (delegation scenarios). principal = principal.Clone(claim => { // ClaimTypes.NameIdentifier and JwtRegisteredClaimNames.Sub are never excluded. if (string.Equals(claim.Type, ClaimTypes.NameIdentifier, StringComparison.Ordinal) || string.Equals(claim.Type, JwtRegisteredClaimNames.Sub, StringComparison.Ordinal)) { return(true); } // Claims whose destination is not explicitly referenced or // doesn't contain "token" are not included in the access token. return(claim.HasDestination(OpenIdConnectConstants.ResponseTypes.Token)); }); var identity = (ClaimsIdentity)principal.Identity; // Create a new ticket containing the updated properties and the filtered principal. var ticket = new AuthenticationTicket(principal, properties, Options.AuthenticationScheme); var notification = new SerializeAccessTokenContext(Context, Options, request, response, ticket) { Client = request.ClientId, Confidential = properties.IsConfidential(), DataFormat = Options.AccessTokenFormat, Issuer = Context.GetIssuer(Options), SecurityTokenHandler = Options.AccessTokenHandler, SigningCredentials = Options.SigningCredentials.FirstOrDefault() }; foreach (var audience in properties.GetResources()) { notification.Audiences.Add(audience); } foreach (var scope in properties.GetScopes()) { notification.Scopes.Add(scope); } // Sets the default access token serializer. notification.Serializer = payload => { if (notification.SecurityTokenHandler == null) { return(Task.FromResult(notification.DataFormat?.Protect(payload))); } // Extract the main identity from the principal. identity = (ClaimsIdentity)payload.Principal.Identity; // Store the "usage" property as a claim. identity.AddClaim(OpenIdConnectConstants.Extra.Usage, payload.Properties.GetUsage()); // If the ticket is marked as confidential, add a new // "confidential" claim in the security token. if (notification.Confidential) { identity.AddClaim(new Claim(OpenIdConnectConstants.Extra.Confidential, "true", ClaimValueTypes.Boolean)); } // Create a new claim per scope item, that will result // in a "scope" array being added in the access token. foreach (var scope in notification.Scopes) { identity.AddClaim(OpenIdConnectConstants.Claims.Scope, scope); } // Note: when used as an access token, a JWT token doesn't have to expose a "sub" claim // but the name identifier claim is used as a substitute when it has been explicitly added. // See https://tools.ietf.org/html/rfc7519#section-4.1.2 var subject = identity.FindFirst(JwtRegisteredClaimNames.Sub); if (subject == null) { var identifier = identity.FindFirst(ClaimTypes.NameIdentifier); if (identifier != null) { identity.AddClaim(JwtRegisteredClaimNames.Sub, identifier.Value); } } // Remove the ClaimTypes.NameIdentifier claims to avoid getting duplicate claims. // Note: the "sub" claim is automatically mapped by JwtSecurityTokenHandler // to ClaimTypes.NameIdentifier when validating a JWT token. // Note: make sure to call ToArray() to avoid an InvalidOperationException // on old versions of Mono, where FindAll() is implemented using an iterator. foreach (var claim in identity.FindAll(ClaimTypes.NameIdentifier).ToArray()) { identity.RemoveClaim(claim); } // Store the audiences as claims. foreach (var audience in notification.Audiences) { identity.AddClaim(JwtRegisteredClaimNames.Aud, audience); } // List the client application as an authorized party. if (!string.IsNullOrEmpty(notification.Client)) { identity.AddClaim(JwtRegisteredClaimNames.Azp, notification.Client); } var handler = notification.SecurityTokenHandler as JwtSecurityTokenHandler; if (handler != null) { var token = handler.CreateToken( subject: identity, issuer: notification.Issuer, signingCredentials: notification.SigningCredentials, issuedAt: payload.Properties.IssuedUtc.Value.UtcDateTime, notBefore: payload.Properties.IssuedUtc.Value.UtcDateTime, expires: payload.Properties.ExpiresUtc.Value.UtcDateTime); if (notification.SigningCredentials != null) { var x509SecurityKey = notification.SigningCredentials.Key as X509SecurityKey; if (x509SecurityKey != null) { // Note: unlike "kid", "x5t" is not automatically added by JwtHeader's constructor in IdentityModel for ASP.NET 5. // Though not required by the specifications, this property is needed for IdentityModel for Katana to work correctly. // See https://github.com/aspnet-contrib/AspNet.Security.OpenIdConnect.Server/issues/132 // and https://github.com/AzureAD/azure-activedirectory-identitymodel-extensions-for-dotnet/issues/181. token.Header[JwtHeaderParameterNames.X5t] = Base64UrlEncoder.Encode(x509SecurityKey.Certificate.GetCertHash()); } object identifier; if (!token.Header.TryGetValue(JwtHeaderParameterNames.Kid, out identifier) || identifier == null) { // When the token doesn't contain a "kid" parameter in the header, automatically // add one using the identifier specified in the signing credentials. identifier = notification.SigningCredentials.Kid; if (identifier == null) { // When no key identifier has been explicitly added by the developer, a "kid" is automatically // inferred from the hexadecimal representation of the certificate thumbprint (SHA-1). if (x509SecurityKey != null) { identifier = x509SecurityKey.Certificate.Thumbprint; } // When no key identifier has been explicitly added by the developer, a "kid" // is automatically inferred from the modulus if the signing key is a RSA key. var rsaSecurityKey = notification.SigningCredentials.Key as RsaSecurityKey; if (rsaSecurityKey != null) { // Only use the 40 first chars to match the identifier used by the JWKS endpoint. identifier = Base64UrlEncoder.Encode(rsaSecurityKey.Parameters.Modulus) .Substring(0, 40) .ToUpperInvariant(); } } token.Header[JwtHeaderParameterNames.Kid] = identifier; } } return(Task.FromResult(handler.WriteToken(token))); } else { var token = notification.SecurityTokenHandler.CreateToken(new SecurityTokenDescriptor { Claims = payload.Principal.Claims, Issuer = notification.Issuer, Audience = notification.Audiences.ElementAtOrDefault(0), SigningCredentials = notification.SigningCredentials, IssuedAt = notification.AuthenticationTicket.Properties.IssuedUtc.Value.UtcDateTime, NotBefore = notification.AuthenticationTicket.Properties.IssuedUtc.Value.UtcDateTime, Expires = notification.AuthenticationTicket.Properties.ExpiresUtc.Value.UtcDateTime }); // Note: the security token is manually serialized to prevent // an exception from being thrown if the handler doesn't implement // the SecurityTokenHandler.WriteToken overload returning a string. var builder = new StringBuilder(); using (var writer = XmlWriter.Create(builder, new XmlWriterSettings { Encoding = new UTF8Encoding(false), OmitXmlDeclaration = true })) { notification.SecurityTokenHandler.WriteToken(writer, token); } return(Task.FromResult(builder.ToString())); } }; await Options.Provider.SerializeAccessToken(notification); // Treat a non-null access token like an implicit HandleResponse call. if (notification.HandledResponse || !string.IsNullOrEmpty(notification.AccessToken)) { return(notification.AccessToken); } else if (notification.Skipped) { return(null); } // Allow the application to change the authentication // ticket from the SerializeAccessTokenAsync event. ticket = notification.AuthenticationTicket; ticket.Properties.CopyTo(properties); return(await notification.SerializeTicketAsync()); } catch (Exception exception) { Logger.LogWarning("An exception occured when serializing an access token.", exception); return(null); } }
private async Task <string> SerializeAccessTokenAsync( ClaimsPrincipal principal, AuthenticationProperties properties, OpenIdConnectMessage request, OpenIdConnectMessage response) { // properties.IssuedUtc and properties.ExpiresUtc // should always be preferred when explicitly set. if (properties.IssuedUtc == null) { properties.IssuedUtc = Options.SystemClock.UtcNow; } if (properties.ExpiresUtc == null) { properties.ExpiresUtc = properties.IssuedUtc + Options.AccessTokenLifetime; } // Create a new principal containing only the filtered claims. // Actors identities are also filtered (delegation scenarios). principal = principal.Clone(claim => { // Never exclude ClaimTypes.NameIdentifier. if (string.Equals(claim.Type, ClaimTypes.NameIdentifier, StringComparison.OrdinalIgnoreCase)) { return(true); } // Claims whose destination is not explicitly referenced or doesn't // contain "access_token" are not included in the access token. return(claim.HasDestination(OpenIdConnectConstants.Destinations.AccessToken)); }); var identity = (ClaimsIdentity)principal.Identity; // Create a new ticket containing the updated properties and the filtered principal. var ticket = new AuthenticationTicket(principal, properties, Options.AuthenticationScheme); ticket.SetUsage(OpenIdConnectConstants.Usages.AccessToken); ticket.SetAudiences(ticket.GetResources()); // By default, add the client_id to the list of the // presenters allowed to use the access token. if (!string.IsNullOrEmpty(request.ClientId)) { ticket.SetPresenters(request.ClientId); } var notification = new SerializeAccessTokenContext(Context, Options, request, response, ticket) { DataFormat = Options.AccessTokenFormat, Issuer = Context.GetIssuer(Options), SecurityTokenHandler = Options.AccessTokenHandler, SigningCredentials = Options.SigningCredentials.FirstOrDefault() }; await Options.Provider.SerializeAccessToken(notification); if (!string.IsNullOrEmpty(notification.AccessToken)) { return(notification.AccessToken); } if (notification.SecurityTokenHandler == null) { return(notification.DataFormat?.Protect(ticket)); } // Extract the main identity from the principal. identity = (ClaimsIdentity)ticket.Principal.Identity; // Store the "usage" property as a claim. identity.AddClaim(OpenIdConnectConstants.Claims.Usage, ticket.GetUsage()); // If the ticket is marked as confidential, add a new // "confidential" claim in the security token. if (ticket.IsConfidential()) { identity.AddClaim(new Claim(OpenIdConnectConstants.Claims.Confidential, "true", ClaimValueTypes.Boolean)); } // Create a new claim per scope item, that will result // in a "scope" array being added in the access token. foreach (var scope in ticket.GetScopes()) { identity.AddClaim(OpenIdConnectConstants.Claims.Scope, scope); } var handler = notification.SecurityTokenHandler as JwtSecurityTokenHandler; if (handler != null) { // Note: when used as an access token, a JWT token doesn't have to expose a "sub" claim // but the name identifier claim is used as a substitute when it has been explicitly added. // See https://tools.ietf.org/html/rfc7519#section-4.1.2 var subject = identity.FindFirst(JwtRegisteredClaimNames.Sub); if (subject == null) { var identifier = identity.FindFirst(ClaimTypes.NameIdentifier); if (identifier != null) { identity.AddClaim(JwtRegisteredClaimNames.Sub, identifier.Value); } } // Remove the ClaimTypes.NameIdentifier claims to avoid getting duplicate claims. // Note: the "sub" claim is automatically mapped by JwtSecurityTokenHandler // to ClaimTypes.NameIdentifier when validating a JWT token. // Note: make sure to call ToArray() to avoid an InvalidOperationException // on old versions of Mono, where FindAll() is implemented using an iterator. foreach (var claim in identity.FindAll(ClaimTypes.NameIdentifier).ToArray()) { identity.RemoveClaim(claim); } // Store the audiences as claims. foreach (var audience in ticket.GetAudiences()) { identity.AddClaim(JwtRegisteredClaimNames.Aud, audience); } // Extract the presenters from the authentication ticket. var presenters = ticket.GetPresenters().ToArray(); switch (presenters.Length) { case 0: break; case 1: identity.AddClaim(JwtRegisteredClaimNames.Azp, presenters[0]); break; default: Logger.LogWarning("Multiple presenters have been associated with the access token " + "but the JWT format only accepts single values."); // Only add the first authorized party. identity.AddClaim(JwtRegisteredClaimNames.Azp, presenters[0]); break; } var token = handler.CreateJwtSecurityToken( subject: identity, issuer: notification.Issuer, signingCredentials: notification.SigningCredentials, issuedAt: ticket.Properties.IssuedUtc.Value.UtcDateTime, notBefore: ticket.Properties.IssuedUtc.Value.UtcDateTime, expires: ticket.Properties.ExpiresUtc.Value.UtcDateTime); var x509SecurityKey = notification.SigningCredentials?.Key as X509SecurityKey; if (x509SecurityKey != null) { // Note: unlike "kid", "x5t" is not automatically added by JwtHeader's constructor in IdentityModel for .NET Core. // Though not required by the specifications, this property is needed for IdentityModel for Katana to work correctly. // See https://github.com/aspnet-contrib/AspNet.Security.OpenIdConnect.Server/issues/132 // and https://github.com/AzureAD/azure-activedirectory-identitymodel-extensions-for-dotnet/issues/181. token.Header[JwtHeaderParameterNames.X5t] = Base64UrlEncoder.Encode(x509SecurityKey.Certificate.GetCertHash()); } return(handler.WriteToken(token)); } else { var token = notification.SecurityTokenHandler.CreateToken(new SecurityTokenDescriptor { Subject = identity, Issuer = notification.Issuer, Audience = notification.Audiences.ElementAtOrDefault(0), SigningCredentials = notification.SigningCredentials, IssuedAt = notification.Ticket.Properties.IssuedUtc.Value.UtcDateTime, NotBefore = notification.Ticket.Properties.IssuedUtc.Value.UtcDateTime, Expires = notification.Ticket.Properties.ExpiresUtc.Value.UtcDateTime }); // Note: the security token is manually serialized to prevent // an exception from being thrown if the handler doesn't implement // the SecurityTokenHandler.WriteToken overload returning a string. var builder = new StringBuilder(); using (var writer = XmlWriter.Create(builder, new XmlWriterSettings { Encoding = new UTF8Encoding(false), OmitXmlDeclaration = true })) { notification.SecurityTokenHandler.WriteToken(writer, token); } return(builder.ToString()); } }
/// <summary> /// Called to create a new access token. An application may use this context /// to replace the authentication ticket before it is serialized or to use its own token format /// and skip the default logic using <see cref="BaseControlContext.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 SerializeAccessToken(SerializeAccessTokenContext context) => OnSerializeAccessToken(context);
/// <summary> /// Called to create a new access token. An application may use this context /// to replace the authentication ticket before it is serialized or to use its own token format /// and 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 SerializeAccessToken(SerializeAccessTokenContext context) => OnSerializeAccessToken(context);
private async Task <string> SerializeAccessTokenAsync( ClaimsPrincipal principal, AuthenticationProperties properties, OpenIdConnectRequest request, OpenIdConnectResponse response) { // properties.IssuedUtc and properties.ExpiresUtc // should always be preferred when explicitly set. if (properties.IssuedUtc == null) { properties.IssuedUtc = Options.SystemClock.UtcNow; } if (properties.ExpiresUtc == null) { properties.ExpiresUtc = properties.IssuedUtc + Options.AccessTokenLifetime; } // Create a new principal containing only the filtered claims. // Actors identities are also filtered (delegation scenarios). principal = principal.Clone(claim => { // Never exclude ClaimTypes.NameIdentifier. if (string.Equals(claim.Type, ClaimTypes.NameIdentifier, StringComparison.OrdinalIgnoreCase)) { return(true); } // Claims whose destination is not explicitly referenced or doesn't // contain "access_token" are not included in the access token. return(claim.HasDestination(OpenIdConnectConstants.Destinations.AccessToken)); }); var identity = (ClaimsIdentity)principal.Identity; // Create a new ticket containing the updated properties and the filtered principal. var ticket = new AuthenticationTicket(principal, properties, Options.AuthenticationScheme); ticket.SetUsage(OpenIdConnectConstants.Usages.AccessToken); ticket.SetAudiences(ticket.GetResources()); // Associate a random identifier with the access token. ticket.SetTicketId(Guid.NewGuid().ToString()); // By default, add the client_id to the list of the // presenters allowed to use the access token. if (!string.IsNullOrEmpty(request.ClientId)) { ticket.SetPresenters(request.ClientId); } var notification = new SerializeAccessTokenContext(Context, Options, request, response, ticket) { DataFormat = Options.AccessTokenFormat, Issuer = Context.GetIssuer(Options), SecurityTokenHandler = Options.AccessTokenHandler, SigningCredentials = Options.SigningCredentials.FirstOrDefault() }; await Options.Provider.SerializeAccessToken(notification); if (notification.HandledResponse || !string.IsNullOrEmpty(notification.AccessToken)) { return(notification.AccessToken); } else if (notification.Skipped) { return(null); } if (!ReferenceEquals(ticket, notification.Ticket)) { throw new InvalidOperationException("The authentication ticket cannot be replaced."); } if (!notification.Audiences.Any()) { Logger.LogInformation("No explicit audience was associated with the access token."); } if (notification.SecurityTokenHandler == null) { return(notification.DataFormat?.Protect(ticket)); } if (notification.SigningCredentials == null) { throw new InvalidOperationException("A signing key must be provided."); } // Extract the main identity from the principal. identity = (ClaimsIdentity)ticket.Principal.Identity; // Store the "unique_id" property as a claim. identity.AddClaim(OpenIdConnectConstants.Claims.JwtId, ticket.GetTicketId()); // Store the "usage" property as a claim. identity.AddClaim(OpenIdConnectConstants.Claims.Usage, ticket.GetUsage()); // Store the "confidentiality_level" property as a claim. var confidentiality = ticket.GetProperty(OpenIdConnectConstants.Properties.ConfidentialityLevel); if (!string.IsNullOrEmpty(confidentiality)) { identity.AddClaim(OpenIdConnectConstants.Claims.ConfidentialityLevel, confidentiality); } // Create a new claim per scope item, that will result // in a "scope" array being added in the access token. foreach (var scope in notification.Scopes) { identity.AddClaim(OpenIdConnectConstants.Claims.Scope, scope); } // Note: when used as an access token, a JWT token doesn't have to expose a "sub" claim // but the name identifier claim is used as a substitute when it has been explicitly added. // See https://tools.ietf.org/html/rfc7519#section-4.1.2 var subject = identity.FindFirst(OpenIdConnectConstants.Claims.Subject); if (subject == null) { var identifier = identity.FindFirst(ClaimTypes.NameIdentifier); if (identifier != null) { identity.AddClaim(OpenIdConnectConstants.Claims.Subject, identifier.Value); } } // Remove the ClaimTypes.NameIdentifier claims to avoid getting duplicate claims. // Note: the "sub" claim is automatically mapped by JwtSecurityTokenHandler // to ClaimTypes.NameIdentifier when validating a JWT token. // Note: make sure to call ToArray() to avoid an InvalidOperationException // on old versions of Mono, where FindAll() is implemented using an iterator. foreach (var claim in identity.FindAll(ClaimTypes.NameIdentifier).ToArray()) { identity.RemoveClaim(claim); } // Store the audiences as claims. foreach (var audience in notification.Audiences) { identity.AddClaim(OpenIdConnectConstants.Claims.Audience, audience); } // Extract the presenters from the authentication ticket. var presenters = notification.Presenters.ToArray(); switch (presenters.Length) { case 0: break; case 1: identity.AddClaim(OpenIdConnectConstants.Claims.AuthorizedParty, presenters[0]); break; default: Logger.LogWarning("Multiple presenters have been associated with the access token " + "but the JWT format only accepts single values."); // Only add the first authorized party. identity.AddClaim(OpenIdConnectConstants.Claims.AuthorizedParty, presenters[0]); break; } var token = notification.SecurityTokenHandler.CreateToken(new SecurityTokenDescriptor { Subject = identity, Issuer = notification.Issuer, SigningCredentials = notification.SigningCredentials, IssuedAt = notification.Ticket.Properties.IssuedUtc?.UtcDateTime, NotBefore = notification.Ticket.Properties.IssuedUtc?.UtcDateTime, Expires = notification.Ticket.Properties.ExpiresUtc?.UtcDateTime }); return(notification.SecurityTokenHandler.WriteToken(token)); }