OAUTH 2 support in the Neuron

The Neuron® now supports OAUTH 2.0, and can be used as an authorization server in OAUTH-compliant systems (from build 2026-07-13). The OAUTH 2 environment available in the Neuron includes the following resources:

• An authorization resource (RFC 6749) at /oauth/authorize.
• A token resource (RFC 6749) at /oauth/token.
• A dynamic client registration resource (RFC 7591 and RFC 7592), supporting both public and confidential client registrations, at /oauth/register.
• A management resource for dynamic client registrations (RFC 7591) at /oauth/registration.
• A resource providing support for the device authorization flow (RFC 8628) at /oauth/device
• A token introspection resource, in accordance with RFC 7662 at /oauth/introspect
• A server OAUTH meta-data resource (RFC 8414) at /.well-known/oauth-authorization-server allowing external parties a way to find available resources and features.
• A resource providing meta-data for protected resources (RFC 9728) at /.well-known/oauth-protected-resource.

Apart from the resources defined, there are some notable features and extensions that are supported, and merit mentioning:

• Proof Key for Code Exchange by OAuth Public Clients (PKCE) (RFC 7636), securing the authorization flow.
• Support for refresh tokens (RFC 6749)
• Implicit token generation from traditional Neuron authentication, or Mutual TLS (mTLS).
• OAUTH clients (services) that want to use the Neuron as an OAUTH authorization server, should register themselves with the Neuron using the dynamic client registration interface, and provide a human-readable name, logotype and corresponding URIs for more information.
• Dynamic login forms generated by the OAUTH environment are generated first in Markdown, and then transformed to HTML before being returned to the user. This allows opertors of the Neuron to customize the look & feel of the login form, by customizing the MasterOAuth.md file available in the web root folder. The dynamic form is embedded in this master file, before being rendered as HTML.

Authentication, scopes and privileges are related as follows:

• Scopes in OAUTH, are translated into Privileges in the Neuron, having the prefix OAUTH.Scope. followed by the scope, where colons (:) are replaced by periods (.).
• An external party can authenticate itself with the OAUTH environment, and be authorized to receive a JWT token, which it should provide in subsequent requests using a Bearer token in an Authorization HTTP header.
• Dynamic client registrations, and clients that authenticate themselves using credentials for an XMPP account, have no privileges by default. Attempts to authorize access to specific scopes using such accounts will be rejected.
• Administrative user accounts will have the privileges provided to them via the Roles defined for the corresponding user accounts.

Dynamic client registration has been integrated into the Neuron using the following principles:

• The Neuron enables dynamic client registration by creating an API Key with the name OAUTH. If there is no such API key on the Neuron, dynamic client registration is not permitted.
• A remote endpoint can register at most 2 clients (public or confidential).
• Registered clients receive a corresponding XMPP account with the same client_id. These accounts are disabled for XMPP communication by default, but can be enabled manually. (Future work may provide a mechanism to automatically enable such accounts, by validating e-mail and/or phone numbers provided in client registration.)

Security Note: You can limit access to OAUTH using the Web-Application Firewall (or WAF), by restricting access to any resource that starts with /oauth/.

#new, #features, #neuron, #api, #oauth, #security

HTTP Proxy

The TAG Neuron® now (from build 2026-05-12) has a new API: A generic HTTP Proxy at /HttpProxy. It allows clients to use the broker as a proxy to access resources on the Internet. This can be useful in multiple cases, for instance in environments where access to certain resources are limited, but the Neuron has free access. One such example is accessing HTTP-only resources from a smart phone environment, which requires use of HTTPS, and the remote web server does not have HTTPS enabled. (This is the case for certain ICAO Certificate Revocation Lists for example.)

Authentication

The HTTP Proxy resource requires authentication. The reason for this restriction is to avoid the broker to become a point for third parties to commit cyber-crime. The resource supports multiple form of authentication: Normal WWW-Authenticate is supported, mTLS (for brokers where this is enabled), or JWT Bearer tokens. Session login is also supported. This makes it possible to integrate the resource in web pages hosted by the Neuron.

JWT Bearer tokens is usedful in environments based on XMPP, where access to HTTP-based resources is required, but restricted by the operating system, such as the Neuro-Access smart phone app.

Since the app, in this case, has an XMPP connection to the broker, it can get a JWT token from the broker by using the HttpxClient class (HTTP over XMPP) in the Waher.Networking.XMPP.HTTPX library. Calling the GetJwtToken method returns a JWT token that can be used to make HTTP requests to the broker, authenticated as the XMPP account.

Redirecting HTTP links

If using InternetContent in the Waher.Content library to access content on the Internet, you can redirect HTTP-only links to a custom resource by providing an event handler to the WebGetter.HttpUriEventHandler event. Take the opportunity to provide a new URI in the event arguments, redirecting the request to the HTTP proxy resource of the Nueron to which the client is connected using XMPP. You also need to add the Bearer token to the Request headers available in the event arguments. The URI itself is then URI encoded and added as a sub-path to the /HttpProxy/ resource.

Example

The first step is to get a JWT token from the Neuron, identifying the XMPP connection the client has. We use the HttpxClient method GetJwtTokenAsync method, providing the number of seconds we want the token to be valid:

string Token = await this.httpxClient.GetJwtTokenAsync(60);

We then create an event handler to reroute HTTP-only requests to the HTTP proxy on the Neuron to which the client is using, using HTTPS. Creating an event handler for this purpose is simple (replacing DOMAIN in the example with the domain of the Neuron). We also need to add the Bearer JWT token by using an Authorization header:

private static void ViaProxy(object Sender, HttpUriEventArgs e)
{
	e.Uri = new Uri("https://DOMAIN/HttpProxy/" + WebUtility.UrlEncode(e.Uri.ToString()));
	e.Request.Headers.Add("Authorization", "Bearer " + Token);
}

We need to assign the event handler to the event:

WebGetter.HttpUriEventHandler += ViaProxy;

Later, when we do not need to redirect HTTP requests any longer, we need to unregister it:

WebGetter.HttpUriEventHandler -= ViaProxy;

While the event handler is registered, any access to web resources using HTTP, by using the static InternetContent class, will be seamlessly redirected to the HTTP proxy. Example:

ContentResponse Response = await InternetContent.GetAsync(
	new Uri("http://example.org/"),
	new KeyValuePair<string, string>("Accept", HtmlCodec.DefaultContentType));

#new, #features, #api, #security, #neuron

Age-verification without leaking birth date

This article describes the process of how to create a Legal Identity that can be used to demonstrate you have reached a certain age, without having to disclose your actual birth date. This is an important mechanism to protect the integrity of personal information, especially if the person is a child.

Creating a Preview ID application

The first step is to create a Preview Legal Identity application containing sufficient personal information so that the age can be verified. This application will have to contain sensitive personal information, including birth date. But creating a Preview application ensures the data is not stored in a searchable database or logs. Instead it is stored in encrypted form, and only during the process to validate the information. Once the preview application has been validated, a new application can be created, containing a subset of the sensitive information, and once that is completed, the sensitive information will be removed.

The personal data necessary to include in the Preview application is:

Property	Description
BDAY	Birth Day
BMONTH	Borth Month
BYEAR	Birth Year
AGEABOVE	Age above the stated number of years

Creating real ID application

Once the Preview application has been approved, a new, real ID application is made. This new application has to have a reference to the Preview application, and should only contain a subset of the properties. At a minimum, the following properties should be included:

Property	Description
PREVIEW	Reference to the earlier Preview application.
AGEABOVE	Age above the stated number of years

Once this application has been approved, the sensitive personal information will be removed as the preview application is deleted.

Proving your age

Proving your age is as simple as performing a Quick Login with the new identity. If property filters are used, include the AGEABOVE property. As the new identity contains a reduced set of information, and no birth-date (if it was removed in the second step above), only the AGEABOVE property is received, together with proof the Neuron has validated the claim.

How to set AGEABOVE

The AGEABOVE property should not be set to the age of the user, as that can leak personal information. Instead, it should be set to a legal limit required for one or more specific purposes. If there’s an age requirement in a country for a particular purpose, that age should be encoded in the AGEABOVE property. The property will be accepted if the personal information provided in the preview can be validated, and the age of the person deduced is at or above the indicated number.

As there are different age limits for different purposes and countries (for instance, 13, 15, 16, 17, 18, 20 and 21 are common limits), the site that tests the age of a user should not expect the number to be a specific value. Instead, it should expect the number to be at least a specific number. If there’s an age requirement for a service of 16 years of age, identities with any number for AGEABOVE greater or equal to 16 should be accepted as proof ther person is at least 16 years old.

Ensuring you have reached a certain age to create an identity

The AGEABOVE property can also be used to ensure the user of the app attempting to create an identity, has reached a certain age. Adding the property ensures the identity attempted to be created only gets approved, if the person actually has reached the age.

If the person has not reached the corresponding age, the property will become invalid, and an error with error code AgeNotReached will be logged on the application.

#new, #neuron, #features, #id, #security, #privacy

Remote Login API

Since Build 2025-12-30, extended in Build 2025-12-31, a new API called the Remote Login API is available on the TAG Neuron®. It is a complement to the Quick Login API, in the following ways:

• The Quick Login API is initiated by the client itself, for instance, by scanning a QR-code, clicking a link or logging in to a web site, for instance.

• The Remote Login API on the other hand, is initiated by a remote service, that wants to use the digital identity of the user in a second (or multi) factor authentication process (2FA, or MFA).

• The Quick Login API allows anonymous access (on the HTTP resource level), while the Remote Login API requires authorized access. This authorized access can be granted using WWW-Authenticate or Mutual TLS (mTLS). Mutual TLS is recommended, as it avoids the use of passwords. In both cases, the administrator of the Neuron providing access to the API needs to create a corresponding user and grant the user the corresponding privileges. (See the API documentation for details.)

#new, #api, #neuron, #security, #id

Web login procedure

There is a new web session login procedure available in the Neuron®. From build 2025-08-18, clients performing web session login must follow this new procedure. For users using the browser to login, this is accomplished by simply refreshing the page to ensure the most recent javascript file is loaded when logging in.

Note: Web session login is used to access the administrative page. Agent API uses another type of login, based on JWT bearer tokens.

The client calls the /Login web resource with a JSON object payload as follows:

{
	"UserName": Required(Str(PUserName)),
	"PasswordHash": Required(Str(PPasswordHash)),
	"Nonce": Required(Str(PNonce))
}

While the web resource is the same as before, the following is new:

• A PasswordHash property is sent instead of a Password in clear text (albeit over an obligatory encrypted channel, i.e. basic authentication over HTTPS). How this password hash is computed is described below.
• A Nonce value is available. This value must be unique, and cannot be reused. It is recommended this is a base64-encoding of a sufficiently large random number, for instance a 32-byte random number, to generate sufficient entropy. Reusing a nonce value will result in an error being returned.
• The respone of the web resource is another JSON object, instead of the earlier redirection response if successful, and a session variable state change, if an error occurred.

The purpose of the change is twofold:

• Secure the login endpoint
• Allow third party clients to login using the web login.

The response to the call is a JSON object as follows:

{
	"ok": Required(Bool(POk)),
	"message": Optional(Str(PMessage))
}

If ok is false, the message will contain an error message. Note that the login will be available in the current session. To enable sessions, cookies must be enabled.

Hash Digest computation

The client needs to perform the following computations to generate the hash digest to send to the Neuron®:

1. Compute H1 = SHA3-256(UserName + ":" + Domain + ":" + Password), where Domain is the host name or main domain name of the Neuron®. It cannot be an alternative domain name, it must be the main domain name of the Neuron®.

2. Compute H2 = HMAC-SHA-256(UTF8Encode(Nonce),H1), where the UTF-8 encoded Nonce is used as key to the HMAC-SHA-256 algorithm, and H1 is used as the data whose digest is to be computed. Note that the UTF-8 encoding must not include a preamble or byte-order-mark (BOM).

3. Compute PasswordHash = BASE64(H2).

Note: For a reference implementation, see the /Login.js javascript resource on an updated Neuron®.

#new, #api, #security