zoreal / oauth2

0.1.6 2026-08-27 02:56 UTC

Requires

• php: >=8.1
• ext-curl: *
• ext-json: *
• ext-openssl: *
• firebase/php-jwt: ^7.0

Requires (Dev)

• phpunit/phpunit: ^10.5 || ^11.5

MIT

Published on Packagist.org on 2026-08-27 02:56 UTC

README

Login with ZOREAL for PHP backends: the relying-party half of the flow that @zoreal/oauth2-react starts in the browser.

The browser SDK runs the pairing (QR or app link), and hands your frontend an authorization code plus the code_verifier and nonce it generated. Your frontend posts all three to your backend, and this package does the rest: the code exchange with your client authentication, ES256 verification of the ID token against the provider's JWKS, and the /userinfo read for personal claims.

zoreal/oauth2 (this package)   your backend: exchange, verify, userinfo
@zoreal/oauth2-react           your frontend: the button, the QR, the polling

Install

composer require zoreal/oauth2

PHP >= 8.1 with ext-curl, ext-json and ext-openssl. One dependency: firebase/php-jwt.

Getting your credentials

Everything the Client constructor needs comes from a ZOREAL asset.

1. Create an account at https://zoreal.com and open Assets.
2. Create an asset -- a website (a domain you own) or an app bundle (a reverse-DNS bundle id). An asset is the thing users log in to; its token is your client_id and it looks like ast_....
3. On the asset, open the OAuth2 tab and register:
   • the redirect URIs and JavaScript origins your app uses (requests from anything not registered are rejected -- this is the core control),
   • the scopes the client is allowed to request (see the catalogue below); a request for a scope you did not register is refused,
   • your client authentication: generate a client secret for client_secret_basic, or register a JWKS for private_key_jwt. A public client authenticates with PKCE alone and no secret.
4. A website asset must verify its domain (a DNS or meta-tag proof, shown in the dashboard) before it can request personal-data scopes or sign users in; the verified domain is what your users' pairwise sub is derived against.

The client_id is public -- it ships in your frontend. The client secret is a server-side secret: keep it in your secret store and never put it in the browser.

There is no test-identity sandbox -- and that is deliberate

ZOREAL never issues fake or sandbox humans: a pool of test identities would be a fraud vector against the exact thing the product proves. So you always authenticate real ZOREAL IDs.

To develop and test, create a free ZOREAL ID for yourself -- enrol in the ZOREAL ID app and sign in with it. While building, mark your asset's environment sandbox in the dashboard: a sandbox asset may register http://localhost origins and redirect URIs that a production asset may not. Flip it to production when you ship. The identities are real either way; only the allowed origins differ. There is no mock provider and no hosted test issuer to point at.

Quick start

Build one client at boot and share it; it is immutable.

use Zoreal\OAuth2\Client;
use Zoreal\OAuth2\ClientAuth;

$zoreal = new Client(
    clientId: $_ENV['ZOREAL_CLIENT_ID'],                                // ast_...
    auth: ClientAuth::clientSecretBasic($_ENV['ZOREAL_CLIENT_SECRET']),
    issuer: $_ENV['ZOREAL_ISSUER'] ?? Client::DEFAULT_ISSUER,
);

The endpoint your frontend posts to:

$login = $zoreal->authenticate(
    code: $body['code'],
    codeVerifier: $body['code_verifier'],   // PKCE is mandatory; the SDK hands it over
    nonce: $body['nonce'],                  // binds the ID token to this login
);

$login->sub();            // "TC5X-JN7G-YTSE-6E63" -- pairwise, stable for YOUR domain
$login->acr();            // "zoreal.live" | "zoreal.device" | "zoreal.session"
$login->assurance();      // uniqueness basis, verification month, chip liveness, trust tier
$login->email();          // from /userinfo, when your client has the email scope
$login->emailVerified();
$login->name();           // from /userinfo, profile.name scope

Account matching, the shape that works:

$user = $users->findByProviderUid('zoreal', $login->sub());
if ($user === null) {
    if ($login->emailVerified()) {
        $user = $users->findByEmail($login->email());   // claim, don't collide
    }
    $user ??= $users->create(['email' => $login->email()]);
    $users->linkProvider($user, 'zoreal', $login->sub());
}

Assurance levels -- acr, and requiring a liveness check

What acr is

acr is an OpenID Connect standard claim -- Authentication Context Class Reference. It is a single string in the ID token that says how strongly this particular login was authenticated. Every ZOREAL login carries one, and it is the difference between "someone who once enrolled this identity is behind this request" and "a live human, verified to be the right one, is behind this request right now".

It answers a question sub cannot. sub() tells you who -- a stable, pairwise identifier for this person at your site. acr() tells you how sure ZOREAL is that the person is really there for this login. A stolen, unlocked phone can still produce a sub; it cannot produce a fresh zoreal.live.

The three levels

Ordered weakest to strongest. Each is what actually happened, never what was requested -- a login that could only reach a weaker level says so honestly rather than claiming the level you asked for.

acr	What the holder did	amr	What it proves	What it does not prove
zoreal.session	Nothing -- a returning holder at a site they have used before, resumed silently from an existing ZOREAL session, no phone interaction	[]	Continuity: the same session ZOREAL already knew	That the holder is present, or even awake
zoreal.device	Approved the login on their enrolled phone: a signature from a key in the phone's secure element, released by a local biometric or passcode unlock	["hwk","user"]	Possession of the enrolled device and a local unlock on it	That a live face was captured for this login -- an unlocked phone in the wrong hands still signs
zoreal.live	All of the above plus a fresh face capture this login: a flash-plus-zoom video scored for presentation attacks and screen replay (moire), matched 1:1 against the government document read at enrolment	["hwk","face","user"]	A live, real, unique human, verified to be the enrolled person, at the moment of this login	-- (this is the strongest level)

amr() (Authentication Methods References) is the companion claim listing the factors used: hwk a hardware key, user a user-presence/unlock gesture, face a face biometric. zoreal.live is exactly zoreal.device with face added, because a live login is a device approval with a capture on top.

The default is zoreal.device, never zoreal.session: a login that asks for nothing still requires the enrolled phone and a local unlock. Silence has to be explicitly asked for (the SDK's prompt: 'none' path), and it succeeds only for a returning holder at a site whose consent they have already given.

When to require which

• zoreal.session -- you never require this; it is what a returning holder gets for a low-stakes convenience re-auth when they ask for the silent path.
• zoreal.device (the default) -- a forum, a community, a normal account login. Possession of the enrolled phone plus a local unlock is a high bar already; most sites want exactly this and should pass no acr at all.
• zoreal.live -- a bank onboarding, a high-value transaction, an age-gated purchase, a first login, a "confirm it is really you" step before a sensitive action. Anywhere a fresh, unforgeable proof of the live, right human is worth the few seconds a face capture costs.

Requesting versus verifying -- the one rule that matters

Requesting a level and verifying it are two separate steps, and only the second is security:

1. Request it on the wire, in the frontend, with the SDK's acr_values: 'zoreal.live'. This is what makes the holder's ZOREAL ID app run the face capture before it will approve. It is advisory -- it shapes what the holder is asked to do, nothing more. A browser is attacker-controlled; a value that only travels through it proves nothing.
2. Verify it here, at token exchange, by passing acr. The signed acr claim in the ID token -- minted by ZOREAL, not by the browser -- is the proof.

$login = $zoreal->authenticate(
    code: $body['code'],
    codeVerifier: $body['code_verifier'],
    nonce: $body['nonce'],
    acr: 'zoreal.live',   // throws VerificationError unless the signed token says so
);

$login->acr();                          // "zoreal.live" -- what actually happened
$login->live();                         // convenience: acr() === 'zoreal.live'
$login->satisfiesAcr('zoreal.device');  // true (live is stronger than device)

An RP that requests zoreal.live on the wire but never passes acr here has checked nothing -- it has only asked the holder nicely and then trusted a value it never validated.

How the check behaves

Verification satisfies upward: zoreal.session < zoreal.device < zoreal.live, so a requirement of zoreal.device accepts a zoreal.live token (the holder gave you more assurance than you demanded). A token whose acr is below the requirement, missing entirely, or outside the vocabulary is refused with VerificationError. An unknown required value -- a typo like 'zoreal.liveness' -- throws ConfigurationError instead, because that is a bug in your code, not a bad token, and failing every login silently is worse than saying so.

If you prefer to branch rather than throw, omit acr and inspect the result:

$login = $zoreal->authenticate(
    code: $body['code'],
    codeVerifier: $body['code_verifier'],
    nonce: $body['nonce'],
);
if (!$login->satisfiesAcr('zoreal.live')) {
    // step the user up, or refuse the sensitive action
}

satisfiesAcr() runs the same ordering as the enforcing check, so it agrees with what acr: 'zoreal.live' would have accepted; a value outside the vocabulary satisfies nothing.

acr versus the assurance block

Do not confuse acr with assurance(). acr grades this login event. The assurance block ($login->assurance()) describes the identity behind it -- how the person was verified at enrolment: the uniqueness basis, the verified_on month, whether chip liveness was proven, the trust_tier, and the device's key_protection. One is about now; the other is about who they are. A high-value flow usually wants both: acr: 'zoreal.live' for presence, and the assurance block for the strength of the underlying identity proofing.

What each call does

Call	What happens
authenticate($code, $codeVerifier, $nonce = null, $acr = null)	exchange + verifyIdToken, returns a Login
exchange($code, $codeVerifier)	POST {issuer}/token with your registered client authentication
verifyIdToken($jwt, $nonce = null, $acr = null)	ES256 against {issuer}/jwks, checks iss, aud, exp, nonce when given, and the acr floor when required
userinfo($accessToken)	GET {issuer}/userinfo with the Bearer token
Login::userinfo()	the above, once, memoized; [] when there is no access token

Login reads the ID token claims directly -- sub(), acr(), live(), satisfiesAcr('zoreal.device'), amr(), assurance(), ageOver(18), nationality() -- and the /userinfo claims lazily: email(), emailVerified(), name(), givenName(), familyName(), birthdate(), documentType(), documentNumber(), issuingCountry(), documentExpiresOn(), portrait().

Client authentication

Your client registers one token_endpoint_auth_method in the dashboard; build the matching ClientAuth here. The provider authenticates against what was registered, not against what arrives.

use Zoreal\OAuth2\ClientAuth;

ClientAuth::none();                                       // public client: PKCE is the only proof
ClientAuth::clientSecretBasic('zcs_...');                 // the secret travels as HTTP Basic
ClientAuth::privateKeyJwt($pemPrivateKey, kid: 'key-1');  // RFC 7523, signed here per exchange
ClientAuth::tlsClientAuth('/path/client.crt', '/path/client.key');

• none -- no secret, no key; the form carries client_id only. A public client can only ever have been granted Tier A scopes.
• client_secret_basic -- the secret rides as the HTTP Basic password, never as a form field; the form still carries client_id because the provider matches the code against it.
• private_key_jwt -- the library builds and signs a fresh assertion per exchange: iss = sub = your client id, aud = the token endpoint, exp = now + 60 seconds (the provider's maximum), a random single-use jti. Pass the key as PEM; a P-256 EC key signs ES256 (preferred -- the same key type the provider certifies), an RSA key signs RS256, anything else is refused at construction. The private key never leaves your process.
• tls_client_auth -- the certificate and key ride on the connection itself, through curl's client-certificate options. The method is registrable, and the provider currently answers the exchange with 501; that surfaces as an ExchangeError with status 501 and the provider's own words, because faking a not-yet-served method would be worse than saying so. If you inject your own transport, carrying the certificate is its job.

Scopes and claims

Scopes are requested in the frontend (the SDK's scope string, always starting with openid), consented to by the holder, and pre-authorized on your asset. What each grants and where it is delivered:

Scope	Claims	Delivered in	Tier	Requires
openid	sub, iss, aud, exp, iat, nonce, auth_time, acr, amr, and the assurance block	ID token	A	any client
zoreal.age	age_over_13/16/18/21/65 booleans -- only the thresholds you registered, never an age or birthdate	ID token	A	any client
zoreal.nationality	nationality (ISO 3166-1 alpha-3)	ID token	A	any client
email	email, email_verified	/userinfo	B	confidential client + verified domain
profile.name	name, given_name, family_name	/userinfo	B	confidential client + verified domain
profile.birthdate	birthdate (full ISO 8601 date)	/userinfo	B	confidential client + verified domain
profile.document	document_type, document_number, issuing_country, document_expires_on	/userinfo	B	confidential client + verified domain
profile.portrait	portrait (the chip's facial image; GDPR Article 9 data)	/userinfo	C	confidential client + verified domain -- registrable but not served yet

• Tier A rides in the ID token and is available to every client, so the no-backend browser button can use it. Tier B and C are personal data, served only from /userinfo to a confidential client on a domain you have verified, and never placed in a browser token.
• Age thresholds are a fixed set -- 13, 16, 18, 21, 65 -- that you register on the asset. $login->ageOver($n) returns null for a threshold you did not register (no claim was minted), which is different from false. The set is fixed on purpose: registering all five would let a site recover the age band.

Error reference

exchange() / authenticate() throw ExchangeError, which carries the provider's own $oauthError code, $description and HTTP $status verbatim. What you will actually see at /token:

$oauthError	Cause	Retryable?
invalid_grant	The code is spent -- unknown, expired (60s), already used, PKCE mismatch, or the asset's domain verification lapsed mid-flow	No. Start a new login; the code cannot be reused
invalid_request	Client authentication failed -- wrong secret, a bad private_key_jwt assertion, or tls_client_auth (not accepted at /token yet)	No. Fix your client configuration
unsupported_grant_type	Something other than authorization_code reached /token	No. A bug

A failure to reach the endpoint at all (DNS, TLS, timeout) surfaces the same way: an ExchangeError whose $oauthError is server_error. That one is transient -- a retry is reasonable where the three above are not.

Errors that surface in the frontend instead, before your backend is involved (from the SDK's onError / onNonOAuthError), so handle them there:

Where	Code	Meaning
/pair	invalid_scope	A scope not on the asset's allowed list, or a Tier B scope from a public client
/pair	invalid_request	Missing PKCE/nonce, an unverified sector, an unregistered redirect_uri, or an unknown acr_values
/pair	login_required	prompt=none with no silent session to resume -- the expected quiet outcome, not a failure
pairing	request_denied	The holder declined in their ZOREAL ID app -- not an error to alarm on; offer to try again
pairing	request_expired	The pairing window elapsed, or a required liveness the device could not meet -- offer to try again

request_denied is a person choosing not to sign in, not a fault. Treat it like a cancelled dialog: clear any spinner and offer the button again, do not log it as a failure or show a red error.

This package's own exception classes, all extending OAuth2Error so one catch can take the whole family:

Class	Means
ConfigurationError	You built the Client/ClientAuth wrong, or asked to verify an acr outside the vocabulary -- a bug in your code, not a bad token
ExchangeError	The provider refused the code exchange; carries $oauthError, $description, $status
VerificationError	The ID token did not verify -- signature, iss, aud, exp, nonce, a non-ES256 algorithm, or the acr floor. A JWKS that could not be fetched or parsed is this too, because it leaves the token unverifiable
UserinfoError	The /userinfo call failed. A returning user matched on sub can survive a caught one; a signup that needs the email cannot

OAuth2Error is the shared base; a transport failure (TransportError, internal) is caught by the Client and rethrown as the domain error of the call in flight, so you only ever handle the four above. No error message in this package ever carries a token, a secret or a key.

The assurance block

$login->assurance() is the ID token's zoreal claim -- an array describing the strength of the identity behind this login (distinct from acr, which grades the login event), or null when the token carries none. Its keys and their value sets:

Key	Values	Meaning
uniqueness	personal_number | document | none	The anchor the holder is deduplicated on. personal_number (a national number from the chip) is strongest; none means no reliable anchor
verified_on	"YYYY-MM"	The month the underlying document was verified. Quantised to a month on purpose -- a day-precision date is a cross-site correlator
chip_liveness_proven	true | false	Whether the passport chip's active-authentication challenge was proven (a genuine chip, not a clone)
trust_tier	high | standard	high when chip_liveness_proven, else standard
key_protection	secure_enclave | strongbox | tee | software	How the holder's device key is protected. software means no hardware attestation

A high-value flow usually pairs acr: 'zoreal.live' (fresh presence) with a check on the assurance block (identity strength) -- e.g. requiring uniqueness === 'personal_number' and trust_tier === 'high':

$a = $login->assurance() ?? [];
if (($a['uniqueness'] ?? null) !== 'personal_number' || ($a['trust_tier'] ?? null) !== 'high') {
    // not strong enough for this action -- refuse or step up
}

A complete example

A plain PHP login handler, end to end -- the shape a real integration takes. Adapt the $users calls to your own persistence; the ZOREAL parts are exact.

<?php
// POST /auth/zoreal
//
// Your frontend's ZorealLogin onSuccess posts { code, code_verifier, nonce }
// here over your own TLS. Protect this endpoint with your normal CSRF /
// same-origin controls, exactly as you would any login route -- the ZOREAL
// nonce protects the token, not your endpoint.

use Zoreal\OAuth2\Client;
use Zoreal\OAuth2\ClientAuth;
use Zoreal\OAuth2\ExchangeError;
use Zoreal\OAuth2\VerificationError;
use Zoreal\OAuth2\UserinfoError;

$zoreal = new Client(
    clientId: $_ENV['ZOREAL_CLIENT_ID'],
    auth: ClientAuth::clientSecretBasic($_ENV['ZOREAL_CLIENT_SECRET']),
);

$body = json_decode((string) file_get_contents('php://input'), true) ?: [];
header('Content-Type: application/json');

try {
    $login = $zoreal->authenticate(
        code: $body['code'] ?? '',
        codeVerifier: $body['code_verifier'] ?? '',
        nonce: $body['nonce'] ?? null,
        // acr: 'zoreal.live',   // add for a step-up / high-value login
    );

    $user = $users->findByProviderUid('zoreal', $login->sub());
    if ($user === null) {
        // Claim an existing account that owns this verified email rather than
        // colliding on the unique index; otherwise create one.
        if ($login->emailVerified()) {
            $user = $users->findByEmail($login->email());
        }
        $user ??= $users->create([
            'email' => $login->email(),
            'name'  => $login->name(),
        ]);
        $users->linkProvider($user, 'zoreal', $login->sub());
    }

    session_regenerate_id(true);            // fixation defence
    $_SESSION['user_id'] = $user->id;
    echo json_encode(['ok' => true]);
} catch (ExchangeError | VerificationError $e) {
    // A spent code or a token that did not verify: the login must be restarted.
    error_log('ZOREAL login failed: ' . $e->getMessage());
    http_response_code(401);
    echo json_encode(['error' => 'sign_in_failed']);
} catch (UserinfoError $e) {
    // Personal data was unreachable. Fine for a returning user matched on sub;
    // fatal for a signup that needs the email.
    http_response_code(401);
    echo json_encode(['error' => 'sign_in_failed']);
}

Things worth knowing before you integrate

• The ID token never carries personal data. sub, timing, acr/amr, the assurance block, and -- if registered -- age_over_* booleans and nationality. Email, names, birthdate and document fields come only from /userinfo, which is why authenticate alone is not enough for a signup.
• The access token lives 10 minutes. Read /userinfo while handling the login; do not store the token for later.
• sub is pairwise per verified domain. It is the right account key and it is derived from your registered sector: changing your asset's domain rotates every sub you have stored. Plan domain changes as a migration.
• ES256 only. The provider signs with nothing else, and this package refuses other algorithms -- from the header, before any signature math -- rather than negotiating.
• Always pass the nonce through, and protect your own endpoint too. The SDK generates the nonce and gives it to your frontend in onSuccess; passing it here lets the package confirm the ID token was minted for this login rather than substituted. Two things it does not do: it is not your endpoint's CSRF token (protect your /auth/zoreal route with your framework's normal CSRF / same-origin defence), and PKCE -- not the nonce -- is what proves whoever exchanges the code is whoever started the flow.
• The issuer must match the token's iss exactly -- it is compared, not normalized. Production is https://id.zoreal.com; override issuer: only when you have been given a non-production provider to point at.
• Email is a deliberate choice. It is a Tier B scope precisely because a shared email defeats the unlinkability the pairwise sub provides. Request it because you need it, not because the checkbox is familiar.
• portrait is registrable and not served yet. The provider does not return the claim today; Login::portrait() exists so your code does not change when it starts to.
• The JWKS is cached for 10 minutes and refetched once on an unknown kid, which is how a provider key rotation is absorbed without a restart. The default cache is in-process; hand the Client anything implementing the two-method CacheInterface to share it across processes.

The ZOREAL OAuth2 library family

Repository	Package	Role
zoreal-oauth2-react	@zoreal/oauth2-react (npm)	React frontend: the button, the QR, the polling
zoreal-oauth2-js	@zoreal/oauth2-js (npm)	Framework-free browser core
zoreal-oauth2-react-native	@zoreal/oauth2-react-native (npm)	React Native frontend
zoreal-oauth2-node	@zoreal/oauth2-node (npm)	Node.js backend
zoreal-oauth2-ruby	zoreal-oauth2 (RubyGems)	Ruby backend
zoreal-oauth2-python	zoreal-oauth2 (PyPI)	Python backend
zoreal-oauth2-php	zoreal/oauth2 (Packagist)	PHP backend
zoreal-oauth2-go	github.com/Bynn-Intelligence/zoreal-oauth2-go	Go backend
zoreal-oauth2-java	com.zoreal:oauth2 (Maven Central)	JVM backend
zoreal-oauth2-dotnet	Zoreal.OAuth2 (NuGet)	.NET backend

License

MIT.