Merge pull request #4955 from BookStackApp/oidc_userinfo

OIDC userinfo endpoint support

.env.example.complete

@@ -267,6 +267,7 @@ OIDC_ISSUER_DISCOVER=false
 OIDC_PUBLIC_KEY=null
 OIDC_AUTH_ENDPOINT=null
 OIDC_TOKEN_ENDPOINT=null
+OIDC_USERINFO_ENDPOINT=null
 OIDC_ADDITIONAL_SCOPES=null
 OIDC_DUMP_USER_DETAILS=false
 OIDC_USER_TO_GROUPS=false

app/Access/Oidc/OidcIdToken.php

@@ -2,58 +2,8 @@
 
 namespace BookStack\Access\Oidc;
 
-class OidcIdToken
+class OidcIdToken extends OidcJwtWithClaims implements ProvidesClaims
 {
-    protected array $header;
-    protected array $payload;
-    protected string $signature;
-    protected string $issuer;
-    protected array $tokenParts = [];
-
-    /**
-     * @var array[]|string[]
-     */
-    protected array $keys;
-
-    public function __construct(string $token, string $issuer, array $keys)
-    {
-        $this->keys = $keys;
-        $this->issuer = $issuer;
-        $this->parse($token);
-    }
-
-    /**
-     * Parse the token content into its components.
-     */
-    protected function parse(string $token): void
-    {
-        $this->tokenParts = explode('.', $token);
-        $this->header = $this->parseEncodedTokenPart($this->tokenParts[0]);
-        $this->payload = $this->parseEncodedTokenPart($this->tokenParts[1] ?? '');
-        $this->signature = $this->base64UrlDecode($this->tokenParts[2] ?? '') ?: '';
-    }
-
-    /**
-     * Parse a Base64-JSON encoded token part.
-     * Returns the data as a key-value array or empty array upon error.
-     */
-    protected function parseEncodedTokenPart(string $part): array
-    {
-        $json = $this->base64UrlDecode($part) ?: '{}';
-        $decoded = json_decode($json, true);
-
-        return is_array($decoded) ? $decoded : [];
-    }
-
-    /**
-     * Base64URL decode. Needs some character conversions to be compatible
-     * with PHP's default base64 handling.
-     */
-    protected function base64UrlDecode(string $encoded): string
-    {
-        return base64_decode(strtr($encoded, '-_', '+/'));
-    }
-
     /**
      * Validate all possible parts of the id token.
      *
@@ -61,91 +11,12 @@ class OidcIdToken
      */
     public function validate(string $clientId): bool
     {
-        $this->validateTokenStructure();
+        parent::validateCommonTokenDetails($clientId);
-        $this->validateTokenSignature();
         $this->validateTokenClaims($clientId);
 
         return true;
     }
 
-    /**
-     * Fetch a specific claim from this token.
-     * Returns null if it is null or does not exist.
-     *
-     * @return mixed|null
-     */
-    public function getClaim(string $claim)
-    {
-        return $this->payload[$claim] ?? null;
-    }
-
-    /**
-     * Get all returned claims within the token.
-     */
-    public function getAllClaims(): array
-    {
-        return $this->payload;
-    }
-
-    /**
-     * Replace the existing claim data of this token with that provided.
-     */
-    public function replaceClaims(array $claims): void
-    {
-        $this->payload = $claims;
-    }
-
-    /**
-     * Validate the structure of the given token and ensure we have the required pieces.
-     * As per https://datatracker.ietf.org/doc/html/rfc7519#section-7.2.
-     *
-     * @throws OidcInvalidTokenException
-     */
-    protected function validateTokenStructure(): void
-    {
-        foreach (['header', 'payload'] as $prop) {
-            if (empty($this->$prop) || !is_array($this->$prop)) {
-                throw new OidcInvalidTokenException("Could not parse out a valid {$prop} within the provided token");
-            }
-        }
-
-        if (empty($this->signature) || !is_string($this->signature)) {
-            throw new OidcInvalidTokenException('Could not parse out a valid signature within the provided token');
-        }
-    }
-
-    /**
-     * Validate the signature of the given token and ensure it validates against the provided key.
-     *
-     * @throws OidcInvalidTokenException
-     */
-    protected function validateTokenSignature(): void
-    {
-        if ($this->header['alg'] !== 'RS256') {
-            throw new OidcInvalidTokenException("Only RS256 signature validation is supported. Token reports using {$this->header['alg']}");
-        }
-
-        $parsedKeys = array_map(function ($key) {
-            try {
-                return new OidcJwtSigningKey($key);
-            } catch (OidcInvalidKeyException $e) {
-                throw new OidcInvalidTokenException('Failed to read signing key with error: ' . $e->getMessage());
-            }
-        }, $this->keys);
-
-        $parsedKeys = array_filter($parsedKeys);
-
-        $contentToSign = $this->tokenParts[0] . '.' . $this->tokenParts[1];
-        /** @var OidcJwtSigningKey $parsedKey */
-        foreach ($parsedKeys as $parsedKey) {
-            if ($parsedKey->verify($contentToSign, $this->signature)) {
-                return;
-            }
-        }
-
-        throw new OidcInvalidTokenException('Token signature could not be validated using the provided keys');
-    }
-
     /**
      * Validate the claims of the token.
      * As per https://openid.net/specs/openid-connect-basic-1_0.html#IDTokenValidation.
@@ -156,27 +27,18 @@ class OidcIdToken
     {
         // 1. The Issuer Identifier for the OpenID Provider (which is typically obtained during Discovery)
         // MUST exactly match the value of the iss (issuer) Claim.
-        if (empty($this->payload['iss']) || $this->issuer !== $this->payload['iss']) {
+        // Already done in parent.
-            throw new OidcInvalidTokenException('Missing or non-matching token issuer value');
-        }
 
         // 2. The Client MUST validate that the aud (audience) Claim contains its client_id value registered
         // at the Issuer identified by the iss (issuer) Claim as an audience. The ID Token MUST be rejected
         // if the ID Token does not list the Client as a valid audience, or if it contains additional
         // audiences not trusted by the Client.
-        if (empty($this->payload['aud'])) {
+        // Partially done in parent.
-            throw new OidcInvalidTokenException('Missing token audience value');
-        }
-
         $aud = is_string($this->payload['aud']) ? [$this->payload['aud']] : $this->payload['aud'];
         if (count($aud) !== 1) {
             throw new OidcInvalidTokenException('Token audience value has ' . count($aud) . ' values, Expected 1');
         }
 
-        if ($aud[0] !== $clientId) {
-            throw new OidcInvalidTokenException('Token audience value did not match the expected client_id');
-        }
-
         // 3. If the ID Token contains multiple audiences, the Client SHOULD verify that an azp Claim is present.
         // NOTE: Addressed by enforcing a count of 1 above.
 

app/Access/Oidc/OidcJwtWithClaims.php

@@ -0,0 +1,174 @@
+<?php
+
+namespace BookStack\Access\Oidc;
+
+class OidcJwtWithClaims implements ProvidesClaims
+{
+    protected array $header;
+    protected array $payload;
+    protected string $signature;
+    protected string $issuer;
+    protected array $tokenParts = [];
+
+    /**
+     * @var array[]|string[]
+     */
+    protected array $keys;
+
+    public function __construct(string $token, string $issuer, array $keys)
+    {
+        $this->keys = $keys;
+        $this->issuer = $issuer;
+        $this->parse($token);
+    }
+
+    /**
+     * Parse the token content into its components.
+     */
+    protected function parse(string $token): void
+    {
+        $this->tokenParts = explode('.', $token);
+        $this->header = $this->parseEncodedTokenPart($this->tokenParts[0]);
+        $this->payload = $this->parseEncodedTokenPart($this->tokenParts[1] ?? '');
+        $this->signature = $this->base64UrlDecode($this->tokenParts[2] ?? '') ?: '';
+    }
+
+    /**
+     * Parse a Base64-JSON encoded token part.
+     * Returns the data as a key-value array or empty array upon error.
+     */
+    protected function parseEncodedTokenPart(string $part): array
+    {
+        $json = $this->base64UrlDecode($part) ?: '{}';
+        $decoded = json_decode($json, true);
+
+        return is_array($decoded) ? $decoded : [];
+    }
+
+    /**
+     * Base64URL decode. Needs some character conversions to be compatible
+     * with PHP's default base64 handling.
+     */
+    protected function base64UrlDecode(string $encoded): string
+    {
+        return base64_decode(strtr($encoded, '-_', '+/'));
+    }
+
+    /**
+     * Validate common parts of OIDC JWT tokens.
+     *
+     * @throws OidcInvalidTokenException
+     */
+    public function validateCommonTokenDetails(string $clientId): bool
+    {
+        $this->validateTokenStructure();
+        $this->validateTokenSignature();
+        $this->validateCommonClaims($clientId);
+
+        return true;
+    }
+
+    /**
+     * Fetch a specific claim from this token.
+     * Returns null if it is null or does not exist.
+     */
+    public function getClaim(string $claim): mixed
+    {
+        return $this->payload[$claim] ?? null;
+    }
+
+    /**
+     * Get all returned claims within the token.
+     */
+    public function getAllClaims(): array
+    {
+        return $this->payload;
+    }
+
+    /**
+     * Replace the existing claim data of this token with that provided.
+     */
+    public function replaceClaims(array $claims): void
+    {
+        $this->payload = $claims;
+    }
+
+    /**
+     * Validate the structure of the given token and ensure we have the required pieces.
+     * As per https://datatracker.ietf.org/doc/html/rfc7519#section-7.2.
+     *
+     * @throws OidcInvalidTokenException
+     */
+    protected function validateTokenStructure(): void
+    {
+        foreach (['header', 'payload'] as $prop) {
+            if (empty($this->$prop) || !is_array($this->$prop)) {
+                throw new OidcInvalidTokenException("Could not parse out a valid {$prop} within the provided token");
+            }
+        }
+
+        if (empty($this->signature) || !is_string($this->signature)) {
+            throw new OidcInvalidTokenException('Could not parse out a valid signature within the provided token');
+        }
+    }
+
+    /**
+     * Validate the signature of the given token and ensure it validates against the provided key.
+     *
+     * @throws OidcInvalidTokenException
+     */
+    protected function validateTokenSignature(): void
+    {
+        if ($this->header['alg'] !== 'RS256') {
+            throw new OidcInvalidTokenException("Only RS256 signature validation is supported. Token reports using {$this->header['alg']}");
+        }
+
+        $parsedKeys = array_map(function ($key) {
+            try {
+                return new OidcJwtSigningKey($key);
+            } catch (OidcInvalidKeyException $e) {
+                throw new OidcInvalidTokenException('Failed to read signing key with error: ' . $e->getMessage());
+            }
+        }, $this->keys);
+
+        $parsedKeys = array_filter($parsedKeys);
+
+        $contentToSign = $this->tokenParts[0] . '.' . $this->tokenParts[1];
+        /** @var OidcJwtSigningKey $parsedKey */
+        foreach ($parsedKeys as $parsedKey) {
+            if ($parsedKey->verify($contentToSign, $this->signature)) {
+                return;
+            }
+        }
+
+        throw new OidcInvalidTokenException('Token signature could not be validated using the provided keys');
+    }
+
+    /**
+     * Validate common claims for OIDC JWT tokens.
+     * As per https://openid.net/specs/openid-connect-basic-1_0.html#IDTokenValidation
+     * and https://openid.net/specs/openid-connect-core-1_0.html#UserInfoResponse
+     *
+     * @throws OidcInvalidTokenException
+     */
+    protected function validateCommonClaims(string $clientId): void
+    {
+        // 1. The Issuer Identifier for the OpenID Provider (which is typically obtained during Discovery)
+        // MUST exactly match the value of the iss (issuer) Claim.
+        if (empty($this->payload['iss']) || $this->issuer !== $this->payload['iss']) {
+            throw new OidcInvalidTokenException('Missing or non-matching token issuer value');
+        }
+
+        // 2. The Client MUST validate that the aud (audience) Claim contains its client_id value registered
+        // at the Issuer identified by the iss (issuer) Claim as an audience. The ID Token MUST be rejected
+        // if the ID Token does not list the Client as a valid audience.
+        if (empty($this->payload['aud'])) {
+            throw new OidcInvalidTokenException('Missing token audience value');
+        }
+
+        $aud = is_string($this->payload['aud']) ? [$this->payload['aud']] : $this->payload['aud'];
+        if (!in_array($clientId, $aud, true)) {
+            throw new OidcInvalidTokenException('Token audience value did not match the expected client_id');
+        }
+    }
+}

app/Access/Oidc/OidcProviderSettings.php

@@ -18,10 +18,10 @@ class OidcProviderSettings
     public string $issuer;
     public string $clientId;
     public string $clientSecret;
-    public ?string $redirectUri;
     public ?string $authorizationEndpoint;
     public ?string $tokenEndpoint;
     public ?string $endSessionEndpoint;
+    public ?string $userinfoEndpoint;
 
     /**
      * @var string[]|array[]
@@ -37,7 +37,7 @@ class OidcProviderSettings
     /**
      * Apply an array of settings to populate setting properties within this class.
      */
-    protected function applySettingsFromArray(array $settingsArray)
+    protected function applySettingsFromArray(array $settingsArray): void
     {
         foreach ($settingsArray as $key => $value) {
             if (property_exists($this, $key)) {
@@ -51,9 +51,9 @@ class OidcProviderSettings
      *
      * @throws InvalidArgumentException
      */
-    protected function validateInitial()
+    protected function validateInitial(): void
     {
-        $required = ['clientId', 'clientSecret', 'redirectUri', 'issuer'];
+        $required = ['clientId', 'clientSecret', 'issuer'];
         foreach ($required as $prop) {
             if (empty($this->$prop)) {
                 throw new InvalidArgumentException("Missing required configuration \"{$prop}\" value");
@@ -73,12 +73,20 @@ class OidcProviderSettings
     public function validate(): void
     {
         $this->validateInitial();
+
         $required = ['keys', 'tokenEndpoint', 'authorizationEndpoint'];
         foreach ($required as $prop) {
             if (empty($this->$prop)) {
                 throw new InvalidArgumentException("Missing required configuration \"{$prop}\" value");
             }
         }
+
+        $endpointProperties = ['tokenEndpoint', 'authorizationEndpoint', 'userinfoEndpoint'];
+        foreach ($endpointProperties as $prop) {
+            if (is_string($this->$prop) && !str_starts_with($this->$prop, 'https://')) {
+                throw new InvalidArgumentException("Endpoint value for \"{$prop}\" must start with https://");
+            }
+        }
     }
 
     /**
@@ -86,7 +94,7 @@ class OidcProviderSettings
      *
      * @throws OidcIssuerDiscoveryException
      */
-    public function discoverFromIssuer(ClientInterface $httpClient, Repository $cache, int $cacheMinutes)
+    public function discoverFromIssuer(ClientInterface $httpClient, Repository $cache, int $cacheMinutes): void
     {
         try {
             $cacheKey = 'oidc-discovery::' . $this->issuer;
@@ -128,6 +136,10 @@ class OidcProviderSettings
             $discoveredSettings['tokenEndpoint'] = $result['token_endpoint'];
         }
 
+        if (!empty($result['userinfo_endpoint'])) {
+            $discoveredSettings['userinfoEndpoint'] = $result['userinfo_endpoint'];
+        }
+
         if (!empty($result['jwks_uri'])) {
             $keys = $this->loadKeysFromUri($result['jwks_uri'], $httpClient);
             $discoveredSettings['keys'] = $this->filterKeys($keys);
@@ -175,9 +187,9 @@ class OidcProviderSettings
     /**
      * Get the settings needed by an OAuth provider, as a key=>value array.
      */
-    public function arrayForProvider(): array
+    public function arrayForOAuthProvider(): array
     {
-        $settingKeys = ['clientId', 'clientSecret', 'redirectUri', 'authorizationEndpoint', 'tokenEndpoint'];
+        $settingKeys = ['clientId', 'clientSecret', 'authorizationEndpoint', 'tokenEndpoint', 'userinfoEndpoint'];
         $settings = [];
         foreach ($settingKeys as $setting) {
             $settings[$setting] = $this->$setting;

app/Access/Oidc/OidcService.php

@@ -12,7 +12,6 @@ use BookStack\Facades\Theme;
 use BookStack\Http\HttpRequestService;
 use BookStack\Theming\ThemeEvents;
 use BookStack\Users\Models\User;
-use Illuminate\Support\Arr;
 use Illuminate\Support\Facades\Cache;
 use League\OAuth2\Client\OptionProvider\HttpBasicAuthOptionProvider;
 use League\OAuth2\Client\Provider\Exception\IdentityProviderException;
@@ -91,10 +90,10 @@ class OidcService
             'issuer'                => $config['issuer'],
             'clientId'              => $config['client_id'],
             'clientSecret'          => $config['client_secret'],
-            'redirectUri'           => url('/oidc/callback'),
             'authorizationEndpoint' => $config['authorization_endpoint'],
             'tokenEndpoint'         => $config['token_endpoint'],
             'endSessionEndpoint'    => is_string($config['end_session_endpoint']) ? $config['end_session_endpoint'] : null,
+            'userinfoEndpoint'      => $config['userinfo_endpoint'],
         ]);
 
         // Use keys if configured
@@ -129,7 +128,10 @@ class OidcService
      */
     protected function getProvider(OidcProviderSettings $settings): OidcOAuthProvider
     {
-        $provider = new OidcOAuthProvider($settings->arrayForProvider(), [
+        $provider = new OidcOAuthProvider([
+            ...$settings->arrayForOAuthProvider(),
+            'redirectUri' => url('/oidc/callback'),
+        ], [
             'httpClient'     => $this->http->buildClient(5),
             'optionProvider' => new HttpBasicAuthOptionProvider(),
         ]);
@@ -156,69 +158,6 @@ class OidcService
         return array_filter($scopeArr);
     }
 
-    /**
-     * Calculate the display name.
-     */
-    protected function getUserDisplayName(OidcIdToken $token, string $defaultValue): string
-    {
-        $displayNameAttrString = $this->config()['display_name_claims'] ?? '';
-        $displayNameAttrs = explode('|', $displayNameAttrString);
-
-        $displayName = [];
-        foreach ($displayNameAttrs as $dnAttr) {
-            $dnComponent = $token->getClaim($dnAttr) ?? '';
-            if ($dnComponent !== '') {
-                $displayName[] = $dnComponent;
-            }
-        }
-
-        if (count($displayName) == 0) {
-            $displayName[] = $defaultValue;
-        }
-
-        return implode(' ', $displayName);
-    }
-
-    /**
-     * Extract the assigned groups from the id token.
-     *
-     * @return string[]
-     */
-    protected function getUserGroups(OidcIdToken $token): array
-    {
-        $groupsAttr = $this->config()['groups_claim'];
-        if (empty($groupsAttr)) {
-            return [];
-        }
-
-        $groupsList = Arr::get($token->getAllClaims(), $groupsAttr);
-        if (!is_array($groupsList)) {
-            return [];
-        }
-
-        return array_values(array_filter($groupsList, function ($val) {
-            return is_string($val);
-        }));
-    }
-
-    /**
-     * Extract the details of a user from an ID token.
-     *
-     * @return array{name: string, email: string, external_id: string, groups: string[]}
-     */
-    protected function getUserDetails(OidcIdToken $token): array
-    {
-        $idClaim = $this->config()['external_id_claim'];
-        $id = $token->getClaim($idClaim);
-
-        return [
-            'external_id' => $id,
-            'email'       => $token->getClaim('email'),
-            'name'        => $this->getUserDisplayName($token, $id),
-            'groups'      => $this->getUserGroups($token),
-        ];
-    }
-
     /**
      * Processes a received access token for a user. Login the user when
      * they exist, optionally registering them automatically.
@@ -255,34 +194,35 @@ class OidcService
         try {
             $idToken->validate($settings->clientId);
         } catch (OidcInvalidTokenException $exception) {
-            throw new OidcException("ID token validate failed with error: {$exception->getMessage()}");
+            throw new OidcException("ID token validation failed with error: {$exception->getMessage()}");
         }
 
-        $userDetails = $this->getUserDetails($idToken);
+        $userDetails = $this->getUserDetailsFromToken($idToken, $accessToken, $settings);
-        $isLoggedIn = auth()->check();
+        if (empty($userDetails->email)) {
-
-        if (empty($userDetails['email'])) {
             throw new OidcException(trans('errors.oidc_no_email_address'));
         }
+        if (empty($userDetails->name)) {
+            $userDetails->name = $userDetails->externalId;
+        }
 
+        $isLoggedIn = auth()->check();
         if ($isLoggedIn) {
             throw new OidcException(trans('errors.oidc_already_logged_in'));
         }
 
         try {
             $user = $this->registrationService->findOrRegister(
-                $userDetails['name'],
+                $userDetails->name,
-                $userDetails['email'],
+                $userDetails->email,
-                $userDetails['external_id']
+                $userDetails->externalId
             );
         } catch (UserRegistrationException $exception) {
             throw new OidcException($exception->getMessage());
         }
 
         if ($this->shouldSyncGroups()) {
-            $groups = $userDetails['groups'];
             $detachExisting = $this->config()['remove_from_groups'];
-            $this->groupService->syncUserWithFoundGroups($user, $groups, $detachExisting);
+            $this->groupService->syncUserWithFoundGroups($user, $userDetails->groups ?? [], $detachExisting);
         }
 
         $this->loginService->login($user, 'oidc');
@@ -290,6 +230,45 @@ class OidcService
         return $user;
     }
 
+    /**
+     * @throws OidcException
+     */
+    protected function getUserDetailsFromToken(OidcIdToken $idToken, OidcAccessToken $accessToken, OidcProviderSettings $settings): OidcUserDetails
+    {
+        $userDetails = new OidcUserDetails();
+        $userDetails->populate(
+            $idToken,
+            $this->config()['external_id_claim'],
+            $this->config()['display_name_claims'] ?? '',
+            $this->config()['groups_claim'] ?? ''
+        );
+
+        if (!$userDetails->isFullyPopulated($this->shouldSyncGroups()) && !empty($settings->userinfoEndpoint)) {
+            $provider = $this->getProvider($settings);
+            $request = $provider->getAuthenticatedRequest('GET', $settings->userinfoEndpoint, $accessToken->getToken());
+            $response = new OidcUserinfoResponse(
+                $provider->getResponse($request),
+                $settings->issuer,
+                $settings->keys,
+            );
+
+            try {
+                $response->validate($idToken->getClaim('sub'), $settings->clientId);
+            } catch (OidcInvalidTokenException $exception) {
+                throw new OidcException("Userinfo endpoint response validation failed with error: {$exception->getMessage()}");
+            }
+
+            $userDetails->populate(
+                $response,
+                $this->config()['external_id_claim'],
+                $this->config()['display_name_claims'] ?? '',
+                $this->config()['groups_claim'] ?? ''
+            );
+        }
+
+        return $userDetails;
+    }
+
     /**
      * Get the OIDC config from the application.
      */

app/Access/Oidc/OidcUserDetails.php

@@ -0,0 +1,75 @@
+<?php
+
+namespace BookStack\Access\Oidc;
+
+use Illuminate\Support\Arr;
+
+class OidcUserDetails
+{
+    public function __construct(
+        public ?string $externalId = null,
+        public ?string $email = null,
+        public ?string $name = null,
+        public ?array $groups = null,
+    ) {
+    }
+
+    /**
+     * Check if the user details are fully populated for our usage.
+     */
+    public function isFullyPopulated(bool $groupSyncActive): bool
+    {
+        $hasEmpty = empty($this->externalId)
+            || empty($this->email)
+            || empty($this->name)
+            || ($groupSyncActive && empty($this->groups));
+
+        return !$hasEmpty;
+    }
+
+    /**
+     * Populate user details from the given claim data.
+     */
+    public function populate(
+        ProvidesClaims $claims,
+        string $idClaim,
+        string $displayNameClaims,
+        string $groupsClaim,
+    ): void {
+        $this->externalId = $claims->getClaim($idClaim) ?? $this->externalId;
+        $this->email = $claims->getClaim('email') ?? $this->email;
+        $this->name = static::getUserDisplayName($displayNameClaims, $claims) ?? $this->name;
+        $this->groups = static::getUserGroups($groupsClaim, $claims) ?? $this->groups;
+    }
+
+    protected static function getUserDisplayName(string $displayNameClaims, ProvidesClaims $token): string
+    {
+        $displayNameClaimParts = explode('|', $displayNameClaims);
+
+        $displayName = [];
+        foreach ($displayNameClaimParts as $claim) {
+            $component = $token->getClaim(trim($claim)) ?? '';
+            if ($component !== '') {
+                $displayName[] = $component;
+            }
+        }
+
+        return implode(' ', $displayName);
+    }
+
+    protected static function getUserGroups(string $groupsClaim, ProvidesClaims $token): array
+    {
+        if (empty($groupsClaim)) {
+            return [];
+        }
+
+        $groupsList = Arr::get($token->getAllClaims(), $groupsClaim);
+        if (!is_array($groupsList)) {
+            return [];
+        }
+
+        return array_values(array_filter($groupsList, function ($val) {
+            return is_string($val);
+        }));
+    }
+}

app/Access/Oidc/OidcUserinfoResponse.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace BookStack\Access\Oidc;
+
+use Psr\Http\Message\ResponseInterface;
+
+class OidcUserinfoResponse implements ProvidesClaims
+{
+    protected array $claims = [];
+    protected ?OidcJwtWithClaims $jwt = null;
+
+    public function __construct(ResponseInterface $response, string $issuer, array $keys)
+    {
+        $contentType = $response->getHeader('Content-Type')[0];
+        if ($contentType === 'application/json') {
+            $this->claims = json_decode($response->getBody()->getContents(), true);
+        }
+
+        if ($contentType === 'application/jwt') {
+            $this->jwt = new OidcJwtWithClaims($response->getBody()->getContents(), $issuer, $keys);
+            $this->claims = $this->jwt->getAllClaims();
+        }
+    }
+
+    /**
+     * @throws OidcInvalidTokenException
+     */
+    public function validate(string $idTokenSub, string $clientId): bool
+    {
+        if (!is_null($this->jwt)) {
+            $this->jwt->validateCommonTokenDetails($clientId);
+        }
+
+        $sub = $this->getClaim('sub');
+
+        // Spec: v1.0 5.3.2: The sub (subject) Claim MUST always be returned in the UserInfo Response.
+        if (!is_string($sub) || empty($sub)) {
+            throw new OidcInvalidTokenException("No valid subject value found in userinfo data");
+        }
+
+        // Spec: v1.0 5.3.2: The sub Claim in the UserInfo Response MUST be verified to exactly match the sub Claim in the ID Token;
+        // if they do not match, the UserInfo Response values MUST NOT be used.
+        if ($idTokenSub !== $sub) {
+            throw new OidcInvalidTokenException("Subject value provided in the userinfo endpoint does not match the provided ID token value");
+        }
+
+        // Spec v1.0 5.3.4 Defines the following:
+        // Verify that the OP that responded was the intended OP through a TLS server certificate check, per RFC 6125 [RFC6125].
+          // This is effectively done as part of the HTTP request we're making through CURLOPT_SSL_VERIFYHOST on the request.
+        // If the Client has provided a userinfo_encrypted_response_alg parameter during Registration, decrypt the UserInfo Response using the keys specified during Registration.
+          // We don't currently support JWT encryption for OIDC
+        // If the response was signed, the Client SHOULD validate the signature according to JWS [JWS].
+          // This is done as part of the validateCommonClaims above.
+
+        return true;
+    }
+
+    public function getClaim(string $claim): mixed
+    {
+        return $this->claims[$claim] ?? null;
+    }
+
+    public function getAllClaims(): array
+    {
+        return $this->claims;
+    }
+}

app/Access/Oidc/ProvidesClaims.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace BookStack\Access\Oidc;
+
+interface ProvidesClaims
+{
+    /**
+     * Fetch a specific claim.
+     * Returns null if it is null or does not exist.
+     */
+    public function getClaim(string $claim): mixed;
+
+    /**
+     * Get all contained claims.
+     */
+    public function getAllClaims(): array;
+}

app/Config/oidc.php

@@ -35,6 +35,7 @@ return [
     // OAuth2 endpoints.
     'authorization_endpoint' => env('OIDC_AUTH_ENDPOINT', null),
     'token_endpoint'         => env('OIDC_TOKEN_ENDPOINT', null),
+    'userinfo_endpoint'      => env('OIDC_USERINFO_ENDPOINT', null),
 
     // OIDC RP-Initiated Logout endpoint URL.
     // A false value force-disables RP-Initiated Logout.

tests/Auth/OidcTest.php

@@ -37,6 +37,7 @@ class OidcTest extends TestCase
             'oidc.issuer'                 => OidcJwtHelper::defaultIssuer(),
             'oidc.authorization_endpoint' => 'https://oidc.local/auth',
             'oidc.token_endpoint'         => 'https://oidc.local/token',
+            'oidc.userinfo_endpoint'      => 'https://oidc.local/userinfo',
             'oidc.discover'               => false,
             'oidc.dump_user_details'      => false,
             'oidc.additional_scopes'      => '',
@@ -208,6 +209,8 @@ class OidcTest extends TestCase
 
     public function test_auth_fails_if_no_email_exists_in_user_data()
     {
+        config()->set('oidc.userinfo_endpoint', null);
+
         $this->runLogin([
             'email' => '',
             'sub'   => 'benny505',
@@ -270,10 +273,38 @@ class OidcTest extends TestCase
         ]);
         $resp = $this->followRedirects($resp);
 
-        $resp->assertSeeText('ID token validate failed with error: Missing token subject value');
+        $resp->assertSeeText('ID token validation failed with error: Missing token subject value');
         $this->assertFalse(auth()->check());
     }
 
+    public function test_auth_fails_if_endpoints_start_with_https()
+    {
+        $endpointConfigKeys = [
+            'oidc.token_endpoint' => 'tokenEndpoint',
+            'oidc.authorization_endpoint' => 'authorizationEndpoint',
+            'oidc.userinfo_endpoint' => 'userinfoEndpoint',
+        ];
+
+        foreach ($endpointConfigKeys as $endpointConfigKey => $endpointName) {
+            $logger = $this->withTestLogger();
+            $original = config()->get($endpointConfigKey);
+            $new = str_replace('https://', 'http://', $original);
+            config()->set($endpointConfigKey, $new);
+
+            $this->withoutExceptionHandling();
+            $err = null;
+            try {
+                $resp = $this->runLogin();
+                $resp->assertRedirect('/login');
+            } catch (\Exception $exception) {
+                $err = $exception;
+            }
+            $this->assertEquals("Endpoint value for \"{$endpointName}\" must start with https://", $err->getMessage());
+
+            config()->set($endpointConfigKey, $original);
+        }
+    }
+
     public function test_auth_login_with_autodiscovery()
     {
         $this->withAutodiscovery();
@@ -689,22 +720,152 @@ class OidcTest extends TestCase
         $this->assertEquals($pkceCode, $bodyParams['code_verifier']);
     }
 
-    protected function withAutodiscovery()
+    public function test_userinfo_endpoint_used_if_missing_claims_in_id_token()
+    {
+        config()->set('oidc.display_name_claims', 'first_name|last_name');
+        $this->post('/oidc/login');
+        $state = session()->get('oidc_state');
+
+        $client = $this->mockHttpClient([
+            $this->getMockAuthorizationResponse(['name' => null]),
+            new Response(200, [
+                'Content-Type'  => 'application/json',
+            ], json_encode([
+                'sub' => OidcJwtHelper::defaultPayload()['sub'],
+                'first_name' => 'Barry',
+                'last_name' => 'Userinfo',
+            ]))
+        ]);
+
+        $resp = $this->get('/oidc/callback?code=SplxlOBeZQQYbYS6WxSbIA&state=' . $state);
+        $resp->assertRedirect('/');
+        $this->assertEquals(2, $client->requestCount());
+
+        $userinfoRequest = $client->requestAt(1);
+        $this->assertEquals('GET', $userinfoRequest->getMethod());
+        $this->assertEquals('https://oidc.local/userinfo', (string) $userinfoRequest->getUri());
+
+        $this->assertEquals('Barry Userinfo', user()->name);
+    }
+
+    public function test_userinfo_endpoint_fetch_with_different_sub_throws_error()
+    {
+        $userinfoResponseData = ['sub' => 'dcba4321'];
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/json'], json_encode($userinfoResponseData));
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: Subject value provided in the userinfo endpoint does not match the provided ID token value');
+    }
+
+    public function test_userinfo_endpoint_fetch_returning_no_sub_throws_error()
+    {
+        $userinfoResponseData = ['name' => 'testing'];
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/json'], json_encode($userinfoResponseData));
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: No valid subject value found in userinfo data');
+    }
+
+    public function test_userinfo_endpoint_fetch_can_parsed_nested_groups()
+    {
+        config()->set([
+            'oidc.user_to_groups'     => true,
+            'oidc.groups_claim'       => 'my.nested.groups.attr',
+            'oidc.remove_from_groups' => false,
+        ]);
+
+        $roleA = Role::factory()->create(['display_name' => 'Ducks']);
+        $userinfoResponseData = [
+            'sub' => OidcJwtHelper::defaultPayload()['sub'],
+            'my' => ['nested' => ['groups' => ['attr' => ['Ducks', 'Donkeys']]]]
+        ];
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/json'], json_encode($userinfoResponseData));
+        $resp = $this->runLogin(['groups' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/');
+
+        $user = User::where('email', OidcJwtHelper::defaultPayload()['email'])->first();
+        $this->assertTrue($user->hasRole($roleA->id));
+    }
+
+    public function test_userinfo_endpoint_jwks_response_handled()
+    {
+        $userinfoResponseData = OidcJwtHelper::idToken(['name' => 'Barry Jwks']);
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/jwt'], $userinfoResponseData);
+
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/');
+
+        $user = User::where('email', OidcJwtHelper::defaultPayload()['email'])->first();
+        $this->assertEquals('Barry Jwks', $user->name);
+    }
+
+    public function test_userinfo_endpoint_jwks_response_returning_no_sub_throws()
+    {
+        $userinfoResponseData = OidcJwtHelper::idToken(['sub' => null]);
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/jwt'], $userinfoResponseData);
+
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: No valid subject value found in userinfo data');
+    }
+
+    public function test_userinfo_endpoint_jwks_response_returning_non_matching_sub_throws()
+    {
+        $userinfoResponseData = OidcJwtHelper::idToken(['sub' => 'zzz123']);
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/jwt'], $userinfoResponseData);
+
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: Subject value provided in the userinfo endpoint does not match the provided ID token value');
+    }
+
+    public function test_userinfo_endpoint_jwks_response_with_invalid_signature_throws()
+    {
+        $userinfoResponseData = OidcJwtHelper::idToken();
+        $exploded = explode('.', $userinfoResponseData);
+        $exploded[2] = base64_encode(base64_decode($exploded[2]) . 'ABC');
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/jwt'], implode('.', $exploded));
+
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: Token signature could not be validated using the provided keys');
+    }
+
+    public function test_userinfo_endpoint_jwks_response_with_invalid_signature_alg_throws()
+    {
+        $userinfoResponseData = OidcJwtHelper::idToken([], ['alg' => 'ZZ512']);
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/jwt'], $userinfoResponseData);
+
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: Only RS256 signature validation is supported. Token reports using ZZ512');
+    }
+
+    public function test_userinfo_endpoint_response_with_invalid_content_type_throws()
+    {
+        $userinfoResponse = new Response(200, ['Content-Type'  => 'application/beans'], json_encode(OidcJwtHelper::defaultPayload()));
+        $resp = $this->runLogin(['name' => null], [$userinfoResponse]);
+        $resp->assertRedirect('/login');
+        $this->assertSessionError('Userinfo endpoint response validation failed with error: No valid subject value found in userinfo data');
+    }
+
+    protected function withAutodiscovery(): void
     {
         config()->set([
             'oidc.issuer'                 => OidcJwtHelper::defaultIssuer(),
             'oidc.discover'               => true,
             'oidc.authorization_endpoint' => null,
             'oidc.token_endpoint'         => null,
+            'oidc.userinfo_endpoint'      => null,
             'oidc.jwt_public_key'         => null,
         ]);
     }
 
-    protected function runLogin($claimOverrides = []): TestResponse
+    protected function runLogin($claimOverrides = [], $additionalHttpResponses = []): TestResponse
     {
         $this->post('/oidc/login');
         $state = session()->get('oidc_state');
-        $this->mockHttpClient([$this->getMockAuthorizationResponse($claimOverrides)]);
+        $this->mockHttpClient([$this->getMockAuthorizationResponse($claimOverrides), ...$additionalHttpResponses]);
 
         return $this->get('/oidc/callback?code=SplxlOBeZQQYbYS6WxSbIA&state=' . $state);
     }
@@ -718,6 +879,7 @@ class OidcTest extends TestCase
         ], json_encode(array_merge([
             'token_endpoint'         => OidcJwtHelper::defaultIssuer() . '/oidc/token',
             'authorization_endpoint' => OidcJwtHelper::defaultIssuer() . '/oidc/authorize',
+            'userinfo_endpoint'      => OidcJwtHelper::defaultIssuer() . '/oidc/userinfo',
             'jwks_uri'               => OidcJwtHelper::defaultIssuer() . '/oidc/keys',
             'issuer'                 => OidcJwtHelper::defaultIssuer(),
             'end_session_endpoint'   => OidcJwtHelper::defaultIssuer() . '/oidc/logout',

tests/Unit/OidcIdTokenTest.php

@@ -113,7 +113,7 @@ class OidcIdTokenTest extends TestCase
             // 2. aud claim present
             ['Missing token audience value', ['aud' => null]],
             // 2. aud claim validates all values against those expected (Only expect single)
-            ['Token audience value has 2 values, Expected 1', ['aud' => ['abc', 'def']]],
+            ['Token audience value has 2 values, Expected 1', ['aud' => ['xxyyzz.aaa.bbccdd.123', 'def']]],
             // 2. aud claim matches client id
             ['Token audience value did not match the expected client_id', ['aud' => 'xxyyzz.aaa.bbccdd.456']],
             // 4. azp claim matches client id if present