90 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			PHP
		
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			PHP
		
	
	
	
| <?php
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| 
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| namespace BookStack\Access\Oidc;
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| 
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| class OidcIdToken extends OidcJwtWithClaims implements ProvidesClaims
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| {
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|     /**
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|      * Validate all possible parts of the id token.
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|      *
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|      * @throws OidcInvalidTokenException
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|      */
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|     public function validate(string $clientId): bool
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|     {
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|         parent::validateCommonTokenDetails($clientId);
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|         $this->validateTokenClaims($clientId);
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| 
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|         return true;
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|     }
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| 
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|     /**
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|      * Validate the claims of the token.
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|      * As per https://openid.net/specs/openid-connect-basic-1_0.html#IDTokenValidation.
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|      *
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|      * @throws OidcInvalidTokenException
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|      */
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|     protected function validateTokenClaims(string $clientId): void
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|     {
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|         // 1. The Issuer Identifier for the OpenID Provider (which is typically obtained during Discovery)
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|         // MUST exactly match the value of the iss (issuer) Claim.
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|         // Already done in parent.
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| 
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|         // 2. The Client MUST validate that the aud (audience) Claim contains its client_id value registered
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|         // at the Issuer identified by the iss (issuer) Claim as an audience. The ID Token MUST be rejected
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|         // if the ID Token does not list the Client as a valid audience, or if it contains additional
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|         // audiences not trusted by the Client.
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|         // Partially done in parent.
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|         $aud = is_string($this->payload['aud']) ? [$this->payload['aud']] : $this->payload['aud'];
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|         if (count($aud) !== 1) {
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|             throw new OidcInvalidTokenException('Token audience value has ' . count($aud) . ' values, Expected 1');
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|         }
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| 
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|         // 3. If the ID Token contains multiple audiences, the Client SHOULD verify that an azp Claim is present.
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|         // NOTE: Addressed by enforcing a count of 1 above.
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| 
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|         // 4. If an azp (authorized party) Claim is present, the Client SHOULD verify that its client_id
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|         // is the Claim Value.
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|         if (isset($this->payload['azp']) && $this->payload['azp'] !== $clientId) {
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|             throw new OidcInvalidTokenException('Token authorized party exists but does not match the expected client_id');
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|         }
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| 
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|         // 5. The current time MUST be before the time represented by the exp Claim
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|         // (possibly allowing for some small leeway to account for clock skew).
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|         if (empty($this->payload['exp'])) {
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|             throw new OidcInvalidTokenException('Missing token expiration time value');
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|         }
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| 
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|         $skewSeconds = 120;
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|         $now = time();
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|         if ($now >= (intval($this->payload['exp']) + $skewSeconds)) {
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|             throw new OidcInvalidTokenException('Token has expired');
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|         }
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| 
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|         // 6. The iat Claim can be used to reject tokens that were issued too far away from the current time,
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|         // limiting the amount of time that nonces need to be stored to prevent attacks.
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|         // The acceptable range is Client specific.
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|         if (empty($this->payload['iat'])) {
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|             throw new OidcInvalidTokenException('Missing token issued at time value');
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|         }
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| 
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|         $dayAgo = time() - 86400;
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|         $iat = intval($this->payload['iat']);
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|         if ($iat > ($now + $skewSeconds) || $iat < $dayAgo) {
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|             throw new OidcInvalidTokenException('Token issue at time is not recent or is invalid');
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|         }
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| 
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|         // 7. If the acr Claim was requested, the Client SHOULD check that the asserted Claim Value is appropriate.
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|         // The meaning and processing of acr Claim Values is out of scope for this document.
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|         // NOTE: Not used for our case here. acr is not requested.
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| 
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|         // 8. When a max_age request is made, the Client SHOULD check the auth_time Claim value and request
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|         // re-authentication if it determines too much time has elapsed since the last End-User authentication.
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|         // NOTE: Not used for our case here. A max_age request is not made.
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| 
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|         // Custom: Ensure the "sub" (Subject) Claim exists and has a value.
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|         if (empty($this->payload['sub'])) {
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|             throw new OidcInvalidTokenException('Missing token subject value');
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|         }
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|     }
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| }
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