Updates JWT::verify to handle openssl errors (#159)

Author: bshaffer

src/JWT.php

@@ -88,7 +88,7 @@ public static function decode($jwt, $key, $allowed_algs = array())
             throw new UnexpectedValueException('Invalid claims encoding');
         }
         $sig = static::urlsafeB64Decode($cryptob64);
-        
+
         if (empty($header->alg)) {
             throw new UnexpectedValueException('Empty algorithm');
         }
@@ -230,11 +230,15 @@ private static function verify($msg, $signature, $key, $alg)
         switch($function) {
             case 'openssl':
                 $success = openssl_verify($msg, $signature, $key, $algorithm);
-                if (!$success) {
-                    throw new DomainException("OpenSSL unable to verify data: " . openssl_error_string());
-                } else {
-                    return $signature;
+                if ($success === 1) {
+                    return true;
+                } elseif ($success === 0) {
+                    return false;
                 }
+                // returns 1 on success, 0 on failure, -1 on error.
+                throw new DomainException(
+                    'OpenSSL error: ' . openssl_error_string()
+                );
             case 'hash_hmac':
             default:
                 $hash = hash_hmac($algorithm, $msg, $key, true);

tests/JWTTest.php

@@ -1,8 +1,13 @@
 <?php
-use \Firebase\JWT\JWT;
+namespace Firebase\JWT;
+
+use ArrayObject;
+use PHPUnit_Framework_TestCase;
 
 class JWTTest extends PHPUnit_Framework_TestCase
 {
+    public static $opensslVerifyReturnValue;
+
     public function testEncodeDecode()
     {
         $msg = JWT::encode('abc', 'my_key');
@@ -253,12 +258,32 @@ public function testMissingAlgorithm()
     public function testAdditionalHeaders()
     {
         $msg = JWT::encode('abc', 'my_key', 'HS256', null, array('cty' => 'test-eit;v=1'));
-        $this->assertEquals(JWT::decode($msg, 'my_key', array('HS256')), 'abc');        
+        $this->assertEquals(JWT::decode($msg, 'my_key', array('HS256')), 'abc');
     }
 
     public function testInvalidSegmentCount()
     {
         $this->setExpectedException('UnexpectedValueException');
         JWT::decode('brokenheader.brokenbody', 'my_key', array('HS256'));
     }
+
+    public function testVerifyError()
+    {
+        $this->setExpectedException('DomainException');
+        $pkey = openssl_pkey_new();
+        $msg = JWT::encode('abc', $pkey, 'RS256');
+        self::$opensslVerifyReturnValue = -1;
+        JWT::decode($msg, $pkey, array('RS256'));
+    }
+}
+
+/*
+ * Allows the testing of openssl_verify with an error return value
+ */
+function openssl_verify($msg, $signature, $key, $algorithm)
+{
+    if (null !== JWTTest::$opensslVerifyReturnValue) {
+        return JWTTest::$opensslVerifyReturnValue;
+    }
+    return \openssl_verify($msg, $signature, $key, $algorithm);
 }