Adding getSignature().

res/openssl.phar.pubkey

@@ -0,0 +1,4 @@
+-----BEGIN PUBLIC KEY-----
+MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBAKuZkrHT54KtuBCTrR36+4tibd+2un9b
+aLFs3X+RHc/jDCXL8pJATz049ckfcfd2ZCMIzH1PHew8H+EMhy4CbSECAwEAAQ==
+-----END PUBLIC KEY-----

src/lib/Herrera/Box/Box.php

@@ -9,9 +9,11 @@
 use Herrera\Box\Exception\OpenSslException;
 use Herrera\Box\Exception\UnexpectedValueException;
 use Phar;
+use PharException;
 use RecursiveDirectoryIterator;
 use RecursiveIteratorIterator;
 use RegexIterator;
+use RuntimeException;
 use SplFileInfo;
 use SplObjectStorage;
 use Traversable;
@@ -44,6 +46,19 @@ class Box
      */
     private $phar;
 
+    /**
+     * The available signature types.
+     *
+     * @var array
+     */
+    private static $types = array(
+        0x01 => array('MD5', 16),
+        0x02 => array('SHA1', 20),
+        0x03 => array('SHA256', 32),
+        0x04 => array('SHA512', 64),
+        0x10 => array('OpenSSL', null),
+    );
+
     /**
      * The placeholder values.
      *
@@ -254,6 +269,71 @@ public function getPhar()
         return $this->phar;
     }
 
+    /**
+     * Returns the signature of the phar.
+     *
+     * This method does not use the extension to extract the phar's signature.
+     *
+     * @param string  $path The phar file path.
+     *
+     * @return array The signature.
+     *
+     * @throws PharException    If the phar is not valid.
+     * @throws RuntimeException If the file could not be read.
+     */
+    public static function getSignature($path)
+    {
+        $signature = array();
+
+        $raw = self::readEnd($path, -12, 12);
+
+        $flag = substr($raw, -4, 4);
+
+        $type = unpack('V', substr($raw, -8, 4));
+        $type = $type[1];
+
+        $size = unpack('V', substr($raw, 0, 4));
+        $size = $size[1];
+
+        if ('GBMB' === $flag) {
+            if (isset(self::$types[$type])) {
+                $signature['hash_type'] = self::$types[$type][0];
+
+                if (self::$types[$type][1]) {
+                    $size = self::$types[$type][1];
+                }
+
+                $signature['hash'] = self::readEnd(
+                    $path,
+                    self::$types[$type][1] ? -8 - $size : -12 - $size,
+                    $size
+                );
+
+                $signature['hash'] = unpack('H*', $signature['hash']);
+                $signature['hash'] = strtoupper($signature['hash'][1]);
+            } else {
+                throw new PharException(
+                    sprintf(
+                        'The signature type (%x) of "%s" is not recognized.',
+                        $type,
+                        $path
+                    )
+                );
+            }
+        } else {
+            if (ini_get('phar.require_hash')) {
+                throw new PharException(
+                    sprintf(
+                        'The phar "%s" is not signed.',
+                        $path
+                    )
+                );
+            }
+        }
+
+        return $signature;
+    }
+
     /**
      * Replaces the placeholders with their values.
      *
@@ -392,4 +472,59 @@ public function signUsingFile($file, $password = null)
 
         $this->sign($key, $password);
     }
+
+    /**
+     * Reads from the end of a file.
+     *
+     * @param string  $file   The file handle.
+     * @param integer $offset The end offset.
+     * @param integer $bytes  The number of bytes to read.
+     *
+     * @return string The read bytes.
+     *
+     * @throws RuntimeException If the file could not be read.
+     */
+    private static function readEnd($file, $offset, $bytes)
+    {
+        if (false === ($size = @filesize($file))) {
+            $error = error_get_last();
+
+            throw new RuntimeException(
+                sprintf(
+                    'The size of the file "%s" could not be retrieved: %s',
+                    $file,
+                    $error['message']
+                )
+            );
+        }
+
+        $read = @file_get_contents($file, false, null, $size + $offset, $bytes);
+
+        if (false === $read) {
+            $error = error_get_last();
+
+            throw new RuntimeException(
+                sprintf(
+                    'The file "%s" could not be read at offset %d for %d bytes: %s',
+                    $file,
+                    $size + $offset,
+                    $bytes,
+                    $error['message']
+                )
+            );
+        }
+
+        if (($actual = strlen($read)) !== $bytes) {
+            throw new RuntimeException(
+                sprintf(
+                    'Could only read %d of %d bytes from "%s".',
+                    $actual,
+                    $bytes,
+                    $file
+                )
+            );
+        }
+
+        return $read;
+    }
 }

src/tests/Herrera/Box/Tests/BoxTest.php

@@ -60,6 +60,37 @@ public function getPrivateKey()
         );
     }
 
+    public function getSignatures()
+    {
+        return array(
+            array(
+                RES_DIR . '/md5.phar',
+                'MD5',
+                '6772FC5AB8AB8D72BB69B6A0C323C796'
+            ),
+            array(
+                RES_DIR . '/sha1.phar',
+                'SHA1',
+                'A158DF4720C619E84A777982402B5D32394805E5'
+            ),
+            array(
+                RES_DIR . '/sha256.phar',
+                'SHA256',
+                'D0A6AB31437CA8485779E7603670ABDE05C911EA7FCEC051B8D3FB14A1480B7D'
+            ),
+            array(
+                RES_DIR . '/sha512.phar',
+                'SHA512',
+                'B4CAE177138A773283A748C8770A7142F0CC36D6EE88E37900BCF09A92D840D237CE3F3B47C2C7B39AC2D2C0F9A16D63FE70E1A455723DD36840B6E2E64E2130'
+            ),
+            array(
+                RES_DIR . '/openssl.phar',
+                'OpenSSL',
+                '54AF1D4E5459D3A77B692E46FDB9C965D1C7579BD1F2AD2BECF4973677575444FE21E104B7655BA3D088090C28DF63D14876B277C423C8BFBCDB9E3E63F9D61A'
+            ),
+        );
+    }
+
     public function testAddCompactor()
     {
         $compactor = new Compactor();
@@ -319,6 +350,46 @@ public function testGetPhar()
         $this->assertSame($this->phar, $this->box->getPhar());
     }
 
+    /**
+     * @dataProvider getSignatures
+     */
+    public function testGetSignature($file, $type, $hash)
+    {
+        $signature = Box::getSignature($file);
+
+        $this->assertEquals(
+            array(
+                'hash_type' => $type,
+                'hash' => $hash,
+            ),
+            $signature
+        );
+    }
+
+    public function testGetSignatureInvalid()
+    {
+        $path = RES_DIR . '/invalid.phar';
+
+        $this->setExpectedException(
+            'PharException',
+            "The signature type (ffffffff) of \"$path\" is not recognized."
+        );
+
+        Box::getSignature($path);
+    }
+
+    public function testGetSignatureMissing()
+    {
+        $path = RES_DIR . '/missing.phar';
+
+        $this->setExpectedException(
+            'PharException',
+            "The phar \"$path\" is not signed."
+        );
+
+        Box::getSignature($path);
+    }
+
     public function testReplaceValues()
     {
         $this->setPropertyValue(