Issue 214 (remove traversals in prepended links)

min/lib/Minify/CSS/UriRewriter.php

@@ -12,13 +12,6 @@
  */
 class Minify_CSS_UriRewriter {
     
-    /**
-     * Defines which class to call as part of callbacks, change this
-     * if you extend Minify_CSS_UriRewriter
-     * @var string
-     */
-    protected static $className = 'Minify_CSS_UriRewriter';
-    
     /**
      * rewrite() and rewriteRelative() append debugging information here
      * @var string
@@ -26,7 +19,7 @@ class Minify_CSS_UriRewriter {
     public static $debugText = '';
     
     /**
-     * Rewrite file relative URIs as root relative in CSS files
+     * In CSS content, rewrite file relative URIs as root relative
      * 
      * @param string $css
      * 
@@ -83,7 +76,7 @@ class Minify_CSS_UriRewriter {
     }
     
     /**
-     * Prepend a path to relative URIs in CSS files
+     * In CSS content, prepend a path to relative URIs
      * 
      * @param string $css
      * 
@@ -107,73 +100,8 @@ class Minify_CSS_UriRewriter {
         return $css;
     }
     
-    
     /**
-     * @var string directory of this stylesheet
+     * Get a root relative URI from a file relative URI
-     */
-    private static $_currentDir = '';
-    
-    /**
-     * @var string DOC_ROOT
-     */
-    private static $_docRoot = '';
-    
-    /**
-     * @var array directory replacements to map symlink targets back to their
-     * source (within the document root) E.g. '/var/www/symlink' => '/var/realpath'
-     */
-    private static $_symlinks = array();
-    
-    /**
-     * @var string path to prepend
-     */
-    private static $_prependPath = null;
-    
-    private static function _trimUrls($css)
-    {
-        return preg_replace('/
-            url\\(      # url(
-            \\s*
-            ([^\\)]+?)  # 1 = URI (assuming does not contain ")")
-            \\s*
-            \\)         # )
-        /x', 'url($1)', $css);
-    }
-    
-    private static function _processUriCB($m)
-    {
-        // $m matched either '/@import\\s+([\'"])(.*?)[\'"]/' or '/url\\(\\s*([^\\)\\s]+)\\s*\\)/'
-        $isImport = ($m[0][0] === '@');
-        // determine URI and the quote character (if any)
-        if ($isImport) {
-            $quoteChar = $m[1];
-            $uri = $m[2];
-        } else {
-            // $m[1] is either quoted or not
-            $quoteChar = ($m[1][0] === "'" || $m[1][0] === '"')
-                ? $m[1][0]
-                : '';
-            $uri = ($quoteChar === '')
-                ? $m[1]
-                : substr($m[1], 1, strlen($m[1]) - 2);
-        }
-        // analyze URI
-        if ('/' !== $uri[0]                  // root-relative
-            && false === strpos($uri, '//')  // protocol (non-data)
-            && 0 !== strpos($uri, 'data:')   // data protocol
-        ) {
-            // URI is file-relative: rewrite depending on options
-            $uri = (self::$_prependPath !== null)
-                ? (self::$_prependPath . $uri)
-                : self::rewriteRelative($uri, self::$_currentDir, self::$_docRoot, self::$_symlinks);
-        }
-        return $isImport
-            ? "@import {$quoteChar}{$uri}{$quoteChar}"
-            : "url({$quoteChar}{$uri}{$quoteChar})";
-    }
-    
-    /**
-     * Rewrite a file relative URI as root relative
      *
      * <code>
      * Minify_CSS_UriRewriter::rewriteRelative(
@@ -239,18 +167,35 @@ class Minify_CSS_UriRewriter {
 
         $uri = strtr($path, '/\\', '//');
 
-        // remove /./ and /../ where possible
+        $uri = self::removeDots($uri);
-        $uri = str_replace('/./', '/', $uri);
-        // inspired by patch from Oleg Cherniy
-        do {
-            $uri = preg_replace('@/[^/]+/\\.\\./@', '/', $uri, 1, $changed);
-        } while ($changed);
       
         self::$debugText .= "traversals removed : {$uri}\n\n";
         
         return $uri;
     }
 
+    /**
+     * Remove instances of "./" and "../" where possible from a root-relative URI
+     * @param string $uri
+     * @return string
+     */
+    public static function removeDots($uri)
+    {
+        $uri = str_replace('/./', '/', $uri);
+        // inspired by patch from Oleg Cherniy
+        do {
+            $uri = preg_replace('@/[^/]+/\\.\\./@', '/', $uri, 1, $changed);
+        } while ($changed);
+        return $uri;
+    }
+    
+    /**
+     * Defines which class to call as part of callbacks, change this
+     * if you extend Minify_CSS_UriRewriter
+     * @var string
+     */
+    protected static $className = 'Minify_CSS_UriRewriter';
+
     /**
      * Get realpath with any trailing slash removed. If realpath() fails,
      * just remove the trailing slash.
@@ -267,4 +212,79 @@ class Minify_CSS_UriRewriter {
         }
         return rtrim($path, '/\\');
     }
+
+    /**
+     * @var string directory of this stylesheet
+     */
+    private static $_currentDir = '';
+
+    /**
+     * @var string DOC_ROOT
+     */
+    private static $_docRoot = '';
+
+    /**
+     * @var array directory replacements to map symlink targets back to their
+     * source (within the document root) E.g. '/var/www/symlink' => '/var/realpath'
+     */
+    private static $_symlinks = array();
+
+    /**
+     * @var string path to prepend
+     */
+    private static $_prependPath = null;
+
+    private static function _trimUrls($css)
+    {
+        return preg_replace('/
+            url\\(      # url(
+            \\s*
+            ([^\\)]+?)  # 1 = URI (assuming does not contain ")")
+            \\s*
+            \\)         # )
+        /x', 'url($1)', $css);
+    }
+
+    private static function _processUriCB($m)
+    {
+        // $m matched either '/@import\\s+([\'"])(.*?)[\'"]/' or '/url\\(\\s*([^\\)\\s]+)\\s*\\)/'
+        $isImport = ($m[0][0] === '@');
+        // determine URI and the quote character (if any)
+        if ($isImport) {
+            $quoteChar = $m[1];
+            $uri = $m[2];
+        } else {
+            // $m[1] is either quoted or not
+            $quoteChar = ($m[1][0] === "'" || $m[1][0] === '"')
+                ? $m[1][0]
+                : '';
+            $uri = ($quoteChar === '')
+                ? $m[1]
+                : substr($m[1], 1, strlen($m[1]) - 2);
+        }
+        // analyze URI
+        if ('/' !== $uri[0]                  // root-relative
+            && false === strpos($uri, '//')  // protocol (non-data)
+            && 0 !== strpos($uri, 'data:')   // data protocol
+        ) {
+            // URI is file-relative: rewrite depending on options
+            if (self::$_prependPath === null) {
+                $uri = self::rewriteRelative($uri, self::$_currentDir, self::$_docRoot, self::$_symlinks);
+            } else {
+                $uri = self::$_prependPath . $uri;
+                if ($uri[0] === '/') {
+                    $root = '';
+                    $rootRelative = $uri;
+                    $uri = $root . self::removeDots($rootRelative);
+                } elseif (preg_match('@^((https?\:)?//([^/]+))/@', $uri, $m) && (false !== strpos($m[3], '.'))) {
+                    $root = $m[1];
+                    $rootRelative = substr($uri, strlen($root));
+                    $uri = $root . self::removeDots($rootRelative);
+                }
+            }
+        }
+        return $isImport
+            ? "@import {$quoteChar}{$uri}{$quoteChar}"
+            : "url({$quoteChar}{$uri}{$quoteChar})";
+    }
 }

min_unit_tests/_test_files/css_uriRewriter/exp_prepend.css

@@ -0,0 +1,14 @@
+@import "http://cnd.com/A/B/foo.css";
+@import 'http://cnd.com/A/B/bar/foo.css' print;
+@import 'http://cnd.com/A/bar/foo.css' print;
+@import 'http://cnd.com/foo.css' print;
+@import '/css/foo.css'; /* abs, should not alter */
+@import 'http://foo.com/css/foo.css'; /* abs, should not alter */
+@import url(http://cnd.com/A/foo.css) tv, projection;
+@import url("/css/foo.css"); /* abs, should not alter */
+@import url(/css2/foo.css); /* abs, should not alter */
+@import url(data:image/gif;base64,AAAA); /* data, should not alter */
+foo {background:url('http://cnd.com/A/B/bar/foo.png')}
+foo {background:url('http://foo.com/css/foo.css');} /* abs, should not alter */
+foo {background:url("//foo.com/css/foo.css");} /* protocol relative, should not alter */
+foo {background:url(data:image/gif;base64,AAAA);} /* data, should not alter */

min_unit_tests/_test_files/css_uriRewriter/exp_prepend2.css

@@ -0,0 +1,14 @@
+@import "//cnd.com/A/B/foo.css";
+@import '//cnd.com/A/B/bar/foo.css' print;
+@import '//cnd.com/A/bar/foo.css' print;
+@import '//cnd.com/foo.css' print;
+@import '/css/foo.css'; /* abs, should not alter */
+@import 'http://foo.com/css/foo.css'; /* abs, should not alter */
+@import url(//cnd.com/A/foo.css) tv, projection;
+@import url("/css/foo.css"); /* abs, should not alter */
+@import url(/css2/foo.css); /* abs, should not alter */
+@import url(data:image/gif;base64,AAAA); /* data, should not alter */
+foo {background:url('//cnd.com/A/B/bar/foo.png')}
+foo {background:url('http://foo.com/css/foo.css');} /* abs, should not alter */
+foo {background:url("//foo.com/css/foo.css");} /* protocol relative, should not alter */
+foo {background:url(data:image/gif;base64,AAAA);} /* data, should not alter */

min_unit_tests/test_Minify_CSS_UriRewriter.php

@@ -17,7 +17,7 @@ function test_Minify_CSS_UriRewriter()
         ,$thisDir // use DOCUMENT_ROOT = '/full/path/to/min_unit_tests'
     );
     
-    $passed = assertTrue($expected === $actual, 'Minify_CSS_UriRewriter');
+    $passed = assertTrue($expected === $actual, 'Minify_CSS_UriRewriter : rewrite');
     if (__FILE__ === realpath($_SERVER['SCRIPT_FILENAME'])) {
         echo "\n---Input:\n\n{$in}\n";
         echo "\n---Output: " .countBytes($actual). " bytes\n\n{$actual}\n\n";
@@ -30,6 +30,45 @@ function test_Minify_CSS_UriRewriter()
             , Minify_CSS_UriRewriter::$debugText;
     }
 
+
+    Minify_CSS_UriRewriter::$debugText = '';
+    $in = file_get_contents($thisDir . '/_test_files/css_uriRewriter/in.css');
+    $expected = file_get_contents($thisDir . '/_test_files/css_uriRewriter/exp_prepend.css');
+    $actual = Minify_CSS_UriRewriter::prepend($in, 'http://cnd.com/A/B/');
+
+    $passed = assertTrue($expected === $actual, 'Minify_CSS_UriRewriter : prepend1');
+    if (__FILE__ === realpath($_SERVER['SCRIPT_FILENAME'])) {
+        echo "\n---Input:\n\n{$in}\n";
+        echo "\n---Output: " .countBytes($actual). " bytes\n\n{$actual}\n\n";
+        if (!$passed) {
+            echo "---Expected: " .countBytes($expected). " bytes\n\n{$expected}\n\n\n";
+        }
+
+        // show debugging only when test run directly
+        echo "--- Minify_CSS_UriRewriter::\$debugText\n\n"
+            , Minify_CSS_UriRewriter::$debugText;
+    }
+
+
+    Minify_CSS_UriRewriter::$debugText = '';
+    $in = file_get_contents($thisDir . '/_test_files/css_uriRewriter/in.css');
+    $expected = file_get_contents($thisDir . '/_test_files/css_uriRewriter/exp_prepend2.css');
+    $actual = Minify_CSS_UriRewriter::prepend($in, '//cnd.com/A/B/');
+
+    $passed = assertTrue($expected === $actual, 'Minify_CSS_UriRewriter : prepend2');
+    if (__FILE__ === realpath($_SERVER['SCRIPT_FILENAME'])) {
+        echo "\n---Input:\n\n{$in}\n";
+        echo "\n---Output: " .countBytes($actual). " bytes\n\n{$actual}\n\n";
+        if (!$passed) {
+            echo "---Expected: " .countBytes($expected). " bytes\n\n{$expected}\n\n\n";
+        }
+
+        // show debugging only when test run directly
+        echo "--- Minify_CSS_UriRewriter::\$debugText\n\n"
+            , Minify_CSS_UriRewriter::$debugText;
+    }
+
+    
     Minify_CSS_UriRewriter::$debugText = '';
     $in = '../../../../assets/skins/sam/sprite.png';
     $exp = '/yui/assets/skins/sam/sprite.png';