Merge pull request #564 from LukeCarrier/windows-paths

Improve handling of paths containing Windows-style drive letters

lib/SimpleSAML/Configuration.php

 <?php
 
+use SimpleSAML\Utils\System;
 
 /**
  * Configuration of SimpleSAMLphp
@@ -568,19 +569,7 @@ class SimpleSAML_Configuration implements \SimpleSAML\Utils\ClearableState
 
         assert(is_string($path));
 
-        /* Prepend path with basedir if it doesn't start with a slash or a Windows drive letter (e.g. "C:\"). We assume
-         * getBaseDir ends with a slash.
-         */
-        if ($path[0] !== '/' &&
-            !(preg_match('@^[a-z]:[\\\\/]@i', $path, $matches) && is_dir($matches[0]))
-        ) {
-            $path = $this->getBaseDir().$path;
-        }
-
-        // remove trailing slashes
-        $path = rtrim($path, '/');
-
-        return $path;
+        return System::resolvePath($path, $this->getBaseDir());
     }
 
 

lib/SimpleSAML/Utils/System.php

@@ -122,13 +122,20 @@ class System
             $base = $config->getBaseDir();
         }
 
+        // normalise directory separator
+        $base = str_replace('\\', '/', $base);
+        $path = str_replace('\\', '/', $path);
+
         // remove trailing slashes
         $base = rtrim($base, '/');
+        $path = rtrim($path, '/');
 
         // check for absolute path
         if (substr($path, 0, 1) === '/') {
             // absolute path. */
             $ret = '/';
+        } elseif (static::pathContainsDriveLetter($path)) {
+            $ret = '';
         } else {
             // path relative to base
             $ret = $base;
@@ -141,7 +148,7 @@ class System
             } elseif ($d === '..') {
                 $ret = dirname($ret);
             } else {
-                if (substr($ret, -1) !== '/') {
+                if ($ret && substr($ret, -1) !== '/') {
                     $ret .= '/';
                 }
                 $ret .= $d;
@@ -215,4 +222,18 @@ class System
             opcache_invalidate($filename);
         }
     }
+
+    /**
+     * Check if the supplied path contains a Windows-style drive letter.
+     *
+     * @param string $path
+     *
+     * @return bool
+     */
+    private static function pathContainsDriveLetter($path)
+    {
+        $letterAsciiValue = ord(strtoupper(substr($path, 0, 1)));
+        return substr($path, 1, 1) === ':'
+                && $letterAsciiValue >= 65 && $letterAsciiValue <= 90;
+    }
 }

tests/lib/SimpleSAML/ConfigurationTest.php

@@ -220,6 +220,9 @@ class Test_SimpleSAML_Configuration extends SimpleSAML\Test\Utils\ClearStateTest
 
         $this->assertEquals($c->resolvePath('slash/'), '/basedir/slash');
         $this->assertEquals($c->resolvePath('slash//'), '/basedir/slash');
+
+        $this->assertEquals($c->resolvePath('C:\\otherdir'), 'C:/otherdir');
+        $this->assertEquals($c->resolvePath('C:/otherdir'), 'C:/otherdir');
     }
 
     /**