Merge branch 'hotfix/32'

Close #32

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 All notable changes to this project will be documented in this file, in reverse chronological order by release.
 
-## 2.7.1 - TBD
+## 2.7.1 - 2018-05-14
 
 ### Added
 
@@ -22,7 +22,7 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Fixed
 
-- Nothing.
+- [#32](https://github.com/zendframework/zend-mime/pull/32) corrects a potential infinite loop when parsing lines consisting of only spaces and dots.
 
 ## 2.7.0 - 2017-11-28
 

src/Mime.php

@@ -125,21 +125,27 @@ public static function encodeQuotedPrintable(
                 $ptr = $lineLength;
             }
 
-            // Try to prevent that the first character of a line is a dot
-            // Outlook Bug: http://engineering.como.com/ghost-vs-outlook/
-            while ($ptr > 1 && $ptr < strlen($str) && $str[$ptr] === '.') {
-                --$ptr;
-            }
-
             // Ensure we are not splitting across an encoded character
             $pos = strrpos(substr($str, 0, $ptr), '=');
             if ($pos !== false && $pos >= $ptr - 2) {
                 $ptr = $pos;
             }
 
-            // Check if there is a space at the end of the line and rewind
-            if ($ptr > 0 && $str[$ptr - 1] == ' ') {
-                --$ptr;
+            if (ord($str[0]) == 0x2E) { // 0x2E is a dot
+                $str  = '=2E' . substr($str, 1);
+                $ptr += 2;
+            }
+
+            // copied from swiftmailer https://git.io/vAXU1
+            switch (ord(substr($str, $ptr - 1))) {
+                case 0x09: // Horizontal Tab
+                    $str  = substr_replace($str, '=09', $ptr - 1, 1);
+                    $ptr += 2;
+                    break;
+                case 0x20: // Space
+                    $str  = substr_replace($str, '=20', $ptr - 1, 1);
+                    $ptr += 2;
+                    break;
             }
 
             // Add string and continue

test/MimeTest.php

@@ -87,17 +87,29 @@ public function testQuotedPrintableNoDotAtBeginningOfLine()
         $text = str_repeat('a', Mime\Mime::LINELENGTH) . '.bbb';
         $qp = Mime\Mime::encodeQuotedPrintable($text);
 
-        $expected = str_repeat('a', Mime\Mime::LINELENGTH - 1) . "=\na.bbb";
+        $expected = str_repeat('a', Mime\Mime::LINELENGTH) . "=\n=2Ebbb";
+
+        $this->assertEquals($expected, $qp);
+    }
+
+    public function testQuotedPrintableSpacesAndDots()
+    {
+        $text = str_repeat(' ', Mime\Mime::LINELENGTH) . str_repeat('.', Mime\Mime::LINELENGTH);
+        $qp = Mime\Mime::encodeQuotedPrintable($text);
+
+        $expected = str_repeat(' ', Mime\Mime::LINELENGTH - 1)
+            . "=20=\n=2E"
+            . str_repeat('.', Mime\Mime::LINELENGTH - 1);
 
         $this->assertEquals($expected, $qp);
     }
 
     public function testQuotedPrintableDoesNotBreakOctets()
     {
-        $text = str_repeat('a', Mime\Mime::LINELENGTH - 3) . '=.bbb';
+        $text = str_repeat('a', Mime\Mime::LINELENGTH - 2) . '=.bbb';
         $qp = Mime\Mime::encodeQuotedPrintable($text);
 
-        $expected = str_repeat('a', Mime\Mime::LINELENGTH - 3) . "=\n=3D.bbb";
+        $expected = str_repeat('a', Mime\Mime::LINELENGTH - 2) . "=\n=3D.bbb";
 
         $this->assertEquals($expected, $qp);
     }