Merge pull request #36 from fulder/master

Quickfix for regexp catastrophic backtracking

Author: peakwinter

nginx.py

@@ -11,6 +11,14 @@
 INDENT = '    '
 
 
+class Error(Exception):
+    pass
+
+
+class ParseError(Error):
+    pass
+
+
 def bump_child_depth(obj, depth):
     children = getattr(obj, 'children', [])
     for child in children:
@@ -67,7 +75,7 @@ def filter(self, btype='', name=''):
         for x in self.children:
             if name and isinstance(x, Key) and x.name == name:
                 filtered.append(x)
-            elif isinstance(x, Container) and x.__class__.__name__ == btype\
+            elif isinstance(x, Container) and x.__class__.__name__ == btype \
                     and x.value == name:
                 filtered.append(x)
             elif not name and btype and x.__class__.__name__ == btype:
@@ -164,7 +172,7 @@ def filter(self, btype='', name=''):
         for x in self.children:
             if name and isinstance(x, Key) and x.name == name:
                 filtered.append(x)
-            elif isinstance(x, Container) and x.__class__.__name__ == btype\
+            elif isinstance(x, Container) and x.__class__.__name__ == btype \
                     and x.value == name:
                 filtered.append(x)
             elif not name and btype and x.__class__.__name__ == btype:
@@ -507,6 +515,11 @@ def loads(data, conf=True):
             index += m.end()
             continue
 
+        if ";" not in data[index:] and index+1 != len(data):
+            # If there is still something to parse, expect ';' otherwise
+            # the Key regexp can get stuck due to regexp catastrophic backtracking
+            raise ParseError("Config syntax, missing ';' at index: {}".format(index))
+
         double = r'\s*"[^"]*"'
         single = r'\s*\'[^\']*\''
         normal = r'\s*[^;\s]*'

tests.py

@@ -7,6 +7,7 @@
 """
 
 # flake8: noqa
+import pytest
 
 import nginx
 import unittest
@@ -177,6 +178,22 @@
 }
 """
 
+TESTBLOCK_CASE_11 = """
+server{
+    listen 80;
+    #OPEN-PORT-443
+    listen 443 ssl;
+    server_name www.xxx.com;
+    root /wwww/wwww;
+
+    location ~ .*\.(js|css)?$ {
+        expires 12h;
+        error_log off;
+        access_log /dev/null  # MISSING SEMICOLON
+    }
+}
+"""
+
 
 class TestPythonNginx(unittest.TestCase):
     def test_basic_load(self):
@@ -290,5 +307,11 @@ def test_types_block(self):
         data_type = inp_data.filter("Types")[0].filter("Key")[0]
         self.assertEqual(data_type.value, "cea")
 
+    def test_missing_semi_colon(self):
+        with pytest.raises(nginx.ParseError) as e:
+            nginx.loads(TESTBLOCK_CASE_11)
+        self.assertEqual(str(e.value), "Config syntax, missing ';' at index: 189")
+
+
 if __name__ == '__main__':
     unittest.main()