Changeset 123:446c42e017fd

Timestamp:

2007-08-02 19:17:43 (1 year ago)

Author:

Stefan Schwarzer <sschwarzer@sschwarzer.net>

branch:

default

Message:

Moved `is_safe_path` from `websourcebrowser.py` to `urlpath.py`.

Files:

• urlpath.py (modified) (3 diffs)
• websourcebrowser.py (modified) (3 diffs)

urlpath.py

@@ -24 +24 @@
-import urllib
-import os
+import re
-
-
+# separator in URLs
-sep = "/"
-
-class NotUnderRoot(Exception):
-    pass
+
+def _normalize_path(path):
+    """
+    Return the `path` in "normalized" form:
+    - change each sequence of path separators to a single path separator
+    - change path by evaluating "." and ".." occurences
+    - make path absolute
+    """
+    if os.sep == "\\":
+        replacement = "\\\\"
+    else:
+        replacement = os.sep
+    path = re.sub("(?:%s)+" % re.escape(os.sep), replacement, path)
+    path = os.path.normcase(os.path.normpath(path))
+    return os.path.abspath(path)
+
+def _is_file_system_root(path):
+    r"""
+    Return `True` if `path` is a file system root directory, else
+    `False`.
+
+    Under Posix, the file system root directory is "/", under
+    Windows, it's r"x:\", where x is any drive letter.
+    """
+    path = _normalize_path(path)
+    drive, rest = os.path.splitdrive(path)
+    return rest == os.sep
+
+def is_safe_path(root, path):
+    """
+    Return `True` if the `path` is a subdirectory of or a file
+    under the document root directory `root`, else return `False`.
+
+    >>> import urlpath
+    >>> urlpath.is_safe_path("/the/root", "/the/root/some_file")
+    True
+    >>> urlpath.is_safe_path("/the/root", "/somewhere/else/some_file")
+    False
+    """
+    root = _normalize_path(root)
+    path = _normalize_path(path)
+    if root == path:
+        return True
+    if _is_file_system_root(root):
+        return path.startswith(root)
+    else:
+        return path.startswith(root + os.sep)
-
-def to_url(root, path):
@@ -43 +92 @@
-    >>> urlpath.to_url("/the/root", "/the/root/some dir/some file")
-    '/some%20dir/some%20file'
-
-    It also works on Windows:
-
-    >>> import os
-    >>> oldsep = os.sep; os.sep = "\\"
-    >>> urlpath.to_url(r"C:\the\root", r"C:\the\root\somedir\somefile")
-    '/somedir/somefile'
-    >>> os.sep = oldsep
-
-    Trailing path separators on the `root` or `path` don't matter:
@@ -92 +133 @@
-    '/the/root/some dir/some file'
-
-    It also works on Windows:
-
-    >>> import os
-    >>> oldsep = os.sep; os.sep = "\\"
-    >>> urlpath.to_file_system(r"C:\the\root", "/somedir/somefile")
-    'C:\\the\\root\\somedir\\somefile'
-    >>> os.sep = oldsep
-
-    Trailing path separators on the `root` or `url` don't matter:
-

websourcebrowser.py

@@ -67 +67 @@
-    return css_path
-
-def is_safe_path(absolute_path):
-    """
-    Return `True` if the `absolute_path` is a subdirectory of or a
-    file in the document root directory, else return `False`.
-    """
-    if absolute_path.count(os.sep) == 1:
-        # file system root directory
-        # Attention: On Posix, we could now just return `True`, but on
-        #  Windows, we have a file system root directory _per drive letter_
-        return absolute_path.startswith(config.root)
-    else:
-        return absolute_path.startswith(config.root + os.sep)
-
-
-class SourceBrowserHandler(BaseHTTPServer.BaseHTTPRequestHandler):
@@ -182 +169 @@
-                source_path = urllib.unquote(source_path)
-                source_path = os.path.join(config.root, source_path[1:])
-is_safe_path(
+urlpath.is_safe_path(config.root, 
-                    content_type = mimetypes.guess_type(source_path)[0]
-                    if content_type is None:
@@ -192 +179 @@
-            return
-        path = urlpath.to_file_system(config.root, self.path)
-is_safe_path(
+urlpath.is_safe_path(config.root, 
-            # don't show items "above" the current directory; thereby
-            #  avoiding information disclosure (double dot attack)