python3/SOURCES/00320-CVE-2019-9636-and-CVE...

138 lines
5.6 KiB
Diff

diff --git a/Doc/library/urllib.parse.rst b/Doc/library/urllib.parse.rst
index d991254..647af61 100644
--- a/Doc/library/urllib.parse.rst
+++ b/Doc/library/urllib.parse.rst
@@ -121,6 +121,11 @@ or on combining URL components into a URL string.
Unmatched square brackets in the :attr:`netloc` attribute will raise a
:exc:`ValueError`.
+ Characters in the :attr:`netloc` attribute that decompose under NFKC
+ normalization (as used by the IDNA encoding) into any of ``/``, ``?``,
+ ``#``, ``@``, or ``:`` will raise a :exc:`ValueError`. If the URL is
+ decomposed before parsing, no error will be raised.
+
.. versionchanged:: 3.2
Added IPv6 URL parsing capabilities.
@@ -133,6 +138,10 @@ or on combining URL components into a URL string.
Out-of-range port numbers now raise :exc:`ValueError`, instead of
returning :const:`None`.
+ .. versionchanged:: 3.6.9
+ Characters that affect netloc parsing under NFKC normalization will
+ now raise :exc:`ValueError`.
+
.. function:: parse_qs(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None)
@@ -256,10 +265,19 @@ or on combining URL components into a URL string.
Unmatched square brackets in the :attr:`netloc` attribute will raise a
:exc:`ValueError`.
+ Characters in the :attr:`netloc` attribute that decompose under NFKC
+ normalization (as used by the IDNA encoding) into any of ``/``, ``?``,
+ ``#``, ``@``, or ``:`` will raise a :exc:`ValueError`. If the URL is
+ decomposed before parsing, no error will be raised.
+
.. versionchanged:: 3.6
Out-of-range port numbers now raise :exc:`ValueError`, instead of
returning :const:`None`.
+ .. versionchanged:: 3.6.9
+ Characters that affect netloc parsing under NFKC normalization will
+ now raise :exc:`ValueError`.
+
.. function:: urlunsplit(parts)
diff --git a/Lib/test/test_urlparse.py b/Lib/test/test_urlparse.py
index be50b47..68f633c 100644
--- a/Lib/test/test_urlparse.py
+++ b/Lib/test/test_urlparse.py
@@ -1,3 +1,5 @@
+import sys
+import unicodedata
import unittest
import urllib.parse
@@ -984,6 +986,34 @@ class UrlParseTestCase(unittest.TestCase):
expected.append(name)
self.assertCountEqual(urllib.parse.__all__, expected)
+ def test_urlsplit_normalization(self):
+ # Certain characters should never occur in the netloc,
+ # including under normalization.
+ # Ensure that ALL of them are detected and cause an error
+ illegal_chars = '/:#?@'
+ hex_chars = {'{:04X}'.format(ord(c)) for c in illegal_chars}
+ denorm_chars = [
+ c for c in map(chr, range(128, sys.maxunicode))
+ if (hex_chars & set(unicodedata.decomposition(c).split()))
+ and c not in illegal_chars
+ ]
+ # Sanity check that we found at least one such character
+ self.assertIn('\u2100', denorm_chars)
+ self.assertIn('\uFF03', denorm_chars)
+
+ # bpo-36742: Verify port separators are ignored when they
+ # existed prior to decomposition
+ urllib.parse.urlsplit('http://\u30d5\u309a:80')
+ with self.assertRaises(ValueError):
+ urllib.parse.urlsplit('http://\u30d5\u309a\ufe1380')
+
+ for scheme in ["http", "https", "ftp"]:
+ for netloc in ["netloc{}false.netloc", "n{}user@netloc"]:
+ for c in denorm_chars:
+ url = "{}://{}/path".format(scheme, netloc.format(c))
+ with self.subTest(url=url, char='{:04X}'.format(ord(c))):
+ with self.assertRaises(ValueError):
+ urllib.parse.urlsplit(url)
class Utility_Tests(unittest.TestCase):
"""Testcase to test the various utility functions in the urllib."""
diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py
index 85e68c8..fa8827a 100644
--- a/Lib/urllib/parse.py
+++ b/Lib/urllib/parse.py
@@ -391,6 +391,24 @@ def _splitnetloc(url, start=0):
delim = min(delim, wdelim) # use earliest delim position
return url[start:delim], url[delim:] # return (domain, rest)
+def _checknetloc(netloc):
+ if not netloc or not any(ord(c) > 127 for c in netloc):
+ return
+ # looking for characters like \u2100 that expand to 'a/c'
+ # IDNA uses NFKC equivalence, so normalize for this check
+ import unicodedata
+ n = netloc.replace('@', '') # ignore characters already included
+ n = n.replace(':', '') # but not the surrounding text
+ n = n.replace('#', '')
+ n = n.replace('?', '')
+ netloc2 = unicodedata.normalize('NFKC', n)
+ if n == netloc2:
+ return
+ for c in '/?#@:':
+ if c in netloc2:
+ raise ValueError("netloc '" + netloc + "' contains invalid " +
+ "characters under NFKC normalization")
+
def urlsplit(url, scheme='', allow_fragments=True):
"""Parse a URL into 5 components:
<scheme>://<netloc>/<path>?<query>#<fragment>
@@ -420,6 +438,7 @@ def urlsplit(url, scheme='', allow_fragments=True):
url, fragment = url.split('#', 1)
if '?' in url:
url, query = url.split('?', 1)
+ _checknetloc(netloc)
v = SplitResult(scheme, netloc, url, query, fragment)
_parse_cache[key] = v
return _coerce_result(v)
@@ -443,6 +462,7 @@ def urlsplit(url, scheme='', allow_fragments=True):
url, fragment = url.split('#', 1)
if '?' in url:
url, query = url.split('?', 1)
+ _checknetloc(netloc)
v = SplitResult(scheme, netloc, url, query, fragment)
_parse_cache[key] = v
return _coerce_result(v)