diff --git a/Lib/http/client.py b/Lib/http/client.py index f0d2642..0a044e9 100644 --- a/Lib/http/client.py +++ b/Lib/http/client.py @@ -151,6 +151,10 @@ _contains_disallowed_url_pchar_re = re.compile('[\x00-\x20\x7f]') # _is_allowed_url_pchars_re = re.compile(r"^[/!$&'()*+,;=:@%a-zA-Z0-9._~-]+$") # We are more lenient for assumed real world compatibility purposes. +# These characters are not allowed within HTTP method names +# to prevent http header injection. +_contains_disallowed_method_pchar_re = re.compile('[\x00-\x1f]') + # We always set the Content-Length header for these methods because some # servers will otherwise respond with a 411 _METHODS_EXPECTING_BODY = {'PATCH', 'POST', 'PUT'} @@ -1117,6 +1121,8 @@ class HTTPConnection: else: raise CannotSendRequest(self.__state) + self._validate_method(method) + # Save the method we use, we need it later in the response phase self._method = method if not url: @@ -1207,6 +1213,15 @@ class HTTPConnection: # For HTTP/1.0, the server will assume "not chunked" pass + def _validate_method(self, method): + """Validate a method name for putrequest.""" + # prevent http header injection + match = _contains_disallowed_method_pchar_re.search(method) + if match: + raise ValueError( + f"method can't contain control characters. {method!r} " + f"(found at least {match.group()!r})") + def putheader(self, header, *values): """Send a request header line to the server. diff --git a/Lib/test/test_httplib.py b/Lib/test/test_httplib.py index 5795b7a..af0350f 100644 --- a/Lib/test/test_httplib.py +++ b/Lib/test/test_httplib.py @@ -359,6 +359,28 @@ class HeaderTests(TestCase): self.assertEqual(lines[2], "header: Second: val") +class HttpMethodTests(TestCase): + def test_invalid_method_names(self): + methods = ( + 'GET\r', + 'POST\n', + 'PUT\n\r', + 'POST\nValue', + 'POST\nHOST:abc', + 'GET\nrHost:abc\n', + 'POST\rRemainder:\r', + 'GET\rHOST:\n', + '\nPUT' + ) + + for method in methods: + with self.assertRaisesRegex( + ValueError, "method can't contain control characters"): + conn = client.HTTPConnection('example.com') + conn.sock = FakeSocket(None) + conn.request(method=method, url="/") + + class TransferEncodingTest(TestCase): expected_body = b"It's just a flesh wound"