File CVE-2020-26116-httplib-header-injection.patch of Package python3-doc.16830

Index: Python-3.4.10/Lib/http/client.py
===================================================================
--- Python-3.4.10.orig/Lib/http/client.py
+++ Python-3.4.10/Lib/http/client.py
@@ -266,6 +266,10 @@ _contains_disallowed_url_pchar_re = re.c
 #  _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'}
@@ -1026,6 +1030,8 @@ 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:
@@ -1124,6 +1130,15 @@ class HTTPConnection:
             raise InvalidURL("URL can't contain control characters. {!r} ".format(host) +
                              "(found at least {!r})".format(match.group()))
 
+    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(
+                "method can't contain control characters. %r (found at "
+                "least %r)" % (method, match.group()))
+
     def putheader(self, header, *values):
         """Send a request header line to the server.
 
Index: Python-3.4.10/Lib/test/test_httplib.py
===================================================================
--- Python-3.4.10.orig/Lib/test/test_httplib.py
+++ Python-3.4.10/Lib/test/test_httplib.py
@@ -1223,12 +1223,33 @@ class TunnelTests(TestCase):
         self.assertIn(b'Host: destination.com', self.conn.sock.data)
 
 
+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="/")
+
 
 @support.reap_threads
 def test_main(verbose=None):
     support.run_unittest(HeaderTests, OfflineTest, BasicTest, TimeoutTest,
                          HTTPSTest, RequestBodyTest, SourceAddressTest,
-                         HTTPResponseTest, TunnelTests)
+                         HTTPResponseTest, TunnelTests, HttpMethodTests)
 
 if __name__ == '__main__':
     test_main()