@@ -151,6 +151,10 @@

# _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'}

@@ -1119,6 +1123,8 @@ def putrequest(self, method, url, skip_host=False,

else:

raise CannotSendRequest(self.__state)

self._validate_method(method)

# Save the method for use later in the response phase

self._method = method

@@ -1209,6 +1215,15 @@ def _encode_request(self, request):

# ASCII also helps prevent CVE-2019-9740.

return request.encode('ascii')

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 _validate_path(self, url):

"""Validate a url for putrequest."""

# Prevent CVE-2019-9740.

@@ -359,6 +359,28 @@ def test_headers_debuglevel(self):

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"

@@ -0,0 +1,2 @@

Prevent http header injection by rejecting control characters in

http.client.putrequest(...).