File CVE-2024-41671.patch of Package python-Twisted.34943
Index: Twisted-19.10.0/src/twisted/web/http.py
===================================================================
--- Twisted-19.10.0.orig/src/twisted/web/http.py
+++ Twisted-19.10.0/src/twisted/web/http.py
@@ -1904,6 +1904,9 @@ class _ChunkedTransferDecoder(object):
self.finishCallback = finishCallback
self._buffer = bytearray()
self._start = 0
+ self._trailerHeaders = []
+ self._maxTrailerHeadersSize = 2**16
+ self._receivedTrailerHeadersSize = 0
def _dataReceived_CHUNK_LENGTH(self):
@@ -1964,19 +1967,43 @@ class _ChunkedTransferDecoder(object):
def _dataReceived_TRAILER(self):
- if len(self._buffer) < 2:
+ eolIndex = self._buffer.find(b"\r\n", self._start)
+
+ if eolIndex == -1:
+ # Still no end of network line marker found.
+ #
+ # Check if we've run up against the trailer size limit: if the next
+ # read contains the terminating CRLF then we'll have this many bytes
+ # of trailers (including the CRLFs).
+ minTrailerSize = (
+ self._receivedTrailerHeadersSize
+ + len(self._buffer)
+ + (1 if self._buffer.endswith(b"\r") else 2)
+ )
+ if minTrailerSize > self._maxTrailerHeadersSize:
+ raise _MalformedChunkedDataError("Trailer headers data is too long.")
+ # Continue processing more data.
return False
- if not self._buffer.startswith(b"\r\n"):
- raise _MalformedChunkedDataError("Chunk did not end with CRLF")
+ if eolIndex > 0:
+ # A trailer header was detected.
+ self._trailerHeaders.append(self._buffer[0:eolIndex])
+ del self._buffer[0 : eolIndex + 2]
+ self._start = 0
+ self._receivedTrailerHeadersSize += eolIndex + 2
+ if self._receivedTrailerHeadersSize > self._maxTrailerHeadersSize:
+ raise _MalformedChunkedDataError("Trailer headers data is too long.")
+ return True
+
+ # eolIndex in this part of code is equal to 0
data = memoryview(self._buffer)[2:].tobytes()
+
del self._buffer[:]
self.state = "FINISHED"
self.finishCallback(data)
return False
-
def _dataReceived_BODY(self):
if len(self._buffer) >= self.length:
chunk = memoryview(self._buffer)[: self.length].tobytes()
@@ -2287,8 +2314,8 @@ class HTTPChannel(basic.LineReceiver, po
def _finishRequestBody(self, data):
- self.allContentReceived()
self._dataBuffer.append(data)
+ self.allContentReceived()
def _maybeChooseTransferDecoder(self, header, data):
Index: Twisted-19.10.0/src/twisted/web/test/test_http.py
===================================================================
--- Twisted-19.10.0.orig/src/twisted/web/test/test_http.py
+++ Twisted-19.10.0/src/twisted/web/test/test_http.py
@@ -590,29 +590,41 @@ class PipeliningBodyTests(unittest.TestC
b"POST / HTTP/1.1\r\n"
b"Content-Length: 10\r\n"
b"\r\n"
- b"0123456789POST / HTTP/1.1\r\n"
- b"Content-Length: 10\r\n"
- b"\r\n"
b"0123456789"
+ # Chunk encoded request.
+ b"POST / HTTP/1.1\r\n"
+ b"Transfer-Encoding: chunked\r\n"
+ b"\r\n"
+ b"a\r\n"
+ b"0123456789\r\n"
+ b"0\r\n"
+ b"\r\n"
)
expectedResponses = [
- (b"HTTP/1.1 200 OK",
- b"Request: /",
- b"Command: POST",
- b"Version: HTTP/1.1",
- b"Content-Length: 21",
- b"'''\n10\n0123456789'''\n"),
- (b"HTTP/1.1 200 OK",
- b"Request: /",
- b"Command: POST",
- b"Version: HTTP/1.1",
- b"Content-Length: 21",
- b"'''\n10\n0123456789'''\n")]
-
- def test_noPipelining(self):
- """
- Test that pipelined requests get buffered, not processed in parallel.
+ (
+ b"HTTP/1.1 200 OK",
+ b"Request: /",
+ b"Command: POST",
+ b"Version: HTTP/1.1",
+ b"Content-Length: 21",
+ b"'''\n10\n0123456789'''\n",
+ ),
+ (
+ b"HTTP/1.1 200 OK",
+ b"Request: /",
+ b"Command: POST",
+ b"Version: HTTP/1.1",
+ b"Content-Length: 23",
+ b"'''\nNone\n0123456789'''\n",
+ ),
+ ]
+
+ def test_stepwiseTinyTube(self):
+ """
+ Imitate a slow connection that delivers one byte at a time.
+ The request handler (L{DelayedHTTPHandler}) is puppeted to
+ step through the handling of each request.
"""
b = StringTransport()
a = http.HTTPChannel()
@@ -621,10 +633,9 @@ class PipeliningBodyTests(unittest.TestC
# one byte at a time, to stress it.
for byte in iterbytes(self.requests):
a.dataReceived(byte)
- value = b.value()
# So far only one request should have been dispatched.
- self.assertEqual(value, b'')
+ self.assertEqual(b.value(), b"")
self.assertEqual(1, len(a.requests))
# Now, process each request one at a time.
@@ -633,9 +644,95 @@ class PipeliningBodyTests(unittest.TestC
request = a.requests[0].original
request.delayedProcess()
- value = b.value()
- self.assertResponseEquals(value, self.expectedResponses)
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_stepwiseDumpTruck(self):
+ """
+ Imitate a fast connection where several pipelined
+ requests arrive in a single read. The request handler
+ (L{DelayedHTTPHandler}) is puppeted to step through the
+ handling of each request.
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DelayedHTTPHandlerProxy
+ a.makeConnection(b)
+
+ a.dataReceived(self.requests)
+
+ # So far only one request should have been dispatched.
+ self.assertEqual(b.value(), b"")
+ self.assertEqual(1, len(a.requests))
+
+ # Now, process each request one at a time.
+ while a.requests:
+ self.assertEqual(1, len(a.requests))
+ request = a.requests[0].original
+ request.delayedProcess()
+
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_immediateTinyTube(self):
+ """
+ Imitate a slow connection that delivers one byte at a time.
+
+ (L{DummyHTTPHandler}) immediately responds, but no more
+ than one
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DummyHTTPHandlerProxy # "sync"
+ a.makeConnection(b)
+
+ # one byte at a time, to stress it.
+ for byte in iterbytes(self.requests):
+ a.dataReceived(byte)
+ # There is never more than one request dispatched at a time:
+ self.assertLessEqual(len(a.requests), 1)
+
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_immediateDumpTruck(self):
+ """
+ Imitate a fast connection where several pipelined
+ requests arrive in a single read. The request handler
+ (L{DummyHTTPHandler}) immediately responds.
+
+ This doesn't check the at-most-one pending request
+ invariant but exercises otherwise uncovered code paths.
+ See GHSA-c8m8-j448-xjx7.
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DummyHTTPHandlerProxy
+ a.makeConnection(b)
+
+ # All bytes at once to ensure there's stuff to buffer.
+ a.dataReceived(self.requests)
+
+ self.assertResponseEquals(b.value(), self.expectedResponses)
+
+ def test_immediateABiggerTruck(self):
+ """
+ Imitate a fast connection where a so many pipelined
+ requests arrive in a single read that backpressure is indicated.
+ The request handler (L{DummyHTTPHandler}) immediately responds.
+
+ This doesn't check the at-most-one pending request
+ invariant but exercises otherwise uncovered code paths.
+ See GHSA-c8m8-j448-xjx7.
+
+ @see: L{http.HTTPChannel._optimisticEagerReadSize}
+ """
+ b = StringTransport()
+ a = http.HTTPChannel()
+ a.requestFactory = DummyHTTPHandlerProxy
+ a.makeConnection(b)
+
+ overLimitCount = a._optimisticEagerReadSize // len(self.requests) * 10
+ a.dataReceived(self.requests * overLimitCount)
+ self.assertResponseEquals(b.value(), self.expectedResponses * overLimitCount)
def test_pipeliningReadLimit(self):
"""
@@ -1414,6 +1511,83 @@ class ChunkedTransferEncodingTests(unitt
http._MalformedChunkedDataError, p.dataReceived, b"0x3\r\nabc\r\n"
)
+ def test_trailerHeaders(self):
+ """
+ L{_ChunkedTransferDecoder.dataReceived} decodes chunked-encoded data
+ and ignores trailer headers which come after the terminating zero-length
+ chunk.
+ """
+ L = []
+ finished = []
+ p = http._ChunkedTransferDecoder(L.append, finished.append)
+ p.dataReceived(b"3\r\nabc\r\n5\r\n12345\r\n")
+ p.dataReceived(
+ b"a\r\n0123456789\r\n0\r\nServer-Timing: total;dur=123.4\r\nExpires: Wed, 21 Oct 2015 07:28:00 GMT\r\n\r\n"
+ )
+ self.assertEqual(L, [b"abc", b"12345", b"0123456789"])
+ self.assertEqual(finished, [b""])
+ self.assertEqual(
+ p._trailerHeaders,
+ [
+ b"Server-Timing: total;dur=123.4",
+ b"Expires: Wed, 21 Oct 2015 07:28:00 GMT",
+ ],
+ )
+
+ def test_shortTrailerHeader(self):
+ """
+ L{_ChunkedTransferDecoder.dataReceived} decodes chunks of input with
+ tailer header broken up and delivered in multiple calls.
+ """
+ L = []
+ finished = []
+ p = http._ChunkedTransferDecoder(L.append, finished.append)
+ for s in iterbytes(
+ b"3\r\nabc\r\n5\r\n12345\r\n0\r\nServer-Timing: total;dur=123.4\r\n\r\n"
+ ):
+ p.dataReceived(s)
+ self.assertEqual(L, [b"a", b"b", b"c", b"1", b"2", b"3", b"4", b"5"])
+ self.assertEqual(finished, [b""])
+ self.assertEqual(p._trailerHeaders, [b"Server-Timing: total;dur=123.4"])
+
+ def test_tooLongTrailerHeader(self):
+ r"""
+ L{_ChunkedTransferDecoder.dataReceived} raises
+ L{_MalformedChunkedDataError} when the trailing headers data is too long.
+ """
+ p = http._ChunkedTransferDecoder(
+ lambda b: None,
+ lambda b: None, # pragma: nocov
+ )
+ p._maxTrailerHeadersSize = 10
+ self.assertRaises(
+ http._MalformedChunkedDataError,
+ p.dataReceived,
+ b"3\r\nabc\r\n0\r\nTotal-Trailer: header;greater-then=10\r\n\r\n",
+ )
+
+ def test_unfinishedTrailerHeader(self):
+ r"""
+ L{_ChunkedTransferDecoder.dataReceived} raises
+ L{_MalformedChunkedDataError} when the trailing headers data is too long
+ and doesn't have final CRLF characters.
+ """
+ p = http._ChunkedTransferDecoder(
+ lambda b: None,
+ lambda b: None, # pragma: nocov
+ )
+ p._maxTrailerHeadersSize = 10
+ # 9 bytes are received so far, in 2 packets.
+ # For now, all is ok.
+ p.dataReceived(b"3\r\nabc\r\n0\r\n01234567")
+ p.dataReceived(b"\r")
+ # Once the 10th byte is received, the processing fails.
+ self.assertRaises(
+ http._MalformedChunkedDataError,
+ p.dataReceived,
+ b"A",
+ )
+
class ChunkingTests(unittest.TestCase, ResponseTestMixin):
