bpo-37228: Fix loop.create_datagram_endpoint()'s usage of SO_REUSEADDR (#17311)
diff --git a/Lib/asyncio/base_events.py b/Lib/asyncio/base_events.py
index 0310712..adcdec1 100644
--- a/Lib/asyncio/base_events.py
+++ b/Lib/asyncio/base_events.py
@@ -66,6 +66,10 @@
# Maximum timeout passed to select to avoid OS limitations
MAXIMUM_SELECT_TIMEOUT = 24 * 3600
+# Used for deprecation and removal of `loop.create_datagram_endpoint()`'s
+# *reuse_address* parameter
+_unset = object()
+
def _format_handle(handle):
cb = handle._callback
@@ -1230,7 +1234,7 @@
async def create_datagram_endpoint(self, protocol_factory,
local_addr=None, remote_addr=None, *,
family=0, proto=0, flags=0,
- reuse_address=None, reuse_port=None,
+ reuse_address=_unset, reuse_port=None,
allow_broadcast=None, sock=None):
"""Create datagram connection."""
if sock is not None:
@@ -1239,7 +1243,7 @@
f'A UDP Socket was expected, got {sock!r}')
if (local_addr or remote_addr or
family or proto or flags or
- reuse_address or reuse_port or allow_broadcast):
+ reuse_port or allow_broadcast):
# show the problematic kwargs in exception msg
opts = dict(local_addr=local_addr, remote_addr=remote_addr,
family=family, proto=proto, flags=flags,
@@ -1306,8 +1310,18 @@
exceptions = []
- if reuse_address is None:
- reuse_address = os.name == 'posix' and sys.platform != 'cygwin'
+ # bpo-37228
+ if reuse_address is not _unset:
+ if reuse_address:
+ raise ValueError("Passing `reuse_address=True` is no "
+ "longer supported, as the usage of "
+ "SO_REUSEPORT in UDP poses a significant "
+ "security concern.")
+ else:
+ warnings.warn("The *reuse_address* parameter has been "
+ "deprecated as of 3.5.10 and is scheduled "
+ "for removal in 3.11.", DeprecationWarning,
+ stacklevel=2)
for ((family, proto),
(local_address, remote_address)) in addr_pairs_info:
@@ -1316,9 +1330,6 @@
try:
sock = socket.socket(
family=family, type=socket.SOCK_DGRAM, proto=proto)
- if reuse_address:
- sock.setsockopt(
- socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
if reuse_port:
_set_reuseport(sock)
if allow_broadcast: