gns3-server/tests/controller/test_udp_link.py
YueGuobin 350f2b24e7
fix: UDP port allocation race causing link self-loop (one-way links)
PortManager.get_free_udp_port had an unguarded find-then-add sequence.
A link allocates both ends concurrently (asyncio.gather in
UDPLink._prepare -> two POST /ports/udp) and FastAPI runs the sync
route handler in a threadpool, so both threads could probe the same
'free' port before either recorded it — handing lport == rport to both
ends. uBridge sets SO_REUSEADDR on UDP NIO sockets, so the double bind
succeeds silently and the kernel delivers everything to the last-bound
socket: one node starves, the other echoes to itself.

Make every TCP/UDP allocate/reserve/release path atomic with an RLock,
and rebuild _link_data in UDPLink._prepare so reset() commits the fresh
port pair instead of re-sending the stale, already-released one.

Regression tests: threaded barrier allocation never returns duplicates
(red on the old code, UDP and TCP); reset() leaves exactly one mirrored
NIO pair per side with lport != rport (red on the old code).
2026-08-14 21:31:58 +08:00

520 lines
16 KiB
Python

#!/usr/bin/env python
#
# Copyright (C) 2020 GNS3 Technologies Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import pytest
from unittest.mock import MagicMock
from tests.utils import AsyncioMagicMock
from gns3server.controller.udp_link import UDPLink
from gns3server.controller.ports.ethernet_port import EthernetPort
from gns3server.controller.node import Node
from gns3server.controller.controller_error import ControllerError
@pytest.mark.asyncio
async def test_create(project):
compute1 = MagicMock()
compute2 = MagicMock()
node1 = Node(project, compute1, "node1", node_type="vpcs")
node1._ports = [EthernetPort("E0", 0, 0, 4)]
node2 = Node(project, compute2, "node2", node_type="vpcs")
node2._ports = [EthernetPort("E0", 0, 3, 1)]
async def subnet_callback(compute2):
"""
Fake subnet callback
"""
return ("192.168.1.1", "192.168.1.2")
compute1.get_ip_on_same_subnet.side_effect = subnet_callback
link = UDPLink(project)
await link.add_node(node1, 0, 4)
await link.update_filters({"delay": [10, 0]})
async def compute1_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 1024}
return response
async def compute2_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 2048}
return response
compute1.post.side_effect = compute1_callback
compute1.host = "example.com"
compute2.post.side_effect = compute2_callback
compute2.host = "example.org"
await link.add_node(node2, 3, 1)
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
"lport": 1024,
"rhost": "192.168.1.2",
"rport": 2048,
"type": "nio_udp",
"filters": {"delay": [10, 0]},
"markers": {},
"suspend": False,
}, timeout=120)
compute2.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/3/ports/1/nio".format(project.id, node2.id), data={
"lport": 2048,
"rhost": "192.168.1.1",
"rport": 1024,
"type": "nio_udp",
"filters": {},
"markers": {},
"suspend": False,
}, timeout=120)
@pytest.mark.asyncio
async def test_create_one_side_failure(project):
compute1 = MagicMock()
compute2 = MagicMock()
node1 = Node(project, compute1, "node1", node_type="vpcs")
node1._ports = [EthernetPort("E0", 0, 0, 4)]
node2 = Node(project, compute2, "node2", node_type="vpcs")
node2._ports = [EthernetPort("E0", 0, 3, 1)]
async def subnet_callback(compute2):
"""
Fake subnet callback
"""
return ("192.168.1.1", "192.168.1.2")
compute1.get_ip_on_same_subnet.side_effect = subnet_callback
link = UDPLink(project)
await link.add_node(node1, 0, 4)
async def compute1_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 1024}
return response
async def compute2_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 2048}
return response
elif "/adapters" in path:
raise ControllerError("Error when creating the NIO")
compute1.post.side_effect = compute1_callback
compute1.host = "example.com"
compute2.post.side_effect = compute2_callback
compute2.host = "example.org"
with pytest.raises(ControllerError):
await link.add_node(node2, 3, 1)
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
"lport": 1024,
"rhost": "192.168.1.2",
"rport": 2048,
"type": "nio_udp",
"filters": {},
"markers": {},
"suspend": False,
}, timeout=120)
compute2.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/3/ports/1/nio".format(project.id, node2.id), data={
"lport": 2048,
"rhost": "192.168.1.1",
"rport": 1024,
"type": "nio_udp",
"filters": {},
"markers": {},
"suspend": False,
}, timeout=120)
# The link creation has failed we rollback the nio
compute1.delete.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), timeout=120)
@pytest.mark.asyncio
async def test_delete(project):
compute1 = MagicMock()
compute2 = MagicMock()
node1 = Node(project, compute1, "node1", node_type="vpcs")
node1._ports = [EthernetPort("E0", 0, 0, 4)]
node2 = Node(project, compute2, "node2", node_type="vpcs")
node2._ports = [EthernetPort("E0", 0, 3, 1)]
link = UDPLink(project)
link.create = AsyncioMagicMock()
await link.add_node(node1, 0, 4)
await link.add_node(node2, 3, 1)
await link.delete()
compute1.delete.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), timeout=120)
compute2.delete.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/3/ports/1/nio".format(project.id, node2.id), timeout=120)
@pytest.mark.asyncio
async def test_reset(project):
"""
reset() re-creates the link on the same object: the fresh port pair must
replace the stale one instead of accumulating (the committed NIOs always
come from indices 0/1) — see docs/bugs/link-udp-self-loop.md.
"""
compute1 = MagicMock()
compute2 = MagicMock()
node1 = Node(project, compute1, "node1", node_type="vpcs")
node1._ports = [EthernetPort("E0", 0, 0, 4)]
node2 = Node(project, compute2, "node2", node_type="vpcs")
node2._ports = [EthernetPort("E0", 0, 3, 1)]
async def subnet_callback(compute2):
"""
Fake subnet callback
"""
return ("192.168.1.1", "192.168.1.2")
compute1.get_ip_on_same_subnet.side_effect = subnet_callback
# per-compute port sequences: first create -> 1024/2048, reset -> 4096/8192
node1_ports = iter([1024, 4096])
node2_ports = iter([2048, 8192])
async def compute1_callback(path, data={}, **kwargs):
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": next(node1_ports)}
return response
async def compute2_callback(path, data={}, **kwargs):
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": next(node2_ports)}
return response
compute1.post.side_effect = compute1_callback
compute1.host = "example.com"
compute2.post.side_effect = compute2_callback
compute2.host = "example.org"
link = UDPLink(project)
await link.add_node(node1, 0, 4)
await link.add_node(node2, 3, 1)
await link.reset()
# exactly one (fresh) NIO spec per side — no stale entries left behind
assert len(link.debug_link_data) == 2
assert link.debug_link_data[0]["lport"] == 4096
assert link.debug_link_data[0]["rport"] == 8192
assert link.debug_link_data[1]["lport"] == 8192
assert link.debug_link_data[1]["rport"] == 4096
# the self-loop invariant: an end's lport must never equal its rport
assert link.debug_link_data[0]["lport"] != link.debug_link_data[0]["rport"]
assert link.debug_link_data[1]["lport"] != link.debug_link_data[1]["rport"]
# the committed NIO carries the fresh pair, not the released one
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
"lport": 4096,
"rhost": "192.168.1.2",
"rport": 8192,
"type": "nio_udp",
"filters": {},
"markers": {},
"suspend": False,
}, timeout=120)
@pytest.mark.asyncio
async def test_choose_capture_side(project):
"""
The link capture should run on the optimal node
"""
compute1 = MagicMock()
compute2 = MagicMock()
compute2.id = "local"
# Capture should run on the local node
node_vpcs = Node(project, compute1, "node1", node_type="vpcs")
node_vpcs._status = "started"
node_vpcs._ports = [EthernetPort("E0", 0, 0, 4)]
node_iou = Node(project, compute2, "node2", node_type="iou")
node_iou._status = "started"
node_iou._ports = [EthernetPort("E0", 0, 3, 1)]
link = UDPLink(project)
link.create = AsyncioMagicMock()
await link.add_node(node_vpcs, 0, 4)
await link.add_node(node_iou, 3, 1)
assert link._choose_capture_side()["node"] == node_iou
# Capture should choose always running node
node_iou = Node(project, compute1, "node5", node_type="iou")
node_iou._status = "started"
node_iou._ports = [EthernetPort("E0", 0, 0, 4)]
node_switch = Node(project, compute1, "node6", node_type="ethernet_switch")
node_switch._status = "started"
node_switch._ports = [EthernetPort("E0", 0, 3, 1)]
link = UDPLink(project)
link.create = AsyncioMagicMock()
await link.add_node(node_iou, 0, 4)
await link.add_node(node_switch, 3, 1)
assert link._choose_capture_side()["node"] == node_switch
# Capture should raise error if node are not started
node_vpcs = Node(project, compute1, "node1", node_type="vpcs")
node_vpcs._ports = [EthernetPort("E0", 0, 0, 4)]
node_iou = Node(project, compute2, "node2", node_type="iou")
node_iou._ports = [EthernetPort("E0", 0, 3, 1)]
link = UDPLink(project)
link.create = AsyncioMagicMock()
await link.add_node(node_vpcs, 0, 4)
await link.add_node(node_iou, 3, 1)
with pytest.raises(ControllerError):
link._choose_capture_side()
# If you start a node you can capture on it
node_vpcs._status = "started"
assert link._choose_capture_side()["node"] == node_vpcs
@pytest.mark.asyncio
async def test_capture(project):
compute1 = MagicMock()
node_vpcs = Node(project, compute1, "V1", node_type="vpcs")
node_vpcs._status = "started"
node_vpcs._ports = [EthernetPort("E0", 0, 0, 4)]
node_iou = Node(project, compute1, "I1", node_type="iou")
node_iou._ports = [EthernetPort("E0", 0, 3, 1)]
link = UDPLink(project)
link.create = AsyncioMagicMock()
await link.add_node(node_vpcs, 0, 4)
await link.add_node(node_iou, 3, 1)
await link.start_capture()
assert link.capturing
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/capture/start".format(project.id, node_vpcs.id), data={
"capture_file_name": link.default_capture_file_name(),
"data_link_type": "DLT_EN10MB"
})
await link.stop_capture()
assert link.capturing is False
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/capture/stop".format(project.id, node_vpcs.id))
@pytest.mark.asyncio
async def test_node_updated(project):
"""
If a node stop when capturing we stop the capture
"""
compute1 = MagicMock()
node_vpcs = Node(project, compute1, "V1", node_type="vpcs")
node_vpcs._status = "started"
link = UDPLink(project)
link._capture_node = {"node": node_vpcs}
link.stop_capture = AsyncioMagicMock()
await link.node_updated(node_vpcs)
assert not link.stop_capture.called
node_vpcs._status = "stopped"
await link.node_updated(node_vpcs)
assert link.stop_capture.called
@pytest.mark.asyncio
async def test_update(project):
compute1 = MagicMock()
compute2 = MagicMock()
node1 = Node(project, compute1, "node1", node_type="vpcs")
node1._ports = [EthernetPort("E0", 0, 0, 4)]
node2 = Node(project, compute2, "node2", node_type="vpcs")
node2._ports = [EthernetPort("E0", 0, 3, 1)]
async def subnet_callback(compute2):
"""
Fake subnet callback
"""
return ("192.168.1.1", "192.168.1.2")
compute1.get_ip_on_same_subnet.side_effect = subnet_callback
link = UDPLink(project)
await link.add_node(node1, 0, 4)
await link.update_filters({"delay": [10, 0]})
async def compute1_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 1024}
return response
async def compute2_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 2048}
return response
compute1.post.side_effect = compute1_callback
compute1.host = "example.com"
compute2.post.side_effect = compute2_callback
compute2.host = "example.org"
await link.add_node(node2, 3, 1)
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
"lport": 1024,
"rhost": "192.168.1.2",
"rport": 2048,
"type": "nio_udp",
"suspend": False,
"markers": {},
"filters": {"delay": [10, 0]}
}, timeout=120)
compute2.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/3/ports/1/nio".format(project.id, node2.id), data={
"lport": 2048,
"rhost": "192.168.1.1",
"rport": 1024,
"type": "nio_udp",
"suspend": False,
"markers": {},
"filters": {}
}, timeout=120)
assert link.created
await link.update_filters({"frequency_drop": [5], "bpf": ["icmp[icmptype] == 8"]})
compute1.put.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
"lport": 1024,
"rhost": "192.168.1.2",
"rport": 2048,
"type": "nio_udp",
"suspend": False,
"markers": {},
"filters": {
"frequency_drop": [5],
"bpf": ["icmp[icmptype] == 8"]
}
}, timeout=120)
@pytest.mark.asyncio
async def test_update_suspend(project):
compute1 = MagicMock()
compute2 = MagicMock()
node1 = Node(project, compute1, "node1", node_type="vpcs")
node1._ports = [EthernetPort("E0", 0, 0, 4)]
node2 = Node(project, compute2, "node2", node_type="vpcs")
node2._ports = [EthernetPort("E0", 0, 3, 1)]
async def subnet_callback(compute2):
"""
Fake subnet callback
"""
return ("192.168.1.1", "192.168.1.2")
compute1.get_ip_on_same_subnet.side_effect = subnet_callback
link = UDPLink(project)
await link.add_node(node1, 0, 4)
await link.update_filters({"frequency_drop": [-1]})
await link.update_suspend(True)
async def compute1_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 1024}
return response
async def compute2_callback(path, data={}, **kwargs):
"""
Fake server
"""
if "/ports/udp" in path:
response = MagicMock()
response.json = {"udp_port": 2048}
return response
compute1.post.side_effect = compute1_callback
compute1.host = "example.com"
compute2.post.side_effect = compute2_callback
compute2.host = "example.org"
await link.add_node(node2, 3, 1)
compute1.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/0/ports/4/nio".format(project.id, node1.id), data={
"lport": 1024,
"rhost": "192.168.1.2",
"rport": 2048,
"type": "nio_udp",
"filters": {"frequency_drop": [-1]},
"markers": {},
"suspend": True
}, timeout=120)
compute2.post.assert_any_call("/projects/{}/vpcs/nodes/{}/adapters/3/ports/1/nio".format(project.id, node2.id), data={
"lport": 2048,
"rhost": "192.168.1.1",
"rport": 1024,
"type": "nio_udp",
"filters": {},
"markers": {},
"suspend": True
}, timeout=120)