gns3-server/tests/e2e/test_iol_docker_kernel_datapath.py
YueGuobin 30cb7119e5
test(e2e): assert the L2-anchor spec's server-side guarantees
The spec's gns3-server alignment section promised three assertions the
suites never carried; they land in harness.py and run in every kernel
scenario (plus the relay controls' anchor checks):

- E.1 assert_pure_l2: anchors and bridges carry no L3 identity (addrgenmode
  none, no address in /proc/net/if_inet6, no ip -o -4 addr) -- the kernel
  scenarios' anchors and per-link/switch bridges, relay-mode anchors and
  the switch's relay TAPs alike (hardening is a creation-time property,
  not a datapath one);
- E.2 assert_idle_silence (Dynamips suite): guest interfaces shut to
  silence IOS's own CDP/keepalives, settle 2.5 s, then a 5 s window of
  zero traffic over both anchors and the per-link bridge;
- assert_forwarding: every attached port reports brport/state == 3 -- a
  bridge left DOWN keeps its ports disabled and forwards nothing, with no
  error anywhere; the assertion is the only signal.

harness.l2only_supported() probes a throwaway uBridge once (link l2only
against a nonexistent device: 208 = command present, 202-Unknown command
= old build); without the command the assertions skip -- the spec's
degradation contract, mirroring the tc-capability skip.

The first live run caught a fifth-creator gap: the switch's relay port
TAPs (minted implicitly by bridge add_nio_tap) carried a live fe80::.
Delivered uBridge-side per the spec (fb72758: the transient TAP is
hardened at creation, attaches untouched); the server needed no change,
and the relay-control E.1 check is that creator's end-to-end coverage.
2026-10-06 00:21:10 +08:00

266 lines
12 KiB
Python

#
# Copyright (C) 2026 GNS3 Technologies Inc.
#
# This program is free software and is redistributed under the same terms as gns3-server.
# See the LICENSE file for licensing information.
#
"""
Live end-to-end test for the IOL runner container's kernel datapath (pytest
marker ``e2e``): two real iol-xe containers (Cisco CML's iol-runner images,
the real IOS-XE CLI on PID 1 stdio), driven through the controller REST API
and their telnet consoles. The guest leg stays the runner's unix-socket pair
— the kernel datapath buys the *link segment*: anchor TAPs, a per-link Linux
bridge, kernel filters, suspend and capture.
* two containers on one compute report ``kernel_datapath`` when the compute's
uBridge has both the tap module and the swappable bridge TAP leg
(``ubridge_bridge_tap``); the anchors (``gx`` TAPs) exist from node start,
before any link — and the per-link bridge enslaves exactly the two of them;
* real ICMP crosses the [unix ↔ TAP] port bridge relay;
* a ``delay 100`` filter lands as netem on both anchors, RTT grows ~200 ms;
* suspend admin-downs the anchor and kills the traffic; resume restores;
* link delete releases the port bridge's TAP leg (stop → delete_nio_tap) and
the anchor survives — re-creating the link swaps the leg back in (the
c-socket binding never re-binds) and the traffic returns;
* node stop tears the anchors down (uBridge holds their fds — port bridges
first, then tap delete); a restart recreates the whole wiring from the NIO;
* deleting the project leaves no anchors and no bridges behind.
``test_iol_docker_relay_control`` is the negative control on an isolated
relay-configured instance: the same topology rides unix ↔ UDP through the
uBridge relay (no anchors ever exist) and still pings.
"""
import re
import time
import pytest
from tests.e2e import harness
pytestmark = pytest.mark.e2e
# one adapter = one 4-port unit; Ethernet0/0 is (adapter 0, port 0)
ETH = (0, 0)
BOOT_TIMEOUT = 360
def _pick_image(server):
images = server.compute.docker_images()
image = next((name for name in images if name.startswith("iol-xe/iol-xe:")), None)
if not image:
pytest.skip(f"no iol-xe/iol-xe image available on this server (images: {images[:5]})")
return image
def _boot(server, project_id, node_id, timeout=BOOT_TIMEOUT):
node = server.compute.node(project_id, node_id)
console = harness.IOSConsole(node["console_host"], node["console"])
# straight_prompt: IOL boots from its NVRAM startup config straight into
# the CLI — no "Press RETURN" sentinel on this console
console.boot_wait(timeout=timeout, straight_prompt=True)
return console
def _topology(compute, pid, image, name):
n1 = compute.create_iol_router(pid, f"{name}-1", image)
n2 = compute.create_iol_router(pid, f"{name}-2", image)
return n1, n2
def test_iol_docker_kernel_datapath():
server = harness.live_server(kernel=True)
compute = server.compute
caps = compute.capabilities()
if caps.get("ubridge_bridge_tap") is not True or caps.get("ubridge_tap") is not True:
pytest.skip(
f"this compute's uBridge cannot serve the IOL container anchor lifecycle "
f"(ubridge_bridge_tap={caps.get('ubridge_bridge_tap')}, ubridge_tap={caps.get('ubridge_tap')})"
)
image = _pick_image(server)
harness.stage_iol_base_config(server)
project = compute.create_project("iol-e2e")
pid = project["project_id"]
a1 = a2 = None
try:
n1, n2 = _topology(compute, pid, image, "E2E")
n1_id, n2_id = n1["node_id"], n2["node_id"]
a1 = harness.iol_anchor_name(n1_id, *ETH)
a2 = harness.iol_anchor_name(n2_id, *ETH)
# The link is created while both containers are stopped: the kernel
# NIO is bound with no anchors in existence yet and wired by node
# start (the deferred-wiring path).
link = compute.create_link(pid, (n1_id, *ETH), (n2_id, *ETH))
lid = link["link_id"]
bridge = harness.link_bridge_name(lid)
assert link["kernel_datapath"] is True, link
assert not harness.tap_exists(a1), "anchors must not exist before start"
print(".. starting containers and waiting for IOS-XE boots")
compute.call("POST", f"/projects/{pid}/nodes/{n1_id}/start")
compute.call("POST", f"/projects/{pid}/nodes/{n2_id}/start")
c1 = _boot(server, pid, n1_id)
c2 = _boot(server, pid, n2_id)
# Kernel objects: anchors exist (born with the node, before the link
# was ever wired) and the per-link bridge has exactly the two of them.
assert harness.tap_exists(a1) and harness.tap_exists(a2), (a1, a2)
assert harness.bridge_members(bridge) == sorted([a1, a2]), harness.bridge_members(bridge)
# L2-anchor spec §E.1: anchors and the per-link bridge carry no L3
# identity (skipped on a uBridge without `link l2only`), and both
# ports are FORWARDING — the silent-failure guard.
if harness.l2only_supported():
harness.assert_pure_l2(a1)
harness.assert_pure_l2(a2)
harness.assert_pure_l2(bridge)
else:
print(".. uBridge without link l2only: skipping the §E.1 assertions")
harness.assert_forwarding(a1)
harness.assert_forwarding(a2)
harness.configure_ios(c1, "R1", eth_ip="10.1.1.1", eth_if="Ethernet0/0")
harness.configure_ios(c2, "R2", eth_ip="10.1.1.2", eth_if="Ethernet0/0")
out = c1.run("show ip int brief")
assert re.search(r"Ethernet0/0\s+10\.1\.1\.1\s+\S+\s+\S+\s+up\s+up", out), out
print(".. both routers configured, pinging through the port-bridge swap")
baseline = harness.wait_ping(c1, "10.1.1.2")
assert baseline["success"] == 100, baseline["raw"]
# delay 100: netem on both anchors (each impairs one direction),
# one-way ~100 ms => RTT grows by ~200 ms
compute.call("PUT", f"/projects/{pid}/links/{lid}", {"filters": {"delay": [100]}})
assert "netem" in harness.qdiscs(a1) and "netem" in harness.qdiscs(a2), (
harness.qdiscs(a1),
harness.qdiscs(a2),
)
delayed = harness.wait_ping(c1, "10.1.1.2")
assert delayed["success"] == 100, delayed["raw"]
assert delayed["avg"] >= 150, (baseline, delayed)
compute.call("PUT", f"/projects/{pid}/links/{lid}", {"filters": {}})
assert "netem" not in harness.qdiscs(a1), harness.qdiscs(a1)
fast = harness.wait_ping(c1, "10.1.1.2")
assert fast["success"] == 100 and fast["avg"] < 50, fast
# suspend: anchor admin-down (the port bridge's TAP writes fail EIO,
# nothing comes back); resume restores
compute.call("PUT", f"/projects/{pid}/links/{lid}", {"suspend": True})
assert not harness.tap_up(a1)
dead = harness.ping(c1, "10.1.1.2", repeat=3)
assert dead["success"] == 0, dead["raw"]
compute.call("PUT", f"/projects/{pid}/links/{lid}", {"suspend": False})
assert harness.tap_up(a1)
assert harness.wait_ping(c1, "10.1.1.2")["success"] == 100
# capture: AF_PACKET on the anchor writes a real pcap
capture = compute.call("POST", f"/projects/{pid}/links/{lid}/capture/start", {"data_link_type": "DLT_EN10MB"})
harness.ping(c1, "10.1.1.2")
time.sleep(1)
compute.call("POST", f"/projects/{pid}/links/{lid}/capture/stop")
path = capture["capture_file_path"]
count, ethertypes = harness.pcap_records(path)
assert count >= 4, f"{path}: {count} records"
assert "0800" in ethertypes, (path, ethertypes)
# delete / re-create the kernel link: the port bridge's TAP leg is
# released (stop -> delete_nio_tap), the anchor survives (the node
# owns it), and re-creating swaps the leg back in — the unix binding
# never re-binds across the churn.
compute.call("DELETE", f"/projects/{pid}/links/{lid}")
assert harness.bridge_members(bridge) is None
assert harness.tap_exists(a1) and harness.tap_exists(a2)
link = compute.create_link(pid, (n1_id, *ETH), (n2_id, *ETH))
lid = link["link_id"]
bridge = harness.link_bridge_name(lid)
assert link["kernel_datapath"] is True, link
assert harness.wait_ping(c1, "10.1.1.2", attempts=5)["success"] == 100
# node stop: uBridge holds the anchor fds, so the port bridges go
# first and the taps with them (a stopped container must not litter
# the host with gx devices); a restart recreates the whole wiring
# from the NIO that outlived it.
print(".. stopping and restarting container 1")
compute.call("POST", f"/projects/{pid}/nodes/{n1_id}/stop")
assert harness.wait_until(lambda: not harness.tap_exists(a1), timeout=15), a1
# the per-link bridge lost this end's port; it may be gone entirely
# (both endpoints delete it, last one wins)
assert harness.bridge_members(bridge) in (None, [a2]), harness.bridge_members(bridge)
compute.call("POST", f"/projects/{pid}/nodes/{n1_id}/start")
c1.close()
c1 = _boot(server, pid, n1_id)
assert harness.tap_exists(a1)
assert harness.bridge_members(bridge) == sorted([a1, a2]), harness.bridge_members(bridge)
harness.configure_ios(c1, "R1", eth_ip="10.1.1.1", eth_if="Ethernet0/0")
assert harness.wait_ping(c1, "10.1.1.2", attempts=5)["success"] == 100
c1.close()
c2.close()
except BaseException:
harness.release(server, pid, failed=True)
raise
harness.release(server, pid, failed=False)
# deleting the project closed the nodes: anchors and bridges go with them
assert harness.wait_until(lambda: not harness.tap_exists(a1) and not harness.tap_exists(a2), timeout=15), (
a1,
a2,
)
def test_iol_docker_relay_control():
"""
Negative control: the same topology with ``enable_kernel_datapath =
false`` (an isolated instance) wires nothing into the kernel — no
per-link bridge, no enslavement — and still pings over the unix ↔ UDP
relay.
Anchors DO exist here (an IOL container creates its port TAPs at start
whenever the uBridge tap module and the swappable leg are available);
the server configuration only decides whether links are attached to
them (the same semantics as QEMU's and Dynamips' anchors).
"""
server = harness.live_server(kernel=False)
compute = server.compute
image = _pick_image(server)
harness.stage_iol_base_config(server)
project = compute.create_project("iol-relay-e2e")
pid = project["project_id"]
n1_id = n2_id = a1 = None
try:
n1, n2 = _topology(compute, pid, image, "E2E")
n1_id, n2_id = n1["node_id"], n2["node_id"]
a1 = harness.iol_anchor_name(n1_id, *ETH)
link = compute.create_link(pid, (n1_id, *ETH), (n2_id, *ETH))
assert link["kernel_datapath"] is False, link
compute.call("POST", f"/projects/{pid}/nodes/{n1_id}/start")
compute.call("POST", f"/projects/{pid}/nodes/{n2_id}/start")
c1 = _boot(server, pid, n1_id)
c2 = _boot(server, pid, n2_id)
# no kernel wiring: the anchor (if born) is nobody's bridge port
assert harness.bridge_members(harness.link_bridge_name(link["link_id"])) is None
if harness.tap_exists(a1):
assert not harness.tap_up(a1), a1
if harness.l2only_supported():
# the L2 hardening is a creation-time property, not a
# datapath one: relay anchors are pure L2 too
harness.assert_pure_l2(a1)
harness.configure_ios(c1, "R1", eth_ip="10.1.1.1", eth_if="Ethernet0/0")
harness.configure_ios(c2, "R2", eth_ip="10.1.1.2", eth_if="Ethernet0/0")
relay_ping = harness.wait_ping(c1, "10.1.1.2")
assert relay_ping["success"] == 100, relay_ping["raw"]
c1.close()
c2.close()
except BaseException:
harness.release(server, pid, failed=True)
raise
harness.release(server, pid, failed=False)