YueGuobin d4b57d49fb
feat(docker): expose netem-extension packet filters on kernel links
Surface the netem extensions delivered in uBridge feature/tc-netem-ext
as GNS3 filter types: rate (tc-style bandwidth string), reorder (needs
delay), gemodel (Gilbert-Elliot bursty loss, exclusive with
packet_loss), duplicate, seed and limit, plus the delay jitter
distribution and the loss/dup correlation parameters. All are
kernel-datapath only — the relay's packet-filter registry has no
equivalent, so available_filters hides them on relay links, setting one
on a created relay link returns 409, and the project-load path drops
them with a warning (update_filters runs before the datapath is
decided, so it cannot reject there). Validation mirrors the tc grammar:
reorder requires delay, gemodel and packet_loss are mutually exclusive,
a distribution requires jitter > 0, rate is integer+unit capped at
100gbit.

The translation in DockerVM._netem_command_parts emits the frozen
grammar order and gates extension keywords on the 'tc capabilities'
netem token list (probed once per uBridge process; a plain
delay/loss/corrupt/dup filter never probes, keeping old uBridge builds
untouched; the correl suffix has no token and gates on 'rate' as the
extension-build marker).

Reconcile became reset-before-set: the kernel's netem change merges
optional attributes (rate, correlation, reorder, corrupt, gemodel,
distribution, seed keep their previous value when the new message omits
them), so removing a parameter needs an explicit 'tc reset' — the
bpf_drop filters are re-added right after in the same flow, so the
clsact churn is invisible. The capability check runs before the reset
so a failed update leaves the previous qdisc in place.

e2e (isolated instance, kernel link): 24/24 — rate 512kbit adds exactly
2x the per-packet serialization to the RTT (45.5 ms for 1400-byte
pings), paretonormal jitter + rate-cleared leak check, reorder gap 5,
gemodel 50% bursty loss, duplicate, loss 30% correl 50%, seed 42 +
limit 5000 visible in the qdisc dump, suspend/resume and node restart
keep the filters, relay link rejects rate with 409, teardown leaves no
netem. Full unit suite: 1916 passed.
2026-10-06 00:21:08 +08:00

145 lines
4.7 KiB
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/>.
from enum import Enum
from typing import List, Optional, Union
from pydantic import BaseModel, Field
class UDPNIOType(str, Enum):
udp = "nio_udp"
class UDPNIO(BaseModel):
"""
UDP Network Input/Output properties.
"""
type: UDPNIOType
lport: int = Field(..., gt=0, le=65535, description="Local port")
rhost: str = Field(..., description="Remote host")
rport: int = Field(..., gt=0, le=65535, description="Remote port")
suspend: Optional[bool] = Field(None, description="Suspend the NIO")
filters: Optional[dict] = Field(
None,
description="Packet filters (relay-supported types only: delay/packet_loss/corrupt/frequency_drop/bpf — "
"the netem extensions need a kernel-datapath NIO)",
)
markers: Optional[dict] = Field(None, description="Traffic-insight markers")
class EthernetNIOType(str, Enum):
ethernet = "nio_ethernet"
class EthernetNIO(BaseModel):
"""
Generic Ethernet Network Input/Output properties.
"""
type: EthernetNIOType
ethernet_device: str = Field(..., description="Ethernet device name e.g. eth0")
class TAPNIOType(str, Enum):
tap = "nio_tap"
class TAPNIO(BaseModel):
"""
TAP Network Input/Output properties.
"""
type: TAPNIOType
tap_device: str = Field(..., description="TAP device name e.g. tap0")
class BridgeNIOType(str, Enum):
bridge = "nio_bridge"
class BridgeNIO(BaseModel):
"""
Kernel-datapath bridge Network Input/Output properties. The NIO tells the
node to enslave its veth host end into the named kernel bridge instead of
wiring a uBridge UDP relay. Impairment filters run on the veth host end:
delay/packet_loss/corrupt and the netem extensions (rate, reorder,
gemodel, duplicate, seed, limit, jitter distributions, loss correlation)
as one tc netem qdisc, bpf as cls_bpf match-drop classifiers (needs a
uBridge reporting cbpf). frequency_drop still has no kernel equivalent
and is rejected. Markers and packet capture are served by uBridge's
AF_PACKET modules on the veth host end.
"""
type: BridgeNIOType
bridge: str = Field(..., description="Kernel bridge name e.g. gns3a1b2c3d4e5")
suspend: Optional[bool] = Field(None, description="Suspend the NIO")
filters: Optional[dict] = Field(
None,
description="Packet filters served on the veth host end (delay/packet_loss/corrupt and the netem extensions "
"via one tc netem qdisc, bpf via cls_bpf)",
)
markers: Optional[dict] = Field(None, description="Traffic-insight markers (attached to the veth host end)")
class MarkerToggle(BaseModel):
"""
Body for the per-marker enable/disable toggle endpoint: flips a running
uBridge marker filter with ``enable_packet_filter on|off`` (no NIO rebuild,
so the pcap identity and emitted counter are preserved).
"""
enabled: bool
class MarkerRebuild(BaseModel):
"""
Body for the per-marker rebuild endpoint: re-install a single uBridge marker
filter with new BPF/tag/direction via ``delete_packet_filter`` + add (NOT a
bridge-wide reset), so sibling markers keep their pcaps open. The marker's
own pcap is reopened by uBridge on re-add (new capture session for the new
BPF), which is expected.
"""
bpf: str
tag: Optional[int] = None
direction: Optional[str] = None
enabled: bool = True
link_id: str = ""
class BatchNIOEntry(BaseModel):
"""
A single NIO binding to create as part of a project-wide batch.
"""
node_id: str = Field(..., description="Node the NIO is attached to")
adapter_number: int = Field(0, ge=0, description="Adapter number")
port_number: int = Field(0, ge=0, description="Port number")
nio: Union[UDPNIO, BridgeNIO] = Field(..., description="NIO settings")
class BatchNIOCreate(BaseModel):
"""
Body for the project-wide batch NIO endpoint: create many NIO bindings in a
single request (used during project open) to avoid one HTTP round-trip per
NIO between controller and compute.
"""
nios: List[BatchNIOEntry] = Field(..., description="NIO bindings to create")