mirror of
https://github.com/GNS3/gns3-server.git
synced 2026-08-27 12:30:13 +03:00
3455da7da3
The host-side pass could not work for unprivileged GNS3 processes: the .gns3_perms marker is created root-owned by the container-side touch, and chowning root-owned files from the host requires root. Rewrite VendorDockerVM._fix_permissions to run the busybox record/chmod/chown script inside the container (as root) on the /gns3volumes bind-mount targets — they exist for the container's whole lifetime and do not depend on the mount --bind bridge, so a container restart can no longer make the fix hit the overlay copy. A stopped/exited container is skipped (logged) instead of restarted; the next start's pass fixes ownership.
399 lines
18 KiB
Python
399 lines
18 KiB
Python
#
|
||
# Copyright (C) 2025 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/>.
|
||
|
||
"""
|
||
Vendor NOS Docker container subclass.
|
||
|
||
Provides support for vendor NOS containers (Nokia SR Linux, Arista cEOS,
|
||
Juniper cRPD, …) whose CLI is a separate TUI process not exposed on PID 1
|
||
stdio, and whose boot model requires skipping GNS3's init.sh bootstrapping.
|
||
|
||
The subclass is selected automatically when ``console_type == "docker_exec"``.
|
||
All vendor features are opt-in — without GNS3_* environment variables the
|
||
container behaves identically to DockerVM.
|
||
"""
|
||
|
||
import asyncio
|
||
import json
|
||
import logging
|
||
import os
|
||
|
||
from gns3server.utils.asyncio.telnet_server import AsyncioTelnetServer
|
||
from gns3server.compute.docker.docker_vm import DockerVM
|
||
from gns3server.compute.docker.docker_error import DockerError, DockerHttp404Error
|
||
|
||
log = logging.getLogger(__name__)
|
||
|
||
|
||
class VendorDockerVM(DockerVM):
|
||
"""
|
||
DockerVM subclass for vendor NOS containers.
|
||
|
||
Opt-in features, activated by GNS3_-prefixed environment entries
|
||
(host-side only — GNS3_ entries are never forwarded into the container):
|
||
|
||
* ``GNS3_SKIP_INIT=1`` — do not prepend /gns3/init.sh; the container runs
|
||
its own entrypoint (e.g. SR Linux's ``sr_linux``). Init.sh's volume
|
||
persistence (bind-mount /gns3volumes → target) is replicated via
|
||
``docker exec`` after the container starts.
|
||
* ``GNS3_INTERFACE_NAMES=mgmt0,e1-1,e1-2`` — rename injected interfaces
|
||
(adapter order) instead of default ``eth{N}``.
|
||
* ``GNS3_CONSOLE_CMD=/opt/srlinux/bin/sr_cli`` — command run inside the
|
||
container by the ``docker_exec`` console (defaults to ``/bin/sh``).
|
||
"""
|
||
|
||
def __init__(self, *args, **kwargs):
|
||
super().__init__(*args, **kwargs)
|
||
|
||
# Prototype knobs — parsed from GNS3_-prefixed entries in create().
|
||
# Parse eagerly so _get_container_ifname can return the right name.
|
||
self._gns3_init = True
|
||
self._interface_names = []
|
||
self._console_cmd = None
|
||
self._console_exec_writer = None
|
||
|
||
if self._environment:
|
||
for _line in self._environment.splitlines():
|
||
_line = _line.strip().rstrip(",")
|
||
if _line.startswith("GNS3_SKIP_INIT="):
|
||
self._gns3_init = _line.split("=", 1)[1].strip().lower() not in ("1", "true", "yes")
|
||
elif _line.startswith("GNS3_INTERFACE_NAMES="):
|
||
self._interface_names = [
|
||
n.strip() for n in _line.split("=", 1)[1].split(",") if n.strip()
|
||
]
|
||
elif _line.startswith("GNS3_CONSOLE_CMD="):
|
||
self._console_cmd = _line.split("=", 1)[1].strip()
|
||
|
||
# ---- hook overrides ---------------------------------------------------
|
||
|
||
def _prepare_init_and_interface_env(self, params):
|
||
"""
|
||
Override: conditionally prepend init.sh, and honour
|
||
GNS3_INTERFACE_NAMES (if set) for GNS3_MAX_ETHERNET.
|
||
"""
|
||
if self._gns3_init:
|
||
params["Entrypoint"].insert(0, "/gns3/init.sh")
|
||
|
||
# Tell init.sh which last interface to wait for; honour the rename if any
|
||
# (no-op when init is skipped, but kept consistent).
|
||
if self._interface_names and self.adapters - 1 < len(self._interface_names):
|
||
last_ifname = self._interface_names[self.adapters - 1]
|
||
else:
|
||
last_ifname = f"eth{self.adapters - 1}"
|
||
params["Env"].append(f"GNS3_MAX_ETHERNET={last_ifname}")
|
||
|
||
def _get_container_ifname(self, adapter_number):
|
||
"""
|
||
Override: honour GNS3_INTERFACE_NAMES (e.g. mgmt0, e1-1) in adapter
|
||
order; fall back to eth{N} for unlisted ports.
|
||
"""
|
||
if self._interface_names and adapter_number < len(self._interface_names):
|
||
return self._interface_names[adapter_number]
|
||
return f"eth{adapter_number}"
|
||
|
||
def _cleanup_console_resources(self):
|
||
"""
|
||
Override: close the docker-exec pty socket, if any, so the next
|
||
restart or stop doesn't leak it.
|
||
"""
|
||
if self._console_exec_writer:
|
||
try:
|
||
self._console_exec_writer.close()
|
||
except Exception:
|
||
pass
|
||
self._console_exec_writer = None
|
||
|
||
async def start(self):
|
||
await super().start()
|
||
if self.status == "started" and not self._gns3_init:
|
||
await self._setup_skip_init_volumes()
|
||
# Fix host-side ownership of the seeded volume right away so the
|
||
# controller can read project files while the node runs. Reset the
|
||
# "fixed" flag afterwards: files written by the container during
|
||
# runtime still need the stop-time pass.
|
||
await self._fix_permissions()
|
||
self._permissions_fixed = False
|
||
|
||
async def _fix_permissions(self):
|
||
"""
|
||
Container-side override of DockerVM._fix_permissions for vendor NOS
|
||
containers. It targets the Docker bind-mount paths
|
||
(`/gns3volumes<volume>`) directly instead of the in-container paths:
|
||
the in-container paths only resolve to persistent storage while the
|
||
`mount --bind` bridge from _setup_skip_init_volumes is up, and after a
|
||
container restart the bridge is gone — the base implementation would
|
||
then chown the overlay copy instead of the host files.
|
||
|
||
The busybox script runs inside the container as root (a host-side
|
||
GNS3 process may be unprivileged and cannot chown root-owned files).
|
||
|
||
Unlike the base implementation, a stopped/exited container is NOT
|
||
restarted just to fix permissions (vendor NOS images are heavy to
|
||
boot): the pass is skipped and the next start fixes ownership.
|
||
"""
|
||
try:
|
||
state = await self._get_container_state()
|
||
except DockerHttp404Error:
|
||
log.warning("Container '%s' does not exist, skipping permission fix", self._name)
|
||
return
|
||
if state == "stopped" or state == "exited":
|
||
log.info(
|
||
"Container '%s' is %s, skipping permission fix (next start will fix)",
|
||
self._name, state,
|
||
)
|
||
return
|
||
|
||
uid, gid = os.getuid(), os.getgid()
|
||
for volume in self._volumes:
|
||
target = f"/gns3volumes{volume}"
|
||
log.debug("Docker container '%s' fix ownership on %s", self._name, target)
|
||
try:
|
||
process = await asyncio.subprocess.create_subprocess_exec(
|
||
"docker",
|
||
"exec",
|
||
self._cid,
|
||
"/gns3/bin/busybox",
|
||
"sh",
|
||
"-c",
|
||
"("
|
||
f'/gns3/bin/busybox find "{target}" -depth -print0'
|
||
f" | /gns3/bin/busybox xargs -0 /gns3/bin/busybox stat -c '%a:%u:%g:%n' > \"{target}/.gns3_perms\""
|
||
")"
|
||
f' && /gns3/bin/busybox chmod -R u+rX "{target}"'
|
||
f' && /gns3/bin/busybox chown {uid}:{gid} -R "{target}"',
|
||
stderr=asyncio.subprocess.PIPE,
|
||
)
|
||
except OSError as e:
|
||
raise DockerError(f"Could not fix permissions for {volume}: {e}")
|
||
await process.wait()
|
||
if process.returncode != 0:
|
||
stderr = (await process.stderr.read()).decode(errors="replace").strip()
|
||
log.error(
|
||
"Failed to fix permissions on '%s' for container '%s': %s",
|
||
volume, self._name, stderr or f"exit code {process.returncode}",
|
||
)
|
||
else:
|
||
self._permissions_fixed = True
|
||
|
||
async def _setup_skip_init_volumes(self):
|
||
"""
|
||
Replicate the volume-persistence portion of init.sh (lines 35–52) for
|
||
containers that skip init.sh (GNS3_SKIP_INIT=1).
|
||
|
||
On first start the container's original files are seeded into the
|
||
persistent host directory; on subsequent starts the persisted data
|
||
is bind-mounted over the in-container path so writes land on the host.
|
||
Permission-changes recorded by _fix_permissions at the previous
|
||
stop are restored (best-effort).
|
||
"""
|
||
for volume in self._volumes:
|
||
vol_target = f"/gns3volumes{volume}"
|
||
# fmt: off
|
||
script = (
|
||
f'mkdir -p "{volume}" && '
|
||
f'if [ ! -f "{vol_target}/.gns3_perms" ]; then '
|
||
f' /gns3/bin/busybox cp -a "{volume}/." "{vol_target}/" 2>/dev/null; '
|
||
f' /gns3/bin/busybox touch "{vol_target}/.gns3_perms"; '
|
||
f'fi && '
|
||
f'/gns3/bin/busybox mount --bind "{vol_target}" "{volume}" && '
|
||
f'while IFS=: read -r PERMS OWNER GROUP FILE; do '
|
||
f' [ -L "$FILE" ] || /gns3/bin/busybox chmod "$PERMS" "$FILE" 2>/dev/null; '
|
||
f' /gns3/bin/busybox chown -h "$OWNER:$GROUP" "$FILE" 2>/dev/null; '
|
||
f'done < "{volume}/.gns3_perms"'
|
||
)
|
||
# fmt: on
|
||
try:
|
||
process = await asyncio.subprocess.create_subprocess_exec(
|
||
"docker",
|
||
"exec",
|
||
self._cid,
|
||
"sh",
|
||
"-c",
|
||
script,
|
||
stdout=asyncio.subprocess.PIPE,
|
||
stderr=asyncio.subprocess.PIPE,
|
||
)
|
||
stdout, stderr = await process.communicate()
|
||
if process.returncode != 0:
|
||
err = stderr.decode(errors="replace").strip()
|
||
log.warning(
|
||
"Volume setup for '%s' on container '%s' returned %d: %s",
|
||
volume, self._name, process.returncode, err,
|
||
)
|
||
else:
|
||
log.info("Volume '%s' bound to persistent storage for '%s'", volume, self._name)
|
||
except OSError as e:
|
||
log.warning(
|
||
"Could not setup volume '%s' for container '%s': %s", volume, self._name, e
|
||
)
|
||
|
||
async def _start_console_server(self):
|
||
"""
|
||
Override: add the ``docker_exec`` console type alongside the
|
||
telnet/ssh/http types supported by the base class.
|
||
"""
|
||
if self.console_type == "docker_exec":
|
||
await self._start_docker_exec_console()
|
||
else:
|
||
await super()._start_console_server()
|
||
|
||
# ---- docker_exec console implementation --------------------------------
|
||
|
||
async def _start_docker_exec_console(self):
|
||
"""
|
||
Start a console that runs a command inside the container via the Docker
|
||
exec API, bridged to a telnet server. Intended for vendor NOS containers
|
||
(e.g. Nokia SR Linux) whose CLI is a separate TUI process not exposed on
|
||
PID 1's stdio.
|
||
|
||
The exec is created lazily on the first client connection (not when the
|
||
node starts) so the command's startup terminal probe has a real xterm.js
|
||
client to answer it (CPR / prompt_toolkit). The single exec is then
|
||
shared (broadcast) by all clients, matching GNS3's console model.
|
||
Command from GNS3_CONSOLE_CMD.
|
||
"""
|
||
|
||
command = self._console_cmd or "/bin/sh"
|
||
vm = self
|
||
manager = self.manager
|
||
cid = self._cid
|
||
|
||
class _LazyExecTelnetServer(AsyncioTelnetServer):
|
||
"""Telnet console whose docker exec (pty + command) is created on the
|
||
first client connection and then broadcast to all clients."""
|
||
|
||
def __init__(srv):
|
||
super().__init__(
|
||
reader=None,
|
||
writer=None,
|
||
binary=True,
|
||
echo=False,
|
||
naws=True,
|
||
window_size_changed_callback=srv._on_naws,
|
||
)
|
||
srv._exec_id = None
|
||
srv._started = False
|
||
srv._lock = asyncio.Lock()
|
||
srv._log_name = f"docker_exec console '{vm.name}'"
|
||
|
||
async def _on_naws(srv, columns, rows):
|
||
if srv._exec_id:
|
||
try:
|
||
await manager.query(
|
||
"POST",
|
||
f"exec/{srv._exec_id}/resize",
|
||
params={"h": str(rows), "w": str(columns)},
|
||
)
|
||
except DockerError:
|
||
pass
|
||
|
||
async def run(srv, network_reader, network_writer):
|
||
"""Catch and log any exception that kills the client session."""
|
||
try:
|
||
await super().run(network_reader, network_writer)
|
||
except Exception as exc:
|
||
log.warning(f"{srv._log_name}: client session terminated: {exc}", exc_info=True)
|
||
|
||
async def _create_exec(srv):
|
||
# create exec with a pty; run as root (vendor CLIs reject the
|
||
# image's default unprivileged user) and export TERM=xterm.
|
||
result = await manager.query(
|
||
"POST",
|
||
f"containers/{cid}/exec",
|
||
data={
|
||
"AttachStdin": True,
|
||
"AttachStdout": True,
|
||
"AttachStderr": True,
|
||
"Tty": True,
|
||
"User": "root",
|
||
"Env": ["TERM=xterm"],
|
||
"Cmd": ["sh", "-c", f"while true; do {command}; done"],
|
||
},
|
||
)
|
||
srv._exec_id = result["Id"]
|
||
log.info(f"{srv._log_name}: exec created ({srv._exec_id})")
|
||
|
||
# start the exec via a hijacked raw HTTP request on the Docker
|
||
# unix socket; with Tty:true the response body is a raw
|
||
# bidirectional pty byte stream (no multiplexing).
|
||
reader, writer = await asyncio.open_unix_connection(manager._server_url)
|
||
body = json.dumps({"Detach": False, "Tty": True})
|
||
request = (
|
||
f"POST /v{manager._api_version}/exec/{srv._exec_id}/start HTTP/1.1\r\n"
|
||
"Host: docker\r\n"
|
||
"Connection: Upgrade\r\n"
|
||
"Upgrade: tcp\r\n"
|
||
"Content-Type: application/json\r\n"
|
||
f"Content-Length: {len(body)}\r\n\r\n{body}"
|
||
).encode()
|
||
writer.write(request)
|
||
await writer.drain()
|
||
try:
|
||
headers = await asyncio.wait_for(reader.readuntil(b"\r\n\r\n"), timeout=5)
|
||
except (asyncio.IncompleteReadError, asyncio.TimeoutError) as e:
|
||
writer.close()
|
||
raise DockerError(f"Docker exec start failed: {e}")
|
||
status_line = headers.split(b"\r\n", 1)[0]
|
||
log.info(f"{srv._log_name}: hijacked start -> {status_line.decode(errors='ignore')}")
|
||
if b" 101 " not in status_line and b" 200 " not in status_line:
|
||
writer.close()
|
||
raise DockerError(f"Docker exec start rejected: {status_line.decode(errors='ignore')}")
|
||
|
||
# wire the exec stream as this server's upstream and start the
|
||
# broadcast task. AsyncioTelnetServer.start() only starts the
|
||
# broadcast when a reader is set at construction time, so with a
|
||
# lazy upstream we start it manually here.
|
||
srv._reader = reader
|
||
srv._writer = writer
|
||
vm._console_exec_writer = writer # for stop() cleanup
|
||
srv._broadcast_task = asyncio.create_task(srv._broadcast_from_upstream())
|
||
log.info(f"{srv._log_name}: broadcast task started, upstream wired, ready")
|
||
|
||
async def client_connected_hook(srv):
|
||
await super().client_connected_hook()
|
||
log.info(f"{srv._log_name}: client connected, lazy_started={srv._started}")
|
||
async with srv._lock:
|
||
if not srv._started:
|
||
try:
|
||
await srv._create_exec()
|
||
except Exception as exc:
|
||
log.warning(f"{srv._log_name}: failed to create exec: {exc}", exc_info=True)
|
||
raise
|
||
srv._started = True
|
||
try:
|
||
await srv._on_naws(80, 24) # initial size before NAWS
|
||
except Exception:
|
||
pass
|
||
# ask the TUI to (re)draw for the client that just connected.
|
||
if srv._writer:
|
||
try:
|
||
srv._writer.write(b"\x0c") # Ctrl-L -> TUI redraws
|
||
await srv._writer.drain()
|
||
except Exception as exc:
|
||
log.warning(f"{srv._log_name}: Ctrl-L write failed: {exc}")
|
||
log.info(f"{srv._log_name}: client_connected_hook done")
|
||
|
||
telnet = _LazyExecTelnetServer()
|
||
try:
|
||
self._telnet_servers.append(
|
||
await telnet.start(self._manager.port_manager.console_host, self.console)
|
||
)
|
||
except OSError as e:
|
||
raise DockerError(
|
||
f"Could not start console server on socket {self._manager.port_manager.console_host}:{self.console}: {e}"
|
||
)
|
||
log.debug(f"Docker container '{self.name}' started docker_exec console (lazy) on {self.console}")
|