wgctl/daemon/wgctl-monitor.py
Nuno Duque Nunes 8b47e55b4a feat: peer endpoint history tracking and resolution
- daemon: update_peer_history() tracks all endpoints per peer
- daemon: endpoint_index.json for O(1) IP -> peer name lookup
- daemon: poll_handshakes updates history on every cycle
- json_helper: peer_history_lookup() uses index, falls back to scan
- resolve::endpoint_parts: step 3 checks peer history index
- json.sh: json::peer_history_lookup wrapper
- resolve: mobile peer IPs now resolve to peer name via history
2026-05-26 15:51:53 +00:00

385 lines
12 KiB
Python
Executable file

#!/usr/bin/env python3
import subprocess
import threading
import json
import logging
import os
import signal
import sys
import time
from datetime import datetime, timezone
from pathlib import Path
from scapy.all import IP, UDP, sniff
# ============================================
# Config
# ============================================
WATCHLIST_FILE = Path("/etc/wireguard/.wgctl/daemon/watchlist.json")
EVENTS_LOG = Path("/etc/wireguard/.wgctl/daemon/events.log")
WG_INTERFACE = os.environ.get("WG_INTERFACE", "eth0")
WG_PORT = int(os.environ.get("WG_PORT", "51820"))
LOG_LEVEL = os.environ.get("LOG_LEVEL", "INFO")
WG_HANDSHAKE_CHECK_SEC = int(os.environ.get("WG_HANDSHAKE_CHECK_TIME_SEC", "300"))
WG_WG_INTERFACE = os.environ.get("WG_WG_INTERFACE", "wg0") # WireGuard interface, not capture interface
HS_CACHE_FILE = Path("/etc/wireguard/.wgctl/daemon/hs_cache.json")
ENDPOINT_CACHE_FILE = Path("/etc/wireguard/.wgctl/daemon/endpoint_cache.json")
PEER_HISTORY_DIR = Path("/etc/wireguard/.wgctl/peer-history")
ENDPOINT_INDEX_FILE = PEER_HISTORY_DIR / "endpoint_index.json"
# ============================================
# Logging
# ============================================
logging.basicConfig(
level=getattr(logging, LOG_LEVEL),
format="%(asctime)s [%(levelname)s] %(message)s",
handlers=[logging.StreamHandler(sys.stdout)]
)
log = logging.getLogger("wgctl-monitor")
# ============================================
# Watchlist
# ============================================
_watchlist: dict[str, str] = {}
_watchlist_mtime: float = 0.0
def load_watchlist() -> dict[str, str]:
global _watchlist, _watchlist_mtime
try:
mtime = WATCHLIST_FILE.stat().st_mtime
if mtime == _watchlist_mtime:
return _watchlist
with WATCHLIST_FILE.open() as f:
_watchlist = json.load(f)
_watchlist_mtime = mtime
log.debug(f"Watchlist reloaded: {len(_watchlist)} entries")
except Exception as e:
log.error(f"Failed to load watchlist: {e}")
return _watchlist
def is_watched(ip: str) -> str | None:
watchlist = load_watchlist()
return watchlist.get(ip)
# ============================================
# Endpoint Resolution
# ============================================
def get_endpoint(public_key: str) -> str | None:
try:
import subprocess
result = subprocess.run(
["wg", "show", WG_INTERFACE, "endpoints"],
capture_output=True, text=True
)
for line in result.stdout.splitlines():
parts = line.split()
if len(parts) == 2 and parts[0] == public_key:
# Return just the IP without port
return parts[1].rsplit(":", 1)[0]
except Exception as e:
log.debug(f"Failed to get endpoint: {e}")
return None
def get_client_public_key(client_name: str) -> str | None:
key_file = Path(f"/etc/wireguard/clients/{client_name}_public.key")
try:
return key_file.read_text().strip()
except Exception:
return None
# ============================================
# Event Logging
# ============================================
def log_event(ip: str, client: str, event: str, endpoint: str | None = None):
entry = {
"timestamp": datetime.now(timezone.utc).isoformat(),
"ip": ip,
"client": client,
"event": event,
}
# Update endpoint cache when we see a packet
cache_file = ENDPOINT_CACHE_FILE
try:
with open(cache_file) as f:
cache = json.load(f)
except:
cache = {}
cache[client] = ip
with open(cache_file, 'w') as f:
json.dump(cache, f, indent=2)
if endpoint:
entry["endpoint"] = endpoint
try:
with EVENTS_LOG.open("a") as f:
f.write(json.dumps(entry) + "\n")
log.debug(f"Event logged: {entry}")
except Exception as e:
log.error(f"Failed to write event: {e}")
# ============================================
# Handshake Poller
# ============================================
# Tracks last logged handshake ts per pubkey
_hs_last_logged: dict[str, int] = {}
def load_hs_cache():
try:
with HS_CACHE_FILE.open() as f:
return {k: int(v) for k, v in json.load(f).items()}
except Exception:
return {}
def save_hs_cache(cache):
try:
with HS_CACHE_FILE.open('w') as f:
json.dump(cache, f)
except Exception:
pass
def build_pubkey_to_name() -> dict[str, str]:
"""Build pubkey -> client name map from public key files."""
mapping = {}
clients_dir = Path("/etc/wireguard/clients")
for kf in clients_dir.glob("*_public.key"):
name = kf.stem.replace("_public", "")
try:
mapping[kf.read_text().strip()] = name
except Exception:
pass
return mapping
def poll_handshakes():
"""
Poll wg show latest-handshakes periodically.
Log a handshake event only when gap > WG_HANDSHAKE_CHECK_SEC (new session).
"""
global _hs_last_logged, _endpoint_index
_hs_last_logged = load_hs_cache()
_endpoint_index = load_endpoint_index()
pubkey_to_name = build_pubkey_to_name()
log.info(f"Handshake poller started — {len(pubkey_to_name)} peers, "
f"session threshold {WG_HANDSHAKE_CHECK_SEC}s")
log.info(f"Endpoint index loaded — {len(_endpoint_index)} known endpoints")
while True:
try:
result = subprocess.run(
["wg", "show", WG_WG_INTERFACE, "latest-handshakes"],
capture_output=True, text=True
)
for line in result.stdout.strip().splitlines():
parts = line.split()
if len(parts) != 2:
continue
pubkey, ts_str = parts
try:
ts = int(ts_str)
except ValueError:
continue
if ts == 0:
continue
client = pubkey_to_name.get(pubkey)
if not client:
continue
last = _hs_last_logged.get(pubkey, 0)
gap = ts - last
# Always update last seen
_hs_last_logged[pubkey] = ts
# Get endpoint
endpoint = get_endpoint(pubkey) or ''
if not endpoint:
try:
cache = json.loads(ENDPOINT_CACHE_FILE.read_text())
endpoint = cache.get(client, '')
except Exception:
pass
# Always update peer history + index
if endpoint:
update_peer_history(client, endpoint, ts)
if gap < WG_HANDSHAKE_CHECK_SEC:
continue # keepalive, skip
# New session — log it
entry = {
"timestamp": datetime.fromtimestamp(ts, tz=timezone.utc).isoformat(),
"ip": "",
"client": client,
"event": "handshake",
"endpoint": endpoint,
}
try:
with EVENTS_LOG.open("a") as f:
f.write(json.dumps(entry) + "\n")
log.info(f"New session: {client} from {endpoint}")
except Exception as e:
log.error(f"Failed to write handshake event: {e}")
log.debug(f"Gap for {client}: {gap}s (threshold: {WG_HANDSHAKE_CHECK_SEC}s)")
save_hs_cache(_hs_last_logged)
except Exception as e:
log.error(f"Handshake poll error: {e}")
time.sleep(WG_HANDSHAKE_CHECK_SEC // 2)
# ============================================
# Peer History
# ============================================
def load_endpoint_index() -> dict:
"""Load endpoint -> peer name index."""
try:
if ENDPOINT_INDEX_FILE.exists():
return json.loads(ENDPOINT_INDEX_FILE.read_text())
except Exception:
pass
return {}
def save_endpoint_index(index: dict):
"""Save endpoint -> peer name index."""
try:
PEER_HISTORY_DIR.mkdir(parents=True, exist_ok=True)
ENDPOINT_INDEX_FILE.write_text(json.dumps(index, indent=2))
except Exception as e:
log.error(f"Failed to save endpoint index: {e}")
# In-memory index — loaded once, updated on each new endpoint
_endpoint_index: dict = {}
def update_peer_history(client: str, endpoint: str, ts: int):
"""
Update peer endpoint history and endpoint index.
Called on every poll cycle to keep last_seen current.
"""
global _endpoint_index
if not endpoint:
return
try:
PEER_HISTORY_DIR.mkdir(parents=True, exist_ok=True)
history_file = PEER_HISTORY_DIR / f"{client}.json"
if history_file.exists():
try:
data = json.loads(history_file.read_text())
except Exception:
data = {"peer": client, "endpoints": {}}
else:
data = {"peer": client, "endpoints": {}}
ts_iso = datetime.fromtimestamp(ts, tz=timezone.utc).isoformat()
eps = data.setdefault("endpoints", {})
is_new = endpoint not in eps
if is_new:
eps[endpoint] = {
"first_seen": ts_iso,
"last_seen": ts_iso,
"count": 1
}
log.debug(f"New endpoint for {client}: {endpoint}")
# Update in-memory index and persist
_endpoint_index[endpoint] = client
save_endpoint_index(_endpoint_index)
else:
eps[endpoint]["last_seen"] = ts_iso
eps[endpoint]["count"] += 1
history_file.write_text(json.dumps(data, indent=2))
except Exception as e:
log.error(f"Failed to update peer history for {client}: {e}")
# ============================================
# Packet Handler
# ============================================
def handle_packet(pkt):
if not (IP in pkt and UDP in pkt):
return
# Only care about packets targeting WireGuard port
if pkt[UDP].dport != WG_PORT:
return
src_ip = pkt[IP].src
client = is_watched(src_ip)
if not client:
return
# Resolve real endpoint IP
public_key = get_client_public_key(client)
endpoint = None
if public_key:
endpoint = get_endpoint(public_key)
# If no endpoint from wg show, use packet source IP
if not endpoint:
endpoint = src_ip
log_event(src_ip, client, "attempt", endpoint)
log.info(f"Blocked attempt: {client} ({src_ip}) from endpoint {endpoint}")
# ============================================
# Signal Handling
# ============================================
def handle_signal(signum, frame):
log.info("Shutting down wgctl-monitor")
sys.exit(0)
signal.signal(signal.SIGTERM, handle_signal)
signal.signal(signal.SIGINT, handle_signal)
# ============================================
# Main
# ============================================
def main():
log.info(f"wgctl-monitor starting on interface {WG_INTERFACE} port {WG_PORT}")
if not WATCHLIST_FILE.exists():
log.error(f"Watchlist not found: {WATCHLIST_FILE}")
sys.exit(1)
load_watchlist()
log.info("Watchlist loaded, starting packet capture...")
# Start handshake poller in background thread
hs_thread = threading.Thread(target=poll_handshakes, daemon=True)
hs_thread.start()
sniff(
iface=WG_INTERFACE,
filter=f"udp port {WG_PORT}",
prn=handle_packet,
store=0
)
if __name__ == "__main__":
main()