feat: WinDHCPD — Windows-native DHCP server
Python 3 + Scapy DHCP server with: - Full DORA handshake (DISCOVER/OFFER/REQUEST/ACK) - Multi-scope support with DHCP relay - Static MAC-to-IP bindings - Lease persistence (JSON) with auto-prune - NACK for invalid requests - Flask web management panel (dark theme, live refresh) - Admin-privileged scapy sniff on UDP 67
This commit is contained in:
Your Name
+189
@@ -0,0 +1,189 @@
|
||||
"""Lease database: in-memory index + JSON persistence."""
|
||||
|
||||
from __future__ import annotations
|
||||
|
||||
import ipaddress
|
||||
import json
|
||||
import logging
|
||||
import os
|
||||
import time
|
||||
from dataclasses import dataclass, asdict, field
|
||||
from datetime import datetime, timezone
|
||||
from typing import Dict, List, Optional
|
||||
|
||||
log = logging.getLogger("dhcpd.lease")
|
||||
|
||||
|
||||
@dataclass
|
||||
class Lease:
|
||||
mac: str # "aa:bb:cc:dd:ee:ff"
|
||||
ip: str
|
||||
hostname: str = ""
|
||||
offered_at: float = 0.0
|
||||
acknowledged_at: float = 0.0
|
||||
expires_at: float = 0.0
|
||||
static: bool = False # True = from static binding
|
||||
xid: int = 0
|
||||
scope: str = ""
|
||||
|
||||
@property
|
||||
def is_expired(self) -> bool:
|
||||
return time.time() > self.expires_at
|
||||
|
||||
@property
|
||||
def is_active(self) -> bool:
|
||||
return self.expires_at > time.time()
|
||||
|
||||
def to_json(self) -> dict:
|
||||
return {
|
||||
"mac": self.mac,
|
||||
"ip": self.ip,
|
||||
"hostname": self.hostname,
|
||||
"offered_at": self.offered_at,
|
||||
"acknowledged_at": self.acknowledged_at,
|
||||
"expires_at": self.expires_at,
|
||||
"static": self.static,
|
||||
"scope": self.scope,
|
||||
}
|
||||
|
||||
|
||||
class LeaseDB:
|
||||
"""Thread-ish safe lease store. (Single-threaded server, no lock needed.)"""
|
||||
|
||||
def __init__(self, db_path: str = "leases.db"):
|
||||
self.db_path = db_path
|
||||
# mac -> Lease
|
||||
self.by_mac: Dict[str, Lease] = {}
|
||||
# ip -> mac
|
||||
self.by_ip: Dict[str, str] = {}
|
||||
self._load()
|
||||
|
||||
# ── persistence ──────────────────────────────────────────────────────
|
||||
|
||||
def _load(self) -> None:
|
||||
if not os.path.exists(self.db_path):
|
||||
return
|
||||
try:
|
||||
with open(self.db_path, "r", encoding="utf-8") as f:
|
||||
data = json.load(f)
|
||||
except (json.JSONDecodeError, OSError) as e:
|
||||
log.warning("Could not load lease DB: %s", e)
|
||||
return
|
||||
if isinstance(data, list):
|
||||
for rec in data:
|
||||
try:
|
||||
lease = Lease(**rec)
|
||||
if lease.is_active or lease.static:
|
||||
self._put(lease)
|
||||
except TypeError:
|
||||
continue
|
||||
log.info("Loaded %d leases from %s", len(self.by_mac), self.db_path)
|
||||
|
||||
def save(self) -> None:
|
||||
try:
|
||||
records = [l.to_json() for l in self.by_mac.values()]
|
||||
with open(self.db_path, "w", encoding="utf-8") as f:
|
||||
json.dump(records, f, indent=2)
|
||||
except OSError as e:
|
||||
log.error("Failed to save lease DB: %s", e)
|
||||
|
||||
# ── CRUD ─────────────────────────────────────────────────────────────
|
||||
|
||||
def _put(self, lease: Lease) -> None:
|
||||
# remove stale entry if any
|
||||
if lease.mac in self.by_mac:
|
||||
old = self.by_mac[lease.mac]
|
||||
if old.ip != lease.ip:
|
||||
self.by_ip.pop(old.ip, None)
|
||||
if lease.ip in self.by_ip:
|
||||
del self.by_mac[self.by_ip[lease.ip]]
|
||||
self.by_mac[lease.mac] = lease
|
||||
self.by_ip[lease.ip] = lease.mac
|
||||
|
||||
def find_by_mac(self, mac: str) -> Optional[Lease]:
|
||||
return self.by_mac.get(mac)
|
||||
|
||||
def find_by_ip(self, ip: str) -> Optional[Lease]:
|
||||
mac = self.by_ip.get(ip)
|
||||
if mac:
|
||||
return self.by_mac.get(mac)
|
||||
return None
|
||||
|
||||
def is_ip_taken(self, ip: str) -> bool:
|
||||
return ip in self.by_ip
|
||||
|
||||
def add(self, lease: Lease) -> Lease:
|
||||
self._put(lease)
|
||||
self.save()
|
||||
return lease
|
||||
|
||||
def release(self, mac: str) -> bool:
|
||||
if mac in self.by_mac:
|
||||
lease = self.by_mac[mac]
|
||||
self.by_ip.pop(lease.ip, None)
|
||||
del self.by_mac[mac]
|
||||
self.save()
|
||||
log.info("Released lease: %s -> %s", mac, lease.ip)
|
||||
return True
|
||||
return False
|
||||
|
||||
def extend(self, mac: str, new_expires: float) -> Optional[Lease]:
|
||||
lease = self.by_mac.get(mac)
|
||||
if lease:
|
||||
lease.expires_at = new_expires
|
||||
self.save()
|
||||
return lease
|
||||
return None
|
||||
|
||||
# ── allocation ───────────────────────────────────────────────────────
|
||||
|
||||
def allocate_next(
|
||||
self,
|
||||
start: str,
|
||||
end: str,
|
||||
mac: str,
|
||||
lease_seconds: int,
|
||||
xid: int = 0,
|
||||
hostname: str = "",
|
||||
scope: str = "",
|
||||
) -> Optional[Lease]:
|
||||
"""Walk from start_ip to end_ip, return the first free address."""
|
||||
now = time.time()
|
||||
a_start = ipaddress.ip_address(start)
|
||||
a_end = ipaddress.ip_address(end)
|
||||
cur = a_start
|
||||
while cur <= a_end:
|
||||
cand = str(cur)
|
||||
if not self.is_ip_taken(cand):
|
||||
lease = Lease(
|
||||
mac=mac,
|
||||
ip=cand,
|
||||
hostname=hostname,
|
||||
offered_at=now,
|
||||
expires_at=now + lease_seconds,
|
||||
xid=xid,
|
||||
scope=scope,
|
||||
)
|
||||
self.add(lease)
|
||||
return lease
|
||||
cur = cur + 1
|
||||
return None
|
||||
|
||||
def list_all(self) -> List[Lease]:
|
||||
return sorted(self.by_mac.values(), key=lambda l: l.ip)
|
||||
|
||||
def count(self) -> int:
|
||||
return len(self.by_mac)
|
||||
|
||||
def count_active(self) -> int:
|
||||
return sum(1 for l in self.by_mac.values() if l.is_active)
|
||||
|
||||
def prune_expired(self) -> int:
|
||||
"""Remove expired non-static leases. Returns count removed."""
|
||||
to_remove = [
|
||||
mac for mac, l in self.by_mac.items()
|
||||
if not l.static and l.is_expired
|
||||
]
|
||||
for mac in to_remove:
|
||||
self.release(mac)
|
||||
return len(to_remove)
|
||||
Reference in New Issue
Block a user