open-range / src /open_range /server /zone_router.py
Aaron Brown
Remove hardcoded infra, enforce snapshot-driven architecture
a24d0f2
"""Zone-based network routing enforcement.
Replaces iptables in the all-in-one container deployment.
All services run on localhost; this module enforces which
zones can reach which other zones on which ports.
The agent experiences identical training signal to a
multi-container setup with real iptables rules.
All routing data comes from the snapshot/manifest topology.
No hardcoded infrastructure constants.
"""
from __future__ import annotations
import logging
from dataclasses import dataclass, field
from typing import Any
logger = logging.getLogger(__name__)
@dataclass
class ZoneRouter:
"""Enforces network zone routing policy.
Must be constructed via ``from_snapshot()`` or ``from_manifest()``
to load topology-driven routes and host-zone mappings. The bare
constructor creates an empty (deny-all) router.
"""
routes: dict[tuple[str, str], set[int]] = field(default_factory=dict)
host_zones: dict[str, str] = field(default_factory=dict)
# ------------------------------------------------------------------ #
# Constructors
# ------------------------------------------------------------------ #
@classmethod
def from_snapshot(cls, topology: dict[str, Any]) -> "ZoneRouter":
"""Build router from snapshot topology and firewall rules.
This is the primary constructor. It reads ``hosts`` and
``firewall_rules`` from the topology dict to populate
``host_zones`` and ``routes``.
If ``firewall_rules`` is missing or empty, a permissive default
is generated: same-zone traffic is always allowed (handled by
``can_reach``), and all cross-zone traffic is denied.
If a host entry lacks a ``zone`` field, its zone is inferred as
``"unknown"``.
"""
router = cls()
# Build host_zones from topology hosts list
for host in topology.get("hosts", []):
if isinstance(host, dict):
name = host.get("name", "")
zone = host.get("zone", "unknown")
if name:
router.host_zones[name] = zone
elif isinstance(host, str):
# String-only entries get zone inferred as "unknown"
router.host_zones[host] = "unknown"
# Build routes from firewall_rules
rules = topology.get("firewall_rules", [])
if rules:
for rule in rules:
action = rule.get("action", "deny")
if action != "allow":
continue
from_z = rule.get("from_zone", rule.get("from", ""))
to_z = rule.get("to_zone", rule.get("to", ""))
ports = set(rule.get("ports", []))
if from_z and to_z:
key = (from_z, to_z)
router.routes[key] = router.routes.get(key, set()) | ports
# else: no firewall_rules → routes stays empty → cross-zone denied,
# same-zone allowed (handled by can_reach)
return router
@classmethod
def from_manifest(cls, manifest: dict[str, Any]) -> "ZoneRouter":
"""Build a ZoneRouter from a raw manifest dict.
Used during validation before a snapshot exists. Extracts
topology from the manifest and delegates to ``from_snapshot``.
"""
topology = manifest.get("topology", manifest)
return cls.from_snapshot(topology)
# ------------------------------------------------------------------ #
# Query methods
# ------------------------------------------------------------------ #
def can_reach(self, from_zone: str, to_zone: str, port: int) -> bool:
"""Check if a connection from one zone to another on a port is allowed."""
if from_zone == to_zone:
return True # same zone always allowed
allowed_ports = self.routes.get((from_zone, to_zone), set())
return port in allowed_ports
def get_zone(self, host: str) -> str:
"""Get the zone for a host."""
return self.host_zones.get(host, "unknown")
def check_command_access(self, from_host: str, target_host: str, port: int = 0) -> tuple[bool, str]:
"""Check if from_host can access target_host on port.
Returns (allowed, reason).
Unknown zones are denied (fail-closed).
"""
from_zone = self.get_zone(from_host)
to_zone = self.get_zone(target_host)
if from_zone == "unknown" or to_zone == "unknown":
unknown = from_zone if from_zone == "unknown" else to_zone
return False, f"unknown zone: {unknown}"
if self.can_reach(from_zone, to_zone, port):
logger.debug("ALLOW %s(%s) -> %s(%s):%d", from_host, from_zone, target_host, to_zone, port)
return True, "allowed"
else:
logger.info("BLOCK %s(%s) -> %s(%s):%d", from_host, from_zone, target_host, to_zone, port)
return False, f"Zone {from_zone} cannot reach {to_zone} on port {port}"