config.py

@@ -0,0 +1,124 @@
+import os
+from ipaddress import IPv4Address, IPv4Network
+from dataclasses import dataclass, InitVar
+
+@dataclass
+class Peer:
+    public_key: str
+    endpoint: str | None
+    allowed_ips: list = []
+    untranslated_networks: InitVar(str | None) = None
+    local_translated_range: InitVar(str)
+    wireguard_address: InitVar(str)
+
+    def __post_init__(self):
+        self.allowed_ips = [self.local_translated_range, wireguard_address]
+        if untranslated_networks != None:
+            self.allowed_ips.append(untranslated_networks)
+
+@dataclass
+class Network:
+    name: str
+    data: InitVar[dict]
+    local_range: IPv4Network | None = None
+    local_translated_range: IPv4Network | None = None
+    translation_dict: dict = {}
+    untranslation_dict: dict = {}
+    
+    def __post_init__(self, data)
+        local_range = IPv4Network(data.get("local_range"))
+        local_translated_range = IPv4Network(data.get(local_translated_range))
+        for (loc, trans) in zip(self.local_range, self.local_translated_range):
+            self.translation_dict[str(loc)] = str(trans)
+            self.untranslation_dict[str(trans)] = str(loc)
+
+@dataclass
+class DNSServer:
+    address: str
+    port: int
+    network: str
+    zone: str
+
+    def is_same_zone(self, qname):
+        return self.zone == qname[-len(self.zone)-1:-1]
+
+@dataclass
+class Config:
+    dns_timeout: int
+    local_network: str
+    listen_port: int
+    listen_address: str
+    private_key: str
+    wg_listen_port: int
+    default_dns_address: InitVar[str]
+    default_dns_port: InitVar[int]
+    data: InitVar[dict]
+    networks: dict = {}
+    default_dns: DNSServer | None = None
+    dns_servers: dict = {}
+    remote_networks: dict = {}
+    peers: list = []
+    local_wireguard_address: str = ""
+
+    def __post_init__(self, default_dns_address, default_dns_port, data):
+        default_dns = DNSServer(
+                default_dns_address,
+                default_dns_port,
+                None,
+                None
+        )
+
+        self.local_wireguard_address = self.data["networks"][self.local_network]["wireguard_address"]
+    
+        for (name, network) in data["network"]:
+            self.networks[name] = Network(
+                    name,
+                    network,
+                    
+            if name != self.local_network:
+                peers.append(Peer(
+                    public_key=network.get("public_key"),
+                    wg_endpoint=network.get("endpoint", None),
+                    wireguard_address=network.get("wireguard_address"),
+                    local_translated_range=network.get("local_translated_range"),
+                    untranslated_networks=network.get("untranslated_networks", None))))
+
+            for (zone, ip) in value["dns"]:
+                self.dns_servers[zone] = DNSServer(ip, 53, name, zone)
+
+        self.remote_networks = [self.networks[key] for key in config.networks.values() if key != config.local_network]
+
+
+    @classmethod
+    def load(cls, path):
+        with open(path, "rb") as f:
+            data = tomllib.load(f)
+        return cls(data,
+            local_networ=os.environ.get('LOCAL_NETWORK'),
+            dns_timeout=int(os.environ.get('DNS_TIMEOUT', 5)),
+            listen_port=int(os.environ.get('LISTEN_PORT', 53)),
+            listen_address=os.environ.get('LISTEN_ADDRESS', "0.0.0.0"),
+            default_dns_address=os.environ.get('DEFAULT_DNS_ADDRESS', '1.1.1.1'),
+            default_dns_port= os.environ.get('DEFAULT_DNS_PORT', '53'), 
+            private_key=os.environ.get('PRIVATE_KEY'),
+            wg_listen_port=os.environ.get('WG_LISTEN_PORT', 51820)
+        )
+
+    def dns_server(self, qname):
+        """Guess which DNS server call from the requested domain name"""
+        for dns in self.dns_servers.values():
+            if dns.is_same_zone(qname):
+                return dns
+        return self.default_dns
+
+    def translate(self, ip, network):
+        """Translate if required given ip from given network"""
+        if IPv4Address(ip) in self.networks[network].local_range:
+            return self.networks[network].translation_dict[ip]
+        return ip
+
+    def untranslate(self, ip, network):
+        """Give back the original ip from a translated one from given network"""
+        if IPv4Address(ip) in self.networks[network].local_translated_range:
+            return self.networks[network].untranslation_dict[ip]
+        return ip

dns.py

@@ -7,43 +7,26 @@ from dnslib.label import DNSLabel
 from dnslib.ranges import IP4
 
 class ProxyResolver(BaseResolver):
-    def __init__(self, default_address, default_port, timeout, config):
-        self.default_address = default_address
-        self.default_port = default_port
-        self.timeout = timeout
+    def __init__(self, config):
+        self.timeout = config.dns_timeout
         self.config = config
     
     def resolve(self, request, handler):
-        address = self.default_address
-        port = self.default_port
-
-        subnets = [
-                (name, net["local_range"], net["local_translated_range"], net["dns"])
-                for name, net
-                in self.config.data["network"].items()
-        ]
-        
         qname = DNSLabel(request.q.qname)
-        current_server = ()
-        for (net, sub, trans, dns) in subnets:
-            for serv in dns:
-                if serv == str(qname)[-len(serv)-1:-1]:
-                    if net == self.config.local_network:
-                        current_server = {"sub": sub, "trans": trans, "dns": dns[serv]}  
-                    else:
-                        current_server = {"sub": sub, "trans": trans, "dns": translate(dns[serv], sub, trans)}
-                    address = current_server["dns"]
+        dns = self.config.dns_server(str(qname))
 
         try:
-            proxy_r = request.send(address, port, timeout=self.timeout)
+            proxy_r = request.send(dns.address, dns.port, timeout=self.timeout)
             reply = DNSRecord.parse(proxy_r)
         except socket.timeout:
             reply = request.reply()
             reply.header.rcode = getattr(RCODE, 'NXDOMAIN')
-        if address != self.default_address and address not in self.config.data["network"][self.config.local_network]["dns"].values():
+            return reply
+
+        if dns.network != None and dns.network != config.local_network:
             for rr in reply.rr:
-                if address == current_server["dns"] and IPv4Address(rr.rdata) in IPv4Network(current_server["sub"]):
-                    rr.rdata.data = IPv4Address(translate(str(rr.rdata), current_server["sub"], current_server["trans"])).packed
+                rr.rdata.data = IPv4Address(config.translate(str(rr.rdata), network)).packed
+
         reply.set_header_qa()
         return reply
 
@@ -54,11 +37,17 @@ def translate(ip, untranslated_range, translated_range):
     return ip
 
 
-def run(config, default_dns="1.1.1.1", default_port=53, timeout=5, port=53, address="0.0.0.0"):
-    resolver = ProxyResolver(default_dns, default_port, timeout, config)
+def run(config):
+    resolver = ProxyResolver(config)
     handler = DNSHandler
     logger = DNSLogger("+request,+reply,+truncated,+error,-recv,-send,-data")
-    udp_server = DNSServer(resolver, port=5353, address="0.0.0.0", logger=logger, handler=handler)
+    udp_server = DNSServer(
+            resolver,
+            port=config.listen_port,
+            address=config.listen_address,
+            logger=logger,
+            handler=handler
+    )
     udp_server.start_thread()
 
     while udp_server.isAlive():

load.py

@@ -19,88 +19,49 @@ from ipaddress import IPv4Address, IPv4Network
 import tomllib
 import jinja2
 
+import dns
+from config import Config
 
-dry_run = False
-if dry_run:
-    run = print
-else:
-    run = os.system
-
-class Config:
-    def __init__(self, path):
-        with open(path, "rb") as f:
-            data = tomllib.load(f)
-        self.data = data
-        self.networks = data["network"].keys()
-        self.local_network = os.environ.get('LOCAL_NETWORK')
-        self.remote_networks = list(filter(lambda k: k != self.local_network, self.networks))
-
-        self.local_range = str(IPv4Network(data["network"][self.local_network]["local_range"]))
-        self.local_translated_range = str(IPv4Network(data["network"][self.local_network]["local_translated_range"]))
-        self.remote_ranges = [str(IPv4Network(data["network"][net]["local_translated_range"])) for net in self.remote_networks]
-
-        self.dns_servers = []
-        for net in self.networks:
-            for domain in data["network"][net]["dns"].keys():
-                self.dns_servers.append({
-                    "ip": data["network"][net]["dns"][domain],
-                    "domain": domain,
-                })
- 
-
-
-def load_firewall(config):
+def load_firewall(config, run):
     run("nft -f templates/rules.nft")
 
-    run(f"nft add element ip filter local_range {{ {config.local_range} }}")
-    run(f"nft add element ip filter local_translated_range {{ {config.local_translated_range} }}")
-    for net in config.remote_ranges:
+    run(f"nft add element ip filter local_range {{ {config.networks[config.local_network].local_range} }}")
+    run(f"nft add element ip filter local_translated_range {{ {config.networks[config.local_network].local_translated_range} }}")
+    for net in config.remote_networks:
         run(f"nft add element ip filter remote_range {{ {net} }}")
 
-    for (loc, trans) in zip(IPv4Network(config.local_range), IPv4Network(config.local_translated_range)):
+    for (loc, trans) in config.networks[config.local_network].translation_dict:
         run(f"nft add element ip filter ip_map_snat {{ {loc} : {trans} }}")
         run(f"nft add element ip filter ip_map_dnat {{ {trans} : {loc} }}")
 
 
-def load_wireguard(config):
+def load_wireguard(config, run):
     with open("templates/wg-pn.conf.j2", "r") as f:
         env = jinja2.Environment()
         template = env.from_string(f.read())
 
-    peers = []
-
-
-    for net in config.remote_networks:
-        peer = {
-            "public_key": config.data["network"][net]["public_key"],
-        }
-
-        endpoint = config.data["network"][net].get("endpoint", "")
-        if endpoint != "":
-            peer["endpoint"] = endpoint
-        
-
-        peer["allowed_ips"] = config.data["network"][net]["local_translated_range"] + ", " + config.data["network"][net]["wireguard_address"]
-        untranslated_networks = config.data["network"][net].get("untranslated_networks", "")
-        if untranslated_networks != "":
-            peer["allowed_ips"] += ", " + untranslated_networks
-
-
-        peers.append(peer)
-
-
     with open("wg-pn.conf", "w") as f:
         f.write(template.render(
-            private_key=os.environ.get('PRIVATE_KEY'),
-            listen_port=os.environ.get('LISTEN_PORT', "51820"),
-            wireguard_address=config.data["network"][config.local_network]["wireguard_address"],
+            private_key=config.private_key,
+            listen_port=config.wg_listen_port,
+            wireguard_address=config.local_wireguard_address,
             peers=peers
         ))
 
-config = Config("/config/config.toml")
-load_firewall(config)
-load_wireguard(config)
 
-run("wg-quick up ./wg-pn.conf")
-import dns
-dns.run(config, port=5353)
+def main():
+    dry_run = False
+    if dry_run:
+        run = print
+    else:
+        run = os.system
+
+    config = Config("/config/config.toml")
+    load_firewall(config, run)
+    load_wireguard(config, run)
+
+    run("wg-quick up ./wg-pn.conf")
+    dns.run(config, port=5353)
+
+if __name__ == "__main__":
+    main()

templates/wg-pn.conf.j2

@@ -9,6 +9,6 @@ PublicKey = {{ peer.public_key }}
 {%- if peer.endpoint is defined %}
 Endpoint = {{ peer.endpoint }}
 {%- endif %}
-AllowedIPs = {{ peer.allowed_ips}}
+AllowedIPs = {{ peer.allowed_ips | join(', ') }}
 PersistentKeepalive = 25
-{% endfor %}
+{% endfor %}