[refactor] cleaning up uncloud_net for Wireguardvpn

uncloud_net/services.py

@@ -0,0 +1,118 @@
+from django.db import transaction
+from .models import *
+
+@transaction.atomic
+def create_vpn(*,
+               public_key: str,
+               network_size: int
+               ) -> VPNNetwork:
+
+    # Select suitable pool
+    pools = VPNPool.objects.filter(subnetwork_size=network_size)
+
+    # FIXME: exception - which?
+    if not pools:
+        return None
+
+
+
+    # Find all pools with the correct size
+
+    # For each pool see if it has still space:
+    # num network reversations < 2**(subnetwork_size-network_size)
+
+
+    def next_free_network(self):
+        if self.num_free_networks == 0:
+            # FIXME: use right exception
+            raise Exception("No free networks")
+
+        if len(self.free_networks) > 0:
+            return self.free_networks[0].address
+
+        if len(self.used_networks) > 0:
+            """
+            sample:
+
+            pool = 2a0a:e5c1:200::/40
+            last_used = 2a0a:e5c1:204::/48
+
+            next:
+            """
+
+            last_net = ipaddress.ip_network(self.used_networks.last().address)
+            last_net_ip = last_net[0]
+
+            if last_net_ip.version == 6:
+                offset_to_next = 2**(128 - self.subnetwork_size)
+            elif last_net_ip.version == 4:
+                offset_to_next = 2**(32 - self.subnetwork_size)
+
+            next_net_ip = last_net_ip + offset_to_next
+
+            return str(next_net_ip)
+        else:
+            # first network to be created
+            return self.network
+
+    @property
+    def wireguard_config_filename(self):
+        return '/etc/wireguard/{}.conf'.format(self.network)
+
+    @property
+    def wireguard_config(self):
+        wireguard_config = [
+            """
+[Interface]
+ListenPort = 51820
+PrivateKey = {privatekey}
+""".format(privatekey=self.wireguard_private_key) ]
+
+        peers = []
+
+        for reservation in self.vpnnetworkreservation_set.filter(status='used'):
+            public_key = reservation.vpnnetwork_set.first().wireguard_public_key
+            peer_network = "{}/{}".format(reservation.address, self.subnetwork_size)
+            owner = reservation.vpnnetwork_set.first().owner
+
+            peers.append("""
+# Owner: {owner}
+[Peer]
+PublicKey = {public_key}
+AllowedIPs = {peer_network}
+""".format(
+    owner=owner,
+    public_key=public_key,
+    peer_network=peer_network))
+
+        wireguard_config.extend(peers)
+
+        return "\n".join(wireguard_config)
+
+
+    def configure_wireguard_vpnserver(self):
+        """
+        This method is designed to run as a celery task and should
+        not be called directly from the web
+        """
+
+        # subprocess, ssh
+
+        pass
+
+
+
+    def num_maximum_networks(self):
+        """
+        sample:
+        network_size = 40
+        subnetwork_size = 48
+        maximum_networks = 2^(48-40)
+
+        2nd sample:
+        network_size = 8
+        subnetwork_size = 24
+        maximum_networks = 2^(24-8)
+        """
+
+        return 2**(self.subnetwork_mask - self.network_mask)