unbound-dhcp-leases-bridge: Open a socket to listen for events

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/config/unbound/unbound-dhcp-leases-bridge b/config/unbound/unbound-dhcp-leases-bridge
index ba5cd822620d2baa74281ae875d50397a4b33fb8..d6b39bfc2bdd62d70ea244529aaaa0a5df6be479 100644 (file)
--- a/config/unbound/unbound-dhcp-leases-bridge
+++ b/config/unbound/unbound-dhcp-leases-bridge
@@ -30,6 +30,7 @@ import logging.handlers
 import os
 import re
 import signal
+import socket
 import stat
 import subprocess
 import sys
@@ -80,10 +81,11 @@ def reverse_pointer_to_ip_address(rr):
        return ".".join(parts)
 
 class UnboundDHCPLeasesBridge(object):
-       def __init__(self, dhcp_leases_file, fix_leases_file, unbound_leases_file, hosts_file):
+       def __init__(self, dhcp_leases_file, fix_leases_file, unbound_leases_file, hosts_file, socket_path):
                self.leases_file = dhcp_leases_file
                self.fix_leases_file = fix_leases_file
                self.hosts_file = hosts_file
+               self.socket_path = socket_path
 
                self.watches = {
                        self.leases_file     : inotify.constants.IN_MODIFY,
@@ -91,6 +93,8 @@ class UnboundDHCPLeasesBridge(object):
                        self.hosts_file      : 0,
                }
 
+               self.socket = None
+
                self.unbound = UnboundConfigWriter(unbound_leases_file)
                self.running = False
 
@@ -98,6 +102,9 @@ class UnboundDHCPLeasesBridge(object):
                log.info("Unbound DHCP Leases Bridge started on %s" % self.leases_file)
                self.running = True
 
+               # Open the server socket
+               self.socket = self._open_socket(self.socket_path)
+
                i = inotify.adapters.Inotify()
 
                # Add watches for the directories of every relevant file
@@ -113,6 +120,17 @@ class UnboundDHCPLeasesBridge(object):
                while self.running:
                        log.debug("Wakeup of main loop")
 
+                       # Accept any incoming connections
+                       try:
+                               conn, peer = self.socket.accept()
+                       except OSError as e:
+                               break
+
+                       # Receive what the client is sending
+                       data, ancillary_data, flags, address = conn.recvmsg(4096)
+
+                       log.error("Received message:\n%s" % data.decode())
+
                        # Process the entire inotify queue and identify what we need to do
                        for event in i.event_gen():
                                # Nothing to do
@@ -149,6 +167,29 @@ class UnboundDHCPLeasesBridge(object):
 
                log.info("Unbound DHCP Leases Bridge terminated")
 
+       def _open_socket(self, path):
+               # Allocate a new socket
+               s = socket.socket(family=socket.AF_UNIX, type=socket.SOCK_STREAM)
+
+               # Unlink any old sockets
+               try:
+                       os.unlink(path)
+               except FileNotFoundError as e:
+                       pass
+
+               # Bind the socket
+               try:
+                       s.bind(self.socket_path)
+               except OSError as e:
+                       log.error("Could not open socket at %s: %s" % (path, e))
+
+                       raise SystemExit(1) from e
+
+               # Listen
+               s.listen(128)
+
+               return s
+
        def update_dhcp_leases(self):
                leases = []
 
@@ -219,7 +260,11 @@ class UnboundDHCPLeasesBridge(object):
 
                return hosts
 
-       def terminate(self):
+       def terminate(self, *args, **kwargs):
+               # Close the socket
+               if self.socket:
+                       self.socket.close()
+
                self.running = False
 
 
@@ -588,6 +633,9 @@ if __name__ == "__main__":
                metavar="PATH", help="Path to the fix leases file")
        parser.add_argument("--hosts", default="/var/ipfire/main/hosts",
                metavar="PATH", help="Path to static hosts file")
+       parser.add_argument("--socket-path", default="/var/run/unbound-dhcp-leases-bridge.sock",
+               metavar="PATH", help="Socket Path",
+       )
 
        # Parse command line arguments
        args = parser.parse_args()
@@ -602,7 +650,7 @@ if __name__ == "__main__":
                        loglevel = logging.DEBUG
 
        bridge = UnboundDHCPLeasesBridge(args.dhcp_leases, args.fix_leases,
-               args.unbound_leases, args.hosts)
+               args.unbound_leases, args.hosts, socket_path=args.socket_path)
 
        with daemon.DaemonContext(
                detach_process=args.daemon,