1 files changed, 79 insertions, 21 deletions
diff --git a/synapse/app/_base.py b/synapse/app/_base.py
index 18584226e9..3cbb003035 100644
--- a/synapse/app/_base.py
+++ b/synapse/app/_base.py
@@ -15,18 +15,35 @@
 
 import gc
 import logging
+import signal
 import sys
+import traceback
 
 import psutil
 from daemonize import Daemonize
 
 from twisted.internet import error, reactor
 
+from synapse.app import check_bind_error
+from synapse.crypto import context_factory
 from synapse.util import PreserveLoggingContext
 from synapse.util.rlimit import change_resource_limit
 
 logger = logging.getLogger(__name__)
 
+_sighup_callbacks = []
+
+
+def register_sighup(func):
+    """
+    Register a function to be called when a SIGHUP occurs.
+
+    Args:
+        func (function): Function to be called when sent a SIGHUP signal.
+            Will be called with a single argument, the homeserver.
+    """
+    _sighup_callbacks.append(func)
+
 
 def start_worker_reactor(appname, config):
     """ Run the reactor in the main process
@@ -143,6 +160,9 @@ def listen_metrics(bind_addresses, port):
 def listen_tcp(bind_addresses, port, factory, reactor=reactor, backlog=50):
     """
     Create a TCP socket for a port and several addresses
+
+    Returns:
+        list (empty)
     """
     for address in bind_addresses:
         try:
@@ -155,42 +175,80 @@ def listen_tcp(bind_addresses, port, factory, reactor=reactor, backlog=50):
         except error.CannotListenError as e:
             check_bind_error(e, address, bind_addresses)
 
+    logger.info("Synapse now listening on TCP port %d", port)
+    return []
+
 
 def listen_ssl(
     bind_addresses, port, factory, context_factory, reactor=reactor, backlog=50
 ):
     """
-    Create an SSL socket for a port and several addresses
+    Create an TLS-over-TCP socket for a port and several addresses
+
+    Returns:
+        list of twisted.internet.tcp.Port listening for TLS connections
     """
+    r = []
     for address in bind_addresses:
         try:
-            reactor.listenSSL(
-                port,
-                factory,
-                context_factory,
-                backlog,
-                address
+            r.append(
+                reactor.listenSSL(
+                    port,
+                    factory,
+                    context_factory,
+                    backlog,
+                    address
+                )
             )
         except error.CannotListenError as e:
             check_bind_error(e, address, bind_addresses)
 
+    logger.info("Synapse now listening on port %d (TLS)", port)
+    return r
+
 
-def check_bind_error(e, address, bind_addresses):
+def refresh_certificate(hs):
     """
-    This method checks an exception occurred while binding on 0.0.0.0.
-    If :: is specified in the bind addresses a warning is shown.
-    The exception is still raised otherwise.
+    Refresh the TLS certificates that Synapse is using by re-reading them from
+    disk and updating the TLS context factories to use them.
+    """
+    logging.info("Loading certificate from disk...")
+    hs.config.read_certificate_from_disk()
+    hs.tls_server_context_factory = context_factory.ServerContextFactory(hs.config)
+    hs.tls_client_options_factory = context_factory.ClientTLSOptionsFactory(
+        hs.config
+    )
+    logging.info("Certificate loaded.")
 
-    Binding on both 0.0.0.0 and :: causes an exception on Linux and macOS
-    because :: binds on both IPv4 and IPv6 (as per RFC 3493).
-    When binding on 0.0.0.0 after :: this can safely be ignored.
+
+def start(hs, listeners=None):
+    """
+    Start a Synapse server or worker.
 
     Args:
-        e (Exception): Exception that was caught.
-        address (str): Address on which binding was attempted.
-        bind_addresses (list): Addresses on which the service listens.
+        hs (synapse.server.HomeServer)
+        listeners (list[dict]): Listener configuration ('listeners' in homeserver.yaml)
     """
-    if address == '0.0.0.0' and '::' in bind_addresses:
-        logger.warn('Failed to listen on 0.0.0.0, continuing because listening on [::]')
-    else:
-        raise e
+    try:
+        # Set up the SIGHUP machinery.
+        if hasattr(signal, "SIGHUP"):
+            def handle_sighup(*args, **kwargs):
+                for i in _sighup_callbacks:
+                    i(hs)
+
+            signal.signal(signal.SIGHUP, handle_sighup)
+
+            register_sighup(refresh_certificate)
+
+        # Load the certificate from disk.
+        refresh_certificate(hs)
+
+        # It is now safe to start your Synapse.
+        hs.start_listening(listeners)
+        hs.get_datastore().start_profiling()
+    except Exception:
+        traceback.print_exc(file=sys.stderr)
+        reactor = hs.get_reactor()
+        if reactor.running:
+            reactor.stop()
+        sys.exit(1)