Merge pull request #2435 from silkeh/listen-ipv6-default

Adapt the default config to bind on both IPv4 and IPv6 on all platforms

12 files changed, 247 insertions, 231 deletions

diff --git a/synapse/app/_base.py b/synapse/app/_base.py
index 9477737759..e4318cdfc3 100644
--- a/synapse/app/_base.py
+++ b/synapse/app/_base.py
@@ -25,7 +25,9 @@ except Exception:
 from daemonize import Daemonize
 from synapse.util import PreserveLoggingContext
 from synapse.util.rlimit import change_resource_limit
-from twisted.internet import reactor
+from twisted.internet import error, reactor
+
+logger = logging.getLogger(__name__)
 
 
 def start_worker_reactor(appname, config):
@@ -120,3 +122,57 @@ def quit_with_error(error_string):
         sys.stderr.write(" %s\n" % (line.rstrip(),))
     sys.stderr.write("*" * line_length + '\n')
     sys.exit(1)
+
+
+def listen_tcp(bind_addresses, port, factory, backlog=50):
+    """
+    Create a TCP socket for a port and several addresses
+    """
+    for address in bind_addresses:
+        try:
+            reactor.listenTCP(
+                port,
+                factory,
+                backlog,
+                address
+            )
+        except error.CannotListenError as e:
+            check_bind_error(e, address, bind_addresses)
+
+
+def listen_ssl(bind_addresses, port, factory, context_factory, backlog=50):
+    """
+    Create an SSL socket for a port and several addresses
+    """
+    for address in bind_addresses:
+        try:
+            reactor.listenSSL(
+                port,
+                factory,
+                context_factory,
+                backlog,
+                address
+            )
+        except error.CannotListenError as e:
+            check_bind_error(e, address, bind_addresses)
+
+
+def check_bind_error(e, address, bind_addresses):
+    """
+    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.
+
+    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.
+
+    Args:
+        e (Exception): Exception that was caught.
+        address (str): Address on which binding was attempted.
+        bind_addresses (list): Addresses on which the service listens.
+    """
+    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
diff --git a/synapse/app/appservice.py b/synapse/app/appservice.py
index ba2657bbad..7d0c2879ae 100644
--- a/synapse/app/appservice.py
+++ b/synapse/app/appservice.py
@@ -79,17 +79,16 @@ class AppserviceServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse appservice now listening on port %d", port)
 
@@ -98,18 +97,15 @@ class AppserviceServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/client_reader.py b/synapse/app/client_reader.py
index 129cfa901f..dc3f6efd43 100644
--- a/synapse/app/client_reader.py
+++ b/synapse/app/client_reader.py
@@ -103,17 +103,16 @@ class ClientReaderServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse client reader now listening on port %d", port)
 
@@ -122,18 +121,16 @@ class ClientReaderServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
+
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/federation_reader.py b/synapse/app/federation_reader.py
index 40cebe6f4a..a072291e1f 100644
--- a/synapse/app/federation_reader.py
+++ b/synapse/app/federation_reader.py
@@ -92,17 +92,16 @@ class FederationReaderServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse federation reader now listening on port %d", port)
 
@@ -111,18 +110,15 @@ class FederationReaderServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/federation_sender.py b/synapse/app/federation_sender.py
index 389e3909d1..09e9488f06 100644
--- a/synapse/app/federation_sender.py
+++ b/synapse/app/federation_sender.py
@@ -106,17 +106,16 @@ class FederationSenderServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse federation_sender now listening on port %d", port)
 
@@ -125,18 +124,15 @@ class FederationSenderServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/frontend_proxy.py b/synapse/app/frontend_proxy.py
index abc7ef5725..ae531c0aa4 100644
--- a/synapse/app/frontend_proxy.py
+++ b/synapse/app/frontend_proxy.py
@@ -157,17 +157,16 @@ class FrontendProxyServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse client reader now listening on port %d", port)
 
@@ -176,18 +175,15 @@ class FrontendProxyServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 6b8875afb4..92ab3b311b 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -25,7 +25,7 @@ from synapse.api.urls import CONTENT_REPO_PREFIX, FEDERATION_PREFIX, \
     LEGACY_MEDIA_PREFIX, MEDIA_PREFIX, SERVER_KEY_PREFIX, SERVER_KEY_V2_PREFIX, \
     STATIC_PREFIX, WEB_CLIENT_PREFIX
 from synapse.app import _base
-from synapse.app._base import quit_with_error
+from synapse.app._base import quit_with_error, listen_ssl, listen_tcp
 from synapse.config._base import ConfigError
 from synapse.config.homeserver import HomeServerConfig
 from synapse.crypto import context_factory
@@ -130,30 +130,29 @@ class SynapseHomeServer(HomeServer):
         root_resource = create_resource_tree(resources, root_resource)
 
         if tls:
-            for address in bind_addresses:
-                reactor.listenSSL(
-                    port,
-                    SynapseSite(
-                        "synapse.access.https.%s" % (site_tag,),
-                        site_tag,
-                        listener_config,
-                        root_resource,
-                    ),
-                    self.tls_server_context_factory,
-                    interface=address
-                )
+            listen_ssl(
+                bind_addresses,
+                port,
+                SynapseSite(
+                    "synapse.access.https.%s" % (site_tag,),
+                    site_tag,
+                    listener_config,
+                    root_resource,
+                ),
+                self.tls_server_context_factory,
+            )
+
         else:
-            for address in bind_addresses:
-                reactor.listenTCP(
-                    port,
-                    SynapseSite(
-                        "synapse.access.http.%s" % (site_tag,),
-                        site_tag,
-                        listener_config,
-                        root_resource,
-                    ),
-                    interface=address
+            listen_tcp(
+                bind_addresses,
+                port,
+                SynapseSite(
+                    "synapse.access.http.%s" % (site_tag,),
+                    site_tag,
+                    listener_config,
+                    root_resource,
                 )
+            )
         logger.info("Synapse now listening on port %d", port)
 
     def _configure_named_resource(self, name, compress=False):
@@ -229,18 +228,15 @@ class SynapseHomeServer(HomeServer):
             if listener["type"] == "http":
                 self._listener_http(config, listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             elif listener["type"] == "replication":
                 bind_addresses = listener["bind_addresses"]
                 for address in bind_addresses:
diff --git a/synapse/app/media_repository.py b/synapse/app/media_repository.py
index c4e5f0965d..eab1597aaa 100644
--- a/synapse/app/media_repository.py
+++ b/synapse/app/media_repository.py
@@ -99,17 +99,16 @@ class MediaRepositoryServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse media repository now listening on port %d", port)
 
@@ -118,18 +117,15 @@ class MediaRepositoryServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/pusher.py b/synapse/app/pusher.py
index db9a4d16f4..7fbbb0b0e1 100644
--- a/synapse/app/pusher.py
+++ b/synapse/app/pusher.py
@@ -114,17 +114,16 @@ class PusherServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse pusher now listening on port %d", port)
 
@@ -133,18 +132,15 @@ class PusherServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/synchrotron.py b/synapse/app/synchrotron.py
index 323fddee21..0abba3016e 100644
--- a/synapse/app/synchrotron.py
+++ b/synapse/app/synchrotron.py
@@ -288,17 +288,16 @@ class SynchrotronServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse synchrotron now listening on port %d", port)
 
@@ -307,18 +306,15 @@ class SynchrotronServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/app/user_dir.py b/synapse/app/user_dir.py
index be661a70c7..a48c4a2ae6 100644
--- a/synapse/app/user_dir.py
+++ b/synapse/app/user_dir.py
@@ -131,17 +131,16 @@ class UserDirectoryServer(HomeServer):
 
         root_resource = create_resource_tree(resources, Resource())
 
-        for address in bind_addresses:
-            reactor.listenTCP(
-                port,
-                SynapseSite(
-                    "synapse.access.http.%s" % (site_tag,),
-                    site_tag,
-                    listener_config,
-                    root_resource,
-                ),
-                interface=address
+        _base.listen_tcp(
+            bind_addresses,
+            port,
+            SynapseSite(
+                "synapse.access.http.%s" % (site_tag,),
+                site_tag,
+                listener_config,
+                root_resource,
             )
+        )
 
         logger.info("Synapse user_dir now listening on port %d", port)
 
@@ -150,18 +149,15 @@ class UserDirectoryServer(HomeServer):
             if listener["type"] == "http":
                 self._listen_http(listener)
             elif listener["type"] == "manhole":
-                bind_addresses = listener["bind_addresses"]
-
-                for address in bind_addresses:
-                    reactor.listenTCP(
-                        listener["port"],
-                        manhole(
-                            username="matrix",
-                            password="rabbithole",
-                            globals={"hs": self},
-                        ),
-                        interface=address
+                _base.listen_tcp(
+                    listener["bind_addresses"],
+                    listener["port"],
+                    manhole(
+                        username="matrix",
+                        password="rabbithole",
+                        globals={"hs": self},
                     )
+                )
             else:
                 logger.warn("Unrecognized listener type: %s", listener["type"])
 
diff --git a/synapse/config/server.py b/synapse/config/server.py
index edb90a1348..436dd8a6fe 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -220,13 +220,12 @@ class ServerConfig(Config):
             port: %(bind_port)s
 
             # Local addresses to listen on.
-            # This will listen on all IPv4 addresses by default.
+            # On Linux and Mac OS, `::` will listen on all IPv4 and IPv6
+            # addresses by default. For most other OSes, this will only listen
+            # on IPv6.
             bind_addresses:
+              - '::'
               - '0.0.0.0'
-              # Uncomment to listen on all IPv6 interfaces
-              # N.B: On at least Linux this will also listen on all IPv4
-              # addresses, so you will need to comment out the line above.
-              # - '::'
 
             # This is a 'http' listener, allows us to specify 'resources'.
             type: http
@@ -264,7 +263,7 @@ class ServerConfig(Config):
           # For when matrix traffic passes through loadbalancer that unwraps TLS.
           - port: %(unsecure_port)s
             tls: false
-            bind_addresses: ['0.0.0.0']
+            bind_addresses: ['::', '0.0.0.0']
             type: http
 
             x_forwarded: false
@@ -278,7 +277,7 @@ class ServerConfig(Config):
           # Turn on the twisted ssh manhole service on localhost on the given
           # port.
           # - port: 9000
-          #   bind_address: 127.0.0.1
+          #   bind_addresses: ['::1', '127.0.0.1']
           #   type: manhole
         """ % locals()