tune vnc socket

3 files changed, 35 insertions, 3 deletions

diff --git a/kvmd/apps/__init__.py b/kvmd/apps/__init__.py
index a4264faf..64127355 100644
--- a/kvmd/apps/__init__.py
+++ b/kvmd/apps/__init__.py
@@ -356,6 +356,15 @@ def _get_config_scheme() -> Dict:
                 "host":        Option("::", type=valid_ip_or_host),
                 "port":        Option(5900, type=valid_port),
                 "max_clients": Option(10,   type=valid_int_f1),
+
+                "no_delay": Option(True, type=valid_bool),
+                "keepalive": {
+                    "enabled":  Option(True, type=valid_bool, unpack_as="keepalive_enabled"),
+                    "idle":     Option(10, type=(lambda arg: valid_number(arg, min=1, max=3600)), unpack_as="keepalive_idle"),
+                    "interval": Option(3, type=(lambda arg: valid_number(arg, min=1, max=60)), unpack_as="keepalive_interval"),
+                    "count":    Option(3, type=(lambda arg: valid_number(arg, min=1, max=10)), unpack_as="keepalive_count"),
+                },
+
                 "tls": {
                     "ciphers": Option("ALL:@SECLEVEL=0", type=valid_ssl_ciphers),
                     "timeout": Option(5.0, type=valid_float_f01),
diff --git a/kvmd/apps/vnc/__init__.py b/kvmd/apps/vnc/__init__.py
index aaf67740..923ac39a 100644
--- a/kvmd/apps/vnc/__init__.py
+++ b/kvmd/apps/vnc/__init__.py
@@ -50,6 +50,8 @@ def main(argv: Optional[List[str]]=None) -> None:
         port=config.server.port,
         max_clients=config.server.max_clients,
 
+        no_delay=config.server.no_delay,
+
         tls_ciphers=config.server.tls.ciphers,
         tls_timeout=config.server.tls.timeout,
 
@@ -65,4 +67,6 @@ def main(argv: Optional[List[str]]=None) -> None:
             **config.streamer._unpack(),
         ),
         vnc_auth_manager=VncAuthManager(**config.auth.vncauth._unpack()),
+
+        **config.server.keepalive._unpack(),
     ).run()
diff --git a/kvmd/apps/vnc/server.py b/kvmd/apps/vnc/server.py
index 73c9c148..55ff4e7c 100644
--- a/kvmd/apps/vnc/server.py
+++ b/kvmd/apps/vnc/server.py
@@ -285,12 +285,18 @@ class _Client(RfbClient):  # pylint: disable=too-many-instance-attributes
 
 # =====
 class VncServer:  # pylint: disable=too-many-instance-attributes
-    def __init__(  # pylint: disable=too-many-arguments
+    def __init__(  # pylint: disable=too-many-arguments,too-many-locals
         self,
         host: str,
         port: int,
         max_clients: int,
 
+        no_delay: bool,
+        keepalive_enabled: bool,
+        keepalive_idle: int,
+        keepalive_interval: int,
+        keepalive_count: int,
+
         tls_ciphers: str,
         tls_timeout: float,
 
@@ -318,6 +324,19 @@ class VncServer:  # pylint: disable=too-many-instance-attributes
             remote = rfb_format_remote(writer)
             logger.info("[entry] [%s]: Connected client", remote)
             try:
+                sock = writer.get_extra_info("socket")
+                if no_delay:
+                    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+                if keepalive_enabled:
+                    # https://www.tldp.org/HOWTO/html_single/TCP-Keepalive-HOWTO/#setsockopt
+                    # https://blog.cloudflare.com/when-tcp-sockets-refuse-to-die
+                    sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
+                    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPIDLE, keepalive_idle)
+                    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPINTVL, keepalive_interval)
+                    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPCNT, keepalive_count)
+                    timeout = (keepalive_idle + keepalive_interval * keepalive_count) * 1000  # Milliseconds
+                    sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_USER_TIMEOUT, timeout)
+
                 try:
                     async with kvmd.make_session("", "") as kvmd_session:
                         none_auth_only = await kvmd_session.auth.check()
@@ -357,8 +376,8 @@ class VncServer:  # pylint: disable=too-many-instance-attributes
             logger.info("Listening VNC on TCP [%s]:%d ...", self.__host, self.__port)
 
             with contextlib.closing(socket.socket(socket.AF_INET6, socket.SOCK_STREAM)) as sock:
-                sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, False)
-                sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, True)
+                sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 0)
+                sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
                 sock.bind((self.__host, self.__port))
 
                 server = loop.run_until_complete(asyncio.start_server(