Add Server option KeepAliveDisable (keepalive_disable)

Signed-off-by: Joshua McBeth <joshua.mcbeth@gmail.com>

caddyconfig/httpcaddyfile/serveroptions.go

@@ -42,6 +42,7 @@ type serverOptions struct {
 	ReadHeaderTimeout    caddy.Duration
 	WriteTimeout         caddy.Duration
 	IdleTimeout          caddy.Duration
+	KeepAliveDisable     bool
 	KeepAliveInterval    caddy.Duration
 	KeepAliveIdle        caddy.Duration
 	KeepAliveCount       int
@@ -145,6 +146,13 @@ func unmarshalCaddyfileServerOptions(d *caddyfile.Dispenser) (any, error) {
 					return nil, d.Errf("unrecognized timeouts option '%s'", d.Val())
 				}
 			}
+
+		case "keepalive_disable":
+			if d.NextArg() {
+				return nil, d.ArgErr()
+			}
+			serverOpts.KeepAliveDisable = true
+
 		case "keepalive_interval":
 			if !d.NextArg() {
 				return nil, d.ArgErr()
@@ -331,6 +339,7 @@ func applyServerOptions(
 		server.ReadHeaderTimeout = opts.ReadHeaderTimeout
 		server.WriteTimeout = opts.WriteTimeout
 		server.IdleTimeout = opts.IdleTimeout
+		server.KeepAliveDisable = opts.KeepAliveDisable
 		server.KeepAliveInterval = opts.KeepAliveInterval
 		server.KeepAliveIdle = opts.KeepAliveIdle
 		server.KeepAliveCount = opts.KeepAliveCount

modules/caddyhttp/app.go

@@ -536,7 +536,7 @@ func (app *App) Start() error {
 					// create the listener for this socket
 					lnAny, err := listenAddr.Listen(app.ctx, portOffset, net.ListenConfig{
 						KeepAliveConfig: net.KeepAliveConfig{
-							Enable:   srv.KeepAliveInterval >= 0 || srv.KeepAliveIdle >= 0 || srv.KeepAliveCount >= 0,
+							Enable:   !srv.KeepAliveDisable,
 							Interval: time.Duration(srv.KeepAliveInterval),
 							Idle:     time.Duration(srv.KeepAliveIdle),
 							Count:    srv.KeepAliveCount,

modules/caddyhttp/server.go

@@ -74,18 +74,29 @@ type Server struct {
 	// 5m is applied to help avoid resource exhaustion.
 	IdleTimeout caddy.Duration `json:"idle_timeout,omitempty"`
 
+	// KeepAliveDsiable disables TCP keepalive packets.
+	// If set, the other TCP KeepAlive settings have no effect.
+	// KeepAlive is enabled by default.
+	KeepAliveDisable bool `json:"keepalive_disable,omitempty"`
+
 	// KeepAliveInterval is the interval at which TCP keepalive packets
 	// are sent to keep the connection alive at the TCP layer when no other
-	// data is being transmitted. The default is 15s.
+	// data is being transmitted.
+	// If zero, the default is 15s.
+	// If negative, underlying socket value is unchanged.
 	KeepAliveInterval caddy.Duration `json:"keepalive_interval,omitempty"`
 
 	// KeepAliveIdle is the time that the connection must be idle before
 	// the first TCP keep-alive probe is sent when no other data is being
-	// transmitted. The default is 15s.
+	// transmitted.
+	// If zero, the default is 15s.
+	// If negative, underlying socket value is unchanged.
 	KeepAliveIdle caddy.Duration `json:"keepalive_idle,omitempty"`
 
 	// KeepAliveCount is the maximum number of TCP keep-alive probes that
-	// should be sent before dropping a connection.  The default is 9.
+	// should be sent before dropping a connection.
+	// If zero, the default is 9.
+	// If negative, underlying socket value is unchanged.
 	KeepAliveCount int `json:"keepalive_count,omitempty"`
 
 	// MaxHeaderBytes is the maximum size to parse from a client's