netstack/stackopts: disable tcp opts

Author: ignoramous

intra/netstack/stackopts.go

@@ -7,6 +7,7 @@
 package netstack
 
 import (
+	"github.com/celzero/firestack/intra/settings"
 	"gvisor.dev/gvisor/pkg/tcpip"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
 	"gvisor.dev/gvisor/pkg/tcpip/network/ipv6"
@@ -15,40 +16,43 @@ import (
 )
 
 func SetNetstackOpts(s *stack.Stack) {
+	loopback := settings.Loopingback.Load()
 	// TODO: other stack otps?
 	// github.com/xjasonlyu/tun2socks/blob/31468620e/core/option/option.go#L69
 
 	// TODO: setup protocol opts?
 	// github.com/google/gvisor/blob/ef9e8d91/test/benchmarks/tcp/tcp_proxy.go#L233
-	sack := tcpip.TCPSACKEnabled(true)
+	sack := tcpip.TCPSACKEnabled(loopback)
 	_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &sack)
 
-	// from: github.com/telepresenceio/telepresence/blob/ab7dda7d55/pkg/vif/stack.go#L232
-	// Enable Receive Buffer Auto-Tuning, see: github.com/google/gvisor/issues/1666
-	bufauto := tcpip.TCPModerateReceiveBufferOption(true)
-	_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &bufauto)
-
-	// probably a bad idea? github.com/tailscale/tailscale/blob/9d9a70d81d/wgengine/netstack/netstack.go#L330
-	// coder.com/blog/delivering-5x-faster-throughput-in-coder-2-12-0
-	// ccopt := tcpip.CongestionControlOption("cubic")
-	// _ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &ccopt)
-
-	ttl := tcpip.DefaultTTLOption(128)
-	s.SetNetworkProtocolOption(ipv4.ProtocolNumber, &ttl)
-	s.SetNetworkProtocolOption(ipv6.ProtocolNumber, &ttl)
-
-	// github.com/tailscale/tailscale/blob/c4d0237e5c/wgengine/netstack/netstack_tcpbuf_default.go
-	tcpRXBufOpt := tcpip.TCPReceiveBufferSizeRangeOption{
-		Min:     tcp.MinBufferSize,
-		Default: tcp.DefaultSendBufferSize,
-		Max:     8 << 20, // 8MiB
+	if loopback {
+		// from: github.com/telepresenceio/telepresence/blob/ab7dda7d55/pkg/vif/stack.go#L232
+		// Enable Receive Buffer Auto-Tuning, see: github.com/google/gvisor/issues/1666
+		bufauto := tcpip.TCPModerateReceiveBufferOption(true)
+		_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &bufauto)
+
+		// probably a bad idea? github.com/tailscale/tailscale/blob/9d9a70d81d/wgengine/netstack/netstack.go#L330
+		// coder.com/blog/delivering-5x-faster-throughput-in-coder-2-12-0
+		// ccopt := tcpip.CongestionControlOption("cubic")
+		// _ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &ccopt)
+
+		ttl := tcpip.DefaultTTLOption(128)
+		s.SetNetworkProtocolOption(ipv4.ProtocolNumber, &ttl)
+		s.SetNetworkProtocolOption(ipv6.ProtocolNumber, &ttl)
+
+		// github.com/tailscale/tailscale/blob/c4d0237e5c/wgengine/netstack/netstack_tcpbuf_default.go
+		tcpRXBufOpt := tcpip.TCPReceiveBufferSizeRangeOption{
+			Min:     tcp.MinBufferSize,
+			Default: tcp.DefaultSendBufferSize,
+			Max:     8 << 20, // 8MiB
+		}
+		tcpTXBufOpt := tcpip.TCPSendBufferSizeRangeOption{
+			Min:     tcp.MinBufferSize,
+			Default: tcp.DefaultReceiveBufferSize,
+			Max:     6 << 20, // 6MiB
+		}
+		// github.com/tailscale/tailscale/blob/c4d0237e5c/wgengine/netstack/netstack.go#L329
+		_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &tcpRXBufOpt)
+		_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &tcpTXBufOpt)
 	}
-	tcpTXBufOpt := tcpip.TCPSendBufferSizeRangeOption{
-		Min:     tcp.MinBufferSize,
-		Default: tcp.DefaultReceiveBufferSize,
-		Max:     6 << 20, // 6MiB
-	}
-	// github.com/tailscale/tailscale/blob/c4d0237e5c/wgengine/netstack/netstack.go#L329
-	_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &tcpRXBufOpt)
-	_ = s.SetTransportProtocolOption(tcp.ProtocolNumber, &tcpTXBufOpt)
 }