[WIP] Support Quality Transport

QTransport/swarm_QTransport.go

@@ -0,0 +1,127 @@
+package QTransport
+
+// This file contains the whole Transport to QTransport abstraction layer.
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/libp2p/go-libp2p-core/peer"
+	"github.com/libp2p/go-libp2p-core/transport"
+
+	ma "github.com/multiformats/go-multiaddr"
+	manet "github.com/multiformats/go-multiaddr-net"
+)
+
+// 2^31
+var defaultNonProxyQuality uint32 = 2147483648
+
+// 2^31+2^30
+var defaultProxyQuality uint32 = 3221225472
+
+var _ transport.QTransport = TransportUpgrader{}
+
+// Used to upgrade `transport.Transport` to `transport.QTransport`.
+// Only use it with `BaseTransport` castable to `transport.Transport`.
+type TransportUpgrader struct {
+	transport.BaseTransport
+}
+
+func (t TransportUpgrader) Dial(ctx context.Context, raddr ma.Multiaddr, p peer.ID) (transport.QCapableConn, error) {
+	conn, err := t.BaseTransport.(transport.Transport).Dial(ctx, raddr, p)
+	if err != nil {
+		return nil, err
+	}
+	return upgradedCapableConn{BaseCapableConn: conn, t: t}, nil
+}
+
+func (t TransportUpgrader) Listen(laddr ma.Multiaddr) (transport.QListener, error) {
+	l, err := t.BaseTransport.(transport.Transport).Listen(laddr)
+	if err != nil {
+		return nil, err
+	}
+	return upgradedListener{BaseListener: l, t: t}, nil
+}
+
+func (t TransportUpgrader) Score(raddr ma.Multiaddr, _ peer.ID) (transport.Score, error) {
+	if !t.CanDial(raddr) {
+		return transport.Score{}, fmt.Errorf("\"%s\" does not match %s.", raddr, t.BaseTransport)
+	}
+	if t.Proxy() {
+		if manet.IsIPLoopback(raddr) {
+			return transport.Score{
+				Quality: defaultProxyQuality >> 16,
+				Fd:      1,
+			}, nil
+		}
+		if manet.IsPrivateAddr(raddr) {
+			return transport.Score{
+				Quality: defaultProxyQuality >> 8,
+				Fd:      1,
+			}, nil
+		}
+		return transport.Score{
+			Quality: defaultProxyQuality,
+			Fd:      1,
+		}, nil
+	}
+	if manet.IsIPLoopback(raddr) {
+		return transport.Score{
+			Quality: defaultNonProxyQuality >> 16,
+			Fd:      1,
+		}, nil
+	}
+	if manet.IsPrivateAddr(raddr) {
+		return transport.Score{
+			Quality: defaultNonProxyQuality >> 8,
+			Fd:      1,
+		}, nil
+	}
+	return transport.Score{
+		Quality: defaultNonProxyQuality,
+		Fd:      1,
+	}, nil
+}
+
+// Used to upgrade `transport.CapableConn` to `transport.QCapableConn`.
+type upgradedCapableConn struct {
+	transport.BaseCapableConn
+	t transport.QTransport
+}
+
+func (c upgradedCapableConn) Quality() uint32 {
+	raddr := c.RemoteMultiaddr()
+	if c.Transport().Proxy() {
+		if manet.IsIPLoopback(raddr) {
+			return defaultProxyQuality >> 16
+		}
+		if manet.IsPrivateAddr(raddr) {
+			return defaultProxyQuality >> 8
+		}
+		return defaultProxyQuality
+	}
+	if manet.IsIPLoopback(raddr) {
+		return defaultNonProxyQuality >> 16
+	}
+	if manet.IsPrivateAddr(raddr) {
+		return defaultNonProxyQuality >> 8
+	}
+	return defaultNonProxyQuality
+}
+
+func (c upgradedCapableConn) Transport() transport.QTransport {
+	return c.t
+}
+
+type upgradedListener struct {
+	transport.BaseListener
+	t transport.QTransport
+}
+
+func (l upgradedListener) Accept() (transport.QCapableConn, error) {
+	c, err := l.BaseListener.(transport.Listener).Accept()
+	if err != nil {
+		return nil, err
+	}
+	return upgradedCapableConn{BaseCapableConn: c, t: l.t}, nil
+}