fix: truncated dns resp (#203)

common/consts/net.go

@@ -0,0 +1,5 @@
+package consts
+
+const (
+	EthernetMtu = 1500
+)

common/netutils/dns.go

@@ -15,6 +15,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/daeuniverse/dae/common/consts"
 	dnsmessage "github.com/miekg/dns"
 	"github.com/mzz2017/softwind/netproxy"
 	"github.com/mzz2017/softwind/pkg/fastrand"
@@ -240,8 +241,8 @@ func resolve(ctx context.Context, d netproxy.Dialer, dns netip.AddrPort, host st
 		}()
 	}
 	go func() {
-		buf := pool.Get(512)
+		buf := pool.GetFullCap(consts.EthernetMtu)
-		defer pool.Put(buf)
+		defer buf.Put()
 		if magicNetwork.Network == "tcp" {
 			// Read DNS response length
 			_, err := io.ReadFull(c, buf[:2])
@@ -250,7 +251,7 @@ func resolve(ctx context.Context, d netproxy.Dialer, dns netip.AddrPort, host st
 				return
 			}
 			n := binary.BigEndian.Uint16(buf)
-			if n > 512 {
+			if int(n) > cap(buf) {
 				ch <- fmt.Errorf("too big dns resp")
 				return
 			}

control/control_plane.go

@@ -705,15 +705,16 @@ func (c *ControlPlane) Serve(readyChan chan<- bool, listener *Listener) (err err
 		}
 	}()
 	go func() {
+		buf := pool.GetFullCap(consts.EthernetMtu)
+		var oob [120]byte // Size for original dest
+		defer buf.Put()
 		for {
 			select {
 			case <-c.ctx.Done():
 				return
 			default:
 			}
-			var buf [EthernetMtu]byte
+			n, oobn, _, src, err := udpConn.ReadMsgUDPAddrPort(buf, oob[:])
-			var oob [120]byte // Size for original dest
-			n, oobn, _, src, err := udpConn.ReadMsgUDPAddrPort(buf[:], oob[:])
 			if err != nil {
 				if !strings.Contains(err.Error(), "use of closed network connection") {
 					c.log.Errorf("ReadFromUDPAddrPort: %v, %v", src.String(), err)
@@ -722,8 +723,8 @@ func (c *ControlPlane) Serve(readyChan chan<- bool, listener *Listener) (err err
 			}
 			newBuf := pool.Get(n)
 			copy(newBuf, buf[:n])
-			go func(data []byte, src netip.AddrPort) {
+			go func(data pool.PB, src netip.AddrPort) {
-				defer pool.Put(data)
+				defer data.Put()
 				var realDst netip.AddrPort
 				var routingResult *bpfRoutingResult
 				pktDst := RetrieveOriginalDest(oob[:oobn])

control/dns_control.go

@@ -639,7 +639,7 @@ func (c *DnsController) dialSend(invokingDepth int, req *udpRequest, data []byte
 		}()
 
 		// We can block here because we are in a coroutine.
-		respBuf := pool.Get(512)
+		respBuf := pool.GetFullCap(consts.EthernetMtu)
 		defer pool.Put(respBuf)
 		for {
 			// Wait for response.

control/udp_endpoint.go

@@ -11,15 +11,12 @@ import (
 	"sync"
 	"time"
 
+	"github.com/daeuniverse/dae/common/consts"
 	"github.com/daeuniverse/dae/component/outbound/dialer"
 	"github.com/mzz2017/softwind/netproxy"
 	"github.com/mzz2017/softwind/pool"
 )
 
-const (
-	EthernetMtu = 1500
-)
-
 type UdpHandler func(data []byte, from netip.AddrPort) error
 
 type UdpEndpoint struct {
@@ -34,8 +31,7 @@ type UdpEndpoint struct {
 }
 
 func (ue *UdpEndpoint) start() {
-	buf := pool.Get(EthernetMtu)
+	buf := pool.GetFullCap(consts.EthernetMtu)
-	buf = buf[:cap(buf)]
 	defer pool.Put(buf)
 	for {
 		n, from, err := ue.conn.ReadFrom(buf[:])

go.mod

@@ -12,7 +12,7 @@ require (
 	github.com/json-iterator/go v1.1.12
 	github.com/miekg/dns v1.1.55
 	github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826
-	github.com/mzz2017/softwind v0.0.0-20230708102709-26ff44839573
+	github.com/mzz2017/softwind v0.0.0-20230710142544-73a557cea4a4
 	github.com/okzk/sdnotify v0.0.0-20180710141335-d9becc38acbd
 	github.com/safchain/ethtool v0.3.0
 	github.com/sirupsen/logrus v1.9.3

go.sum

@@ -91,8 +91,8 @@ github.com/mzz2017/disk-bloom v1.0.1 h1:rEF9MiXd9qMW3ibRpqcerLXULoTgRlM21yqqJl1B
 github.com/mzz2017/disk-bloom v1.0.1/go.mod h1:JLHETtUu44Z6iBmsqzkOtFlRvXSlKnxjwiBRDapizDI=
 github.com/mzz2017/quic-go v0.0.0-20230706143320-cc858d4932b7 h1:9zmZilN02x3byMB2X3x+B4iyKHkucv70WA4hsyZkjo8=
 github.com/mzz2017/quic-go v0.0.0-20230706143320-cc858d4932b7/go.mod h1:3H6d55CEofIWWr3gQThiB27+hA3WG5tATtPovzEYPAA=
-github.com/mzz2017/softwind v0.0.0-20230708102709-26ff44839573 h1:fDndoUP5FyJKZM0LJ9nqZJhZF9eLhgfG46xwxO4UHww=
+github.com/mzz2017/softwind v0.0.0-20230710142544-73a557cea4a4 h1:U6oSJf+dwVXpBZGi73l77igid+sOy4jgJucjSrfowFU=
-github.com/mzz2017/softwind v0.0.0-20230708102709-26ff44839573/go.mod h1:Fz8fgR7/dbnfR6RLpeOMkUDyebq4xShdmjj+cE5jnJ4=
+github.com/mzz2017/softwind v0.0.0-20230710142544-73a557cea4a4/go.mod h1:Fz8fgR7/dbnfR6RLpeOMkUDyebq4xShdmjj+cE5jnJ4=
 github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
 github.com/nxadm/tail v1.4.8 h1:nPr65rt6Y5JFSKQO7qToXr7pePgD6Gwiw05lkbyAQTE=
 github.com/nxadm/tail v1.4.8/go.mod h1:+ncqLTQzXmGhMZNUePPaPqPvBxHAIsmXswZKocGu+AU=