Merge dae73eaa9c into 8a8ad2be81

Before this commit: the printing of a rule results in
a pointer address.

After this commit: the printing of a rules results in
a human-readable text.

Resolves: #104

Signed-off-by: Paul Greenberg <greenpau@outlook.com>

.gitignore

@@ -0,0 +1 @@
+nftables.test

README.md

@@ -21,4 +21,12 @@ the data types/API will be identified as more functionality is added.
 
 Contributions are very welcome!
 
+### Testing Changes
 
+Run the following commands to test your changes:
+
+```bash
+go test ./...
+go test -c github.com/google/nftables
+sudo ./nftables.test -test.v -run_system_tests
+```

expr/ct.go

@@ -110,6 +110,12 @@ const (
 	CtStateUDPREPLIED
 )
 
+const (
+	// https://git.netfilter.org/libnftnl/tree/src/expr/ct.c?id=116e95aa7b6358c917de8c69f6f173874030b46b#n31
+	CtDirOriginal = iota
+	CtDirReply
+)
+
 // https://git.netfilter.org/libnftnl/tree/src/obj/ct_timeout.c?id=116e95aa7b6358c917de8c69f6f173874030b46b#n57
 var CtStateUDPTimeoutDefaults CtStatePolicyTimeout = map[uint16]uint32{
 	CtStateUDPUNREPLIED: 30,
@@ -122,6 +128,7 @@ type Ct struct {
 	SourceRegister bool
 	Key            CtKey
 	Direction      uint32
+	OptDirection   bool
 }
 
 func (e *Ct) marshal(fam byte) ([]byte, error) {
@@ -165,10 +172,16 @@ func (e *Ct) marshalData(fam byte) ([]byte, error) {
 	exprData = append(exprData, regData...)
 
 	switch e.Key {
+	case CtKeyPKTS, CtKeyBYTES, CtKeyAVGPKT, CtKeyL3PROTOCOL, CtKeyPROTOCOL:
+		if !e.OptDirection {
+			break
+		}
+
+		fallthrough
 	case CtKeySRC, CtKeyDST, CtKeyPROTOSRC, CtKeyPROTODST, CtKeySRCIP, CtKeyDSTIP, CtKeySRCIP6, CtKeyDSTIP6:
 		regData, err = netlink.MarshalAttributes(
 			[]netlink.Attribute{
-				{Type: unix.NFTA_CT_DIRECTION, Data: binaryutil.BigEndian.PutUint32(e.Direction)},
+				{Type: unix.NFTA_CT_DIRECTION, Data: []byte{uint8(e.Direction)}},
 			},
 		)
 		if err != nil {
@@ -186,6 +199,8 @@ func (e *Ct) unmarshal(fam byte, data []byte) error {
 		return err
 	}
 	ad.ByteOrder = binary.BigEndian
+
+	var hasDirection bool
 	for ad.Next() {
 		switch ad.Type() {
 		case unix.NFTA_CT_KEY:
@@ -193,12 +208,19 @@ func (e *Ct) unmarshal(fam byte, data []byte) error {
 		case unix.NFTA_CT_DREG:
 			e.Register = ad.Uint32()
 		case unix.NFTA_CT_DIRECTION:
-			e.Direction = ad.Uint32()
+			e.Direction = uint32(ad.Uint8())
+			hasDirection = true
 		case unix.NFTA_CT_SREG:
 			e.SourceRegister = true
 			e.Register = ad.Uint32()
 		}
 	}
+
+	switch e.Key {
+	case CtKeyPKTS, CtKeyBYTES, CtKeyAVGPKT, CtKeyL3PROTOCOL, CtKeyPROTOCOL:
+		e.OptDirection = hasDirection
+	}
+
 	return ad.Err()
 }
 

expr/ct_test.go

@@ -78,6 +78,22 @@ func TestCt(t *testing.T) {
 				Direction: 1,
 			},
 		},
+		{
+			name: "Unmarshal Ct packets direction original case",
+			ct: Ct{
+				Register:     1,
+				Key:          CtKeyPKTS,
+				Direction:    CtDirOriginal,
+				OptDirection: true,
+			},
+		},
+		{
+			name: "Unmarshal Ct bytes without direction case",
+			ct: Ct{
+				Register: 1,
+				Key:      CtKeyBYTES,
+			},
+		},
 	}
 
 	for _, tt := range tests {

expr/verdict.go

@@ -24,6 +24,15 @@ import (
 	"golang.org/x/sys/unix"
 )
 
+const (
+	NFT_DROP   = 0
+	NFT_ACCEPT = 1
+	NFT_STOLEN = 2
+	NFT_QUEUE  = 3
+	NFT_REPEAT = 4
+	NFT_STOP   = 5
+)
+
 // This code assembles the verdict structure, as expected by the
 // nftables netlink API.
 // For further information, consult:
@@ -129,3 +138,37 @@ func (e *Verdict) unmarshal(fam byte, data []byte) error {
 	}
 	return ad.Err()
 }
+
+func (e *Verdict) String() string {
+	var v string
+	switch e.Kind {
+	case unix.NFT_RETURN:
+		v = "return" // -0x5
+	case unix.NFT_GOTO:
+		v = "goto" // -0x4
+	case unix.NFT_JUMP:
+		v = "jump" // NFT_JUMP = -0x3
+	case unix.NFT_BREAK:
+		v = "break" // NFT_BREAK = -0x2
+	case unix.NFT_CONTINUE:
+		v = "continue" // NFT_CONTINUE = -0x1
+	case NFT_DROP:
+		v = "drop"
+	case NFT_ACCEPT:
+		v = "accept"
+	case NFT_STOLEN:
+		v = "stolen"
+	case NFT_QUEUE:
+		v = "queue"
+	case NFT_REPEAT:
+		v = "repeat"
+	case NFT_STOP:
+		v = "stop"
+	default:
+		v = fmt.Sprintf("verdict %v", e.Kind)
+	}
+	if e.Chain != "" {
+		return v + " " + e.Chain
+	}
+	return v
+}

nftables_test.go

@@ -266,12 +266,27 @@ func TestRuleOperations(t *testing.T) {
 		expr.VerdictDrop,
 	}
 
+	wantStrings := []string{
+		"queue",
+		"accept",
+		"queue",
+		"accept",
+		"drop",
+		"drop",
+	}
+
 	for i, r := range rules {
 		rr, _ := r.Exprs[0].(*expr.Verdict)
 
 		if rr.Kind != want[i] {
 			t.Fatalf("bad verdict kind at %d", i)
 		}
+
+		if rr.String() != wantStrings[i] {
+			t.Fatalf("bad verdict string at %d: %s (received) vs. %s (expected)", i, rr.String(), wantStrings[i])
+		}
+
+		t.Logf("%s", rr)
 	}
 }
 

nftables_test.sh

@@ -0,0 +1,3 @@
+go test ./...
+go test -c github.com/google/nftables
+sudo ./nftables.test -test.v -run_system_tests