[Fuzzing] fuzzing support for oss-fuzz

Signed-off-by: Arjun Singh <ajsinghyadav00@gmail.com>

BUILD.md

@@ -69,3 +69,18 @@ This will produce a version number of
 ## Layout
 
 The GoBGP project adopts [Standard Go Project Layout](https://github.com/golang-standards/project-layout).
+
+
+## Fuzzing
+
+Run [Go Fuzzing](https://go.dev/security/fuzz)
+
+```bash
+go test -fuzz=FuzzParseRTR                      $PWD/pkg/packet/rtr
+go test -fuzz=FuzzParseBMPMessage               $PWD/pkg/packet/bmp
+go test -fuzz=FuzzParseBGPMessage               $PWD/pkg/packet/bgp
+go test -fuzz=FuzzParseLargeCommunity           $PWD/pkg/packet/bgp
+go test -fuzz=FuzzParseFlowSpecComponents       $PWD/pkg/packet/bgp
+go test -fuzz=FuzzMRT                           $PWD/pkg/packet/mrt
+go test -fuzz=FuzzZapi                          $PWD/internal/pkg/zebra
+```

internal/pkg/zebra/zapi_test.go

@@ -1120,3 +1120,28 @@ func Test_vrfLabelBody(t *testing.T) {
 		assert.Equal(bufIn, bufOut)
 	}
 }
+
+func FuzzZapi(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data []byte) {
+
+		if len(data) < 16 {
+			return
+		}
+
+		for v := MinZapiVer; v <= MaxZapiVer; v++ {
+
+			ZAPIHeaderSize := int(HeaderSize(v))
+
+			hd := &Header{}
+			err := hd.decodeFromBytes(data[:ZAPIHeaderSize])
+
+			if err != nil {
+				return
+			}
+
+			software := NewSoftware(v, "")
+			parseMessage(hd, data[:ZAPIHeaderSize], software)
+		}
+	})
+}

pkg/packet/bgp/bgp_test.go

@@ -3715,3 +3715,17 @@ func Test_BGPOpenDecodeCapabilities(t *testing.T) {
 	assert.Equal(t, tuples[0].RouteFamily, RF_IPv4_UC)
 	assert.Equal(t, tuples[0].Mode, BGP_ADD_PATH_SEND)
 }
+
+func FuzzParseBGPMessage(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data []byte) {
+		ParseBGPMessage(data)
+	})
+}
+
+func FuzzParseFlowSpecComponents(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data string) {
+		ParseFlowSpecComponents(RF_FS_IPv4_UC, data)
+	})
+}

pkg/packet/bgp/validate_test.go

@@ -421,3 +421,10 @@ func TestValidateLargeCommunities(t *testing.T) {
 	assert.Nil(err)
 	assert.True(len(a.Values) == 2)
 }
+
+func FuzzParseLargeCommunity(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data string) {
+		ParseLargeCommunity(data)
+	})
+}

pkg/packet/bmp/bmp_test.go

@@ -158,3 +158,10 @@ func Test_RouteMonitoringUnknownType(t *testing.T) {
 	_, err := ParseBMPMessage(data)
 	require.NoError(t, err)
 }
+
+func FuzzParseBMPMessage(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data []byte) {
+		ParseBMPMessage(data)
+	})
+}

pkg/packet/mrt/mrt_test.go

@@ -300,3 +300,21 @@ func TestMrtSplit(t *testing.T) {
 	t.Logf("scanner scanned %d serialized keepalives from the buffer", numread)
 	assert.Equal(t, numwrite, numread)
 }
+
+func FuzzMRT(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data []byte) {
+		if len(data) < 16 {
+			return
+		}
+
+		hdr := &MRTHeader{}
+		err := hdr.DecodeFromBytes(data[:MRT_COMMON_HEADER_LEN])
+
+		if err != nil {
+			return
+		}
+
+		ParseMRTBody(hdr, data[MRT_COMMON_HEADER_LEN:])
+	})
+}

pkg/packet/rtr/rtr_test.go

@@ -115,3 +115,10 @@ func Test_RTRErrorReport(t *testing.T) {
 	// when it has both "erroneous PDU" and "Arbitrary Text"
 	verifyRTRMessage(t, NewRTRErrorReport(CORRUPT_DATA, errPDU, errText2))
 }
+
+func FuzzParseRTR(f *testing.F) {
+
+	f.Fuzz(func(t *testing.T, data []byte) {
+		ParseRTR(data)
+	})
+}