Added better prediction of waku RLP key type and value

waku/handshake.go

@@ -1,8 +1,11 @@
 package waku
 
 import (
+	"bytes"
+	"encoding/binary"
 	"errors"
 	"fmt"
+	"github.com/davecgh/go-spew/spew"
 	"io"
 	"math"
 	"reflect"
@@ -202,28 +205,36 @@ loop:
 }
 
 func (o statusOptions) decodeKey(s *rlp.Stream) (statusOptionKey, statusOptionKeyType, error) {
-	var key statusOptionKey
+	// Problem: A string will be encoded to bytes, and bytes can be decoded into a uint.
+	// This means that an encoded string that is attempted to be decoded into a uint will succeed and return a valid uint.
+	// This is bad because wildly inaccurate keys can be returned. See below examples:
+	// - string("0"); encodes to byte(48); decodes to uint(48).
+	// - string("111"); encodes to []byte(131, 49, 49, 49); decode to uint(3223857).
+	// This means an expected index of 0 will be returned as 48. An expected index of 111 will be returned as 3223857
 
-	// If statusOptionKey (uint) can be decoded return it
+	// Solution: We need to first test if the RLP stream can be decoded into a string.
-	// Ignore the first error and attempt string decoding
+	// If a stream can be decoded into a string, attempt to decode the string into a uint.
-	if err := s.Decode(&key); err == nil {
+	// If decoding the string into a uint is successful return the value.
-		return key, sOKTU, nil
+	// If decoding the string failed, attempt to decode as a uint. Return the result or error from this final step.
-	}
 
-	// Attempt decoding into a string
+	// decode into bytes, detect if bytes can be parsed as a string and from a string to a uint
-	var sKey string
+	var bKey []byte
-	if err := s.Decode(&sKey); err != nil {
+	if err := s.Decode(&bKey); err != nil {
-		return key, 0, err
+		return 0, 0, err
 	}
 
 	// Parse string into uint
-	uKey, err := strconv.ParseUint(sKey, 10, 64)
+	uKey, err := strconv.ParseUint(string(bKey), 10, 64)
-	if err != nil {
+	if err == nil {
-		return key, 0, err
+		return statusOptionKey(uKey), sOKTS, err
 	}
 
-	key = statusOptionKey(uKey)
+	// If statusOptionKey (uint) can be decoded return it
-	return key, sOKTS, nil
+	buf := bytes.NewBuffer(bKey)
+	uintKey, c := binary.ReadUvarint(buf)
+	spew.Dump(uintKey, c)
+
+	return statusOptionKey(uintKey), sOKTU, nil
 }
 
 // setKeyType sets a statusOptions' keyType if it hasn't previously been set

waku/handshake_test.go

@@ -1,6 +1,8 @@
 package waku
 
 import (
+	"fmt"
+	"github.com/davecgh/go-spew/spew"
 	"math"
 	"testing"
 
@@ -36,18 +38,87 @@ func TestEncodeDecodeRLP(t *testing.T) {
 	require.EqualValues(t, opts, optsDecoded)
 }
 
-func TestBackwardCompatibility(t *testing.T) {
+// TODO remove once key type issue is resolved.
-	alist := []interface{}{
+func TestKeyTypes(t *testing.T) {
-		[]interface{}{"0", math.Float64bits(2.05)},
+	uKeys := []uint{
+		0, 1, 2, 49, 50, 256, 257, 1000, 6000,
 	}
-	data, err := rlp.EncodeToBytes(alist)
-	require.NoError(t, err)
 
-	var optsDecoded statusOptions
+	for i, uKey := range uKeys {
-	err = rlp.DecodeBytes(data, &optsDecoded)
+		fmt.Printf("test %d, for key '%d'", i+1, uKey)
-	require.NoError(t, err)
+
+		encodeable := []interface{}{
+			[]interface{}{uKey, true},
+		}
+		data, err := rlp.EncodeToBytes(encodeable)
+		spew.Dump(data, err)
+
+		var optsDecoded statusOptions
+		err = rlp.DecodeBytes(data, &optsDecoded)
+		spew.Dump(optsDecoded, err)
+
+		println("\n----------------\n")
+	}
+}
+
+func TestBackwardCompatibility(t *testing.T) {
 	pow := math.Float64bits(2.05)
-	require.EqualValues(t, statusOptions{PoWRequirement: &pow}, optsDecoded)
+	lne := true
+
+	cs := []struct {
+		Input []interface{}
+		Expected statusOptions
+	}{
+		{
+			[]interface{}{
+				[]interface{}{"0", pow},
+			},
+			statusOptions{PoWRequirement: &pow, keyType: sOKTS},
+		},
+		{
+			[]interface{}{
+				[]interface{}{"2", true},
+			},
+			statusOptions{LightNodeEnabled: &lne, keyType: sOKTS},
+		},
+		{
+			[]interface{}{
+				[]interface{}{uint(2), true},
+			},
+			statusOptions{LightNodeEnabled: &lne, keyType: sOKTU},
+		},
+		{
+			[]interface{}{
+				[]interface{}{uint(0), pow},
+			},
+			statusOptions{PoWRequirement: &pow, keyType: sOKTU},
+		},
+		{
+			[]interface{}{
+				[]interface{}{"1000", true},
+			},
+			statusOptions{keyType: sOKTS},
+		},
+		{
+			[]interface{}{
+				[]interface{}{uint(1000), true},
+			},
+			statusOptions{keyType: sOKTU},
+		},
+	}
+
+	for i, c := range cs {
+		failMsg := fmt.Sprintf("test '%d'", i+1)
+
+		data, err := rlp.EncodeToBytes(c.Input)
+		require.NoError(t, err, failMsg)
+
+		var optsDecoded statusOptions
+		err = rlp.DecodeBytes(data, &optsDecoded)
+		require.NoError(t, err, failMsg)
+
+		require.EqualValues(t, c.Expected, optsDecoded, failMsg)
+	}
 }
 
 func TestForwardCompatibility(t *testing.T) {