wallet/ledger: Fix BIP-44 path serialization

Author: matevz

wallet/ledger/common.go

@@ -47,10 +47,13 @@ func getSerializedBip44Path(path []uint32) ([]byte, error) {
 		return nil, fmt.Errorf("path should contain 5 elements")
 	}
 
-	// First three elements are hardened
-	for index, element := range path[:3] {
+	for index, element := range path {
 		pos := index * 4
-		value := element | 0x80000000 // Harden all components.
+		value := element
+		// First three elements are hardened
+		if index < 3 {
+			value |= 0x80000000
+		}
 		binary.LittleEndian.PutUint32(message[pos:], value)
 	}
 	return message, nil

wallet/ledger/common_test.go

@@ -0,0 +1,128 @@
+package ledger
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetSerializedPath(t *testing.T) {
+	paths := []struct {
+		path     []uint32
+		expected []byte
+		valid    bool
+	}{
+		{
+			path:     []uint32{44, 474, 0}, // adr8, index 0
+			expected: []byte{44, 0, 0, 128, 218, 1, 0, 128, 0, 0, 0, 128},
+			valid:    true,
+		},
+		{
+			path:     []uint32{44, 474, 1}, // adr8, index 1
+			expected: []byte{44, 0, 0, 128, 218, 1, 0, 128, 1, 0, 0, 128},
+			valid:    true,
+		},
+		{
+			path:     []uint32{44, 474, 0, 0, 0}, // legacy, index 0
+			expected: []byte{44, 0, 0, 128, 218, 1, 0, 128, 0, 0, 0, 128, 0, 0, 0, 128, 0, 0, 0, 128},
+			valid:    true,
+		},
+		{
+			path:     []uint32{44, 474, 0, 0, 1}, // legacy, index 1
+			expected: []byte{44, 0, 0, 128, 218, 1, 0, 128, 0, 0, 0, 128, 0, 0, 0, 128, 1, 0, 0, 128},
+			valid:    true,
+		},
+		{
+			path:     []uint32{}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44, 474, 0, 0}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44, 474, 0, 0, 0, 0}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+	}
+
+	for _, p := range paths {
+		result, err := getSerializedPath(p.path)
+		if p.valid {
+			require.Equal(t, p.expected, result)
+		} else {
+			require.Error(t, err)
+		}
+	}
+}
+
+func TestGetSerializedBip44Path(t *testing.T) {
+	paths := []struct {
+		path     []uint32
+		expected []byte
+		valid    bool
+	}{
+		{
+			path:     []uint32{44, 60, 0, 0, 0}, // bip44, change 0, index 0
+			expected: []byte{44, 0, 0, 128, 60, 0, 0, 128, 0, 0, 0, 128, 0, 0, 0, 0, 0, 0, 0, 0},
+			valid:    true,
+		},
+		{
+			path:     []uint32{44, 60, 0, 0, 1}, // bip44, change 0, index 1
+			expected: []byte{44, 0, 0, 128, 60, 0, 0, 128, 0, 0, 0, 128, 0, 0, 0, 0, 1, 0, 0, 0},
+			valid:    true,
+		},
+		{
+			path:     []uint32{44, 60, 0, 1, 0}, // bip44, change 1, index 0
+			expected: []byte{44, 0, 0, 128, 60, 0, 0, 128, 0, 0, 0, 128, 1, 0, 0, 0, 0, 0, 0, 0},
+			valid:    true,
+		},
+		{
+			path:     []uint32{44, 60, 0, 1, 1}, // bip44, change 1, index 1
+			expected: []byte{44, 0, 0, 128, 60, 0, 0, 128, 0, 0, 0, 128, 1, 0, 0, 0, 1, 0, 0, 0},
+			valid:    true,
+		},
+		{
+			path:     []uint32{}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44, 60, 0}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44, 60, 0, 0}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+		{
+			path:     []uint32{44, 60, 0, 0, 0, 0}, // wrong length
+			expected: []byte{},
+			valid:    false,
+		},
+	}
+
+	for _, p := range paths {
+		result, err := getSerializedBip44Path(p.path)
+		if p.valid {
+			require.Equal(t, p.expected, result)
+		} else {
+			require.Error(t, err)
+		}
+	}
+}