fix: xor

gold/link/crypto_test.go

@@ -3,6 +3,7 @@ package link
 import (
 	"bytes"
 	"crypto/rand"
+	"io"
 	"testing"
 )
 
@@ -10,15 +11,20 @@ func TestXOR(t *testing.T) {
 	m := Me{
 		mask: 0x12345678_90abcdef,
 	}
-	buf := make([]byte, 65535)
-	for i := 1; i < 65536; i++ {
+	buf := make([]byte, 4096)
+	buf2 := make([]byte, 4096)
+	for i := 1; i < 4096; i++ {
 		data := buf[:i]
-		_, err := rand.Read(data)
+		orgdata := buf2[:i]
+		r1 := bytes.NewBuffer(data[:0])
+		r2 := bytes.NewBuffer(orgdata[:0])
+		w := io.MultiWriter(r1, r2)
+		_, err := io.CopyN(w, rand.Reader, int64(i))
 		if err != nil {
 			t.Fatal(err)
 		}
-		if !bytes.Equal(m.xor(m.xor(data)), data) {
-			t.Fatal("unexpected xor at ", i)
+		if !bytes.Equal(m.xordec(m.xorenc(r1.Bytes())), r2.Bytes()) {
+			t.Fatal("unexpected xor at", i)
 		}
 	}
 }