1 files changed, 24 insertions, 0 deletions
diff --git a/ethutil/rand.go b/ethutil/rand.go
new file mode 100644
index 000000000..91dafec7e
--- /dev/null
+++ b/ethutil/rand.go
@@ -0,0 +1,24 @@
+package ethutil
+
+import (
+	"crypto/rand"
+	"encoding/binary"
+	"io"
+)
+
+func randomUint64(r io.Reader) (uint64, error) {
+	b := make([]byte, 8)
+	n, err := r.Read(b)
+	if n != len(b) {
+		return 0, io.ErrShortBuffer
+	}
+	if err != nil {
+		return 0, err
+	}
+	return binary.BigEndian.Uint64(b), nil
+}
+
+// RandomUint64 returns a cryptographically random uint64 value.
+func RandomUint64() (uint64, error) {
+	return randomUint64(rand.Reader)
+}