From b4a268f4ffb9917d7978bf2fc496cf22c8948236 Mon Sep 17 00:00:00 2001
From: Simon Massey <simon@simonmassey.org>
Date: Sat, 15 Jun 2019 07:34:36 +0100
Subject: [PATCH] Fixes #15 generator test uses random source

---
 src/test/java/com/codahale/shamir/GF256Test.java | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/test/java/com/codahale/shamir/GF256Test.java b/src/test/java/com/codahale/shamir/GF256Test.java
index 079488c..bffc34d 100644
--- a/src/test/java/com/codahale/shamir/GF256Test.java
+++ b/src/test/java/com/codahale/shamir/GF256Test.java
@@ -88,9 +88,22 @@ void eval() {
     assertThat(GF256.eval(new byte[] {1, 0, 2, 3}, (byte) 2)).isEqualTo((byte) 17);
   }
 
+  private static class ZeroLastByteFirstAttemptRandom extends SecureRandom {
+    private int counter = 2;
+
+    @Override
+    public void nextBytes(byte[] b) {
+      super.nextBytes(b);
+      if (counter > 0) {
+        b[b.length - 1] = 0;
+        counter--;
+      }
+    }
+  }
+
   @Test
   void generate() {
-    final SecureRandom random = new SecureRandom();
+    final SecureRandom random = new ZeroLastByteFirstAttemptRandom();
     final byte[] p = GF256.generate(random, 5, (byte) 20);
     assertThat(p[0]).isEqualTo((byte) 20);
     assertThat(p.length).isEqualTo(6);