initial reshuffle

1 files changed, 25 insertions, 0 deletions

diff --git a/core/src/main/java/org/bouncycastle/pqc/math/linearalgebra/RandUtils.java b/core/src/main/java/org/bouncycastle/pqc/math/linearalgebra/RandUtils.java
new file mode 100644
index 00000000..dbb1d4a8
--- /dev/null
+++ b/core/src/main/java/org/bouncycastle/pqc/math/linearalgebra/RandUtils.java
@@ -0,0 +1,25 @@
+package org.bouncycastle.pqc.math.linearalgebra;
+
+import java.security.SecureRandom;
+
+public class RandUtils
+{
+    static int nextInt(SecureRandom rand, int n)
+    {
+
+        if ((n & -n) == n)  // i.e., n is a power of 2
+        {
+            return (int)((n * (long)(rand.nextInt() >>> 1)) >> 31);
+        }
+
+        int bits, value;
+        do
+        {
+            bits = rand.nextInt() >>> 1;
+            value = bits % n;
+        }
+        while (bits - value + (n - 1) < 0);
+
+        return value;
+    }
+}