1 files changed, 43 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/crypto/signers/RandomDSAKCalculator.java b/core/src/main/java/org/spongycastle/crypto/signers/RandomDSAKCalculator.java
new file mode 100644
index 00000000..fb8e3ae7
--- /dev/null
+++ b/core/src/main/java/org/spongycastle/crypto/signers/RandomDSAKCalculator.java
@@ -0,0 +1,43 @@
+package org.spongycastle.crypto.signers;
+
+import java.math.BigInteger;
+import java.security.SecureRandom;
+
+class RandomDSAKCalculator
+    implements DSAKCalculator
+{
+    private static final BigInteger ZERO = BigInteger.valueOf(0);
+
+    private BigInteger q;
+    private SecureRandom random;
+
+    public boolean isDeterministic()
+    {
+        return false;
+    }
+
+    public void init(BigInteger n, SecureRandom random)
+    {
+        this.q = n;
+        this.random = random;
+    }
+
+    public void init(BigInteger n, BigInteger d, byte[] message)
+    {
+        throw new IllegalStateException("Operation not supported");
+    }
+
+    public BigInteger nextK()
+    {
+        int qBitLength = q.bitLength();
+
+        BigInteger k;
+        do
+        {
+            k = new BigInteger(qBitLength, random);
+        }
+        while (k.equals(ZERO) || k.compareTo(q) >= 0);
+
+        return k;
+    }
+}