1 files changed, 57 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/crypto/params/DESedeParameters.java b/core/src/main/java/org/spongycastle/crypto/params/DESedeParameters.java
new file mode 100644
index 00000000..498371ad
--- /dev/null
+++ b/core/src/main/java/org/spongycastle/crypto/params/DESedeParameters.java
@@ -0,0 +1,57 @@
+package org.spongycastle.crypto.params;
+
+public class DESedeParameters
+    extends DESParameters
+{
+    /*
+     * DES-EDE Key length in bytes.
+     */
+    static public final int DES_EDE_KEY_LENGTH = 24;
+
+    public DESedeParameters(
+        byte[]  key)
+    {
+        super(key);
+
+        if (isWeakKey(key, 0, key.length))
+        {
+            throw new IllegalArgumentException("attempt to create weak DESede key");
+        }
+    }
+
+    /**
+     * return true if the passed in key is a DES-EDE weak key.
+     *
+     * @param key bytes making up the key
+     * @param offset offset into the byte array the key starts at
+     * @param length number of bytes making up the key
+     */
+    public static boolean isWeakKey(
+        byte[]  key,
+        int     offset,
+        int     length)
+    {
+        for (int i = offset; i < length; i += DES_KEY_LENGTH)
+        {
+            if (DESParameters.isWeakKey(key, i))
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * return true if the passed in key is a DES-EDE weak key.
+     *
+     * @param key bytes making up the key
+     * @param offset offset into the byte array the key starts at
+     */
+    public static boolean isWeakKey(
+        byte[]  key,
+        int     offset)
+    {
+        return isWeakKey(key, offset, key.length - offset);
+    }
+}