From 98c12387a603b7f763bc225442cd67fb66a430a6 Mon Sep 17 00:00:00 2001
From: Rajasekaran Nagarajan <rnagarajan@novell.com>
Date: Tue, 19 Dec 2006 23:21:24 +0000
Subject: [PATCH] Changes to make ProtectedData.Protect() and
 ProtectedData.Unprotect() use entropy.

---
 CASA/micasad/lss/CASACrypto.cs | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/CASA/micasad/lss/CASACrypto.cs b/CASA/micasad/lss/CASACrypto.cs
index 10453b63..6130fc45 100644
--- a/CASA/micasad/lss/CASACrypto.cs
+++ b/CASA/micasad/lss/CASACrypto.cs
@@ -678,7 +678,7 @@ namespace sscs.crypto
                 fs.Close();
 
                 baSavedMasterPasscode = new byte[16];
-                baSavedMasterPasscode = ProtectedData.Unprotect( encryptedMasterPasscode, null, DataProtectionScope.CurrentUser );
+                baSavedMasterPasscode = ProtectedData.Unprotect( encryptedMasterPasscode, RetrieveIV(fileName, new byte[16]), DataProtectionScope.CurrentUser );
             }
             catch (CryptographicException e)
             {
@@ -740,7 +740,7 @@ namespace sscs.crypto
                 myRijndael.GenerateKey();
                 baPasscode = myRijndael.Key;
 
-                byte [] encryptedMasterPasscode = ProtectedData.Protect( baPasscode, null, DataProtectionScope.CurrentUser );
+                byte [] encryptedMasterPasscode = ProtectedData.Protect( baPasscode, GenerateAndSaveIV(fileName, null), DataProtectionScope.CurrentUser );
                 FileStream fs = new FileStream(fileName, FileMode.Create);
                 File.SetAttributes(fileName, FileAttributes.Hidden);
                 fs.Write(encryptedMasterPasscode, 0, encryptedMasterPasscode.Length);
@@ -801,8 +801,18 @@ namespace sscs.crypto
 
         private static byte[] GenerateAndSaveIV(string sFileName, RijndaelManaged theRiManaged)
         {
-            theRiManaged.GenerateIV();
-            byte[] baIV = theRiManaged.IV;
+            byte[] baIV = null;
+	    if ( theRiManaged != null )
+	    {
+		theRiManaged.GenerateIV();
+		baIV = theRiManaged.IV;
+	    }
+	    else
+	    {
+		RandomNumberGenerator rng = RandomNumberGenerator.Create ();
+		baIV = new byte [16];
+		rng.GetBytes (baIV);
+	    }
 
             try
             {