Create a Curve25519 asymmetric master secret for users without.

Fixes #1701

src/org/thoughtcrime/securesms/DatabaseUpgradeActivity.java

@@ -43,11 +43,13 @@ public class DatabaseUpgradeActivity extends Activity {
   public static final int MMS_BODY_VERSION                     = 46;
   public static final int TOFU_IDENTITIES_VERSION              = 50;
   public static final int CURVE25519_VERSION                   = 63;
+  public static final int ASYMMETRIC_MASTER_SECRET_FIX_VERSION = 73;
 
   private static final SortedSet<Integer> UPGRADE_VERSIONS = new TreeSet<Integer>() {{
     add(NO_MORE_KEY_EXCHANGE_PREFIX_VERSION);
     add(TOFU_IDENTITIES_VERSION);
     add(CURVE25519_VERSION);
+    add(ASYMMETRIC_MASTER_SECRET_FIX_VERSION);
   }};
 
   private MasterSecret masterSecret;

src/org/thoughtcrime/securesms/database/DatabaseFactory.java

@@ -16,6 +16,7 @@
  */
 package org.thoughtcrime.securesms.database;
 
+import android.content.ContentValues;
 import android.content.Context;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
@@ -26,6 +27,7 @@ import android.util.Log;
 import org.thoughtcrime.securesms.DatabaseUpgradeActivity;
 import org.thoughtcrime.securesms.crypto.DecryptingPartInputStream;
 import org.thoughtcrime.securesms.crypto.DecryptingQueue;
+import org.thoughtcrime.securesms.crypto.MasterSecretUtil;
 import org.whispersystems.textsecure.crypto.IdentityKey;
 import org.whispersystems.textsecure.crypto.InvalidMessageException;
 import org.whispersystems.textsecure.crypto.MasterCipher;
@@ -419,6 +421,41 @@ public class DatabaseFactory {
       }
     }
 
+    if (fromVersion < DatabaseUpgradeActivity.ASYMMETRIC_MASTER_SECRET_FIX_VERSION) {
+      if (!MasterSecretUtil.hasAsymmericMasterSecret(context)) {
+        MasterSecretUtil.generateAsymmetricMasterSecret(context, masterSecret);
+
+        MasterCipher masterCipher = new MasterCipher(masterSecret);
+        Cursor       cursor       = null;
+
+        try {
+          cursor = db.query(SmsDatabase.TABLE_NAME,
+                            new String[] {SmsDatabase.ID, SmsDatabase.BODY, SmsDatabase.TYPE},
+                            SmsDatabase.TYPE + " & ? == 0",
+                            new String[] {String.valueOf(SmsDatabase.Types.ENCRYPTION_MASK)},
+                            null, null, null);
+
+          while (cursor.moveToNext()) {
+            long   id   = cursor.getLong(0);
+            String body = cursor.getString(1);
+            long   type = cursor.getLong(2);
+
+            String encryptedBody = masterCipher.encryptBody(body);
+
+            ContentValues update = new ContentValues();
+            update.put(SmsDatabase.BODY, encryptedBody);
+            update.put(SmsDatabase.TYPE, type | SmsDatabase.Types.ENCRYPTION_SYMMETRIC_BIT);
+
+            db.update(SmsDatabase.TABLE_NAME, update, SmsDatabase.ID  + " = ?",
+                      new String[] {String.valueOf(id)});
+          }
+        } finally {
+          if (cursor != null)
+            cursor.close();
+        }
+      }
+    }
+
     db.setTransactionSuccessful();
     db.endTransaction();