Merge pull request #1786 from DSheirer/1783-l3h-p2-talker-alias-part-2

#1783 L3H P25P2 Talker Alias Guard Against Negative Length Aliases

Author: DSheirer

gradle.properties

@@ -1,6 +1,6 @@
 #
 # ******************************************************************************
-# Copyright (C) 2014-2023 Dennis Sheirer
+# Copyright (C) 2014-2024 Dennis Sheirer
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -28,4 +28,4 @@
 # tag name, specifically the dashes inserted before and after the alpha/beta labels.
 # See: https://github.com/DSheirer/sdrtrunk/issues/1651
 
-projectVersion=0.6.0
+projectVersion=0.7.0-alpha-1

src/main/java/io/github/dsheirer/module/decode/p25/phase2/message/mac/structure/l3harris/L3HarrisTalkerAlias.java

@@ -78,15 +78,21 @@ public P25TalkerAliasIdentifier getAlias()
     {
         if(mAliasIdentifier == null)
         {
-            int length = getLength() * 8 + getOffset();
+            int length = getLength();
 
-            if(length > getMessage().size())
+            if(length > 0)
             {
-                length = getMessage().size();
-            }
+                length *= 8;
+                length += getOffset();
+
+                if(length > getMessage().size())
+                {
+                    length = getMessage().size();
+                }
 
-            String alias = new String(getMessage().getSubMessage(ALIAS_START + getOffset(), length).getBytes()).trim();
-            mAliasIdentifier = P25TalkerAliasIdentifier.create(alias);
+                String alias = new String(getMessage().getSubMessage(ALIAS_START + getOffset(), length).getBytes()).trim();
+                mAliasIdentifier = P25TalkerAliasIdentifier.create(alias);
+            }
         }
 
         return mAliasIdentifier;