android: Fix version string on older Android releases

SECURITY_PATCH is apparently only available since Android 6.

diff --git a/src/frontends/android/app/src/main/java/org/strongswan/android/logic/CharonVpnService.java b/src/frontends/android/app/src/main/java/org/strongswan/android/logic/CharonVpnService.java
index 5ef5e8731715b560bd9010106eee0ad00886119e..d8e07a87395263e59288d0b88c5a61cb364a9448 100644 (file)
--- a/src/frontends/android/app/src/main/java/org/strongswan/android/logic/CharonVpnService.java
+++ b/src/frontends/android/app/src/main/java/org/strongswan/android/logic/CharonVpnService.java
@@ -1031,8 +1031,12 @@ public class CharonVpnService extends VpnService implements Runnable, VpnStateSe
         */
        private static String getAndroidVersion()
        {
-               return "Android " + Build.VERSION.RELEASE + " - " + Build.DISPLAY +
-                          "/" + Build.VERSION.SECURITY_PATCH;
+               String version = "Android " + Build.VERSION.RELEASE + " - " + Build.DISPLAY;
+               if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
+               {
+                       version += "/" + Build.VERSION.SECURITY_PATCH;
+               }
+               return version;
        }
 
        /**