Suggestions:
   You are able to view the data in some way shape or form, so I would either 
      A) figure out how to get that data out in a stream (I.e calling an executable to provide that data on the fly for your parser) or 
      B) instead of pulling the binary data, convert it to text, compress that and munge the compressed text

   Determine what types of entries are in the file.
   Just looking at the data at hand I see at least 2 unique type of entries and a whole slew of other things to help with a parser. 
      One msg from the kernel, and one msg from firewalld.
      Next we notice that the kernel is "Temporarily" blocking 
         does it also log permanent blocks? 
         does this line correlate to an earier firewalld line?

      The firewalld process is stating it denied a packet..
      There is all sorts of juicy bits in there..

      First off, the deny. 
         What other actions can it take?
      Then the interface.. 
         what other interfaces are there?
      The next number is interesting as I have no idea what its correlated to 
         do all denies get stamped with 48? 
         or packets on eth0, 
         or tcp packets, 
         or tcp packets destined for X port?
      Next the type 
         what other types are coming through?..