#!/usr/bin/perl

# Persistent perl script to respond to pass-through smnp requests

# put the following in your snmpd.conf file to call this script:
#
# Unix systems and Cygwin:
# pass_persist .1.3.6.1.4.1.8072.2.255 /path/to/pass_persisttest
# Windows systems except Cygwin:
# pass_persist .1.3.6.1.4.1.8072.2.255 perl /path/to/pass_persisttest

# Forces a buffer flush after every print
$|=1;

# Save my PID, to help kill this instance.
$PIDFILE=$ENV{'PASS_PERSIST_PIDFILE'} || "/tmp/pass_persist.pid";
open(PIDFILE, ">$PIDFILE");
print PIDFILE "$$\n";
close(PIDFILE);

use strict;

my $counter = 0;
my $place = ".1.3.6.1.4.1.8072.2.255";

while (<>){
  if (m!^PING!){
    print "PONG\n";
    next;
  }

  my $cmd = $_;
  my $req = <>;
  my $ret;
  chomp($cmd);
  chomp($req);

  if ( $cmd eq "getnext" ) {
     if (($req eq  "$place")         ||
         ($req eq  "$place.0")       ||
         ($req =~ m/$place\.0\..*/)  ||
         ($req eq  "$place.1"))       { $ret = "$place.1.0";}       # netSnmpPassString.0
  elsif (($req =~ m/$place\.1\..*/)  ||
         ($req eq  "$place.2")       ||
         ($req eq  "$place.2.0")     ||
         ($req =~ m/$place\.2\.0\..*/)    ||
         ($req eq  "$place.2.1")          ||
         ($req eq  "$place.2.1.0")        ||
         ($req =~ m/$place\.2\.1\.0\..*/) ||
         ($req eq  "$place.2.1.1")        ||
         ($req =~ m/$place\.2\.1\.1\..*/) ||
         ($req eq  "$place.2.1.2")        ||
         ($req eq  "$place.2.1.2.0")) { $ret = "$place.2.1.2.1";}   # netSnmpPassInteger.1
  elsif (($req =~ m/$place\.2\.1\.2\..*/) ||
         ($req eq  "$place.2.1.3")   ||
         ($req eq  "$place.2.1.3.0")) { $ret = "$place.2.1.3.1";}   # netSnmpPassOID.1
  elsif (($req =~ m/$place\.2\..*/)  ||
         ($req eq  "$place.3"))       { $ret = "$place.3.0";}       # netSnmpPassTimeTicks.0
  elsif (($req =~ m/$place\.3\..*/)  ||
         ($req eq  "$place.4"))       { $ret = "$place.4.0";}       # netSnmpPassIpAddress.0
  elsif (($req =~ m/$place\.4\..*/)  ||
         ($req eq  "$place.5"))       { $ret = "$place.5.0";}       # netSnmpPassCounter.0
  elsif (($req =~ m/$place\.5\..*/)  ||
         ($req eq  "$place.6"))       { $ret = "$place.6.0";}       # netSnmpPassGauge.0
  else   {
      print "NONE\n";
      next;
    }
  } else {
    if ($req eq $place) {
      print "NONE\n";
      next;
    } else {
      $ret = $req;
    }
  }

  print "$ret\n";

  if ($ret eq "$place.1.0") {
    print "string\nLife, the Universe, and Everything\n";
  } elsif ($ret eq "$place.2.1.2.1") {
    print "integer\n42\n";
  } elsif ($ret eq "$place.2.1.3.1") {
    print "objectid\n$place.99\n";
  } elsif ($ret eq "$place.3.0") {
    print "timeticks\n363136200\n";
  } elsif ($ret eq "$place.4.0") {
    print "ipaddress\n127.0.0.1\n";
  } elsif ($ret eq "$place.5.0") {
    $counter++;
    print "counter\n$counter\n";
  } elsif ($ret eq "$place.6.0") {
    print "gauge\n42\n";
  } else {
    print  "string\nack... $ret $req\n";
  }
}