I'm using Convert::BER to write a simple SNMP Trap receiver (much like Mon::SNMP, which I can't seem to find a PPM for my ActiveState). Nonetheless, I have it working pretty good except for the varbinds.

My test is returning: Convert::BER=ARRAY(0x1a67994), as one of my variables. I assume I can iterate over this with a foreach (@{<VAR_HERE>}) loop, but I keep getting the Convert::BER=ARRAY reference. I inserted comments and a Data::Dumper line to help with my (and any kind Monk's) troubleshooting.

#!/usr/bin/perl

use strict;
use IO::Socket;
use Convert::BER;
use Convert::BER qw(/^(\$|BER_)/);

    my @traptypes = ("COLDSTART", "WARMSTART", "LINKDOWN", "LINKUP", "
+AUTHFAIL", "EGPNEIGHBORLOSS", "ENTERPRISESPECIFIC");
    my %trap;

    my $sock = IO::Socket::INET->new(LocalPort => '162',
                                         Proto => 'udp'
                                    ) || die "Cannot open port";

    my $ber = new Convert::BER;

    $ber->define(
                 [ Trap_PDU              => $SEQUENCE,      BER_CONTEX
+T | BER_CONSTRUCTOR     | 0x04 ],
                 [ IpAddress             => $STRING,        BER_APPLIC
+ATION                   | 0x00 ],
                 [ Counter               => $INTEGER,       BER_APPLIC
+ATION                   | 0x01 ],
                 [ Gauge                 => $INTEGER,       BER_APPLIC
+ATION                   | 0x02 ],
                 [ TimeTicks             => $INTEGER,       BER_APPLIC
+ATION                   | 0x03 ],
                 [ Opaque                => undef,          BER_APPLIC
+ATION                   | 0x04 ]
                );

    my $buf;
    while (1) {

        $sock->recv($buf, 1500);
        my ($port, $ipaddr) = sockaddr_in($sock->peername);

        my $host = inet_ntoa($ipaddr);

        $ber->buffer($buf);
        $ber->decode(
                     SEQUENCE => [
                                  INTEGER => \$trap{'version'},
                                   STRING => \$trap{'community'},
                                 Trap_PDU => [
                                              OBJECT_ID  => \$trap{'en
+t_OID'},
                                               IpAddress => \$trap{'ag
+entaddr'},
                                                 INTEGER => \$trap{'ge
+neric_trap'},
                                                 INTEGER => \$trap{'sp
+ecific_trap'},
                                               TimeTicks => \$trap{'ti
+meticks'},
                                                SEQUENCE => [
                                                             ANY => \$
+trap{'ber_varbindlist'}
                                                            ],
                                             ],
                                 ]
                    );

        my $p = sprintf "%s\t%i\t%i\t%s\t%s\t%s\t%s\t%s\t%s\t", $host,
+ $port, $trap{'version'}, $trap{'community'}, $trap{'ent_OID'}, inet_
+ntoa($trap{'agentaddr'}), $traptypes[$trap{'generic_trap'}], $trap{'s
+pecific_trap'}, $trap{'timeticks'};

# This is the value I need to expand
print "varbind = $trap{'ber_varbindlist'}\n";

        # This is how I'm trying to do it
        my %varbind;
        my ($oid, $val);
        foreach my $i (@{$trap{'ber_varbindlist'}}) {


            $ber->buffer($i);
            $ber->decode(
                         SEQUENCE => [
                                      OBJECT_ID => \$oid,
                                            ANY => \$val,
                                     ]
                        );
            $varbind{$oid} = $val
        }

# This is dumping what I've expanded, but it isn't correct
use Data::Dumper;
print Dumper(%varbind);

        print "$p\n"
    }

[download]

Since the above is just a server (listener), I'm using another simple script to send the trap I want to analyze. The following code does NOT need to be analyzed, I just wanted to make it easy for any Monks who wanted to help out. I'm calling the following script with EXACTLY what follows:

C:\> snmptrap.pl localhost public arg1 arg2 arg3 arg4 arg5

# snmptrap.pl
#! /usr/bin/perl 

use strict; 
use Net::SNMP qw(:ALL); 

my ($session, $error) = Net::SNMP->session( 
   -hostname  => $ARGV[0], 
   -community => $ARGV[1], 
   -port      => SNMP_TRAP_PORT,      # Need to use port 162 
); 

if (!defined($session)) { 
   printf("ERROR: %s.\n", $error); 
   exit 1; 
} 

my $srcip=$ARGV[2]; 
my $dstip=$ARGV[3]; 
my $srcport=$ARGV[4]; 
my $dstport=$ARGV[5]; 
my $personality=$ARGV[6]; 
my $result = $session->trap( 
   -enterprise   => '1.3.6.1.4.1.50000', 
   -generictrap  => 6, 
   -specifictrap => 1, 
   -varbindlist  => [ 
      '1.3.6.1.4.1.50000.1.1', OCTET_STRING, "$srcip", 
      '1.3.6.1.4.1.50000.1.2', OCTET_STRING, "$dstip", 
      '1.3.6.1.4.1.50000.1.3', OCTET_STRING, "$srcport", 
      '1.3.6.1.4.1.50000.1.4', OCTET_STRING, "$dstport", 
      '1.3.6.1.4.1.50000.1.5', OCTET_STRING, "$personality" 
   ] 
); 

$session->close(); 

exit 0;

[download]

In reply to Convert::BER printing values by VinsWorldcom

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