# SNMP::Info::CDP # Max Baker # # Changes since Version 0.7 Copyright (c) 2004 Max Baker # All rights reserved. # # Copyright (c) 2002,2003 Regents of the University of California # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, # this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # * Neither the name of the University of California, Santa Cruz nor the # names of its contributors may be used to endorse or promote products # derived from this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES # (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; # LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON # ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. package SNMP::Info::CDP; $VERSION = 0.8; # $Id$ use strict; use Exporter; use SNMP::Info; use Carp; @SNMP::Info::CDP::ISA = qw/SNMP::Info Exporter/; @SNMP::Info::CDP::EXPORT_OK = qw//; use vars qw/$VERSION $DEBUG %FUNCS %GLOBALS %MIBS %MIBS_V1 %MUNGE $INIT/; # Debug $DEBUG=0; $SNMP::debugging=$DEBUG; # Five data structures required by SNMP::Info $INIT = 0; %MIBS = ( 'CISCO-CDP-MIB' => 'cdpGlobalRun' ); %MIBS_V1 = ( 'CISCO-CDP-MIB-V1SMI' => 'cdpGlobalRun' ); # Notice we dont inherit the default GLOBALS and FUNCS # only the default MUNGE. %GLOBALS = ( 'cdp_run' => 'cdpGlobalRun', 'cdp_interval' => 'cdpGlobalMessageInterval', 'cdp_holdtime' => 'cdpGlobalHoldTime', 'cdp_id' => 'cdpGlobalDeviceId', ); %FUNCS = ( 'c_index' => 'cdpCacheIfIndex', 'c_proto' => 'cdpCacheAddressType', 'c_ip' => 'cdpCacheAddress', 'c_ver' => 'cdpCacheVersion', 'c_id' => 'cdpCacheDeviceId', 'c_port' => 'cdpCacheDevicePort', 'c_platform' => 'cdpCachePlatform', 'c_capabilities' => 'cdpCacheCapabilities', 'c_domain' => 'cdpCacheVTPMgmtDomain', 'c_vlan' => 'cdpCacheNativeVLAN', 'c_duplex' => 'cdpCacheDuplex' ); %MUNGE = ( 'c_capabilities' => \&munge_caps, 'c_platform' => \&munge_null, 'c_domain' => \&munge_null, 'c_port' => \&munge_null, 'c_id' => \&munge_null, 'c_ver' => \&munge_null, 'c_ip' => \&SNMP::Info::munge_ip ); # munge_null() - removes nulls (\0) sub munge_null { my $text = shift || return; $text =~ s/\0//g; return $text; } sub munge_caps { my $caps = shift; return undef unless defined $caps; my $bits = substr(unpack("B*",$caps),-7); return $bits; } sub hasCDP { my $cdp = shift; my $ver = $cdp->{_version}; # SNMP v1 clients dont have the globals if (defined $ver and $ver == 1){ my $c_ip = $cdp->c_ip(); # See if anything in cdp cache, if so we have cdp return 1 if (defined $c_ip and scalar(keys %$c_ip)) ; return undef; } return $cdp->cdp_run(); } sub c_if { my $cdp = shift; # See if by some miracle Cisco implemented the cdpCacheIfIndex entry my $c_index = $cdp->c_index(); return $c_index if defined $c_index; # Nope, didn't think so. Now we fake it. my $c_ip = $cdp->c_ip(); unless (defined $c_ip){ $cdp->{error} = "SNMP::Info::CDP::c_if() - Device doesn't have c_ip() data. Can't fake c_index()"; $DEBUG and carp($cdp->error(1)); return undef; } my %c_if; foreach my $key (keys %$c_ip){ next unless defined $key; my $iid = $key; # Truncate .1 from cdp cache entry $iid =~ s/\.\d+$//; $c_if{$key} = $iid; } return \%c_if; } 1; __END__ =head1 NAME SNMP::Info::CDP - Perl5 Interface to Cisco Discovery Protocol (CDP) using SNMP =head1 AUTHOR Max Baker (C) =head1 SYNOPSIS my $cdp = new SNMP::Info ( AutoSpecify => 1, Debug => 1, DestHost => 'router', Community => 'public', Version => 2 ); my $class = $cdp->class(); print " Using device sub class : $class\n"; $hascdp = $cdp->hasCDP() ? 'yes' : 'no'; # Print out a map of device ports with CDP neighbors: my $interfaces = $cdp->interfaces(); my $c_if = $cdp->c_if(); my $c_ip = $cdp->c_ip(); my $c_port = $cdp->c_port(); foreach my $cdp_key (keys %$c_ip){ my $iid = $c_if->{$cdp_key}; my $port = $interfaces->{$iid}; my $neighbor = $c_ip->{$cdp_key}; my $neighbor_port = $c_port->{$cdp_key}; print "Port : $port connected to $neighbor / $neighbor_port\n"; } =head1 DESCRIPTION SNMP::Info::CDP is a subclass of SNMP::Info that provides an object oriented interface to CDP information through SNMP. CDP is a Layer 2 protocol that supplies topology information of devices that also speak CDP, mostly switches and routers. CDP is implemented in Cisco and some HP devices. Create or use a device subclass that inherits this class. Do not use directly. Each device implements a subset of the global and cache entries. Check the return value to see if that data is held by the device. =head2 Inherited Classes None. =head2 Required MIBs =over =item CISCO-CDP-MIB =back MIBs can be found at ftp://ftp.cisco.com/pub/mibs/v2/v2.tar.gz =head1 GLOBAL METHODS These are methods that return scalar values from SNMP =over =item $cdp->hasCDP() Is CDP is active in this device? Accounts for SNMP version 1 devices which may have CDP but not cdp_run() =item $cdp->cdp_run() Is CDP enabled on this device? Note that a lot of Cisco devices that implement CDP don't implement this value. @#%$! (B) =item $cdp->cdp_interval() Interval in seconds at which CDP messages are generated. (B) =item $cdp->cdp_holdtime() Time in seconds that CDP messages are kept. (B) =item $cdp->cdp_id() Returns CDP device ID. This is the device id broadcast via CDP to other devices, and is what is retrieved from remote devices with $cdp->id(). (B) =back =head1 TABLE METHODS These are methods that return tables of information in the form of a reference to a hash. =head2 CDP CACHE ENTRIES =over =item $cdp->c_capabilities() Returns Device Functional Capabilities. Results are munged into an ascii binary string, 7 digits long, MSB. Each digit represents a bit from the table below. From L: (Bit) - Description =over =item (0x40) - Provides level 1 functionality. =item (0x20) - The bridge or switch does not forward IGMP Report packets on nonrouter ports. =item (0x10) - Sends and receives packets for at least one network layer protocol. If the device is routing the protocol, this bit should not be set. =item (0x08) - Performs level 2 switching. The difference between this bit and bit 0x02 is that a switch does not run the Spanning-Tree Protocol. This device is assumed to be deployed in a physical loop-free topology. =item (0x04) - Performs level 2 source-route bridging. A source-route bridge would set both this bit and bit 0x02. =item (0x02) - Performs level 2 transparent bridging. =item (0x01) - Performs level 3 routing for at least one network layer protocol. =back Thanks to Martin Lorensen C for a pointer to this information. (B) =item $cdp->c_domain() Returns remote VTP Management Domain as defined in CISCO-VTP-MIB::managementDomainName (B) =item $cdp->c_duplex() Returns the port duplex status from remote devices. (B) =item $cdp->c_id() Returns remote device id string (B) =item $cdp->c_if() Returns the mapping to the SNMP Interface Table. Note that a lot devices don't implement $cdp->c_index(), So if it isn't around, we fake it. In order to map the cdp table entry back to the interfaces() entry, we truncate the last number off of it : # it exists, yay. my $c_index = $device->c_index(); return $c_index if defined $c_index; # if not, let's fake it my $c_ip = $device->c_ip(); my %c_if foreach my $key (keys %$c_ip){ $iid = $key; ## Truncate off .1 from cdp response $iid =~ s/\.\d+$//; $c_if{$key} = $iid; } return \%c_if; =item $cdp->c_index() Returns the mapping to the SNMP2 Interface table for CDP Cache Entries. Most devices don't implement this, so you probably want to use $cdp->c_if() instead. See c_if() entry. (B) =item $cdp->c_ip() Returns remote IP address (B) =item $cdp->c_platform() Returns remote platform id (B) =item $cdp->c_port() Returns remote port ID (B) =item $cdp->c_proto() Returns remote address type received. Usually IP. (B) =item $cdp->c_ver() Returns remote hardware version (B) =item $cdp->c_vlan() Returns the remote interface native VLAN. (B) =back =cut