JezK
Edit File: TrapReceiver.pm
package NetSNMP::TrapReceiver; use 5.00006; use strict; use Carp; require Exporter; require DynaLoader; use AutoLoader; use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $AUTOLOAD); @ISA = qw(Exporter DynaLoader); require NetSNMP::OID; # Items to export into callers namespace by default. Note: do not export # names by default without a very good reason. Use EXPORT_OK instead. # Do not simply export all your public functions/methods/constants. # This allows declaration use NetSNMP::TrapReceiver ':all'; # If you do not need this, moving things directly into @EXPORT or @EXPORT_OK # will save memory. %EXPORT_TAGS = ( 'all' => [ qw( NETSNMPTRAPD_AUTH_HANDLER NETSNMPTRAPD_HANDLER_BREAK NETSNMPTRAPD_HANDLER_FAIL NETSNMPTRAPD_HANDLER_FINISH NETSNMPTRAPD_HANDLER_OK NETSNMPTRAPD_POST_HANDLER NETSNMPTRAPD_PRE_HANDLER netsnmp_add_default_traphandler netsnmp_add_global_traphandler netsnmp_add_traphandler ) ] ); @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } ); @EXPORT = qw( NETSNMPTRAPD_AUTH_HANDLER NETSNMPTRAPD_HANDLER_BREAK NETSNMPTRAPD_HANDLER_FAIL NETSNMPTRAPD_HANDLER_FINISH NETSNMPTRAPD_HANDLER_OK NETSNMPTRAPD_POST_HANDLER NETSNMPTRAPD_PRE_HANDLER ); $VERSION = '5.0903'; # sub new { # my $type = shift; # my ($self); # %$self = @_; # bless($self, $type); # return $self; # } # sub register($$$$) { # my ($self, $oid, $sub) = @_; # my $reg = NetSNMP::TrapReceiver::registration::new($oid, $sub); # if ($reg) { # $reg->register(); # $self->{'regobjs'}{$name} = $reg; # } # return $reg; # } sub AUTOLOAD { # This AUTOLOAD is used to 'autoload' constants from the constant() # XS function. my $constname; ($constname = $AUTOLOAD) =~ s/.*:://; croak "&NetSNMP::TrapReceiver::constant not defined" if $constname eq 'constant'; my ($error, $val) = constant($constname); if ($error) { croak $error; } { no strict 'refs'; # Fixed between 5.005_53 and 5.005_61 #XXX if ($] >= 5.00561) { #XXX *$AUTOLOAD = sub () { $val }; #XXX } #XXX else { *$AUTOLOAD = sub { $val }; #XXX } } goto &$AUTOLOAD; } bootstrap NetSNMP::TrapReceiver $VERSION; # Preloaded methods go here. # Autoload methods go after =cut, and are processed by the autosplit program. 1; __END__ =head1 NAME NetSNMP::TrapReceiver - Embedded perl trap handling for Net-SNMP's snmptrapd =head1 SYNOPSIS Put the following lines in your snmptrapd.conf file: perl NetSNMP::TrapReceiver::register("trapOID", \&myfunc); =head1 ABSTRACT The NetSNMP::TrapReceiver module is used to register perl subroutines into the Net-SNMP snmptrapd process. Net-SNMP MUST have been configured using --enable-embedded-perl. Registration of functions is then done through the snmptrapd.conf configuration file. This module can NOT be used in a normal perl script to receive traps. It is intended solely for embedded use within the snmptrapd demon. =head1 DESCRIPTION Within the snmptrapd.conf file, the keyword "perl" may be used to call any perl expression and using this ability, you can use the NetSNMP::TrapReceiver module to register functions which will be called every time a given notification (a trap or an inform) is received. Registered functions are called with 2 arguments. The first is a reference to a hash containing information about how the trap was received (what version of the SNMP protocol was used, where it came from, what SNMP user name or community name it was sent under, etc). The second argument is a reference to an array containing the variable bindings (OID and value information) that define the noification itself. Each variable is itself a reference to an array containing four values: a NetSNMP::OID object, a string representation of the value that came associated with it, the value's numeric type (see NetSNMP::ASN for further details on SNMP typing information), and the raw value of the trap, encoded according to its type, 64-bit integer types are returned as strings, integer types as integers, strings as strings, object identifiers as NetSNMP::OID objects, and any other types as undefs. Registered functions should return one of the following values: =over 2 =item NETSNMPTRAPD_HANDLER_OK Handling the trap succeeded, but lets the snmptrapd demon check for further appropriate handlers. =item NETSNMPTRAPD_HANDLER_FAIL Handling the trap failed, but lets the snmptrapd demon check for further appropriate handlers. =item NETSNMPTRAPD_HANDLER_BREAK Stops evaluating the list of handlers for this specific trap, but lets the snmptrapd demon apply global handlers. =item NETSNMPTRAPD_HANDLER_FINISH Stops searching for further appropriate handlers. =back If a handler function does not return anything appropriate or even nothing at all, a return value of NETSNMPTRAPD_HANDLER_OK is assumed. Subroutines are registered using the NetSNMP::TrapReceiver::register function, which takes two arguments. The first is a string describing the notification you want to register for (such as "linkUp" or "MyMIB::MyTrap" or ".1.3.6.1.4.1.2021...."). Two special keywords can be used in place of an OID: "default" and "all". The "default" keyword indicates you want your handler to be called in the case where no other handlers are called. The "all" keyword indicates that the handler should ALWAYS be called for every notification. =head1 EXAMPLE As an example, put the following code into a file (say "/usr/local/share/snmp/mytrapd.pl"): #!/usr/bin/perl sub my_receiver { print "********** PERL RECEIVED A NOTIFICATION:\n"; # print the PDU info (a hash reference) print "PDU INFO:\n"; foreach my $k(keys(%{$_[0]})) { if ($k eq "securityEngineID" || $k eq "contextEngineID") { printf " %-30s 0x%s\n", $k, unpack('h*', $_[0]{$k}); } else { printf " %-30s %s\n", $k, $_[0]{$k}; } } # print the variable bindings: print "VARBINDS:\n"; foreach my $x (@{$_[1]}) { printf " %-30s type=%-2d value=%s\n", $x->[0], $x->[2], $x->[1]; } } NetSNMP::TrapReceiver::register("all", \&my_receiver) || warn "failed to register our perl trap handler\n"; print STDERR "Loaded the example perl snmptrapd handler\n"; Then, put the following line in your snmprapd.conf file: perl do "/usr/local/share/snmp/mytrapd.pl"; Start snmptrapd (as root, and the following other opions make it stay in the foreground and log to stderr): snmptrapd -f -Le You should see it start up and display the final message from the end of the above perl script: Loaded the perl snmptrapd handler 2004-02-11 10:08:45 NET-SNMP version 5.2 Started. Then, if you send yourself a fake trap using the following example command: snmptrap -v 2c -c mycommunity localhost 0 linkUp ifIndex.1 i 1 \ ifAdminStatus.1 i up ifOperStatus.1 i up ifDescr s eth0 You should see the following output appear from snmptrapd as your perl code gets executed: ********** PERL RECEIVED A NOTIFICATION: PDU INFO: notificationtype TRAP receivedfrom 127.0.0.1 version 1 errorstatus 0 messageid 0 community mycommunity transactionid 2 errorindex 0 requestid 765160220 VARBINDS: sysUpTimeInstance type=67 value=0:0:00:00.00 snmpTrapOID.0 type=6 value=linkUp ifIndex.1 type=2 value=1 ifAdminStatus.1 type=2 value=1 ifOperStatus.1 type=2 value=1 ifDescr type=4 value="eth0" =head2 Passing Arguments If you need to pass arguments in to the script, you'll need to do it by one of two methods: =head3 Using Subroutines You can either define a subroutine in the file rather than have the file itself do something. IE, in the file if you put: sub foo { print "$_[0]\n"; } and then put these lines in the snmptrapd.conf file: perl do /path/to/script perl foo("hello world"); perl foo("now I am passing something different"); It'd call the foo function twice, and print the results to the console where snmptrapd was started. =head3 Using Variables Or you could always set a variable ahead of time: perl $myVariable = 42; perl do /path/to/script And have the script look for and use the $myVariable value in the script =head1 EXPORT None by default. =head2 Exportable constants NETSNMPTRAPD_AUTH_HANDLER NETSNMPTRAPD_HANDLER_BREAK NETSNMPTRAPD_HANDLER_FAIL NETSNMPTRAPD_HANDLER_FINISH NETSNMPTRAPD_HANDLER_OK NETSNMPTRAPD_POST_HANDLER NETSNMPTRAPD_PRE_HANDLER =head1 SEE ALSO NetSNMP::OID, NetSNMP::ASN snmptrapd.conf(5) for configuring the Net-SNMP trap receiver. snmpd.conf(5) for configuring the Net-SNMP snmp agent for sending traps. http://www.Net-SNMP.org/ =head1 AUTHOR W. Hardaker, E<lt>hardaker@users.sourceforge.netE<gt> =head1 COPYRIGHT AND LICENSE Copyright 2004 by W. Hardaker This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut