Your IP : 3.149.24.70
# -*- mode: perl -*-
# ============================================================================
package Net::SNMP::Transport;
# $Id: Transport.pm,v 3.0 2009/09/09 15:05:33 dtown Rel $
# Base object for the Net::SNMP Transport Domain objects.
# Copyright (c) 2004-2009 David M. Town <dtown@cpan.org>
# All rights reserved.
# This program is free software; you may redistribute it and/or modify it
# under the same terms as the Perl 5 programming language system itself.
# ============================================================================
use strict;
## Version of the Net::SNMP::Transport module
our $VERSION = v3.0.0;
## Handle importing/exporting of symbols
use base qw( Exporter );
our @EXPORT_OK = qw( TRUE FALSE DEBUG_INFO );
our %EXPORT_TAGS = (
domains => [
qw( DOMAIN_UDP DOMAIN_UDPIPV4 DOMAIN_UDPIPV6 DOMAIN_UDPIPV6Z
DOMAIN_TCPIPV4 DOMAIN_TCPIPV6 DOMAIN_TCPIPV6Z )
],
msgsize => [ qw( MSG_SIZE_DEFAULT MSG_SIZE_MINIMUM MSG_SIZE_MAXIMUM ) ],
ports => [ qw( SNMP_PORT SNMP_TRAP_PORT ) ],
retries => [ qw( RETRIES_DEFAULT RETRIES_MINIMUM RETRIES_MAXIMUM ) ],
timeout => [ qw( TIMEOUT_DEFAULT TIMEOUT_MINIMUM TIMEOUT_MAXIMUM ) ],
);
Exporter::export_ok_tags( qw( domains msgsize ports retries timeout ) );
$EXPORT_TAGS{ALL} = [ @EXPORT_OK ];
## Transport Layer Domain definitions
# RFC 3417 Transport Mappings for SNMP
# Presuhn, Case, McCloghrie, Rose, and Waldbusser; December 2002
sub DOMAIN_UDP { '1.3.6.1.6.1.1' } # snmpUDPDomain
# RFC 3419 Textual Conventions for Transport Addresses
# Consultant, Schoenwaelder, and Braunschweig; December 2002
sub DOMAIN_UDPIPV4 { '1.3.6.1.2.1.100.1.1' } # transportDomainUdpIpv4
sub DOMAIN_UDPIPV6 { '1.3.6.1.2.1.100.1.2' } # transportDomainUdpIpv6
sub DOMAIN_UDPIPV6Z { '1.3.6.1.2.1.100.1.4' } # transportDomainUdpIpv6z
sub DOMAIN_TCPIPV4 { '1.3.6.1.2.1.100.1.5' } # transportDomainTcpIpv4
sub DOMAIN_TCPIPV6 { '1.3.6.1.2.1.100.1.6' } # transportDomainTcpIpv6
sub DOMAIN_TCPIPV6Z { '1.3.6.1.2.1.100.1.8' } # transportDomainTcpIpv6z
## SNMP well-known ports
sub SNMP_PORT { 161 }
sub SNMP_TRAP_PORT { 162 }
## RFC 3411 - snmpEngineMaxMessageSize::=INTEGER (484..2147483647)
sub MSG_SIZE_DEFAULT { 484 }
sub MSG_SIZE_MINIMUM { 484 }
sub MSG_SIZE_MAXIMUM { 65535 } # 2147483647 is not reasonable
sub RETRIES_DEFAULT { 1 }
sub RETRIES_MINIMUM { 0 }
sub RETRIES_MAXIMUM { 20 }
sub TIMEOUT_DEFAULT { 5.0 }
sub TIMEOUT_MINIMUM { 1.0 }
sub TIMEOUT_MAXIMUM { 60.0 }
## Truth values
sub TRUE { 0x01 }
sub FALSE { 0x00 }
## Shared socket array indexes
sub _SHARED_SOCKET { 0 } # Shared Socket object
sub _SHARED_REFC { 1 } # Reference count
sub _SHARED_MAXSIZE { 2 } # Shared maxMsgSize
## Package variables
our $DEBUG = FALSE; # Debug flag
our $AUTOLOAD; # Used by the AUTOLOAD method
our $SOCKETS = {}; # List of shared sockets
# [public methods] -----------------------------------------------------------
{
my $domains = {
'udp/?(?:ip)?v?4?', DOMAIN_UDPIPV4,
quotemeta DOMAIN_UDP, DOMAIN_UDPIPV4,
quotemeta DOMAIN_UDPIPV4, DOMAIN_UDPIPV4,
'udp/?(?:ip)?v?6', DOMAIN_UDPIPV6,
quotemeta DOMAIN_UDPIPV6, DOMAIN_UDPIPV6,
quotemeta DOMAIN_UDPIPV6Z, DOMAIN_UDPIPV6,
'tcp/?(?:ip)?v?4?', DOMAIN_TCPIPV4,
quotemeta DOMAIN_TCPIPV4, DOMAIN_TCPIPV4,
'tcp/?(?:ip)?v?6', DOMAIN_TCPIPV6,
quotemeta DOMAIN_TCPIPV6, DOMAIN_TCPIPV6,
quotemeta DOMAIN_TCPIPV6Z, DOMAIN_TCPIPV6,
};
sub new
{
my ($class, %argv) = @_;
my $domain = DOMAIN_UDPIPV4;
my $error = q{};
# See if a Transport Layer Domain argument has been passed.
for (keys %argv) {
if (/^-?domain$/i) {
my $key = $argv{$_};
$domain = undef;
for (keys %{$domains}) {
if ($key =~ /^$_$/i) {
$domain = $domains->{$_};
last;
}
}
if (!defined $domain) {
$error = err_msg(
'The transport domain "%s" is unknown', $argv{$_}
);
return wantarray ? (undef, $error) : undef;
}
$argv{$_} = $domain;
}
}
# Return the appropriate object based on the Transport Domain. To
# avoid consuming unnecessary resources, only load the appropriate
# module when requested. Some modules require non-core modules and
# if these modules are not present, we gracefully return an error.
if ($domain eq DOMAIN_UDPIPV6) {
if (defined ($error = load_module('Net::SNMP::Transport::IPv6::UDP')))
{
$error = 'UDP/IPv6 support is unavailable ' . $error;
return wantarray ? (undef, $error) : undef;
}
return Net::SNMP::Transport::IPv6::UDP->new(%argv);
} elsif ($domain eq DOMAIN_TCPIPV6) {
if (defined ($error = load_module('Net::SNMP::Transport::IPv6::TCP')))
{
$error = 'TCP/IPv6 support is unavailable ' . $error;
return wantarray ? (undef, $error) : undef;
}
return Net::SNMP::Transport::IPv6::TCP->new(%argv);
} elsif ($domain eq DOMAIN_TCPIPV4) {
if (defined ($error = load_module('Net::SNMP::Transport::IPv4::TCP')))
{
$error = 'TCP/IPv4 support is unavailable ' . $error;
return wantarray ? (undef, $error) : undef;
}
return Net::SNMP::Transport::IPv4::TCP->new(%argv);
}
# Load the default Transport Domain module without eval protection.
require Net::SNMP::Transport::IPv4::UDP;
return Net::SNMP::Transport::IPv4::UDP->new(%argv);
}
}
sub max_msg_size
{
my ($this, $size) = @_;
if (@_ < 2) {
return $this->{_max_msg_size};
}
$this->_error_clear();
if ($size !~ m/^\d+$/) {
return $this->_error(
'The maxMsgSize value "%s" is expected in positive numeric format',
$size
);
}
if ($size < MSG_SIZE_MINIMUM || $size > MSG_SIZE_MAXIMUM) {
return $this->_error(
'The maxMsgSize value %s is out of range (%d..%d)',
$size, MSG_SIZE_MINIMUM, MSG_SIZE_MAXIMUM
);
}
# Adjust the share maximum size if necessary.
$this->_shared_max_size($size);
return $this->{_max_msg_size} = $size;
}
sub timeout
{
my ($this, $timeout) = @_;
if (@_ < 2) {
return $this->{_timeout};
}
$this->_error_clear();
if ($timeout !~ m/^\d+(?:\.\d+)?$/) {
return $this->_error(
'The timeout value "%s" is expected in positive numeric format',
$timeout
);
}
if ($timeout < TIMEOUT_MINIMUM || $timeout > TIMEOUT_MAXIMUM) {
return $this->_error(
'The timeout value %s is out of range (%d..%d)',
$timeout, TIMEOUT_MINIMUM, TIMEOUT_MAXIMUM
);
}
return $this->{_timeout} = $timeout;
}
sub retries
{
my ($this, $retries) = @_;
if (@_ < 2) {
return $this->{_retries};
}
$this->_error_clear();
if ($retries !~ m/^\d+$/) {
return $this->_error(
'The retries value "%s" is expected in positive numeric format',
$retries
);
}
if ($retries < RETRIES_MINIMUM || $retries > RETRIES_MAXIMUM) {
return $this->_error(
'The retries value %s is out of range (%d..%d)',
$retries, RETRIES_MINIMUM, RETRIES_MAXIMUM
);
}
return $this->{_retries} = $retries;
}
sub agent_addr
{
return '0.0.0.0';
}
sub connectionless
{
return TRUE;
}
sub debug
{
return (@_ == 2) ? $DEBUG = ($_[1]) ? TRUE : FALSE : $DEBUG;
}
sub domain
{
return '0.0';
}
sub error
{
return $_[0]->{_error} || q{};
}
sub fileno
{
return defined($_[0]->{_socket}) ? $_[0]->{_socket}->fileno() : undef;
}
sub socket
{
return $_[0]->{_socket};
}
sub type
{
return '<unknown>'; # unknown(0)
}
sub sock_name
{
if (defined $_[0]->{_socket}) {
return $_[0]->{_socket}->sockname() || $_[0]->{_sock_name};
} else {
return $_[0]->{_sock_name};
}
}
sub sock_hostname
{
return $_[0]->{_sock_hostname} || $_[0]->sock_address();
}
sub sock_address
{
return $_[0]->_address($_[0]->sock_name());
}
sub sock_addr
{
return $_[0]->_addr($_[0]->sock_name());
}
sub sock_port
{
return $_[0]->_port($_[0]->sock_name());
}
sub sock_taddress
{
return $_[0]->_taddress($_[0]->sock_name());
}
sub sock_taddr
{
return $_[0]->_taddr($_[0]->sock_name());
}
sub sock_tdomain
{
return $_[0]->_tdomain($_[0]->sock_name());
}
sub dest_name
{
return $_[0]->{_dest_name};
}
sub dest_hostname
{
return $_[0]->{_dest_hostname} || $_[0]->dest_address();
}
sub dest_address
{
return $_[0]->_address($_[0]->dest_name());
}
sub dest_addr
{
return $_[0]->_addr($_[0]->dest_name());
}
sub dest_port
{
return $_[0]->_port($_[0]->dest_name());
}
sub dest_taddress
{
return $_[0]->_taddress($_[0]->dest_name());
}
sub dest_taddr
{
return $_[0]->_taddr($_[0]->dest_name());
}
sub dest_tdomain
{
return $_[0]->_tdomain($_[0]->dest_name());
}
sub peer_name
{
if (defined $_[0]->{_socket}) {
return $_[0]->{_socket}->peername() || $_[0]->dest_name();
} else {
return $_[0]->dest_name();
}
}
sub peer_hostname
{
return $_[0]->peer_address();
}
sub peer_address
{
return $_[0]->_address($_[0]->peer_name());
}
sub peer_addr
{
return $_[0]->_addr($_[0]->peer_name());
}
sub peer_port
{
return $_[0]->_port($_[0]->peer_name());
}
sub peer_taddress
{
return $_[0]->_taddress($_[0]->peer_name());
}
sub peer_taddr
{
return $_[0]->_taddr($_[0]->peer_name());
}
sub peer_tdomain
{
return $_[0]->_tdomain($_[0]->peer_name());
}
sub AUTOLOAD
{
my $this = shift;
return if $AUTOLOAD =~ /::DESTROY$/;
$AUTOLOAD =~ s/.*://;
if (ref $this) {
if (defined($this->{_socket}) && ($this->{_socket}->can($AUTOLOAD))) {
return $this->{_socket}->$AUTOLOAD(@_);
} else {
$this->_error_clear();
return $this->_error(
'The method "%s" is not supported by this Transport Domain',
$AUTOLOAD
);
}
} else {
require Carp;
Carp::croak(sprintf 'The function "%s" is not supported', $AUTOLOAD);
}
# Never get here.
return;
}
sub DESTROY
{
my ($this) = @_;
# Connection-oriented transports do not share sockets.
return if !$this->connectionless();
# If the shared socket structure exists, decrement the reference count
# and clear the shared socket structure if it is no longer being used.
if (defined($this->{_sock_name}) && exists $SOCKETS->{$this->{_sock_name}}) {
if (--$SOCKETS->{$this->{_sock_name}}->[_SHARED_REFC] < 1) {
delete $SOCKETS->{$this->{_sock_name}};
}
}
return;
}
## Obsolete methods - previous deprecated
sub OBSOLETE
{
my ($this, $method) = splice @_, 0, 2;
require Carp;
Carp::croak(
sprintf '%s() is obsolete, use %s() instead', (caller 1)[3], $method
);
# Never get here.
return $this->${\$method}(@_);
}
sub name { return $_[0]->OBSOLETE('type'); }
sub srcaddr { return $_[0]->OBSOLETE('sock_addr'); }
sub srcport { return $_[0]->OBSOLETE('sock_port'); }
sub srchost { return $_[0]->OBSOLETE('sock_address'); }
sub srcname { return $_[0]->OBSOLETE('sock_address'); }
sub dstaddr { return $_[0]->OBSOLETE('dest_addr'); }
sub dstport { return $_[0]->OBSOLETE('dest_port'); }
sub dsthost { return $_[0]->OBSOLETE('dest_address'); }
sub dstname { return $_[0]->OBSOLETE('dest_hostname'); }
sub recvaddr { return $_[0]->OBSOLETE('peer_addr'); }
sub recvport { return $_[0]->OBSOLETE('peer_port'); }
sub recvhost { return $_[0]->OBSOLETE('peer_address'); }
# [private methods] ----------------------------------------------------------
sub _new
{
my ($class, %argv) = @_;
my $this = bless {
'_dest_hostname' => 'localhost', # Destination hostname
'_dest_name' => undef, # Destination sockaddr
'_error' => undef, # Error message
'_max_msg_size' => $class->_msg_size_default(), # maxMsgSize
'_retries' => RETRIES_DEFAULT, # Number of retries
'_socket' => undef, # Socket object
'_sock_hostname' => q{}, # Socket hostname
'_sock_name' => undef, # Socket sockaddr
'_timeout' => TIMEOUT_DEFAULT, # Timeout period (secs)
}, $class;
# Default the values for the "name (sockaddr) hashes".
my $sock_nh = { port => 0, addr => $this->_addr_any() };
my $dest_nh = { port => SNMP_PORT, addr => $this->_addr_loopback() };
# Validate the "port" arguments first to allow for a consistency
# check with any values passed with the "address" arguments.
my ($dest_port, $sock_port, $listen) = (undef, undef, 0);
for (keys %argv) {
if (/^-?debug$/i) {
$this->debug(delete $argv{$_});
} elsif (/^-?(?:de?st|peer)?port$/i) {
$this->_service_resolve(delete($argv{$_}), $dest_nh);
$dest_port = $dest_nh->{port};
} elsif (/^-?(?:src|sock|local)port$/i) {
$this->_service_resolve(delete($argv{$_}), $sock_nh);
$sock_port = $sock_nh->{port};
}
if (defined $this->{_error}) {
return wantarray ? (undef, $this->{_error}) : undef;
}
}
# Validate the rest of the arguments.
for (keys %argv) {
if (/^-?domain$/i) {
if ($argv{$_} ne $this->domain()) {
$this->_error(
'The domain value "%s" was expected, but "%s" was found',
$this->domain(), $argv{$_}
);
}
} elsif ((/^-?hostname$/i) || (/^-?(?:de?st|peer)?addr$/i)) {
$this->_hostname_resolve(
$this->{_dest_hostname} = $argv{$_}, $dest_nh
);
if (defined($dest_port) && ($dest_port != $dest_nh->{port})) {
$this->_error(
'Inconsistent %s port information was specified (%d != %d)',
$this->type(), $dest_port, $dest_nh->{port}
);
}
} elsif (/^-?(?:src|sock|local)addr$/i) {
$this->_hostname_resolve(
$this->{_sock_hostname} = $argv{$_}, $sock_nh
);
if (defined($sock_port) && ($sock_port != $sock_nh->{port})) {
$this->_error(
'Inconsistent %s port information was specified (%d != %d)',
$this->type(), $sock_port, $sock_nh->{port}
);
}
} elsif (/^-?listen$/i) {
if (($argv{$_} !~ /^\d+$/) || ($argv{$_} < 1)) {
$this->_error(
'The listen queue size value "%s" was expected in positive ' .
'non-zero numeric format', $argv{$_}
);
} elsif (!$this->connectionless()) {
$listen = $argv{$_};
}
} elsif ((/^-?maxmsgsize$/i) || (/^-?mtu$/i)) {
$this->max_msg_size($argv{$_});
} elsif (/^-?retries$/i) {
$this->retries($argv{$_});
} elsif (/^-?timeout$/i) {
$this->timeout($argv{$_});
} else {
$this->_error('The argument "%s" is unknown', $_);
}
if (defined $this->{_error}) {
return wantarray ? (undef, $this->{_error}) : undef;
}
}
# Pack the socket name (sockaddr) information.
$this->{_sock_name} = $this->_name_pack($sock_nh);
# Pack the destination name (sockaddr) information.
$this->{_dest_name} = $this->_name_pack($dest_nh);
# For all connection-oriented transports and for each unique source
# address for connectionless transports, create a new socket.
if (!$this->connectionless() || !exists $SOCKETS->{$this->{_sock_name}}) {
# Create a new IO::Socket object.
if (!defined ($this->{_socket} = $this->_socket_create())) {
$this->_perror('Failed to open %s socket', $this->type());
return wantarray ? (undef, $this->{_error}) : undef
}
DEBUG_INFO('opened %s socket [%d]', $this->type(), $this->fileno());
# Bind the socket.
if (!defined $this->{_socket}->bind($this->{_sock_name})) {
$this->_perror('Failed to bind %s socket', $this->type());
return wantarray ? (undef, $this->{_error}) : undef
}
# For connection-oriented transports, we either listen or connect.
if (!$this->connectionless()) {
if ($listen) {
if (!defined $this->{_socket}->listen($listen)) {
$this->_perror('Failed to listen on %s socket', $this->type());
return wantarray ? (undef, $this->{_error}) : undef
}
} else {
if (!defined $this->{_socket}->connect($this->{_dest_name})) {
$this->_perror(
q{Failed to connect to remote host '%s'},
$this->dest_hostname()
);
return wantarray ? (undef, $this->{_error}) : undef
}
}
}
# Flag the socket as non-blocking outside of socket creation or
# the object instantiation fails on some systems (e.g. MSWin32).
$this->{_socket}->blocking(FALSE);
# Add the socket to the global socket list with a reference
# count to track when to close the socket and the maxMsgSize
# associated with this new object for connectionless transports.
if ($this->connectionless()) {
$SOCKETS->{$this->{_sock_name}} = [
$this->{_socket}, # Shared Socket object
1, # Reference count
$this->{_max_msg_size}, # Shared maximum message size
];
}
} else {
# Bump up the reference count.
$SOCKETS->{$this->{_sock_name}}->[_SHARED_REFC]++;
# Assign the socket to the object.
$this->{_socket} = $SOCKETS->{$this->{_sock_name}}->[_SHARED_SOCKET];
# Adjust the shared maxMsgSize if necessary.
$this->_shared_max_size($this->{_max_msg_size});
DEBUG_INFO('reused %s socket [%d]', $this->type(), $this->fileno());
}
# Return the object and empty error message (in list context)
return wantarray ? ($this, q{}) : $this;
}
sub _service_resolve
{
my ($this, $serv, $nh) = @_;
$nh->{port} = undef;
if ($serv !~ /^\d+$/) {
my $port = ($serv =~ s/\((\d+)\)$//) ? ($1 > 65535) ? undef : $1 : undef;
$nh->{port} = getservbyname($serv, $this->_protocol_name()) || $port;
if (!defined $nh->{port}) {
return $this->_error(
'Unable to resolve the %s service name "%s"', $this->type(), $_[1]
);
}
} elsif ($serv > 65535) {
return $this->_error(
'The %s port number %s is out of range (0..65535)',
$this->type(), $serv
);
} else {
$nh->{port} = $serv;
}
return $nh->{port};
}
sub _protocol
{
return (getprotobyname $_[0]->_protocol_name())[2];
}
sub _shared_max_size
{
my ($this, $size) = @_;
# Connection-oriented transports do not share sockets.
if (!$this->connectionless()) {
return $this->{_max_msg_size};
}
if (@_ == 2) {
# Handle calls during object creation.
if (!defined $this->{_sock_name}) {
return $this->{_max_msg_size};
}
# Update the shared maxMsgSize if the passed
# value is greater than the current size.
if ($size > $SOCKETS->{$this->{_sock_name}}->[_SHARED_MAXSIZE]) {
$SOCKETS->{$this->{_sock_name}}->[_SHARED_MAXSIZE] = $size;
}
}
return $SOCKETS->{$this->{_sock_name}}->[_SHARED_MAXSIZE];
}
sub _msg_size_default
{
return MSG_SIZE_DEFAULT;
}
sub _error
{
my $this = shift;
if (!defined $this->{_error}) {
$this->{_error} = (@_ > 1) ? sprintf(shift(@_), @_) : $_[0];
if ($this->debug()) {
printf "error: [%d] %s(): %s\n",
(caller 0)[2], (caller 1)[3], $this->{_error};
}
}
return;
}
sub strerror
{
if ($! =~ /^Unknown error/) {
return sprintf '%s', $^E if ($^E);
require Errno;
for (keys (%!)) {
if ($!{$_}) {
return sprintf 'Error %s', $_;
}
}
return sprintf '%s (%d)', $!, $!;
}
return $! ? sprintf('%s', $!) : 'No error';
}
sub _perror
{
my $this = shift;
if (!defined $this->{_error}) {
$this->{_error} = ((@_ > 1) ? sprintf(shift(@_), @_) : $_[0]) || q{};
$this->{_error} .= (($this->{_error}) ? ': ' : q{}) . strerror();
if ($this->debug()) {
printf "error: [%d] %s(): %s\n",
(caller 0)[2], (caller 1)[3], $this->{_error};
}
}
return;
}
sub _error_clear
{
$! = 0;
return $_[0]->{_error} = undef;
}
{
my %modules;
sub load_module
{
my ($module) = @_;
# We attempt to load the required module under the protection of an
# eval statement. If there is a failure, typically it is due to a
# missing module required by the requested module and we attempt to
# simplify the error message by just listing that module. We also
# need to track failures since require() only produces an error on
# the first attempt to load the module.
# NOTE: Contrary to our typical convention, a return value of "undef"
# actually means success and a defined value means error.
return $modules{$module} if exists $modules{$module};
if (!eval "require $module") {
if ($@ =~ /locate (\S+\.pm)/) {
$modules{$module} = err_msg('(Required module %s not found)', $1);
} elsif ($@ =~ /(.*)\n/) {
$modules{$module} = err_msg('(%s)', $1);
} else {
$modules{$module} = err_msg('(%s)', $@);
}
} else {
$modules{$module} = undef;
}
return $modules{$module};
}
}
sub err_msg
{
my $msg = (@_ > 1) ? sprintf(shift(@_), @_) : $_[0];
if ($DEBUG) {
printf "error: [%d] %s(): %s\n", (caller 0)[2], (caller 1)[3], $msg;
}
return $msg;
}
sub DEBUG_INFO
{
return $DEBUG if (!$DEBUG);
return printf
sprintf('debug: [%d] %s(): ', (caller 0)[2], (caller 1)[3]) .
((@_ > 1) ? shift(@_) : '%s') .
"\n",
@_;
}
# ============================================================================
1; # [end Net::SNMP::Transport]